Software Patches

November 21, 2017

Bug Fixes

  • File Formats: Fixed error when saving interfaces with unlinked elements to a PWB file. They were not being correctly counted in the number of elements to save but they were still being saved in the file. This would cause an error when loading the file back in. When loading files that have been saved incorrectly it should be possible to recover them by manually intervening where the errors occur on load.
  • Power Flow Solution: When solving island based AGC, MW limits for the system slack bus were not being enforced correctly and this could cause extra MW loop iterations of the overall power flow solution without actually adjusting the island slack within its limits. This has been fixed.
  • Power Flow Solution: When solving areas or super areas on participation factor control, MW limits for the system slack that is part of the area or super area will be enforced if all appropriate MW enforcement options are selected. If the slack happened to be set to a limit but the amount of change was less than the area or super area tolerance, the change would not be redistributed to the rest of the group. Now this change will be redistributed as long as it is greater than 2 times the MVA convergence tolerance. This might help to prevent extra MW loop iterations.
  • Transient Stability: Added a new parameter to DISTRELAY and DISTRELAYITR (FarRelayEnd). Since now the DistRelay determines how to coordinate with another relay by only using the desired branch and the device id there needs to be a mechanism for specifying the coordination the old way. This new parameter is set to 0 (Default) means it will look for the Far Relay Device to be at a different end from this device location end plus the Device id; 1 means it will look for Far Relay Device and only will look for the Device id (The device end will not matter).