Software Patches

May 31, 2011

Features and Improvements

  • General: New script command SetScheduledVoltageForABus([bus identifier], voltage). This command sets the stored scheduled voltage, vsched, for a bus according to how this is defined in the EPC format. This value is not used by Simulator but is stored for purposes of writing out to an EPC file. The setpoint voltages for generators and switched shunts regulating the specified bus are also set to the new voltage. The regulation range for switched shunts are modified for the new setpoint voltage according to how this is defined in the EPC format: vband = (VHigh-Vlow)/2 with newVHigh = voltage + vband and newVLow = voltage - vband.
  • Oneline Diagrams: Store default filetype (number, name_kV linking, label linking, or AXD) to make it easier to open subsequent onelines using the same filetype.
  • PV and QV Curve (PVQV) Tool: Attempt to speed up the process of determining how much additional var support is necessary for the power flow solution to converge when a contingency will not solve in the base case. Now look for the solvable point by tracing the QV curve from the present base case voltage up to the maximum voltage instead of tracing from the present base case voltage down to the minimum voltage.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: When running iterated ATC methods, the option to dynamically add slack buses as topology changes has been disabled. This means that any generation or load that is disconnected from the main island will become de-energized. This prevents incorrect results during the iterated portion of the process if a contingency causes generation or load to be islanded. This also mimics what is done using linear calculations for contingencies that island generation or load.
    • Contingency Analysis: When using integrated topology processing, contingency blocks were not being included in determining which breakers should be preserved when using the option to preserve breakers. This could result in incorrect results because all breakers that needed to be opened were not available. This has been fixed.
    • General: Fixed bug that was preventing the special contingency options from being available (not grayed out) with Limit Monitoring Settings.
    • Oneline Diagrams: Fixed bug that would unlink an interface field from the appropriate interface when viewing the interface field dialog.
    • Power Flow Solution: Fixed bug associated with equivalencing lines that have the equivalent line ID and non-zero charging values.
    • Power Flow Solution: Fixed some errors with custom expressions and custom model expressions to properly identify an expression as not being valid if all variables in the expression are not assigned to valid fields. A blank result for an expression means that the expression is not valid.
    • Simulator Automation Server (SimAuto): Fixed bug that would not allow matrix results for multiple direction PTDFs, matrix LODFs, and multiple TLRs to be returned from SimAuto functions.
    • Transient Stability: Prevent user from closing Transient Stability dialog while the analysis is running.