May 1, 2025
Features and Improvements
- Transient Stability: New stability model names REPCGFM_C1 plant controller which has control algorithm for regulating P, Q, V and Frequency
- Power Flow Solution: When interfaces contain line contingencies that cause buses to become islanded, numerical problems can be encountered with the linear solution used for determining the impact of the contingent elements on the other contingent elements within the interface. This can cause inconsistent results. This has been fixed.
Bug Fixes
April 29, 2025
Bug Fixes
- General: When choosing to "Export Object Fields" to either a text file or Excel when a power system case had not yet been opened, an access violation occurred. This has been fixed.
April 28, 2025
Features and Improvements
- Transient Stability: Added support for a new VSCDCLine model in stability named VHVDC2 which is very similar to VHVDC1
- File Formats: Two-Terminal DC line in PowerWorld Simulator have a field for allowing the user to specify the GE EPC file bus number for the DC terminals of the device. If these are populated with 0 values we should should be automatically choosing unused numbers. This automatic calculation was not working properly and is now fixed.
Bug Fixes
April 23, 2025
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): DoCTGAction script command will now handle OPENCBS and CLOSECBS actions the same way that contingency analysis implements these actions. Previously these actions were not implemented.
- Available Transfer Capability (ATC) Tool: Changed the name of the bus field ATCMinTransLimMW to instead be ATCMinTransLimMWSource (we will still read the old field ATCMinTransLimMW and map that to ATCMinTransLimMWSource).
- Available Transfer Capability (ATC) Tool: Added a new Bus Field named ATCMinTransLimMWSink which returns the minimum Trans Lim value of the ATC Transfer Limiters where this bus is the Sink of the transfer for a transfer direction studied with Multiple Directions ATC and only a single transfer direction has this bus as the Sink. This field matched the field ATCMinTransLimMWSource for the Source
- Oneline Diagrams: Modified the BusView and SubView so that the right-click options for "Open External Maps" will work by getting the latitude/longitude coordinates from the Bus or Substation. Previously those features were never available because the BusView and SubView were not geographic-based onelines.
- Transient Stability: Modified display of the list of PlayIn signals in the Plot Designer so they are sorted in numerical order of the PlayInInfo always. Previously we were sorting like a string so the order was 0, 1, 10, 11 instead of 0, 1, 2, 3 etc.
- Transient Stability: New stability model names REPCGFM_C1 plant controller for use with machine model REGFM_C1 which has control algorithm for regulating P, Q, V and Frequency
- Transient Stability: Added the Ierr signal under the "OEL Other" folder in the plots section for the OEL2C model.
- User Interface Dialogs: Region information is now shown on the geography page for the bus and substation run-time dialogs; region information is also available in the Case Information displays (geography section) for buses, generators, loads, switched shunts, substations, areas and zones.
- Auxiliary Files (SCRIPT and DATA Sections): There was an access violation caused by removing a user named state via script command via the DeleteState script command if the state did not exist. This has been fixed.
- Case Information Displays: The tool to Export Case Object Fields was only reporting fields that had not been translated. This has been fixed again and all fields will be reported now.
- Case Information Displays: Fixed bug calculating generation in an owner. It was including offline generators in the generation sum. A check on the generation status has been added to fix this.
- Time Step Simulation: fixed a time step simulation issue in which some of the input fields were being shown as blank when the inputs had not yet been processed.
- Transient Stability: The OELInput parameter for the OEL2C model in a PSSE DYR file, has acceptable values of 1 (psse default), 2, 3, which are now correctly translated to the values 1, 0, 3 respectively in PowerWorld Simulator. Earlier, this translation was not being done while reading and writing a DYR. Already saved PWB files will be affected, and users will need to reload a DYR file in order to correctly translate this parameter.
- Transient Stability: The SW1 parameter for the OEL2C model in a PSSE DYR file, has acceptable values of 1, 2, which are now correctly translated to the values 0, 1, respectively in PowerWorld Simulator. Earlier, this translation was not being done while reading and writing a DYR.
- Transient Stability: During initialization of OEL2C, if modification limits is allowed, and if OEL ramp rate logic, Z is greater than or equal to zero, then the Iinst upper limit will be modified to match Iact. This is done to ensure that Ierr is greater than or equal to zero, and VOEL initializes to the upper limit, which is consistent with the OEL being idle.
- Transient Stability: Added initial limit modification for VOELmax1 provided the OEL is being initialized as idle. VOELmax2 and VOELmax3 were already being considered, and had missed to do it for VOELmax1.
Bug Fixes
April 15, 2025
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Do not put any restrictions on AXD script commands for being allowed when a load of an AXD file is treated as a complete oneline. Loading as a complete oneline is assumed when using the LoadAXD script command and creating a new oneline at the same time. At this point there seems to be no reason to restrict when AXD script commands can be applied.
- Available Transfer Capability (ATC) Tool: When using the ATC tool to ramp a scenario to the transfer limit for the scenario, the ramping to this transfer limit might fail if there were any iterated limiters that ended up not being able to solve their contingency and fully find the iterated limiter. This has been fixed.
- Transient Stability: REPC_B model were showing the incorrect sign for fdbd2 and possibly fdbd1 and dbd.
Bug Fixes
April 14, 2025
Features and Improvements
- Transient Stability: Added new Hybrid Inverter-based renewable Machine model named REGFM_C1. This model is called a "hybrid" model because it acts as simultaneously a Grid Forming Converter and a Grid Following Converter. This model is in beta development in conjunction with the WECC Model Validation Subcommittee.
- Contingency Analysis: When writing out CON files with REMOVE SWSHUNT or ADD SWSHUNT commands, modified to ensure that the ID string is also written after the SWSHUNT command. We added ability to read these commands with or without the ID several months ago, but when writing we were still omitting the ID string.
- File Formats: When writing out MVA limits D..K for transformer windings to a RAW file we were mistakenly writing out limits D over and over. This has been fixed.
- Transient Stability: The feature for showing Stability Models with bold fonts to indicate non-default values was no longer working. This has been restored.
- Transient Stability: Fixed error which could cause the final point of a PlayInGen voltage/frequency value to be ignored.
- Transient Stability: There was a bug in REPC_C model where the dialog and columns were only showing the first 11 Switched Shunt objects being controlled by the REPC_C and were missing the 12th if it existed. Now this was fixed.
Bug Fixes
April 9, 2025
Features and Improvements
- Contingency Analysis Tool: Two fields were added for Custom Monitors in Contingency Analysis -- Min Value Ctg Name and Max Value Ctg Name, which show the name of the contingency corresponding to the Min Value Cont. and Max Value Cont. respectively.
- Contingency Analysis Tool: For contingency actions that perform InjectionGroup Set/Change MW values by opening generation or load, a single WhatOccurredDuringContingency entry for the InjectionGroup is created indicating how must generation or load has been tripped and the MW Effect if relevant. This patch adds additional WhatOccurredDuringContingency entries listing the specific generator and loads and how much each has changed the MW injection. This doesn't impact the solution, but adds additional useful reporting.
- Data Checks: Could get a "duplicates not allowed" error when trying to open the Data Check tool. This has been fixed.
- General: Regions: provided option to use a much faster way to save the boundary points in aux files. Improved the region form performance with larger boundary point sets.
- Transient Stability: Added a new transient option called "Allow Creation on Dialog of Faults which Calculate Effect Impedance from Sequence Networks (Not Recommended)". The use of this option is not recommended. When choosing it, you will be able to create fault actions that calculate the effective impedance from the sequence networks. We do not recommend this because most of our users running transient stability do not have sequence network information available and instead make use of features such as applying a given fault impedance or applying a fault to achieve a per unit voltage.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug in the code for reading three winding transformers from an Auxiliary file. We were getting an access violation when a three winding transformer was read that was considered new, but had a duplicate star bus listed as an existing three winding transformer. This requires us to create a new star bus and that was causing an access violation in Simulator. This is now fixed.
- Available Transfer Capability (ATC) Tool: When using one of the iterated ATC methods and the source and sink are injection groups, participation factors will remain constant throughout the analysis even if participation factors are set to be auto calculated. The assumption is they should only be auto-calculated once at the start of running the ATC.
- Data Checks: Could get a "duplicates not allowed" error when trying to open the Data Check tool. This has been fixed.
Bug Fixes
March 31, 2025
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Added a new script command DirectionsAutoInsertReference(SourceType, SinkObject, DeleteExisting, SourceFilterName, OppositeDirection);
SourceType : Bus, Area, Zone, or InjectionGroup
SinkObject: "Slack", or the objectname plus keyfield or label identifiers for a specific Bus, Area, Zone, or InjectionGroup
DeleteExisting: YES or NO
SourceFilterName: a string showing the name of a filter for which Source objects to use
OppositeDirection: YES or NO - Available Transfer Capability (ATC) Tool: Modified the Auto Insertion of Directions dialog to allow the user to specify if the Reference is the Sink or the Source. Previously the Reference was always the Sink. For doing studies of transferring power to large loads it is useful to do the opposite.
- Auxiliary Files (SCRIPT and DATA Sections): The tool to Export Case Object Fields was not properly working. This has been fixed and all fields will be reported now.
- Simulator Automation Server (SimAuto): Updated SimAuto's GetSystemMetrics to correctly report logical processor counts on machines with >64 cores
Bug Fixes
March 25, 2025
Bug Fixes
- Auxiliary Files (SCRIPT and DATA Sections): When loading Model Expressions from auxiliary files the expressions were not properly initialized. This resulted in this error reported with each expression: "ERROR: Expression object not created." This has been fixed.
March 24, 2025
Features and Improvements
- Oneline Diagrams: Added an option to allow the user to specify the amount of spacing between parallel lines on the auto line insertion.
- User Interface Dialogs: Added a few new fields to the Regions dialog; also added field to show the regions associated with a bus.
- Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with loading 3WXformer objects from an Auxiliary file. Objects would not be found correctly.
- Available Transfer Capability (ATC) Tool: When using an iterated method with ATC analysis and the full transfer step is not able to be achieved in the part of the process where all limiters are iterated on to determine the order in which individual limiters will be iterated on, the remaining limiters that are not iterated on individually might have their Trans Lim values increased incorrectly by the amount of transfer that was able to be achieved in the last step of the initial process when the POWERFLOW DIVERGENCE limiter is recorded. This has been fixed.
Bug Fixes
March 21, 2025
Features and Improvements
- Case Information Displays: Added a new field CountTransformer (Number Of\Transformers ) for both a Bus, Zone, Area, and Substation object to show the number of Transformers attached to the Bus, or at buses inside the groupings.
- Case Information Displays: Added new fields for a Bus object named ZBRGenList, ZBRRegBusList, ZBRRegBusConflict, ZBRVoltSetList, and ZBRVoltSetConflict. These fields are then shown on a new case information display available in the Model Explorer under Solutions Details\Regulating Buses Multiple Local. The fields are populated with information when grouping of buses connected by low impedance branches have multiple generators connected to them. They will then show a list of bus number of regulated buses and a list of voltage setpoint voltages, and if there are multiples of these representing a conflict field will say YES. This can be helpful in debugging conflicting input data that is not as obvious as generators at the same bus having different regulation buses or setpoints.
- File Formats: Simulator Version 24 reads the RAW file field for a Branch and Transformer called NAME as an object label. For many years, PowerWorld has also seen RAW files in particular written out of EMS systems that included special syntax inside of Comment strings at the end of RAW file records. These comments included an object label inside of square brackets. This ad-hoc syntax had been used for years by customers to include labels. The original release of Simulator 24 read both of these locations as a label, but the NAME field was given priority and set as the Primary Label inside Simulator. Users however are finding that the values in the comment are more predictably set as labels, so we have changed it so the ad-hoc syntax in the comment string is set as the primary label instead.
- Oneline Diagrams: When reading a Shapefile (*.shp) into a oneline, Simulator will now look inside the PRJ file (if available) at the PROJECTION specified. If the PRJ file has a PROJECTION equal to "Mercator_Auxiliary_Sphere" then Simulator will automatically assume it map projection that is very commonly used for Shapefiles associated with website platforms such as Google Maps, Bing Maps, and so on. When this is detected now, Simulator will automatically convert the coordinates in the SHP files to Latitude/Longitude coordinates using this assumed map projection. In older versions of Simulator the user could click a button on the Modify Tab of the Shapefile import form, but this will now be done immediately upon loading the file.
- Oneline Diagrams: Fixed bug when loading a Shapefile (*shp) if a companion Projection file (*.prj) did not exist. The PRJ file should not be required when reading the SHP file, but an error would appear saying that the file could not be found.
Bug Fixes
March 18, 2025
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): The DetermineShortestPath script command was not correctly reading the parameter for BranchDistanceMeasure resulting in a returned error. This has been fixed.
- Contingency Analysis Tool: Fixed linear methods for calculating contingency actions for setting or changing an injection group in merit order. Actions using merit order open were correctly implemented.
- Contingency Analysis Tool: When using linear methods for calculating contingencies, the accounting of the gen or load dropped by injection group Set To and Change By actions used when reporting results was not correct. This has been fixed.
- File Formats: The features added over the last couple patch related to the problem in many RAW files where disconnected generators, loads, and shunt were still providing MW and Mvar to the system has been confirmed as a known problem in the RAW file solutions. This patch modified the dialog appearing telling the user about this problem so the dialog is informational only. PowerWorld will now always close in switching devices to replicate the MW/Mvar flows of the incorrect RAW file solution.
- GIC: Mostly minor changes, including 1) updating the GMD code to show support for TLP-007-4, 2) starting to add support for the new geomagnetic north pole locations, 3) support for viewing GIC files in the file browser, 4) adding an automatic upload of the region buses when they are loaded from an aux file.
- User Interface Dialogs: Added support for user interaction with the Message Log using the Mouse Wheel and keyboard UpArrow, DownArrow, PageUp and PageDown keys.
MouseWheel up and down will scroll the messages log without changing selection.
Ctrl+MouseWheel will zoom in and out (change font size).
Shift+MouseWheel will expand the selection up or down by one row.
Up/Down Arrow will move the selection up/down one row.
Shift+Up/DownArrow will expand the selection up/down one row.
Ctrl+Up/Down will zoom in and out (change font size).
PageUp/PageDown will move the selection up/down the number of visible rows.
Shift+PageUp/PageDown will expand the selection up/down the number of visible rows.
Ctrl+PageUp/PageDown will zoom in and out faster (change font size).
March 14, 2025
Features and Improvements
- Case Information Displays: When right-clicking on a case information display and choosing "Set all Values To", the dialog box that appears will now automatically have the edit box for entering a value focused so you can immediately start typing the number.
- Case Information Displays: Fixed various location where copy/pasting the Latitude and Longitude field into a table was not working.
- Case Information Displays: Generator, Load, and SwitchedShunt objects were not working when copy/pasting (or loading from a CSV) because it would say the key fields were missing, even though the ID field was there. This was NOT impacting auxiliary files, but was unique bug to copy/pasting (or loading from a CSV) which were based on column headings.
- File Formats: The March 12, 2025 patch of Simulator 24 had a bug that would impact the ability of the March 5, 7, and 10 patches ability to read the PWB file produced. The PWB file would still read find in the March 12 patch of Simulator 24, but not the previous patches of Version 24. This patch fixes it so PWB files created are read correctly by all Version 24 patches.
- Transient Stability: Eliminated a validation warning message for svsmo1,2 and3 about "The transient Xc parameter is different from the power flow Xc value". This message was created by mistake, even when the parameters were the same. If they are different values, that is handled in the initialization of the model and do not need a validation warning. The validation warning was removed from every situation.
Bug Fixes
March 12, 2025
Features and Improvements
- Auxiliary Files (SCRIPT and DATA Sections): Updated the Move script command to accept labels to specify the branch and also accept a bus label instead of a bus number for the destination
- File Formats: The Limit Monitoring option for "Do not monitor radial lines and buses" is no automatically reset to unchecked when loading a new RAW or EPC file. Previously it would remain at whatever setting it had before opening the RAW or EPC file.
- File Formats: In the previous patch, features were added when loading a RAW file that were locating incorrect treatment in RAW file solutions if FixedNumBus with a mixture of Connected and Disconnected substation node statuses. This patch introduces features to automatically determine switching devices that could be closed to match the incorrect RAW file solution and prompt the user asking them if they would like us to close these switching devices.
- Oneline Diagrams: Added Region Display Styles for creating automated oneline displays from geographic Region objects.
- Transient Stability: When a vertical axis is set to ScaleMinAuto and ScaleMaxAuto the axis extremes are calculated automatically, however PowerWorld has always internally ensured that the range at least shows a variation in the 5th significant digit. A new option has been added to allow the user to specify a ScaleAutoRangeMin. This will ensure that the auto extremes calculated are enforce that (AutoMax - AutoMin) >= ScaleAutoRangeMin. If the range is less than this then the new range will be set to the average of the AutoMax and AutoMin plus/minus the ScaleAutoRangeMin/2.
NewAutoMax = (AutoMax + AutoMin)/2 + ScaleAutoRangeMin/2
NewAutoMin = (AutoMax + AutoMin)/2 - ScaleAutoRangeMin/2 - Transient Stability: When ScaleMinAuto and ScaleMaxAuto are both set to YES and the user sets a value for ScaleInc, modified so that the maximum value used for an increment will be (Max-Min)/2 so at a minimum 3 points will be labels on the vertical axis. This prevents situations such as ScaleInc being set to 0.05 when the automatically determine Max is 1.02 and Min is 1.01 which would create a Y-axis without any scale because the increment was too big.
- Oneline Diagrams: The local menu when right-clicking on a branch display object on a oneline shows the From and To bus numbers listed at the top of the menu. The "To:" was not propertly showing the To bus but was instead just repeating the From bus. This has been fixed.
Bug Fixes
March 10, 2025
Features and Improvements
- File Formats: PowerWorld has found many RAW files with FixedNumBus groupings with a mixture of Nodes with Connected and Disconnected Status. At some of these nodes with Mixed Status, there are generator, load or shunt objects that meet the following criteria (1) Terminal is at a disconnected node, (2) device status = 1, and (3) MW or Mvar injection exists. Because the terminal nodes are disconnected for these devices by substation switching devices, they can not provide injection to the system. PowerWorld has found many RAW file solutions that have these disconnected devices supplying or absorbing power. Various messages log information is now displayed when this is encountered along with recommended switching devices that can be closed to replicated the RAW file solution.
- Transient Stability: Implemented a new UEL2CPTI model, that is created when reading in the UEL2C model record in a PTI DYR file. This new model has extra model parameters compared to a UEL2C model GE DYD file -- (i) an extra 11th pair (P10, Q10) in the lookup table, (ii) an extra limit pair (VULmax/min) on the VUEL output signal, and (iii) an extra parameter (Quad) that allows the lookup table to be used as mirrored around the MVAR axis when MW values are negative. This extra parameters are read/written from the text formats, and the are fully implemented during the dynamic simulation.
March 7, 2025
Features and Improvements
- Bus View and Substation View Onelines: Added a new visualization for Bus View to show "Consolidate FixedNumBus Splits" which will generally show FixedNumBus groupings but will automatically split up those groupings if there are multiple Superbus within the group. This ensures that the user can always see open breakers that have split the FixedNumBus
- Bus View and Substation View Onelines: Modified the "Consolidated Superbus" BusView to highlight other SuperBus which would be part of the Superbus if switching devices were closed or other things preventing consolidation were ignored.
- Bus View and Substation View Onelines: Modified the "Consolidated FixedNumBus" BusView to visualize the splits created by the open switching devices.
- Case Information Displays: A new field was added to a Bus, Gen, Load, and Shunt object called Solution\Status FixedNumBus. Shows either Disconnected, Connected, Mixed, Connected2, Mixed2, and so on. If all buses in the FixedNumBus are Disconnected it will show Disconnected. If all are Connected, then it will show Connected followed by the number of unique SuperBus that are inside the FixedNum Bus if more than 2. If there is are both Connected and Disconnected buses, then it will say Mixed.
- File Formats: When loading in other file formats, PowerWorld would set a bus' voltage could be set equal to another bus if it was radial to the other bus and also had no load, generation, or shunts. This improved solution convergence is cases written in other file formats. A message log is now written indicating this is happening.
- Transient Stability: Added support to read and write to a dyd file for the transient models OEL4C and OEL5C.
- Transient Stability: On generator dialog when adding a model the dialog which appears had the "folder icon" and the "blue dot icon" flipped. This has been fixed
- Transient Stability: Access violation bug when using certain system or groups transient model (like system wide WSCC load model) and opening a table of the transient models in the Model Explorer. Now the access violation will not occur.
- User Interface Dialogs: Changes were made to the look and feel of the selected text in the Message Log in Simulator 24. These changes caused the font size of the message log to be ignored and unchangeable. This has been fixed.