Software Patches

January 13, 2016

Features and Improvements

  • General: Added a field with generators called Number of Mvar Capability Curve Points.
  • Transient Stability: Added BRAKE Load Characteristic model to represent a braking resistor such as the Chief Joseph Braking resistor. This model has 5 input parameters (ZmwStart, ZmvarStart, ZmwStart, ZmvarStart, and Tinsert). When a load with this characteristic is Closed during a simulation, it will start as a constant nominal impedance represented by ZmwStart + jZmvarStart. It will than linearly change into a constant nominal impedance represented by ZmwEnd + jZmvarEnd over a time of Tinsert seconds. Tinsert seconds after the load is closed in, the model will automatically trip the load again. During validation, if the load record to which this stability model is assigned is inservice, a validation error will occur which prevents you from running transient stability. The expectation is that the braking resistor will be represented by an OPEN load which has zero MW and zero Mvar in the power flow case, however the actual MW and Mvar in the power flow case are ignored.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed an access violation that could occur when using the STAR option to automatically determine the star bus number of a three-winding transformer when loading an auxiliary file.
    • Auxiliary Files (SCRIPT and DATA Sections): When saving a complete case to auxiliary file, the PWCaseInformation object was being written with Label fields that caused an error when trying to reload the file. This object does not have labels so that bad fields have been removed when writing an aux file.
    • Distributed Computation: Fixed an issue that would prevent distributed computation from finishing if a thread fails causing distributed computation to consider a machine failed but there are other unfailed threads remaining for a given remote machine.
    • Oneline Diagrams: When browsing for the folder that contains the built-in geographic border files, append the appropriate symbol instead of /.
    • Transient Stability: Fixed bug in exporting from the transient stability toolbar when directory does not exist.
    • Transient Stability: Some corrections with checking H parameter for MOTOR1 machine model.