Software Patches

June 22, 2021

Features and Improvements

  • Contingency Analysis Tool: Added code to keep unlinked contingency elements when reading OTG contingency files. Previously unlinked contingency actions were discarded.
  • Oneline Diagrams: The Text Object dialog now has a format button to give direct access to the format dialog. This matches what has long been done with the line dialog.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: In ATC when using the (IL) then Full CTG solution method, corrected how a negative stepsize is handled when iterating on a failed contingency and the limiting element is overloaded at a step when the contingency does solve. When iterating on a failed contingency the stepsize is reduced by half if trying to find a transfer where the limiting element is not overloaded. This is incorrect if the stepsize is negative because the stepsize needs to become more negative to reduce the loading on the limiting element. The new stepsize is now (stepsize + stepsize/2) to make it more negative.
    • Available Transfer Capability (ATC) Tool: Fixed a couple of inconsistencies with the ATC solution when using the (IL) then Full CTG Solution.
      (1) When iterating on individual limiters with a contingency implemented, use the OTDF cutoff threshold instead of the PTDF cutoff threshold.
      (2) When iterating on individual limiters with a contingency and an infinite transfer level is reached during the step where the limiter is iterated on by linearly modeling the contingency, no longer continue to the step where the contingency is actually implemented. The result will report Iteratively Found as YES_INFINITE.
    • Contingency Analysis: Fixed infinite loop that might result when using Best Fit actions for contingencies and remedial actions.
    • Transient Stability: Fixed a divided by zero in HYG3 when (fRelec = 0) and (fRGate = 0).
    • Transient Stability: There was an access violation bug when no results are saved into RAM or Hard Drive but saving plots as a file. The problem is fixed.