Simulator 22 Patches

New Features

Bug Fixes

Date

September 10, 2021

Bug Fixes

  • Optimal Power Flow (OPF): In very rare situations for Interface definitions that contain many BRANCHOPEN InterfaceElements that result in the complete isolation of parts of the power system the calculation of the interface flow could become inaccurate. This could mess up calculations such as an OPF solution which uses the Interface MW flow to calculate the OPF solution. Internally, a numerical summation of very large values is done and that calculation was incorrectly using single-precision floats (7 significant digits). A user encountered an example where the equivalent of the subtraction of (123456789 - 123456789) was not returning 0.0 but instead what appeared to be random 2 digit number. This has been fixed by using double-precision instead to maintain enough significant digits to prevent this bug.
  • Transient Stability: Fixed the option on the Transient Stability dialog when processing multiple contingencies to choose whether to show results by a single contingency or multiple contingencies on the Results from RAM tabs.

September 8, 2021

Bug Fixes

  • Oneline Diagrams: Left-clicking and dragging on top of a background line when in Run Mode should simply pan the oneline in the direction of the dragging. This worked for most background lines, but not if the background line had been created by loading from a Shapefile. This has been fixed.

September 7, 2021

Bug Fixes

  • GIC: Fixed some errors with trying to get results for a transient stability run of the transformer GIC.
  • Transient Stability: Fixed some errors in VHVDC1 implementation.

September 3, 2021

Features and Improvements

  • Transient Stability: Adding new REPC_C plant controller model for testing
  • Bug Fixes

    • File Formats: Changes made in August 20, 2021 patch for storing information read from an EPC file regarding VSC DC Line objects caused a bug with saving out a PWB after loading a RAW file for a case that includes a VSC DC Line. This has been fixed.

September 2, 2021

Bug Fixes

  • Transient Stability: Fixed a bug where distributed results were not being saved to hard drive.
  • Transient Stability: When creating an open transient contingency action for a branch, the One Phase Open option will no longer appear on the GUI dialog. This option has not been implemented and an action defined as this would act the same as an Open Both action.

August 31, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command LineLoadingReplicatorCalculate with the syntax
    LineLoadingReplicatorCalculate([Branch 1 2 1], [InjectionGroup ig1], Yes, 50.0, NO, DC);
    LineLoadingReplicatorCalculate([Branch 1 2 1], [InjectionGroup ig1], Yes, 50.0, NO, DC, No, 0.5, 2);
    The parameters are
    1. Identifying string for the branch
    2. Identifying string for the injection group
    3. YES or NO for whether to only include AGC=YES devices
    4. Number representing the desired MW flow on the Branch
    5. YES or NO for whether to implement the changes after performing the calculation
    6. DC, AC, or DCPS for the linear solution method to use to perform calculation
    7. Optional, YES means to use the fields MWMax and MWMin for limits on load changes. NO means to use a multiples of the existing load for the minimum and maximum, with the multiplies as next 2 parameters
    8. Optional, If parameter 7 is NO, then this is the multiple of the existing load to use a minimum value (should be less than 1.00)
    9. Optional, If parameter 7 is NO, then this is the multiple of the existing load to use a maximum value (should be greater than 1.00)
  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command LineLoadingReplicatorImplement. This command has no parameters. The command will implement the control changes found by the LineLoadingReplicatorCalculate() command, so it is important to run that command before this.
  • File Formats: Added ability to store values read from EPC file for a 2-terminal DC line for values not used in power flow solution:
    Rectifier Gamma Min, Rectifier Gamma Max, Inverter Alpha Min, and Inverter Alpha Max. While these values are not used with the power flow solution, the value Inverter Alpha Min is used in the recently added CHVDC2 model. That value is not included in the DYD record for the CHVDC2 model, so we must carry it around with power flow data to properly read EPC/DYD file pairs.
  • Bug Fixes

    • Oneline Diagrams: Fixed how substation display objects use Default Drawing Values to highlight voltage limits. If showing the "Min kV of Highest Nom kV" or "Min PU of Highest Nom kV" fields within a substation display object, the color of this text will be the Limit Highlight Color specified with the Default Drawing Values if at least one bus in the substation is outside its voltage limits. If there is dynamic formatting in effect the dynamic formatting color will be used instead. The Limit Highlighting Used field was being ignored, but it is now being used to determine if the Limit Highlight Color should be used. The default color for the substation text will be used when the Limit Highlight Color is not used and in the absence of any dynamic formatting.
    • Power Flow Solution: Fixed bug that could prevent the DC converter equations from solving to a solution very close to the minimum firing angle at the rectifier. The solution may instead setting a transformer step 1 stepsize away a solution near the mimimum firing angle.
    • Transient Stability: Cleaned up the network boundary equation for the converters of a VSCDCT VSCDCLine dynamic model.
    • Transient Stability: Modified the bad input data treatment when the branch P, Q, or I measurement are needed for an REPC_A model but a branch is not specified. Previously we just assumed all flow measurements were 0.0, but this has been changed so that in this situation we use the output of the generator instead.
    • Transient Stability: Fixed a bug with Result Analyzer that was giving the wrong data value in some data points if the results were loaded from Hard Drive. For example a field that is scaled by SBase.

August 27, 2021

Bug Fixes

  • Transient Stability: Modifying how blocking is treated in the VHVDC1 voltage source converter DC line model. Also cleaned up the network interface equations for the VHVDC1 VSC DC Line dynamic model
  • Transient Stability: Fixed a bug where plots from a Distributed TS run were not being generated correctly when other results were not being stored

August 25, 2021

Features and Improvements

  • Case Information Displays: Updated description for the Int MW field for areas, zones, etc. to better reflect how it is calculated.
  • Oneline Diagrams: Improved the handling of Case Information Memo oneline fields.
  • Transient Stability: Added ability to load the VHVDC1U user-written model from a DYR file and load it into a VHVDC1 model in PowerWorld. This is a voltage-source converter DC line model (VSCDCLine)
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When interpreting interface elements for loads using a single string meant to represent the label of the load, it was possible for it to mis-identify the load if the user was using a label for a load that was exactly the same as either a bus number or "name_kv" of a bus in the system and that bus had a load. This has been fixed.

August 24, 2021

Bug Fixes

  • File Formats: Fixed access violation that was introduced in previous patch on 8/20/21 which would occur when loading a RAW file with a DC line record. Bug only existed in 8/20/21 patch.

August 20, 2021

Features and Improvements

  • File Formats: Added ability to read "vs converter data" from EPC files and then parse the records to create 2-terminal VSC DC Line objects. Also added the ability write the "vs converter data", "dc bus data", "dc line data" to an EPC file.
  • Oneline Diagrams: Added a new feature called a Spatial View which can be used for temporarily laying out a part of the system using geography if available. Intent is for this feature to work like a temporary Bus View, though you will also be able to save the spatial view as a stand-alone oneline after building it.
  • Power Flow Solution: Added 2 new options to modify the algebraic equations used to model line-commutated DC converters. Both options are not recommended, but when reading an EPC file PowerWorld will set these 2 options to YES so that the DC converter solutions will match the equations used by PSLF.

    Use Approximate DC Converter Power Factor Equations:
    Sim_Solution_Options VariableName = UsePSLFConverterApproximatePowerFactor
    Set to YES to use an approximate calculation (to match what PSLF does) for DC converter power factor of
    cos(Phi) = 1/2*(cos(FiringAngle) + cos(FiringAngle + mu))
    instead of the more accurate equation
    tan(Phi) = (2*mu + sin(2*FiringAngle) - sin(2*(mu + FiringAngle)))
    /(cos(2*FiringAngle) - cos(2*(mu + FiringAngle)))

    Use PSLF treatment of Fixed Tap in DC Converters:
    Sim_Solution_Options VariableName = UsePSLFConverterIncorrectFixedTap
    This only impacts DC converter transformer equations.
    NO - Uses the correct equation of TotalTap = VariableTap + FixedTap - 1
    YES- Uses the incorrect equation of TotalTap = VariableTap*FixedTap (implemented by PSLF).
  • Transient Stability: Added ability to read from a DYD file VHVDC1 models for 2-terminal VSCDCLine records.
  • Bug Fixes

    • Transient Stability: Bug fix for generating plots of fields only if they are stored in Hard Drive (storing to RAM is okay). Users might have observed that incorrect values were being plotting fields of certain devices. For example, plotting the "OEL Other 1" field for a Generator which does not actually have an OEL Active. The correct behavior is to not show any plot series on the generated plot, because the field itself does not exist for that generator. This issue is now fixed.

August 18, 2021

Features and Improvements

  • Available Transfer Capability (ATC) Tool: For the TransferLimiter object type, the variables for ATC_ExtraMonitor and ATC_ExtraMonitorSens can now be identified by the object identifier for the object they are monitoring instead of the location number. Example: ATCExtraMonitor:"Branch '1' '2' '1'".
  • Bug Fixes

    • File Formats: Fixed a bug where when reading an EPC file with multiple Shunt sections, we would only process the shunts in the last section read, and the previous sections of shunts would be lost.
    • Oneline Diagrams: After the file save is complete when using the ExportOneline script command, the oneline will now be returned to the options and view that were in place prior to issuing the command.
    • Transient Stability: Any OEL connected to Exciter ESST4B now has the ability to automatically modify the VOEL output so that initial limit violation can be prevented when the "Modify Limits" option is chosen in Transient Stability options. This modification will only occur if an OEL can initialize to Activation Status = Idle.
    • Transient Stability: When Qref=0 for OEL4C, internally the program sets Qref to current Qmax from the power flow records. This was already being done. However, for generators that have an internal step up transformer, Qmax needed to be transformed to the generator terminal-side. This modification has now been made.
    • Transient Stability: Fixed the Exciters EXAC1, EXAC1A, EXAC2, EXAC8B and REXS to work properly when the Hard Limit is implemented with the OEL1 Over excitation model. Previously the EFd limits were calculated without taking into effect of the function Fex in the output of the Exciter.

August 16, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): For ATCWriteToText script command, messages will appear in the log if any invalid field variable names are specified.
  • Available Transfer Capability (ATC) Tool: Added new option for handling branch and interface limit violations in the PV tool. There is now an option called "Stop in Base Case Only" that can be applied to either type of violation. When this is used, only base case limit violations can cause a scenario to be critical. Any limit violations that occur for contingency scenarios will be ignored.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When loading a Custom Monitor from an auxiliary file or pasting from Excel and the Object Name is not specified as blank and cannot be found, set the Enabled field to NO so this custom monitor is ignored. When the Object Name is blank this means that all objects of the specified type will be monitored. Do not want all objects monitored by default if the particular object cannot be found.
    • Transient Stability: Fixed a bug when the loads do not have a distributed generation model but do have distributed generation load defined with the load and the total load was negative. It was causing some transient solution problems. Also a warning will be presented when the distribution generation do not have a transient model but have distributed generation with the load.
    • Transient Stability: Fixed a bug with the Result Analyzer Time Window dialog. When setting the Maximum number of violations to store, if a number greater than a 100 was set with the dialog, the value was set to a 100. In the Result Analyzer time window table the maximum number of violation to store was working fine.

August 9, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command named RotateBusAngleInIsland. The first parameter is the identifying information for a bus between square brackets and the second parameter is a numeric value for a new angle. The script command will rotate all the angles in the island to which the bus belongs by the same shift such that the specified bus ends up with a bus angle specified by the second parameter.
    RotateBusAnglesInIsland([BUS num], Value);
  • Case Information Displays: Added a right-click option on a case information display of buses to "Rotate Bus Angles in Island". You then choose what angle you would like at the bus you have chosen and then all angles in the island to which this bus belongs are rotated by the same angle to achieve the desired angle at the chosen bus.
  • Case Information Displays: Added fields to branches in Neighbors\Parallel Branches with Flipped Terminals to indicate if there are parallel branches with flipped terminals. This could indicate a modeling error, particularly for transformers.
  • Transient Stability: In VHVDC1 the Pacref is treated as equal to 0.0 when either converter is blocked. This modification also changes it so that Idcref is also treated as 0.0 when either converter is blocked. This only mattered when using the dPmax and dPmin values to enforce a rate limit on the change in Pacref.
  • Transient Stability: Added the signals 'Iact', 'Ibias', 'Terr', 'IERRinv1' and 'IERRinv2' for the OEL2C model Other Fields.
  • User Interface Dialogs: Added button to the Edit Mode Branch dialog to allow the easy flipping of the from and to buses.
  • Bug Fixes

    • File Formats: Fixed an access violation that could occur when during saving/loading primary contingency records.
    • File Formats: Fixed access violation that would occur when loading an EPC file which contained no Shunt record section.
    • Transient Stability: More robust initialization for OEL2C.
    • Transient Stability: When an OEL model was getting VFE from generators as an input it was not getting the VFE correctly.
    • User Interface Dialogs: Fixed bug when entering the branch Length on the Branch Options dialog while in edit mode. The edit box was being updated with a conversion to the selected miles or km unit while typing a new value making it impossible to enter the desired value.

July 30, 2021

Features and Improvements

  • File Formats: Adding features to load RAW Version 35 files

July 29, 2021

Bug Fixes

  • GIC: On GIC, Time Varying Electric Fields added error message is someone tries to load an upsupported file type. Previously this was causing an exception error.
  • Transient Stability: Fixed a bug in where the Result Analyzer wasn't working when needed to load results from Hard Drive. Now it loads results from hard drive and also works to load some results from RAM and Hard Drive at the same time.
  • User Interface Dialogs: Fixed a bug with the Generator Display dialog in Edit Mode when modifying the Voltage Tolerance it was setting the Voltage Setpoint to the Voltage Tolerance when you close the dialog or hit the Save button.

July 23, 2021

Features and Improvements

  • File Formats: Fixed a bug with the MBL in the WECC switch file that wasn't creating the transient contingency. Now it will create the MBL transient contingency.

July 22, 2021

Features and Improvements

  • General: On the Tools, Connections, Determine Shortest Path Between
    1) added a tab that shows the lines that are in the path
    2) corrected the order in which the buses are shown to start at the start bus and go to the end bus, 3) on the list displays for the buses, substations, areas and zones added a local menu entry to get access to this form. Because the Buses list display already had local menu entry to another form for showing the shortest path it now has two options with the original (older) approach labeled as old. A difference with the older approach is it did include DC lines show some folks might prefer that. This old form also now shows lines.
  • Transient Stability: Changed the transient stability so when a generator is closed by default its MW setpoint is not set to zero. However the generator is taken off of AGC control.
  • Bug Fixes

    • Transient Stability: Changes associated with closing a generator in transient stability. Now they work correctly when closed at off-nominal speed. Also, AGC control is disabled when a generator is reclosed.
    • Transient Stability: Cleaning up captions for transient events when specifying to close generators.
    • Transient Stability: Fixed a bug where TS plots in a Distributed run were showing up blank if other results were not saved.
    • Transient Stability: Fixed a bug with the OEL2C that was creating an initialization problem for the exciters derivatives because it was setting the OEL output to the incorrect initial value.
    • User Interface Dialogs: Fixed errors on the Direction dialog

July 16, 2021

Features and Improvements

  • Oneline Diagrams: When auto inserting buses or substations on a oneline diagram based on geographic coordinates stored with data records and the coordinates are not valid, messages will now appear in the log indicating that objects could not be added to the oneline.
  • Transient Stability: Changed the defaults for the TTSGenOther_AGCControlModel_BASE to all zeros to emphasize by default they are automatically set.
  • Transient Stability: Improved network convergence when CHVDC2 model uses the commutation failure features.
  • Transient Stability: Added ability to feed in the auxiliary current signal into the CHVDC2 model

July 15, 2021

Features and Improvements

  • User Interface Dialogs: On BusesShortestPath added showing the lines. This can then be used with GDV displays.
  • User Interface Dialogs: Removed the Close button on the Keyboard Shortcuts dialog because it didn't do anything. The X to close the dialog does everything that needs to be handled before the dialog is closed.
  • Bug Fixes

    • General: Improved performance when deleting GICXFormers.
    • General: Fixed an issue where downgrading from a later patch release to an earlier patch release would break the Simulator installation causing the main executable to not be replaced by the earlier version executable.
    • Transient Stability: Temporary disabling the Result Analyzer when using the State Manual Control tool button pressing of One Time Step or Until a Specific Time. You can do it after the simulation stops is just that the default is to check for the Analyze Time Window option and if it is checked then it will do it right after the simulation stops and sometimes we do not have enough points and create access violations and other issues.
    • User Interface Dialogs: New features from July 7 for directly specifying a Custom Detail were not working properly and caused the CustomDetail dialog to appear when opening the oneline display options dialog. This has been fixed.

July 9, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added LoadAXDFromAXD("filename", CreateIfNotFound) script command that will allow a display auxiliary file (AXD) to be loaded via this script command that is part of another display auxiliary file (AXD).
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug that when the the script command was using a space in the string for a file type it was causing an error in the script command. Now if the user put a space in the file type of the script command it will not cause an error for the script.
    • Available Transfer Capability (ATC) Tool: When doing an ATC calculation, a contingency that completely isolates either the buyer or seller will be ignored by the ATC calculation.

July 8, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): FixFlowArrowLineEnds and FixFlowArrowPosition script commands now have both input parameters as optional. When the Oneline name is not specified the script commands will be applied to the oneline for which the AXD file was applied. When the LayerName is not specified any flow arrow objects in any layer will be modified.
  • Bug Fixes

    • Transient Stability: For stability added an offset field to the Area AGC to that all the area agc dispatch does not occur at the same time. Ideally this field is a random value that is between -0.5 and +0.5 of the update time.
    • Transient Stability: Fixed a bug that when loading Advanced Options in Transient Stability plots, if the chart have more than one subplot it was causing an error. That error was fixed and the advanced options are loaded for the entire chart.

July 7, 2021

Features and Improvements

  • Available Transfer Capability (ATC) Tool: Added script command ATCWriteScenarioLog("filename", AppendFile, filter) that will write the detailed log information for ATC Multiple Scenarios.
  • General: When a case has been modified a prompt to save the case will appear by default if opening another case, open a new blank case, or closing Simulator. If this happens while the contingency dialog is open and the system state is not in the contingency reference state, another prompt appears asking if the contingency state should be saved. There is now an option to Cancel so that the original action that led to the prompt will be abandoned and allow the case to be saved as the modified base case and not the contingency state.
  • General: Added an option on the Simulator Options Environment page to "Prompt for saving modified case." This is checked by default. This is only stored in the registry and does not have auxiliary file support. When not checked the prompt for saving a modified case when opening a new case, opening a new blank case, or closing Simulator will not appear.
  • User Interface Dialogs: Added ability to access saved custom Display Detail levels both through the Options ribbon tab and through the local menu on onelines.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed an "ID collision" error that could occur when trying to move a three-winding transformer to different buses or change the ID.

July 1, 2021

Features and Improvements

  • Optimal Power Flow (OPF): Previously it was possible to attempt to solve the OPF/SCOPF with the Island-based AGC enabled. This should not have been allowed since it is using two different algorithms to dispatch the same generation. The code has been modified to present an error message 'Error: cannot solve OPF with Island-based AGC enabled.' when an OPF/SCOPF solution is attempted with Island-based AGC enabled.
  • Security Constrained OPF (SCOPF) Tool: Previously it was possible to attempt to solve the OPF/SCOPF with the Island-based AGC enabled. This should not have been allowed since it is using two different algorithms to dispatch the same generation. The code has been modified to present an error message 'Error: cannot solve OPF with Island-based AGC enabled.' when an OPF/SCOPF solution is attempted with Island-based AGC enabled.

June 30, 2021

Features and Improvements

  • Power Flow Solution: Added Message Log warning messages when a VSC DC Line is not properly configured to alert the user that the VSC DC Line is being ignored. As an example, if both converters are configured for MW control and error message will be generated that says "DCMode at From and To Converter are both the same. One side must be set to Power and the other to Voltage for the VSCDC Line to operate."
  • Security Constrained OPF (SCOPF) Tool: set hints for the SCOPF form options, and added longer descriptions for them
  • Bug Fixes

    • Contingency Analysis: Fixed bug properly displaying contingency injection sensitivity results in the Contingency Violations Display (LimitViol object type).
    • Distributed Computation: Fixed distributed computation computer verification so that when no machines are defined, verification no longer causes Simulator to freeze.
    • Optimal Power Flow (OPF): In some cases MWMarginalCostValues was not being saved as subdata when saving an AUX file
    • Power Flow Solution: If a generator had a negative MW output and it was using Boundary Power Factor control to set the Mvar limits, the Mvar limits would end up switched with the minimum being positive and the maximum being negative. This has been fixed.

June 28, 2021

Features and Improvements

  • Available Transfer Capability (ATC) Tool: When storing ATC Extra Monitor flow values in the base case for use when estimating extra monitor flows at various transfer levels when using the iterated ATC methods, an extra flow value will now be included when contingencies are being iterated on at the base case transfer level at which the contingency last solved.
  • Power Flow Solution: Added option to "Use Loss Factor For DC Line tielines". This will use the two-terminal DC line aLoss term to assign the metered point a fraction of the way along a two-terminal DC line. This term was always maintained previously but not used in the solution. This feature is supported in EPC files but not RAW files. PowerWorld Simulator now has a global option regarding whether to use this Loss Factor. When not using the Loss Factor (aLoss) we will default back to the MeteredEnd specification instead.

June 25, 2021

Features and Improvements

  • Case Information Displays: Exposed multi-section line ID field in the branch table under the Multi-Section Line folder with the name MS Line ID.
  • Bug Fixes

    • GIC: Modified so the GIC Analysis Form, Field/Voltage Input the Non-Uniform Input Field (usually a b3d) field is enterable with the result saved.
    • Transient Stability: When reporting total load for the entire case in transient stability when load models include a distribution equivalent, the totals were not correct. They were correct for individual loads, areas, zones, substations, etc... but not for the entire case. This has been fixed.
    • Transient Stability: Fixed an access violation when Saving Data from the Show/Save Selected Plot Data option in the Plot Designer. The error was happening when the plot included a PlayIn Signal. It was preventing the data from been saved. This error was fixed.

June 22, 2021

Features and Improvements

  • Contingency Analysis Tool: Added code to keep unlinked contingency elements when reading OTG contingency files. Previously unlinked contingency actions were discarded.
  • Oneline Diagrams: The Text Object dialog now has a format button to give direct access to the format dialog. This matches what has long been done with the line dialog.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: In ATC when using the (IL) then Full CTG solution method, corrected how a negative stepsize is handled when iterating on a failed contingency and the limiting element is overloaded at a step when the contingency does solve. When iterating on a failed contingency the stepsize is reduced by half if trying to find a transfer where the limiting element is not overloaded. This is incorrect if the stepsize is negative because the stepsize needs to become more negative to reduce the loading on the limiting element. The new stepsize is now (stepsize + stepsize/2) to make it more negative.
    • Available Transfer Capability (ATC) Tool: Fixed a couple of inconsistencies with the ATC solution when using the (IL) then Full CTG Solution.
      (1) When iterating on individual limiters with a contingency implemented, use the OTDF cutoff threshold instead of the PTDF cutoff threshold.
      (2) When iterating on individual limiters with a contingency and an infinite transfer level is reached during the step where the limiter is iterated on by linearly modeling the contingency, no longer continue to the step where the contingency is actually implemented. The result will report Iteratively Found as YES_INFINITE.
    • Contingency Analysis: Fixed infinite loop that might result when using Best Fit actions for contingencies and remedial actions.
    • Transient Stability: Fixed a divided by zero in HYG3 when (fRelec = 0) and (fRGate = 0).
    • Transient Stability: There was an access violation bug when no results are saved into RAM or Hard Drive but saving plots as a file. The problem is fixed.

June 17, 2021

Bug Fixes

  • Difference Case Tool: Fixed an access violation that would occur when saving present case topological differences over an entire model when some of those changes include new or changed three winding transformer star buses.
  • File Formats: When loading a FACTS device from a PTI RAW file which was translated to a switched shunt SVC with svsmo3 there was a divide by zero error occurring. This has been fixed.

June 15, 2021

Features and Improvements

  • Oneline Diagrams: Enhanced ability for finding objects on a oneline diagram
  • Bug Fixes

    • Case Information Displays: Fixed a bug with Limit Monitors when creating a limit monitor the user puts a bus pair limit greater than A, B, C pr D. It was creating an access violation. This is now fixed.

June 11, 2021

Bug Fixes

  • Oneline Diagrams: Added error message to InsertConnectedBusesAction when trying to insert buses connected to a display bus based on it being linked to the specified data Bus object if no display objects can be found. This is not considered a fatal error.

June 10, 2021

Bug Fixes

  • Oneline Diagrams: In the AutoInsertBorders_Options object more than one border file can be specified to be applied at one time. This would not work if the specified borders included spaces before or after the comma delimiter. This has been fixed.
  • Oneline Diagrams: Fixed access violation that could occur when auto inserting interfaces on a oneline diagram.
  • Transient Stability: Fixed an access violation that happens when the transient simulation is aborted because of limit monitors and there are not enough points to do the result analyzer modal analysis. Now it will not have the access violation and the modal analysis will not be done.
  • Transient Stability: When auto-inserting transient contingencies the multiple contingency grid was not refreshing and showing the new inserted contingencies. You needed to get out of the multiple contingency option and return back in order for the grid to refresh. That was fixed and now will refresh after auto-inserting contingencies.

June 9, 2021

Features and Improvements

  • Case Information Displays: Fixed bug that was making the Bus Fields LoadNetMW and NetMW conflict with one another resulting in the NetMW field (showing the net injection at the bus) to not work properly. (Same fix for LoadNetMvar and NetMvar).
  • Bug Fixes

    • Optimal Power Flow (OPF): Fixed OPF initialization problem.
    • Security Constrained OPF (SCOPF) Tool: Included two additional SCOPF options when saving the options to an AUX file: "Set Solution as Contingency Analysis Reference Case" and "Basecase Solution Method"
    • User Interface Dialogs: The Close and Help buttons on the SCOPF dialog would move to the right when increasing the size of the dialog. This has been fixed.

June 7, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added AXD file support of GeoDataViewSummaryObjects and SummaryLineObjects.
  • Bug Fixes

    • Transient Stability: Added code for Critical Clearing time to work with result window analyzer and eliminated the messages from appearing when running the analysis in other than the result analyzer gui.

June 4, 2021

Features and Improvements

  • Power Flow Solution: Continued improvements with handling switched shunt ranges voltage setpoints that may conflict with generator setpoints.
  • Bug Fixes

    • Oneline Diagrams: When showing the oneline option to show out-of-service elements as dashed lines, the symbols for a transformer and series cap/reactors were not showing as dashed. The line segments up until the symbol were dashed, but not the symbol. This has been fixed so that the symbol also appears as dashed.
    • Security Constrained OPF (SCOPF) Tool: Included two additional SCOPF options when saving the options to an AUX file: "Set Solution as Contingency Analysis Reference Case" and "Basecase Solution Method"
    • Transient Stability: Added exciter ESST1A_GE to be able to set a Hard Limit with the over excitation OEL1.
    • Transient Stability: UEL2C now allows parameter KUI = 0
    • User Interface Dialogs: Fixed a bug with the Switched Shunts dialog that when the shunt is an svsmo3 was showing the current pu values multiplied by the Sbase for the Continuous Range and the Switching Range. Now it will show the values in pu value of the current. A better caption was inserted for making explicitly that the Continuous Range and the Switching Range is in pu of the current.

June 2, 2021

Bug Fixes

  • File Formats: ZBR Threshold value used when determining regulated buses for generators, switched shunts, and transformers was not being saved to PWB files. This has been fixed.
  • General: Added more error checking when copying and pasting so that errors don't result in access violations.
  • Oneline Diagrams: When showing the oneline option to show out-of-service elements as dashed lines, the symbols for a transformer and series cap/reactors were not showing as dashed. The line segments up until the symbol were dashed, but not the symbol. This has been fixed so that the symbol also appears as dashed.
  • Power Flow Solution: ZBR Threshold value used when determining regulated buses for generators, switched shunts, and transformers was not being saved to PWB files. This has been fixed.
  • User Interface Dialogs: When using an SVC type svsmo3 the Switching parameters are in Amps. We were using them in Amps in our code but the dialog was displaying the Switching parameters as Mvar. Now it shows Amps in the dialog for the switching parameter.

June 1, 2021

Features and Improvements

  • Transient Stability: modified treatment of D term for the new MOTORC to be the exponent for mechanical power.
  • Transient Stability: Added ability to read/write the ESAC8C model from a DYD record.
  • Bug Fixes

    • Case Information Displays: Fixed fields displaying improperly when in base case or difference display mode.
    • Case Information Displays: Fixed access violation that could occur when loading auxiliary file with DataGrid section that contains an empty ColumnContourInfo subdata section.
    • Contingency Analysis: Bug fix for access violation during saving a case with contingency results and then deleting a transmission line. This would happen if one of the terminal buses was referenced in the Contingency Elements as a Bus open or close.
    • Distributed Computation: Fixed an issue where distributed transient stability didn't return result analysis violations. This is now fixed.

May 27, 2021

Features and Improvements

  • Transient Stability: Added a new load model named MOTORC which is a combination of the INDMOT1P with the same contactor, under-voltage, and thermal relays added as used in LD1PAC.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: Transfer Limiter case information displays for specific types of limiters were not displaying the correct column headers when viewing Normal headers. This has been fixed.
    • Contingency Analysis: Fixed access violation that would occur when saving primary contingencies without any results. The code was attempting to access the results without first initializing them.

May 26, 2021

Features and Improvements

  • Contingency Analysis Tool: Modified the Best Fit Open contingency and RAS actions for Interfaces and Injection Groups. The algorithm attempts to find the smallest number of devices that can meet the desired amount. The more devices there are to consider the more time it takes to determine all of the possible combinations. If there are more than 20 devices, the devices will be sorted from high to low impact and examined in blocks of 20. If the entire 20 devices are needed to meet the desired amount all will be opened and then next block of 20 devices will be used to meet the remaining amount. This process continues until it is not required that a set of 20 devices are all required to meet the remaining amount. This block will use the combination algorithm to fine tune which devices are opened.
  • Transient Stability: Internal modifications to the LD1PAC model to split up the features of the under voltage, contactor, and thermal relays into pieces so that these can be applied to other load models
  • Transient Stability: modified SVSMO3 so that values of Kdbd < 1.0 are treated as Kdbd = 1.0

May 25, 2021

Features and Improvements

  • Available Transfer Capability (ATC) Tool: With iterated ATC methods added two new Iteratively Found strings: YES_INFINITE and FULL_INFINITE. These indicate that the PTDF/OTDF have become too small in the process of iterating on an individual limiter, and the transfer limit is treated as infinite. This had previously been indicated by the Trans Lim value being set to a very large number, and now these new strings give another clearer indication of this. Additionally, the highlight color for these types of limiters are lighter versions of yellow and blue used to indicate YES and FULL limiters, respectively.
  • Contingency Analysis Tool: Added script command CTGVerifyIteratedLinearActions that takes a single parameter, filename, for an input. This action will save a file that identifies which fields and conditional actions (remedial actions) are valid for use with the iterated linear analysis method for contingency and ATC analysis.
  • Transient Stability: For some exciters added checking when E1=E2 and SE1 <> SE2 <> 0.
  • Bug Fixes

    • Distributed Computation: When running distributed contingency analysis the Selected field for Contingency objects was being set to NO after the run. This has been fixed.

May 24, 2021

Features and Improvements

  • GIC: Updated GIC code to better handle intermediate buses of multi-section lines. If the intermediate bus does not have any latitude/longitude specified then we will estimate the location using branch resistance values.
  • User Interface Dialogs: Updating the multi-section line dialog. There is now a regular listing of the buses in the object.
  • Bug Fixes

    • Contingency Analysis: When saving a PWB file and the contingency analysis dialog was open, the options as set on the dialog were not always being saved to the PWB file. This has been fixed.
    • File Formats: When reading an EPC file and SVCs are allowed to control fixed shunts the linking to the fixed shunts was not being done correctly. This has been fixed.
    • Oneline Diagrams: Fixed a bug where the Snap To Grid setting was continually being reset to True
    • Power Flow Solution: When multiple lines that are not in series are closed and they have common bus terminals, angle smoothing does not work correctly. When this situation is encountered voltage estimates will be done instead on the buses that are involved in the line closures

May 19, 2021

Features and Improvements

  • User Interface Dialogs: Updated the Multi-Section Lines dialog to include geography and GIC field support. Also added buttons on the Branch dialog to provide access to the Multi-Section Line dialog. Also also added fields to a branch to show if there are in-service or bypassed series capacitors on lines.
  • Bug Fixes

    • File Formats: Corrected some fields written for SVD devices in the EPC format export.
    • Oneline Diagrams: Fixed a bug where some display elements were not properly linking to their intended anchors when loading a PWD file
    • Transient Stability: Fixed error in how the short-term Rating Curve is applied to the SVSMO3 model. This was not allowing the SVSMO3 to supply a current a multiple of Ishrt higher for a short period of time when configured to do so.

May 18, 2021

Features and Improvements

  • Transient Stability: Modified how network boundary equation solution is handled when bypassing a DC line using the CHVDC2 model. It now ensures that an extra solution occurs and bus frequency calculation is updated to prevent strange bus frequency calculation spikes when bypassing and unbypassing.

May 14, 2021

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): SaveData script command will now produce an warning message if an empty fieldlist is specified.
  • Available Transfer Capability (ATC) Tool: Fixed access violation bug when deleting transfer directions from multiple direction ATC analysis. This only happened after ATC analysis had been run (i.e., transfer limiter results were present).

May 13, 2021

Features and Improvements

  • Case Information Displays: Added new summary information for the summation of Load Dist MW Max, Load Dist MW Min, Load Net MW, and Load New Mvar for the following aggregations: Bus, Area, Zone, Substation, Owner, InjectionGroup. Previously you could only get information about the Min/Max and Net values for loads by looking at individual load records or by creating your own calculated field.
  • Bug Fixes

    • Distributed Computation: Fixed an issue in distributed contingency analysis where contingency violation injection sensitivities may be dropped when the controlling Simulator program is running on a computer under high load.
    • Distributed Computation: Added the ability to gather worst overload data over all contingencies for all branches when running distributed contingency analysis. Previously this data was only available through non-distributed contingency analysis.
    • File Formats: Bug fix for RAW file reading. Angle value was not being set correctly for node data read from a "SUBSTATION NODE DATA" section.
    • Transient Stability: Modification to help with numerical integration of the INDMOT1P and INDMOT1P_PTR load models

May 11, 2021

Features and Improvements

  • Case Information Displays: When creating a new Case Comment through script or aux file, a blank Time can be specified. Time is used as a key field so the current time will be increased in second increments until a unique time is found when loading multiple comments at the same time.
  • Bug Fixes

    • Transient Stability: In PowerWorld parameters T1, T2, T3 and T4 are in seconds in DISTRELAY and DISTRELAYITR but in DYD files those parameters are in cycles in DISTREL. These paraemters are now properly converted accordingly when reading and writing those parameters from the DYD format
    • Transient Stability: Exciters DC4B, ESDC4B and DC4C modification of Max limits at initialization.

May 10, 2021

Features and Improvements

  • Transient Stability: Modified so that if the State Pitch (output) of WTGPT_B is stuck at a non-windup limit, then if the PitchControl state has a derivative pushing the output further against its limit the PitchControl state derivative will also be set to 0.
  • Transient Stability: Modified so that if the State Pitch (output) of WTGPT_B is stuck at a non-windup limit, then if the PitchComp state has a derivative pushing the output further against its limit the PitchComp state derivative will also be set to 0
  • Transient Stability: Modified the REEC_D electrical control model so that when it goes into a blocking mode it instantaneously forces the currents at the network boundary equations of the generator to go to zero.
  • Transient Stability: Added a way to store DYD extra records in the pwb. Records like for a vscdc line or a dcmt model can be read. The strings can be saved with the pwb case and the user can see the string in a case info table and can delete them if desired. Then you can save the dyd file and those extra records will be also in the file.
  • Transient Stability: On the Modal Analysis Form there is now an option to Always Reload Signals from Source. If checked then the modal analysis signals are always reloaded from the source, as opposed to using the signals already in Modal Analysis. This option is most useful when the source is changing and the user would like Modal Analysis to always use the new source value. An example is when the source is the TS plots. This option is useful when the user is changing the TS and rerunning, and then looking at how the modal analysis results have changed.
  • Bug Fixes

    • File Formats: Removed old process that would update BranchDeviceType for a branch based on entries in CustomString:0, CustomString:1, or CustomString:2 after loading any aux file with branch data or using a SetData command on branch data. (This dated from 2006 and should have been removed years ago)
    • File Formats: Fixed failed power flow solutions that might occur when opening an EPC file while in edit mode.
    • GIC: Bug fix for reading PSLF *.GMD supplemental data file for (i) rdcsw/common parameter of 2 winding transformer, and (ii) kfactor for 3 winding transformer.

May 3, 2021

Features and Improvements

  • Transient Stability: Added the ability to read and write ESST5C model to a dyd file.
  • Transient Stability: Added the ability to read and write ESST6C model to a dyd file.
  • Transient Stability: Added stator frequency dependence on the CIM5_PTR model
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): In the SendToExcel script command the ClearExisting parameter was not being read correctly if enclosed in double quotes. This has been fixed.
    • Contingency Analysis: When using transient stability models with power flow contingency analysis no changes should be attempted if the device or the device's bus is disconnected. Not checking the bus connection status could cause excessive POSTCHECK loops. This has been fixed.

April 30, 2021

Features and Improvements

  • General: Made modification to load ID assignment when merging buses. Previously the next unused ID was used even when the default was available. Now the default ID will be used if there is not already a load at the bus using the ID. This is consistent with how other objects like generators work.
  • Transient Stability: Added a new dynamic phasor model of a single-phase induction motor model named INDMOT1P
    https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20INDMOT1P.htm
  • Transient Stability: Added a new motor model named INDMOT1P_PTR which is a simplified version of INDMOT1P, but includes the concept of progressive tripping and reconnecting
    https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20INDMOT1P_PTR.htm
  • Transient Stability: Added a new motor model named CIM5_PTR which is the same as CIM5, but includes the concept of progressive tripping and reconnecting
    https://www.powerworld.com/WebHelp/Default.htm#TransientModels_HTML/Load%20Characteristic%20CIM5_PTR.htm
  • Bug Fixes

    • File Formats: Fixed a bug where Simulator will save a modified case to an incorrect location when opening a different case. Simulator would save the case to the same folder containing the newly opened case instead of the folder where the case was originally stored.
    • Transient Stability: Fixing reading, writing and setting MWCap from a dyd file for governors PIDGOV and WT4T.

April 29, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added column contour to the AUX format as a SUBDATA section on the DataGrid (string grid customization) object.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: When using iterated ATC methods the ramping is done relative to load and generator outputs in the base case so that generators will hit and back off limits consistently if transfer stepsizes change sign. When using injection groups as the source and sink it was possible that the ramping was being done relative to the total transfer already achieved rather than this base starting point. This could result in oscillatory behavior. This has been fixed.
    • Transient Stability: Fixed a bug in which the reading a dyd file a certain dc branch wasn't loading the dynamic ecpdc model. Now this is corrected and the epcdc model is read into transient stability.
    • Transient Stability: Fixed a bug with writing cmpldwg DGMBase parameter. When saving into dyd file and the load object DGMBase value is zero it was writing the load object DGMBase value as zero and not the transient model value.
    • Transient Stability: Corrected UEL model MNLEX2. The other fields: Activation Status and PQSig values were being output incorrectly.

April 27, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added support for a Selected field with QVCurve object type. Added support for the Bus Selected field for the bus associated with the QV scenario.
  • QV Curves: Added script command QVWriteCurves("filename", IncludeQuantitiesToTrack, filter, Append) that will save a comma-separated text file with the QV curve points. Set IncludeQuantitiesToTrack to YES to also include any Quantities to Track along with the curve QV curve points. Filter is applied to the QVCurve object type. Set Append to YES to append results to an existing file or NO to overwrite an existing file.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): The special keywords for @DATE and @TIME used with script commands were providing the opposite replacement. @DATE was giving the time and @TIME was giving the date. This has been fixed.
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed access violation that would occur with SendToExcel script command if Header_List was not defined.

April 23, 2021

Features and Improvements

  • QV Curves: When running QV analysis, saving Quantities to Track while the analysis is running is now optional. This can slow down the processing. There is now a button on the Output tab of the QV dialog that allows saving Quantities to Track after the run is complete. There are also options on the local menu of the Results > Listing case information display that allow saving QV curve points with and without quantities to track.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed writing out auxiliary files so that they honor non-US regional Windows settings (i.e. using commas or periods as the decimal separator).

April 20, 2021

Features and Improvements

  • File Formats: RAW file reading for version 34 is now more lenient and allows the use of whitespace as a field delimiter.
  • Transient Stability: Vfe is available for ESAC5A Exciter model.
  • Bug Fixes

    • Contingency Analysis: When loading a PTI CON file with contingency elements specified with WND for opening or closing a single winding of a three-winding transformer, the elements read after this entry could end up being incorrectly specified. This has been fixed.
    • Power Flow Solution: Fixed an access violation that would occur when loading a case with more than 8 buses in islands without generation attached to DC lines.
    • QV Curve Tool: When rerunning QV analysis delete all quantities to track even if not rerunning particular scenarios so that the values in the file will have consistent headers.
    • QV Curve Tool: QV results for Quantities to Track were not being stored in PWB files. This has been fixed.
    • QV Curve Tool: When rerunning QV analysis existing results should be overwritten when rerunning a scenario instead of creating multiple results for the same scenario. This has been fixed.
    • Transient Stability: Changed default parameters for VHVDC1 so that Iqmin2 and Iqmin3 are both negative values (as these should almost always be negative!).
    • Transient Stability: Fixed divide by zero when simulating VHVDC1 when Rdc = 0 in the power flow model and also L = 0 in the dynamic model.

April 13, 2021

Features and Improvements

  • QV Curves: On the QV dialog fixed the location of the browse button that allows selection of an output file.
  • Bug Fixes

    • Transient Stability: Made initialization of SCL2C more robust.

April 8, 2021

Features and Improvements

  • File Formats: Device status of <= -3 when reading an EPC file now means to delete the element. Previously we had been using status = -4 to delete an element. Devices are not actually deleted, but the Flag for Delete in EPC will be set to YES.
  • Transient Stability: modified log message that says something like "1012 more ..." to say "1012 more MVABase changed" instead to make it more clear.
  • Bug Fixes

    • Oneline Diagrams: Fixed an access violation when Auto Inserting buses.
    • Transient Stability: Bug fix for OEL5C. State IntegratorTOEL was not being set.

April 7, 2021

Bug Fixes

  • Oneline Diagrams: Fixed bug saving oneline diagrams. The program appeared to hang when saving oneline diagrams because of some unnecessary calculations for groups. We've fixed the problem by only doing calculation once.
  • Transient Stability: SCL1C is now more robust during initialization
  • Transient Stability: If Modify Limits is chosen in Transient Stability Options, and if a UEL1 model feeds into a exciter's HV gate, then UEL1 limits VUImin and VULmin are modified to prevent initial limit violations
  • Transient Stability: When choosing to either Copy or Print All Charts and Title Block, the Title Block was chosen then the bottom and right gray boundary edge on the image created was missing. This has been fixed.

April 2, 2021

Bug Fixes

  • File Formats: Fixed a bug that would cause contingency violations stored by violated element to not appear properly after loading a PWB file. The PWB file still contained them, and after this patch they will be properly shown after loading the same PWB.
  • Transient Stability: Fixed a bug with PSS3C not passing the correct parameters and causing an access violation.

April 1, 2021

Bug Fixes

  • Sensitivity Calculations: Fixed bug that was causing inconsistent TLR results after sequential power flow TLR calculations. The issue was the inconsistent inclusion of phase shifters in the TLR matrices. This has been fixed by checking if the matrices have been built with phase shifters and rebuilding if needed.

March 31, 2021

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): When specifying a Source or Sink that cannot be found for a Direction object when loading from an auxiliary file, put error message in the log that the Source or Sink will be set to Slack instead.
  • Case Information Displays: Added TSContingency string grid table to the customizable tables. Now the customization of the Transient Contingency table can be saved.
  • Case Information Displays: Added nine superarea voltage fields showing min/max/avg for pu voltage, voltage angle (degrees) and voltage angle (rad).
  • Case Information Displays: Added ability to specify generator voltage setpoint and setpoint tolerance in kV. Added generator field to show the RegBus Nom kV.
  • Case Information Displays: Added TSContingency string grid table to the customizable tables. Now the customization of the Transient Contingency table can be saved.
  • Case Information Displays: SendToExcel script command will no longer change the workbookname and worksheetname to uppercase.
  • File Formats: Added optional parameters filtername and AppendFile to the CTGWriteFilePTI script command. The filter is applied to the Contingency object type to specify the contingencies that should be saved to file. All contingencies are saved by default. Set AppendFile to YES to append to an existing file or NO to overwrite an existing file. File is overwritten by default.
  • File Formats: In various places where contingency files in the PTI CON format are saved in the GUI a prompt will appear if the file already exists asking the user if the file should be overwritten or appended.
  • Oneline Diagrams: Added an InjectionGroup field.
  • Time Step Simulation: Changed time domain simulation so a reset actually resets the time to the start time.
  • Transient Stability: New transient stability fields for UEL/OEL/SCL. UEL/OEL dynamic models now have a transient stability integer field called "Activation Status". SCL dynamic models now have two transient stability integer fields called "UEL Activation Status" and "OEL Activation Status". Possible values are 0 (Idle), 1(Engaged) and 2 (Saturated).
  • User Interface Dialogs: Added ability to show all area supply or demand curves for a super area.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Corrected generator variable name RegVoltkVError to RegBuskV (it has always showed the actual kV)
    • Oneline Diagrams: Fixed bug associated with the display of multiple grouped objects, mostly when at least one of the objects is not a text object, like a background rectangle.
    • Oneline Diagrams: Fixed a bug where Snap To Grid was not being returned to its previous value after being temporarily set to True
    • Sensitivity Calculations: When using consolidation with a full topology case, calculations for shift factors and PTDFs may not have been correct when using injection groups containing bus participation points as the source or sink. This has been fixed.
    • User Interface Dialogs: Fixed bug with TGen.MWLambda when fuelcost + extrafuelcost = zero. This would only affect economic dispatch or the code showing a supply curve so the bug would not be common.
    • User Interface Dialogs: Modified generator, area and superarea charts to handle negative marginal costs; also provide access to options so curves can be customized, though right now the change are not stored.

March 24, 2021

Features and Improvements

  • Difference Case Tool: Custom integer, custom float and custom string fields can now be included or excluded when in difference or change mode. This allows a user to populate these custom fields with values they want to be seen under all Difference Case Modes so that the custom fields act like an identifier for the object. Previously if a custom integer had not changed then in difference mode it would show a zero and in Change Mode it would say _same_.
  • Transient Stability: Transient contingencies now have an option to Include RAS for individual contingencies. Previously RAS was always included.
  • Bug Fixes

    • Difference Case Tool: Expanded and corrected functionality for saving Difference Case elements to EPC file format. Interfaces and injection groups can now be saved as difference case elements. Corrected use of Aux Export Format for saving only records that have changed.
    • File Formats: Modified MATPOWER format read to correctly handle more than double circuit lines. MATPOWER itself does not support line circuit numbers, but does allow multiple circuits. The issue was when PowerWorld was not correctly assigning unique circuit IDs when loading a MATPOWER case when their were more than two circuits.
    • Time Step Simulation: Fixed some issues associated with Area ED control, including adding support for negative marginal costs. On the Time Step Simulation 1) added an option to not scale the area and zone load based on out-of-service loads, and 2) added the ability to save a pwb file at the end of each time step. Both options are available on the Time Step Simulation, Options page.
    • User Interface Dialogs: Fixed bug associated with showing the Switched Shunt dialog from a quickpout in the edit mode when the case has not been in the run mode.

March 5, 2021

Features and Improvements

  • General: Fixed a bug with line length not been saved when inserting a new branch.