Software Patches

July 20, 2015

Features and Improvements

  • Contingency Analysis Tool: Added fields to display owner names and numbers with contingency elements.
  • Contingency Analysis Tool: Added ability of Limit Violations to show the Custom Float, Integer, and String fields associated with the overloaded object. This is available on both of the following tables:
    1. Table showing the violations for only one contingency (on Contingency tab of dialog)
    2. Table showing all contingency violations (on Results tab of dialog)
  • File Formats: Modified reading the "Promod" format for defining interfaces so that we look for the keyword "BASECASE" and treat it the same as "BASE" was treated before.
  • Transient Stability: Added additional features to the "Insert Apply and Clear Fault" button on the transient stability dialog. Previously when doing this we did the following:
    Branch fault: create 3 events: Fault, OpenFrom, and OpenTo
    Bus Fault: create 2 events: Fault, ClearFault
    We have now modified it so that the user may choose whether to "Clear Fault" or "Open" for the extra events.
    Note: The auto-insert transient contingency tool will always do OPEN for all extra events.
  • Transient Stability: modified the REEC_A, REEC_B, and REEC_C models so that when pfflag = 1 (constant power factor), then we initialize Qext to 0.0.
    It really doesn't matter in this particular situation because Qext isn't used if pfflag = 1, but it is less confusing when connected to an REPC_A model if it defaults to zero in this situation.
  • User Interface Dialogs: Added menu options for Append Case to directly access the different file types from the dropdown menu.
  • Bug Fixes

    • Contingency Analysis: Fixed access violation that could occur when viewing contingency elements for actions involving gens, loads, or shunts but the action is defined with the bus instead of the specific object.
    • File Formats: When reading a UCTE file, modified how the tap ratios were begin calculated from the ##R records in a UCTE file. Previously for tap ratios, if the ##T record "Rated Voltage 1" and "Rated Voltage 2" did not match the terminal bus nominal voltages, then the tap ratios being read were not handle quite correct.

      The Simulator "Tap Ratio" column shows the tap ratio converted to the system base, while the UCTE file tap ratios described in the ##R records are the transformer base voltages. These were not being properly scaled when reading the ##R record. Also keep this mind if you compare the tap ratios you calculated in the UCTE file to those shown in Simulator. When doing this comparison you need to keep two things in mind:
      1. Simulator always assumes the variable tap is on the FROM bus side of the transformer. The UCTE file assume it is always on the TO bus side, so that tap ratios will be the reciprocal of one another.
      2. Ratios will only match if you compare the "Transformer BaseTap Ratio" value in Simulator which shows the tap ratio of the transformer on the transformer base instead of the system base.
    • File Formats: When reading a UCTE file, added ability to read the phase angle shift values from the ##R records. Previously they were being ignored and all phase shifts were being set to zero. One important note when comparing angles you see in Simulator. Simulator always assumes the variable phase is on the FROM bus side of the transformer while the UCTE file assumes it is always on the TO side, so the angles read in Simulator will have the opposite sign convention.
    • File Formats: Fix a bug that was preventing the opening of some cases when the slack bus of an area did not belong to the area to which the bus belonged. Simulator ignores this specification when it is not consistent, but an access violation was occurring related to writing this warning message out to the log.
    • Oneline Diagrams: Various fixes with the Geo Data View features.
    • Simulator Automation Server (SimAuto): When closing an instance of Simulator using SimAuto, previously the various options in Simulator which are normally stored to the Windows registry were not stored. This includes settings like Distributed Computing and Keyboard shortcuts, but other things as well. Now when closing an instance of Simulator in SimAuto the behavior will be the same as though you closed from the traditional graphical interface.
    • Transient Stability: fixed an error in with loading older version 16 PWB files which store transient stability contingency results. This will only occur when loading version 16 files into Version 17 or 18. This new patch will load these older files correctly now.
    • Transient Stability: Made changes to LHFRT way of handling the user input data. They frequency deviation are given in Hz but were previously being interpreted as per unit.
    • Transient Stability: Fixed reporting of a limit violation on GPWSCC model when Ki = 0. It was reporting a limit violation even though the state was ignored.
    • Transient Stability: When checking a limit against a min/max limit pair, sometimes Simulator would report a state violation even when the value was exactly at the limit. It will now only report limit violations to the user if they exceed the limit by more than 0.01% of the limit. Thus if the max limit is 1.0000 then it will only report a limit violation if it's 1.0001 or higher. Note, this ONLY effects the reporting of limit to the user. The value is still pegged at the limit, but we just don't report state limit violations that are likely due to numerical precision.
    • Transient Stability: Fixed various column headings in transient stability models which were not unique. This will only effect you if you were creating stability models by copying and pasting from Excel. Otherwise these are purely cosmetic bug fixes.