February 5, 2024
Bug Fixes
- Case Information Displays: Fixed a bug with Saving Aux File Options when saving using the aux format. If a filter was used with the object the filter was not used. Now this was fixed.
- Transient Stability: When calling TSSolveAll(YES), a distributed run was not creating multiple-contingency plots. Note, calling TSSolveAll(NO) was working as expected, and this bug only affected distributed runs via the TSSolveAll script command
January 25, 2024
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Many ObjectTypes in AUX files have fields that are a string representing a reference to another object. Those strings have the format of "ObjectType KeyField1 KeyField2 etc". For example, a branch may be represented by the following string: "BRANCH 12345 98765 '12'" . This string is the word BRANCH followed by a SPACE, then integer bus number, followed by a SPACE, and so on. The syntax calls for using a SPACE character as the delimiter between key fields. Users however sometimes edit AUX files in a text editor and may use a TAB character instead of a SPACE. PowerWorld's AUX file parser will now handle a TAB character in those locations and treat them just like a SPACE character.
- Transient Stability: Fixed a bug when closing a generator in transient stability when no governor was available in the generator. This was causing an access violation. This bug was fixed.
January 12, 2024
Features and Improvements
- Transient Stability: Added the ability to open the BusView from the Solution Details tab in Transient Stability. It will open the BusView of the first Mismatch Bus (Mismatch Bus 1).
November 27, 2023
Features and Improvements
- General: Miscellaneous updates
November 7, 2023
Bug Fixes
- Oneline Diagrams: Fixed access violation that could occur when deleting a bus object from a Spatial View when deleting using the Delete key.
October 31, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: Fixed a bug in linear ATC calculations that could result in incorrect OTDF calculations for contingencies that isolate generators or loads.
October 25, 2023
Bug Fixes
- Transient Stability: Fixed a bug with TSSaveTwoBusEquivalent script command. The Bus Number was not processed correctly and also the filename path was not read properly causing an access violation. Both bugs were fixed.
October 20, 2023
Bug Fixes
- Power Flow Solution: Made modifications to how a system state is stored with regard to how angle smoothing occurs after restoring the system state. This avoids some rare situations where angle smoothing occurs in a manner that causes a bad power flow solution.
October 19, 2023
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): The option to "Treat Blanks as Zero" in custom expressions and custom string expressions was not working correctly and could result in an "Unable to evaluate fields" error. This has been fixed.
- Power Flow Solution: When dispatching MW generation when there are multiple generators at the slack bus, changed how the dispatch is done. Generators at limits will respect their limits as long as there are other generators available not at limits. If all generators are over limits, all available generators will be modified. Previously it was possible for generators to move so that they all moved within their available range even if no total change was necessary. It doesn't make sense that generators are adjusting their dispatch unless an actual MW change is required.
- Sensitivity Calculations: When running a shift factor calculation on a full topology model and using the Use Topology Processing Option, it was possible for the system state to remain in the consolidated state if an error occurred while doing the shift factor calculation such as when a calculation is attempted on a branch that is open. This has been fixed.
October 5, 2023
Bug Fixes
- Optimal Power Flow (OPF): When running OPF or SCOPF on a case with multiple generators at the system slack bus, it was possible to get "Unenforceable Generator MW Limits" messages for generators at the slack bus. This would only occur the slack bus itself had multiple generators and some were dispatched at their maximum limit while others were at their minimum limit. This has been fixed.
September 15, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: When using one of the iterated ATC methods and using the option to Report Generation Reserve Limitations, generator reserve limitation limiters should not be iterated on during the step when all limiters are iterated on to determine the individual limiters to iterate on. If generator reserve limits are found during this initial process, the entire process should stop without iterating on individual limiters. Without this change individual limiters would be iterated on.
September 7, 2023
Bug Fixes
- Contingency Analysis: Fixed access violation that could occur during contingency analysis when using Custom Monitors to model cascading outages.
August 28, 2023
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Fixed access violation that would result when loading DynamicFormatting object types from an aux file and fields specified for the Context Object are not supported for that type of object. These fields are just skipped with an error message written to the log.
- File Formats: When an advanced filter condition is using a field instead of a value for comparison, the field will be stored internally using the location number instead of the field name if using the option to show variablenames using names instead of location numbers. This affects fields like custom expressions, custom strings, custom integers, etc. that can be named. Previously, the internal storage could change based on the option setting and could result in the field not being found when loading a PWB with saved filters. This will keep the internal storage consistent regardless of the option.
- User Interface Dialogs: Fixed a bug with the Advanced Filter dialog when a filter includes a Use Another Filter condition, certain circumstances could result in mislinking the target filter.
August 18, 2023
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added the optional parameter PreferenceFilter to the commands InterfaceRemoveDuplicates(PreferenceFilter) and InjectionGroupRemoveDuplicates(PreferenceFilter);
Specify a filter to use when determine which object to keep when there are duplicates. If one object meets the filter and the other object does not, then the object which meets the filter will be maintained and the other removed. Otherwise, the one with a name that would occur first in an alphabetic sort is maintained. - Transient Stability: Bug fix for Transient Stability Contingency Element Dialog. There was an unwanted dependency happening between the Insert, OK and also the Delete button, which caused elements do be added that were not chosen. This has been fixed.
Bug Fixes
August 15, 2023
Bug Fixes
- Transient Stability: Fixed stack overflow error that was introduced in the 8/4/23 when writing REPC_A transient stability models to a DYD file.
August 7, 2023
Bug Fixes
- Power Flow Solution: When a branch had an impedance below the ZBRThreshold and also had a large phase shift or off-nominal tap ratio, it could result in bad power flow convergence. This has been fixed. It was showing up at bus number 516007 in Eastern Interconnection case.
- Transient Stability: Fixed a bug in the parameters Qdn1, Qdn2, Qup1 and Qup2 to ensure they are treated as in per unit on the Plant MVABase for the REPC_C Model
August 4, 2023
Bug Fixes
- Transient Stability: Modified REPC_A, REPCA1, REPC_B, and REPC_C generator models so that the parameters for dbd, fdbd1, fdbd2 always have a fixed sign. Thus if the deadband must always be negative then any edits will automatically take the absolute value and choose the appropriate sign. Also modified so that when writing out to DYD or DYR files these deadbands are written with the sign expected by those formats.
August 2, 2023
Features and Improvements
- Transient Stability: Added ability to read the cmp_mo1ph model as a load component. Model is the same as a MOTORC model.
- Transient Stability: Fixed bug in translating the LDTRPMON records from a DYD File
- Transient Stability: Fixed bug in reading cmpldw2 model from a DYD file
Bug Fixes
August 1, 2023
Bug Fixes
- Transient Stability: Fixed a bug when reading the _CMPLDW model from a dyd file. If the DGDatno was not an integer (for example -100.0 instead of -100) was not reading creating the _CMP_DER_A corresponding model. This bug was fixed and now it will create the DER model if the DGDatno number is not an integer.
July 28, 2023
Bug Fixes
- Transient Stability: Fixed a bug when reading the -cmp_der_a model from a dyd file. If the data ID number was not an integer (for example -100.0 instead of -100) was not reading the model. This bug was fixed and now it reads the model if the data ID number is not an integer.
July 21, 2023
Bug Fixes
- Security Constrained OPF (SCOPF) Tool: When using the DC approximation and running a SCOPF solution, if you have either no contingencies specified, or all active contingencies do not make any changes to the reference state, then the SCOPF would calculate control sensitivities incorrectly and the SCOPF solution did not work. An odd situation, but Simulator will now properly calculate control sensitivities under these conditions.
July 12, 2023
Bug Fixes
- Case Information Displays: PTDF calculations for interfaces did not include the impact of load outages on other branch outages within the interface or the impact of transferring the injection point from a bus to a gen or load in the interface. This has been fixed.
July 7, 2023
Bug Fixes
- Transient Stability: An access violation was caused when using the transient script command TSClearResultsFromRAM(ALL) while one of the contingencies did not have any results. This bug was fixed.
June 28, 2023
Features and Improvements
- File Formats: When reading the hdbexport netmom CSV file, we now read the ND.ELIGIBLE field: if it is FALSE, then we set the respective Simulator's Bus field Monitor = NO.
- File Formats: Added ability to read the TEID field for the records ST, ND, LD, CP, UN, SVS, LN, ZBR, XF, PS, CB, INTRFC, AUX. This field represents the "Transmission Equipment ID". We will read the field and create an object label with the syntax "TEID_12345" where the value 12345 is what is populated in the TEID field in the CSV file.
- Auxiliary Files (SCRIPT and DATA Sections): Device filtering for PartPoint and InterfaceElement object types was not working correctly when used with script commands. This has been fixed.
Bug Fixes
June 14, 2023
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added FaultAutoInsert script command. This script command uses CT_AutoInsert_Options object to set the options.
- File Formats: Fixed a bug that was preventing the creation of transient contingencies whe loading an OTGD file.
Bug Fixes
June 8, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: When running iterated ATC analysis using injection groups as the source and sink and using the option to maintain a constant power factor for loads, the power factor wasn't always being properly cached from the start of the run and could change over the course of the run causing bad solutions if the load crossed 0. This has been fixed.
- Contingency Analysis: Fixed access violation which could occur when using Merit-Order scaling or tripping of an Injection Group in a contingency action or using system scaling if an Injection Group contained another Injection Group.
- File Formats: When loading a RAW file using the special option "Keep all duplicates and update their IDs to make them unique", Simulator was doing this correctly for lines and gens, but was not doing this for transformers. This has been fixed so the special option is used for transformers also.
- General: When using the Scale tool with injection groups and scaling load, the correct power factor wasn't always being used if using the option to maintain a constant power factor for loads. This has been fixed.
May 26, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: Modified the calculation of PTDFs used in ATC calculations to include the impact of losing a participation point due to a contingency outage. If a gen or load in lost due to a contingency, the impact of this injection change will cause a modification to the PTDFs used to calculate the OTDFs.
May 24, 2023
Bug Fixes
- Contingency Analysis: Fixed bug that would not apply the Custom Monitor Pre Filter correctly when the custom monitor specifies a single object to be monitored. The Pre Filter was being ignored.
- Fault Analysis: The Auto Insert Dialog from the Fault Analysis dialog was allowing you to choose either Load or BusGrouping which wouldn't insert anything. These extraneous dialog options have been removed.
- File Formats: Bug fix for writing out to RAW file -- parameters R1-2 and X1-2 and WINDV2 are now written properly according to codes CZ and CW for 2 winding transformers
- Transient Stability: Fixed bug that would delete existing transient stability results in RAM for contingencies set to skip when running with distributed computing.
May 12, 2023
Bug Fixes
- Distributed Computation: Installations now retain distributed computation security settings across patches and major releases.
May 9, 2023
Bug Fixes
- General: Added fix for memory leak in storage of LODF values with doubles
May 8, 2023
Bug Fixes
- Transient Stability: In bug fix from May 5, 2023 for DC Line events, it was now possible for multiple events doing the same thing to show up at the same time in the ResultEvents in transient stability. This has been fixed.
May 5, 2023
Bug Fixes
- Transient Stability: Modified DC Line transient models such as CDC1, CDC4, CDC6, EPCDC so that the timing of blocking could occur immediately upon the application of a fault. The decision to block would be made based on that immediate post-fault voltage. Previously if the voltage recovered back above the Vblock at the end of the time step it would then not block the converter.
May 4, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: When attempting to ramp an ATC transfer with a negative step and the full step amount could not be achieved, the process could stop prematurely without attempting the full step in smaller steps due to a tolerance bug. This has been fixed.
- Contingency Analysis: When auto inserting contingencies by bus grouping, groups with only 1 bus were not being named using the grouping convention to name based on the outside buses of the boundary lines. This has been fixed so these contingencies are named consistently.
- Contingency Analysis: Changed how contingencies are named when automatically inserting contingencies based on bus groupings. It was possible for contingencies to have the same name if basing the name purely on the buses that are on the outside of the grouping. This would cause contingencies to be overwritten and not all expected contingencies were created. Now if a contingency is found with the same name and the contingency actions are different, the lowest bus number internal bus will be appended to the name of the contingency to make the name unique.
- Contingency Analysis: Fixed bug when saving or loading CTG_AutoInsert_Options to or from an aux file when using the BUSGROUPING element type.
April 21, 2023
Features and Improvements
- Transient Stability: Added REEC_E Exciter Transient Model.
- Transient Stability: Improved Algebraic Network Boundary equation solutions at the time of fault or fault clearing for the REGC_B, REGC_C and DER_A machine models.
- Case Information Displays: Fixed bug with the wrong object type being used in the Advanced Filter dialog when the dialog is opened using the Find button on the Filter toolbar.
- File Formats: When loading a DYD file if duplicate _cmp_der_a or _cmp_dgpv with the same data number (such as -103) were read an error occurred. This has been fixed so that whatever the final entry read will be maintained.
- Transient Stability: For both the PlayInGen and InfiniteBusSignalGen machine models, when Rth was not 0 there was a bug. This has been fixed.
Bug Fixes
April 18, 2023
Bug Fixes
- File Formats: Fixed a bug with reading transient stability DC Lines models from a dyd file. The DC Line was read incorrectly because it was expected the DC line id after the second bus and that was causing an error in the format and couldn't add the transient model. That issue was solved and reading the ID in the correct string order was added. Also writing the transient DC line model was corrected to follow the same format.
- File Formats: Fixed error in reading the USRMDL relays models VTGTPA, VTGDCA, FRQTPA, and FRQDCA. Multiple instances at a single generator were not being read properly.
April 17, 2023
Features and Improvements
- Bus View and Substation View Onelines: Forward and backward mouse buttons now work for moving backward and forward in bus views and substation views.
April 13, 2023
Bug Fixes
- File Formats: It was possible to assign an invalid Control Mode to a Switched Shunt that would result in access violations when restoring the system state as part of contingency analysis, and possibly elsewhere. The Control Mode would make it appear that the switched shunt was an SVC, but it was really an invalid type. When loading a PWB file with this incorrect control mode the control mode is now set to Fixed. The error most likely originated from loading a RAW file with a switched shunt control mode of 6 that is not supported in Simulator. When loading RAW files with this control mode the mode is now set to Fixed.
April 11, 2023
Features and Improvements
- Contingency Analysis Tool: Added option to use branch Normal Status when determining Bus Groupings as a standalone or as part of auto inserting contingencies.
- User Interface Dialogs: Fixed showing generator ID on the Breaker Isolated Groups generator table.
Bug Fixes
April 6, 2023
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): In script command "SendToExcel", the "workbookname" and "worksheetname" parameters will let the use of the special keywords @DATETIME, @DATE, @TIME, @BUILDDATE, @VERSION, @CASENAME, @CASEFILENAME, and @CASEFILEPATH.
- Transient Stability: When using Distributed computing in transient stability and you want to change the mode to to "One Contingency at a Time" that will now be allowed to be done without the need for the user to go to the Options and unchecked the "Use Distributed Computing" Option. Once you initially checked the "Use Distributed Computing" checked box a similar option will appear below the Process Multiple contingency options. However, when running One contingency at a time, will not allow the use of distributed computing and as soon as you select the One contingency at a time option it will automatically uncheck the Use Distributed Computing option .
- Transient Stability: Added a new Paux Controller PAUXSS1A.
- Case Information Displays: Fixed secondary filtering of a ContingencyElement, RemedialActionElement, and other similar objects.
- Case Information Displays: TSContingency and TSContingencyElement objects can now be filtered using the following secondary filter object types: Bus, Gen, Load, SwitchedShunt, Branch, Interface, InjectionGroup, DCLine, Area, and LineShunt. TSContingency objects can be filtered using TSContingencyElement filters and TSContingencyElement objects can be filtered using TSContingency filters.
- Contingency Analysis: Fixed access violation that could result if any contingency generator actions for Move, Change By, or Set To are specified for a generator rather than a bus.
- Contingency Analysis: Made significant changes to the Bus Grouping option when auto inserting contingencies. This option uses the Implicit Breakers field specified with buses to create contingencies.
- Difference Case Tool: Difference Case Change Mode Tolerances for Substation Latitude, Longitude, UTM Northing, and UTM Easting were not being applied. This has been fixed.
Bug Fixes
March 24, 2023
Features and Improvements
- Bus View and Substation View Onelines: Modified the Bus View edit box for show the presently selected bus to accept a PASTE action when the paste comes from a spreadsheet.
- Sensitivity Calculations: When clicking on the disabled Linear Calculation Method of "Linearized AC", LODFs were being calculated based on the calculation method that was selected. This would be one of the Lossless DC methods. This could cause confusion with a user thinking that the calculation was being done for the Linearized AC method when it wasn't. The calculation is now only done when the Calculate LODFs button is clicked.
March 23, 2023
Bug Fixes
- Integrated Topology Processing (ITP): Fixed a bug causing a list index out of bounds error when running an SCOPF solution using Integrated Topology Processing when using the DC approximation.
- Security Constrained OPF (SCOPF) Tool: Fixed a bug causing a list index out of bounds error when running an SCOPF solution using Integrated Topology Processing when using the DC approximation.
March 22, 2023
Features and Improvements
- Available Transfer Capability (ATC) Tool: On the ATC dialog the case information displays that list the object changes for multiple scenarios cannot be modified to show different fields. This makes it difficult to save the individual scenario object types with the correct fields directly from their case information displays. The "Save As Auxiliary FIle (x Scenarios)" option found on the local menu for each object type will now save all objects for a scenario type along with the appropriate fields for updating and creating these objects. They are saved in the same manner as they are saved when using the Save Settings button on the ATC dialog to save all ATC settings. A prompt prior to saving the file will allow user input for which key field type to use. If Labels are being used and not all objects have labels, the resulting aux file will be split into objects using labels and objects using primary keys when labels aren't defined.
- Transient Stability: Bug fix. REPC_B model is now written out as PLNTBU1, REAX3U1, and REAX4U1 models in the PSSE DYR file format.
- User Interface Dialogs: When viewing the list of line shunts that belong to a branch when clicking the Line Shunts button on the branch dialog, all shunts belonging to that line should be displayed and no Advanced Filtering or Area/Zone/Owner filtering should be applied. Filtering had been applied and this has been fixed.
Bug Fixes
February 28, 2023
Features and Improvements
- Transient Stability: Modified to prevent WT1T and WT12T1 from accepting improperly defined inputs from a Pref or Plant Controller.
- Power Flow Solution: When changing a switched shunt ControlMode from SVC to any other type, it was possible for an open generator to appear in the case at the location of the switched shunt. This has been fixed.
Bug Fixes
February 24, 2023
Features and Improvements
- Transient Stability: Added the BusView button in the All States string grid in transient stability. Will only open the BusView if the selected object is a Generator, Switched Shunt, Load and a Branch.
- Fault Analysis: When using the "Fault_Options" object with field "DisplayAmps=YES", saving data from the "Fault" objects was not writing out values in Amps, but would always be in per unit.
- Sensitivity Calculations: Fixed an access violation that sometimes occurs when switching to edit mode while the PTDF dialog is open.
Bug Fixes
February 14, 2023
Bug Fixes
- Available Transfer Capability (ATC) Tool: Bug fix for creating contingency interfaces from ATC limiter results. If a circuit ID of a line has only one character, then the name of the interface only contains one character. Previously, it was using the exact 2 character ID as defined in the case, which caused some inconsistencies in strings when customers were trying to compare strings in other software tools.
- Transient Stability: Modified the PlayIn signals so that when they are initialized, if OffSet*Scale > 10 then we automatically calculate an offset to match the initial condition for the respective signal. This was done previously but was done only looking at Offset > 10, so if Scale was a very small number it could cause a problem.
February 13, 2023
Features and Improvements
- Contingency Analysis Tool:
- Transient Stability: Added the ability to enter information in a case information display for zone forward reach and angle with a percentage value for the following distance relay models: ZLIN1, ZQLIN1, OOSLEN, OOSLNQ
- Transient Stability: Modified the REGC_C model to have non-windup limits for +Imax/-Imax on the PI controller for currents
- Contingency Analysis: Various options are available on case information displays showing contingencies to insert, modify, and delete contingencies. Contingency case information displays are available on multiple dialogs like Contingency Analysis, Model Explorer, ATC, etc. Not all of the case information displays would be updated with new information depending on where the action was initiated. This has been fixed.
- Transient Stability: Added an initial limit violation for message for discrete shunts in transient stability
Bug Fixes
February 7, 2023
Features and Improvements
- File Formats: When loading a RAW file with generator records containing a BLANK generator ID, Simulator will now automatically assign a generator ID to these newly created generators. Previously we were creating generators with blank IDs which was incorrect.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed some issues with the "Legacy Complete Model" Aux Export Format Description.
- Oneline Diagrams: When moving a oneline diagram while the Contour ColorKey is visible, the ColorKey as moving twice as much as is should have been. This has been fixed.
- Oneline Diagrams: Fixed bug when selecting Generic Model Field as a context object with dynamic formatting when no other field types are selected. Previously if you wanted to format a bus field that was defined as a Generic Model Field, Bus Field must also be selected as a context object for the format. Now the field will format if only Generic Model Field is selected for the context object.
- Oneline Diagrams: Fixed bug with the PWCaseInformation object type that would not allow a filter to be applied when obtaining a list of these types of objects. There is only one of these object types in the case, so filtering might not make sense, but filtering is required if using this object to display information in a Generic Model Field on a oneline and dynamically formatting this object.
- Transient Stability: For WTGTRQ_A/WTTQA1 models, when limit modification is allowed at initialization, the Qmin/max and Pmin/Pmax values were not being modified. This was causing an initial nonzero derivative.
Bug Fixes
January 26, 2023
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Changes to create contingent interfaces in the script command ATCCreateContingentInterfaces now allows filter to be an optional parameter. Also, the script command now allows the creation of interfaces for base case limiters, which will be created as an interface without a contingency
- File Formats: When writing out transformers to an EPC file, if transformer is Fixed we will now always write type = 1. PowerWorld has a separate field indicating if a transformer's control is enabled and if it's disabled we write a negative sign on the type. However in EPC file type=1 means there is no control at all, so writing a -1 is strange it it means the transformer's control is disabled, but it has no control anyway. To avoid confusion, we just write a 1 instead.
- Transient Stability: Added a new result field for transient stability injection groups. The field is Weighted Average Rotor Speed. The formula is the sum of generator speed times Weight divided by sum of Weights. The intention is to set the Weights to be the H (Inertia) of the generators. The Weights/Inertia are set in the Participation Factors of the injection group.
- Transient Stability: Fixing a bug where the "Do Not Combine RAM Results with Hard Drive Results" setting was interfering with plot generation in Distributed TS runs.
Bug Fixes
January 25, 2023
Bug Fixes
- File Formats: Previously corrections tables for DFACTS devices were not stored in the PWB file format. This has been fixed.
January 23, 2023
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added a new script command with no parameters called CTGDeleteWithIdenticalActions;
This will delete a Contingency object if it contains the identical list of ContingencyElements as another contingency. The contingency with a Name that is first in an alphabetic sort will be maintained. - Auxiliary Files (SCRIPT and DATA Sections): Modified the ExportBusView script command to allow the parameter "Imagetype" to be specified as "PDF".
- Auxiliary Files (SCRIPT and DATA Sections): Added script command CTGSort([SortFieldList]) that will sort the list of contingencies in the data structure that stores the contingencies internally in Simulator. This is different than sorting the contingencies in a case information display. Using this command is useful when using the options to Join Active Contingencies and a sorted ordered is desired when forming new contingencies. The [SortFieldList] parameter is optional and if not specified the list will be sorted in ascending order by contingency name. The SortFieldList parameter is in the format [variablename1:+:0, variablename2:-:1] that is a list of fields by which the list should be sorted, the sort order, and the case sensitivity (ABS for numbers).
- Contingency Analysis Tool: Added a new option on the Other menu in Contingency Analysis dialog under Other\Manage Contingency Definitions\Delete Contingencies with Identical Actions.
This will delete a Contingency object if it contains the identical list of ContingencyElements as another contingency. The contingency with a Name that is first in an alphabetic sort will be maintained. - General: Added an indication on the About box if the license being used is a software or hardware license.
- Auxiliary Files (SCRIPT and DATA Sections): When loading an AUX for TSContingencyElement which was for an InjectionGroup with the action "OPEN ALL" or "CLOSE ALL", an access violation was occurring. This has been fixed.
- User Interface Dialogs: Fixed typos in the display image on the 3-winding transformer dialog showin the tap conversion equations. Equations show "TapNomPri" instead of "TapFixedPri" for example.
Bug Fixes
January 9, 2023
Bug Fixes
- Oneline Diagrams: When MouseWheel scrolling up or down on a oneline to zoom, if the left mouse button was held down while wheeling, the zoom in and out would be performed multiple times. This was incorrect and has has been fixed so that the left mouse button does not effect this behavior.
- Oneline Diagrams: When using ALT+TAB to switch between programs and move away from PowerWorld Simulator, the "snap to grid" feature of PowerWorld's oneline diagrams would stop working. It would work again after the user pressed the ALT key down and released, but until then the snap to grid would not work. PowerWorld was registering the ALT key going down to temporarily disable the snap to grid, but because the ATL+TAB switched programs the ALT key coming back up was not being registered by PowerWorld. This has been fixed so that when returning back to PowerWorld the snap to grid would resume working.
January 5, 2023
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Fixed error with new filename checking that was added to the ExportBusView script command.
January 4, 2023
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with ExportBusView script command that would not allow specification of the filename with all of the special features such as the @ keywords or a prompt for a save dialog.
- Fault Analysis: Substantially increased the calculation speed when running a large number of steady state fault analysis calculations for bus faults.
- General: Change to allow Transformer Impedance Correction Tables to have values greater than 127.
- Oneline Diagrams: Fixed error were loading in DisplayBus objects from an AXD file which caused it to potentially not update fields
- Transient Stability: Modified the CDC1, CDC4T, CDC6, and CDC6T DC line models so that the Voltage-Dependent Current Order Limit (VDCOL) always uses the inverter DC voltage in kV.
December 23, 2022
Bug Fixes
- Contingency Analysis: Added local menu options on Custom Monitor case information display found on the Contingency Analysis dialog to Save As > Auxiliary File (all related info) and Save As > Auxiliary File (all related/only selected records). These options will save the custom monitors along with any Advanced Filters and other dependent objects needed to define the monitors.
December 19, 2022
Features and Improvements
- Transient Stability: Modified TSValidation object so they can show the DataMaintainer of the underlying model object.
- Transient Stability: Renamed the parameter on REGC_C which freezes the PLL state to Vpllfrz.
- Transient Stability: REEC_D has input parameter MVABase which specifies the model MVAbase. This impacts the inputs of Pe and Qgen in the model. Typically MVABase=0 which means that the machine MVAbase is used instead. This patch fixes an error when the using line-drop compensation in the REEC_D model to ensure this model MVABase is used if specified.
- Transient Stability: Fixed error in HYG3 governor model when Cflag>0 and Td=0 with the handling of the ignored state due to Td=0.
Bug Fixes
December 12, 2022
Bug Fixes
- File Formats: Customers have reported that renewable dynamic machine models do not function when read from DYR models in other software if the power flow generator model flag WMOD do not set to a 1. When writing out a RAW file, if the WindControlMode in PowerWorld is set to none, then the generator WMOD field in the RAW file will be determined by the type of dynamic machine model used for the generator. For machine models that are for renewable machines (WT1G, WT2G, WT3G, WT4G, REGC*, PVD1, PV1G, and so on), the WMOD will be written as a 1 and for other generators the value will be a 0.
- Transient Stability: Customers have reported that renewable dynamic machine models do not function when read from DYR models in other software if the power flow generator model flag WMOD do not set to a 1. When writing out a RAW file, if the WindControlMode in PowerWorld is set to none, then the generator WMOD field in the RAW file will be determined by the type of dynamic machine model used for the generator. For machine models that are for renewable machines (WT1G, WT2G, WT3G, WT4G, REGC*, PVD1, PV1G, and so on), the WMOD will be written as a 1 and for other generators the value will be a 0.
December 7, 2022
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with InsertConnectedBuses script command that will not find a data bus if the input is enclosed in quotes.
- File Formats: Added ability to read ND outages from the CTGL records of the Areva HDBEXPORT CSV files for contingency definitions.
- General: Fixed bug that would cause "Cannot subscribe to reference notification publisher during destruction" errors.
- Transient Stability: There is an issue with the way we report the BusNum in Transient stability and the associated Bus Object. The reason for this is when the power flow is set to use the Consolidated Topology Case the Bus object for the Transient Stability is different from the full topology and was affecting the behavior of the script command "TSDisableMachineModelNonZeroDerivative". Now the script command is disabling the machine models in the correct generator with non-zero derivatives.
- Transient Stability: For TSDisableMachineModelNonZeroDerivative script command treat empty parentheses as having no parameters defined and use the defaults. This had been assuming there was a single blank parameter defined that could not be converted to a floating point value and was producing an error.
- Transient Stability: When showing transient objects in the All States and State Limit Violations case information displays and using topology processing, the objects were being shown by the consolidated identifying information. This has been fixed to show the full topology identifying information.
- Transient Stability: Fixed bug on OEL1 exciter in which its violation time was not being property reset so it would instantaneously trip if the current went above the threshold for a second time.
- User Interface Dialogs: Fixed bug with the Gen Curves that could cause them to not function.
December 1, 2022
Features and Improvements
- Transient Stability: Added ability to use Custom Expressions and Custom String Expressions with transient stability model object types.
November 17, 2022
Bug Fixes
- Case Information Displays: Fixed a bug with Switched Shunt type svsmo1 and svsmo3. When the shunt was at a limit it was showing the wrong mismatch in the model explorer. The solution of the power flow was correct just the mismatch table was showing the wrong mismatch for the bus.
- Transient Stability: Fixed bug when using an SVSMO3 stability model if the power flow case was not also configured to use the SVC Type of svsmo3.
November 16, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added new script command: ExportBusView(filename, BusID, FileType, width, height, QualityOptions). Quality Options are optional.
Examples:
ExportBusView("c:\temp\bus1a.jpg", [Bus 1], JPG, 640, 480);
ExportBusView("c:\temp\bus1b.jpg", [Bus 1], JPG, 640, 480, [100, 1]);
ExportBusView("c:\temp\bus2.gif", [Bus 2], GIF, 800, 600, [1, 0.1, 1]); - Oneline Diagrams: Bug fix so images copied to the clipboard can consistently be pasted into other programs (such as Paint).
- Transient Stability: The new script command TSTransferStateToPowerFlow was not working correctly and has been fixed.
Bug Fixes
November 10, 2022
Features and Improvements
- Transient Stability: State 7 PIIntegrator of UEL2C now reports PI output value, instead of the internal state
November 8, 2022
Features and Improvements
- File Formats: Added a warning message when reading a RAW file if substation switching devices are found to be between different buses.
- PV and QV Curve (PVQV) Tool: Added new field with PWPVResultListContainer objects called RemedialActionApplied. This field will indicate if at least one remedial action element was applied for the contingency.
- Transient Stability: Added script command TSTransferStateToPowerFlow(CalculateMis) for allow transferring TS state to the power flow as the dialog allows for. (CalculateMis is either YES or NO and indicates whether
- Transient Stability: When a transient simulation initializes such that the UEL2 model is active at the initial condition, then this represents an initial limit violation. In this situation, if the user option "Modify Limit and Run" has been chosen, then PowerWorld will NOT send a signal to exciter from this UEL2 for the entire simulation. This will allow the exciter to initialize in steady state. The logic here is that entire UEL2 model represents a limit, so if it is active then it is an initial limit violation.
- Transient Stability: Allow the generic object types that show the listing of all transient stability models of a particular type to be accessed through auxiliary and script commands for listing, filtering, and deleting objects. Objects cannot be modified through these generic object types.
- User Interface Dialogs: added the PowerFactor value to the Load Run Mode dialog
- User Interface Dialogs: Modified the dialog show devices that regulate a particular bus to show whether a switched shunt is using the RegTargetVoltHigh value. Also greyed out the value if it is not being used.
- Fault Analysis: Fixed bug of missing neutral impedance values when writing zero sequence data for three winding transformers to SEQ file.
- Sensitivity Calculations: When running a large number of elements for Multiple Element Shift Factor analysis, opening the Display/Column Options dialog for the results grids could be very slow. This has been fixed. Along with this change opening Display/Column Options on other case information displays that allow the display of a large number of sensitivity calculations has been sped up.
- Sensitivity Calculations: When running Multiple Element Shift Factor analysis for lines through the GUI and errors are encountered, there is now an option to skip all remaining error messages or abort the entire process.
- Transient Stability: When the software is allowed to modify limits during initialization, the Imax parameter in REEC_A, REEC_B, REEC_C and REEC_D models is modified to allow for the initial current commands.
- Transient Stability: When the software is allowed to modify limits during initialization, the VDLP and VDLQ lookup tables in REEC_A, REEC_C and REEC_D models are not used if their values are inconsistent with the initial current commands
- Transient Stability: When the software is allowed to modify limits during initialization, the Ke parameter in REEC_D is modified to allow the initial real current command.
- Transient Stability: When the software is allowed to modify limits during initialization, when REEC_A and REEC_B models are associated with a generator with an initial negative MW output, this is treated as a validation error. Autocorrection will make such a model Not Active.
- Transient Stability: When storing VSC DC Line transient results to hard drive this could cause errors in the hard drive storage for some devices other than Bus, Gen, Load, AC line, Transformer and DC lines. Most customers do not have VSC DC Lines defined in their case and were not storing these results so this was not noticed previously.
- Transient Stability: For the UCBGT and UCCPSS governor models, fixed the treatment of non-windup limits for the 3 states feeding into the Low Value Select block when the proportional gain is zero so that the integrator state would not windup. When Kp<>0 this was already handled.
- Transient Stability: For the GGOV1 governor, when Kpgov=0, changed the Kigov integrator state to be a non-windup limit with limits Vmax/Vmin. When Kpgov<>0 this was already acting as a non-windup limit and the vast majority of GGOV1 implementations have Kpgov<>0.
Bug Fixes
October 27, 2022
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added new field with TransferLimiter objects called RemedialActionApplied. This field will indicate if at least one remedial action element was applied for the contingency. This field is only valid for IterativelyFound results of YES, NO, or blank.
- File Formats: Added log warning messages for invalid Terminal Equipment Data when reading substation topology
- File Formats: Added 'Load Contingencies Complete' and 'Load RAS Complete' messages at the end of the hdbexport contingency and RAS import routines.
- QV Curves: Added new field with QVCurve objects called RemedialActionApplied. This field will indicate if at least one remedial action element was applied for the contingency.
- Transient Stability: Modified PSS2C, PSS3C, PSS6C, and PSS7C stabilizers to include Tpgfilt parameter as a time constant for measuring Pgen for use in the PSS Output logic decisions. Added reading and writing this parameter from the DYD format.
- Transient Stability: Modified PSS2C, PSS6C, and PSS7C stabilizers to include Xcomp and Tcomp parameter for use in the compensated frequency calculation. Added reading and writing these parameters from the DYR file.
- Auxiliary Files (SCRIPT and DATA Sections): Under certain conditions loading an AUX file could result in a star bus being shared between 3 winding transformers. This should never be allowed. The code has been updated to detect this and create a new star bus when this situation is encountered.
- Power Flow Solution: Note that unless a user entered something into PowerWorld's special "Slack Bus Priority" field the following change makes no difference. When using a slack bus priority to determine the slack for an island, we were not checking the conditions that determine if an island is viable like having load, being connected to a dc line, or having more than one bus. This could result in islands that have only a single generator and nothing else in them, which doesn't make much sense. Now these checks are done. If a bus should be a slack regardless of the rest of the island viability checks the Slack field for the bus should be set to YES.
- Transient Stability: Default value of Trate for the H6E governor was 163. The default is now 0.0 and means to use the generator MVABase which is what all other governors default to.
- Transient Stability: Features were added in the May 26, 2022 patch modifying how the automatically determined Min and Max vertical axis scales were determined. These worked correctly when the plot was first opened, but were not properly recalculating the min/max scale while an already opened plot was updated. For example, using the legend to hide/show plot series would not automatically updated the scale. Nor would a plot updating with additional new time-series be updated correctly. This has been fixed.
- Transient Stability: Modified script command TSDisableMachineModelNonZeroDerivative(MaxAbsDerivative) to use a default value of 0.001 if not specified instead of a value of 0.
Bug Fixes
October 13, 2022
Features and Improvements
- Contingency Analysis Tool: Added new field with Contingency object type called RemedialActionApplied that indicates if at least one remedial action element was implemented for the contingency. Valid entries are Yes, No, and Blank. If left blank then no information is known about whether or not a remedial action element was implemented.
- Contingency Analysis Tool: Added new field with ContingencyPrimary and CTGComboResults objects called RemedialActionApplied. This field will indicate if at least one remedial action element was applied for a Primary contingency for the ContingencyPrimary object. With the CTGComboResults object this field indicates if at least one remedial action element was applied after the secondary contingency was applied when reported with the CTGComboResults object.
- Transient Stability: Added a new TS script command: TSDisableMachineModelNonZeroDerivative(MaxAbsDerivative);
This script command will look for the derivatives of all the transient stability models states associated with a particular generator. If any absolute value of a state in any of the models of that particular generator is greater than the MaxAbsDerivative, it will Deactivate the Active Machine Model for that generator. - File Formats: When reading the DYD format, now look for special syntax in the plant controller repc_b for the mvabase of the repc_b model using the syntax normally reserved for machine models of mva=123 immediately after the : in the model invocation. Also will write this out to the DYD for repc_b models.
- Transient Stability: Fixed a bug with transient stability limit monitors. When using the cumulative time setting with multiple contingencies there was a bug when using the Re-evaluate to Get Limit Monitor Violations button. It was not re-setting the cumulative timer of the limit monitor when changing from one contingency to another and was creating incorrect limit violations. This issue is now fixed.
Bug Fixes
October 7, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added new script command CTGPrimaryAutoInsert that takes no parameters. It will auto insert Primary Contingencies using the options specified with the CTG_AutoInsert_Options object.
- Transient Stability: The option to "Save Transient Stability Data -> Only Records Modified in Difference Case" will now use the Area/Zone filters.
- Transient Stability: Bug fix for the validation of excitation limiter model OEL1 models. When runback=0, then it is an allowed configuration with any exciter.
Bug Fixes
October 4, 2022
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that would open a save dialog when saving the entire case as an auxiliary file using the SaveCase script command.
September 30, 2022
Features and Improvements
- File Formats: Completed the ability to load RAW Version 35 files which have full-topology modeling of substations included. Also working on the ability to write those files back out a RAW 35 format.
- General: Do not allow Simulator to be closed by clicking the X on the main dialog while a case is being opened.
Bug Fixes
September 28, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added new options to the right-click menu of a the Message Log to
For AUX load, add Log Message for Existing Objects Edited
For AUX load, add Log Message for New Objects Created
These 2 options are NOT checked each time PowerWorld is opened, but can be checked to generate log messages for every edited object or for every created object as AUX files are loaded. Normally this is not wanted but can be useful to ensure you are not editing existing objects when you were not expecting to. - Case Information Displays: Modified Bus fields for showing GenRemRegMvar, GenRemRegMvarMin and GenRemRegMvarMax so that they return blanks if there is no remote regulation (previously they showed a value of 0.0). This is consistent with other fields GenRemRegAVR, GenRemRegVoltError, and GenRemRegVoltSet
- Transient Stability: Added a new option in Transient Stability Limit Monitors to use Cumulative Time to determine when a violation occurs. The Option when set to YES will use the cumulative time a violation occurs during a simulation to determine if the time duration of a violation is exceeded. Without the option the time use to determine the duration time is reset when a violation is no longer occurring and was less than the duration time. With this option set to YES the duration time will not be reset during the entire simulation.
- Available Transfer Capability (ATC) Tool: When running Multiple ATC Scenarios, we now will clear out any existing results in the event that implementing the scenario doesn't work.
- Available Transfer Capability (ATC) Tool: When running distributed computing for ATC and a scenario does not complete without errors, an error is not longer raised to indicate that the distributed process had a failure. When this happened the scenario might be attempted again depending on the number of errors allows with each distributed computer, but there is no point in that because the failure is most likely due to a problem with the scenario and the power flow solving. The error that is returned from the scenario attempt is added to the log for the scenario.
- Case Information Displays: When loading in an AUX file, the "Limit Group" for Buses, Branches, Interfaces and BusPairs is now read in before other dependent fields are read in. For Buses, "Use Specific Limits" is read in prior to reading in the the "Limit Group"
- File Formats: When using the SaveCase script command it was possible that an island slack bus set by the user might not be treated as such when saving the case as a PWB. When opening the PWB there would be no island slack specified so Simulator would automatically pick a bus. This has been fixed so that the island slack bus specified by the user is retained when saving a PWB.
- Optimal Power Flow (OPF): In extremely over-constrained OPF or SCOPF solutions (often with many 100s of unenforceable constraints), it is possible for the cost of enforcing generator MW limits to get so high that the linear program chooses to dispatch generators outside limits. These cases are rare, but we have modified so that generators will still not be dispatched more than 10% outside limits in this situation to make it easier for the user to debug the situation.
Bug Fixes
September 21, 2022
Features and Improvements
- File Formats: Modified reading of CP records from hdbexport CSV files when VTARGET is not defined.
We now set the RegHigh/RegLow = 1.4/0.6 for shunts and also set AutoControl = NO. - File Formats: Modified reading of XF records from hdbexport CSV files when VTARGET is not defined.
We now set the RegMax/RegMin = 1.4/0.6 for transformers and also set AutoControl = NO. - Case Information Displays: Fixed access violation that could result when trying to send data to Excel using the Transpose option if the number of original columns exceeded the allowed number of columns in Excel (which limits columns to 16384)
- GIC: Fixed bugs with how GIC was using handling DC Lines, VSCDCLines and MultiTerminalDC objects when terminals were not assigned to a substation.
- Optimal Power Flow (OPF): When a Super Area is on OPF control and the power flow is being solved, the OPF option of how to treat this control method was not applied correctly if the option was set to No Area Control. The areas in the super area were following their own AGC methods, but no area or super area control should be done. This has been fixed.
- Optimal Power Flow (OPF): Fixed a bug that would cause areas to be removed from their super areas if the areas were solved on Economic Dispatch control while AGC control for the super area was set to Off AGC.
Bug Fixes
September 15, 2022
Bug Fixes
- Transient Stability: Fixed bug in SCOPF when working with full topology (consolidated) cases. The contingency analysis generates violations in terms of unconsolidated system elements. We were using these incorrectly in the consolidated model to calculate sensitives, which was causing a difference in solution between the consolidated and unconsolidated models. This has been fixed.
September 14, 2022
Features and Improvements
- Security Constrained OPF (SCOPF) Tool: Fixed bug in SCOPF when working with full topology (consolidated) cases. The contingency analysis generates violations in terms of unconsolidated system elements. We were using these incorrectly in the consolidated model to calculate sensitives, which was causing a difference in solution between the consolidated and unconsolidated models. This has been fixed.
September 12, 2022
Features and Improvements
- Transient Stability: Added support to read and write from a PSLF dyd file for Transient Stability models
ESAC10C (AC10C in PowerWorld)
ESST2C (ST2C in PowerWorld)
ESST3C (ST3C in PowerWorld)
ESST7C (ST7C in PowerWorld)
ESST8C (ST8C in PowerWorld)
ESST9C (ST9C in PowerWorld) - Transient Stability: Added support to read and write from a PSSE dyr file for Transient Stability models
ST7C (ST7C in PowerWorld) - Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with saving Model Conditions to auxiliary files from a case information display. By default they should be saved using separate data sections for ModelConditions and ModelConditionConditions but they were being saved using SubData. When using the Save to Auxiliary with Options and choosing to save with SubData would not save anyting in the SubData section. This has all been fixed.
- General: Fixed bug merging buses across the terminals of selected lines. An error could be encountered if one of the terminals was connected to a dc line, but this should be fixed.
- Oneline Diagrams: Fixed bug when drawing phase shifter symbols if the terminal buses are directly on top of each other. There could be a line drawn from the phase shifter symbol to infinity at the top left of the oneline. This will no longer appear.
- Sensitivity Calculations: Modified the bus fields shown by default of the Self-Sensitivity tab of the Sensitivities\Flows and Voltage dialog.
Negative Reactance Lines: this will now return NO if a neighbor branch has a negative X but this branch connects to the internal star bus of the equivalent of a three-winding transformer. The Star bus itself will still say YES, but the terminals of the three-winding transformer will return NO.
Likely Alternative Solution Fields: These fields will now return YES if a terminal of a three-winding transformer has a negative dV/dQ even if the connection to the star bus has a negative X. - Sensitivity Calculations: When attempting to calculating shift factors on a branch that was not online, an error message would be presented saying that the transactor and study device "do not share any common viable electric island". While this is true (since the open branch is not in ANY island), it was confusing. The error will now simply say that the "study device is not online" instead.
- Transient Stability: Transient Stability stores various statistical information about all generators in the case (This is called Minimum/Maximum Values in the Results from RAM). There were entries in this table for internal fictitious generators with an ID of "<0". These were not harming or breaking anything in the software, however showing these results as generators is confusing. This has been removed to avoid confusion.
- Transient Stability: Modified the initialization of the H6E governor models to ensure they initialize to a flat start. Limitation in the gate position prevent the Pmech from being achieved are now handled by modifying the Hdam value instead for H6E. In addition, the initialization for the gate position was improved.
- Transient Stability: For truly bad input data on synchronous machine models, checks on (Xqpp > Xqp) could conflict with checks on the ratio of (Xqpp/Xdpp). Modified the auto-correction routines in these situations to just leave the Xqpp value alone and return an error to force the user to go correct these models.
Bug Fixes
September 1, 2022
Features and Improvements
- Contingency Analysis Tool: Added a "Selected" filtering option to the result objects in the Contingency Combination Analysis dialog. Also modified the layout of those options on the dialog.
- File Formats: When reading a RAW file set the 'Default' Limit Set for contingency voltage rating set to B to match how bus specific limits are loaded; the Normal bus ratings are put in rating set A and the Contingency bus ratings are put in rating set B.
- Transient Stability: Added support to read and write from a PSLF dyd file for Transient Stability models
ESAC3C (AC3C in PowerWorld)
ESAC4C (AC4C in PowerWorld)
ESAC5C (AC5C in PowerWorld)
ESAC6C (AC6C in PowerWorld)
ESDC1C (DC1C in PowerWorld)
ESAC7C (AC7C in PowerWorld)
ESAC9C (AC9C in PowerWorld) - Auxiliary Files (SCRIPT and DATA Sections): When using the special All value in a list of fields in a script command or via SimAuto, modified so that "All" would be treated the same as All.
Also for stability models when using the special AllModelParams, AllModelParamsPriKey, AllModelParamsSecKey,a nd AllModelParamsLabel, modified to handle removing double quotes from around these. - Available Transfer Capability (ATC) Tool: When using the option with linear contingency analysis to "Iterate on Action Status" it was possible for the branch fields that return the percent loading of the line based on limit monitoring settings (% at From, % at To, and % Used) to be calculated based on MVA when amps should be used or amps when MVA should be used when these fields were used as part of Model Conditions used with RAS.
- File Formats: When writing out Zone data to RAW files, PowerWorld was truncating the zone names to 8 characters. PowerWorld will now truncate to 12 characters instead to match the limitation in the RAW file format.
Bug Fixes
August 29, 2022
Features and Improvements
- Transient Stability: Added support to read and write from a PSLF dyd and PSSE dyr file for Transient Stability models OEL2C and UEL2C.
- Transient Stability: Added support to read and write from a PSLF dyd file for Transient Stability models ESAC1C (AC1C in PW) and ESAC2C (AC2C in PW).
- File Formats: Modified loading of Areva hdbexport files in several cosmetic ways as follows
1. For LN2, XF2, ZBR2 records we were loading in RMEAS and WMEAS values into CustomFloat entries of the resulting Branch record in PowerWorld Simulator. This has been modified so that if entries are not found (values are blank) then we leave the custom float values as blank to indiciate they were unspecified. Previously they would come in as 0.000 instead. Also modified the order to that CustomFloat:0 = WMEAS; CustomFloat:1 = ZWMEAS; CustomFloat:2 = RMEAS; CustomFloat:3 = ZRMEAS.
2. Added the ability to include a KVMEAS value with each BS record in the CSV file. This value is then populated on every bus (ND record) created for this BS record as CustomFloat:0. If KVMEAS is blank then the CustomFloat:0 value remains blank.
3. When loading UN and LD objects the WMEAS and RMEAS are populated as CustomFloat:0 and CustomFloat:1. Previously if WMEAS and RMEAS were empty, then a value of 0.000 was assigned. This has been changed so that the values remain blank if they are not specified.
4. When loading LD objects the values for I_LDAREA, PARFRACW, and PF are used to create InjectionGroup objects in PowerWorld appropriate for performing load scaling in your case in a manner consistent with what is done in the EMS. This remains, however we have now also added extra custom values to the Load objects in PowerWorld to give you another way to see this information. CustomFloat:2=PARFRACW; CustomFloat:3=PF; CustomString:0=I_LDAREA.ID; CustomString:1=LDTY.
5. Reading of MONGRP objects in the CSV file resulted in the creation of PowerWorld LimitSet objects. Previously we had the prefix M_ on all LimitSet names. This prefix has been removed.
6. When reading ND records if the associated MNL record (from either ND, KV or CO record) has I_VLIM=0, then PowerWorld was always assigning the Bus to the Default LimitSet so that it would not be monitored. This was functionally fine because it meant that the voltage limits were not used (they were being set to Vlow=0.0000 and Vhigh=2.0000), however the user lost the assignment of the bus to a LimitSet. We now assign the LimitSet based on the MNL records I_MONGRP, however the Bus will be set to Monitor=NO.
7. When loading in LNLIM, XFLIM, and ZBLIM records, if the I__MNL=0 we now set PowerWorld's branch field Monitor=NO. Previously, these branches were assigned to the default limit group which was not monitored so the software function is not changed, but setting Monitor=NO made it more clear that no monitoring of that branch is done.
8. When loading an INTRFC record, if I__MNL=0 we now set PowerWorld's Interface field Monitor=NO. Previously, these branches were assigned to the default limit group which was not monitored so the software function is not changed, but setting Monitor=NO made it more clear that no monitoring of that branch is done.
9. When loading CP records, if the REG__ND=0 the shunt is now always set to ShuntMode=Fixed. Previously the AutoControl was being set to NO, but the ShuntMode may remain as Discrete. This doesn't change software function but makes it more clear what was intended in the hdbexport format.
10. When loading XF records from and hdbexport file the RegTargetType for branches is now always set to "Max/Min".
11. When loading in XF records, if the REG__ND=0 the branch ControlType is always set to Fixed now. The VTARGET associated with these records were always blank, so we were setting AutoControl=NO regardless, but this makes it more clear the transformer has no control. - General: When tapping a transmission line, the owner of the new bus is now set to the owner of the near bus of the line being tapped. The owners of the new lines are set to the owners of the line being tapped. Previously the owners were not being set for the new bus and new lines, which could result in access violations.
- Power Flow Solution: PowerWorld keeps track of when the creation (and removal) of electrical islands are needed as branches are opened and closed. We will dynamically add or remove island slack buses to accommodate the new islands. When doing this dynamically, for an island to be considered viable, we require it to have at least some online generation and some online load. As a result some checks are needed when opening and closing generators or loads as well. Those were being done appropriately to make an island dead if all generation or load was opened, however there were some situations when closing in a generator or load to a presently dead island for which PowerWorld did not automatically choose a new slack bus and energize the island. This has been fixed so that in these situations a new energized island created.
- Transient Stability: The Q/P ratio reference input for REEC_A/B/C/D models can now be changed by using the setting the exciter setpoint during a dynamic simulation.
Bug Fixes
August 24, 2022
Features and Improvements
- Case Information Displays: Added fields for a generator to show the minimum and maximum points for MW and Mvar for a reactive capability curve.
- Data Checks: DataChecks could be defined for any transient stability model object and viewed in the special DataCheck summary dialog inside PowerWorld Simulator, however the fields for viewing results of data check for a stability model were not available for use in other displays or via scripting. This has been fixed.
- File Formats: When reading and writing transformer records in the EPC file will now recognize a negative "type" as an indication that control on this device is disabled.
- Transient Stability: Modified the new REGC_C model so that the network equations use the PLL angle for the network to model reference transformation. Previously the PLL angle was used for doing the transformation for modeling the current controls, but not the network equations.
- Available Transfer Capability (ATC) Tool: Fixed bug that might not allow pasting changes from Excel into ATC line rating change scenarios because the key fields could not be identified when using column headers to identify fields.
- Available Transfer Capability (ATC) Tool: Fixed bug that would remove the Label field in Line and Generator ATC Scenario case information displays when pasting in new data.
- Data Checks: DataChecks could be defined for any transient stability model object and viewed in the special DataCheck summary dialog inside PowerWorld Simulator, however the fields for viewing results of data check for a stability model were not available for use in other displays or via scripting. This has been fixed.
- GIC: For GIC corrected the electric field V/mile and V/km values being flipped.
Bug Fixes
August 22, 2022
Features and Improvements
- Transient Stability: Added ability to read from DYR files the REPCC, REECD1, and WTGWGOA models
- Transient Stability: Added ability to read from DYD files the REPC_C, REEC_D, and WTGWGO_A models
- Transient Stability: Added support to read and write from a PSLF dyd and PSSE dyr file for Transient Stability Stabilizer models PSS6C and PSS7C.
- File Formats: Modified to write out EPC files with up to 32 characters for the substation names. An older version of PSLF only supported 12 characters
- GIC: Bug fix for setting up GIC time-varying series voltage input on reopening a PWB file with B3D file(s) referenced
Bug Fixes
August 19, 2022
Bug Fixes
- Case Information Displays: Fixed access violation that would occur if the interface case information display is open and interfaces are deleted by loading an auxiliary file.
- Transient Stability: Fixed a bug with the option "Show in Case Information Display" located in Transient Stability Plots tool. The table was showing empty if the data associated with the plot series was only saved in Hard Drive. Now it will ask the user if want to load the data from the Hard Drive. If Yes then the table will be created with the Hard Drive data.
- Transient Stability: When pressing "Load from Hard Drive File into RAM results specified by Store to RAM Options" in the Results from RAM in Transient Stability it will also look at the plots and if any is defined it will also load the data associated with the plot series from the plots.
- Transient Stability: Bug fix for an "invalid floating point operation" error which happened during the modification of limits at initialization for hydro governor models. This bug affected HYGOV, HYGOVD, HYGOVR, HYPID, HYG3, and HYGOV4 models after the patch dated February 2, 2022, which added a new feature of modifying the Hdam parameter to achieve the expected Pmech output at initialization.
August 16, 2022
Features and Improvements
- Difference Case Tool: Added support in the Difference Case tool for the DistributionEquivalent transient models. Also cleaned up some things with LoadModelGroups for the difference case tool as well.
- Transient Stability: Modified the REGC_C machine model to include a new parameter Vdip. The model will now freeze the PLL integrator state when the filtered terminal voltage is below Vdip.
- Transient Stability: Added special strings that can be used when specifying a list of fields to export from PowerWorld when using the SaveData, SaveDataWithExtra, SaveObjectFields, and SendToExcel script commands. This also impacts the various GetParameters-related SimAuto calls. These special strings act similarly to the special "All" available for any objecttype. The special strings and their behavior are as follows.
AllModelParams: exports all the model input parameters and references to objects necessary to define model
AllModelParamsPriKey: exports the primary keys for the objecttype and the same fields as AllModelParams
AllModelParamsSecKey: exports the secondary keys for the objecttype and the same fields as AllModelParams
AllModelParamsLabel: exports the label key for the objecttype and the same fields as AllModelParams
Examples:
SaveData("c:\temp\MyFile.aux", AUX, MachineModel_GENROU, [BusNum, ID, AllModelParams], []);
SaveData("c:\temp\MyFile.aux", AUX, MachineModel_GENROU, [AllModelParamsPriKey], []);
Both would result in AUX files with the following syntax
MachineModel_GENROU (BusNum,ID,Status,H,D,Ra,Xd,Xq,Xdp,Xqp,Xdpp,Xl,Tdop,Tqop,Tdopp,Tqopp,S1,S12,RComp,XComp)
{
12345 "1 " "Active" 1.2 0 0.004 3.2 2.29 0.211 0.25 0.153 0.088 9.5 2.9 0.05 0.05 0.216 0.446 0 0
12346 "1 " "Active" 4.22 0 0 1.73 1.6 0.285 0.8 0.2036 0.1 7.1 2 0.03 0.2 0.174 0.414 0 0
} - Oneline Diagrams: When defining filters for display objects, a device filter in the syntax of "
objecttype 'key1' 'key2' 'key3'" will now work when filtering the display object type by data objects of supported types. This means that a DisplayBus can be filtered by a particular Bus object as well as the other types of objects that are supported. This syntax was already supported by filtering a display object by its own type, i.e., DisplayBus by DisplayBus.
- Transient Stability: Using the script command TSWriteModels(FileName, DiffModifiedOnly) was opening a dialog asking what parts of transient stability information to save when it should not have been. This has been fixed so that this method only save transient stability Dynamic Model information.
Bug Fixes
August 12, 2022
Features and Improvements
- Contingency Analysis Tool: Added CriteriaCheckOnce field with RemedialActionElements. Set this to YES if the Model Criteria should only be checked once during the process of applying Remedial Action Elements in response to contingency actions (model criteria is evaluated with TOPOLOGYCHECK, POSTCHECK, or SOLUTIONFAIL status). If the criteria is not met, this action will not be implemented and the criteria will not be evaluated again. The Persistent field is ignored when this is set to YES. The action will not be implemented and the Model Criteria will not be evaluated again for a Model Criteria that is met but the Time Delay is greater than the Time Delays of other actions whose Model Criterias are also met. This option has no impact if the Model Criteria is not defined.
August 9, 2022
Bug Fixes
- General: In some situations when the recently opened files list in PowerWorld Simulator was cleared out when it should not have been. This has been fixed.
- Oneline Diagrams: Fixed an "Invalid pointer operation" error that could occur when opening a PWD file that contains substation, owner, or balancing authority objects with the same number key field as a different object type within these three object types. If choosing to open a oneline using either secondary key fields or labels instead of numbers, mis-identification of objects within these three types might occur if they have the same number. This can be fixed by opening the oneline with a case where the numbers for these types of objects on the oneline match the case and saving the oneline with this patch or later.
- Transient Stability: Fixed a bug an issues with Transient Stability Plots when saving the data using the Show/Save Selected Plot Data. The Save to... options were not working properly when saving certain data that is calculated from other fields such as Bus Voltage in KV. Also it wasn't working properly when the data contained RAM and Hard drive data in the plot. Those issues were corrected. This change also corrected the TSGetResults script commands and TSGetContingencyResults SimAuto function for the same issues.
- Transient Stability: Fixed error when using the "Copy All Charts and Title Block" when either the right or left memo contained multiple lines of text, then only the last line of text was being written to the image. This also impacted memos with multiple lines of text when exported to an image. The dialogs shown in the user interface were always correct, but the images are now also correct.
August 2, 2022
Bug Fixes
- Case Information Displays: When using Supplemental Data Objects and using the feature to "Inherits from Model Structure" to allow for example a Generator object to inherit a SupplementalClassification from the generator's bus, the code was very slow when definining 100s or 1000s of supplemental data objects. With 1000 counties defined when inheriting like this generator displays could takes 10s of second to refresh. This has been rewritten to make it much 1000s of times more efficient so no display refresh issues are noticed.
- GIC: Fixed access violation that would occur loading GIC time varying E field data after clearing GIC data. The data structures were not being reinitalized properly. This has been fixed.
- Transient Stability: In the Transient Stability Plot tool, the names of the plots and plot series was modified to eliminate the use of "\" character that may appear in them. In various other formats that a user may export the plot information to (such as a JSON file), the backslash character is a special escape character. To eliminate trouble users may experience with this, a "\" is eliminated and substituted with a "_". Example: "Gen_App Imp\R" will now look like this "Gen_App Imp_R"
- Transient Stability: Added to support to read/write PSS2C Stabilizer for PSSE dyr files.
July 28, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added script command to clear time varying electric field inputs: GICTimeVaryingElectricFieldsDeleteAllTimes.
This is equivalent to clicking 'Clear All Time Points' on the time varying electric field input tab. - GIC: Added script command to clear time varying electric field inputs: GICTimeVaryingElectricFieldsDeleteAllTimes.
This is equivalent to clicking 'Clear All Time Points' on the time varying electric field input tab.
July 26, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Modified the script command GICLoad3DEfield to have the parameter SetupTVSOnLoad as optional. It was not optional before.
GICLoad3DEfield(FileType, CoarseFile, SetupTVSOnLoad); SetupTVSOnLoad is an optional and is a YES/NO option and default is false.
- GIC: Modified the script command GICLoad3DEfield to have the parameter SetupTVSOnLoad as optional. It was not optional before.
GICLoad3DEfield(FileType, CoarseFile, SetupTVSOnLoad); SetupTVSOnLoad is an optional and is a YES/NO option and default is false.
- Transient Stability: Added pop up hints for options on the transient stability dialog.
- User Interface Dialogs: Added a caption in the Display/Column Options to include the name of the DataGrid. Now the Display/Column Options dialog caption will be like this: Display/Column Options: 'NameOfDataGrid'
- Oneline Diagrams: Modified the Select By Criteria feature for oneline objects so it can use the Area/Zone/Owner/DataMaintainer filtering.
- Transient Stability: Allow the directory to which TSR files are stored to be specified as blank from an aux file or script command.
- Transient Stability: TSClearAllModels script command will now delete Load Distribution Equivalents.
- Transient Stability: Added new "psuedo-energy" calculation for the Transient Result Analyzer to calculate an Energy for each TSResultAnalyzerModeMagAng and then the summation of this across all signals for the TSResultAnalyzerMode.
Bug Fixes
July 20, 2022
Features and Improvements
- Transient Stability: Added new CompLoadMon measurement model to transient stability.
July 19, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections):
- GIC: Modified the script command GICLoad3DEfield to include an option to setup the Time-VaryingSeries on Load. The script now looks like this:
GICLoad3DEfield(FileType, CoarseFile, SetupTVSOnLoad); SetupTVSOnLoad is not optional and is a YES/NO option and default is false. - User Interface Dialogs: Modified the Refresh Displays button the Window Ribbon tab to have a small icon of a grid. This makes adding the button to the Quick Access Toolbar look nicer.
- Available Transfer Capability (ATC) Tool: Added new comment in the ATC tool. If you choose an Area, Super Area or Zone as the buyer or seller, but that area doesn't have any generation, you will get an error saying "Seller 'the Seller Type' does not have any generation for direction 'direction name'" or "Buyer 'the Buyer Type' does not have any generation for direction 'direction name'". Right now though, it says "Seller and buyer are not in the same electrical island for direction Slack to AREANAME (AREANUM)"
- Contingency Analysis: Prior to running any contingency analysis or combo contingency analysis related functionality any islands created because of the option to "dynamically add/remove slack buses as topology is changed" will become permanent islands. This is to prevent the islands from being removed if a full contingency solution is done and the "dynamically add/remove..." option is not used. It is assumed that the topology that exists prior to any contingency analysis is the desired topology.
- Contingency Analysis: Fixed access violations that could occur when deleting CTGComboViolations that are island violations.
- PV and QV Curve (PVQV) Tool: Prior to running PV or QV analysis any islands created because of the option to "dynamically add/remove slack buses as topology is changed" will become permanent islands. This is to prevent the islands from being removed if the "dynamically add/remove..." option is not used with different sets of options. It is assumed that the topology that exists prior to any PV or QV analysis is the desired topology.
- PV and QV Curve (PVQV) Tool: It was possible that when loading PV or QV results from an aux file that the results would not be loaded correctly for the Base Case scenario if there also happened to be a contingency named "Base Case". Now always assume that the results are for the base case scenario with no contingency and that there should not be a contingency named "Base Case".
Bug Fixes
July 14, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Modified CalculateLossSense script command to include the new loss references options.
// CalculateLossSense (FunctionType,AreaSALossReference,IslandLossReference);
// NONE YES/NO EXISTING
// ISLAND LOADS
// AREA INJECTION GROUP NAME
// AREASA
// SELECTED - Case Information Displays: Added "powerfactor" as a generator field
- Contingency Analysis Tool: When using the auto-insert contingencies to insert by "bus groupings", we will now name the new contingencies created by the buses that remained connected but are on the edge of the grouping of buses being isolated. Previously we named the contigency after the buses that were on the edge but inside the group being isolated.
- Sensitivity Calculations: Added New References Options to Loss Sensitivity Dialog. Each Electrical Island will have the option to use Island Loads or Injection Groups as references. Areas and Super Areas will have the option to use the Area or Super Area Loss Reference.
- User Interface Dialogs: Modified the edit boxes showing the Branch MVA limits on the Branch dialogs to only show at most 7 significant digits for the MVA limits.
- Available Transfer Capability (ATC) Tool: Prior to running any ATC related functionality any islands created because of the option to "dynamically add/remove slack buses as topology is changed" will become permanent islands. This is to prevent the islands from being removed if a full contingency solution is done and the "dynamically add/remove..." option is not used. It is assumed that the topology that exists prior to any ATC analysis is the desired topology.
- Transient Stability: Modified the WTGAR_A and WTARA1 models so that they can initialize to an initial pitch that is negative. This is an unusual configuration for models but should be allowed.
Bug Fixes
July 6, 2022
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): There was a bug in the data check tool where the summary information on the owners table was incorrect. This was being caused by the improper inclusion of generators only used for internal modeling at an SVC bus. This has been fixed.
- Available Transfer Capability (ATC) Tool: When using the Full CTG Solution method with ATC and iterating on failed contingencies, it was possible to get into an infinite loop when the transfer level reached the minimun stepsize. This has been fixed.
- Case Information Displays: Showing any DataGrid objects in a User Defined Case Information Display was not working. This has been fixed.
- Sensitivity Calculations: Fixed "zero determinant in back substitution in row xxx" errors that can occur in a case that has SVCs when doing sensitivity calculations.
June 30, 2022
Features and Improvements
- Transient Stability: For a PlotSeries add two new options for a "Scale" and "Offset". When using these the Actual Value on the plot will be (y-Offset)*Scale.
- Power Flow Solution: Fixed a bug in the calculation of the maximum and minimum Mvar for a switched shunt configured as an SVC
Bug Fixes
June 27, 2022
Bug Fixes
- Available Transfer Capability (ATC) Tool: For ATC and linear contingency analysis significantly different results could be caused by small changes in option settings. This was traced to the LODFs being calculated as double floating point values but stored as single floating point values before they are used in the LODF cross matrix calculation that determines the impact on all outaged lines on all other outaged lines. This was fixed by storing these values as doubles. LODFs returned from standalone LODF calculations will still be stored as singles.
June 27, 2022
Features and Improvements
- Oneline Diagrams: Added an option in the Edit Mode right Click menu to move objects to Geographical Coordinates. The option works with Buses, Gens, Loads, Switched Shunts and Substations. The Gen, Loads and Switched Shunts will look for the terminal Bus Geographical Information. If the Bus, Terminal Gen Bus, Terminal Load Bus or Terminal Switched Shunt Bus do not have Geographical coordinates then it will look for the Substation Geographical Information (if the objects belongs to a Substation).
- Transient Stability: Fixed the LDTRPMON and CompLoadMon stability measurement models so that the do not sum LDELEC MW values incorrectly when the bus becomes isolated during the simulation.
- Transient Stability: Fixed listing of Measurement models in the Plot Designer when there are more than one kind of measurement model for the same object. For example a LDTRPMON and a CompLoadMon for the same area. Previously it was not listing all of them and this is now fixed.
Bug Fixes
June 22, 2022
Features and Improvements
- File Formats: Added ability to read/write the FuelType from the EPC file format. The integer codes in the EPC format are based on the WECC Data Preparation manual.
- File Formats: When writing out the ESURRY (exac1m in a DYD file) or REPC_C models to a PWB file these PWB files could be ready by patch versions of Simulator 22 from October 13, 2021 and later. However, when loading these PWB files into a patch of PowerWorld Simulator from October 6, 2021 or earlier the PWB file would fail to read. Todays patch fixes this so the PWBs written can be read by older versions of Simulator without trouble.
- Transient Stability: When writing out the ESURRY (exac1m in a DYD file) or REPC_C models to a PWB file these PWB files could be ready by patch versions of Simulator 22 from October 13, 2021 and later. However, when loading these PWB files into a patch of PowerWorld Simulator from October 6, 2021 or earlier the PWB file would fail to read. Todays patch fixes this so the PWBs written can be read by older versions of Simulator without trouble.
Bug Fixes
June 21, 2022
Features and Improvements
- File Formats: Modified reading of RAW file records for Bus, Gen, Load, Line and Transformer so that if an extra field is at the end of a record which is not expected, then we will try to read this in as a memo or label.
- General: Cleaning up where ObjectTypes appear in the folder structure on the dialog showing a list of all ObjectTypes.
- General: Modified option objects in the list of ObjectTypes so that they appear under the Options and Options By Value folder and then also under the respective tool if appropriate. For example the Contingency Options will appear under the folder Contingency\Options.
- Transient Stability: TSValidation object type is now available to return all validation messages. The Category field indicates if a message is an Error, Warning, or Info. This object type can be filtered and saved to file but nothing can be loaded back in.
- Transient Stability: TSState object type is now available to return all transient stability states. This object type can be filtered and saved to file but nothing can be loaded back in.
- Transient Stability: Added TSInitialize script command that will initialize the transeint stability solution. This can take one optional parameter CheckAlreadyInitialized that is NO by default. If YES the initialization will not be done if it has already been done. This script command is necessary if using the new TSState object type to return initial states through scripting.
- Transient Stability: Added TSValidate script command that will run transient stability validation.
June 16, 2022
Bug Fixes
- Time Step Simulation: In the Time Step Simulation tool, fixed a bug with the Injection Groups Input table. The bug was that when adding an Injection Group Input Column, the value shown for the MW was incorrectly multiplied by the system base thus showing an incorrect value. This was affecting the Timestep solution because it was using an incorrect value to change the injection group MW. This bug was fixed and the correct MW value is now shown in the column and is used for the timestep solution.
- Time Step Simulation: Fixed an obscure bug when setting IsXF=No using an AUX file. This should be OK, but if the branch still had a non-unity tap or non-zero phase, it could mess up the PWB save/load process. This has been fixed so that when IsXF is set to NO it will also change the tap to 1.000 and the phase to 0.0000.
June 14, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): With PWCaseInformation ObjectType added CountContingency field to show the total number of defined contingencies.
- Auxiliary Files (SCRIPT and DATA Sections): When choosing to Save to AUX on the Simulator Options Dialog, added a dialog that has check-boxes on it so you may choose which types of options to save. The choices are Solution, Environment, Simulation, Case Info, Custom Colors, Areva Import Label Specs, and Oneline Browser Custom Menu.
- Optimal Power Flow (OPF): When using the minimum control change objective function in the OPF, if the control had an initial condition that was a negative value, then the V-shaped cost function was being centered around 0.00 so that the control variable would prefer to be at 0.000. This had been done for Generator MW output many years ago, but probably should not have been done even for those. For phase-shifting transformer control variables however, this did not make sense. It has been corrected so that all control variables have a V-shaped cost curve with the minimum cost at the present operating point.
Bug Fixes
June 10, 2022
Features and Improvements
- Available Transfer Capability (ATC) Tool: ATC dialog will now update if an aux file is loaded from any location. Previously it would only update if an aux file was loaded using the Load Settings button on the dialog.
- Available Transfer Capability (ATC) Tool: Added ATCWriteScenarioMinMax script command that will save a file to report the minimum or maximum limiter based on either the Transfer Limit or one of the ATC Extra Monitor fields and to group the results by particular ATC Scenarios and include particular scenarios in the calculation.
- Oneline Diagrams: Added a new right-click option on oneline display objects to bring up the model explorer and navigate to the object.
- Transient Stability: Fixed access violation bug that was introduced in May 2022 when using the "Convert CMPLDW and CMLD Models to CompLoad".
Bug Fixes
June 9, 2022
Bug Fixes
- Transient Stability: Fixed bug introduced in June 8, 2022 patch with running transient stability simulation with an REPC_B plant controller model defined.
June 8, 2022
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added new feature on ATC dialog to report the minimum or maximum limiter based on either the Transfer Limit or one of the ATC Extra Monitor fields and to group the results by particular ATC Scenarios and include particular scenarios in the calculation.
- Transient Stability: Added the ability to read from a DYR file a PLNTBU1, REAX3BU1, REAX4BU1, SYNAXBU1, FCTAXBU1, and SWSAXBU1 models and convert them into an REPC_B plant controller model which controls multiple generators. PowerWorld Simulator will also write these models back out to a DYR file as this was added
- Transient Stability: Cleaned up the look of how DYR files are written to remove unnecessary trailing 0s from numbers and remove lots of extra spaces in them. Each records is also written on a single line of text now instead of multiple lines.
- Simulator Automation Server (SimAuto): Fixed WriteAuxFile SimAuto function.
(1) Passing "ALL" for the fieldlist is now case insensitive and means to return all fields for the objecttype
(2) The ToAppend field now works as one would expect; ToAppend = True means to append to an existing file, and ToAppend = False means to overwrite an existing file. This parameter has no impact on a file that doesn't already exist.
Bug Fixes
June 4, 2022
Features and Improvements
- Case Information Displays: Added several new fields for showing geographic information for result objects such as ViolationCTG, LimitViol, TSResultEvent, TSLimitViolation, TSResultAnalysisSignal, TSResultAnalysisViolation.
Fields will show values for Geography-related fields such as Branch.LineLength, and various Latitude/Longitude fields for objects for which results are being reported. - Case Information Displays: Added Latitude/Longitude fields for the From and To Bus of a VSCDCLine object
- Transient Stability: Added a new user input field for a TSContingencyElement called IncludeInTripped. Setting this field to YES means that any generation or load MW that is directly opened by the action will include this MW amount as part of the "Summary Results for for Tripped Generation and Load" which is kept track of as a result of a TSContingency. By default the load or generation tripped specifically by a TSContingencyElement is NOT included as part of this summary information. Note that TSContingencyElement actions to open devices such as branches which then result in generation or load becoming disconnected will always be included in this summary information. Users explicitly modeling remedial action or relay type events as part of a TSContingencyElement may find it useful to set this to YES so reporting reflects what they want.
- Transient Stability: Generation and Load MW that gets tripped by a TSContingencyElement acting directly on an InjectionGroup can now be included in the Summary Results for Tripped Generation and Load, but will obey new IncludeInTripped field.
- Contingency Analysis: The contingency element identifier for a branch that is part of a multi-section line will no longer contain the section number for OPEN or CLOSE actions. This section number with OPEN and CLOSE actions has always been ignored when loading an aux file and this resulted in the actions appearing different if comparing based on the identifying string. For OPEN and CLOSE actions, the section number does not matter because the action is applied to all sections in the multi-section line.
- Oneline Diagrams: On the Zone Oneline Object dialog, when opening the dialog the Name combobox was not being properly populated. This has been fixed.
- Transient Stability: Modified documentation of Vramp and Cramp parameters of the CDC4 and CDC6 type DC Line models to reflect that they are in the units of pu/sec.
- Transient Stability: When restarting a DC line in transient stability after inverter bypassing, the units on Vramp and Cramp were not being treated properly and the DC line would restart at an extremely slow manner which was not correctly. This has been fixed. Note: the restart after rectifier blocking was correct. Now both Vramp and Cramp ramping for both inverter bypass and rectifier blocking is correct.
Bug Fixes
May 26, 2022
Features and Improvements
- PV and QV Curve (PVQV) Tool: Adding feature when automatically determine the vertical axis scale to force the Minimum value to be greater than the Minimum specified. This allows the automatic scaling to ignore values that are zero for example. Also added similar feature to force the Maximum value to be less than the Maximum specified.
- Transient Stability: Adding feature when automatically determine the vertical axis scale to force the Minimum value to be greater than the Minimum specified. This allows the automatic scaling to ignore values that are zero for example. Also added similar feature to force the Maximum value to be less than the Maximum specified.
- Power Flow Solution: In an unusual situation when solving a power flow with an SVC type svsmo3 sitting on it's current limit, the power flow may not converge. This has been fixed.
Bug Fixes
May 18, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Adding new script commands for inserting display objects on a oneline using an AXD script command.
AutoInsertAreas(MapProjection, InsertIfNotAlreadyShown, InsertSelected);
AutoInsertInjectionGroups(MapProjection, InsertIfNotAlreadyShown, InsertSelected);
AutoInsertOwners(MapProjection, InsertIfNotAlreadyShown, InsertSelected);
AutoInsertZones(MapProjection, InsertIfNotAlreadyShown, InsertSelected); - File Formats: Bug in displaying incorrect log message when loading an otgd file for transient stability. When loading an otgd file with the old format of expressing the commands, if the bus in a branch didn't exist in the case it was displaying an incorrect log message about "Invalid time" instead of the wrong bus message. This error was fixed and the correct message will display in the log.
- Oneline Diagrams: Fixed bug on the Owner Display Object dialog which could cause the name listed on the dialog to be incorrect.
Bug Fixes
May 17, 2022
Bug Fixes
- Transient Stability: Fixed error in the derivative control for the H6E governor model. The sign on the Kd was incorrect.
May 16, 2022
Features and Improvements
- Oneline Diagrams: Added new features under the Auto Insert drop-down on the Draw tab to automatically insert Area, Zone, Owner, and InjectionGroup display objects on a oneline diagram. The locations will be determined by look at the new Latitude/Longitude values for these objects now available on the case information displays.
May 13, 2022
Features and Improvements
- Case Information Displays: Added new case information fields to show Latitude, Longitude, Latitude String, and Longitude String for several objects including: Area, Zone, Owner, InjectionGroup, Contingency, RemedialAction, and Interface. Fields will return the average latitude/longitude of the objects contained inside them.
- PV and QV Curve (PVQV) Tool: PV tool options are now stored with the PWB file so it no longer makes sense to initialize the tool with options based on the power flow solution. This was only being done with the option to enforce generator MW limits during injection group ramping, but it was causing confusion because it was overriding the option as it was set with the PVCurve_Options object.
Bug Fixes
May 10, 2022
Bug Fixes
- Transient Stability: Fixed access violation which could occur when using the CHATGY DC Line transient stability model and not defining all 4 CSP branches.
- User Interface Dialogs: When opening a case from command line or by double clicking on a file type that is associated with Simulator, it was possible that the case would not load without first making the welcome window have focus. This has been fixed.
May 2, 2022
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added button on ATC dialog to Store Initial State.
- Contingency Analysis Tool: When sorting the Contingency object type by the Violations field (number of violations), any contingencies that have been processed and are Unsolved will be treated as the highest value in the sort order so that when sorting in descending order they will always appear at the top. They will always appear at the bottom when sorting in ascending order.
- Contingency Analysis Tool: When sorting the Contingency object type by the count of any type of violation, Unsolved will be treated as the highest value in the sort order so that when sorting in descending order they will always appear at the top. They will always appear at the bottom when sorting in ascending order.
- Difference Case Tool: Fixed several instances of invalid lookups into the list of lines in a MSline. This was happening in difference mode, when the list of lines is not always valid.
Bug Fixes
April 28, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added ability to write ContourPixel and ContourDataPoint objects out to an AXD file. ContourDataPoint objects have information about the data point used to create the contour image. ContourPixel contain information about all the x/y coordinates the represent the contour image.
- Available Transfer Capability (ATC) Tool: In ATC when iterating on all limiters to determine the individual limiters to iterate on when using one of the iterated methods, the analysis will stop if a reserve limit is found because there are no available participation points for calculating the linear step size. Previously the analysis would continue on to iterating on individual limiters, but the results would be the same for all limiters because no additional stepsize could be found because no available participation points would exist for any individual limiters.
Bug Fixes
April 27, 2022
Bug Fixes
- Available Transfer Capability (ATC) Tool: In ATC analysis fixed a bug that would not reset a transfer limiter that was set to POWERFLOW_DIVERGENCE because the full transfer amount could not be achieved in the initial step when iterating and ramping without actually solving the contingency when iterating on a single limiter. A power flow divergence that happens in this step could be reset to NO if the contingency solves and ramping is able to be done after solving the contingency. Setting to NO was not always being done.
- Difference Case Tool: Fixed bug in DiffCaseWriteCompleteModel script command when storing changes in the GenVarLim objects to an EPC file which was causing an access violation.
- Transient Stability: Additional corrections with Results Analyzer to keep track of data from both RAM and Hard-Drive because end-times could potentially be different.
April 26, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Allow the SolvePowerFlow script command to be specified with empty parentheses and no parameters. This will use all of the default parameters the same as specifying the command without parentheses. This also allows the SolMethod to be specified as a blank string.
- File Formats: Previously PowerWorld would write cmpldw model defined in PowerWorld at an aggregation level such as Bus, Load Model Group, Area, Zone, or Owner, we would always write out cmpldw models for individual load objects because this is the only thing that the DYD file supported. The DYD file now supports writing out a special "_cmpldw" model for load model groups, areas, zones, and owners, so we will write out these special "_cmpldw" models to DYD files.
- Power Flow Solution: For cases with bad input data such that generators at the same bus have different voltage setpoints, PowerWorld would just take the last generator's setpoint value. This has been modified so it will take the setpoint of the generator with the largest (MvarMax - MvarMin) value instead.
- Transient Stability: In Result Analyzer when the end user end time is greater than the available time in the results it was getting more modes because it was assuming the time step was the end time the user selected. This is now corrected and only the data points until the available data end time is used.
Bug Fixes
April 20, 2022
Features and Improvements
- File Formats: Modified the feature to "Save Known Fields in HDB Pattern File" so that it now writes 4 files
c:\FilePath\FileName.txt : list of object/fields for exporting a solved case
c:\FilePath\FileNameCTG.txt : list of object/fields for exporting contingency definitions
c:\FilePath\FileNameRAS.txt : list of object/fields for exporting the RAS definitions
c:\FilePath\FileNameHdbexport.txt : Text file describing how to call the hdbexport command
The FileNameHdbexport.txt is the new file that was added in this patch. - Available Transfer Capability (ATC) Tool: At end of ATC run, TransferLimiters will be sorted from low to high transfer limit, contingency with any base case limiters coming first, and then limiting element. Previously the limiters were not sorted at the end of the calculations, which could result in the limiters being out of order if using the iterated methods. Limiters were being sorted when loading from an AUX or PWB, and this will make the result order consistent immediately after a run and when loading from file.
- File Formats: Fixed an access violation saving multi section lines to the EPC format in difference mode. In difference mode, the list of lines in the ms line can be nil and they were still being accessed. This has been fixed.
- Power Flow Solution: When using the option to "Use Loss Factor For DC Line tielines", it was possible for the metered direction of the metered point of the line to be handled incorrectly and thus mess up the ACE calculation and area interchange. This has been fixed.
- User Interface Dialogs: Fixed problem with the Set Generator Participation Factors tool and the SetParticipationFactors script command that would not set the correct generators when setting by area or zone.
Bug Fixes
April 12, 2022
Features and Improvements
- Available Transfer Capability (ATC) Tool: On the ATC Dialog allow using an aux file to set the option to "Analyze Multiple Scenarios" rather than always forcing the option to be checked if multiple scenarios are defined.
- Auxiliary Files (SCRIPT and DATA Sections): Changed the CreateNewAreasFromIslands script command so that it prints log messages rather than generate an error in the event that no new areas are created. This could happen because of an error in the case (multiple areas spanning multiple islands) or because there's nothing to do.
- GIC: Made change to code that detects GSUs to more correctly handle three-winder GSUs. Now only the flow on the highest winding branch is reported as the transformer's flow. This will be correct if the GSU is truly radial, which is the focus of this code
Bug Fixes
April 8, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added script command CreateNewAreasFromIslands to allow script command access to the Tools->Other->Create New Areas from Islands functionality.
April 7, 2022
Features and Improvements
- Transient Stability: Added a message when changing, setting and ramping a load in transient stability. The message will tell the user that the Mvar also change and look our web help for more info.
- Transient Stability: Added support to read and write ESDC2C transient model from a dyd file.
- Fault Analysis: Fixed a bug calculating the phase currents on the TO side of a Delta - Grounded Wye transformer when the user put in ground impedance values for RG2 and XG2. Previously the calculation specifically for this transformer configuration was incorrectly using the RG and XG ground impedance values on the FROM side of the transformer when calculating the TO side phase currents.
- Oneline Diagrams: Fixed a bug where gauges were not showing anything for owners if the owner only had loads assigned but no buses. Changed it to work the same as for areas, etc., that the gauges will show the load value for an owner group, even if only loads are part of the owner.
- Transient Stability: Bug Fix for UEL1 model.
- Transient Stability: Fixed a bug with WTGPT_A in where the Pitch was miscalculated if the Generator was controlled by a remote plant.
Bug Fixes
April 1, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): SetData and CreateData script commands now support referencing a model field using the "&Objecttype 'key fields' concisename:digits:decimals" syntax when specifying the values of key fields used for identifying objects. Previously this syntax was only supported when specifying the values of non-key fields.
March 29, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Allow multiple injection groups to be selected for injection changes in the LineLoadingReplicatorCalculate script command. To specify more than one injection group, just include a comma delimited list of the injection group names instead of a single injection group within the bracketed injection group parameter.
LineLoadingReplicatorCalculate([Flow Element], ["IGName1", "IGName2", "IGNameN"]...); - Case Information Displays: Fixed "List index out of bounds" error that could occur when right clicking on a case information display outside the table of records.
- Oneline Diagrams: Fixed potential exception when cancel is selected when creating a GDV display.
Bug Fixes
March 24, 2022
Features and Improvements
- File Formats: Added support to read and write GENQEC, PSS2C, OEL3C, and UEL1 transient models from a dyd file. The model were already available in PowerWorld.
March 16, 2022
Bug Fixes
- QV Curve Tool: When running a QV curve at a bus, SVCs that are remotely regulating that bus are now turned off control. SVCs should be treated the same as generators that are remotely regulating the curve bus and need to be turned off control to not conflict with the fictitious generator. When a contingency or base case cannot solve and the fictitious generator is used to try to make them solve, switched shunts and SVCs at the curve bus are now turned off control and SVCs that are remotely regulating the curve bus are turned off control. These need to be turned off so that they do not conflict with the voltage setpoint of the fictitious generator.
- Transient Stability: Added an Event message for DISTRELAY models to say which Zone number activated the relay.
- User Interface Dialogs: Fixed a bug related to equivalencing and selecting buses by area, zone or substation with the n number of neighbors option.
March 8, 2022
Features and Improvements
- Case Information Displays: Added a new field field MeteredBus to the TieLine fields for the Area and Zone tieline tables. This shows the integer bus number of the metered end of the tieline.
- User Interface Dialogs: Increased the number of decimal places to 6 when showing the x,y values in the zoom dialog in lon, lat values.
March 4, 2022
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): In 1/19/22 patch the following fix was made: Modified the error message that appears when loading an aux file and an object cannot be found. Some objects have more than three key fields and the additional key fields were not being included in the error message. This could create a list index error if not all of the additional key fields were present in the aux file data section. This has been fixed.
- Time Step Simulation: Fix so the time step simulation plots show by default the x-axis labels using the date and time format.
- Transient Stability: There was a bug preventing the transient plant controller PF1, PF2, VAR1 and VAR2 from actually changing the VREF in an exciter. This was fixed.
March 2, 2022
Features and Improvements
- Case Information Displays: Added special right-click option at the top of the case information local menu to "Follow link in browser". This will only be an option if the first 7 characters of the cell clicked on are http:// or if the first 8 characters are https://. If those are not the first 7 or 8 characters then the option is not visible. This will work on any cell on a case information display.
- Case Information Displays: Modified so that Bus View is the first menu item in the object specific sub-menu on Case Information Displays
- User Interface Dialogs: Add buttons to the Substation and Bus dialogs in both Edit and Run mode on the Geography tab to "Open Google Maps". This button will automatically launce the default browser on the computer and open the Google maps website to the latitude/longitude coordinate on the respective dialog.
- Power Flow Solution: Fixed a bug when adding more than one VSC DC Line to a bus. It was only solving one line instead of all the VSC DC Line. Also the bug was preventing from seeing the VSC DC Lines in the BusView.
- Power Flow Solution: When determining the Setpoint Voltage Tolerance to use with generators regulating voltage, only generators with an available AVR range can be used for selecting the tolerance. If no range is available the tolerance will be 0.
Bug Fixes
February 25, 2022
Features and Improvements
- Contingency Analysis Tool: Advanced filtering of rows is now supported for Contingency Violation Matrices.
- Transient Stability: A new transient stability script command was added. The script command is to Run the result Analyzer. It has the following name and format: "TSRunResultAnalyzer(Contingency Name);" If the Contingency Name is empty it will run the Result Analyzer in all the contingencies. Also if the script is entered as "TSRunResultAnalyzer;" it will run the Result Analyzer in all the contingencies.
- Available Transfer Capability (ATC) Tool: Fixed an access violation with ATC. The error was happening when an Interface didn't had a branch contingency element and was calculating the OTDFs. This was causing an access violation and that is fixed in this patch.
- Case Information Displays: Model Criteria field was available with ContingencyPrimaryElement object type when it isn't supported. This has been fixed.
Bug Fixes
February 23, 2022
Features and Improvements
- User Interface Dialogs: Added saving the shortcut definitions to the registry when the shortcuts dialog is closed, rather than waiting until the program is closed to write them to the registry.
- Available Transfer Capability (ATC) Tool: ATC Scenario change objects cannot have custom expressions or custom string expressions created for them. They do allow the use of the expressions that belong to the object type that is being changed. Organized the list of available fields for these objects to make this clear.
- Case Information Displays: Using a CalculatedField defined for a InterfaceElement and applying it to an Interface was not working properly. This has been fixed.
- Oneline Diagrams: Generator rotor symbols were not properly rotating when animating a oneline diagram. This has been fixed.
- Optimal Power Flow (OPF): When choose whether to enforce limits on an interface in the OPF solution, we ensure that at least one element of the interface is configured to be enforce limits and that at least one device belongs to an area which is on OPF control. This check was also considering the status on branches that were assigned as a BRANCHOPEN or BRANCHCLOSE event. We have modified so that the checking of status on BRANCHOPEN and BRANCHCLOSE devices is no longer considered.
Bug Fixes
February 17, 2022
Features and Improvements
- User Interface Dialogs: Modified the Long Line Voltage Profile tool to also show the Current [Amp] profile across the length of hte line as well.
- File Formats: Fixed a bug writing out the convergence tolerance in version 34 and later RAW files
Bug Fixes
February 15, 2022
Bug Fixes
- Time Step Simulation: Fixed bug introduced in Oct 22, 2021 patch when using Copy/Paste of data from Excel into the Time Step Simulation table for Generator MW fields. The Oct 22, 2021 patch fixed a bug with pasting into the MaxMW tables, but this broke pasting in the MW table. Now both tables will work appropriately.
February 14, 2022
Bug Fixes
- File Formats: When writing out RAW files containing an Switched Shunt with an svsmo3 type, it is written as a FACTS device to a RAW file. This was not roperly handling the MaxMvar and MinMvar written to the RAW file.
- Transient Stability: When running Distributed TS, if a contingency does not solve, the ReasonNotSolved is added to the Simulator log.
- Transient Stability: Fix a bug with option to "Include Category in Plot Name" as a prefix for the Transient Stability plot names when auto-saving the plots. It wasn't working with saving into a pdf. This was fixed.
February 9, 2022
Features and Improvements
- Transient Stability: Modified the option under the Stability Case Info drop-down on the Add-ons Ribbon Tab to expend the feature to "Convert CMPLDW and CMLD model to CompLoad". Previously it did not convert the CMLD model into CompLoad models with components but now it will do that along with the CMPLDW models.
- File Formats: Fixed a bug writing the transformer data to PSSE GIC data file
- Transient Stability: Fixed error in the use of the three-phase induction motor model MOTOR_CMP when used as a load component in the CompLoad model. The under-voltage tripping and reconnecting blocks were not being properly applied so that tripping and reconnecting did not occur. This has been fixed.
Bug Fixes
February 8, 2022
Features and Improvements
- Transient Stability: When saving Transient Contingencies as an Aux file it will also save the Transient Contingency Elements. This was not done before when saving from the Multiple Contingency table.
- File Formats: When reading a contingency OTG file, if there was a BUS or a SECDD command it was adding a contingency element that was skipped because it was added incorrectly. Now the bus command is going to be added as an unlinked element event so the user will now that we do not support that command. The SECDD command will add the correct branch contingency element event and will be solved (not skipped) during the contingency analysis run.
- Transient Stability: The column for showing the active relay models for a Load record was always showing blank. The load relays were there and active, but just not showing properly in the summary table. This has been fixed.
Bug Fixes
February 7, 2022
Features and Improvements
- Transient Stability: Added an option to "Include Category in Plot Name" as a prefix for the Transient Stability plot names when auto-saving the plots. If the Category is blank and the options is selected and "_" will appear in the plot name.
- Oneline Diagrams: Removed the ability to save a BusView or SubView as a PWD file. This serves no good purpose, and can confuse a user and lead them to accidentally save a simple BusView on top of their existing PWD file by accident.
Bug Fixes
February 2, 2022
Features and Improvements
- Difference Case Tool: Added a Verify Computers button to each distributed computation tool dialog box.
- Transient Stability: Modified the hydro governor models HYGOV, HYGOVD, HYGOVR, HYPID, HYG3, and HYGOV4 models when initial state limit violations occur because the Pmech output is higher than the combination of the inputs of Hdam (or H0), qnl, At, and the nonlinear Gate to Pgv block are able to achieve. When using the initial limit violation option to "Modify Limits and Run", PowerWorld will now calculate a the higher value of Hdam necessary to achieve the Pmech output. Previously PowerWorld would change the At (turbine gain), but discussions with customers indicate it is more appropriate to modify Hdam instead.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug in RestoreState script command that would not allow the WhichState parameter to be enclosed in double quotes.
- Case Information Displays: Fixed error with Area, Zone, BalancingAuthority, and Substation objects. General fields like Custom Strings, Integers, Selected, and field associated with specifying what to store in transient stability simulations were not showing properly in case information displays. This error was introduced in an early January 2022 patch, but is now fixed. Not that old files would have functioned fine, just showing these values in case information displays or writing them to AUX files would have resulted in the fields appearing as blank even when they were populated with data.
- Oneline Diagrams: Fixed contouring bug in which the code could hang when contouring multiple points at the same location (like with generator data).
- Transient Stability: Fixed bug in CSTCNT switched shunt model which was preventing it from regulating the voltage at a remote bus. The model was instead always regulating the local terminal bus voltage.
- Transient Stability: When performing a validation check for most values in transient stability against a minimum limit PowerWorld had a 0.000001 tolerance we checked against. For some situation this tolerance was too small. For example a user may run auto-correction against time constants the are required to be 4 times the 0.25 cycle times timestep which we would calculated as 1/240 * 4 = 0.0166666667 seconds. If a time constant was smaller than this we would round it up to exactly that time constant. However if the user then changed the contingency to use a timestep of 0.004167 seconds (we store timestep in second out to microsecond precision), then the required minimum timestep was 4*0.004167 = 0.016668 seconds. That means that the previously auto-corrected timestep was no "too small" because 0.0166666667 < 0.016668. Thus the value is too low by 0.0000013333 seconds which is just slighly above the old tolerance we have. This has been changed so the tolerance is now 0.05% of the limit, so in this case the tolerance if 0.0166666667*0.0005 = 0.0000083333 (so just over 8 microseconds). This slightly larger tolerance will scale appropriately for all situations.
Bug Fixes
January 28, 2022
Features and Improvements
- Contingency Analysis Tool: PowerWorld reads ContingencyElement from AUX files if the Object referred to by the ContingencyElement is not found, then a special "Unlinked" ContingencyElement is created and can be viewed in the user interface. For users not familiar with this feature however a warning message in the log is a helpful reminder to go look for these unlinked elements. These log messages have been added.
- Contingency Analysis Tool: Added log message when a ContingencyElement becomes unlinked because the object to which it was referencing was deleted.
- Distributed Computation: When using Distributed Computing tools, PowerWorld does verification to ensure the machines listed are configured to support distributed computer. When that verification resulted in a computer that was not available, the error messaging was confusing. This has been improved.
- GIC: Fixed saving GIC data to PSSE format so that it correctly uses Area/Zone filters when saving, if the option is selected. Also changed the option to say it uses the filters when saving GIC data to PSSE format only. We do not apply area/zone filters when reading data from PSSE GIC file.
Bug Fixes
January 25, 2022
Features and Improvements
- Transient Stability: When selecting a Transient Contingency to Skip the entire row fields will grays out. This will help the user visually identify the skipped contingencies.
- Difference Case Tool: When choosing to Set Present as BaseCase, VSCDCLine objects were not properly storing the ownership designations in the BaseCase. This means they always showed BaseCase ownership as empty strings, which meant that the difference case always showed a change in ownership.
- Transient Stability: Fixed a bug with SimAuto function TSGetContingencyResults. If the case was storing the results into Hard Drive the function wasn't returning any results. That problem is fixed and now it will return the requested results.
- Transient Stability: Fixed a bug when Calculating Effective Impedance from Sequence Networks in the transient stability event for buses and branches. The issue is when the Ymatrix created with the sequence data is singular then it was creating an infinite impedance causing the simulation to stop. This has been fixed.
Bug Fixes
January 10, 2022
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added Length function that can be used with expressions. This function takes a string as a parameter and returns an integer.
- Case Information Displays: Added Case Path as an available field for the PWCaseInformation object type.
- Case Information Displays: Added Bus and Bus Group fields to show the generator MW range (total, up, down). There are three options: either 1) the AGCable generators that are online, 2) all online generators, 3) all generators.
- Case Information Displays: Added fields to show switched shunt values aggregated at the bus, area, zone, substation, and superarea level.
- GIC: Added Bus GIC field to show the GIC related losses allocated to the bus. These include the losses from the implicit GSUs and the other transformers. To avoid double counting the explicit transformer losses, the losses are allocated to the transformer's from bus only. Modified in v23 and v22.
- GIC: Added showing GIC electric field magnitude and angle on the substation dialog. Also, the code now transfers back the substation electric field magnitude and angle from TS (this would mostly be used for EMP analysis).
- GIC: In GIC I modified the code that calculates the substation and line electric field values for the non-uniform fields to be more efficient. This should make the Setup Time Varying Series function faster (which is called whenever a b3d file is loaded).
- Oneline Diagrams: Added support for GDV two field rectangle objects. These are similar to the kites, except using rectangles. The objection are either top and bottom values, or left and right values.
- Transient Stability: Added new injection group command to open or close all devices in the injection group.
- Transient Stability: Added TS Interface Open and Close commands. These commands open or close all the branches in the interface.
- Transient Stability: Added the ability to make plots from Result Analyzer Signal Violations. See "Make New Plot..." in the right-click local menu.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that would not identify CustomExpressionStr objects with the correct key field identifier. The result was that multiple string expressions for the same object type would all have the same key field resulting in only one being created when loaded from an aux file.
- File Formats: PSSE RAW file generator records will be written out with WMOD = 1 when the FuelType =SUN (Solar) OR Unit Type = PV (Photovoltaic) within Simulator
- GIC: Added read/write support for the EMP E1 fields (so they don't get lost in load/saving with v22)
- GIC: Added code to prevent an exception error when the GIC Form is close while the transient stabilty simulation is running.
- Oneline Diagrams: Fixed bug when trying to delete points from the Contour Symbol Dialog.
Bug Fixes
December 21, 2021
Features and Improvements
- Case Information Displays: Add a right-click option on all case information displays called "Show Field Descriptions". When clicking on Show Field Descriptions, a dialog will appear listing all the fields that are presently shown as columns in the case information display, along with the description of those fields. This is the same description that appears in the hover hints when moving the mouse over the column headers as well as the string that appears in the Export Case Object Fields option from the Window Tab in Simulator.
- Transient Stability: Added a button on the Model Explorer when showing transient stability models called "Parameter Descriptions". This button is adjacent to the "Show Block Diagram" button that was already there. When clicking on Parameter Descriptions button a dialog will appear listing all the dynamic model input parameters for the class of model being shown, along with the description of those fields. This is the same description that appears in the hover hints when moving the mouse over the column headers as well as the string that appears in the Export Case Object Fields option from the Window Tab in Simulator.
- Transient Stability: Modified the CMLD and CMLPDW model so that if a loading factor for a motor is set as 0.0, then we simply interpret as 1.0 instead. 0.0 causes divide by zero errors which don't make sense.
- Oneline Diagrams: Fixed various issues with being able to update generator field objects on a oneline using an AXD file and selecting specific generator display fields based on the field that they are displaying using the Select by Criteria tool.
- Oneline Diagrams: Fixed a bug specifying the most commonly used load display fields when using the Select by Criteria tool.
- Oneline Diagrams: Fixed a bug specifying the most commonly used transformer display fields when using the Select by Criteria tool.
- Transient Stability: When storing to result to RAM, if a plot contains a value Simulator will automatically store that value to RAM. This was not working properly for the VSCDCLines so that these results were not stored to RAM automatically. One could choose to store them in the Result Storage options but they were not automatically stored. This has been fixed.
- Transient Stability: Fixed defaults for the CMPLDW load model -- the values for the single phase motor model were being set as though it was a three-phase model.
- Transient Stability: Bug fix for DISTRELAY line relay model to prevent relay operation during load encroachment.
- Transient Stability: Fixed initialization issue with OEL4C
Bug Fixes
December 16, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added script command PVDataWriteOptionsAndResults("filename", AppendFile, KeyField) that will write out all options and results associated with the PV tool to an auxiliary file. This writes out the same information as PVWriteResultsAndOptions except that it will ALWAYs use the concise variablenames and headers and use DATA sections instead of SUBDATA sections.
- Auxiliary Files (SCRIPT and DATA Sections): Added Use Concise Format checkbox to the PV saving options dialog when saving to an auxiliary file using the Save Auxiliary button on the PV Curve tool dialog. This will always use the concise variablenames and headers and use DATA sections instead of SUBDATA sections.
- Auxiliary Files (SCRIPT and DATA Sections): Added script command QVDataWriteOptionsAndResults("filename", AppendFile, KeyField) that will write out all options and results associated with the QV tool to an auxiliary file. This writes out the same information as QVWriteResultsAndOptions except that it will ALWAYs use the concise variablenames and headers and use DATA sections instead of SUBDATA sections.
- Auxiliary Files (SCRIPT and DATA Sections): Added Use Concise Format checkbox to the QV saving options dialog when saving to an auxiliary file using the Save button on the QV Curve tool dialog. This will always use the concise variablenames and headers and use DATA sections instead of SUBDATA sections.
- Auxiliary Files (SCRIPT and DATA Sections): Added parameter AppendFile to the QVWriteResultsAndOptions("filename", AppendFile) script command. This is an optional parameter that can be omitted and will be YES by default.
- Auxiliary Files (SCRIPT and DATA Sections): When saving ATC settings to an aux file either using script commands or the Save Settings button on the ATC dialog, any injection groups that are used with transfer direction definitions will also be saved.
- Available Transfer Capability (ATC) Tool: Added TransferLimiter field called Report Limit that is YES for the limiter that has the lowest overall Trans Lim value if there are no limiters that were iteratively found or the lowest Trans Lim value for the limiters that were iteratively found. This is the same limiter that is reported in the results table for multiple scenarios.
- Case Information Displays: For Switched Shunt Case Information Displays added AutoControl field as a default column
- Time Step Simulation: Time Step Simulation input now has an option to input a values are the scaled based on a combination of the initial value and the variation in another (selected) column. A common example is scaling load in which the desire is to make the load conforming say between areas.
- Transient Stability: Fixed a bug with VTGTPAT timers. If the Relay Pickup Time (RelayTP) is more than 30 seconds there were some errors in the timer. This was fixed and now the relay will act in the correct time.
Bug Fixes
December 9, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): PVWriteResultsAndOptions script command will now save interfaces and injection groups that are part of the PV options or part of remedial action dependencies. Objects that are dependencies of contingency and remedial action definitions will also be saved. These changes also apply to Save Auxiliary button on the PV Curve dialog.
- Auxiliary Files (SCRIPT and DATA Sections): QVWriteResultsAndOptions script command will now save objects that are dependencies of contingency and remedial action definitions. These changes also apply to Save... button on the QV Curve dialog.
- Power Flow Solution: On the Power Flow Solution Options, Advanced Options page, added an option in the Control (Middle) Loop Options called Var Limit Backoff Voltage Tolerance (VarLimitBackoffVtol). This parameter had always been hard-coded to 0.00005 per unit previously. This is the tolerance on when to backoff generator Var limits based on how far the regulated the bus voltage is beyond the voltage setpoint. This controls the transition from a PQ back to a PV bus (backing of a Var Limit).
- Time Step Simulation: In the Time Step Simulation there is now a local-menu item to delete all the input columns. This is a common operation, and the new commands saves the time of having to select all the columns.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed issue with editing the Weight field for InterfaceElement when loading from an AUX file. This field was not being updated when loaded from an aux file.
Bug Fixes
December 8, 2021
Features and Improvements
- User Interface Dialogs: General File Browser added support for searching for *.tsb files.
December 7, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Renamed ATCWriteAllOptions script command to ATCDataWriteOptionsAndResults to better reflect what this is actually doing - writing both options AND results while using the concise format without SUBDATA. ATCWriteAllOptions can still be used as a legacy name.
- Transient Stability: Added transient result events for the REEC_D model when it blocks and unblocks the machine model.
- Transient Stability: Changed the name of the model InductionMotor3P_A_Beta to instead by INDMOT3P_A. PowerWorld will still read old models with the name InductionMotor3P_A_Beta in as INDMOT3P_A however.
- Transient Stability: Fixed an error in that could occur when using the REEC_D electrical control model in combination with the REGC_B machine model when the REEC_D model blocks the machine model.
Bug Fixes
December 6, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Updated the removed duplicate interfaces feature to handle limits. Previously, the interface limits of the first interface encountered in a series of duplicates were kept. This has been updated so that the limits will be updated to keep the most restrictive set of interface limits.
- Case Information Displays: Updated the removed duplicate interfaces feature to handle limits. Previously, the interface limits of the first interface encountered in a series of duplicates were kept. This has been updated so that the limits will be updated to keep the most restrictive set of interface limits.
- Case Information Displays: Added new available fields for an Island to show DistMW and DistMvar across the island.
- Case Information Displays: Added the DistMW and DistMvar as default columns on the Case Information Displays for Areas and Zones.
- Transient Stability: Modified plots so that various colors can be specified to make it easier to create plots with darker backgrounds. This added the following fields to various plot objects.
TSPlot: TitleFontColor, TitleFontColorUse
TSSubplot: BackgroundColor2, AxisColor, GridLineColor, LegendColor, BackgroundColor2Use - Transient Stability: Modified plots so that you may specify whether fonts appear in bold. This added the following fields to various plot objects.
TSPlotVertAxisGroups: TitleFontBold
TSPlot: TitleFontBold
TSSubPlot: AxisTitleFontBold, TitleFontBold, FooterFontBold - Case Information Displays: Fixed out of range error that could result when saving Model Filters to an auxiliary file using the local menu option to Save As Auxiliary File on the Model Filter case information display.
- Oneline Diagrams: Right clicking on an unlinked bus display object could result in an access violation. This has been fixed.
Bug Fixes
December 1, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added a new script commands
CTGCloneMany(filter, "Prefix", "Suffix", SetSelected);
CTGCloneOne("ctgname", "newctgname", "Prefix", "Suffix", SetSelected);
See the Auxiliary File Format documentation for more information. - Case Information Displays: Limit Groups now have a Memo field for user-specified memos.
- GIC: The Time Step Simulation has been modified to better support time-varying GIC calculations. This includes the ability to enter an delay on the start of the GIC waveform. Also, in the GIC with the time-varying waveform times before the start of the waveform now return zero GIC voltages; previously they returned the starting values (this shouldn't matter much since the starting point is usually all zeros anyways).
- Transient Stability: Added the ability to plot a generator's apparent impedance R and X on the machine MVABase.
- PV and QV Curve (PVQV) Tool: When saving cases as part of PV state archiving, do not store any PV, QV, or ATC results to the cases.
- Transient Stability: When closing and reopening a plot inside the PowerWorld User Interface, the default height of the plot was shrinking by several pixels each time. This has been fixed to maintain the previous size of the plot dialog.
- Transient Stability: Some transient stability result fields for plotting and reporting are calculated from other values. For example, the Bus V in kV is calculated from the Vpu value. These calculated fields could be used, but they were not working properly when used as the horizontal axis value on a plot. This has been fixed.
- Transient Stability: Fixed an issue with SCl2 and OEL2C models. With the time inverse functions: K[(Ipu/ITPF)^C -1], when the Ipu is negative that will lead to an undefined solution. When Ipu is negative it is treated as zero and the exponential function (Ipu/ITPF)^C will return 0 and basically the output of the inverse function is set to -K.
Bug Fixes
November 22, 2021
Bug Fixes
- Power Flow Solution: Fixed error that can occur in rare situations when solving the power flow on a case that contains breakers, not using Integrated Topology Processing, and a portion of the system is islanded.
November 19, 2021
Features and Improvements
- Case Information Displays: Added more column plotting options
- Simulator Automation Server (SimAuto): In SimAuto command GetSpecificFieldList, modified to return the Enterable information in array index 4
- Transient Stability: For the REPC_A and REPC_B model, added features on August 31, 2021 to handle bad user-input when a branch is NOT specified in the input parameters. When this occurs, then previously we always treated P, Q, and I inputs to the model as 0.0. This was changed to instead use the output of the generator. However, there was a bug when PUFlag<>0 meaning the inputs were assumed on the model MVABase and the inputs were the PUFlag was not being handle properly when the branch was not specified and values of generator output were not scaled by MVABase. This has been fixed.
Bug Fixes
November 18, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): New script command CTGComboSolveAll(DoDistributed, ClearAllResults). This will run the contingency combination analysis for all primary and secondary contingencies that are set to not be skipped. DoDistributed is optional parameter that is NO by default. Set DoDistributed to YES to use distributed computing for the combination analysis. ClearAllResults is optional parameter that is YES by default. If YES all existing results will be cleared even if a primary contingency is marked to be skipped. If NO only those primary contingencies that are marked to not be skipped will have their results cleared.
- Auxiliary Files (SCRIPT and DATA Sections): New script command CTGComboDeleteAllResults that will delete all results that are associated with combination analysis including violations, what occurred, combination summary results, and injection sensitivities.
- Case Information Displays: added column to the Export Object Fields to show whether a particular field is Enterable in PowerWorld. The field with either be
Yes : means the field can be edited
AUX/Paste: means the field can be edited via an AUX file or via copy/paste features on a case information display
Blank : means the field can not be edited
Yes/Always: This means a field that can even be edited when other fields can not be (such as when in Difference Mode). An example is the Selected Field or the Area and Zone Shown field for filtering - Case Information Displays: On the Display/Column options dialog for a case information display, modified to allow you to show whether the field is enterable or not by using the font color of the field.
- Contingency Analysis Tool: Distributed computing can now be used with Contingency Combination Analysis. Each distributed process will analyze 1 primary contingency and as many secondary/regular contingencies as specified by the Number of Contingencies to Process.
- Simulator Automation Server (SimAuto): In the SimAuto command GetFieldList(), added an additional entry in the output for each field which shows information about whether the field is "Enterable". The value will be blank if the field is not enterable, otherwise an appropriate string will appear indicating when it is enterable.
- Case Information Displays: When show the Area Tielines and adding fields to show the Zone information for the tieline, if the table contained a lot of Load tielines it could be very slow. This was because PowerWorld was returning a list of "ALL zones that belong to the Area of the load" or the "Area of the bus". This could be a long list and would be repeatedly calculated. This has been changed so that instead we return the "Zone of the Load" and the "Zone of the Bus" instead as this is more in keeping with what is done for AC branches which return the "Zone of the Near Bus" and the "Zone of the Far Bus"
- Contingency Analysis: The contingency solution option to "Dynamically add/remove slack buses as topology is changed (Allow Multiple Islands)" CANNOT be set to allow multiple islands if it has previously been set to not allow multiple islands. This will be enforced when the contingency specific solution options are applied.
- Contingency Analysis: Abort button on the contingency combination analysis dialog should function correctly now.
Bug Fixes
November 17, 2021
Features and Improvements
- Case Information Displays: Added fields to store switched shunt summary fields for buses, areas, zones, and substations. This includes the Mvar range and the Mvar percent of range.
- Case Information Displays: Enhanced the StringGrid Column Plot to provide more flexibility.
- Contingency Analysis Tool: On the CTGComboResults object, modified to make the following fields enterable which then pass the enter to the appropriate Contingency or ContingencyPrimary object: CTGPRI_Skip, CTG_Skip, CTGPRI_CustomInteger, CTGPRI_CustomFloat, CTGPRI_CustomString, CTG_CustomInteger, CTG_CustomFloat, CTG_CustomString
- Oneline Diagrams: Added a new oneline display object for a Background Triangle.
- Oneline Diagrams: Made the option when importing a KML File to add the Points as Ellipse, Squares or Triangles.
- Time Step Simulation: Added warning messages in the log when specifying to store PWBs to a directory that does not exist.
- Time Step Simulation: Added ability to do DeleteColumns from the right to the left column. This can be faster for some case information displays.
- Time Step Simulation: Added option in Time Step Simulation to initialize load values from the current power flow case.
- User Interface Dialogs: Clicking on the Modify Transformer Parameters button will now open the three winding transformer dialog if the transformer is part of a three winding equivalent.
- User Interface Dialogs: When plotting generator reactive capability curves there is now a footnote at the bottom if AVRAble or Use Capability Curve are false. There is also a note if what is drawn is a default curve and not one that has been explicitly defined.
- Auxiliary Files (SCRIPT and DATA Sections): For 3-winding transformers there was a misspelling in the variable name for
3WXFMagnetizingG and 3WXFMagnetizingG which were spelled
3WXFMagetizingG and 3WXFMagetizingG instead (notice missing n).
These misspelling were fixed in Version 22, but Version 22 will also read the old misspelled variable names. In Version 21 the misspelling was left, but patches of Version 21 after this date will also read the correct spelling so AUX files written in Version 22 can be read in Version 21. - Auxiliary Files (SCRIPT and DATA Sections): When loading an AUX file or editing a case information display the 3WXFormer fields for RegBusNumSec and RegBusNumTer, the setting of regulated bus number was not being processed correctly. This has been fixed.
- Contingency Analysis: The contingency solution option to "Dynamically add/remove slack buses as topology is changed (Allow Multiple Islands)" CANNOT be set to allow multiple islands if it has previously been set to not allow multiple islands. This will be enforced when the contingency specific solution options are applied.
- Distributed Computation: Fixed an issue with distributed transient stability where transferring large result files could cause distributed transient stability to crash or hang.
- QV Curve Tool: The QV solution option to "Dynamically add/remove slack buses as topology is changed (Allow Multiple Islands)" CANNOT be set to allow multiple islands if it has previously been set to not allow multiple islands. This will be enforced when the QV specific solution options are applied.
- Time Step Simulation: Fixed a bug that could sometimes occurring when inserting new time points.
- Transient Stability: modified the CHATGY model to not accept a DC Auxiliary Controller input. This model has the parameters for a CHAAUT as part of it so accepting a different Auxiliary Controller was not appropriate.
Bug Fixes
November 9, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added new Iteratively Found string CTG_FAIL_ITERATED_OVERLOAD that indicates that the contingency failed to solve at some point during the Iterated Linear Step (IL) then Full CTG method and using the option to iterate on failed contingencies. The Transfer Limit that is reported is the accumulated amount that is possible for which the contingency solves, but the monitored element is overloaded, as determined by a linear step calculation, at this transfer level. Using the iterated method attempts to get as close as possible (within specified tolerances) to the highest transfer amount at which the contingency will solve. This is very similar to a PV nose point.
- Transient Stability: Added "MW Nominal Tripped" field for tracking and plotting results for loads in transient stability. It will also be recorded for Areas and Zones as a field. This field tracks the Nominal MW Tripped during the entire simulation.
- Available Transfer Capability (ATC) Tool: Removed the change made in the 6/22/21 patch for the ATC (IL) then Full CTG solution method that set the new stepsize to (stepsize + stepsize/2) when the stepsize is negative and the monitored element is overloaded. This change does not work in all situations. This was instead fixed by improving the ATC (IL) then Full CTG solution process when iterating on a failed contingency to better handle negative stepsizes and stepsize changes needed to find a solution for the contingency and attempt to reduce the loading on the monitored element to its limit.
- Sensitivity Calculations: Update the algorithm to determine unnecessary interface element line open elements to also catch buses isolated by contingent interface elements. The isolated buses cause numerical problems in the sensitivity calculations. The algorithm fixes this by removing one of the contingent interface elements. This has no effect on the interface flow because the flow through the bus is still zero, but fixes the numerical problems.
Bug Fixes
November 8, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Modified so the following objects can return information about any SupplementalData that contains the object referred to by the Violation or Signal: ViolationCTG, LimitViol, TSLimitViolation, TSResultAnalysisSignal, TSResultAnalysisViolation, TSResultAnalysisModeMagAngle
- Case Information Displays: Modified so the following objects can return information about any SupplementalData that contains the object referred to by the Violation or Signal: ViolationCTG, LimitViol, TSLimitViolation, TSResultAnalysisSignal, TSResultAnalysisViolation, TSResultAnalysisModeMagAngle
- Case Information Displays: For switched shunts, Mvar only, added fields to show the range (Max - Min) and the percentage of range. Both of these values are based on the nominal Mvar fields. On the range, since a switched shunt is ultimately switchable, zero is always a valid entry. So if switchedshunt has a fixed value of 100 Mvar, its range would be 100 since it could be opened. On the percentage there are two options. The first is the percent in the range. This value is always >= 0. The second is the percent about zero. This value can be negative if the shunt allows for negative values. For example, with a switchedshunts with limits between -100 and 100 Mvar, if its nominal output is -50 Mvar, the first percent would be 25%, and the second would be -50%.
- Case Information Displays: For buses added fields to show the generator reactive power reserves up and down and also the range.
- Case Information Displays: For Areas, Zones, and Substations, added the generator reactive power range as a field.
- Transient Stability: Added new fields for Transient Nominal Tripped Load for Area, Zones and Injection Groups.
- Transient Stability: For the Transient Result Analyzer, modified the Statistics for the ResultAnalysisSignal to also include the Final Value in the time period being studied
- Transient Stability: Modified TSResultAnalysisSignal and TSResultAnalysisViolation to show the first 9 custom float values for the object of the Signal or Violation. This makes it easy to copy values to the underlying object like a bus, load, etc... to then use for some user purpose.
- Transient Stability: When writing out a DYD file, modified the writing of CMPLDW models to write a #1 instead of a #9 to avoid hitting the maximum number of channels enforced in PSLF.
- User Interface Dialogs: Added a tab showing the list of switched shunts in the area; this matches what has long been available for Zones and Substations.
- User Interface Dialogs: Added fields to Switched Shunt dialog to show the terminal per unit voltage and the nominal voltage.
- Contingency Analysis: If a new Custom Monitor was created after contingency analysis had already been run, the results for the Custom Monitor would not always show up if using the Solve Selected Contingency option. This has been fixed.
- General: In TransLineCalc, fixed the conductor database to have the proper number of significant digits for the various conductor parameters.
- Transient Stability: When tracking the Percent field of a transmission branch, the value in transient stability is always the percentage of the MVA Limit. Previously it was not clear that this was the case.
Bug Fixes
November 1, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added special processing for ISO-New England for reading an entire case as an AUX file (called by choosing File\Option Case or when using the OpenCase script command). Previously, special processing was occurring whenever any AUX file Branch DATA section was read, but this was removed in the May 10, 2021 patch because the old behavior was causing bugs in some new ISO-NE processes. Dating back to 2006, ISO-NE had expected the PowerWorld would automatically populate the BranchDeviceType field when reading an AUX file that has Branch objects with CustomString, CustomString:1, or CustomString:2 fields with entries of "line", "zbr", "breaker" etc. The patch for today has brought back that behavior but ONLY when loading an entire case as an AUX file and when the BranchDeviceType field for a particular branch was not populated anywhere else in the AUX file. This new patch brings back the old behavior desired by ISO-NE, but prevents the problem with general AUX files found in May 2021.
- Available Transfer Capability (ATC) Tool: Script commands have been added to access these features: InterfaceRemoveDuplicates; and InjectionGroupRemoveDuplicates. (See Case Information Display patch update below for an explanation)
- Case Information Displays: When working with data that has been collected from multiple organizations, it is possible to have duplicate interface and injection group definitions that have the same elements but different names. Previously this was difficult to detect. We have added a feature to detect and remove duplicate injection groups and interface definitions. This is implemented with the 'Remove Duplicates' button which can be found in the local (right-click) menu for both objects. The 'Remove Duplicates' feature applies to all injection groups or interfaces. Any duplicate definitions are deleted from the model. For comparison purposes, an injection group participation point is considered to be the same if it is for the same object, has the same AutoCalc value, initial value, and participation factor. An interface element is considered to be the same if it references the same object with the same monitored and weighting. The order of the participation points or interface elements does not matter for the duplicates check.
- Oneline Diagrams: Added two new discrete 21 color maps that are suppose to work well in color blind situations.
Added a 34 color discrete contour that is similar to what is used by ERCOT for their LMP map. - Oneline Diagrams: Added an object list for KML File Imports objects. Also now can read lines and points that are not in PowerWorld Format. Points will be drawn as an ellipse.
- File Formats: Fixed a bug that could under very rare circumstances cause Simulator to hang or fail when opening older supported text file formats. This was not a problem with AUX files.
Bug Fixes
October 27, 2021
Features and Improvements
- Oneline Diagrams: On the Format Dialog, Display/Size page the X and Y values for the selected objects are shown, and can be changed. The dialog also shows the range of the X an Y values for all the selected objects.
- Oneline Diagrams: Made a minor change to the Align Group Objects function. Previously when taking a vertical group of objects and doing a horizontal align it would set the horizontal position based on the average of their x locations. Now it sets their position based on the horizontal location of the top one in the group. The same is true when aligning horizontally, except it uses the left one in the group.
- Contingency Analysis: If Contingency X resulted in a partial solution (some islands are solved while others are not) and the very next Contingency X+1 did not do anything (for example it opened a branch that was already open in the reference case), then Contingency X+1 would also report as a "Solved=Partial" instead of the correct "Solved=YES". This has been fixed.
- File Formats: When loading a case saved using the Save Two Bus Equivalent option with Transient Stability that contained Supplemental Data containing objects that are not saved with the two bus equivalent, an access violation could result. This has been fixed.
- QV Curve Tool: Fixed access violation that could occur when running QV analysis and no buses are selected for analysis.
Bug Fixes
October 25, 2021
Features and Improvements
- Time Step Simulation: Added a few more fields for showing the TimeDomainOPF input field counts, including a total input field count.
- Transient Stability: Bug fix for Line Relay models DISTRELAY and DISTRELAYITR.
When using TransferType = DUTT/PUTT/POTT/DCB, the communication signal was not obtained correctly from the companion relay.
This was affecting both tripping and reclosing of transfer trip lines (i.e. RecloseWithFault=0).
Bug Fixes
October 22, 2021
Features and Improvements
- Contingency Analysis Tool: Added local menu option to the Primary Contingency case information display to Insert Special > Auto Insert Primary Contingencies.
- Time Step Simulation: Fixed bug with pasting data into the Time Step Simulation. The issue is the paste was ignored for if the data did not already exist for the particular time point.
- Transient Stability: Bug fix for Line Relay models DISTRELAY and DISTRELAYITR.
When using TransferType = DUTT/PUTT/POTT/DCB, the communication signal was not obtained correctly from the companion relay.
This was affecting both tripping and reclosing of transfer trip lines (i.e. RecloseWithFault=0)
Bug Fixes
October 21, 2021
Features and Improvements
- Contingency Analysis Tool: Fixed an issue in Contingency Analysis. When Storing Results into Hard Drive if the file location didn't exist it was setting internally the file directory to nothing and it was causing the results to be lost when finishing the analysis. Now it will prompt an error for the user to fix the file directory before continuing with the analysis.
- Transient Stability: Added new Transient Contingency Action for a Shunt object to change the "Vsig or Vref" on the dynamic model. This can be used to perform a step-test in transient stability on a model such as SVSMO3 which has a Vsign that is initialized as part of the model.
October 18, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added new Iteratively Found string "INIT_RESERVE_LIMIT" that indicates that a reserve limit has been hit in the initial part of the iterated process when all limiters are iterated on. Hitting a reserve limit here will cause the entire process to stop and it wasn't obvious from the results that this had occurred; this was being reported in the ATC log but not with the TransferLimiter records.
- Transient Stability: Added parameter check for min and max in PF1 and VAR1.
- User Interface Dialogs: Previously when clicking on the button to change transformer parameters, if the branch was a three winding transformer section, we would just display a message telling the user to go to the three winding transformer table and open the three winding record to modify the parameters. I changed it so that now when you open the branch dialog of a transformer that is part of a three winding transformer, and click the button to modify the transformer parameters, the three winding transformer dialog is automatically opened (as a Modal form) so the user can edit the three winding parameters. When they click OK, it goes back to the branch dialog and calls SetInfo to update the two winding transformer displayed with any changes that were made to it from the three winding dialog.
- Auxiliary Files (SCRIPT and DATA Sections): In Version 22 there is now an option to "Save As\Auxiliary File with Options" when right-clicking on a case information display. This gives you more features to choose to save related objects (InterfaceElements with the Interface objects for example). Because of this feature it was easier to save Gen object along with their bid curves and as a result we removed a prompt asking you what to do when saving a list of generators. This was working, but it had inadvertently been written to ALWAYS write extra data sections for the generator bid curves and capability curves when saving a gen table. This has been fixed so it will not store those unless choosing to features in "Auxiliary File with Options"
- Auxiliary Files (SCRIPT and DATA Sections): When storing Extra Data sections as part of saving an AUX file (for example InterfaceElements with Interface objects), modified so that the default is 6 decimal places for the sub objects. Previously it was only 3 which was sometimes not enough to maintain precision.
- Available Transfer Capability (ATC) Tool: The ATC Multiple Scenario Results table is populated with information from the limiter with the lowest Trans Lim value from all limiters that have been iterated on. If none have been iterated on then it is populated from the limiter with the lowest Trans Lim value. It was possible if a reserve limit was hit during the initial part of the iterated process when all limiters are iterated on that the limiter chosen was the first one in the list and not necessarily the one with the lowest Trans Lim if none of the limits had been marked as being iterated on. This has been fixed.
- Available Transfer Capability (ATC) Tool: When attempting to get a failed contingency solution to solve using SOLUTIONFAIL actions, remaining SOLUTIONFAIL actions would not be applied if the last action made no changes. This has been fixed.
- Transient Stability: Modified how numeric fields of the PlayInInfo and PlayInSignal object are shown in the GUI and written to an AUX file.
Now, no matter what is specified for the number of decimal places, we will write at least 4 significant digits to ensure the user doesn't accidently truncate the digits too much.
Bug Fixes
October 13, 2021
Features and Improvements
- Case Information Displays: Added columns to LoadModelGroup objects which show the LoadMW, LoadMvar, DistMW, DistMvar, DistMWMin, DistMWMax, LoadNetMW, and LoadNetMvar. These fields show the summation of these quantities across all the loads assigned to the LoadModelGroup.
- Transient Stability: Added new exciter model ESURRY (from DYR) and exac1m (from DYD). These are the same exciter model and will be named ESURRY in PowerWorld Simulator, but when written out to a DYD file as an exac1m.
- User Interface Dialogs: Modified so the General File Browsing form is not closed when someone opens a case using the form.
- Contingency Analysis: Injection group contingency actions for Change By or Set To that are Persistent could cause excessive POSTCHECK iterations to occur when no changes are being made. This has been fixed.
- File Formats: Modified how fault impedance is specified when loading a type of fault from an OTGD file
- Transient Stability: Fixed a how parameter checks on values exceeding the maximum value allowed for the parameter was handled when validating data in transient stability.
- User Interface Dialogs: Fixed a bug in the line length field where entering a value string that was not a properly formatted number would result in a weird value inserted in the field instead of resetting the field value back to the previous valid value, as it should have been.
- User Interface Dialogs: Also modified the File Browser so that the Advanced Filter and Advanced Sort features work even when opening the File Browser dialog before open a case of any kind. Previously nuisance access violations could occur.
Bug Fixes
October 6, 2021
Features and Improvements
- Contingency Analysis Tool: AutoInsert of Primary Contingencies was added to the CTG Combo Analysis tool.
- Transient Stability: Added option to transient stability load modelling "Trip Extra Mvars from initialization when individual load components are tripping". By default this is set true. When true, then the Extra Mvars (Bf1 and Bf2 in the distribution equivalent model) calculated to balance the load components for complex loads such as CMPLDW, CMLD, CLOD, and LoadComp will be tripped as individual load components trip during the simulation. If this is set false, then all Extra Mvars will remain in service even as load components trip.
- Auxiliary Files (SCRIPT and DATA Sections): An error message will now appear in the message log when loading a blank interface element from an auxiliary file.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug in new feature added on September 30, 2021 to "Modify Definition due to Isolated Elements on Selected Interfaces". When run repeatedly on the same case it was adding duplicate actions for opening the same generator. This has been fixed.
- File Formats: Fixed access violation that could occur when loading a PWB file that contained blank unlinked interface elements.
- User Interface Dialogs: Fixed bug on the interface definition portion of the Model Explorer. When choose a particular interface the subtabs for Load Open and Gen Open were not properly showing the list of actions.
- User Interface Dialogs: Added a option for saving unlinked interface elements to an auxiliary file when using Save As Auxiliary File with Options when saving to an auxiliary file from the Interface case information display.
Bug Fixes
October 1, 2021
Features and Improvements
- Contingency Analysis Tool: Added Convert regular contingencies into Primary contingencies. The new option is located under the Insert Special menu by the option: "Convert into Primary Contingencies..."
- Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug where changing the SVC type of an SVC to type 2 or appending an SVC of type 2 using the AppendCase script command in an AUX file would cause an access violation.
Bug Fixes
September 30, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Also added a new script command to do the same with the syntax
InterfaceModifyIsolatedElements("filtername");
The filtername is an optional input parameter and if not specified that this is done on all interfaces. The filtername uses the common syntax for specifying either SELECTED, AREAZONE, Filter Name, or Device Filter.
- User Interface Dialogs: Added a new right-click menu option on a list of Interface Definitions to "Modify Definition due to Isolated Elements on Selected Interfaces"
September 28, 2021
Bug Fixes
- Optimal Power Flow (OPF): fixed potential oscillation in the solution of the DC OPF solution when using a case with 1000s of contingency interfaces defined on a larger case.
September 27, 2021
Bug Fixes
- Case Information Displays: Fixed error with using Difference Flows with CustomFloats and CustomIntegers.
- File Formats: Fixed bug when saving version 33 or less RAW files that could add a blank line at the start of the load records.
September 21, 2021
Features and Improvements
- File Formats: Added FaultType for BusFault and LineFault when reading a Transient OTGD file.
- Transient Stability: Added support for the model WTGIBFFR_A. This model is a Paux controller which is initiated for under-frequency events and plays into the Paux input on various governor and exciter (electrical control) models. In particular it is intended to be played into the REEC_D model for wind turbine models. The model can also be read and written to the DYD format.
- File Formats: When reading an OTGD transient file for elements that happened at the same time but a parameter (for example in a branch opening then NEAR and FAR End at the same time) was different it was not adding the event correctly. This has been fixed.
Bug Fixes
September 17, 2021
Features and Improvements
- Contingency Analysis Tool: On the Contingency Analysis dialog under the Results tab, there are tables show summary information about Branches, Buses, Interface, BusPairs, etc indicating how many different contingencies cause a violation on the respective object. Add a new option on the right-click menu under the object-specific sub menu to "Delete Associated Violations". This will delete all the violations associated with that object.
- Transient Stability: Fixed a bug that when adding a new field in transient stability in a new version, when loading the results from hard drive into RAM was showing an empty column corresponding to that field in the TimePoint Results Table.
- Transient Stability: Fixed initialization error when using an REGC_B machine model in combination of a type 3 wind turbine model using a WTGTRQ_A (or WTTQA1) model.
- User Interface Dialogs: Fixed field translations on the Display Explorer.
Bug Fixes
September 16, 2021
Features and Improvements
- Transient Stability: Modified REEC_D model so that the Thld2 parameter acts to freeze the value of Ipcmd instead of the value of Ipmax as is done in REEC_A model.
- Transient Stability: Added the ability to read and write models ESST1C and ESST4C to a dyd file. The equivalent models in PowerWorld are ESST1C = ST1C and ESST4C = ST4C.
- Transient Stability: Added support for REPC_C plant controller model
- Transient Stability: There is a bug that resulted in an Access Violation if you try to right click the Signals table with no signals in the table in the Modal Analysis Form in Transient stability.
- Transient Stability: Removed harmless but confusing event reporting in transient stability for out-of-service DC transmission line dynamic models.
- User Interface Dialogs: Fixed inconsistencies when changing between per unit and percentage voltage changes when using the options to never report or always report voltage violations with contingency analysis.
Bug Fixes
September 10, 2021
Bug Fixes
- Optimal Power Flow (OPF): In very rare situations for Interface definitions that contain many BRANCHOPEN InterfaceElements that result in the complete isolation of parts of the power system the calculation of the interface flow could become inaccurate. This could mess up calculations such as an OPF solution which uses the Interface MW flow to calculate the OPF solution. Internally, a numerical summation of very large values is done and that calculation was incorrectly using single-precision floats (7 significant digits). A user encountered an example where the equivalent of the subtraction of (123456789 - 123456789) was not returning 0.0 but instead what appeared to be random 2 digit number. This has been fixed by using double-precision instead to maintain enough significant digits to prevent this bug.
- Transient Stability: Fixed the option on the Transient Stability dialog when processing multiple contingencies to choose whether to show results by a single contingency or multiple contingencies on the Results from RAM tabs.
September 8, 2021
Bug Fixes
- Oneline Diagrams: Left-clicking and dragging on top of a background line when in Run Mode should simply pan the oneline in the direction of the dragging. This worked for most background lines, but not if the background line had been created by loading from a Shapefile. This has been fixed.
September 7, 2021
Bug Fixes
- GIC: Fixed some errors with trying to get results for a transient stability run of the transformer GIC.
- Transient Stability: Fixed some errors in VHVDC1 implementation.
September 3, 2021
Features and Improvements
- Transient Stability: Adding new REPC_C plant controller model for testing
- File Formats: Changes made in August 20, 2021 patch for storing information read from an EPC file regarding VSC DC Line objects caused a bug with saving out a PWB after loading a RAW file for a case that includes a VSC DC Line. This has been fixed.
Bug Fixes
September 2, 2021
Bug Fixes
- Transient Stability: Fixed a bug where distributed results were not being saved to hard drive.
- Transient Stability: When creating an open transient contingency action for a branch, the One Phase Open option will no longer appear on the GUI dialog. This option has not been implemented and an action defined as this would act the same as an Open Both action.
August 31, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added new script command LineLoadingReplicatorCalculate with the syntax
LineLoadingReplicatorCalculate([Branch 1 2 1], [InjectionGroup ig1], Yes, 50.0, NO, DC);
LineLoadingReplicatorCalculate([Branch 1 2 1], [InjectionGroup ig1], Yes, 50.0, NO, DC, No, 0.5, 2);
The parameters are
1. Identifying string for the branch
2. Identifying string for the injection group
3. YES or NO for whether to only include AGC=YES devices
4. Number representing the desired MW flow on the Branch
5. YES or NO for whether to implement the changes after performing the calculation
6. DC, AC, or DCPS for the linear solution method to use to perform calculation
7. Optional, YES means to use the fields MWMax and MWMin for limits on load changes. NO means to use a multiples of the existing load for the minimum and maximum, with the multiplies as next 2 parameters
8. Optional, If parameter 7 is NO, then this is the multiple of the existing load to use a minimum value (should be less than 1.00)
9. Optional, If parameter 7 is NO, then this is the multiple of the existing load to use a maximum value (should be greater than 1.00)
- Auxiliary Files (SCRIPT and DATA Sections): Added new script command LineLoadingReplicatorImplement. This command has no parameters. The command will implement the control changes found by the LineLoadingReplicatorCalculate() command, so it is important to run that command before this.
- File Formats: Added ability to store values read from EPC file for a 2-terminal DC line for values not used in power flow solution:
Rectifier Gamma Min, Rectifier Gamma Max, Inverter Alpha Min, and Inverter Alpha Max. While these values are not used with the power flow solution, the value Inverter Alpha Min is used in the recently added CHVDC2 model. That value is not included in the DYD record for the CHVDC2 model, so we must carry it around with power flow data to properly read EPC/DYD file pairs.
- Oneline Diagrams: Fixed how substation display objects use Default Drawing Values to highlight voltage limits. If showing the "Min kV of Highest Nom kV" or "Min PU of Highest Nom kV" fields within a substation display object, the color of this text will be the Limit Highlight Color specified with the Default Drawing Values if at least one bus in the substation is outside its voltage limits. If there is dynamic formatting in effect the dynamic formatting color will be used instead. The Limit Highlighting Used field was being ignored, but it is now being used to determine if the Limit Highlight Color should be used. The default color for the substation text will be used when the Limit Highlight Color is not used and in the absence of any dynamic formatting.
- Power Flow Solution: Fixed bug that could prevent the DC converter equations from solving to a solution very close to the minimum firing angle at the rectifier. The solution may instead setting a transformer step 1 stepsize away a solution near the mimimum firing angle.
- Transient Stability: Cleaned up the network boundary equation for the converters of a VSCDCT VSCDCLine dynamic model.
- Transient Stability: Modified the bad input data treatment when the branch P, Q, or I measurement are needed for an REPC_A model but a branch is not specified. Previously we just assumed all flow measurements were 0.0, but this has been changed so that in this situation we use the output of the generator instead.
- Transient Stability: Fixed a bug with Result Analyzer that was giving the wrong data value in some data points if the results were loaded from Hard Drive. For example a field that is scaled by SBase.
Bug Fixes
August 27, 2021
Bug Fixes
- Transient Stability: Modifying how blocking is treated in the VHVDC1 voltage source converter DC line model. Also cleaned up the network interface equations for the VHVDC1 VSC DC Line dynamic model
- Transient Stability: Fixed a bug where plots from a Distributed TS run were not being generated correctly when other results were not being stored
August 25, 2021
Features and Improvements
- Case Information Displays: Updated description for the Int MW field for areas, zones, etc. to better reflect how it is calculated.
- Oneline Diagrams: Improved the handling of Case Information Memo oneline fields.
- Transient Stability: Added ability to load the VHVDC1U user-written model from a DYR file and load it into a VHVDC1 model in PowerWorld. This is a voltage-source converter DC line model (VSCDCLine)
- Auxiliary Files (SCRIPT and DATA Sections): When interpreting interface elements for loads using a single string meant to represent the label of the load, it was possible for it to mis-identify the load if the user was using a label for a load that was exactly the same as either a bus number or "name_kv" of a bus in the system and that bus had a load. This has been fixed.
Bug Fixes
August 24, 2021
Bug Fixes
- File Formats: Fixed access violation that was introduced in previous patch on 8/20/21 which would occur when loading a RAW file with a DC line record. Bug only existed in 8/20/21 patch.
August 20, 2021
Features and Improvements
- File Formats: Added ability to read "vs converter data" from EPC files and then parse the records to create 2-terminal VSC DC Line objects. Also added the ability write the "vs converter data", "dc bus data", "dc line data" to an EPC file.
- Oneline Diagrams: Added a new feature called a Spatial View which can be used for temporarily laying out a part of the system using geography if available. Intent is for this feature to work like a temporary Bus View, though you will also be able to save the spatial view as a stand-alone oneline after building it.
- Power Flow Solution: Added 2 new options to modify the algebraic equations used to model line-commutated DC converters. Both options are not recommended, but when reading an EPC file PowerWorld will set these 2 options to YES so that the DC converter solutions will match the equations used by PSLF.
Use Approximate DC Converter Power Factor Equations:
Sim_Solution_Options VariableName = UsePSLFConverterApproximatePowerFactor
Set to YES to use an approximate calculation (to match what PSLF does) for DC converter power factor of
cos(Phi) = 1/2*(cos(FiringAngle) + cos(FiringAngle + mu))
instead of the more accurate equation
tan(Phi) = (2*mu + sin(2*FiringAngle) - sin(2*(mu + FiringAngle)))
/(cos(2*FiringAngle) - cos(2*(mu + FiringAngle)))
Use PSLF treatment of Fixed Tap in DC Converters:
Sim_Solution_Options VariableName = UsePSLFConverterIncorrectFixedTap
This only impacts DC converter transformer equations.
NO - Uses the correct equation of TotalTap = VariableTap + FixedTap - 1
YES- Uses the incorrect equation of TotalTap = VariableTap*FixedTap (implemented by PSLF). - Transient Stability: Added ability to read from a DYD file VHVDC1 models for 2-terminal VSCDCLine records.
- Transient Stability: Bug fix for generating plots of fields only if they are stored in Hard Drive (storing to RAM is okay). Users might have observed that incorrect values were being plotting fields of certain devices. For example, plotting the "OEL Other 1" field for a Generator which does not actually have an OEL Active. The correct behavior is to not show any plot series on the generated plot, because the field itself does not exist for that generator. This issue is now fixed.
Bug Fixes
August 18, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: For the TransferLimiter object type, the variables for ATC_ExtraMonitor and ATC_ExtraMonitorSens can now be identified by the object identifier for the object they are monitoring instead of the location number. Example: ATCExtraMonitor:"Branch '1' '2' '1'".
- File Formats: Fixed a bug where when reading an EPC file with multiple Shunt sections, we would only process the shunts in the last section read, and the previous sections of shunts would be lost.
- Oneline Diagrams: After the file save is complete when using the ExportOneline script command, the oneline will now be returned to the options and view that were in place prior to issuing the command.
- Transient Stability: Any OEL connected to Exciter ESST4B now has the ability to automatically modify the VOEL output so that initial limit violation can be prevented when the "Modify Limits" option is chosen in Transient Stability options. This modification will only occur if an OEL can initialize to Activation Status = Idle.
- Transient Stability: When Qref=0 for OEL4C, internally the program sets Qref to current Qmax from the power flow records. This was already being done. However, for generators that have an internal step up transformer, Qmax needed to be transformed to the generator terminal-side. This modification has now been made.
- Transient Stability: Fixed the Exciters EXAC1, EXAC1A, EXAC2, EXAC8B and REXS to work properly when the Hard Limit is implemented with the OEL1 Over excitation model. Previously the EFd limits were calculated without taking into effect of the function Fex in the output of the Exciter.
Bug Fixes
August 16, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): For ATCWriteToText script command, messages will appear in the log if any invalid field variable names are specified.
- Available Transfer Capability (ATC) Tool: Added new option for handling branch and interface limit violations in the PV tool. There is now an option called "Stop in Base Case Only" that can be applied to either type of violation. When this is used, only base case limit violations can cause a scenario to be critical. Any limit violations that occur for contingency scenarios will be ignored.
- Auxiliary Files (SCRIPT and DATA Sections): When loading a Custom Monitor from an auxiliary file or pasting from Excel and the Object Name is not specified as blank and cannot be found, set the Enabled field to NO so this custom monitor is ignored. When the Object Name is blank this means that all objects of the specified type will be monitored. Do not want all objects monitored by default if the particular object cannot be found.
- Transient Stability: Fixed a bug when the loads do not have a distributed generation model but do have distributed generation load defined with the load and the total load was negative. It was causing some transient solution problems. Also a warning will be presented when the distribution generation do not have a transient model but have distributed generation with the load.
- Transient Stability: Fixed a bug with the Result Analyzer Time Window dialog. When setting the Maximum number of violations to store, if a number greater than a 100 was set with the dialog, the value was set to a 100. In the Result Analyzer time window table the maximum number of violation to store was working fine.
Bug Fixes
August 9, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added a new script command named RotateBusAngleInIsland. The first parameter is the identifying information for a bus between square brackets and the second parameter is a numeric value for a new angle. The script command will rotate all the angles in the island to which the bus belongs by the same shift such that the specified bus ends up with a bus angle specified by the second parameter.
RotateBusAnglesInIsland([BUS num], Value); - Case Information Displays: Added a right-click option on a case information display of buses to "Rotate Bus Angles in Island". You then choose what angle you would like at the bus you have chosen and then all angles in the island to which this bus belongs are rotated by the same angle to achieve the desired angle at the chosen bus.
- Case Information Displays: Added fields to branches in Neighbors\Parallel Branches with Flipped Terminals to indicate if there are parallel branches with flipped terminals. This could indicate a modeling error, particularly for transformers.
- Transient Stability: In VHVDC1 the Pacref is treated as equal to 0.0 when either converter is blocked. This modification also changes it so that Idcref is also treated as 0.0 when either converter is blocked. This only mattered when using the dPmax and dPmin values to enforce a rate limit on the change in Pacref.
- Transient Stability: Added the signals 'Iact', 'Ibias', 'Terr', 'IERRinv1' and 'IERRinv2' for the OEL2C model Other Fields.
- User Interface Dialogs: Added button to the Edit Mode Branch dialog to allow the easy flipping of the from and to buses.
- File Formats: Fixed an access violation that could occur when during saving/loading primary contingency records.
- File Formats: Fixed access violation that would occur when loading an EPC file which contained no Shunt record section.
- Transient Stability: More robust initialization for OEL2C.
- Transient Stability: When an OEL model was getting VFE from generators as an input it was not getting the VFE correctly.
- User Interface Dialogs: Fixed bug when entering the branch Length on the Branch Options dialog while in edit mode. The edit box was being updated with a conversion to the selected miles or km unit while typing a new value making it impossible to enter the desired value.
Bug Fixes
July 30, 2021
Features and Improvements
- File Formats: Adding features to load RAW Version 35 files
July 29, 2021
Bug Fixes
- GIC: On GIC, Time Varying Electric Fields added error message is someone tries to load an upsupported file type. Previously this was causing an exception error.
- Transient Stability: Fixed a bug in where the Result Analyzer wasn't working when needed to load results from Hard Drive. Now it loads results from hard drive and also works to load some results from RAM and Hard Drive at the same time.
- User Interface Dialogs: Fixed a bug with the Generator Display dialog in Edit Mode when modifying the Voltage Tolerance it was setting the Voltage Setpoint to the Voltage Tolerance when you close the dialog or hit the Save button.
July 23, 2021
Features and Improvements
- File Formats: Fixed a bug with the MBL in the WECC switch file that wasn't creating the transient contingency. Now it will create the MBL transient contingency.
July 22, 2021
Features and Improvements
- General: On the Tools, Connections, Determine Shortest Path Between
1) added a tab that shows the lines that are in the path
2) corrected the order in which the buses are shown to start at the start bus and go to the end bus, 3) on the list displays for the buses, substations, areas and zones added a local menu entry to get access to this form. Because the Buses list display already had local menu entry to another form for showing the shortest path it now has two options with the original (older) approach labeled as old. A difference with the older approach is it did include DC lines show some folks might prefer that. This old form also now shows lines. - Transient Stability: Changed the transient stability so when a generator is closed by default its MW setpoint is not set to zero. However the generator is taken off of AGC control.
- Transient Stability: Changes associated with closing a generator in transient stability. Now they work correctly when closed at off-nominal speed. Also, AGC control is disabled when a generator is reclosed.
- Transient Stability: Cleaning up captions for transient events when specifying to close generators.
- Transient Stability: Fixed a bug where TS plots in a Distributed run were showing up blank if other results were not saved.
- Transient Stability: Fixed a bug with the OEL2C that was creating an initialization problem for the exciters derivatives because it was setting the OEL output to the incorrect initial value.
- User Interface Dialogs: Fixed errors on the Direction dialog
Bug Fixes
July 16, 2021
Features and Improvements
- Oneline Diagrams: When auto inserting buses or substations on a oneline diagram based on geographic coordinates stored with data records and the coordinates are not valid, messages will now appear in the log indicating that objects could not be added to the oneline.
- Transient Stability: Changed the defaults for the TTSGenOther_AGCControlModel_BASE to all zeros to emphasize by default they are automatically set.
- Transient Stability: Improved network convergence when CHVDC2 model uses the commutation failure features.
- Transient Stability: Added ability to feed in the auxiliary current signal into the CHVDC2 model
July 15, 2021
Features and Improvements
- User Interface Dialogs: On BusesShortestPath added showing the lines. This can then be used with GDV displays.
- User Interface Dialogs: Removed the Close button on the Keyboard Shortcuts dialog because it didn't do anything. The X to close the dialog does everything that needs to be handled before the dialog is closed.
- General: Improved performance when deleting GICXFormers.
- General: Fixed an issue where downgrading from a later patch release to an earlier patch release would break the Simulator installation causing the main executable to not be replaced by the earlier version executable.
- Transient Stability: Temporary disabling the Result Analyzer when using the State Manual Control tool button pressing of One Time Step or Until a Specific Time. You can do it after the simulation stops is just that the default is to check for the Analyze Time Window option and if it is checked then it will do it right after the simulation stops and sometimes we do not have enough points and create access violations and other issues.
- User Interface Dialogs: New features from July 7 for directly specifying a Custom Detail were not working properly and caused the CustomDetail dialog to appear when opening the oneline display options dialog. This has been fixed.
Bug Fixes
July 9, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added LoadAXDFromAXD("filename", CreateIfNotFound) script command that will allow a display auxiliary file (AXD) to be loaded via this script command that is part of another display auxiliary file (AXD).
- Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug that when the the script command was using a space in the string for a file type it was causing an error in the script command. Now if the user put a space in the file type of the script command it will not cause an error for the script.
- Available Transfer Capability (ATC) Tool: When doing an ATC calculation, a contingency that completely isolates either the buyer or seller will be ignored by the ATC calculation.
Bug Fixes
July 8, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): FixFlowArrowLineEnds and FixFlowArrowPosition script commands now have both input parameters as optional. When the Oneline name is not specified the script commands will be applied to the oneline for which the AXD file was applied. When the LayerName is not specified any flow arrow objects in any layer will be modified.
- Transient Stability: For stability added an offset field to the Area AGC to that all the area agc dispatch does not occur at the same time. Ideally this field is a random value that is between -0.5 and +0.5 of the update time.
- Transient Stability: Fixed a bug that when loading Advanced Options in Transient Stability plots, if the chart have more than one subplot it was causing an error. That error was fixed and the advanced options are loaded for the entire chart.
Bug Fixes
July 7, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: Added script command ATCWriteScenarioLog("filename", AppendFile, filter) that will write the detailed log information for ATC Multiple Scenarios.
- General: When a case has been modified a prompt to save the case will appear by default if opening another case, open a new blank case, or closing Simulator. If this happens while the contingency dialog is open and the system state is not in the contingency reference state, another prompt appears asking if the contingency state should be saved. There is now an option to Cancel so that the original action that led to the prompt will be abandoned and allow the case to be saved as the modified base case and not the contingency state.
- General: Added an option on the Simulator Options Environment page to "Prompt for saving modified case." This is checked by default. This is only stored in the registry and does not have auxiliary file support. When not checked the prompt for saving a modified case when opening a new case, opening a new blank case, or closing Simulator will not appear.
- User Interface Dialogs: Added ability to access saved custom Display Detail levels both through the Options ribbon tab and through the local menu on onelines.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed an "ID collision" error that could occur when trying to move a three-winding transformer to different buses or change the ID.
Bug Fixes
July 1, 2021
Features and Improvements
- Optimal Power Flow (OPF): Previously it was possible to attempt to solve the OPF/SCOPF with the Island-based AGC enabled. This should not have been allowed since it is using two different algorithms to dispatch the same generation. The code has been modified to present an error message 'Error: cannot solve OPF with Island-based AGC enabled.' when an OPF/SCOPF solution is attempted with Island-based AGC enabled.
- Security Constrained OPF (SCOPF) Tool: Previously it was possible to attempt to solve the OPF/SCOPF with the Island-based AGC enabled. This should not have been allowed since it is using two different algorithms to dispatch the same generation. The code has been modified to present an error message 'Error: cannot solve OPF with Island-based AGC enabled.' when an OPF/SCOPF solution is attempted with Island-based AGC enabled.
June 30, 2021
Features and Improvements
- Power Flow Solution: Added Message Log warning messages when a VSC DC Line is not properly configured to alert the user that the VSC DC Line is being ignored. As an example, if both converters are configured for MW control and error message will be generated that says "DCMode at From and To Converter are both the same. One side must be set to Power and the other to Voltage for the VSCDC Line to operate."
- Security Constrained OPF (SCOPF) Tool: set hints for the SCOPF form options, and added longer descriptions for them
- Contingency Analysis: Fixed bug properly displaying contingency injection sensitivity results in the Contingency Violations Display (LimitViol object type).
- Distributed Computation: Fixed distributed computation computer verification so that when no machines are defined, verification no longer causes Simulator to freeze.
- Optimal Power Flow (OPF): In some cases MWMarginalCostValues was not being saved as subdata when saving an AUX file
- Power Flow Solution: If a generator had a negative MW output and it was using Boundary Power Factor control to set the Mvar limits, the Mvar limits would end up switched with the minimum being positive and the maximum being negative. This has been fixed.
Bug Fixes
June 28, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: When storing ATC Extra Monitor flow values in the base case for use when estimating extra monitor flows at various transfer levels when using the iterated ATC methods, an extra flow value will now be included when contingencies are being iterated on at the base case transfer level at which the contingency last solved.
- Power Flow Solution: Added option to "Use Loss Factor For DC Line tielines". This will use the two-terminal DC line aLoss term to assign the metered point a fraction of the way along a two-terminal DC line. This term was always maintained previously but not used in the solution. This feature is supported in EPC files but not RAW files. PowerWorld Simulator now has a global option regarding whether to use this Loss Factor. When not using the Loss Factor (aLoss) we will default back to the MeteredEnd specification instead.
June 25, 2021
Features and Improvements
- Case Information Displays: Exposed multi-section line ID field in the branch table under the Multi-Section Line folder with the name MS Line ID.
- GIC: Modified so the GIC Analysis Form, Field/Voltage Input the Non-Uniform Input Field (usually a b3d) field is enterable with the result saved.
- Transient Stability: When reporting total load for the entire case in transient stability when load models include a distribution equivalent, the totals were not correct. They were correct for individual loads, areas, zones, substations, etc... but not for the entire case. This has been fixed.
- Transient Stability: Fixed an access violation when Saving Data from the Show/Save Selected Plot Data option in the Plot Designer. The error was happening when the plot included a PlayIn Signal. It was preventing the data from been saved. This error was fixed.
Bug Fixes
June 22, 2021
Features and Improvements
- Contingency Analysis Tool: Added code to keep unlinked contingency elements when reading OTG contingency files. Previously unlinked contingency actions were discarded.
- Oneline Diagrams: The Text Object dialog now has a format button to give direct access to the format dialog. This matches what has long been done with the line dialog.
- Available Transfer Capability (ATC) Tool: In ATC when using the (IL) then Full CTG solution method, corrected how a negative stepsize is handled when iterating on a failed contingency and the limiting element is overloaded at a step when the contingency does solve. When iterating on a failed contingency the stepsize is reduced by half if trying to find a transfer where the limiting element is not overloaded. This is incorrect if the stepsize is negative because the stepsize needs to become more negative to reduce the loading on the limiting element. The new stepsize is now (stepsize + stepsize/2) to make it more negative.
- Available Transfer Capability (ATC) Tool: Fixed a couple of inconsistencies with the ATC solution when using the (IL) then Full CTG Solution.
(1) When iterating on individual limiters with a contingency implemented, use the OTDF cutoff threshold instead of the PTDF cutoff threshold.
(2) When iterating on individual limiters with a contingency and an infinite transfer level is reached during the step where the limiter is iterated on by linearly modeling the contingency, no longer continue to the step where the contingency is actually implemented. The result will report Iteratively Found as YES_INFINITE. - Contingency Analysis: Fixed infinite loop that might result when using Best Fit actions for contingencies and remedial actions.
- Transient Stability: Fixed a divided by zero in HYG3 when (fRelec = 0) and (fRGate = 0).
- Transient Stability: There was an access violation bug when no results are saved into RAM or Hard Drive but saving plots as a file. The problem is fixed.
Bug Fixes
June 17, 2021
Bug Fixes
- Difference Case Tool: Fixed an access violation that would occur when saving present case topological differences over an entire model when some of those changes include new or changed three winding transformer star buses.
- File Formats: When loading a FACTS device from a PTI RAW file which was translated to a switched shunt SVC with svsmo3 there was a divide by zero error occurring. This has been fixed.
June 15, 2021
Features and Improvements
- Oneline Diagrams: Enhanced ability for finding objects on a oneline diagram
- Case Information Displays: Fixed a bug with Limit Monitors when creating a limit monitor the user puts a bus pair limit greater than A, B, C pr D. It was creating an access violation. This is now fixed.
Bug Fixes
June 11, 2021
Bug Fixes
- Oneline Diagrams: Added error message to InsertConnectedBusesAction when trying to insert buses connected to a display bus based on it being linked to the specified data Bus object if no display objects can be found. This is not considered a fatal error.
June 10, 2021
Bug Fixes
- Oneline Diagrams: In the AutoInsertBorders_Options object more than one border file can be specified to be applied at one time. This would not work if the specified borders included spaces before or after the comma delimiter. This has been fixed.
- Oneline Diagrams: Fixed access violation that could occur when auto inserting interfaces on a oneline diagram.
- Transient Stability: Fixed an access violation that happens when the transient simulation is aborted because of limit monitors and there are not enough points to do the result analyzer modal analysis. Now it will not have the access violation and the modal analysis will not be done.
- Transient Stability: When auto-inserting transient contingencies the multiple contingency grid was not refreshing and showing the new inserted contingencies. You needed to get out of the multiple contingency option and return back in order for the grid to refresh. That was fixed and now will refresh after auto-inserting contingencies.
June 9, 2021
Features and Improvements
- Case Information Displays: Fixed bug that was making the Bus Fields LoadNetMW and NetMW conflict with one another resulting in the NetMW field (showing the net injection at the bus) to not work properly. (Same fix for LoadNetMvar and NetMvar).
- Optimal Power Flow (OPF): Fixed OPF initialization problem.
- Security Constrained OPF (SCOPF) Tool: Included two additional SCOPF options when saving the options to an AUX file: "Set Solution as Contingency Analysis Reference Case" and "Basecase Solution Method"
- User Interface Dialogs: The Close and Help buttons on the SCOPF dialog would move to the right when increasing the size of the dialog. This has been fixed.
Bug Fixes
June 7, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added AXD file support of GeoDataViewSummaryObjects and SummaryLineObjects.
- Transient Stability: Added code for Critical Clearing time to work with result window analyzer and eliminated the messages from appearing when running the analysis in other than the result analyzer gui.
Bug Fixes
June 4, 2021
Features and Improvements
- Power Flow Solution: Continued improvements with handling switched shunt ranges voltage setpoints that may conflict with generator setpoints.
- Oneline Diagrams: When showing the oneline option to show out-of-service elements as dashed lines, the symbols for a transformer and series cap/reactors were not showing as dashed. The line segments up until the symbol were dashed, but not the symbol. This has been fixed so that the symbol also appears as dashed.
- Security Constrained OPF (SCOPF) Tool: Included two additional SCOPF options when saving the options to an AUX file: "Set Solution as Contingency Analysis Reference Case" and "Basecase Solution Method"
- Transient Stability: Added exciter ESST1A_GE to be able to set a Hard Limit with the over excitation OEL1.
- Transient Stability: UEL2C now allows parameter KUI = 0
- User Interface Dialogs: Fixed a bug with the Switched Shunts dialog that when the shunt is an svsmo3 was showing the current pu values multiplied by the Sbase for the Continuous Range and the Switching Range. Now it will show the values in pu value of the current. A better caption was inserted for making explicitly that the Continuous Range and the Switching Range is in pu of the current.
Bug Fixes
June 2, 2021
Bug Fixes
- File Formats: ZBR Threshold value used when determining regulated buses for generators, switched shunts, and transformers was not being saved to PWB files. This has been fixed.
- General: Added more error checking when copying and pasting so that errors don't result in access violations.
- Oneline Diagrams: When showing the oneline option to show out-of-service elements as dashed lines, the symbols for a transformer and series cap/reactors were not showing as dashed. The line segments up until the symbol were dashed, but not the symbol. This has been fixed so that the symbol also appears as dashed.
- Power Flow Solution: ZBR Threshold value used when determining regulated buses for generators, switched shunts, and transformers was not being saved to PWB files. This has been fixed.
- User Interface Dialogs: When using an SVC type svsmo3 the Switching parameters are in Amps. We were using them in Amps in our code but the dialog was displaying the Switching parameters as Mvar. Now it shows Amps in the dialog for the switching parameter.
June 1, 2021
Features and Improvements
- Transient Stability: modified treatment of D term for the new MOTORC to be the exponent for mechanical power.
- Transient Stability: Added ability to read/write the ESAC8C model from a DYD record.
- Case Information Displays: Fixed fields displaying improperly when in base case or difference display mode.
- Case Information Displays: Fixed access violation that could occur when loading auxiliary file with DataGrid section that contains an empty ColumnContourInfo subdata section.
- Contingency Analysis: Bug fix for access violation during saving a case with contingency results and then deleting a transmission line. This would happen if one of the terminal buses was referenced in the Contingency Elements as a Bus open or close.
- Distributed Computation: Fixed an issue where distributed transient stability didn't return result analysis violations. This is now fixed.
Bug Fixes
May 27, 2021
Features and Improvements
- Transient Stability: Added a new load model named MOTORC which is a combination of the INDMOT1P with the same contactor, under-voltage, and thermal relays added as used in LD1PAC.
- Available Transfer Capability (ATC) Tool: Transfer Limiter case information displays for specific types of limiters were not displaying the correct column headers when viewing Normal headers. This has been fixed.
- Contingency Analysis: Fixed access violation that would occur when saving primary contingencies without any results. The code was attempting to access the results without first initializing them.
Bug Fixes
May 26, 2021
Features and Improvements
- Contingency Analysis Tool: Modified the Best Fit Open contingency and RAS actions for Interfaces and Injection Groups. The algorithm attempts to find the smallest number of devices that can meet the desired amount. The more devices there are to consider the more time it takes to determine all of the possible combinations. If there are more than 20 devices, the devices will be sorted from high to low impact and examined in blocks of 20. If the entire 20 devices are needed to meet the desired amount all will be opened and then next block of 20 devices will be used to meet the remaining amount. This process continues until it is not required that a set of 20 devices are all required to meet the remaining amount. This block will use the combination algorithm to fine tune which devices are opened.
- Transient Stability: Internal modifications to the LD1PAC model to split up the features of the under voltage, contactor, and thermal relays into pieces so that these can be applied to other load models
- Transient Stability: modified SVSMO3 so that values of Kdbd < 1.0 are treated as Kdbd = 1.0
May 25, 2021
Features and Improvements
- Available Transfer Capability (ATC) Tool: With iterated ATC methods added two new Iteratively Found strings: YES_INFINITE and FULL_INFINITE. These indicate that the PTDF/OTDF have become too small in the process of iterating on an individual limiter, and the transfer limit is treated as infinite. This had previously been indicated by the Trans Lim value being set to a very large number, and now these new strings give another clearer indication of this. Additionally, the highlight color for these types of limiters are lighter versions of yellow and blue used to indicate YES and FULL limiters, respectively.
- Contingency Analysis Tool: Added script command CTGVerifyIteratedLinearActions that takes a single parameter, filename, for an input. This action will save a file that identifies which fields and conditional actions (remedial actions) are valid for use with the iterated linear analysis method for contingency and ATC analysis.
- Transient Stability: For some exciters added checking when E1=E2 and SE1 <> SE2 <> 0.
- Distributed Computation: When running distributed contingency analysis the Selected field for Contingency objects was being set to NO after the run. This has been fixed.
Bug Fixes
May 24, 2021
Features and Improvements
- GIC: Updated GIC code to better handle intermediate buses of multi-section lines. If the intermediate bus does not have any latitude/longitude specified then we will estimate the location using branch resistance values.
- User Interface Dialogs: Updating the multi-section line dialog. There is now a regular listing of the buses in the object.
- Contingency Analysis: When saving a PWB file and the contingency analysis dialog was open, the options as set on the dialog were not always being saved to the PWB file. This has been fixed.
- File Formats: When reading an EPC file and SVCs are allowed to control fixed shunts the linking to the fixed shunts was not being done correctly. This has been fixed.
- Oneline Diagrams: Fixed a bug where the Snap To Grid setting was continually being reset to True
- Power Flow Solution: When multiple lines that are not in series are closed and they have common bus terminals, angle smoothing does not work correctly. When this situation is encountered voltage estimates will be done instead on the buses that are involved in the line closures
Bug Fixes
May 19, 2021
Features and Improvements
- User Interface Dialogs: Updated the Multi-Section Lines dialog to include geography and GIC field support. Also added buttons on the Branch dialog to provide access to the Multi-Section Line dialog. Also also added fields to a branch to show if there are in-service or bypassed series capacitors on lines.
- File Formats: Corrected some fields written for SVD devices in the EPC format export.
- Oneline Diagrams: Fixed a bug where some display elements were not properly linking to their intended anchors when loading a PWD file
- Transient Stability: Fixed error in how the short-term Rating Curve is applied to the SVSMO3 model. This was not allowing the SVSMO3 to supply a current a multiple of Ishrt higher for a short period of time when configured to do so.
Bug Fixes
May 18, 2021
Features and Improvements
- Transient Stability: Modified how network boundary equation solution is handled when bypassing a DC line using the CHVDC2 model. It now ensures that an extra solution occurs and bus frequency calculation is updated to prevent strange bus frequency calculation spikes when bypassing and unbypassing.
May 14, 2021
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): SaveData script command will now produce an warning message if an empty fieldlist is specified.
- Available Transfer Capability (ATC) Tool: Fixed access violation bug when deleting transfer directions from multiple direction ATC analysis. This only happened after ATC analysis had been run (i.e., transfer limiter results were present).
May 13, 2021
Features and Improvements
- Case Information Displays: Added new summary information for the summation of Load Dist MW Max, Load Dist MW Min, Load Net MW, and Load New Mvar for the following aggregations: Bus, Area, Zone, Substation, Owner, InjectionGroup. Previously you could only get information about the Min/Max and Net values for loads by looking at individual load records or by creating your own calculated field.
- Distributed Computation: Fixed an issue in distributed contingency analysis where contingency violation injection sensitivities may be dropped when the controlling Simulator program is running on a computer under high load.
- Distributed Computation: Added the ability to gather worst overload data over all contingencies for all branches when running distributed contingency analysis. Previously this data was only available through non-distributed contingency analysis.
- File Formats: Bug fix for RAW file reading. Angle value was not being set correctly for node data read from a "SUBSTATION NODE DATA" section.
- Transient Stability: Modification to help with numerical integration of the INDMOT1P and INDMOT1P_PTR load models
Bug Fixes
May 11, 2021
Features and Improvements
- Case Information Displays: When creating a new Case Comment through script or aux file, a blank Time can be specified. Time is used as a key field so the current time will be increased in second increments until a unique time is found when loading multiple comments at the same time.
- Transient Stability: In PowerWorld parameters T1, T2, T3 and T4 are in seconds in DISTRELAY and DISTRELAYITR but in DYD files those parameters are in cycles in DISTREL. These paraemters are now properly converted accordingly when reading and writing those parameters from the DYD format
- Transient Stability: Exciters DC4B, ESDC4B and DC4C modification of Max limits at initialization.
Bug Fixes
May 10, 2021
Features and Improvements
- Transient Stability: Modified so that if the State Pitch (output) of WTGPT_B is stuck at a non-windup limit, then if the PitchControl state has a derivative pushing the output further against its limit the PitchControl state derivative will also be set to 0.
- Transient Stability: Modified so that if the State Pitch (output) of WTGPT_B is stuck at a non-windup limit, then if the PitchComp state has a derivative pushing the output further against its limit the PitchComp state derivative will also be set to 0
- Transient Stability: Modified the REEC_D electrical control model so that when it goes into a blocking mode it instantaneously forces the currents at the network boundary equations of the generator to go to zero.
- Transient Stability: Added a way to store DYD extra records in the pwb. Records like for a vscdc line or a dcmt model can be read. The strings can be saved with the pwb case and the user can see the string in a case info table and can delete them if desired. Then you can save the dyd file and those extra records will be also in the file.
- Transient Stability: On the Modal Analysis Form there is now an option to Always Reload Signals from Source. If checked then the modal analysis signals are always reloaded from the source, as opposed to using the signals already in Modal Analysis. This option is most useful when the source is changing and the user would like Modal Analysis to always use the new source value. An example is when the source is the TS plots. This option is useful when the user is changing the TS and rerunning, and then looking at how the modal analysis results have changed.
- File Formats: Removed old process that would update BranchDeviceType for a branch based on entries in CustomString:0, CustomString:1, or CustomString:2 after loading any aux file with branch data or using a SetData command on branch data. (This dated from 2006 and should have been removed years ago)
- File Formats: Fixed failed power flow solutions that might occur when opening an EPC file while in edit mode.
- GIC: Bug fix for reading PSLF *.GMD supplemental data file for (i) rdcsw/common parameter of 2 winding transformer, and (ii) kfactor for 3 winding transformer.
Bug Fixes
May 3, 2021
Features and Improvements
- Transient Stability: Added the ability to read and write ESST5C model to a dyd file.
- Transient Stability: Added the ability to read and write ESST6C model to a dyd file.
- Transient Stability: Added stator frequency dependence on the CIM5_PTR model
- Auxiliary Files (SCRIPT and DATA Sections): In the SendToExcel script command the ClearExisting parameter was not being read correctly if enclosed in double quotes. This has been fixed.
- Contingency Analysis: When using transient stability models with power flow contingency analysis no changes should be attempted if the device or the device's bus is disconnected. Not checking the bus connection status could cause excessive POSTCHECK loops. This has been fixed.
Bug Fixes
April 30, 2021
Features and Improvements
- General: Made modification to load ID assignment when merging buses. Previously the next unused ID was used even when the default was available. Now the default ID will be used if there is not already a load at the bus using the ID. This is consistent with how other objects like generators work.
- Transient Stability: Added a new dynamic phasor model of a single-phase induction motor model named INDMOT1P
https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20INDMOT1P.htm - Transient Stability: Added a new motor model named INDMOT1P_PTR which is a simplified version of INDMOT1P, but includes the concept of progressive tripping and reconnecting
https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20INDMOT1P_PTR.htm - Transient Stability: Added a new motor model named CIM5_PTR which is the same as CIM5, but includes the concept of progressive tripping and reconnecting
https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20CIM5_PTR.htm - File Formats: Fixed a bug where Simulator will save a modified case to an incorrect location when opening a different case. Simulator would save the case to the same folder containing the newly opened case instead of the folder where the case was originally stored.
- Transient Stability: Fixing reading, writing and setting MWCap from a dyd file for governors PIDGOV and WT4T.
Bug Fixes
April 29, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added column contour to the AUX format as a SUBDATA section on the DataGrid (string grid customization) object.
- Available Transfer Capability (ATC) Tool: When using iterated ATC methods the ramping is done relative to load and generator outputs in the base case so that generators will hit and back off limits consistently if transfer stepsizes change sign. When using injection groups as the source and sink it was possible that the ramping was being done relative to the total transfer already achieved rather than this base starting point. This could result in oscillatory behavior. This has been fixed.
- Transient Stability: Fixed a bug in which the reading a dyd file a certain dc branch wasn't loading the dynamic ecpdc model. Now this is corrected and the epcdc model is read into transient stability.
- Transient Stability: Fixed a bug with writing cmpldwg DGMBase parameter. When saving into dyd file and the load object DGMBase value is zero it was writing the load object DGMBase value as zero and not the transient model value.
- Transient Stability: Corrected UEL model MNLEX2. The other fields: Activation Status and PQSig values were being output incorrectly.
Bug Fixes
April 27, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added support for a Selected field with QVCurve object type. Added support for the Bus Selected field for the bus associated with the QV scenario.
- QV Curves: Added script command QVWriteCurves("filename", IncludeQuantitiesToTrack, filter, Append) that will save a comma-separated text file with the QV curve points. Set IncludeQuantitiesToTrack to YES to also include any Quantities to Track along with the curve QV curve points. Filter is applied to the QVCurve object type. Set Append to YES to append results to an existing file or NO to overwrite an existing file.
- Auxiliary Files (SCRIPT and DATA Sections): The special keywords for @DATE and @TIME used with script commands were providing the opposite replacement. @DATE was giving the time and @TIME was giving the date. This has been fixed.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed access violation that would occur with SendToExcel script command if Header_List was not defined.
Bug Fixes
April 23, 2021
Features and Improvements
- QV Curves: When running QV analysis, saving Quantities to Track while the analysis is running is now optional. This can slow down the processing. There is now a button on the Output tab of the QV dialog that allows saving Quantities to Track after the run is complete. There are also options on the local menu of the Results > Listing case information display that allow saving QV curve points with and without quantities to track.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed writing out auxiliary files so that they honor non-US regional Windows settings (i.e. using commas or periods as the decimal separator).
Bug Fixes
April 20, 2021
Features and Improvements
- File Formats: RAW file reading for version 34 is now more lenient and allows the use of whitespace as a field delimiter.
- Transient Stability: Vfe is available for ESAC5A Exciter model.
- Contingency Analysis: When loading a PTI CON file with contingency elements specified with WND for opening or closing a single winding of a three-winding transformer, the elements read after this entry could end up being incorrectly specified. This has been fixed.
- Power Flow Solution: Fixed an access violation that would occur when loading a case with more than 8 buses in islands without generation attached to DC lines.
- QV Curve Tool: When rerunning QV analysis delete all quantities to track even if not rerunning particular scenarios so that the values in the file will have consistent headers.
- QV Curve Tool: QV results for Quantities to Track were not being stored in PWB files. This has been fixed.
- QV Curve Tool: When rerunning QV analysis existing results should be overwritten when rerunning a scenario instead of creating multiple results for the same scenario. This has been fixed.
- Transient Stability: Changed default parameters for VHVDC1 so that Iqmin2 and Iqmin3 are both negative values (as these should almost always be negative!).
- Transient Stability: Fixed divide by zero when simulating VHVDC1 when Rdc = 0 in the power flow model and also L = 0 in the dynamic model.
Bug Fixes
April 13, 2021
Features and Improvements
- QV Curves: On the QV dialog fixed the location of the browse button that allows selection of an output file.
- Transient Stability: Made initialization of SCL2C more robust.
Bug Fixes
April 8, 2021
Features and Improvements
- File Formats: Device status of <= -3 when reading an EPC file now means to delete the element. Previously we had been using status = -4 to delete an element. Devices are not actually deleted, but the Flag for Delete in EPC will be set to YES.
- Transient Stability: modified log message that says something like "1012 more ..." to say "1012 more MVABase changed" instead to make it more clear.
- Oneline Diagrams: Fixed an access violation when Auto Inserting buses.
- Transient Stability: Bug fix for OEL5C. State IntegratorTOEL was not being set.
Bug Fixes
April 7, 2021
Bug Fixes
- Oneline Diagrams: Fixed bug saving oneline diagrams. The program appeared to hang when saving oneline diagrams because of some unnecessary calculations for groups. We've fixed the problem by only doing calculation once.
- Transient Stability: SCL1C is now more robust during initialization
- Transient Stability: If Modify Limits is chosen in Transient Stability Options, and if a UEL1 model feeds into a exciter's HV gate, then UEL1 limits VUImin and VULmin are modified to prevent initial limit violations
- Transient Stability: When choosing to either Copy or Print All Charts and Title Block, the Title Block was chosen then the bottom and right gray boundary edge on the image created was missing. This has been fixed.
April 2, 2021
Bug Fixes
- File Formats: Fixed a bug that would cause contingency violations stored by violated element to not appear properly after loading a PWB file. The PWB file still contained them, and after this patch they will be properly shown after loading the same PWB.
- Transient Stability: Fixed a bug with PSS3C not passing the correct parameters and causing an access violation.
April 1, 2021
Bug Fixes
- Sensitivity Calculations: Fixed bug that was causing inconsistent TLR results after sequential power flow TLR calculations. The issue was the inconsistent inclusion of phase shifters in the TLR matrices. This has been fixed by checking if the matrices have been built with phase shifters and rebuilding if needed.
March 31, 2021
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): When specifying a Source or Sink that cannot be found for a Direction object when loading from an auxiliary file, put error message in the log that the Source or Sink will be set to Slack instead.
- Case Information Displays: Added TSContingency string grid table to the customizable tables. Now the customization of the Transient Contingency table can be saved.
- Case Information Displays: Added nine superarea voltage fields showing min/max/avg for pu voltage, voltage angle (degrees) and voltage angle (rad).
- Case Information Displays: Added ability to specify generator voltage setpoint and setpoint tolerance in kV. Added generator field to show the RegBus Nom kV.
- Case Information Displays: Added TSContingency string grid table to the customizable tables. Now the customization of the Transient Contingency table can be saved.
- Case Information Displays: SendToExcel script command will no longer change the workbookname and worksheetname to uppercase.
- File Formats: Added optional parameters filtername and AppendFile to the CTGWriteFilePTI script command. The filter is applied to the Contingency object type to specify the contingencies that should be saved to file. All contingencies are saved by default. Set AppendFile to YES to append to an existing file or NO to overwrite an existing file. File is overwritten by default.
- File Formats: In various places where contingency files in the PTI CON format are saved in the GUI a prompt will appear if the file already exists asking the user if the file should be overwritten or appended.
- Oneline Diagrams: Added an InjectionGroup field.
- Time Step Simulation: Changed time domain simulation so a reset actually resets the time to the start time.
- Transient Stability: New transient stability fields for UEL/OEL/SCL. UEL/OEL dynamic models now have a transient stability integer field called "Activation Status". SCL dynamic models now have two transient stability integer fields called "UEL Activation Status" and "OEL Activation Status". Possible values are 0 (Idle), 1(Engaged) and 2 (Saturated).
- User Interface Dialogs: Added ability to show all area supply or demand curves for a super area.
- Auxiliary Files (SCRIPT and DATA Sections): Corrected generator variable name RegVoltkVError to RegBuskV (it has always showed the actual kV)
- Oneline Diagrams: Fixed bug associated with the display of multiple grouped objects, mostly when at least one of the objects is not a text object, like a background rectangle.
- Oneline Diagrams: Fixed a bug where Snap To Grid was not being returned to its previous value after being temporarily set to True
- Sensitivity Calculations: When using consolidation with a full topology case, calculations for shift factors and PTDFs may not have been correct when using injection groups containing bus participation points as the source or sink. This has been fixed.
- User Interface Dialogs: Fixed bug with TGen.MWLambda when fuelcost + extrafuelcost = zero. This would only affect economic dispatch or the code showing a supply curve so the bug would not be common.
- User Interface Dialogs: Modified generator, area and superarea charts to handle negative marginal costs; also provide access to options so curves can be customized, though right now the change are not stored.
Bug Fixes
March 24, 2021
Features and Improvements
- Difference Case Tool: Custom integer, custom float and custom string fields can now be included or excluded when in difference or change mode. This allows a user to populate these custom fields with values they want to be seen under all Difference Case Modes so that the custom fields act like an identifier for the object. Previously if a custom integer had not changed then in difference mode it would show a zero and in Change Mode it would say _same_.
- Transient Stability: Transient contingencies now have an option to Include RAS for individual contingencies. Previously RAS was always included.
- Difference Case Tool: Expanded and corrected functionality for saving Difference Case elements to EPC file format. Interfaces and injection groups can now be saved as difference case elements. Corrected use of Aux Export Format for saving only records that have changed.
- File Formats: Modified MATPOWER format read to correctly handle more than double circuit lines. MATPOWER itself does not support line circuit numbers, but does allow multiple circuits. The issue was when PowerWorld was not correctly assigning unique circuit IDs when loading a MATPOWER case when their were more than two circuits.
- Time Step Simulation: Fixed some issues associated with Area ED control, including adding support for negative marginal costs. On the Time Step Simulation 1) added an option to not scale the area and zone load based on out-of-service loads, and 2) added the ability to save a pwb file at the end of each time step. Both options are available on the Time Step Simulation, Options page.
- User Interface Dialogs: Fixed bug associated with showing the Switched Shunt dialog from a quickpout in the edit mode when the case has not been in the run mode.
Bug Fixes
March 5, 2021
Features and Improvements
- General: Fixed a bug with line length not been saved when inserting a new branch.