Software Patches

July 10, 2013

Features and Improvements

  • GIC: Adding a dialog for specifying values for a GIC transformer dialog to make user entry easier.
  • Scheduled Actions: Added ability to use a "Scheduled Action" filter on a case information display showing a list of "Scheduled Action Groups".
  • Transient Stability: The switched shunt SVC power flow model has a Xc parameter. There dynamic model also has an Xc parameter. If these are different this will cause a problem when running a stability simulation. Validation will change the transient stability model to match the power flow model Xc.
  • Transient Stability: If a switched shunt model is NOT marked as an SVC in the power flow, but has an active transient stability SVC model (svsmo1, svsmo2, svsmo3), then this will be treated as a validation error and the stability run will not be allowed to run.
  • Transient Stability: Added a feature with induction motors (loads) and induction machine (generators) so that whenever the per unit speed drops below 0.1, then the entire integration time step will be reduced. A multiplier will be defined that is 0.05 at 0.0 per unit speed and increases linearly up to 1.0 at 0.1 per unit speed. The time step used by the integration will be equal to the user-specified time step multiplier by this value. If multiple motors/machines are operating in this region, then the smallest multiplier in the case will be used. This is intended to improve induction motor starting studies without the user having to manually reduce the time step for the entire simulation. It will be a very rare event when this occurs.
  • Bug Fixes

    • Integrated Topology Processing (ITP): When saving a full topology model out to a consolidated case and merging shunts into blocks, there was an error if the merged shunt ended up with more than 10 blocks. This has been fixed.
    • Transient Stability: When copying a plot and title block and not displaying the date and time, the date and time should not show up in the copy. This has been fixed.
    • Transient Stability: Fixed error in not properly setting up the C0 parameter for the CIM6 load model when initializing the load from the initial condition.
    • Transient Stability: When attempting to close in a synchronous generator during a transient stability run, an access violation was occurring. The problem was the synchronous machine should not be allowed to close in, so we have fixed to prevent this.
    • Transient Stability: Fixed error in passing the Pord signal from WT3E model to the WT3P model. Previously the WT3P model was always using Pelec as an input. This would only impact the results when the low voltage active power management was active such as when modeling faults very near the wind turbine terminal.
    • Transient Stability: Fixed error in the speed signal passed from the WT1T or WT3T model to the WT1P/WT3P pitch control (stabilizer). Previously we were passing the generator speed instead of the turbine speed. This would only impact turbines using the 2-mass model.
    • Transient Stability: The internally stored Bus field "Angle, No Shift" is always between +/-180 degrees. The Bus field "Angle" is then this value shifted by the reference angle. Because the original value "no shift" is shifted between +/- 180 degrees it only makes sense to the "shifted" value between +/- 180 degrees as well. It has been change to make this true.
    • Transient Stability: Fixed error with how svsmo1 and svsmo2 handle the control of discrete shunts.
    • Transient Stability: Fixed an event/log message generated by a LHVRT and LHFRT saying that a generator was being opened when the generator was already open. No error in simulation here, just invalid event/log message.