Simulator 21 Patches

New Features

Bug Fixes


August 28, 2019

Features and Improvements

  • User Interface Dialogs: When defining Model Conditions and Model Expressions and using the Choose a Field dialog to select a field for the condition or expression, there is now an option "Show Transient Stability Remedial Action Fields". When this option is checked, only the fields that are valid for being evaluated each time step during transient stability analysis will be shown.
  • Bug Fixes

    • Contingency Analysis: Certain categories of contingency violations could not be loaded from an auxiliary file or correctly returned when using distributed contingency analysis. These include the Change Bus dV/dQ, Change Bus Disconnected, and Bus Neg dV/dQ violation categories. This has been fixed.
    • Contingency Analysis: An access violation could occur when deleting contingency violations from the following categories: Change Bus dV/dQ, Change Bus Disconnected, and Bus Neg dV/dQ. This has been fixed.
    • Distributed Computation: For Distributed Contingency Analysis an error would occur when including the Advanced Limit Monitoring options to "Report changes in bus dV/dQ sensitivity" or "Report as a violation if a bus becomes disconnected." This has been fixed.
    • General: Updated autoload function. Now the files are renamed with an underscore '_' character before being loaded. This allows us to check for files that need to be deleted before loading a new file.
    • Sensitivity Calculations: Fixed access violation when calculating interface sensitivities on the Flow and Voltage Sensitivities dialog under Single Meter, Multiple Transfers.

August 26, 2019

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): When loading Contingency Elements, Remedial Action Elements, and Global Actions from an auxiliary file it was possible that the Model Criteria field could be set to an incorrect entry if the Model Criteria field was not specified in the field list in the auxiliary file. The Model Criteria should have been set as blank instead of an entry. This has been fixed.
  • Auxiliary Files (SCRIPT and DATA Sections): When loading Remedial Action Elements from an auxiliary file it was possible that the Arming Criteria field could be set to an incorrect entry if the Arming Criteria field was not specified in the field list in the auxiliary file. The Arming Criteria should have been set as blank instead of an entry. This has been fixed.
  • Auxiliary Files (SCRIPT and DATA Sections): It was possible that blank names could be specified for Model Filters, Model Conditions, Model Planes, and Model Expressions when loading from an auxiliary file. A non-blank name must be specified for these objects. This has been fixed.

August 23, 2019

Bug Fixes

  • Transient Stability: Handled strange input data for WTGT_A when Ht=0. Modified to automatically assume this represents a single-mass model and internally H=Ht+Hg. Previous expectation was that the user would set Ht and then make Hg=0. This handles situation when the user does the opposite and sets Ht=0 while giving a value for Hg.
  • Transient Stability: Fixed bug when REPC_B was assigned to a generator and then not connected to any generators. This was causing inconsistent results. The expectation is that the REPC_B model must connect its output to itself.
  • User Interface Dialogs: When editing the MVABase of the winding of a three-winding transformer on the Three-Winding Transformer Information dialog it was not taking any edits of the MVABases. You were only able to edit those values on the case information displays and NOT on the dialog. That has been fixed.

August 19, 2019

Features and Improvements

  • Transient Stability: Added a button on the Options > Remedial Actions page of the transient stability dialog to "Show Valid Remedial Action Fields" that will display a case information display with all fields that can be evaluated each transient stability time step.
  • Transient Stability: Added REGC_C model.
  • Bug Fixes

    • File Formats: Modified how the System-Wide settings of the RAW version 34 file are read so that we properly read files even when particular parameters are omitted in that format. Previously we were failing to read the file when values are omitted. The values are all entered as "Key=Value" strings, so we can just parse these and lookup the keys that we fine.
    • Transient Stability: Renamed governor model GGOV1DU to GGOV1D.
    • Transient Stability: When including remedial actions in transient stability, the remedial action definitions would be ignored if not using the option with contingency analysis to "Save contingency analysis definitions/results in the case PWB file." This has been fixed.
    • Transient Stability: Fixed TSAutoInsertDistRelay script command. Added parameters for AddTo, AddFrom, Transfer Trip, and Shape. The format is now:
      TSAutoInsertDistRelay(0.9,InsertRelayAtFromBus, InsertRelayAtToBus, DoTransferTrip, Shape, filtername).
    • Transient Stability: Improved validation of remedial actions used in transient stability.
    • Transient Stability: Added fields that are allowed to be evaluated at each transient stability timestep: Branch MW From, Branch MW To, Branch Mvar From, Branch Mvar To, Branch MVA From, Branch MVA To, Branch Amps From, Branch Amps To, Bus PU Volt, and Bus Volt (kV).
    • Transient Stability: Fixed a bug that would not correctly identify line relay models when loading from an auxiliary file.

August 13, 2019

Features and Improvements

  • General: Added ability to automatically load a PWB, AUX, RAW, or EPC file whenever a new file appears in a directory. The file will immediately be opened and then the file will be deleted!
  • Bug Fixes

    • File Formats: Modified the Save RAW with Options dialog to allow Version 34 RAW files to be opened and saved.
    • File Formats: When reading an EPC file load record a climate zone of " " (double quote, space, double quote) was being read and a climate zone created without stripping of the double quotes resulting in a very strangely named LoadModelGroup in Simulator. Then on a subsequent export of the load record to an EPC it would encase that entire string inside double quotes resulting in "" "". This then appeared to be two strings on the next import of the EPC file messing up entries after the climate zone in the EPC file. This has been fixed.
    • Integrated Topology Processing (ITP): Added checks for the ITP add-on when using the 'When using Integrated Topology Processing, monitor only the primary bus for each superbus' option. This option was being used when the user did not have the ITP add-on and when the case was not marked as a full topology case. This was causing the contingency analysis to give confusing results: they were being limited to primary buses when this was not the expected behavior. Now, the option will check that the user has the ITP add-on and that the case is marked as a full topology case before filtering the results. In addition, the checkbox will be hidden if the user does not have the ITP add-on.
    • Transient Stability: When testing to see if the Intermountain Power Project (IPP) DC Line should be automatically included in the stability model, modified so this model is not included if the actual device is out of service in the initial case. This was causing access violation.
    • Transient Stability: Fixed bugs with initializing a DC line that is out of service in a transient stability simulation.
    • Transient Stability: Fixed error when initially energizing a bus with a ZIP load by closing in branches to energize the bus during a transient stability run.

August 9, 2019

Bug Fixes

  • Transient Stability: Fixed a bug where Plot images were not being saved properly during Distributed TS runs.

August 8, 2019

Features and Improvements

  • Transient Stability: Added a new Injection Group transient stability model named GroupMSS.
  • User Interface Dialogs: Modified the dialog that appears offering the user the ability to add "Case Comments" when choosing options to Save Case, Save Case As, Save Case with Comments, or Save Case As with Comments. Previously once you got to that dialog there was no way to "Abort the Save". Hitting the X in the upper right would just skip adding the comment but you would still save the case. There are now separate buttons to Add a comment, Skip adding comment, and Abort Save all together. Also removed the X in the upper-right of this dialog to force the user to choose one of the buttons making it very clear what is desired.
  • Bug Fixes

    • Case Information Displays: Fixed an access violation that could result when using the option to Export Case Object Fields related to the new ModelPlane object
    • Transient Stability: Bug fix in Modal Analysis for catching exception during floating point overflow, which happens rarely, but typically while using a large time window, or a time window which has a "discontinuous" signal (like when a generator opens up, causing a sudden change)

August 6, 2019

Features and Improvements

  • Transient Stability: Added WTGT_B mechanical model for a type 4 wind turbine.
  • Bug Fixes

    • Case Information Displays: Fixed error in calculating the amps of a load when the load is disconnected.
    • Transient Stability: When an IEEEG1 or CRCMGV were configured with the low pressure generator online AND the high pressure generator off-line, this resulted in an access violation. The governor model is assigned to the high-pressure generator which is off-line in this situation and was causing bad behavior. For now this has been fixed by ignoring the governor and thus the low pressure genenerator will be simulated without a governor.
    • Transient Stability: Added storage of the option to Include Remedial Actions in Transient Analysis to PWB files which will also allow this option to be included with distributed computing. Remedial actions had not been included with the distributed computing runs but this has been fixed.

August 2, 2019

Features and Improvements

  • File Formats: Added bad data handling when reading an EPC file with a generator with cont_mode = 4 if the Vcsched is set to an unreasonable value. (We were seeing cases where value was set to 24.000 as user entered value in kV mistakenly). When Vcsched is specified outside the range 0.85 - 1.15 we will instead assuming cont_mode = 0, the regulated bus is the terminal bus, and the VoltSet is the present terminal voltage.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: Fixed Access Violation that would occur when using the Available Transfer Capability tool when using the Iterated Solution Methods. This bug only impacted Version 21.
    • File Formats: Added ability to read the cont_mode = 4 from a generator in an EPC file. This then uses a field "Vcsched" field. When reading cont_mode = 4, the generator is set to as follows
      VoltSet = Vcsched
      UseLineDrop = YES
      Rcomp = RcompEPC * SBase/MVABase
      Xcomp = XcompEPC * SBase/MVABase
    • Time Step Simulation: Fixed bug when using a file Data Source on the Model Analysis Form when no plots have been defined. Even though the plots is not being used as the source an error would occur. Now a file can be specified without needing plots defined as well.