Simulator 22 Patches

New Features

Bug Fixes

Date

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

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
  • Bug Fixes

    • 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.

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
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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).

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • Transient Stability: Made initialization of SCL2C more robust.

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.
  • Bug Fixes

    • Oneline Diagrams: Fixed an access violation when Auto Inserting buses.
    • Transient Stability: Bug fix for OEL5C. State IntegratorTOEL was not being set.

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.
  • Bug Fixes

    • 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.

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.
  • Bug Fixes

    • 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.

March 5, 2021

Features and Improvements

  • General: Fixed a bug with line length not been saved when inserting a new branch.