Software Patches

December 23, 2016

Features and Improvements

  • Contingency Analysis Tool: Added the ability for a CustomMonitor to be used during a contingency analysis solution process. If the monitor evaluates such that a violation would be recorded then the device can be instructed to be tripped. Additional features are built into the CustomMonitor object.
  • Power Flow Solution: Modified Simulator's check for performing Angle Smoothing when closing in a series of branches. If more than 5 sets of series-connected branches are found at the same time, then we will no longer perform angle smoothing. This avoids situations where appending cases together results in a large number of new closed in branches at the same time. Using angle smoothing in these situations is not helpful.
  • Transient Stability: Modified the ATRRelay to add a new parameter for the model at the end called “GenNum”. The default value will be 1. Valuse of either 2, 3, or 4 will switch which generators are called “1, 2, 3 and 4”. Normally the unit to which the ATRRelay model is assigned is always considered "Gen 1". By setting the GenNum parameter to 2, 3, or 4, the generator to which the ATRRelay is assigned is considered the be "GenNum" instead. The original “GenNum” generator will then become Gen 1.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): For some fields, entering a blank input should not be allowed. Within the case information displays these blank entries have always been ignored. However, when loading an AUX file it was found that in some situations we were allowing this entry when it should not have been allowed. Two examples were the name of a bus (shouldn't be blank), and the status of a branch (blank was being interpreted as setting the branch to OPEN). This has been fixed.
    • Auxiliary Files (SCRIPT and DATA Sections): When writing out the Network Model for the Auxiliary File Export Format Description we were writing out Switched Shunts without some needed fields. This has been fixed.
    • Auxiliary Files (SCRIPT and DATA Sections): Added AutoControl field to the Network Model Auxiliary File Export Format Description
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed an issue when reading Shunt records that represented SVCs. This could lead to the solution failing on the initial solution attempt after loading the AUX file to create the SVC. Hitting solve a second time would result in a valid solution. With this fix it will solve immediately.
    • File Formats: There were bugs with writing out the RAW Transformer records when using the CW = 2 and CW = 3 flags. These have been fixed.
    • File Formats: Fixed reading of the series X value when using the CZ=3 on in a RAW file
    • File Formats: Fixed reading the mimimum and maximum phase shift when there was a fixed tap ratio on the secondary side of a 2-winding transformer. The minimum and maximum phase shift was being scaled by the fixed tap was was incorrect.
    • File Formats: Fixed error when reading the secondary winding maximum and minimum tap ratio when using the CW=2 or CW=3 flag. The tap was being scaled by the incorrect voltage. Typically there are not control features on the secondary and tertiary windings so this had not been noticed before.
    • File Formats: Modified to write all branch and transformer impedance and admittances using scientfic notation with 6 significant digits to avoid problems with not having enough decimal places in the file.
    • File Formats: When writing out tap ratios on using CW=2 flag, made sure that for low voltage (below 1.00 kV we were writing out enough decimal places so that we did not loose numerical precision)
    • File Formats: Previously, Simulator would not write out to a RAW file a series resistance smaller than 0.000005 or series reactance smaller than 0.00001. Values smaller than this were written as zero. This is no longer done when writing to RAW files.
    • File Formats: When writing out the magnetizing B and G when using CM=2, we were not writing out the value properly.
    • Transient Stability: Added the ability to read bus and branch measurements object from a dyr file reading the user defined model REPCAU1.
    • User Interface Dialogs: Added more decimal places when showing nominal kV on the Transformer Base dialog