Software Patches

December 18, 2015

Features and Improvements

  • Contingency Analysis Tool: When displaying LODF/LCDF calculations as part of the Contingency Sensitivities tool, if a branch causes the island topology to change, 'Island Change' will be reported instead of the LODF/LCDF and all other values will be blank. The Contingency Sensitivities Tool is available under the right-click menu of a particular contingency violation.
  • Contingency Analysis Tool: Added ability for the variables of an Expression to have a flag indicating that the value should be evaluated in the contingency reference state. This then allows you to create an Expression which is a function of both pre and post contingency variables.
  • Contingency Analysis Tool: Added ability for the variables of a ModelExpression to have a flag indicating that the value should be evaluated in the contingency reference state. This then allows you to create a ModelExpression which is a function of both pre and post contingency variables.
  • Contingency Analysis Tool: Add ability for the variable being evaluated in a ModelConditionCondition to specify that it be evaluated in the contingency reference state. As an example that would use this, a single ModelCondition can be created that checks two ModelConditionCondition on a Branch Object as follows.
    1. Status = Closed IN REFERENCE
    2. Status = Open
    This makes it easier to create logic to evaluate a change from the reference state.
  • Oneline Diagrams: Added ability for showing dialogs for Generators, Loads, and Branches when right-clicking on the various background lines shown on Areva DDL oneline diagrams inside Simulator.
  • PV and QV Curve (PVQV) Tool: Added popup hints for all the various options on the PV Curve dialog (simular to what has already been done for the Contingency analysis and Transient Stability dialogs a few years ago)
  • Simulator Automation Server (SimAuto): Modified so that when running a SimAuto instance we never write the list of Recently opened files to the registry. This should only be modified when opening files in the user interface
  • Transient Stability: When loading in TSPlotVertAxisGroup objects from a Version 18 and earlier PWB file, if the axis group contained ALL generator speed plot series AND the user had user-specified Min/Max values on the vertical axis scale, then these values were based around nominal frequency. In Version 19 however, we now store generator speed in per unit instead of scaled by nominal frequency. To fix potential troubles with vertical axis groups on plots, we will now automatically scale the user-specified min/max value in this situation.
  • Transient Stability: Modified DEGOV1 to not enforce any contraint on the size of the T3 and T4 time constaints. Also modified so that validation enforces that TD must be no larger than 12*TimeStep
  • Transient Stability: Fixed error in loading the SVCBAS USRMDL from a PTI DYR file. It wasn't reading the regulated bu terminal correctly.
  • Bug Fixes

    • Distributed Computation: When running distributed computing tools it is possible for multiple instances of Simulator to close simultaneously and then try to write to the windows registry all at the same time. This was causing a conflict resulting in dialogs appearing indicating you can't write to the registry. This has been fixed by not writing to the windows registry from a SimAuto instance that was launched by PowerWorld's distributed computing tools.
    • Distributed Computation: When running distributed Transient Stability, Simulator was going through and validating the transient stability models for every contingency. This is unnecessary, and it is only necessary to validate against the largest time step, so now validation is only done once on the largest time step.
    • Distributed Computation: When running distributed Transient Stability, Simulator was continuing to write TSR files even when the user had chosen not to store to hard drive or to RAM (you might do this if you were only looking at the transient limit monitors.) This has been modified for now so that a TSR file is still written but it is configured so it doesn't store anything (it will be about 4 KB). We will likely remove this shortly as well.
    • Power Flow Solution: Fixed an issue with min and max of svcs that provide continuous Mvar control. In some situation they would become stuck at their min or max limit and not back off the limit when appropriate.
    • Simulator Automation Server (SimAuto): Added additionally checking to ensure that only one instance of SimAuto can write to the registry at a time.
    • Transient Stability: When writing an AUX file containing the Min/Max results for generators, some switched shunts that model SVCs were being included in this AUX file. These have been removed.