Software Patches

December 11, 2017

Features and Improvements

  • GIC: Adding ability to show GIC results in time step simulation. Also fixed bug with time step timepoint changes.
  • Time Step Simulation: Updated time step summary to show load/gen/shunt results as opposed to input.
  • Transient Stability: Added support for the newer Bradley Governor for Chugach (HGBLEM)
  • Transient Stability: Added ABBSVC1 Switched Shunt transient stability model
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: Fixed a bug that might cause RAS to not implement correctly during the full CTG solution during ATC analysis if the RAS involved Model Conditions using the Evaluate in CTG Ref State or Disable if True in CTG Ref State option.
    • Available Transfer Capability (ATC) Tool: Added FULL_RESERVE_LIMIT as Iteratively Found string for ATC results that end up hitting a reserve limit when using the full CTG solution method. There is also a companion transfer limit that indicates if the source or sink hits the reserve limit and this limit has always existed. Changing the iteratively found string makes it easier to determine that the iterations were terminated because of a limit if they end up getting sorted and you don't see the companion limiter right next to the result.
    • Available Transfer Capability (ATC) Tool: When hitting a reserve limit when using the full CTG solution ATC method and the contingency does not solve at the reserve limit transfer level, go ahead and iterate on the contingency if the option to iterate on failed contingencies is in use. Previously, the iterations would stop at this point and just report the transfer level at which the contingency last solved without providing an indication that the contingency failed.
    • Contingency Analysis: Fixed error that could occur opening the Dependency Explorer if any object available for selection in the explorer referenced a calculated field that was not defined.
    • Contingency Analysis: Fixed a bug where a MON file would hang when read if the last character of the last line of the file was the EOF character instead of a CR or LF. Previously we assumed that every line would have a CR or LF at the end, and that the EOF marker would be on its own line after the last line of text.
    • Contingency Analysis: When solving the DC transmission network equations during the AC power flow solution the same tolerance was being used for the DC equations as for the AC equations. It's important in some situations to ensure that the DC equations are solved more precisely so that the evaluation of the AC power flow mismatch is not off. The tolerance of the DC equations is now always 0.5*AC tolerance.
    • General: Changing the licensing to be more robust in the face of high CPU contention (greatly reducing the propensity for "Pipe read timed out" and thus licensing errors) and also so that the main program terminates more quickly.
    • PV and QV Curve (PVQV) Tool: When using Merit Order dispatch as a contingency action we must set the units dispatched to AGC = NO so that they don't end up moving again during the contingency make-up power calculation (this is correct). However, we were also setting AGC = NO when Merit Order dispatch was used as a ramping method outside of contingency analysis, which was NOT correct. This has been fixed. This would only affect solutions where the AGC status of generators was enforced as part of the injection group using merit order ramping.
    • Transient Stability: Fixed error when a dynamic switched shunt model was assigned to a shunt that was presently out of service in the base case.