Software Patches

February 13, 2018

Features and Improvements

  • Transient Stability: When reading a DYD file, modified parsing of the EWTGFC model so that the last 7 parameters are optional and if omitted will assume the following values: Xc=0, Kqd-0, Tlpqd=0, Xdq=0, Vermn=-0.1, Vermx=0.1, Vfrz=0.7.
  • Transient Stability: When reading a DYD file, modified parsing of the LSDT2 model to allow as few as 5 input parameters to be specified with all subsequent parameters assumed as 0.
  • Transient Stability: When reading a REEC_B record from a DYD file we expect to see 30 input parameters after the colon. This record does not support the mva=12.34 syntax as other records sometimes do, however sometimes we see DYD records which start with the mva=12.34 syntax followed by 29 parameters. In this situation it is reasonable to assume that this first parameter should have instead just been 12.34. We have added special processing of the REEC_B record to support this with a warning message written to the log to indicate this has been assumed. Previously we would have just ignored this record completely and reported an error.
  • Transient Stability: REPC_A and REPC_B models would spit out validation errors when they were configured to measure a branch P, Q, or I and no branch was specified on which to perform this measurement. PowerWorld's hope was that by making this an error which prevented the running of transient stability, this would force the input data to be updated over time, however after a few years it has become clear that this error just confuses folks and the input data has not been updated. We have modified it so that this is now a warning and indicates to the user that all input of IBranch, QBranch, and PBranch will be assumed to be zero until the data is updated.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Slightly modified how the SendToExcel script command sets up a connection to Excel to make it less likely to get a connection and then have Windows subsequently close that connection resulting a Window COM error. Note that it remains dangerous to make repeated called to the SendToExcel script command as this sets up Window COM timing issues with opening and closing Excel in the background. It would be better to use a direct COM connection to Excel that the user manages instead.
    • Difference Case Tool: Unlinked participation factors in an injection group could cause "Duplicate not found" errors when using the Difference Case tool to compare cases. This has been fixed.
    • Oneline Diagrams: When choosing to recalculate the Contour from the toolbar, sometimes as access violation would occur. This has been fixed.
    • Scheduled Actions: When returning actions by using normal status, check to see if the action is active by checking the resolution window if one is in place. Previously we had been ignoring this and returning the action as long as the view time was outside of the time of the action.