Simulator 19 Patches

New Features

Bug Fixes

Date

March 8, 2017

Bug Fixes

  • File Formats: Fixed an "list index out of bounds error" that would occur when loading a UCTE file if the last line of the file was any of the headers starting with ##
  • File Formats: Modified so that Balancing Authority names are populated when loading the hdbexport CSV file. Balancing Authorities are not really in the hdbexport CSV, but we just create Balancing Authorities which are the same as the Area records.
  • File Formats: Fixed an error that would only occur if loading an hdbexport CSV file which had zero interfaces defined.
  • File Formats: Fixed access violation when using the difference flows tool option to save out case changes to EPC. The access violation would result when trying to write out any deleted transformers to file.
  • Oneline Diagrams: Fixed potential access violation in Oneline Viewer when opening a large number of onelines. There is a Simulator Environment option that specifies the maximum number of open onelines. This was interacting with the oneline viewer in bad ways after a large number of oneline was opened. It was closing a oneline without the oneline viewer being property notified this was occurring. The oneline viewer will now allow the one to gracefully close but leave the tab alone. If you click back on the tab, the oneline will then be automatically reopened.
  • Power Flow Solution: For 2-terminal DC lines, when the converter step size was set to 0.0000, Simulator would set the firing angle to the minimum firing angle and then calculate the exact tap ratio necessary to meet the desired voltage schedule for the converter. This functioned fine, but this mode of operation for the 2-terminal DC line was not then enforcing the maximum tap ratio. This patch fixes this so that if the maximum tap ratio would be exceed in this situation, then we instead set the tap ratio to the maximum tap and allow the firing angle to increase above its minimum firing angle limit.
  • Power Flow Solution: For multi-terminal DC Converters, when the tap step size was 0.0000, Simulator was treating the tap ratio as a fixed value and not moving it. This has been changed so that instead it behaves like the 2-terminal DC line and fixes the firing angle at its minimum value and allows the tap ratio to be calculed to meet the voltage schedule. The maximum tap ratio is then still enforced however in which case the firing angle is set above the minimum firing angle.
  • Transient Stability: Fixed an error with editing the IThres values for the DISTRELAY model when either loading from an AUX file or when editing in the model explorer.
  • Transient Stability: Allowed for DISTRELAY to plot all 4 relay zones.
  • Transient Stability: When using distributed computing features of Simulator, and using the special string such as @CASENAME, and also choosing to store plot images as you run, the plots were not properly including the case name. This has been fixed.
  • User Interface Dialogs: Fixed potential Access Violation when opening the filter visualization
  • User Interface Dialogs: Modified the Transformer Control dialog so that when changing the Control Type, we do not automatically change the RegMin, RegMax, TapMin, TapMax, and Step values without asking the user if they would like to do this.

March 1, 2017

Features and Improvements

  • Case Information Displays: Added dc line status as a field that is available with the dc line case information display.
  • Case Information Displays: Custom expressions and custom string expressions can now be deleted from their respective case information displays.
  • File Formats: Added the ability on the File Formats Environment Options of the Simulator Options dialog to export a set of a Pattern files which describe all the fields that Simulator knows how to read from the hdbexport CSV files.
  • Power Flow Solution: When using the bus integer field "Priority" to influence the slack buses chosen, Simulator was using that integer even if the bus did not have any CLOSED generators. This meant that if the bus with the highest priority integer did not even have a closed generator then the island would end up being disconnected because no viable slack bus was chosen. This has been fixed so that any bus without any closed generation is ignored in the choice of a slack bus regardless of the Priority specified.
  • Transient Stability: Improved the network boundary convergence for handling current injection machine models

February 27, 2017

Features and Improvements

  • Bus View and Substation View Onelines: Added additional scaling in BusView for high resolution displays
  • Simulator Automation Server (SimAuto): Added SimAuto commands "Hide" and "DangerousVisibleMode" to toggle application visibility while running SimAuto. We have named this "DangerousVisibleMode" so that the user will use this feature with caution. This may be very useful to you, but you may also create some bad interactions if you are running a SimAuto process on a presently visible Simulator window and at the same time clicking on features inside Simulator. Use this new feature with caution.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug saving bus injection group participation points to an auxiliary file. The bus identifier was saved as a blank.
    • Contingency Analysis: In the Auto-Insert Contingency dialog, there where options for filtering branches based on either the "Lower Voltage" or "Higher Voltage". The captions on these buttons were incorrect and the opposite of what they should have been. This has been fixed.
    • File Formats: Fixed bug where transformers given a configuration of DeltaWye or WyeDelta were not being given the correct connection code when exporting to a SEQ file.
    • Power Flow Solution: Messages were being written to the log about switched shunts that had a voltage regulation range that conflicted with the generator setpoints. This was done even whe the switched shunt was set to AutoControl=NO. These log messages are no longer written.
    • Transient Stability: Fixed transfer tripping logic of the ZLIN1 model

February 15, 2017

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Changing the error message that shows when loading an AUX file and an unrecognizable section is encountered.
  • Auxiliary Files (SCRIPT and DATA Sections): In the SetScheduledVoltageForABus script command, the objecttype BUS is no longer required when identifying the bus. Appropriate key fields can simply be used without the objecttype. If the bus cannot be found, the script command will not result in a fatal error that will prevent other script commands in the same aux file from processing.
  • Case Information Displays: Added Bus kV Actual, Bus Per Unit Magnitude, and Bus Angle (degrees) fields for Line Shunts for the bus at which the shunt is located.
  • Contingency Analysis Tool: Before running distributed contingency analysis, make sure all of the dialog options are set with CTGOptions.
  • Contingency Analysis Tool: When storing the WhatOccurredDuringContingency objects for Open actions we also write out a brief string indicating how much MW or MVA was opened by the action. With the "open with breakers" actions however you would need to look at the dynamic elements that were created to see how much flow had been opened. This patch adds the additional feature of also indicating how much flow was opened on the "open with breakers" element directly.
  • Contingency Analysis Tool: modified so that the WhatOccurredDuringContingency objects have the ability to define CustomExpressions and CustomExpressionStrings.
  • File Formats: Modified reading area records to set the area control to Off AGC if the (absolute value) difference between the desired Pnet and actual Pnet read for an area was greater than 5X the tolerance given.
  • File Formats: Modified writing switched shunts that are now set to AutoControl = NO so that they are written to the EPC file as FIXED control. This prevents them from being read back in on some other form of control and moving, when their autocontrol = no really meant they were at fixed output. This will lose whatever type of control the switched shunt may have been set to in Simulator, but prevents the VAR output from changing to something else when read in from the EPC file.
  • GIC: Added ability to show GICXFormer NeutralR on case info, and change LineShunt GIC R values.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug loading MultiSectionLine object type from an auxiliary file when required fields were not included in the file. The multisectionline object is a special object that has required fields that are not really required when creating the object.
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug loading DEFDRAWDFACTS object type from an auxiliary file. This object was saved when saving a full case to an aux but it wasn't supported for loading back in.
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with ATCTakeMeToScenario(RL, G, I) script command. The defined scenario was being specified by the RL value only meaning the scenario was always ATCTakeMeToScenario(RL, RL, RL).
    • Contingency Analysis: When calculating the impact of injection changes during linear contingency analysis, do not include the impact on branches that are consolidated. There are certain situations in which large violations were being reported because incorrect injection impacts on consolidated branches were calculated.
    • File Formats: When reading the ABB spider model files, removed incorrect setting of the tap min, max, and step size. This code was intended for 3winding transformers but incorrectly added to the 2winding transformer code as well.
    • Power Flow Solution: Fixed a conflict when remotely regulating buses had a mix of both generator at Mvar limits and generators not at Mvar limits. This could result in a generator getting stuck at a limit when it should not be.
    • Scheduled Actions: Fixed an error in using the DateTime as part of a custom expression
      Fixed error in the Duration value of a SheduledAction object
    • Transient Stability: Fixed mistake in validation of the Tf and Tg terms of the PVD1 model.
    • Transient Stability: Added hard-coded minimum values for the Lvpnt1 and Lvpnt0 values for various renewal energy machine models such as REGC_A, WT3G, WT4G, WT3G2, WT4G1, PVD1, and PV1G. It is not possible to push current into a fault with very low voltage so having these values set to very low values results in an unrealistic simulation and also causes the network boundary equations to fail. The limits on these values will be set to 0.4 and 0.2 per unit voltage.
    • Transient Stability: for the HYG3 governor, the validation routine was not checking for small values of the Td, Tf, Tp and Tt values. These values should be auto-corrected to be at least a multiple of the timestep or zero.
    • User Interface Dialogs: Fixed access violation that would result when deleting the last custom expression from the Define Expression dialog. This same problem has also been fixed with custom string expressions.

February 2, 2017

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added script command RelinkAllOpenOnelines that does just what the name implies. This should be used with a regular auxiliary file and not a display auxiliary file.
  • Transient Stability: Changed the default time step for transient stability from 0.50 cycle to 0.25 cycle instead.
  • Transient Stability: Modified the default MVA Convergence tolerance in transient stability from 0.1 MVA to 0.01 MVA.
  • Bug Fixes

    • Contingency Analysis: Also fixed the CTGSlveAll script to work with storage to hard drive and not create an access violation.
    • Contingency Analysis: Fixed writing results to hard drive if the results had a comma. Now the strings will be enclosed with "".
    • File Formats: Fixed error when loading a PWB file that would cause the name of the balancing authorities to be lost.
    • Transient Stability: When showing plots for signal that has very little variation, Simulator forces the vertical axis to show at a minimum a variation in the 4th significant digit to avoid confusion of what might appear to be a wildly varying signal when really the values are just varying between 0.9999 and 1.0001. This has always been done in Simulator's transient stability plots, however the feature that checked for this looks for the maximum and minimum value in the vertical AxisGroup to decide this. There was a bug caused because we were considering PlotSeries that were not visible in this determination. This patch fixed this so that plot series which are not visible do not effect this automatic change in the vertical axis
    • Transient Stability: Modified how the LCFB1 model handles the Kdrp parameter. Simulator was using this value as given always, but it was found that other software ignored this value if the Type parameter was 0. Simulator has modified the treament of Kdrp so it now uses the following logic.
      If Type=0, then Kdrp = 1.0
      Else if Kdrp <= 0 then Kdrp = 25
      Else use given Kdrp value.
    • User Interface Dialogs: On the three-winding transformer dialog under the Documentation tab, fixed image showing the conversion of impedances from transformer base to the system base. The ratio of MVABase was flipped on the image. This were handled correctly in the software, just not in this documentation.

January 26, 2017

Features and Improvements

  • Case Information Displays: Added additional fields to 3WXformer objects for MW, Mvar, MVA, Amps, PercentMVA, and Percent (with variations of Pri, Sec, and Ter on each)
  • Bug Fixes

    • Transient Stability: Fixed error in specific situation of incorrectly assigning a switched shunt model (such as svsmo1, svsmo2, or svsmo3) when reading a DYD file. This could occur if a switched shunt did exist at the particular bus specified in the DYD file, but there was NOT a shunt at that bus with the particular ID seen in the DYD file. Simulator was incorrectly assigning the DYD model to the first shunt at the bus instead of treating it as missing as should have been done.

January 24, 2017

Features and Improvements

  • Power Flow Solution: The automatic choice of a system slack bus presently prefers generators with a maximum MW of less than 5000 MW. This is so that fake generators are not chosen as a system slack bus. This has been modified so that we also prefer generators which do not have a negative Minimum MW as well.
  • Transient Stability: Added validation error message for the IEEEG1 model if the parameters K1+K2+K3+K4<=0. That input makes no sense.
  • Bug Fixes

    • Transient Stability: Fixed a bug with applying the option to "Fault Across to Achieve Voltage" to a BRANCH. It was instead taking the fault location as the PU voltage. Now it is corrected.
    • User Interface Dialogs: When choosing to Save Custom Settings on the Display/Column Options dialog when showing a User-Defined Case Information display grid, Simulator was storing the settings as a "DataGrid" objecttype when it should have been using a "UserDefinedDataGrid" objecttype. This has been fixed.

January 20, 2017

Features and Improvements

  • Case Information Displays: ViolationCTG and LimitViol objects did not support the use of DynamicFormatting. This has been fixed in this patch.
  • File Formats: Added support for reading the Balancing Authority information from the EPC file format
  • Oneline Diagrams: When inserting new Circuit Breaker objects to a oneline diagram the Shape is normally set the "Use Default". This has been changed so that
    1. For a branch with BranchDeviceType = Disconnect or Load Break Disconnect, then a Shape is set to "Switchgear"
    2. For a branch with BranchDeviceType = Ground Disconnect, the Shape is set to "Earthing Switch
  • Bug Fixes

    • File Formats: Fixed a bug reading in Scheduled Action Statuses from AUX file.
    • File Formats: Modified writing out data to the MatPower format to use TAB characters as delimiters instead of spaces.
    • File Formats: modified to read CB2 records correctly from the hdbexport CSV file if they are found.
    • GIC: Fixed the treatment of resistance associated with SwitchedShunt objects when perfomring GIC calculations.
    • Oneline Diagrams: Fixing an issue where right clicking on a background object would do nothing. Previously it used to pass clicks to the oneline background, but with the new rotation code, it stopped doing that. Now, it will pass clicks to the background unless the object is linked to a model object.

January 17, 2017

Features and Improvements

  • Contingency Analysis Tool: Added the ability to change between Normal Names and variable names for the fields in the Save to Hard Drive option in CTG Tool.
  • Bug Fixes

    • File Formats: Fixed access violation that could occur when appending a PWB file.
    • File Formats: The power flow option for "Backing off generator Mvar limits immediately" was not being saved to a PWB file. This has been fixed.

January 13, 2017

Features and Improvements

  • Contingency Analysis Tool: added the ability to right-click on an object in a case information display and under the object-specific menu is a button for "Show Dependency Explorer". This will open the Depenendency Explorer to the object that had been right-clicked on in the case information display.
  • Contingency Analysis Tool: Modified the Dependency Explorer so that it not shown as a permanently focused form. You may now navigate through other dialogs while the Dependency Explorer remains open.
  • Power Flow Solution: Modified the new Contingency Analysis option "Prevent new island without enough controllable generation" add in the January 9, 2017 patch. The MaxDeviation value used in this algorithm will now be based on either 1% of the new island load with a bound on this value of between 10% and 100% of the CTG_Options CAGCToleranceMVA. Also modified so that this is only done on a new island which represents less than 10% of the total case load.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: Fixed access violation when selecting a disconnected bus as part of the ATC transfer.
    • Contingency Analysis: Improved the behavior of writing all contingency resutls to hard drive. It will now include Custom Monitors.
    • File Formats: Fixed a bug where using the SaveCase script command or SimAuto function while saving a MatPower .m file would result in an error or the file being incorrectly saved to the root directory of the active drive if the user supplied only the file name of the .m file without the full path included. The file instead should get saved to the current working directory if the full path is not provided.
    • Power Flow Solution: When defining an interface that monitors BRANCH A while also including additional InterfaceElemnts for BRANCHCLOSE A as well as at least a second BRANCHOPEN or BRANCHCLOSE, the calculation of the MW on the interface was incorrect as was the PTDF. This situation was handled appropriately in linearized contingency analysis and the available transfer capability tool, but was not handled in the Interface object calculations. This has been fixed.
    • Security Constrained OPF (SCOPF) Tool: When running LODF matrix, return a consistent value of 1000000 for outages that create islands. Previously it was a large number but appeared somewhat random to the user.
    • Transient Stability: Fixed a bug with generic Limit monitors in transient stability. The OverSpeed setting wasn't working because it was using the under speed setting to set up the value.

January 10, 2017

Features and Improvements

  • Contingency Analysis Tool: Contingency records can now be filtered by LimitViol. This is useful for finding contingencies that have violations of specific elements.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: When using Economic Merit Order Close with iterated ATC method, enforce the economic limits when calculating the PTDFs as part of the linear step portion of the process.
    • General: The www.powerworld.com website security was updated on January 1, 2017 to utilize SSL. When previous patches of Simulator queried the powerworld.com website to determine if a new patch was available, this change caused the following error message to appear: "Simulator 19 is unable to determine if a new patch is available because the following error occurred: "HTTP/1.1 302 Found". (Or some similar message). This patch fixes this problem. In addition, you will notice two additional DLL files being included with the patch update as part of this fix: ssleay32.dll and libeay32.dll. These DLLs are needed to make secure calls to the powerworld website.
    • Transient Stability: Fixed a bug loading repc_a from a user defined model. The Flow Bus was not set.

January 9, 2017

Features and Improvements

  • Case Information Displays: Added new field to Island records to show the Number of Generators, Number of Loads, and Number of Switched Shunts in an island. This can be helpful in determining which islands are of any interest.
  • Contingency Analysis Tool: Added a new option in Contingency Analysis to "Prevent new island without enough controllable generation". This option is not chosen by default so it will not impact you unless it is changed. This option will modify the viability check of newly created islands during the contingency analysis solution to attempt to prevent the creation of an island that results in its new slack generator operating wildly outside of its Min/Max MW limits (as long as that new island has less than 50% of the total system load). To do this we estimate the load, losses and shunt MWs in the newly created island and make sure that the controllable generation in the island (AGC=YES) is such that Simulator has a chance of meeting the load, losses and shunt MWs without operating way outside of its limits. See the following link for more details:
    https://www.powerworld.com/WebHelp/#MainDocumentation_HTML/Power_Flow_Solution_IslandCreation.htm

January 5, 2017

Features and Improvements

  • Case Information Displays: Added two new functions to the Expression for looking for sub-strings inside other strings. These mimic the Microsoft Excel functions Find and Search.

    Find(Find_Text, Within_Text, [Start_Num]). Returns the integer position of the sub-string Find_Text looking inside the string Within_Text. You may optionally instruct us to start the search at character position Start_Num. If Start_Num is not specified, then we start at position 1. The search is case-sensitive. You may not use wildcard characters * or ?.

    Search(Find_Text, Within_Text, [Start_Num]). Returns the integer position of the sub-string Find_Text looking inside the string Within_Text. You may optionally instruct us to start the search at character position Start_Num. If Start_Num is not specified, then we start at position 1. The search is not case-sensitive. Also the Find_Text may include a ? to indicate any single character of an * to indicate any number of characters.
  • Bug Fixes

    • Integrated Topology Processing (ITP): Corrected problems with incremental topology processing during contingency analysis that could lead to inconsistent results depending on the order in which contingencies are processed.
    • Power Flow Solution: If the user hit the Single Solution button when the case had zero buses, an access violation would appear. Modified so that an appropriate message appears indicating there are no buses!
    • Transient Stability: Fixed bug that would not monitor the correct interfaces when defining a transient stability plot with interfaces. The plot would show the correct interfaces but the values for these interfaces would not be the ones monitored during the run.

January 1, 2017

Features and Improvements

  • Oneline Diagrams: Adding additional support for reading DDL oneline diagrams.
  • Oneline Diagrams: Can now execute script commands through oneline links on the oneline instead of the power system. All that needs to be done is to prepend before the script command to be executed and it will be executed within the NWin data model context.
  • Bug Fixes

    • Contingency Analysis: If using distributed computing with contingency analysis and the option to Write to Hard Drive is selected, the run will be aborted. The Write to Hard Drive option is not supported with distributed computing.

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

December 16, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixing a problem with saving conditional formats in AUX files from the dialog.
  • GIC: GICGeographicRegion object type was not allowing the loading of PWGeoPoint subdata section from files that had been created with this section in them. The problem was introduced with the 11/1/16 patch.
  • Oneline Diagrams: Minor fixed for rotated objects and other things when show Areva DDL onelines.

December 15, 2016

Features and Improvements

  • Transient Stability: Added the ability to read the user defined model WTDTAU1 from a DYR file and treat it as the WTDTA1 model
  • Bug Fixes

    • Contingency Analysis: Modified the Branch Field for AggrMVAOverload. Previously it was taking the AggrPercentOverload field and multiplying by the present MVA limit of the branch. The problem with this was that the contingency MVA limit may be different than the normal MVA limit. This has been fixed so that it will use the limit that was used in the contingency analysis results.
    • Sensitivity Calculations: When calculating LCDFs through the LODF sensitivity dialog, the signs of the LCDFs should change if selecting the nearbus of the closed line as the actual to bus of the line. The signs of the LCDFs were the same regardless of which nearbus was selected. This has been fixed.

December 13, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Modified the script command CalculateLODFMatrix() to add an optional sixth parameter for "FilterMonitorInterface". The syntax for this parameter is the same as FilterMonitor which defines the which Branch objects to monitor. FilterMonitorInterface will instead define which Interfaces to monitor and calculate LODFs on.
  • Auxiliary Files (SCRIPT and DATA Sections): modified the script command SetCurrentDirectory() to support the special strings such as @MODELFIELD to specify a special string. Also added support so if the entire string matches the "&ObjectType Key1 Key2 variablename" syntax then it will use that as well.
  • Transient Stability: When showing a hint or dialog showing information about a plot series on a transient stability plot, we previously would show the maximum and minimum Y value experienced by the plot series. We now also show the time (x-value) at which the maximum or minimum value are achieved.
  • Transient Stability: Added a new model WTARA1. This has same features as WTGAR_A. Modified to read USRMDL WTARAU1 into the new model WTARA1
  • Transient Stability: Modified to read USRMDL WTTQAU1 into the new model WTTQA1. Added a new model WTTQA1. This has same features as WTGTRQ_A.
  • Transient Stability: Modified to read USRMDL WTPTAU1 into the new model WTPTA1
  • Transient Stability: Added a new model WTDTA1. This has same features as WTGT_A
  • Bug Fixes

    • File Formats: Fixed bug writing version 33 SEQ file. The CZ0 and CZG flags were not being written. Also The tertiary winding ground impedance was not being read correctly.
    • General: For custom expressions, the ^ operator was defined incorrectly when the inputs were a floating point number as the base and an integer as the exponent. This is fixed.
    • Oneline Diagrams: Fixed selection of oneline display objects. Under some circumstances, Simulator would select an object that should not have been selected when clicking on the oneline.
    • Transient Stability: improving convergence for SVSMO3 models in network boundary equations
    • Transient Stability: When running transient stability simulation for a large number of time steps (>10,000), when re-running the simulation the transient stability dialog would cause a large delay as various parts of the dialog were cleaning up memory associated with the time points. This delay has been fixed by improving how this memory is cleaned up.
    • Transient Stability: When showing a transient stablity plot with a large number of time points, moving the mouse over the plot could make Simulator behave for sluggishly. This was caused by statistics being evaluated on the curve over which the mouse was hoving. This has been fixed.

December 6, 2016

Features and Improvements

  • Transient Stability: Added the ability to read the DYR file USRMDL WTARAU1 (WTGAR_A )
  • Transient Stability: Added the ability to read the DYR file USRMDL WTTQAU1 (WTGTRQ_A)
  • Transient Stability: Added the ability to read the DYR file USRMDL WTPTAU1 (WTGPT_A)
  • Bug Fixes

    • Transient Stability: Fix a bug with zpott not plotting the impedance mho when it was a circle with wt = 0.

December 5, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): modified so that when loading a case using the AUX file format, if a balancing authority number is not given for a bus object, then the area number is used instead. Previously we just assigned a balancing authority number of 1 then.
  • Auxiliary Files (SCRIPT and DATA Sections): Added the DataMaintainerInherit YES/NO field which is enterable for the following objects: Bus, Gen, Load, Shunt, LineShunt, Branch, 3WXFormer, DFACTS, DCTransmissionLine, MTDCRecord and VSCDCLine. Setting this value to NO will prevent these objects from inheriting their DataMaintainer from their terminal bus objects.
  • Auxiliary Files (SCRIPT and DATA Sections): Added the DataMaintainerInheritBlock YES/NO field for a Bus and Substation object. For a Bus, set to YES to block the inheritance of the Data Maintainer for other objects connected to this bus. For example, if this is YES, generators at this bus will not inherit the Data Maintainer from this bus. For a Substation, set to YES to block the inheritance of the Data Maintainer for the buses in this substation.
  • Auxiliary Files (SCRIPT and DATA Sections): Added the DataMaintainerInherit and DataMaintainerInheritBlock fields to the Network Model Auxiliary File Export Format Descriptions
  • Contingency Analysis Tool: Added ability for the LimitViol and ViolationCTG object to return the EMS Topology related strings from the Violated Element such as EMSID and EMSType. Also, for the Branch objects returns the EMSLineID, EMSID2From, EMSID2To, EMSPSID, and EMSCBTyp.
  • Bug Fixes

    • Contingency Analysis: Fixed error with using the Selected, CustomExpression, and CustomExpressionStr fields with a ViolationCTG object. They were returning these values of the corresponding Contingency object instead of the ViolationCTG object.
    • File Formats: When saving out removed elements in EPC snippet file, split out branches and transformers into their own sections if saving a list of branches that also includes transformers. Fixed bug when saving out transformer records when they are saved independently of branches.
    • Transient Stability: When running transient stability and storing results to hard drive, if Windows is not configured to give the user the ability to write files to the directory to which results are being stored, the previously a simple error message say "File access denied" would appear. This has been changed so that a more descriptive error message will appear in the transient stability status edit box indicating the problem.
    • Transient Stability: When saving generator results to hard drive the speed was being saved as nominal Hz instead of 1 pu if the generator had no machine model. This has been fixed.

November 29, 2016

Features and Improvements

  • Case Information Displays: modified where the indication that a field is a Custom String/Integer/Float appears in the hint associated with custom fields. Moved that indication to the end of the string.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When creating buses from an aux file, balancing authorities were being created for every bus in the case instead of just assigning each bus to a specified balancing authority or balancing authority 1. This has been fixed.
    • Auxiliary Files (SCRIPT and DATA Sections): When defining the hard-coded Auxiliary File Export Format Description for Contingency and Transient data, the Custom Fields including DataMaintainer were being added to Gen, Load, Bus, Area, And Shunt objects. The custom fields for these objects should only be included in the Network Model description. This has been fixed.
    • Case Information Displays: When changing the name of an injection group, the internal sorted list of injection groups by name was not properly maintained. This could make subsequent searches for an injection group fail. This has been fixed.

November 21, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added optional parameter to CalculateTLR script command. The new parameter, AbortOnError, allows the user to disable the error message, which would interrupt a series of script commands. To disable the error, set AbortOnError = NO. If AbortOnError is NO, then the error message is printed to the log, but the command does not fail.
  • Contingency Analysis Tool: Modified the Interface OPEN contingency action so that it also opens any generators or loads in the interface. Previously it only opened the monitored branches in the interface.
  • Bug Fixes

    • Transient Stability: When loading the REGCAU1 user-written model from a DYR file, modified so that the parameter Xe is always read as a zero. This is because it has been found that this parameter is not used in the user-written model so it should always be treated as a zero (0.0).
    • Transient Stability: Part of initializing a load which contains a distribution equivalent involves calculating shunt terms on the feeder branch as well as potentially including a shunt on the low side of the transformer. The dynamic load models are then placed at the end of the feeder branch. Later when choosing to OPEN a load Simulator was properly opening the dynamic load models, but was not opening the feeder and transformer of the distribution equivalent. This has been fixed.

November 14, 2016

Bug Fixes

  • File Formats: When loading a case from PWB with many Balancing Authorities, the load can be very slow. This has been fixed.
  • Integrated Topology Processing (ITP): Incremental topology processing with contingency analysis could fail to solve with some system topologies. This has been fixed.

November 10, 2016

Features and Improvements

  • Transient Stability: Modified the floating window that contains Plots for transient stability can be minimized and maximized.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified the script command CTGCompareTwoListsofContingencyResults() so that the filenames specified are processed to look for special strings such as @CASENAME or @MODELFIELD. Also processed special PROMPT tag to indicate that the traditional open dialog should be opened.
    • Auxiliary Files (SCRIPT and DATA Sections): fixed SupplementalData and SupplementalClassification objects so that they support the use of special input syntax of "&objecttype 'key1' 'key2' variable:digits:rod" for editing fields such as CustomString
    • Transient Stability: In the October 7, 2016 patch, we modified the State and Other Fields column headers and field names for the CMPLDW and CMPLDWNF models so that they would indicate a string based on the type of motor. This was working correctly for the Other Fields, but the State fields. The state fields column headers were shifted by 1. This has been fixed.

November 8, 2016

Bug Fixes

  • Contingency Analysis: When using the feature to Compare Two List of Contingency Result, and at the same time using a Custom Monitor that looks at fields of a Contingency Record, an access violation would occur. This has been fixed.

November 7, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Modified so that the special strings in AUX files that use "@MODELFIELD<>" work properly when using them inside an action that specifies a file to open. Previously when using the special @MODELFIELD<> syntax it would return an error saying the file does not exist regardless of whether evaluating the syntax would result in a filename that did exist.
  • Bug Fixes

    • File Formats: When loading the hdbexport CSV file, modified so that the CSV file is read ignoring read to use regional language settings. These files are always written using a decimal as the digit separator.
    • User Interface Dialogs: When showing the filter visualization for an Advanced Filter, fixed a bug when a filter has as conditions other filters.

November 4, 2016

Features and Improvements

  • File Formats: When reading hdbexport CSV file, the files can generally be written in 2 ways

    1. Filtered File: Using a pattern file yields a CSV file with a header section at the top listing all the fields being written for each particular record. Later in the file, those records are written using a simple comma-delimited list of strings where the order of the fields is determined by what was read from the header section
    2. Unfiltered File: Without a pattern file there is not header section and each record uses a syntax of "FIELDNAME=Value"

    It is possible for a user to create an hdbexport CSV file which had some records written using a pattern file and other record written without the pattern file. This is likely not done on purpose and results in a mix of records with some using the simple comma-delimited list of strings with the order determined by the header and other records written using the syntax "FIELDNAME=Value" throughout. Previously Simulator would fail to read a file that was a mix of these record syntax. This patch now handles this situation and will read record types that were not included in the header section as though they are part of an unfiltered file. A warning message is written to the log in red text however indicating this is occurring.
  • Bug Fixes

    • Case Information Displays: Fixed a bug that occurred when using Transient Models to trip during Power Flow Contingency analysis.
    • Case Information Displays: Some fields (Group Order, Subgroup Order, Group Status, and Time Delay) associated with What Actually Occurred data were not being stored when using distributed computing with contingency analysis. This has been fixed.
    • File Formats: When reading an hdbexport CSV file, Simulator must take the PS record field ADEG_PS and assign the negative of this value to the Phase angle of PowerWorld's BRANCH object. Simulator has always done this correctly. However, this also means that any impedance correction table read from the hdbexport CSV file must have the Phase Angle values with the opposite sign as well. Simulator was not properly flipping the signs of the angle in the impedance correction table. This has been fixed.

November 1, 2016

Features and Improvements

  • Transient Stability: added ability to save a set of plot results as a PlayIn Signal object.
  • Transient Stability: Modified saving a PlayIn object to an AUX file so that it automatically stores the associated PlayInInfo and PlayInSignals as well
  • Bug Fixes

    • User Interface Dialogs: Editing a phase shifter phase angle from the Transformer Control Info dialog accessed from the Branch Information dialog while in Run Mode would cause the transformer tap ratio available on the Branch Dialog to also change to match the phase angle. This has been fixed.

October 31, 2016

Bug Fixes

  • Available Transfer Capability (ATC) Tool: Fixed a bug in the ATC tool when monitoring interface MW flows during a contingency, while also having defined the Monitor Direction of the interface as "TO -> FROM".
  • Contingency Analysis: Fixed a bug with incremental topology processing used during contingency analysis that could cause the process to get in an infinite loop. This problem depends on system topology and the ordering of contingencies and would not always occur.

October 26, 2016

Bug Fixes

  • Power Flow Solution: Fixed a very obscure bug when using Island-Based AGC control with a larger convergence tolerance (Tolerance > 0.5 MW). This would not occur with Area/SuperArea control but only with Island-Based AGC control in the power flow solution. The bug could cause the resulting power flow solution to not properly enforce the AGC tolerance and thus have the slack bus move more than it would have otherwise moved.
  • Transient Stability: Fixed access violation that could occur when a ATRRelay triggers the trip of a generator.

October 25, 2016

Features and Improvements

  • Contingency Analysis Tool: Added fields to a LimitViol and thus the ViolationCTG object for showing the Reference State fields in the Comparison Case. Also added fields for the difference between the Comparison and Controlling case for the reference state values.
    ValueRefComp = Compare Two ListsReference StateComparison Reference State Value
    PercentRefChangeComp = Compare Two ListsReference StateComparison Change from Reference State Percent
    ValueRefChangeComp = Compare Two ListsReference StateComparison Change from Reference State Value
    ValueRefDiff = Compare Two ListsReference StateDifference Reference State Value
    PercentRefChangeDiff = Compare Two ListsReference StateDifference Change from Reference State Percent
    ValueRefChangeDiff = Compare Two ListsReference StateDifference Change from Reference State Value
  • Contingency Analysis Tool: Previously, the Percentage field for a voltage limit violation would show a blank value. This has been changed so that the percentage is shown based on the voltage limit. Thus a violation Value=0.90 with Limit=0.95 will show a percentage of 0.90/0.95*100 = 94.74.
    Note "Change" Voltage violations have always shown a percentage which was based not on the limit, but on the Reference State Voltage and this will continue. For example a bus that has ReferenceStateValue = 1.08, LowLimit=0.95, and Value = 1.02 may still report a "Change Bus Low Volts" violation. The percentage field for that limit violation will show 1.02/1.08*100 = 94.44.
  • File Formats: When reading the Areva hdbexport case file, modified reading of CP (switched shunt) records so that the AVR_CP field toggles the Field AutoControl in Simulator to either YES or NO. Previously the AVR_CP determined whether the switched shunt was set to a Distcrete or Fixed mode.
  • User Interface Dialogs: Added a button to Edit Impedances and Taps on the Transformer Voltage and MVABase to the Run Model Branch Dialog. Added notes to make it more clear that the branch dialog shows values on the system MVA and Voltage bases.
  • User Interface Dialogs: increased digits Generator Dialog for generator voltage setpoint and generator regulated bus voltage from 4 decimals to 6 to ensure we show what input data truly is.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that would not allow you to delete CustomMonitor objects using the Delete script command.
    • Case Information Displays: When showing the Regulation Range Target Value for a phase shifting transformer in the case information display, we were showing the value in per unit instead of in MW. This has been fixed.
    • File Formats: When reading the hdbexport CSV file, modified reading of the WTARGET_PS and DEVIAT_PS fields so that if DEVIATE_PS < 0.10 then we treat it as 0.10. Simulator reads these values to determine RegMax and Regmin. This is done so that RegMax ends up slightly different than RegMin. Otherwise when the transformer is turned on control within PowerWorld Simulator it will still not control because there is no tolerance for the control. Same thing was done with VTARGET_XF and DEVIAT_XF, but the threshold used was 0.0001 per unit voltage.
    • File Formats: When reading the hdbexport CSV file, fixed bug reading generator Mvar limits. The VARMAN flag indicates that the RCC should not be used. Instead, manual var limits are specified in the case. The bug was that the var limits were being calculated from the RCC even when the VARMAN flag was set. The logic has been updated so that var limits are not calculated from the RCC if VARMAN is true.
    • Transient Stability: fixed error with showing plots that contained play in signals on them.
    • Transient Stability: The CMPLDW and CMPLDWNF models were using a constant current load for the electronic load component of the composite. This should have been a constant power and has been changed to constant power now.
    • User Interface Dialogs: Modified the Transformer Dialog for entering impedance and tap information on the transformer base. From discussions with customers it was clear that a common mistake was being made on this dialog. Users where changing the transformer's nominal voltage bases to be equal to the system bus nominal voltage and also changing the MVABase to the system MVABase (normally 100.00). In this situation users were then assuming that the R and X series impedances on that dialog would then represent the system base R and X. This was not always correct however if FixedTapTo <> 1.0000. The fixed tap ratio on the To bus side also impacts the conversion of the transformer base R and X to the system base. To help make this clear to users, if the voltages and MVABases match the system base AND the FixedTapTo <> 1.0000, a special note in red text will appear stating "Note: R and X on transformer base will still be different than the system base values. This is because "Fixed Tap To Bus" is not 1.00000. See Conversion Equations Tab for more details."

October 14, 2016

Features and Improvements

  • Transient Stability: When loading a DYR file, added automatic translation of an additional user-written model: USRMDL REECAU1 is translated to REEC_A
  • Transient Stability: Custom strings, integers, and floats are now enterable with transient stability models but the information is stored with their linked objects.
  • Bug Fixes

    • Contingency Analysis: Fixed problems when exporting the Contingency AUX file while using the option "Save Calculated Fields and Custom Expressions".

October 12, 2016

Features and Improvements

  • File Formats: Modified writing in Matpower format so we don't write Marginal Prices if an OPF solution has not been run.
  • Transient Stability: When reading a DYD file, we previously did checks to ensure the order in which dynamic models were read from the DYD. In older versions of other software, if a machine model was not the first model for a generator then subsequent models for that generator were ignored. Simulator had previously opened a dialog asking the user if they wanted to disable these models. This dialog has been removed so that models read from the DYD file are no longer disabled for this reason.
  • User Interface Dialogs: Added buttons on the transformer tab of the branch dialogs to
    "Edit Integer Tap Positions" and "EMS Edit Integer Tap Positions"
    These buttons bring up a dialog on which which the user may edit the tap/phase, TapMax, TapMin and StepSize using the either the integer positions based around 1.0000 tap and 0.0000 phase, or using the integer positions using the EMS convention.
  • Bug Fixes

    • Contingency Analysis: Improved the Dependency Explorer to show the dependency of Custom Expressions and Calculated Fields when they are used inside a Model Expression.
    • File Formats: PowerWorld Simulator and the hdbexport CSV file use a different sign convention on the phase shift angle, thus Simulator will always show phase shifts that are the negative of those seen in the hdbexport CSV file. We were properly handling this when reading the actual phase angle (ADEG_PS), but were not properly handling this when using the step size (STEP_TAPTY). This could result in the incorrect TapMax and TapMin phase angles, although when TapMin = -TapMax they would still be calculated correctly (which was most commonly the case). It would also result in an incorrect translation to the integer tap positions using the EMS convention. This has been fixed.
    • Integrated Topology Processing (ITP): When using incremental topology processing, all islanded generation was not properly accounted for. This has been fixed.
    • Transient Stability: fixed bug in showing the table of Distribution Equivalent objects. This bug was introduced in the October 3 patch and is now fixed.
    • Transient Stability: When choosing to NOT save transient stability results to hard-drive, Simulator was not writing the TSR file, but was still writing the AUX file saving summary result information. This has been fixed so that the AUX file is not written unless the user chooses to save results to hard-drive.

October 7, 2016

Features and Improvements

  • Contingency Analysis Tool: Added a new field to a ViolationCTG names "SourceList" that will be useful when comparing two lists of contingencies results. This field will indicate which list of results this violation existed in. It will either show Both, Comparison, or Controlling.
  • Transient Stability: modified so that the State and Other Fields listed for the motors of the CMPLDW and CMPLDWNF models will show the name related to the type of motor (MtypA, MtypB, MtypC, and MtypD). Previously the string would show something like "[Type 3 Speed wr]; [Type 1 Bus Freq]". It will now show either "Speed wr" or "Bus Freq" depending on what the model motor parameter types are for that load model.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug on merging buses with GICXFormers.
    • Contingency Analysis: Fixed problem saving contingencies to AUX file.
      An access violation was causing an exception that resulted in skipping over the code that saves to aux file.
    • Transient Stability: When saving transient stability results to hard-drive for LineShunts, Measurement Objects, or Multi-terminal DC line objects, the order of fields in the *.TSR file were not being written properly so those results could not be read appropriately. This did not effect results for Gen, Bus, Load, Branch, or DCLine objects, but could effect other results.
    • Transient Stability: The LD1PAC model (as well as the single phase motor portion of the CMPLDW and CMPLDWNF models) automatically calculate a voltage at which the operating curve transitions to the stalling curve for the PQ characteristic. Previously if this voltage (Vstallbrk) ended up below the input voltage Vstall, then Vstallbrk was modified to be Vstall instead. The problem with this was that it can lead to a large discontinuity in the PQ characteristic and can also result in a highly unrealistic load that has a steep increase in P/Q load as voltage decreases. We will now no longer enforce that Vstallbrk be less than Vstall. This means that Vstall is only used with Tstall as a threshold/timer that causes the PQ characteristic to transition to the stall curve and remain there.
    • Transient Stability: Modified the behavior of load tripping that causes a fraction of a load to be tripped. Previously, after the load had reached a total trip amount of more than 100%, we would automatically open the load. This wasn't really necessary before because the multiplier applied to the load at the network boundary equations was moved to zero and thus the load acted as completely open anyway, however we had done this in the past to be less confusing to the user. However, the CMPLDW and CPMLDWNF models include an ability reconnect a portion of the load even after tripping 100% of the load. Thus the old behavior would not allow the load to be reconnected once you had removed 100%, but it would if you were at 99% removed. We will now no longer trip a load once the scalar gets to zero.

October 4, 2016

Features and Improvements

  • Transient Stability: For stability dynamic model tables, added ability to show Custom String, Custom Float, Custom Integer, Custom Expression, Custom String Expression and Calculated fields of the object to which the dynamic model is assigned.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified so that when running the script command SaveCase(), Simulator will automatically update the main window's Caption to show the name of the case as it has been saved. Previously this would not update immediately which could be confusing.

October 3, 2016

Features and Improvements

  • Case Information Displays: Now string grids allow entering via movement from one of the arrow keys or page up or page down.
  • Oneline Diagrams: Clicking on a link in an Allstom oneline now uses the Oneline Browsing Path to search for onelines to link to. The path specification is searched in order, from top to bottom. If a matching oneline isn't found within the Oneline Browsing Path, it returns to the old method of searching through the path of the oneline that contains the link that was clicked.
  • Transient Stability: Added a new model DC line model CHVDC2. This model includes the simulation the RLC circuit of a 2-terminal DC line in the transient stability environment.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified new @MODELFIELD special string feature so that it could be used in a script command when specifying a filename. Simulator was calling this an illegal filename because of the < and > characters which are not valid characters in a Windows filename. These characters are removed when executing the command though so this error should have been skipped.
    • Auxiliary Files (SCRIPT and DATA Sections): fixed error in SaveData() script command introduced in September 28, 2016 patch which caused an access violation.
    • Case Information Displays: Fixed bug in All Display Objects table where ID1 field was displaying the device number for bus, gen, load and shunt objects as a hexadecimal number instead of an integer
    • File Formats: We were seeing more RAW files that had records with missing fields at the end of records. We modified to gracefully handle this and assign default values for these fields.

September 29, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command ObjectFieldsInputDialog("Object String", [fieldlist]); where Object string is the string defining which object you're showing fields for and fieldlist is a list of variablenames as done in other script commands. Examples are as follows for editing several generator fields
    ObjectFieldsInputDialog("Gen 16445 'A'", [BusNum, ID, BusName, MW, Mvar, VoltSet, AGC, AVR, MWMin, MWMax]);
    ObjectFieldsInputDialog("Gen BusName_138.000 'A'", [BusNum, ID, BusName, MW, Mvar, VoltSet, AGC, AVR, MWMin, MWMax]);
    ObjectFieldsInputDialog("Gen 'my label string'", [BusNum, ID, BusName, MW, Mvar, VoltSet, AGC, AVR, MWMin, MWMax]);
  • Oneline Diagrams: Added various support throughout for rotating background objects. Also modified so that objects can be rotated about their center instead of always around the upper left corner.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): The name of a field or model expression used in an injection group participation point was being set to all uppercase. This has been fixed.
    • Contingency Analysis: Made some modifications to contingency analysis while using topology processing that should eliminate some unsolvable cases.
    • Transient Stability: When loading a MCRE *.RWM file, if the fraction of P and Q (FP and FQ) values for generators at one bus did not sum to 1.00 then we were not properly normalizing the FP and FQ values for use when splitting the generators. This has been fixed.

September 28, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): There are various places in defining a filename in a SCRIPT command and also in the various places in transient stability and PV curve plotting where a special string can be used such as @CASENAME or @DATETIME to signify that a string be written signifying something. This has been expanded and generalized so that the following format can be used to specify any field of any object be included in a string.
    @MODELFIELD

    An example of this would be the following to write the Area Name at the from bus of the branch from bus 501 to bus 456 circuit 1.
    @MODELFIELD
    Another example of this would be to the following to write the per unit voltage of a particular bus.
    @MODELFILED
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified the LogAdd, MessageBox, SaveDataWithExtra, WriteTextToFile, and SendToExcel script commands so that they process the special fields such as @CASENAME during the actual execution of each individual script command. Previous we would read an entire block of SCRIPT (between the curly braces) and convert the strings based on what something like the name of the case was before all the commands in that block were run. The problem with this was that some of the commands in that sequence may change the values.
    • Contingency Analysis: fixed error in showing the Violated End NomkV on a branch violation in the ViolationCTG case information display. This was recently added but was showing blanks.
    • Oneline Diagrams: Fixed a bug auto-inserting lines on subatations -- lines with stubs specified are drawn in bays as usual, while lines without stubs specified are drawn from the center of the substation object.
    • Power Flow Solution: Fixed coordination of multiple generators at the same bus regulating a remote bus voltage when some generators are at a Mvar limit while other generators are not at a Mvar limit. Under rare circumstance this could cause a solved power flow to report that it was unsolved even though the mismatched were zero.
    • Transient Stability: Previously in Simulator when loading in DYD and DYR files, Simulator would automatically take the values given for Xdpp and Ra (or Xdp depending on model) and populate the internal impedance of the generator from the associated dynamic machine model. This will not impact Simulator's transient stability simulation, but we should still not be doing this.

September 27, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command "MessageBox(str)", which takes a single, string parameter, and pops it up in a informational dialog.
  • Integrated Topology Processing (ITP): The option to not monitor radial lines and buses with limit monitoring settings will be ignored if the user has the topology processing add-on and the option to use topology processing is checked.
  • Integrated Topology Processing (ITP): When monitoring buses for contingency analysis or showing base case violations with limit monitoring settings and using the option to only monitor the primary bus for each superbus, the primary bus, bus with the highest low voltage limit, and bus with the lowest high voltage limit will all be monitored (assuming they are different buses) so as not to miss any possible violations.
  • Transient Stability: Modified captions of plot series when showing a value that represents the %, Dev, %Dev, or d/dx of the a particular value.
  • Transient Stability: Modified the loading of PlayIn, PlayInSignals from an AUX file so that they the aux file loads quickly. Previously it was loading very slowly.
  • Transient Stability: Modified so that PlayIn signals values can be shown in the Case Information table when plotted with Time Results from RAM. Previously they could be plotted, but they would not show up when showing the values in the case information tables. The values shown for the PlayIn signals in these tables will be the interpolated values that match those shown at the times given by the other results.
  • Transient Stability: Added the ability with the CMPLDW and CPMLDWNF models to show the Static MW, Static Mvar, Electronic MW, and Electronic MVar as OtherFields for reporting.
  • Transient Stability: Add the field to show the tap ratio of the transformer which is part of the Distribution Equivalent for a Load. This field is available on under the Feeder Other fields.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When saving a case using either a script command or via SimAuto, the string indicating the name of the case presently open was not being updated. This meant that the use of the special @CASENAME string in various script commands or on plotting strings was not being updated. This has been fixed.
    • Contingency Analysis: An access violation could result during contingency analysis if a contingency action is referencing a model expression that does not exist. This has been fixed.
    • File Formats: When writing out transformer to a RAW file using the CM=2 option, the MAG2 value was not being properly converted to transformer base per unit current. This has been corrected
    • Transient Stability: The Simulation of the CMPLDW and CPMLDWNF load models were working correctly under the following circumstances, but the result reporting of pieces of the load were not outputting correctly. The Total MW and Mvar was correct, but the A, B, C, D portions of the motor loads could be incorrect.
      * If Motor A was set to 0% then the results for A would actually show B (B would show C, and C would show D)
      * If Motor A and B were set to 0%, then results for A would actually show C
      And so on. This has been fixed.

September 23, 2016

Features and Improvements

  • Case Information Displays: Changing string grids so that they behave more sanely. If you enter a value and click away, depending on where you click, the string grid will perform one of these things:
    1) If you click within a valid cell in the string grid, the value will be put into the old cell.
    2) If you click within the grid, but *not* within a valid cell, the value will be discarded.
    3) If you click outside of the grid entirely, the value will be put into the old cell.
    This has been changed so that clicking away *always* puts the value. Furthermore, pressing the Escape key while typing will cancel entry and return to the old value.
  • Contingency Analysis Tool: When a contingency solution results in the change in MW injection (usually loss of generation) such that the generators in the island are unable to make-up for this change, then Simulator will return the string "RESERVE LIMITS" in the Violations columns for a particular contingency. This is done to indicate that the contingency result may not be reliable because all the additional make-up power has gone to the island slack bus. In this patch we have modified it so that if the island has ZERO generators which are set to (AGC=YES) and (PartFact>0) then we do not bother returning the RESERVE LIMITS flag.
  • Contingency Analysis Tool: Modified the various Contingency fields showing the number of violations so that if the Solved field is equal to "RESERVE LIMITS", then we now show the number of violations that were recorded anyway. Previously we showed the string "All make-up power at limits". We will now assume the user can look at the Solved field to know this. The violations are still recorded when "RESERVE LIMITS" is listed, so showing the user this count is useful.
  • Contingency Analysis Tool: On a Contingency table, added color highlighting to the Solved and various violation count columns. If the contingency has Processed=YES, then the colors are based on the Solved field as follows
    * YES : normal fill color
    * NO : light red fill color
    * ABORTED : light orange fill color
    * RESERVE LIMITS : light yellow fill color
  • File Formats: Updated the ABB EMS contingency parser to use different names. The number has been removed from the contingency name.
  • Power Flow Solution: removed some log messages about dropping MTDC converter setpoints if the drop in the setpoint is less than 0.1%.
  • Transient Stability: Added a new Conversion of value to plot option for Derivative. This automatically calculated the digital derivative of the signal by taking differences between values and dividing by the time difference.
  • Bug Fixes

    • Transient Stability: When plotting from the hard-drive values, the plot series always plotted the "Actual Value" regardless of the option set for Conversion of Value to plot. Hard drive plotting has been fixed to correctly perform Percent of Initial Value, Deviation, and Percent Deviation

September 21, 2016

Features and Improvements

  • File Formats: When loading the hdbexport CSV file, modified the default label creation for LN and ZBR records to ensure that the most basic ZBR%LINE.ID$ZBR.ID and LN$LINE.ID$LN.ID are the primary label. These are really all that are needed as unique identifiers for the LN and ZBR records so should be the primary label.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): The CalculateLODFScreening script command was not functioning and throwing an access violation. This has been fixed.
    • Oneline Diagrams: Fix a potential access violation when loading background pictures from a display auxiliary file.

September 19, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug when using the Move script command to move a load to a new bus and the ID was the same as a load at the new bus.
  • Case Information Displays: There was an error when changing the name of a model filter through the model explorer. The references to the model filter from other model filters were not being updated. This has been fixed.
  • File Formats: When reading the ABB Spider text files, modified setting winding tap max, min, and step values.
  • Oneline Diagrams: Fixed access violation that could occur when Copying a display object to the clipboard when using Floating Windows Mode.
  • Transient Stability: Fixed bug with CLOD models when there only small motors and no large motors and transient stability rsults were being saved to harddrive.
  • Transient Stability: Fixed error in implementation of the Vrmax and Vrmin limits when Flimf = 1 for the REXSYS and REXSY1 exciter models

September 15, 2016

Features and Improvements

  • Contingency Analysis Tool: Added 7 new fields for a LimitViol object which give information about the violated end of the violated element. (BusNumViolEnd, BusNameViolEnd, NomkVViolEnd, AreaNameViolEnd, BANameViolEnd, ZoneNameViolEnd, SubNameViolEnd). These fields are then available in the ViolationCTG object as well with the field names LV_BusNumViolEnd, LV_BusNameViolEnd, LV_NomkVViolEnd, LV_AreaNameViolEnd, LV_BANameViolEnd, LV_ZoneNameViolEnd, LV_SubNameViolEnd.
  • Bug Fixes

    • Transient Stability: There was a bug with passing the HYGOVR1 information over to the transient stability simulation would would cause the simulation to fail. This has been fixed for the HYGOVR1 model.
    • Transient Stability: The Velcl term of HYGOVR1 treats positive values as the negative limit. This has been fixed.
    • Transient Stability: Added initial limit violation check on Pmax and Pmin on the HYGOVR and HYGOVR1 model
    • Transient Stability: When user input specifies a non-linear gain curve which has the same X coordinate for the last 2 points and also expects the curve to extrapolate past the end of the curve, then simulator was return an infinite results. This situation will now just return the final point of the non-linear gain.
    • Transient Stability: Modified the error check of very small time constants to force the value to zero if a zero is allowed. Previous if the input data had a value less than 1E-6 then it would leave it at that value.
    • Transient Stability: There was a bug with passing the DC3A information over to the transient stability simulation would would cause the simulation to fail. This has been fixed for the DC3A model.

September 14, 2016

Features and Improvements

  • Case Information Displays: For expressions and model expressions can now edit the expression string, Blank is Zero, and Evaluate In Ref, fields directly in the case information displays.
  • File Formats: When reading the hdbexport CSV file modified to interpret the VARMAN_UN field for a UN record to indicate whether to use the Capability Curve. If the value is TRUE, then the Capability Curve will not be used.
  • Bug Fixes

    • Contingency Analysis: Modified the reading of the ABB Contingency File because the white space in the fixed column format had changed
    • Transient Stability: Starting with the August 10, 2016 patch the user can now enter the minimum MW and P/Q ratios for which a complex load model will be used. Previously this was hard-coded to 0.1 MW. There was a bug however in that the value being enter in MW such as 0.5 MW was being treated internally as though it was in per unit. Thus on a 100 MVABase specifying a value of 0.5 really was limiting loads to 50 MW or more. This has been fixed.
    • Transient Stability: Fixed reading the new translation of the USRMDL GENTPJU1 model. The order of the parameters was not correct.
    • Transient Stability: Fixed reading the TIOCR1 model. It was reported an invalid number of parameters incorrectly when reading the DYR file.

September 13, 2016

Features and Improvements

  • Contingency Analysis Tool: added hints for the edit boxes and labels shown on the field editors of the Dependency Explorer.
  • Transient Stability: When loading a DYR file, added automatic translation of additional user-written models.
    USRMDL GENTPJU1 is translated to GENTPJ
    USRMDL REGCAU1 is translated to REGC_A
    USRMDL REECBU1 is translated to REEC_B
    USRMDL REPCAU1 is translated to REPC_A
    USRMDL HYGOVRU is translated to HYGOVR1
  • Bug Fixes

    • Transient Stability: Corrected the name of the model HYGOVR1. It had mistakenly been named HYGOVRU.

September 7, 2016

Features and Improvements

  • Contingency Analysis Tool: Modified so that as the selection changes on the Contains tree view, the logic visualization follows that change in selection just as the window showing the object fields changes.
  • Contingency Analysis Tool: Modified so that the Maximum Depth of the Contains TreeView can be changed by the user by right-clicking on the Contains Tree View.
  • Contingency Analysis Tool: Modified the Back/Ahead buttons on the Dependency Explorer so that duplicate objects are not listed consecutively in the lists.
  • Bug Fixes

    • Contingency Analysis: fixed error that could occur on the Dependency Explorer when showing a InterfaceElement object in the dialog
    • Contingency Analysis: modified so that when showing either an InterfaceElement or PartPoint inside the Dependency Explorer the proper fields are shown in the dialog for defining the object. Previously they were just no fields shown for these 2 object types.
    • Contingency Analysis: When using an interface CHANGEBY or SETTO contingency action, no longer check to see if the total flow for the interface is in the same direction as the change, meaning that no elements can be opened to bring about the change. Instead check each individual element and only open those that are in the opposite direction of flow.
    • Contingency Analysis: Fixed a problem that could cause an interface CHANGEBY or SETTO action to open too many elements.
    • Contingency Analysis: Fixed an access violation caused by using the Apply Selected Contingency option for a contingency containing an interface or injection group action.
    • Fault Analysis: Fixed a bug when calculating a fault using IEC 909 or Flat Classical pre-fault profiles. If a transformer has a non-zero phase shift, the phase shift should be ignored during a fault calculation with either of these pre-fault profiles. Previously the phase shifts were included in the calculation of fault currents on transformers, resulting in incorrect reported values.

September 6, 2016

Features and Improvements

  • File Formats: When reading the hdbexport CSV file, modified to reading the CP record to look up available values of MvarNom using the pointer to an I__TAPTY_CP table if present in the CP record. If present, then the I__TAB_TAPTY pointer from the I__TAPTY_CP record is used to get the TAB record defining the values of nominal Mvar. Presently the list of available MvarNom values are assigned to best fit into 8 blocks of the switched shunt record. This feature is being used to represent Variable Shunt Reactors in the hdbexport CSV format.
  • Transient Stability: Added ability to see the present interface flow information when viewing the transient stability state information in the user interface.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When saving an aux file, fixed problem with writing out the name of an interface when saving contingency elements and remedial action elements using an interface with a CHANGEBY or SETTO action. The interface name was blank so the actions could not be created when loading the aux file back in.
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed an access violation when using interface contingency actions for CHANGEBY or SETTO and the interface includes other interfaces.
    • Case Information Displays: When some Calculated Fields exist in the case, but the object table being shown does not support using any of the existing Calculated Fields, then Simulator was not showing the Calculated Field folder in this list of available fields. This has been modified so that the folder appears along with the entry saying "Calculated Field(no Calculated Fields defined yet that this object can use)"
    • File Formats: Modified reading of the MatPower format to automatically assign unique circuit IDs to parallel branches given in the file.
    • File Formats: There was an error in loading a RAW file if the 2 line header had blank lines. This was causing the first 1 or 2 initial buses in the model to not be read. This has been fixed.
    • General: Fixed bug when viewing an Advanced Filter visualization that could cause an access violation.

August 31, 2016

Features and Improvements

  • Contingency Analysis Tool: Added a new dialog called the Dependency Explorer. This is available in 2 places
    1. Under the RAS + CTG Case Info menu in the Tools Ribbon Tab
    2. On the Contingency Analysis dialog under the Options tab.
    This dialog provides a very nice way to navigate through the dependencies that Contingency and RAS elements have with the various ModelFilter, ModelCondition, ModelFilterCondition, ModelConditionCondition, ModelExpression, Filter, Condition, and associated objects referenced by all of these. The user may also edit these various objects directly on the Dependency Explorer dialog. Finally, using a floating Drag/Drop editor window, ModelFilters can be built up graphically directly on a TreeView of these dependencies.
  • Transient Stability: Modified so that a TSContingency object can use a Calculated Field. It presently can only operate on the list of TSLimitViolation or the the TSResultEvent. As an example, this gives the user a way to get a count of the number of events that meet a filter on the TSContingency record
  • Bug Fixes

    • Contingency Analysis: When saving contingency settings to an Auxiliary File, if a ModelExpression referred to a CalculatedField index that did not exist an silent error occurred which resulted in the AUX file not being properly saved. This has been fixed.
    • File Formats: Fixed bug when reading hdbexport CSV file if an ND record ended up referring to an MNL record, but the MNL records VLIM pointer was 0. We were incorrectly assigning the limit group for the bus to the one associated with the last MONGRP read. MONGRPs represent limit groups fore branch records (LN, XF, ZBR). This has been fixed so that the bus is appropriately assigned to the default limit group.
    • File Formats: The August 22, 2016 patch included a fix to write out CNXA value of 0.000 to RAW 33 and 34 files. This fix was implemented incorrectly an the ", 0.000" was being written to the next line in the RAW file instead of to the end of the line. This was causing an incorrect RAW file to be written. This has now been fixed.

August 26, 2016

Features and Improvements

  • File Formats: Fixed the reading of the ITEMS_LNAMP fields to appropriately set whether to monitor AMP limits
  • Power Flow Solution: SVC type switched shunts which had a minimum and maximum control range of 0.0 and 0.0 were being treated as though the control range was infinite (limits ignored). This has been changed so that the SVC will instead leave the min/max values as 0.0 and just never move instead.
  • Power Flow Solution: When opening an EPC file and solving the power flow immediately sometimes voltage controls such as tap ratios moved when it did not appear they needed to. The final solution still met the control requirements, but to the user it did not appear anything should move. This was caused when an svsmo1 or svsmo3 type SVC was initially at one of its maximum or mininimum control limits. The initial power flow solution was not properly catching when the SVC started at one of its control limits. This was causing the SVC to initially move to regulate voltage in the inner power flow solution (treated as PV bus). Then in the voltage control loop the SVC would realize it was at a limit and properly enforce the limit. While this was silly, the SVC itself ended up where it should. However moving of the system around may cause other voltage controls such as transformer tap ratios to change during the initial inner power flow solution and then move again after the SVC limit was enforced. All this moving around could give you a slightly different solution than expected. This has been fixed.
  • User Interface Dialogs: When defining a very large number of Transfer Directions for use in the multi-direction PTDF calculation, Simulator makes a new field available on a branch (and interface) for every transfer direction. When building a TreeView or a drop-down box in the user interface for choosing a field however this could make for a huge number of entries making the user interface extremely slow. One user reported waiting a couple minutes for the Model Explorer to open. This was due to about 24,000 transfer directions being defined. To fix this, TreeViews and drop-down boxes will never show more than 1000 of these dynamically created fields. A user may still use these fields using Auxiliary File scripting as well as via SimAuto, but they will not see them in the field choosers in the user interface. Note that these fields are already automatically added to tables where appropriate (like on the Multi-Direction PTDF calculation table). This change will also improve performance when viewing a list of fields if Multi-Element TLR calculations have been done with more than 1000 elements.
  • Bug Fixes

    • File Formats: When loading an EPC file, we now automatically use the advanced solution option to "Model Phase Shifters as Discrete Controls" as this represents how EPC files treat phase shifters.
    • File Formats: When loading an RAW file, we now automatically disable the advanced solution option to "Model Phase Shifters as Discrete Controls" as this represents how RAW files treat phase shifters.
    • Power Flow Solution: Discrete phase shifters with too narrow of a MW regulation range will often not move even when a control error still exists. This is because moving to the next tap settings will jump all the way across the MW regulation range and end up further away. Simulator has always written log messages about this, but they were repeated for every solution. The log has been changed so that this informational message is only written once now.
    • Transient Stability: Added the ability to look at the Area, Zone, Balancing Authority, Substation, and Owner information with all the various transient stability dynamic models.

August 25, 2016

Bug Fixes

  • File Formats: Fixed reading the ABB text file for setting tap min and tap max on three winding transformers

August 22, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Modified RestoreState script command to take optional parameter that can be USER, LASTSUCCESSFUL, or BEFOREFAILED. USER will restore the user specified state stored by the script command StoreState. LASTSUCCESSFUL will restore the state from the last successful power flow solution. BEFOREFAILED will restore the state before a failed power flow solution. This will work with power flow solved through the GUI or using the SolvePowerFlow script command.
  • Auxiliary Files (SCRIPT and DATA Sections): Added optional parameter with CTGSaveViolationMatrices script command to IncludeUnsolvableCTGs. Set this to YES to include unsolvable contingencies in the results and automatically include the Solved field.
  • Case Information Displays: Allow insert of a new Branch on the Transformer Controls table.
  • Contingency Analysis Tool: Added option with Contingency Violation Matrices to include unsolvable contingencies. When this is true the Solved field will be automatically added to the contingency matrix.
  • Contingency Analysis Tool: Multi-section lines are now supported by Custom Monitors.
  • File Formats: When loading RAW files, added option to specify a default switched shunt ID.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified the treatment of the @TIME and @DATE special strings when used in defining filenames in an auxiliary file. Previously
      @TIME would return the format "15:02:58"
      @DATE would return the format "April 12, 2016"
      This format is not appropriate for a filename however, so it will now return 150258 and 20160416 instead. This matches the format used with the @DATETIME string.
    • File Formats: Modified to write out the VECGRP as 12 blanks and CNXA as 0.000 for all transformers when writing to RAW version 33 or 34.
    • File Formats: When saving out to version 19 EPC file, two extra spaces were added to the beginning of some Long ID fields. This has been fixed.
    • File Formats: When reading hdbexport CSV files, added error checking so that if any NULL (00) ASCII characters are encountered while reading the file Simulator presents a dialog to Simulator to indicate that the file is corrupt.
    • General: Changed the numerical calculation of merging Multi-Section Line segments together to handle bypassed sections appropriately.
    • Power Flow Solution: Changes to SVC fixed shunt behavior.
    • Transient Stability: Modified the LD1PAC (and CMPLDW, CMPLDWNF for similar model) so that if the contactor model input parameters are inconsistent then the contactor model is ignored (Kcon=1 always). The check made is as follows.
      if (Vc1on < Vc1off) OR (Vc2on < Vc2off) OR (Vc1off <= Vc2off) OR (Vc1on <= Vc2on) then model is ignored.
    • Transient Stability: Changed so MotorW and MotorX models can support Lpp > Lp. This would occur with mimicking a PSSE CIM5 type 2 model, like those used in the CLOD.
    • Transient Stability: Minor bug fix to torque-speed curve calculations when the MVABase field is set.
    • Transient Stability: Fixed an access violation associated with moving fields in the Plot Designer tree view.
    • Transient Stability: There was a minor sign error in the overvoltage equation in svsmo3 transient model that was causing the shunt to operate immediately from the no contingency state. This has been fixed.
    • User Interface Dialogs: Modified the built-in Auxiliary File Export Format Description "Network Model" to include the substation field IDExtra.

August 11, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): When using the CTGSaveViolationMatrices script command, contingency names containing commas were not enclosed in double quotes so that they could be properly loaded in Excel. This has been fixed.
  • Difference Case Tool: Fixed comparison of the MTDCConverter Firing Angle in the Difference Case Tool.
  • File Formats: When loading in an EPC DC Converter record, the DC-side transformer taps were not being used appropriately. We now read the DC side tap and adjust the transformer ratio appropriately to model that effect. Also, when writing out the EPC file the DC-side taps are written back out as they were input and the DCBase is written appropriately.
  • File Formats: DC converters can have 2 sources of losses:
    1. Losses in the transformer, valves and auxiliaries that are proportional to the DC current (modeled as a commutating resistance Rc)
    2. Losses due to the voltage drop across the diode (modeled as a voltage drop)
    The RAW format supports the commutating resistance but not the Vdiode drop.
    The EPC format supports the Vdiode drop but not the commutating resistance.
    Simulator now supports both of these phenomena. When writing out to a RAW file, if the Vdiode term is non-zero then the Rc term is written increased by Vdiode/(2*DCCurrent) to represent the losses at the present operating point. When writing out to an EPC file, if the Rc term is non-zero then the Vdiode term is written increased by 2*Rc*DCCurrent.
  • Power Flow Solution: Augmented the modeling of DC Converter losses to allow the use of a Vdiode drop term as part of the converter model. This effects both the calculation of the DC voltage as well as adds an additional MW loss to each converter equal to the NumBridges * Vdiode * DCCurrent.
  • Power Flow Solution: Fixed the modeling of the DC Converter losses using the Commutating Resistance term. This was being properly modeled for the effect on the DC voltage, but the resulting MW losses were not being includied in the Power injection at each converter. This has been changed so that an additional MW loss is added to each converter equal to the NumBridges * 2 * Rcomm * sqr(DCCurrent).
  • Transient Stability: Corrected torque curve calculations for type 2 motors.
  • User Interface Dialogs: Modified dialogs and hints regarding the generator field "Enforce MW Limits" to make it clear that this only applies when the generator is being automatically controlled by the software. This limit is not immediately enforced and may not be enforced at all if the generator does not participate in control.

August 10, 2016

Features and Improvements

  • General: Implemented Merit Order Close injection group scaling option with Scale tool.
  • Transient Stability: Added Gen MVABase field to SMIB eigenvalue display.
  • Transient Stability: Added ability to read another PSS/E DYR Helper file for reading BAT_PLMOD_REMOVE commands to disable various dynamic models.
  • Transient Stability: Added parameters on transient stability dialog to specify minimum MW and P/Q ratios to use in complex load models.
  • Bug Fixes

    • Case Information Displays: When changing a data maintainer through the GUI, prevent a data maintainer from being assigned to a data maintainer if it will cause a circular reference.
    • File Formats: When loading RAW files, look for *! characters to indicate a comment in addition to /.
    • File Formats: When loading a RAW file, duplicate lines are now overwritten instead of creating duplicate lines.
    • General: Error messages could show up in the message log if an SVC and switched shunt on either discrete or continuous control are regulating the same bus. This is not an error; there was simply a problem with the message reporting. This problem has been fixed.
    • General: Various places in Simulator report the devices that are regulating a bus. SVCs were not being correctly shown in these places. This has been fixed.
    • Transient Stability: Fixed issue with WT3E and WT4E "exciters" in which Kiv and Kpv are both zero. This is actually OK if the control is not being used.
    • Transient Stability: Fixed parameter order with SWSHNT model.
    • Transient Stability: Bug fixes to UEL2_PTI model.
    • Transient Stability: Removed three load shedding parameters from the CLOD model.
    • Transient Stability: Fixed access violation associated with loading FACRI_SC model from aux file. This could occur if identifying the associated series capacitor by a multi-section line and section number.
    • Transient Stability: Fixed load relays so they don't trip if the bus is not inservice.

August 4, 2016

Features and Improvements

  • Available Transfer Capability (ATC) Tool: Added new Merit Order Close option for injection group ramping during iterated ATC methods.
  • PV and QV Curve (PVQV) Tool: Added new Merit Order Close option for injection group ramping with the PV tool.
  • Bug Fixes

    • Contingency Analysis: Corrected problem with seemingly random access violations occurring with running or examining contingencies.

August 3, 2016

Features and Improvements

  • Transient Stability: Added UEL2_PTI model.
  • Bug Fixes

    • Contingency Analysis: Made improvements to the options for storing contingency results to hard drive.
    • Contingency Analysis: Writing CTG What Actually Happened display setting to case (still saved to Registry as well).
    • Contingency Analysis: When comparing 2 lists of contingencies, violations which occur in the Comparison List but NOT in the Controlling list are show on the list of violation for a particular contingency. However, they were NOT shown in the list of all contingency violations. This has been fixed.
    • Contingency Analysis: When showing the Value, Limit, CompareValue, and CompareLimit fields for a contingency violation we had previously made it so that at a minimum 4 significant digits are always displayed regardless. We had also done the same for the difference fields which was silly. This made it so that a value of 567.1230001 subtracted from 567.1235555 would always show a difference of 0.0005554. We now obey the right of decimal designation of the user but make sure that how ever many digits are needed to display the Value or CompareValue to 4 signficant digits are also displayed for the difference.
    • File Formats: When loading an EPC file which has a maximum phase shifter of 0.0 degrees, Simulator was incorrectly turning the transformer off control. This was caused by a validation check made in October 2008 when loading an EPC file. In 2008, PowerWorld users had reported that when we reading an EPC, if a tap ratio that was more than 1/2 step size outside of the TapMin/TapMax range, Simulator should turn the transformer off control. This was done in 2008, but we were incorrectly checking the tap ratio for a type 4 EPC transformer. The bug that was just fixed has changed it so that this check is made with the transformer phase shift for type 4 transformers in the EPC file format.
    • General: If a bus record's nominal voltage is changed and this bus is the internal star bus of a three-winding transformer, then we will now automatically change the To-Bus Transformer Base Nominal Voltage of the 2-winding equivalents transformers to match this. This only effects the viewing of the 2-winding equivalent values on the transformer base and does not impact solutions.
    • General: Fixed a bug with DateTime advanced filter conditions, disallowing the form's DateTime pickers from being set to the null date.
    • General: Fixed 'div by zero' error that was being generated when trying to set an invalid value as a datetime.
    • General: Added a cancel button to the patch check so that users don't have to wait on startup. This is especially problematic when the computer Simulator is on doesn't have Internet access, typically leading to a two minute wait.
    • Transient Stability: Added check on ESST4B Vb making so it is always > 0.
    • Transient Stability: Fixed a bug in reading Switched Shunts from DYR files.
    • Transient Stability: Fixed bug in which the TS Bus and Gen displays had errors due to stale pointers.
    • Transient Stability: When showing a case information display showing the transient stability results related to a plot definition, the case info toolbar was always disabled. This has been fixed.
    • Transient Stability: Fixed undefined variable bug in LD1PAC Load Model that was causing the Jacobian to always be updated.
    • Transient Stability: An error could result indicating that no results were selected to save even if transformer fields were selected. This has been fixed.
    • User Interface Dialogs: In the advanced filter dialog when changing the Chosen Field from one field to another, we no longer update the comparison type if the comparison is available for both fields.

July 21, 2016

Features and Improvements

  • Case Information Displays: Modified how Simulator determines the tap integer position for transformers. Previously Simulator would treat the 0 position as the tap in the middle of the TapMax/TapMin range. This has been changes so that the 0 position is always represented by 1.0000 on the TRANSFORMER BASE. Positive tap positions then move upwards from there and negative tap positions move downwards from there.
  • Case Information Displays: Added the ability to edit the variable transformer tap ratio (or phase) by editing the Integer Tap Position directly instead of by editing the TapRatio or Phase.
  • Case Information Displays: Added new fields for Branch objects to show the Maximum Integer Tap Position and Minimum Integer Tap Position. These are calculated from the the TapMax and TapMin values (just as the TapMaxxfbase and TapMinxfbase are calculated). Also added the ability to edit these fields which will modify the TapMax and TapMin field as appropriate.
  • Case Information Displays: Added 2 new user-entered fields to a transformer for use in translating Simulator's integer tap position into an integer that uses the EMS convention. One field is TapPosEMSNom which specifies the integer considered to be at the nominal tap (1.0000 on transformer base or 0 degrees for a phase shifter). The second field is the TapPosEMSStepSign which is either +1 or -1.
    TapPosEMSStepSign = +1 indicates that a positive TapPosEMS means an increasing tap ratio going up to TapMax.
    TapPosEMSStepSign = -1 indicates that a positive TapPosEMS means a decreasing tap ratio going down to TapMin.
    The translation is as follows: TapPosEMS=TapPosEMSNom+(TapPosEMSNom*TapPosEMSStepSign)
  • Case Information Displays: Added a new field to show the integer tap position using the EMS convention. The tap or phase can then be edited using this field as well. The EMS convention uses the following conversion: TapPosEMS=TapPosEMSNom+(TapPos*TapPosEMSStepSign).
    When editing this field the Tap or Phase of the transformer will be edited as appropriate.
  • Case Information Displays: Added a new field to show the integer max tap position using the EMS convention.
    If TapPosEMSStepSign = +1, then TapPosEMSMin = TapPosEMSNom + TapPosMin.
    If TapPosEMSStepSign = -1, then TapPosEMSMin = TapPosEMSNom - TapPosMax.
    Notice that when TapPosEMSStepSign = -1 then TapPosEMSMin is related to TapPosMax.
    When editing this field the respective TapMin or TapMax are edited as appropriate.
  • Case Information Displays: Added a new field to show the integer min tap position using the EMS convention.
    If TapPosEMSStepSign = +1, then TapPosEMSMax = TapPosEMSNom + TapPosMax.
    If TapPosEMSStepSign = -1, then TapPosEMSMax = TapPosEMSNom - TapPosMin.
    Notice that when TapPosEMSStepSign = -1 then TapPosEMSMax is related to TapPosMin.
    When editing this field the respective TapMin or TapMax are edited as appropriate.
  • Bug Fixes

    • File Formats: Fixed how the maximum and minimum tap (ratio or phase) are read from the hdbexport CSV files. Note that the actual tap positions for phase/tap ratio were being read correctly and this only impacted the minimum and maximum tap ratios. See the explanations of the many new fields added as part of this patch for more information. Previously if the integer tap positions NOM_TAPTY was exactly in the middle of the MX_TAPTY and MN_TAPTY tap positions read from the CSV file, then the TapMax and TapMin were read correctly (this was true the vast majority of time).
    • File Formats: Fixed error when loading Generator Reactive Capability Curve data (*.gcp) files exported from PSS/E. Any quote characters were not being properly handled in this format.
    • Power Flow Solution: Modified how SVC control of fixed switched shunts is handled when the terminal voltage is extremely low (below 0.7)
    • Transient Stability: modified to read the BASEGEN PTI helper file for dynamics data from WECC. A newer version of this file supports entering the "baseload flag" as either 0, 1, or 2 in the same manner as it is listed int he EPC file. (0 = normal, 1 = Down Only, 2 = Fixed).

July 19, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a column to the Branch table of the Lines that Create Islands dialog to show a list of the buses islanded if the branch is open, as bus numbers separated by commas.
  • Case Information Displays: Added a column to the Branch table of the Lines that Create Islands dialog to show a list of the buses islanded if the branch is open, as bus numbers separated by commas.
  • Case Information Displays: Modified how the popup hints are displayed so that if the hint includes specified carriage return/line feeds it would not add unnecessary CRLF.
  • Contingency Analysis Tool: Added new features for specifying to store contingency results to hard drive while running large contingencies runs instead of storing the results in RAM as they are processed.
  • Difference Case Tool: modified Difference Case Tool so that the removed object types for Interface, InterfaceElement, LineShunt, 3WXFormer, and GenVarLim will properly obey the Area/Zone Filters.
  • Difference Case Tool: Modified the GenVarLim object to obey the Area/Zone/Owner filters
  • Transient Stability: Added a splitter on the various Stability tabs when showing the list of objects under the Parameters section for a stability model. Previously you could only see 2 objects at a time and had to scroll through all of them. Now you can move a splitter on the dialog to dedicate additional space to the list of objets under the parameter section.
  • Bug Fixes

    • Contingency Analysis: On the Contingency Violation Matrices dialog, the toolbar buttons were not properly updated as you clicked on the case information displays. This has been corrected.
    • File Formats: Modified so that when reading an EPC file if the load record has a ithrbus specified, but the ithflag <= 0, then we ignore the specified load throwover bus.
    • User Interface Dialogs: When right-clicking on either an individual interface element, or when choosing to create an interface that is the reverse of an existing interface, then the metered end of the branch was also being flipped resulting in a slight difference in flow due to losses. This has been modified so that the metered end remains consistent when reversing an interface element.

July 14, 2016

Features and Improvements

  • Difference Case Tool: Modified the base case fields for a bus related to gen/load/shunt summations so that they show a value of blank if no gen/load/shunt even exists at the bus. Previously they showed a value of 0.0.
  • Difference Case Tool: When saving case differences using the new Complete Method, made sure that if chosen the Area/Zone filters would be used for writing the NEW and BOTH objects.
  • File Formats: Modified so that when creating a generator from an AUX file we default the EnforceMWLimit field to YES. Previously it was defaulted to NO.
  • GIC: For GICs added DoShowDialog for lines from voltage input display.
  • Transient Stability: Added initial limit violation check on the ST6B exciter for the Ilr and Va limits.
  • Bug Fixes

    • Transient Stability: Fixed a bug in the rectangular zone relays.
    • Transient Stability: Fixed a bug in loading an aux file with more than one distrelay in a branch.
    • Transient Stability: Increased internal subinterval integration for the ESAC2A exciter when Ka/Ta is too larger.

July 13, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): added support for filtering across objecttypes for the BalancingAuthority objects. This impacts the following objects: Bus, Gen, Load, Shunt, Branch, DCTransmissionLine, VSCDCLine, Zone, Area, SuperArea, Substation, SuperBus, Subnet, ReactiveCapability, 3WXFormer, MultiSectionLine objects.
  • Case Information Displays: added support for filtering across objecttypes for the BalancingAuthority objects. This impacts the following objects: Bus, Gen, Load, Shunt, Branch, DCTransmissionLine, VSCDCLine, Zone, Area, SuperArea, Substation, SuperBus, Subnet, ReactiveCapability, 3WXFormer, MultiSectionLine objects.
  • Case Information Displays: Modified so that one can edit the intermediate bus numbers of MultiSectionLine objects while in Edit Mode directly on the fields shown the intermediate bus numbers on the MSLine case information display.
  • Difference Case Tool: Added support for Present Topological Differences from Base Case tool for Load Model Groups and VSC DC Lines. Also cleaned up some things with LimitSet and VoltageControlGroups.
  • Difference Case Tool: Added storage of RatingSetNameBranch, RatingSetNameBus, and RatingSetNameInterface to the Difference Case Tool.
  • Difference Case Tool: Also modified to ensure that all case information displays appear with a light yellow background when in Difference or Base Case Mode in the Difference Case Tool
  • File Formats: Modified to initialize the generator field EnforceMWLimits for all the various file types. Previously this was handled for RAW and EPC files, but it really needed to be handled for hdbexport CSV, MatPower, UCTE, Siemens, IPF etc. as well. Now after reading all non-PowerWorld file formats any generator that meets both of the following criteria will enforce be set to EnforceMWLimits = NO.
    1. Generator is online (both CLOSED and attached to a connected bus)
    2. Generator is more than 5 MWs outside of it's limits: [MW < (MWMin - 0.5] OR [MW > (MWMax + 0.5)]
    The thinking is that if the generator is clearly outside its limits then limit enforcement is not expected. The 0.5 MW tolerance is used to bias the decision to continue enforcing MW limits.
  • Transient Stability: Improving plotting Zone 1 in DistRelay.
  • Bug Fixes

    • Difference Case Tool: Fixed error in determining the difference for InterfaceElement's that refer to another interface and PartPoint's that refer to another InjectionGroup.
    • Transient Stability: Fixed bug with TGOV2 and TGOV3 in which the fastvalving function was continuing to increase.
    • Transient Stability: Fixed a bug in DistRelay when Rr = 0 it was not creating a zone to protect regardless that Wt was not zero.

July 8, 2016

Features and Improvements

  • Difference Case Tool: added support in LimitSet and VoltageControlGroup object differences to be shown in the Difference Case Tool
  • Difference Case Tool: Modified when loading a ReactiveCapability data section of an AUX file. If the required fields necessary to create a new ReactiveCapability objects are in the data section header, then upon reading a point for a particular generator, Simulator will first delete all existing points. The assumption is if you are editing any portion of the curve you are replacing all of it. If however, the fields necessary to create the ReactiveCapability are NOT present, then Simulator will simply look for the particular MW value of the Capability curve and edit the fields listed. There are really only 3 fields editable on this object (MvarMax, MvarMin, and Selected). If both MvarMax and MvarMin are present, the file will assume you are replacing the entire capability curve because those are the required fields. If however, only the Selected field is present we will assuming you are only selecting particular points, likely to be followed up by a Delete command.
  • Difference Case Tool: Added ability to use the Selected field of a ReactiveCapability object so that points can be deleted using a script
  • Difference Case Tool: Added support for the showing the differences in the ReactiveCapability curves in the Difference Case Tool.
  • File Formats: Added new field for storing the EMSPSID with a Branch object in Simulator. When reading PS records from the hdbexport format, this will store the ID field for the PS record associated with an XF record.
  • Bug Fixes

    • File Formats: Fixed error in reading DC bus data from an EPC when an extra blank string was inserted after the nominal kV field. This was causing the record to be read incorrectly such as assigning the DC bus to the incorrect Area and Zone. The symptom a user would notice is that the area tie-lines were incorrect causing the ACE for areas to be way off.
    • Power Flow Solution: Added some code to prevent controller oscillations associated with the SVC fixed shunt switching.
    • User Interface Dialogs: Modified some hints and labels on the Switched Shunt dialog to better explain SVC input fields.

July 6, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added MultiSectionLine objects to the Network Model Auxiliary File Export Format Description. While the use of these objects is discouraged support is needed in this format to maintain them when users do create them.
  • Auxiliary Files (SCRIPT and DATA Sections): For a MultisectionLine object, added new fields BusInt, BusInt:1, BusInt:2 ... BusInt:20 which list the intermediate buses of a multisection line. This permits the creation of multi-section lines with up to 21 intermediate buses (22 intermediate branches) without using the section.
  • Case Information Displays: For a MultisectionLine object, added new fields BusInt, BusInt:1, BusInt:2 ... BusInt:20 which list the intermediate buses of a multisection line. This permits the creation of multi-section lines with up to 21 intermediate buses (22 intermediate branches) without using the section.
  • Contingency Analysis Tool: When choosing to either Save Case or Save Case As, a check is now done to help ensure that a user does not save a Post-Contingency system state accidentally. The check evaluates the following three conditions.
    1. Contingency Analysis dialog is open
    2. The Contingency Reference State exists
    3. At least one system device status in the present system is different than the status in the Contingency Reference State.
    If all these conditions are met, then a dialog will appear asking the user to confirm that they want to save the case.
  • Difference Case Tool: Modified the default columns of the BOTH and NEW lists on the Present Topological Differences from Base Case tool so that they include Bus Name and Bus Nominal kV fields for viewing in the tables. While these fields are not be part of the "Network Model" Auxiliary File Export Format Description, they are helpful to see on the visual tables inside the user interface.

July 5, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added ability to edit the Star bus name, voltage magnitude, and voltage angle on the three-winding transformer record.
  • Auxiliary Files (SCRIPT and DATA Sections): In the built-in Network Model Auxiliary File Export Format Description, added field for the three-winding transformer for star bus Name, star bus per unit voltage magnitude and star bus voltage angle in degrees.
  • Auxiliary Files (SCRIPT and DATA Sections): Added a new field for a Branch called MeteredBus. This shows the same information as MeteredEnd bus instead you enter the number of the bus which is metered. This make coordination of field when reading/writing from an AUX file or another database easier because the order in which key fields are listed doesn't matter then. The existing field MeteredEnd will say FROM or TO, but this must be coordinated with the how the From/To bus of the branch are defined.
  • Case Information Displays: Added ability to edit the Star bus name, voltage magnitude, and voltage angle on the three-winding transformer record.
  • Difference Case Tool: Modified the Present Topological Differences from Base Case tool so that it can write out an AUX file that converts one case into another case by using the new built-in Network Model Auxiliary File Export Format Description
  • Difference Case Tool: Added the Impedance Correction tables to the BaseCase storage of the Difference Case Tool.
  • Difference Case Tool: Modified the case information displays for NEW and BOTH tables on the Present Topological Differences from Base Case tool to show the same fields as are written to the "Network Model" Auxiliary File Export Format Description.
  • Difference Case Tool: Modified the Present Topological Differences from Base Case Tool so that it does not consider the flipping of the from/to bus of an Area-To-Area tieline a DELETE and ADD of a object anywmore. Previously it did this to avoid the confusing treatment of the MeteredEnd field. There is now a new branch field MeteredBus which avoids this confusion.
  • File Formats: Sped up the the reading of hdbexport CSV files greatly. The parser in Version 19 is much more flexible for reading these files but it had made reading the files slow. This has been fixed so that it remains fast as it was in Version 18 but also flexible so we can add future fields easily.
  • Scheduled Actions: Allow scheduled actions to be identified by label in the scheduled action dialog.
  • Transient Stability: Added ability to store the GIC transformer nuetral current in transient stability.
  • Transient Stability: Improved network boundary equation solution for loads which use the Distribution Equivalent.
  • Transient Stability: Added a new script command TSAutoInsertZPOTT(reach, filtername); where reach is a number representing the per unit reach and of the zone 1 relays (0.8 to represent 80%) and filter name is the name of a filter describing which Branch objects upon which to add these relays. Note that the zone 2 reach is hard-coded as 1.2 (120%) for this command.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with the sorting of balancing authorities by name which would cause a balancing authority not to be found when setting an object's balancing authority by name even if the balancing authority was already created.
    • Power Flow Solution: Within a group of generators coordinating remote voltage regulation, it was possible for some of the generators to become stuck at their max or min var limit while the others continued to float between limits. This has been fixed.
    • Transient Stability: Fixed bug with PlayInGen machine model when the initial frequency was not nominal frequency (60 or 50 Hz typically).
    • Transient Stability: When running a transient stability simulation it was possible for the Selected Step TreeView on the left of the dialog to become out of sync with the dialog. This has been fixed.
    • User Interface Dialogs: Fixed an access violation that could occur when auto inserting injection groups with bus participation points.

June 24, 2016

Features and Improvements

  • Difference Case Tool: Modified to better handle comparing difference case tool for unlinked Interface Elements
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When finding an InterfaceElement while loading from an AUX file, if the interface element could not be found Simulator was still creating an empty interface. This has been fixed so that the Interface is only created if the InterfaceElement is created.
    • Auxiliary Files (SCRIPT and DATA Sections): The InterfaceElement object could not use the ObjectID field as a method of finding the object. Simulator has been augmented so that this field can be used for InterfaceElement objects.
    • Bus View and Substation View Onelines: When showing a Customized Bus View, the multi-section line fields were not customized and would always show MW, MVar and MVA in that order. Simulator will now show fields in the order the user specifies them in the customization, but will only show values for MW, Mvar, MVA, and Amp fields.
    • File Formats: Modified when writing out the EPC format to write disconnected bus as Type 0.
    • GIC: Fixed error when editing the field to signify that a user-entered DC resistance on a transformer coil should be used.
    • Optimal Power Flow (OPF): Fixed an index-out-of-range that could occur when running the OPF solution.
    • Power Flow Solution: Fixed an issue with svc control that under rare situation could cause an oscillation when switching fixed shunts.

June 20, 2016

Bug Fixes

  • File Formats: When loading in transformer records from a RAW file, there have been some instances of files where the impedance correction table entry is missing and causing the file load to fail. We now check and if there is no entry for this we just assume 0 and continue reading the file. Any fields that are supposed to appear on the same line after this are also assumed to be defaults.
  • Oneline Diagrams: When specifying default drawing values with a line stub length of zero and a stub spacing of zero, auto-inserted lines were being connected to the upper-left corner of substation display objects. This has been changed so that the lines are instead drawn to the center of the substation to match the behavior of bus display objects.
  • Scheduled Actions: Fixed a bug with Scheduled Actions where 0:00 times were being read in as 12:00

June 15, 2016

Bug Fixes

  • Scheduled Actions: Bug fixes for Scheduled Actions:
    - Mapped description fields are now read in correctly
    - Allow CSV files to load while open in other programs
    - Prevented default action from overwriting other mapped actions
    - Refresh Scheduled Action grids upon import completion
  • Security Constrained OPF (SCOPF) Tool: Fixed a "out of index" error message that could result when trying to solve the SCOPF.
  • Transient Stability: Modified the WTGTRQ_A model to multiply the output by speed to be consistent with implementation of other software.
  • Transient Stability: For the REEC_A model, using the PFlag = 1 while also using a torque controller (WTGTRQ_A) is not appropriate because multiplication by speed is already handled in the WTGTRQ_A model. Appropriate validation error messages have been added and auto correction to 0 have been added.

June 14, 2016

Features and Improvements

  • File Formats: Added log messages when reading an EPC file with ownership percentages of either zero or negative values are seen.
  • General: Modified to allow an owner percentage of zero (0). Previously we would completely remove this designation. Obviously we would not recommend doing this, but some users specify these percentages (likely accidentally) and wanted to be able to not completely lose the fact that the owner was a partial owner of the object.
  • Bug Fixes

    • Difference Case Tool: Interfaces that had no elements assigned to them were causing an access violation when using the option to Set Present as Base Case. This has been fixed.
    • File Formats: When loading in the IEEE common format, generators were not being created when loading Bus Data specifying Type 1. Generators will now be created with their AVR field set to NO. When loading in Branch Data with Type 1, transformers were not being created. Transformers are now created and set to Fixed.
    • Oneline Diagrams: Fixed a bug that could be introduced when copying objects within a oneline or from one oneline to another. If the file was then saved to PWD, extra entries could result in the file resulting in errors when trying to load the file again. The fix will ensure that the extra entries do not end up in the PWD file. PWD files with this problem can be read with manual intervention from PowerWorld staff.
    • Scheduled Actions: Bug fixes for the Scheduled Actions Import Settings dialog
      -- When editing an existing label format, the "Test" utility now remains available.
      -- When closing out from the label format dialog, label format dropdowns now retain their set values.
      -- When loading import settings from an AUX file, existing settings are now completely cleared to avoid duplication.
    • Transient Stability: Fixed a bug in the new REPC_B model so that when entering kw1, kw2, etc.. and kz1, kz2, etc.. parameters which were zero. If these values are zero, then the output of that path should always be constant.
    • Transient Stability: Fixed a bug with initializing the REEC_A, REEC_B, and REEC_C models in the following circumstances:
      1. Qflag = 0
      2. REGC_A model had Xe <> 0
      In this situation the Qext reference value was not being set properly.
    • Transient Stability: Fixed error in setting the initial pitch angle for WTGPT_A when the WTGAR_A model has a non-zero Theta0.
    • Transient Stability: When loading in a TSContingencyElement from an AUX file the actions for a generator for CHANGEBY Exciter_Setpoint and CHANGEBY Governor_Setpoint were not be read. This has been fixed.
    • Transient Stability: When using the script command TSGetResults, if any switchedshunt data was being stored the export was not working properly. This has been fixed.

June 8, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): added code for relay data import script commands: TSLoadRDB and TSLoadRelayCSV
  • Difference Case Tool: added support to the Difference Case Tool for showing differences in three-winding transformers
  • Difference Case Tool: added support to the Difference Case Tool for showing differences in balancing authorities
  • Difference Case Tool: added support to the Difference Case Tool for showing differences in MW transactions
  • Difference Case Tool: added support to the Difference Case Tool for showing differences in DataMaintainers
  • Difference Case Tool: added support to the Difference Case Tool for showing differences in Owners
  • Difference Case Tool: Added Difference Case Tool support for MTDCBus, MTDCLine, and MTDCConverter objects.
  • Difference Case Tool: Changed the Tree View list of objects on the Present Topological Differences from base case so that it has folders for Network and Aggregation objects. Also modified the Summary Table on this dialog so that it has tables for Network and Aggregation objects. These changes were made because of the large number of new objects now available for comparison in the difference case tool.
  • Bug Fixes

    • Contingency Analysis: The abort button will actually cause the contingency solution to abort if in the middle of the SOLUTIONFAIL step. Previously, if no solution was possible it would just continue until 100 iterations were reached.
    • General: When closing a case after defining supplemental data objects which contained other objects, an access violation could occur. This has been fixed.
    • Oneline Diagrams: When reading a KML diagram from ERCOT if a transmission line was encountered which did not exist in the power system case, an access violation occurred. This has been fixed so that instead the unlinked transmission line is created without an access violation occurring.
    • Oneline Diagrams: Fixed a problem reading a KML diagram from ERCOT. It was initially linking the power flow case transmission line to the display object, but when opening the dialog to show unlinked objects the lines would become unlinked.
    • PV and QV Curve (PVQV) Tool: Fixed an error with loading in the PVCurve_Options field RestoreState from an AUX file. This option was not being properly read in. The field is now named RestoreSystemState.
    • Scheduled Actions: Scheduled Actions bug fix -- Label Formats were not correctly handling lists of headers that include spaces.
    • Security Constrained OPF (SCOPF) Tool: In some situations a "grid index out of bounds" error could occur when attempting to solve the SCOPF solution. This has been fixed.

June 2, 2016

Features and Improvements

  • File Formats: Modified to read the DistMW, DistMvar and DistStatus fields from the EPC Version 19 files. Examples from users made it clear where these fields are at in the EPC data record.
  • GIC: Added ability to load the *.GIC format for GMD information used in PSS/E
  • GIC: Added field to show GIC substation electric field direction.
  • Bug Fixes

    • Transient Stability: modified to not popup error dialogs when validating user-written transient stability model DLLs
    • Transient Stability: Modified the svsmo1, svsmo2, and svsmo3 models so that if the slow B control is not active in the power flow input data, then we ignore the Vrefmax and Vrefmin values in the stability model. Vrefmax and Vrefmin are really part of the slow B control in the power flow, so if they're not active in the power flow model, it makes sense that they also not be active in the stability model.
    • Transient Stability: Simulator had previously been treating the input to PSS2B when code 3 used as as Pelec - PelecInitial. We have found that it is intended to be Pelec directly instead. This had never mattered previously because the first block on PSS2B was a washout block and thus any constant input offset was completely removed anyway. However, PSS2B has input limits Vs2max and Vs2min so this distinction would matter if these limits were specified. PowerWorld had never seen a model with input limits that would be active however, so this had never been noticed. This has now been fixed.

May 31, 2016

Features and Improvements

  • File Formats: When reading an EPC file, if the Sum of Ownership participation for an object sums to a value which is not 1.000 then Simulator will automatically scale the values so they do sum to 100%. Log messages have been added when summations are not near 1.000 to help flag potential discrepancies in the input data. If the summation is greater than 3.00 or less then 0.50 then a log message is written. Also, if the summation is 0.000 then a log message is not written because Simulator will then simply default the ownership based on the terminal buses of the device.
  • GIC: Added new fields for specifying DC GIC resistance for SwitchedShunt and LineShunt objects.
  • GIC: Added a new field for an extra transformer neutral resistance
  • Transient Stability: Added ability to specify any TSContingency object's variablename using a special string @CTGvariablename:digits:rod. This will be replaced with the value of that TSContingency field. The special string must start with @CTG and this then followed by the variablename and then optionally followed by syntax of :digits:rod to specify the number of digits and the number of decimal places to include. Example include the following
    1. @CTGCategory would add the Category string
    2. @CTGLoadMWIslanded:8:3 would add the LoadMWIslanded field with 8 digits and 3 decimal points
    3. @CTGGenMWTripped:6:2 would add the GenMWTripped field with 6 digits and 3 decimal points
    Previously this was limited to the values for @CTGMemo and @CTGName. This extends this syntax to all variablename of a TSContingency object.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When reading a MSLine record section from an AUX file, if the buses in the list could not be found no indication was given. This has been changed so that if a bus cannot be found it an appropriate error message is written to the log and the process continues
    • Auxiliary Files (SCRIPT and DATA Sections): When reading a MSLine record section from an AUX file, if the buses were listed in a reverse order (To bus toward the From Bus) then the MS Line record would abort reading the AUX file. This has been changed so that we instead create the MSline record and record the relevant reverse order in the log
    • Auxiliary Files (SCRIPT and DATA Sections): When reading a MS Line record section from an AUX file, if the list of buses did not successfully define a multi-section line record then the reading of the aux file would be aborted. This has been changed so that appropriate error messages are instead written but the aux file continues to read.
    • File Formats: When writing out a generator with AVR=NO to an EPC file, in older versions of the EPC format one had to write out the Max/Min Mvar equal to the present Mvar. Starting with EPC version 18 it was possible to write out a flag indicating a fixed Mvar output, however PowerWorld was still change the Min/Max Mvar when writing out the generator records. This has been changed so that the Max/Min Mvars are written appropriately to the EPC format.

May 26, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added ability to edit the Star Bus Number of a three-winding transformer while in edit mode. This has the effect of renumbering the star bus.
  • Case Information Displays: Added ability to edit the Star Bus Number of a three-winding transformer while in edit mode. This has the effect of renumbering the star bus.
  • Difference Case Tool: Added ability to differences in TLineShunts objects in the difference flows. This includes the topological differences of new and removed LineShunts.
  • File Formats: Added additional generator unit type codes of W1, W2, W3, and W4. These are useful for those building WECC base cases to match the designation used there to distinguish between Type 1, 2, 3, and 4 wind turbines.
  • Transient Stability: Added the original Contingency name into the convert Contingency into TSContingency. It eliminates a TScontingency if the name already exists and creates a new one, if do not exists just creates and add the new one with the original name.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified to add a message log error entry when reading in a ModelFilterCondition which refers to a Criteria which does not exist.
    • Available Transfer Capability (ATC) Tool: When running multiple scenarios ATC tool and viewing the transfer limiters case info display, an access violation could result when closing Simulator and an instance of Simulator could still continue to show up in the Task Manager. Both of these problems have been fixed.
    • Transient Stability: When initializing the Distribution Equivalent model in transient stability with an Mbase value that is zero or negative, the assumed MVABase is proportional to the MW of the Load. Previously we based this on the NetMW value of the load (difference between load MW and distributed generation MW). This has been changed so that the transformer and feeder impedances are instead proportional only the Load MW portion.
    • Transient Stability: When deleting a TSPlayin, if the PlayIn was referred to by a PlotSeries in transient stability, then an access violation could occur. Now after deleting a TSPlayIn object Simulator will automatically remove references to it from any PlotSeries.
    • User Interface Dialogs: Changed Logic Visualization Method to fix access violation that was happening when the screen was refreshed after clicking on a logic gate.

May 19, 2016

Features and Improvements

  • Contingency Analysis Tool: Added Area, Zone and Balancing Authority fields to Contingency Elements and increased the numbers to include up to 8 of them instead of 4.
  • General: Adding support for filtering on DateTime fields.
  • Optimal Power Flow (OPF): Added OPF option to "Include only online devices in Injection Group calculation". The default behavior has always been to exclude offline devices. This option will allow you to include them.
  • Scheduled Actions: Added field for the Duration of a Scheduled Action.
  • Transient Stability: Added Area, Zone, Owners and Balancing Authority fields to Transient contingency and elements.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: When using one of the iterated ATC methods, if the full transfer stepsize cannot be achieved during the part of the process where the transfer is actually implemented, the stepsize will be reduced by half until a solution is achieved or the stepsize falls below a tolerance. Previously, this tolerance was 10 times the MVA convergence tolerance. This could result in a very small tolerance and cause excessive iterations if no solution can be achieved. The tolerance for this process will now be the user defined Transfer Tolerance. This is a more reasonable tolerance and will make this part of the process consistent with the determination of acceptable stepsizes from the linear calculation.
    • File Formats: When writing the special object identifier for a branch that is part of a multi-section line to identify it by the multi-section line terminal buses and section number instead of any dummy buses, use the circuit ID of the multi-section line instead of the line section. The circuit IDs can be different. Apparently, when the & is included in a RAW file for the multi-section line circuit IDs, the line sections cannot include the &.
    • Power Flow Solution: Fixed a bug that would cause switched shunts not to move at a bus if a bus contains more than one shunt and the first one found has Auto Control = NO even though it has a valid control mode for automatic switching.
    • Transient Stability: Fixed some bugs with the initialization of the SVSMO2 model and setting the output of the SVC to a very low MVar value.
    • User Interface Dialogs: The Auto Control field is now enabled on switched shunt dialogs.

May 11, 2016

Features and Improvements

  • File Formats: Added code to set the PowerWorld series capacitor flag based on the SERDEV field in the Areva files.
  • User Interface Dialogs: Added button to Options drop down in Case Information Toolbar for "Show Column Metrics as Hints"
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that would always set the Initial Value field to SPECIFIED if creating PartPoint objects from a auxiliary file.
    • Case Information Displays: Added a fix to case information cell selection when a selection is already made but you select a different cell without dragging. The selection could end up moving incorrectly.
    • Contingency Analysis: Set the bus topology at the beginning of the Create Expanded Breaker Contingencies process from either the GUI or script command to allow users to change breakers at will to determine breakers required for a new topology without having to solve a power flow that might not solve.
    • Difference Case Tool: Show a value for Bus Nominal Voltage when showing the Difference Flows difference case for buses that are new in the present case and didn't exist in the base case.
    • Fault Analysis: Fixed a bug when building the positive and negative sequence admittance matrices. If there were 2 or more parallel transformers in the model, the off-diagonal elements in the admittance matrices were not correctly combining all of the transformer admittances, but rather was only putting one of the transformer admittances in the off-diagonal and was ignoring the rest of the parallel transformers.
    • File Formats: Modified reading of Areva hdbexport CSV file so that it automatically fixes problems with a CSV file if a user has read the file into Microsoft Excel and then saved as a CSV from Excel. Excel breaks the file format by appending additional commas at the end of the header text lines. In addition, any TAB characters at the start of the heading text lines become enclosed in double quotes breaking the format. Simulator now automatically detects these errors in the header and ignores the extraneous text.
    • General: Fixed a bug where the third winding of a three winding transformer was being accessed without first checking the make sure the equivalent transformer representing it existed.
    • Transient Stability: Modified loading of DYD file so that when reading an exciter, governor, stabilizer or machine model for a generator it will automatically make the last model read the active model. Previous the first model read was the active model.
    • Transient Stability: Transient stability now updates the display only after 100 milliseconds to run faster on small cases.

May 9, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command DeleteDevice("ObjectIDString");
    Examples would be
    DeleteDevice("Bus 234891");
    DeleteDevice("Branch 1239 1232 'AB'");
    DeleteDevice("Interface 'my interface name'");
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When using SaveDataEPC script command and appending a file, an extra blank line would be written to the file. This has been removed.
    • Auxiliary Files (SCRIPT and DATA Sections): An access violation could result if loading an auxiliary file containing fields referencing invalid location numbers, i.e. the number after the colon following a variable name. This has been fixed.
    • Difference Case Tool: Revisited the Base Case Topological Differences Dialog to use a Tree View listing of the various tabs instead of the Page Control. Also modified show show gray text for tabs which have nothing in them. In the summary modified it so that 0s are not shown instead a blank is shown.
    • File Formats: When appending an EPC file, line shunts within multi-section lines could not be found even if they existed in the case. This has been fixed.
    • Power Flow Solution: In places where switched shunts should be off control, instead of setting the control mode to Fixed the AutoShunt property is now set to NO. This will enable us to retain the appropriate type of shunt but still turn control off.
    • Transient Stability: Fixed some issues with the SMIB calculations. Including:
      (1) Calculations with GENTPF generators with saturation
      (2) Better handle algebraic models
      (3) Storing the machine G and B values
    • Transient Stability: When a negative ThetaMin value is specified for wind pitch controller WT3P, WT3P1, or WTGPT_A model, this can be used by the WT3T/WT3T1/WTGT_A model to determine it's Theta0 value. In this situation however, the initial output of the WT3P/WT3P1/WTGPT_A model could be either ThetaMin or 0.0 (zero). Both will result in the appropriate initial output from the Aerodynamic model. Previously Simulator was initializing this value to ThetaMin which appeared OK, but this equilibrium point is an unstable equalibrium. Simulator has been changed so that when ThetaMin is negative, the initialized output of the pitch controller is set to 0.0 (zero).

May 3, 2016

Features and Improvements

  • Contingency Analysis Tool: Added new contingency action to open elements in an interface in merit order by using SETTO or CHANGEBY actions.
  • Difference Case Tool: Added ability to the Difference Flows tool to show the added and removed InterfaceElement objects.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Line Shunts could not be deleted via auxiliary files. This has been fixed.
    • File Formats: Fixed a bug where EPC Modification Status for line shunts was not being populated when appending an EPC file.
    • Power Flow Solution: When validating discrete switched shunts, Vhigh must be greater than Vlow. If not, we had previously been setting the control mode for these shunts to fixed. Now the control mode will stay discrete, but the Auto Control field for the shunt will be set to NO.
    • Transient Stability: Minor change to PWFluxDecay model for speed dependence in swing equation.
    • Transient Stability: Fixed bug in which stabilizer speed inputs were not being handled correctly in the SMIB when the speed passed through the stabilizer. This fixed about 1/3 of WECC SMIB results with positive eigenvalues.

April 29, 2016

Bug Fixes

  • Contingency Analysis: Changed the contingency finishing status to show the number of custom monitor violations as well.
  • Distributed Computation: Fixed a bug that would not properly apply transformer filters with contingency Custom Monitors when using Distributed Computing.
  • File Formats: In RAW files there is a NAME field with transformers that we now store and make available with transformer objects. For three-winding transformers, the Name will be stored with the primary winding two-winding transformer.

April 28, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added optional parameter, Delimiter, to specify the file delimiter for both the Renumber3WFormerStarBuses("filename", Delimiter) and RenumberMSLineDummyBuses("filename", Delimiter) script commands. Options are COMMA,SPACE, or BOTH. If not specified then BOTH is assumed. The file delimiter can now be specified on the dialog that allows you to renumber multi-section line dummy buses or three-winding transformer star buses.
  • Case Information Displays: Added the ability to turn on hints on Case Info Displays that display column metrics for selected cells. Settings for these hints are on the Case Information Display tab of the Simulator Options dialog.
  • Difference Case Tool: Added ability to see which PartPoint objects are added/removed when using the present topological differences from base case tool.
    Also added ability to see changes in the PartPoint parameters between cases.
  • Transient Stability: Modified the PIDGOV governor model to return an initial limit violation of the final point on the non-linear Gate versus Power lookup function (P3) was a power that was less than the initial mechanical power.
  • Transient Stability: Modified the PIDGOV, WPIDHY, IEEEG1, IEEEG3_GE, TGov3, WSIEG1, URGS3T, WSHYDD, WSHYGP, G2WSCC, GPWSCC, GAST_GE governor models so that when setting the option of "Handling of Initial Limit Violations" to "Modify Limits and Run", Simulator will modify the final value of the nonlinear gain input curve if the initial output of the block is larger than the final value of the nonlinear gain.
  • Transient Stability: When reading the PIDGOV model from a DYD file, modified to ignore the MWCap value in the DYD file if it is different than the generator MVABase. The MWCap value is not used by PSLF or PSSE for this model and a value of MVABase is always assumed in those software tools. To be consistent with how the DYD format expresses the PIDGOV parameters, when reading a PIDGOV model Simulator will now always set the TRate value equal to the generator MVABase.
  • User Interface Dialogs: Fixed a bug on the Transformer Control Options dialog which was causing the regulated Max and Min values to be flipped.
  • Bug Fixes

    • Contingency Analysis: On the Contingency Specific Solutions Options dialog, two check boxes where not allowing you to click on them to revert them back to the "Use Default" options. These check boxes were the "Disable SVC Control" and the "Disable Treating Continuous SSs as PV Buses". This has been fixed.
    • Distributed Computation: Fixing some small memory leaks and also a problem where Simulator hangs when closing after certain large distributed runs.
    • File Formats: Fixed an access violation that could result when saving a PWB file with transformers that had been loaded from an EPC file.
    • Oneline Diagrams: Fixed a bug in specifying the the output of the Area record's slack generator MW using a Generic Model Field on a oneline.
    • Power Flow Solution: Made some corrections to how line drop compensation is implemented during contingency analysis.
    • Power Flow Solution: Corrected the logic when switched shunts are moved as part of the voltage control loop with the power flow solution. This shouldn't have caused any issues other than maybe causing additional voltage control loop iterations when Voltage Control Groups exist and the shunts in them are being changed.
    • Power Flow Solution: Fixed a very obscure bug that would only occur when two Continuous SwitchedShunt objects has different regulated buses AND those regulated buses were connected by very low impedance branches. In this situation the switched shunt control might result in one shunt moving slow upward and the other moving slowing downward until either the solution ran out of Voltage Control Loop iterations or one of the shunts hit a maximum or minimum Mvar limit. Simulator has been modified so that in situations like this the the switched shunts' control algorithms do not fight against one another. This was first seen in a WECC case (26HW1ae.epc) with switched shunts at bus number 56485 and 54159.
    • Simulator Automation Server (SimAuto): Return error messages in SimAuto if using ProcessAuxFile or LoadAux with RunScriptCommand.
    • Transient Stability: The option to Abort the simulation if any initial limit violations exist was not working properly. This has been fixed.

April 21, 2016

Features and Improvements

  • Case Information Displays: Allow pasting from Excel into the Limit Groups case information display.
  • Difference Case Tool: Added Use Capability Curve field for generators to difference flows comparison.
  • Bug Fixes

    • Difference Case Tool: Fixed some access violations that could result when showing the difference flows base case or difference case for the minimum/maximum continous Mvar or the Target voltage fields for switched shunts.
    • Fault Analysis: Fixed bug in the table listing multiple steady state faults which prevented the user from editing the fault impedance of the fault in that table.
    • General: Fixed problem with the colored lines on the left of the message log slowing filling up the entire log. This only occurred when using the special Solve Power Flow contingency element actions AND also using the TOPOLOGYCHECK actions. This had no effect on the calculations but only the visual display of the message log.
    • Transient Stability: When right clicking on a case information display on the Transient Stability dialog and choose Toggle All, the choices for toggle all were not properly shown. The would appear after clicking a second time on the particular data grid. This has been fixed so that the toggle choices appear the first time you click on the data grid.

April 19, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with the ReassignIDs(objecttype, field, filter, UseRight) script command so that the UseRight parameter actually works.
  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug saving out aux files with objects using three-winding transformers that do not have a tertiary winding.
  • General: Fixed calculation of integer tap position field for phase shifter. It was being calculated based on transformer tap instead of phase.
  • Integrated Topology Processing (ITP): Fixed error when saving a Consolidated Case if switched shunts were modeled across open breakers. Simulator now automatically moves these shunts across the open breaker to be grouped with other shunts on the same Superbus, however these shunts were not being properly set to Status=OPEN when doing this.
  • Transient Stability: Added ability to read/write the REPC_B model from the DYD file format.

April 15, 2016

Features and Improvements

  • Contingency Analysis Tool: Added option to include combinations of buses when auto inserting contingencies.
  • General: Added transformer regulated bus, switched shunt regulated bus, transformer type, and branch bypass fields to difference flows.
  • General: Added generator Unit Type to difference flows comparison.
  • User Interface Dialogs: Moved the Contingency Analysis folder in the Model Explorer UP a level to the main level. Previously it was inside the "Tools and Add Ons" folder.
  • User Interface Dialogs: Added a "RAS + CTG Case Info" drop down menu to the Tools Ribbon Tab next to the Contingency Analysis button. This gives more prominent and direct access to the various features related to Remedial Actions and Contingencies.
  • Bug Fixes

    • Fault Analysis: Fixed behavior of Fault Analysis window; it now opens in the same location it was closed in.
    • Fault Analysis: The main Simulator form would gradually keep shrinking each time Simulator was opened if the form was not maximized or resized. This has been fixed.
    • Transient Stability: Fixed error in ZPOTT when using the nfar bus which was not one of the terminals of the branch to which the relay was attached. It was not properly opening the branch at the far end bus when tripping.
    • Transient Stability: Modified ZPOTT and ZDCB so that if either Zone1 chooses to trip it will automatically trip the other end as well to implement the transfer trip.

April 8, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Allow RenameFile and CopyFile script commands to use the action and other keywords when specifying file names.
  • Contingency Analysis Tool: When saving an AUX file from the Contingency dialog there is another new checkbox to "Save Calculated Fields and Custom Expressions"
  • Model Explorer: Moved the Contingency Analysis folder in the Model Explorer UP a level to the main level. Previously it was inside the "Tools and Add Ons" folder.
  • Bug Fixes

    • Contingency Analysis: Custom Monitors monitoring fields that are part of contingency results (fields for a Contingency object such as total load or generation drop) might not show correct results if running contingency analysis multiple times. This has been corrected.
    • Contingency Analysis: Fixed a bug that caused the field Solved for a contingency object to be improperly changed to YES when reading a ViolationCTG objects from an AUX file. This also occurred when passing results back to the main Simulator instance when using Distributed Computing for contingency analysis. This was improper because if the Solved field was equal to RESERVE LIMITS then you can still have ViolationCTGs reported, so reading the ViolationCTG objects should not change the Solved field from RESERVE LIMITS to YES.
    • Distributed Computation: Fixed an access violation that might occur at the very end of a Distributed Transient Stability Run
    • File Formats: When saving EPC snippets by selecting objects from a case information display or using the SaveDataEPC script command, bus objects will no longer be stored with branches. The bus records are beings stored for the Vsched field and this isn't used with branch or transformer records.
    • Power Flow Solution: Modified so that after loading a case any SVCs (svsmo1 and svsmo3) which are on continously control are appropriately denoted as being at a limit if this is appropriate. This prevents the SVC from being treated as not at the limit at the beginning of the power flow solution, moving a bit, hitting the limit and settling back in right where they started.
    • Power Flow Solution: Fixed small movements of switched shunt SVCs set on slow B control. Repeated power flow solutions would move around slightly within the slow B rectangular control region when it should just stay put once it is inside the control region.
    • Power Flow Solution: When a Switched Shunt was either an svsmo1 or svsmo3 SVC model type, the power flow solution internally treats a bus as a PV bus. During the solution the switched shunt Nominal Mvar output is then updated. This was all handled properly during the solution so power flow solutions were correct. However when just looking at the Mismatch table after a solution was achieved a mismatch may incorrectly be shown at these buses. This was purely a cosmetic bug because during the actual solution the mismatch was properly being treated as zero, but it was confusing.
    • Power Flow Solution: Modified so that immediately after loading in a case the proper mismatch would be calculated for buses that had more than one generator at them and some generators were at a min/max limit while other generators were not at a limit. As soon as a solution was done the mismatch calculation was immediately corrected previously, so this did not impact the solution, but it was confusing when loading in a PWB file to see initial mismatches when there should be none.
    • Transient Stability: If a CIM5 or CIM6 motor model was 0.0 MW in the power flow model and was out-of-service, then the CIM5 or CIM6 dynamic models would not being used because the load model was 0.0 MW (too small). For the CIM5 and CIM6 models however the Tnom value specifies what the torque is after being reclosed so the check on being a very small load is not appropriate. This has been fixed so the modeling of the closing of motor loads in this situation is properly allowed.
    • Transient Stability: Fixed an access violation that would occur when trying to insert a new Transient Limit Monitor from the Transient Limit Monitor table in the GUI.
    • Transient Stability: Modified the BRAKE load characteristic model to properly validate when used with a Bus, Zone, Owner, Area, or the case. The validation checks to ensure that the load was open in the power flow model were not working properly if the BRAKE model was not assigned directly to a load record.
    • Transient Stability: When choosing to save, copy, or print a transient stability plot with a very large number of plot series (1,000s or more), it would take a very long time to complete and may fail silently. This has been fixed so it performs very quickly and does not fail.
    • Transient Stability: For REEC_A, REEC_B, and REEC_C models, fixed error in the initialization of these models when Kqi=0 or Kvi=0. This was causing some incorrect initial state values.
    • User Interface Dialogs: On the transformer control information dialog the Min and Max regulated values had been flipped. This has been corrected.

April 1, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command SaveDataEPC("filename", objecttype, filter, GEFileType, SaveBuses, AppendFile).
  • General: Added options to filter by "string contains", "not string contains", "string starts with", and "not string starts with" for numeric fields.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Added new parameters UseAreaZoneFilters, AssumeBaseFiltersNotPresent, and AppendFile to the script command DiffFlowWriteRemovedEPC("filename", GEFileType, UseAreaZoneFilters, AssumeBaseFiltersNotPresent, AppendFile).
    • Auxiliary Files (SCRIPT and DATA Sections): When saving injection groups to an aux file, including SUBDATA for participation points, and saving by label, the points were being saved by bus labels instead of the object labels. This has been fixed.
    • Contingency Analysis: Fixed bug that would cause Solve Power Flow contingency actions to be converted to unlinked actions.
    • File Formats: Added reading MBS (Modify Bus Shunt) and SVD command to Disconnect or Reconnect a Switched Shunt in WECC switch files.
    • File Formats: Fixed a bug that would cause 0 load IDs when loading in an Areva hdbexport file.
    • File Formats: Fixed bug specifying limit groups and ratings when reading XFLIM, LNLIM, and ZBLIM records in an Areva hdbexport file.
    • File Formats: Fixed error with reading in Areva hdbexport file when fields were omitted from the file. We were not properly setting the default value for various fields in this situation.
    • General: When using the scale tool on injection groups and more than one injection group is selected for scaling, you will be prevented from scaling if using the option to scale from zero or using economic merit order dispatch. In this situation you can only scale one injection group at a time. Additionally, you would be prevented from scaling multiple injection groups at the same time if the starting MW or Mvar is 0. Preventing scaling if the original Mvar = 0 doesn't make sense if the injection groups only contain generators so this restriction has been lifted.
    • Transient Stability: Modified so that difference flows works with Synchronous Machine parameters. Previously it worked fine with transient stability generator-based objects except for with GENROU, GENSAL, GENCLS, GENTPJ, GENPTF. It now also works with the synchronous machine parameters.
    • Transient Stability: Modified reading of EPC/DYD file pairs in the treatment of reading the CMPLDW models. We now use the full "longID" field from the EPC file to create grouping so CMPLDW parameters that are unique. This then created appropriate names for the resulting Load Model Groups and Distribution Equivalents within PowerWorld Simulator.
    • User Interface Dialogs: Fixed access violation showing the Model Condition form if the filter has not been assigned.

March 23, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with Evaluate in Ref option not being saved to auxiliary file with Model Condition Conditions.
  • Contingency Analysis: While saving out contingencies in .ctg, or .con file formats, file contents were in the right format, but the file extension was always .aux. Now it is corrected to save it with the chosen file extension.
  • PV and QV Curve (PVQV) Tool: Fixed access violation that could occur when running PV using a consolidated case and stopping if dV/dQ sensitivities become negative.
  • Transient Stability: Fixed a bug with the Transient Stability Toolbar caused by including the path name with the name of the file specified with the contour export options.

March 17, 2016

Features and Improvements

  • General: Added new bus field called "Slack Bus Priority" that is an integer value used when dynamically choosing a slack bus when no slack bus has been specified. If any bus within the island has a slack bus priority greater than zero, then only the set of buses with the highest slack bus priority will be eligible for selection as the slack bus. Within this set of buses, the same rules apply as used for the normal selection of a slack bus. See the help for more documentation on how a slack bus is chosen. Also, if any slack bus priority is greater than zero, Simulator will not require that a load exist in the island nor will it required an island have more than one bus.
  • Bug Fixes

    • File Formats: Now read the REFPRI_UN field with UN records to determine the slack bus priority used when automatically determining the system slack bus.
    • Oneline Diagrams: Include transformers in the objects displayed in the Objects Not On Oneline dialog.
    • Transient Stability: Added ability to create Transient Stability Models by using the ObjectID of the referred to object.
    • Transient Stability: Fixed error with showing an extra floating point parameter for the PV1G model.
    • Transient Stability: Fixed minor error with handling fields for HYST1, BPA_D, and BBSEX1 models.

March 15, 2016

Features and Improvements

  • General: Added Switched Shunt field for "AutoControl" which may be specified as either YES or NO to specify whether the shunt is allowed to be automatically controlled. This means that you no longer are required to set the Control Mode to FIXED to indicate that it can't be controlled.
  • Bug Fixes

    • Contingency Analysis: Fixed access violations that could occur when showing the Contingency Violation Matrices.
    • Distributed Computation: The Pause option has been eliminated from Distributed Contingency Analysis.
    • Oneline Diagrams: Fixed some bugs associated with the Geographic Data View Style dialog.
    • Power Flow Solution: Modified so that internally in Simulator we always use a ZBRThreshold that is 0.01% larger than the user entered. This way we ensure if they set a branch impedance "equal" to the ZBRThreshold then it will always be treated as at or below. This is an issue because the branch impedances are stored as single precision floats, so you just don't know if the value is going to be evaluate as 0.00029001 or 0.00028999 and this impacts the results we get for things like generator var sharing and transformer tap balancing. When we actually USE the threshold we'll multiply it by 1.0001. 0.00029000 * 1.0001 = 0.000290029 which will ensure that all branches entered AT the threshold are treated as at or below it!
    • Transient Stability: When saving plot options to a PWB file, the option for automatically saving plots to file was not being correctly stored. This has been fixed.
    • Transient Stability: Fixed error in showing warnings and error messages in validation for a Load Distribution equivalent Q/P ratio.
    • User Interface Dialogs: Modified to ensure that when choosing to load a file saved using the AUX network file type it will automatically ensure you go to Edit Mode when loading the case from the Recently Opened file list.

March 11, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Updated DiffFlowWriteRemovedEPC script command. Now allows GEFileType: DiffFlowWriteRemovedEPC("filename", GETypeFile);
  • Power Flow Solution: added Switched Shunt field for "AutoControl" which may be specified as either YES or NO to specify whether the shunt is allowed to be automatically controlled. This means that you no longer are required to set the Control Mode to FIXED to indicate that it can't be controlled.
  • Transient Stability: Modified so that when showing the Transient Limit Monitor Dialog we automatically show the Limit Duration in Cycles if it is with 0.02 cycles of being at an integer multiple of a cycle up to 60 cycles. Thus at 1, 2, 3, 4, ... 59, and 60 cycles. Also modified so that if we're within 0.02 cycles of being at 0.5, 1.5 and 2.5 cycles the dialog will show the Limit Duration in cycles. Otherwise, it will automatically show the dialog in seconds instead. Internally within Simulator, we store this value as a floating point number of seconds, but this makes it convenient for viewing on the dialog.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): fixed bug with entering DCLine EPC-related fields if an EPC file hadn't been read to start.
    • Auxiliary Files (SCRIPT and DATA Sections): Fixed error with creating a switched shunt that was an SVC of type SVSMO1 or SVSMO3. The shunt wasn't being properly initialized for solution when created using an AUX file.
    • Auxiliary Files (SCRIPT and DATA Sections): When creating a continuous switched shunt from an AUX file, we must initialize whether the shunt is at a high or low limit so that the initial guess regarding a PV or PQ bus in the power flow solution is consistent with the initial shunt's state.
    • General: Fixing a bug that caused SimAuto to not function propertly when using hardware keys.
    • GIC: added ability to save and load new options regarding hot spot simulation from GIC_options to an AUX file.
    • GIC: modified to be able to see additional fields for the GICXFormer object. The GIC Model Used Break Point and GIC Model Used Second Segment.
    • GIC: modified to gray out the text for the 3 GIC Model input parameters if the GIC Model Type is set to Default to make it clear those values aren't being used.

March 11, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed error with creating a switched shunt that was an SVC of type SVSMO1 or SVSMO3. The shunt wasn't being properly initialized for solution when created using an AUX file.
  • Auxiliary Files (SCRIPT and DATA Sections): When creating a continuous switched shunt from an AUX file, we must initialize whether the shunt is at a high or low limit so that the initial guess regarding a PV or PQ bus in the power flow solution is consistent with the initial shunt's state.
  • File Formats: Fixed bug with entering DCLine EPC-related fields if an EPC file hadn't been read to start.
  • GIC: Added support for additional GIC options in auxiliary files.
  • GIC: Added GIC Model Used Break Point and GIC Model Used Second Segment fields to the GIC dialog.
  • Transient Stability: Modified so that when showing the Transient Limit Monitor Dialog we automatically show the Limit Duration in Cycles if it is with 0.02 cycles of being at an integer multiple of a cycle up to 60 cycles. Thus at 1, 2, 3, 4, ... 59, and 60 cycles. Also modified so that if we're within 0.02 cycles of being at 0.5, 1.5 and 2.5 cycles the dialog will show the Limit Duration in cycles. Otherwise, it will automatically show the dialog in seconds instead. Internally within Simulator, we store this value as a floating point number of seconds, but this makes it convenient for viewing on the dialog.

March 10, 2016

Features and Improvements

  • File Formats: Updated contingency parsing.
    ENREDEF_CTG -> Areva flag for open with breakers
    ACTIVE_CTG -> Areva skip flag

    The ITEMS records correspond to the contingency analysis base case violation reporting options.
    #record ITEMS
    ,%SUBSCRIPT
    ,BCAVIOCR_ITEMS
    ,VCAVIOCR_ITEMS
    ,NCAVIOCR_ITEMS
    ,ICAVIOCR_ITEMS
  • GIC: modified captions for CoreType to remove some confusion. It's confusing because the "Core Type" is generally either "Core" or "Shell". The word Core appears in two places which is confusing.
  • Transient Stability: Added secondary filter objects TimePointResultEvent and TSLimitMonitorViolation to TSContingency.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): cleaning up DataMaintainerAssign values for ModelFilter, ModelCondition, BGCalculatedField objects. These were not properly showing this as an available field.

March 8, 2016

Features and Improvements

  • Transient Stability: When running a list of multiple contingencies, added a refresh of the case information display showing the Transient Contingencies after each simulation run.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fix so that any type of filter, i.e. SELECTED, AREAZONE, etc. can be used with the object filters for SetSelectedFromNetworkCut script command.
    • File Formats: When loading the PSLF switching file, there was a bug if the R and X was not specified in a Bus Fault. Now is set to solid fault and do not expect to read R and X.
    • General: Removing hardware key driver installation from the software installation executable. You must now install the hardware key software using the separately downloadable HASPUserSetup.exe. Depending on machine-dependent Windows Security settings the hardware key installer may not work install correctly and this was causing software installation failure even for users who did not want to use a hardware key (which is most users).
    • User Interface Dialogs: Fixed a bug showing the correct 3 winding transformer when showing a Model Condition that has already been created.

March 4, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added script command SetSelectedFromNetworkCut.
  • Auxiliary Files (SCRIPT and DATA Sections): Added script command InjectionGroupCreateFromSelection.
  • User Interface Dialogs: Added option on the Auxiliary Export Format Description dialog to create a description that fully describes the Network Model Input.
  • Bug Fixes

    • General: Modified Auxiliary File Export Format Description blocks so that they can refer to a simple Condition directly using a string instead of requiring the creation of an advanced filter by name and referring to the name. This works the same as the Criteria for a transient stability model.
    • General: The Balancing Authority Name field was not taking changes entered in an AUX file or via case information displays. This has been fixed.
    • Integrated Topology Processing (ITP): Fixing bug with shunt consolidation when saving a full topology case to a consolidated case. The voltage was not being set when closing a breaker (as part of closing a breaker and switching a shunt's status) so that it is detected by the consolidate shunt to blocks code. Now the voltage is set when the breaker is closed.
    • Integrated Topology Processing (ITP): Mvar output of shunts connected to open breakers was not set correctly after the consolidated case had been saved. This has been fixed.
    • Oneline Diagrams: Fixed a problem with the Find Object on Oneline (Pan/Zoom) dialog that prevented the ESC key from closing the dialog. Hitting the ESC key will pan/zoom to the last selected location.
    • Oneline Diagrams: Fixed a problem that would prompt the user to save a oneline diagram file even when there were no changes to the diagram.
    • Transient Stability: Fixed three distributed computing bugs with transient stability: (1) The transient contingency case information display was not being updated at the end of a Multiple Contingency run. (2) Not all violations were properly being reported after a distributed run. (3) When saving results to RAM, the remote results files were not being created properly.
    • Transient Stability: Fixed access violation when writing to DYR files.
    • User Interface Dialogs: Cleaned up the Auxiliary File Export Description dialog.

February 29, 2016

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added script command CTGSaveViolationMatrices.
  • Contingency Analysis Tool: Contingency Violation Matrices tables now allow access to the fields associated with the object type displayed in the row of the table.
  • File Formats: Added reading the ELIGIBLE field from the LNLIM, XFLIM, and ZBLIM records from the hdbexport file. If this field is not in the file or if it is TRUE then we set the Monitor field in Simulator to YES. If the ELIGIBLE field is in the file and FALSE then we set the Monitor field to NO.
  • General: Added fields for three-winding transformers to show MonitorPri, MonitorSec, MonitorTer, LimitSetPri, LimitSetSec, and LimitSetTer.
  • Transient Stability: Initial implementation of generator plant controller model REPC_B.
  • User Interface Dialogs: Documentation images of three-winding transformer base conversions are now shown on the three-winding transformer dialog.
  • User Interface Dialogs: Added new menu item under Onelines Ribbon Tab-->List Display to show the list of Geo Data View Styles.
  • Bug Fixes

    • General: Modified the Bypass field for a branch to be either YES or NO. Previously it would show "Bypassed" or "Not Bypassed" which was cumbersome
    • Oneline Diagrams: If opening multiple onelines containing the same Geo Data View Styles, the styles could become undefined causing access violations or geo data view objects not to display. This has been fixed.
    • Oneline Diagrams: GIC sparkline var loss values are now reported in Mvar rather than per unit.
    • Oneline Diagrams: When exporting a KML file, the bus name used is just the Name of the bus instead of the LongName field.
    • Simulator Automation Server (SimAuto): "ALL" busloc qualifier is now allowed for the GetParametersMultipleElement/FlatOutput/Rect functions.
    • Transient Stability: Fixed error in svsmo1 and svsmo2 when Kp > 0 and Ki > 0.
    • Transient Stability: Fixed some PI blocks error in parameters with the Kp/Ki term been in the wrong order. Affected models are svcals, svsmo3, UEL1 and UEL2.
    • Transient Stability: Fixed issues with enforcing field limits on SEXS_PTI and SEXS_GE.
    • Transient Stability: Added subintervals for SVSMO1, SVSMO2, and SVSMO3 if inv(Kp)*Ki > 1/(2*time step).

February 18, 2016

Features and Improvements

  • Oneline Diagrams: Added a dialog to show sparkline values.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When reading an AUX file that had a CoreType, IsAuto, GICModelTypem, or GICManualCoirR value for a transformer which was blank, an error would occur. This has been fixed.
    • Case Information Displays: When showing a list of Area/Zone/Sub/BalancingAuthority that are contained in an Injection Group, if a Load/Gen/Shunt belongs to a different Area/Zone/Sub/BA than the terminal bus of the Load/Gen/Shunt then the Injection Group field would list the terminal bus' Area/Zone/Sub/BA as part of the injection group. This has been changed so that only the Area/Zone/Sub/BA directly assigned to the Load/Gen/Shunt is shown.
    • Case Information Displays: Added new fields for a LineShunt object to show the nominal MW and Mvar values. Previously you were required to edit these values using per unit values which is different than for the Switched Shunt records. THe nominal MW and MVar fields will now be the ones shown by default instead of the per unit values.
    • Case Information Displays: Fixed bug with editing the Line Shunt table values. Previous patch was causing any edited value of the G or B shunt value to be off by a factor of 100. This bug was introduced in February 8, 2016 patch and is now fixed.
    • Case Information Displays: Fixed an infinite loop that occurs when showing the Custom Case Information.
    • Contingency Analysis: When using distribtued computing, the summary timing information is not populated and any existing timing information is cleared.
    • File Formats: The options on the TLR form to Include on AGCable Generators, Include only online devices in Injection Group calculation, and determine whether or not to clear or append results are now stored in PWB files.
    • File Formats: Modified so that the normal status for branch objects is not stored with the "EPC File" fields for a branch. We now populate Simulator's normal status field directly when reading the EPC format and also write out Simulator's normal status field.
    • File Formats: When saving out an EPC file after having the case start as an AUX or RAW file, in the branch and transformer tables extra owner fields were being written. This has been fixed. This would NOT impact saving out an EPC file saved as a PWB and written back out as an EPC, so this bug effects very few people.
    • File Formats: When saving out an EPC file after having the case start as an AUX or RAW file, the generator record turbine type was not being properly written.
    • File Formats: Fixed error in writing out magnetizing reactance for three-winding transformer to EPC file. It was not being scaled properly by the MVABase of the primary-secondary winding.
    • General: Modified so that you can edit all the winding control information for secondary and tertiary windings from a three-winding transformer record.
    • General: Modified so that when changing the nominal tap of 3-winding transformers it updates the tap appropriately.
    • General: Added new switched shunt fields in ContinuousMvarNomMin, ContinuousMvarNomMax, SVCMvarNomMaxSH, SVCMvarNomMinSH, SVCMvarNomMaxSB, SVCMvarNomMaxSB which show previously existing values in units of Nominal Mvar instead of per unit.
    • General: Added Subnet as an secondary filter class for buses, generators, loads, switched shunts, branches, 3-winding transformers, dc lines, areas, zones, and injection groups.
    • Oneline Diagrams: Fixed a problem where the Selectable in Edit Mode field wasn't showing by default in the Screen Layers case information display.
    • Oneline Diagrams: Fixed bug caused by trying to select a sparkline style without an associated oneline when setting up a Geo Data View.
    • Optimal Power Flow (OPF): Modified so that after calculating an OPF solution, any out-of-service buses are automatically populated with prices equal to the closest in-service bus (measured by the number of nodes away). If multiple in-services buses are the same distance away, the average of the closest bus prices are used.
    • Optimal Power Flow (OPF): Fixed an access violation that could occur when running OPF.
    • Power Flow Solution: Fixed bug that could cause SVSMO1 and SVSMO2 switched shunts to move when they should not.
    • Transient Stability: Added a rate limiter check to governor model HYGOV4.
    • Transient Stability: When in the middle of editing a float or integer value on the plot designer AND then switching to a different part of the plot it was possible for the value you had been editing (for example the vertical axis maximum) to then propogate to the new part of the plot you were navigating too. This has been fixed.
    • Transient Stability: Fixed an infinite loop that occurred when showing the Transient Model Summary case information display.
    • Transient Stability: Added storing switched shunt Mvar injection in results.
    • User Interface Dialogs: Modified the Switched Shunt dialog to show the continuous element in units of Nominal Mvar instead of per unit.
    • User Interface Dialogs: Modified the Switched Shunt dialog to show the SVC values in Nominal Mvar instead of per unit.
    • User Interface Dialogs: Fixed infinite loop in the Area Dialog and interacting with the MW Transactions table.

February 8, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Added field with Sim_Solution_Options to enable/disable DFACTs control globally.
  • Case Information Displays: Added fields for three-winding transformer to show the Nominal Voltages of the buses in the object.
  • Contingency Analysis: Access violations could occur if deleting three-winding transformers that are part of a contingency element. This has been fixed.
  • Contingency Analysis: If using a Persistent contingency action in which no action was actually done but the Model Criteria was true, the What Actually Occurred information could indicate that something did occur. This has been fixed.
  • Distributed Computation: Fixed the issue that prevents remote distributed processes from terminating properly.
  • Distributed Computation: Improved distributed contingency analysis result processing efficiency.
  • File Formats: The option to disable SVC control globally was not being saved to PWB files. This has been fixed.
  • File Formats: The option to disable DFACTs control globally was not being save to PWB files. This has been fixed.
  • File Formats: Fixed error setting generator statuses on buses that are categorized as load buses in the Bus section of the RAW file. Previously only the first generator at the bus was being properly identified at a load bus and set offline. But any other bus read at the same terminal bus would be treated as if it was being connected to a generator bus, regardless of the bus category in the RAW file, because after the first bus was connected there (even out of service) Simulator was treating the bus as a generator bus from that point forward. Now all generators inserted at a bus categorized as a Load bus will be inserted out of service.
  • Integrated Topology Processing (ITP): When saving a full topology model to a consolidated case, shunts that are connected to the same superbus by open breakers will be merged into a single shunt with blocks.
  • User Interface Dialogs: Completely modified the three-winding transformer dialog to make it function more like other dialogs in Simulator. Also modified so that creating a three-winding transformer is actually possible using that dialog.
  • User Interface Dialogs: On the Transformer Control dialog added a caption to indicate which base the taps are on.

February 1, 2016

Features and Improvements

  • Case Information Displays: Added new Interruptible field for loads. This is an information only field.
  • Case Information Displays: Added a new generator field "UnitTypeCode" that shows the two character code for the UnitType. The field is the same as UnitType, just shorter.
  • Oneline Diagrams: Added new dialog to show Objects Not on Oneline. This will display data objects that are not currently represented on the oneline. There is also an option to show objects that are NOT on the oneline that are connected to buses that ARE on the oneline.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): LimitA, B, and C are no longer required fields for an interface definition.
    • Auxiliary Files (SCRIPT and DATA Sections): Modified how CalculateTLRMultipleElement script command behaves when one of the branch is presently out of service or in a dead island. Previously it would cause the script command to return an error. Now it just returns zeros for all those values instead.
    • Case Information Displays: Model Expressions that link to many other model expressions can cause the display of case information displays for objects that use model expressions to be very slow. This includes Model Conditions, Model Filters, and Remedial Actions. This problem has been fixed.
    • Case Information Displays: The concise field for an interface called LimitMWA was not being shown properly and was showing LimitMWA:0. This has been fixed.
    • Case Information Displays: In Version 18 the voltage regfactor sharing parameter at each generator at a single bus was synchronized to be the same. In Version 19, the RegFactors can be different at each generator at a single bus. Modified the treatment of editing the generator RegFactor field so that when changing the value it does not automatically change the value at other generators at the same bus.
    • Case Information Displays: Added fields for three-winding transformers to edit the R, X, Gmag, Bmag values on the 3-winding transformer winding voltage bases and winding MVA bases.
    • Case Information Displays: Added support for editing the FixedTaps, Nominal voltages, and winding MVA Bases for 3-winding transformers and automatically pushing those changes to the 2-winding equivalent branches.
    • Case Information Displays: Modified transformer Branch records so that many fields associated with transformers can not be edited for the 2-winding equivalent branches of 3-winding transformers. This includes fields like the FixedTap or Nominal voltage at the internal star bus.
    • Distributed Computation: Fixed the issue with distributed contingency analysis taking forever to complete after a large run with lots of remote processes.
    • Distributed Computation: Fixed the issue with performing distributed runs from SimAuto.
    • File Formats: Cleaned up reading reading of 3-winding transformers records in an EPC file if the variable tap and the fixed tap on the primary winding were both not 1.0.
    • File Formats: When reading hdbexport files set load AGC flag based on BASEW comparison of LD record. If BASEW >= 0.5*W, set AGC false. In other words, if the base load is more than half the load value, it is turned off AGC.
    • User Interface Dialogs: When editing a generator and changing the remote regulation factor, Simulator was automatically setting all generators at the same bus to have the same remote regulation factor. This was required in Version 18 of Simulator, but in Version 19 we no longer require this, so this action on the dialog needed to be removed.

January 26, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Made the owner name the secondary key field for owners.
  • Auxiliary Files (SCRIPT and DATA Sections): Modified reading the objects that refer to a bus as a key field (Gen, Load, Shunt, LineShunt, Branch, DCTransmissionLine, MTDCConverter, DFACTS, 3WXformer, and GenVarLim) so that when parsing using primary keys, the string for the Bus Number will automatically search for Bus Name_NomkV or Bus label as well.
  • Auxiliary Files (SCRIPT and DATA Sections): Changed string for Transformer Target Type values to "Middle" and "Max/Min" instead of "Middle of Range" and "Max/Min of Range".
  • Contingency Analysis: Made some changes to reduce memory usage by case information displays on the contingency analysis dialog.
  • Fault Analysis: Ground impedance fields for branches are now stored in the PWB file.
  • File Formats: Fixing reading text files when loading files that contain invalid characters for the current Windows system locale. A dialog will be shown with the error message and line numbers are shown in the message log for the lines that contain bad characters.
  • File Formats: When reading in hdbexport files and the CID field is available for LD records, it will be used for load ID fields.
  • File Formats: Fixed access violation that could result when writing out sequence data in the PTI format.
  • General: Added 8 owners to the VSCDCLine object.
  • Memory: Made some changes to reduce memory usage.

January 20, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): In an auxiliary file, modified writing of Owner objects so that we do not always include the SUBDATA sections anymore
  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with SendToExcel script command.
  • Case Information Displays: DataMaintainerAssign field should have been available for a LimitSet but was not. This has been fixed.
  • Case Information Displays: Fixed bugs with inserting new MW Transactions for the case information display.
  • Case Information Displays: Modified the Branch AutoControl field for a phase shifting transformer branch to have choices YES, NO, and OPF. Previously the choice was "Yes (powerflow)" to indicate that this was controlled in the power flow solution during the OPF solution algorithm. Now Yes just means that.
  • Contingency Analysis: If a contingency that implements no actions follows a contingency that hit reserve limits, the contingency that implements no actions will have reserve limits reported with it as well because this flag was not getting reset. This has been fixed.
  • Fault Analysis: Fixed bug setting up positive and negative sequence admittance matrices for an IEC-909 or Flat Classical fault.
  • Fault Analysis: Fixed application of the correct units (pu or amps) on fields displaying fault currents on the oneline.
  • File Formats: When writing to EPC and RAW files and there are more than 11 points in an impedance correction table, the points need to be reduced so that there are only 11. This had been permanently changing the impedance correction tables instead of just temporarily during the file save process. This has been fixed.
  • File Formats: Made some modifications to reading RAW file that supports ERCOT MOD generated file that is being appended to another case. The file contained another comment symbol (@!) at the end of several lines. The first line (title) also was read entirely as a comment since it started with a /, which caused the case ID section to be read incorrectly, and the first bus in the bus list was lost. I changed it so that now the first three lines have to be the case ID section, with no comments at the beginning of the RAW file.
  • General: Fixed including area transactions as part of difference flows. You wouldn't get a difference if you set the difference flows base case and then opened a different case.
  • General: Removed some confusing messages in the log about switched shunts at the same bus having conflicting regulated buses. These messages could occur when one of the shunts was actually off control due to the area setting for switched shunt control. The problem was only with messages. The actual control of these devices was correct.
  • Oneline Diagrams: Generator rotor was always being filled in if the default drawing values were applied to an existing generator. This has been fixed.
  • Power Flow Solution: Fixed a bug with not using the correct minimum limit for SVC type SVSMO3. This bug was introduced in the Dec. 18, 2016 patch.
  • Power Flow Solution: When using the Fast Decoupled Power Flow, solution problems could exist or access violations could result due to generators switching between being on AVR control and not on AVR control. This has been fixed.
  • Power Flow Solution: Generators that are on line drop compensation control that are no longer able to maintain this control will switch to PQ buses. This could cause power flow solution problems if the mismatch calculations are not updated for the change from PV to PQ bus. This has been fixed.

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.

January 8, 2016

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Generator reactive capability curves will first be cleared for a particular generator if a new one is being loaded from an auxiliary file for that generator requiring that all curve points for a given generator must always be specified in an auxiliary file. Reactive capability curves can now be created while in Run mode.
  • Contingency Analysis: When using a Custom Monitor to return the number of elements in a contingency, zero was always being returned. This has been fixed.
  • General: The PowerWorld Simulator icon was missing from the pwrworld.exe file. This has been fixed.
  • Oneline Diagrams: On the Zoom, Pan, and Find Objects dialog the zoom and pan values will be applied when clicking the OK button.
  • Transient Stability: For transient stability model, fixed coordinated initialization of the Distribution Equivalent Model when both a Load Characteristic and a Load Distributed Generation Model exists.
  • User Interface Dialogs: Fixed an access violation that could occur when viewing the Case Comments.

January 6, 2016

Features and Improvements

  • Contingency Analysis Tool: When saving an auxiliary file from the Contingency Analysis dialog by using the Save button on the bottom of the dialog, the user is presented with a rather large dialog that allows specification of the various objects that should be included in the auxiliary file and the format of the file. There is now a button that will open a document posted on the PowerWorld website describing the RAS and contingency aux file format.
  • Contingency Analysis Tool: When running contingency analysis from the GUI and results already exist, the user will be prompted if all results should be cleared or only if the results for contingencies that are not skipped should be cleared.

    Added another optional parameter to CTGSolveAll script command called ClearAllResults that will accomplish the same prompting as what is done in the GUI. Script command is now CTGSolveAll(DoDistributed, ClearAllResults) with both parameters optional. ClearAllResults = YES by default.
  • General: Added 9 new Unit Types based on updated DOE FORM EIA-860. New options are:
    BA (Energy Storage, Battery)
    CP (Energy Storage, Concentrated Solar Power)
    FW (Energy Storage, Flywheel)
    ES (Energy Storage, Other)
    HA (Hydrokinetic, Axial Flow Turbine)
    HB (Hydrokinetic, Wave Buoy)
    HK (Hydrokinetic, Other)
    BT (Turbines Used in a Bnary Cycle, including those used for geothermal applications)
    WS (Wind Turbine, Offshore)
  • Help: When using the Window --> Auxiliary File Format option to open the auxiliary file format PDF document and the document cannot be found on the local computer, this file will instead be opened from the PowerWorld website.
  • Oneline Diagrams: Modified contour dialog so that the enabling/disabling of the items to contour can consider Geographic Data Views.
  • Transient Stability: Added the line relay model SCGAP.
  • Bug Fixes

    • Case Information Displays: Fixed an access violation that could occur when viewing the Case Info Customizations table.
    • File Formats: Fixed bug in writing out the Qtable section to a Version 19 EPC file if a generator had exactly 10, 20, etc. (multiple of 10) points on the qtable. In this situation we would write out a slash (/) character at the end of the record inappropriately.
    • File Formats: Subdata classes contained in Aux Export Format descriptions cannot be read or written to PWB files due to a file format error. This cannot be fixed until Simulator version 20. Until a fix is available, subdata classes will be deleted if found when loading PWB files and will not be written when writing PWB files. Appropriate messages will be sent to the message log.
    • Integrated Topology Processing (ITP): Bus shunts were not being restored correctly from a system state stored while the case was consolidated to a system that is not consolidated. There would probably have also been problems with a state stored not consolidated and restored consolidated. Restoring the bus shunts has been fixed no matter what consolidation status you are in while storing or restoring.
    • Sensitivity Calculations: In the general LCDF calculation, the result will be returned as 0 if an open line is between two islands.
    • Transient Stability: Fixed bug in which substation fields saved to a TSR file were being recognized when checking if any substations were saved to RAM.

December 30, 2015

Features and Improvements

  • File Formats: Added ability to write the *.M files used for input to the MatPower matlab function.
  • Bug Fixes

    • General: Changed name of DFACTS field from "Injected Number of Modules per Ph" to "Number of Active Modules per Ph". This more closely follows the naming convention we use elsewhere.
    • Transient Stability: Fixed bug in which invalid islands were not initially disabled.
    • Transient Stability: Modified some strange blinking behavior that could occur when configuring transient stability dialog to update frequently during the simulation run.

December 23, 2015

Bug Fixes

  • General: Changed the behavior of the DFACTS current threshold fields so that they depend upon the line's current limit.
  • Transient Stability: Fixed bugs with the parameter check of certain parameters than needed to be greater than zero but the auto-correction was setting the parameters to zero again. Now they will be set to Mult*TimeStep.
  • User Interface Dialogs: When using the Scale dialog to scale by Injection Group, the New Value and Scale Factor could unexpectedly go to zero. This has been fixed.

December 21, 2015

Bug Fixes

  • Available Transfer Capability (ATC) Tool: Fixed bug with the WriteToExcel button on the ATC dialog.
  • Distributed Computation: Fixed issue with only half of the processes getting allocated and the other half failing during distributed runs.
  • Transient Stability: Fixed issue with reporting Va field in ESAC7B exciter model. This was just a reporting issue - the value was being used correctly.
  • Transient Stability: Fixed problem with Distributed Computing and Transient Stability so that runs can be done without making TSR files.

December 18, 2015

Features and Improvements

  • Contingency Analysis Tool: When displaying LODF/LCDF calculations as part of the Contingency Sensitivities tool, if a branch causes the island topology to change, 'Island Change' will be reported instead of the LODF/LCDF and all other values will be blank. The Contingency Sensitivities Tool is available under the right-click menu of a particular contingency violation.
  • Contingency Analysis Tool: Added ability for the variables of an Expression to have a flag indicating that the value should be evaluated in the contingency reference state. This then allows you to create an Expression which is a function of both pre and post contingency variables.
  • Contingency Analysis Tool: Added ability for the variables of a ModelExpression to have a flag indicating that the value should be evaluated in the contingency reference state. This then allows you to create a ModelExpression which is a function of both pre and post contingency variables.
  • Contingency Analysis Tool: Add ability for the variable being evaluated in a ModelConditionCondition to specify that it be evaluated in the contingency reference state. As an example that would use this, a single ModelCondition can be created that checks two ModelConditionCondition on a Branch Object as follows.
    1. Status = Closed IN REFERENCE
    2. Status = Open
    This makes it easier to create logic to evaluate a change from the reference state.
  • Oneline Diagrams: Added ability for showing dialogs for Generators, Loads, and Branches when right-clicking on the various background lines shown on Areva DDL oneline diagrams inside Simulator.
  • PV and QV Curve (PVQV) Tool: Added popup hints for all the various options on the PV Curve dialog (simular to what has already been done for the Contingency analysis and Transient Stability dialogs a few years ago)
  • Simulator Automation Server (SimAuto): Modified so that when running a SimAuto instance we never write the list of Recently opened files to the registry. This should only be modified when opening files in the user interface
  • Transient Stability: When loading in TSPlotVertAxisGroup objects from a Version 18 and earlier PWB file, if the axis group contained ALL generator speed plot series AND the user had user-specified Min/Max values on the vertical axis scale, then these values were based around nominal frequency. In Version 19 however, we now store generator speed in per unit instead of scaled by nominal frequency. To fix potential troubles with vertical axis groups on plots, we will now automatically scale the user-specified min/max value in this situation.
  • Transient Stability: Modified DEGOV1 to not enforce any contraint on the size of the T3 and T4 time constaints. Also modified so that validation enforces that TD must be no larger than 12*TimeStep
  • Transient Stability: Fixed error in loading the SVCBAS USRMDL from a PTI DYR file. It wasn't reading the regulated bu terminal correctly.
  • Bug Fixes

    • Distributed Computation: When running distributed computing tools it is possible for multiple instances of Simulator to close simultaneously and then try to write to the windows registry all at the same time. This was causing a conflict resulting in dialogs appearing indicating you can't write to the registry. This has been fixed by not writing to the windows registry from a SimAuto instance that was launched by PowerWorld's distributed computing tools.
    • Distributed Computation: When running distributed Transient Stability, Simulator was going through and validating the transient stability models for every contingency. This is unnecessary, and it is only necessary to validate against the largest time step, so now validation is only done once on the largest time step.
    • Distributed Computation: When running distributed Transient Stability, Simulator was continuing to write TSR files even when the user had chosen not to store to hard drive or to RAM (you might do this if you were only looking at the transient limit monitors.) This has been modified for now so that a TSR file is still written but it is configured so it doesn't store anything (it will be about 4 KB). We will likely remove this shortly as well.
    • Power Flow Solution: Fixed an issue with min and max of svcs that provide continuous Mvar control. In some situation they would become stuck at their min or max limit and not back off the limit when appropriate.
    • Simulator Automation Server (SimAuto): Added additionally checking to ensure that only one instance of SimAuto can write to the registry at a time.
    • Transient Stability: When writing an AUX file containing the Min/Max results for generators, some switched shunts that model SVCs were being included in this AUX file. These have been removed.

December 15, 2015

Features and Improvements

  • File Formats: Added ability to read the *.M files created for input to the MatPower matlab simulation.
  • PV and QV Curve (PVQV) Tool: Added new option with PV tool to Restore Initial State on Completion of Run. The default is NO because this is what we had been doing.
  • Transient Stability: Added ability on the transient stability dialog to show only state limit violations that are "modified" or those which are "not modified". There are now three tabs to show either All, Modified, or Not Modified.
  • Bug Fixes

    • Contingency Analysis: When choosing to show contingency element definitions in the user interface "by label", Simulator was still showing the definitions by number. This has been fixed so that the GUI shows them by label when chosen.
    • Transient Stability: Fixed error with the Distribution Equivalent. In Nov 25 patch we added support for transformer switching in the distribution equivalent load model. In this addition however we were not obeying the LTC flag of zero which indicated that tap switching was not available for the transformer and were instead switching all transformers. This has been fixed to switch those transformers for which this control is enabled.
    • Transient Stability: Do not include initialization limit checking for LD1PAC stall voltage when the bus is out of service.
    • Transient Stability: Added additional validation checking on the EXWTGE model for values of XIQmax and XIQmin to catch values of 0.0 which indicate they should be set to default values of 1.45 and 0.5.
    • User Interface Dialogs: Fixing errors with defining a DFacts device which can be capacitive.

December 11, 2015

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Adding Trim(), LTrim() and RTrim() to the expression parser.
  • Case Information Displays: Adding Trim(), LTrim() and RTrim() to the expression parser.
  • General: Added MW Transactions to Model Expressions, Model Conditions, Model Fields, and Custom Monitors.
  • PV and QV Curve (PVQV) Tool: When opening the QV Curves dialog, the columns being shown in the Bus tab are processed. If the column "Selected" is in the list and the column "QVSelected" is NOT in the list, then the Selected Column is replaced with "QVSelected". In Version 18, we changed QV curves so that only buses that are flagged as QVSelected=YES are processed. In Version 17 and earlier we used the field Selected=YES. As a result, older PWB files may exist which have the Selected column in this table causing confusion. This change will avoid this confusion.
  • Transient Stability: Added ability to load several USRMDL records using in Alaska from a DYR file.
    USRMDL SVCBAS is converted to a SVSMO1_AK_A
    USRMDL GTAKGE is converted to a GAST2A_AIR
    USRMDL GTAKWD is converted to a GASTWD_AIR
    USRMDL CSVCAB is converted to a SVSMO1_AK_B
    USRMDL HRSG is converted to a HRSGSimple
    GVABESis converted to a CBATTERY
    ALSTM1 is converted to a SVCALS
    GEWGC1/GEWTE2/GEWTT1/GEWTP1/GEWGC1/GEWTA1/GEWPLT are converted to WT3G2/WT3E1/WT3T1/WT3P1
  • QV Curves: Added User Defined Integer field with QV results. This might be useful for selecting groups of results to plot together.
  • Retriever: Updated alarm inhibit feature to support inhibiting of only changed aliases in addition to the ability to inhibit all aliases associated with an alarm.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug when loading interface elements from an AUX file when the keywords for "BRANCH" etc.. used lowercase characters. In some locations it was not properly reading the interface elements.
    • Auxiliary Files (SCRIPT and DATA Sections): Store Line Tap by default with Transformer data. This had only been stored with Branch data and might be needed if the fixed taps are anything other than 1. Reordered the priority fields for the transformer nominal kV, fixed taps, and actual tap so that we end up with the correct tap after loading an aux file.
    • File Formats: Fixed bug when appending PWB cases and the same substation exists in both cases.
    • PV and QV Curve (PVQV) Tool: Fixed bug with ramping PV transfer in which the source contains the system slack. The slack would not actually move and could reach a situation in which no ramping is actually being done even though the tool looks like it keeps increasing the transfer.
    • PV and QV Curve (PVQV) Tool: Fixed invalid pointer error associated with monitoring inadequate voltages with a PV run.
    • Transient Stability: Fixed access violation on Stability tab of the transformer/branch dialog.
    • Transient Stability: Modified the initialization of the svcals, svsmo1_ak_a, and svsmo1_ak_b switched shunt models for SVCs.
    • Transient Stability: Modified the initialization of the Hydro_Bradley governor model so it works with stabilizers that use the mechanical power as an input.
    • User Interface Dialogs: Fixed bug when opening the Model Condition dialog if the class of the filter was different than the class of the object. This worked correctly on the dialog while defining the Model Condition, but when choosing show dialog on an existing model condition it was not properly populating the dialog.
    • User Interface Dialogs: Added support for reading/writing switched shunt stability models from the DYR format.
    • User Interface Dialogs: Fixed bug with how much you can scale each parameter. Bug would force the limit to 99999.

December 7, 2015

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that was creating a duplicate of the same controllable fixed shunts in an svc shunt when loading an AUX file defining them.
  • Transient Stability: Added initial limit violation checking on the CSVGN5, CSVGN6, BPASVC, SVCWSC, and VWSCC models if the BSVS is outside the Bmax and Bmin input parameters. Also modified checking to ensure the Bpmax >= Bmax and Bpmin <= Bmin for these models.
  • Transient Stability: Modified so that when the CDC4T, CDC6T, CDC6, EPCDC dc tranmission line models have a minimum current specified and that minimum current is higher than the initial operating current of the DC line, then the transient stability DC line model will ignore the minimum current and treat it as the initial operating current instead.
  • Transient Stability: Fixed initialization of the WT3P1 model when ThetaMin was negative.
  • Transient Stability: Modified the WT3P1 model so that the absolute value of PiRat is used. Previously negative values of PiRat caused the model to be unstable.
  • Transient Stability: Modified validation checking on the PlayInRef model to ensure that the signal index values Pref_Index and Vref_Index are not beyond the number of signals available in the referenced playin model.
  • Transient Stability: When saving transient stability model to an AUX file, the LTC1 models were not being stored. This has been fixed.
  • Transient Stability: Modified storage of the Rotor Angle for generator models. This field was storing a value even for non-synchronous machines which was confusing. The Rotor Angle in results will now always be stored as 0.0 for any generator which is not either a synchronous machine, PLAYINGEN, InfiniteBusSignalGen, WT3G1, or WT3G2. (The wind turbines have a PLL state that is a useful field to track similar to a rotor angle).
  • User Interface Dialogs: Modified pop-up menu in log to show a checkbox beside "Show Time Stamp" rather than changing caption from "Disable Time Stamp" to "Enable Time Stamp". Also fixed a bug where that change wasn't happening at all.

December 1, 2015

Bug Fixes

  • File Formats: Changed the caption of the dialog that appears when loading an *.mon file from the limit group case information display. It now says
    "Would you like to reset all Bus, Branch, and Interface Monitor Fields to YES?" which accurately reflects what it means. Also, it will now always load the *.mon file even if you click NO in response to this dialog. Previously it would not load the MON file if you chose No.
  • Transient Stability: Fixed bug in the feature to Clone Contingency on the transient stability dialog.
  • Transient Stability: When using the script command TSSolveAll(Yes) to run a Distributed Transient Stability simulation of many multiple contingencies, the transient stability results were not being properly returned. This has been fixed.

November 30, 2015

Features and Improvements

  • Case Information Displays: Modified the way left-clicking on column headings works for both sorting and reordering columns. Previously to reorder columns by dragging column headings you were required to hold down the Ctrl key before clicking with the left mouse button. Previously for sorting, columns were sorted immediately on the left mouse-DOWN. This worked just fine, but many users were not aware of the need to hold down the Ctrl key to reorder columns so this feature was largely unknown. It has now been changed as follows.

    1. Left-click and dragging the mouse button will always reorder columns regardless of whether the Ctrl, Shift, or Alt keys
    2. Sorting will now occur on the Mouse-UP instead of immediately upon Mouse-DOWN.
    (This is done so that Simulator can first figure out if column headings are being dragged or not)
    2a. If you did NOT drag and move any columns, then on Mouse-UP we will perform the sorting of the column
    2b. If you did drag and move some columns, then on Mouse-UP and will complete the reorder of columns
  • Bug Fixes

    • Contingency Analysis: Fixed Typo in column header for Switched Shunt object field "CTG Volt Low". It said "CTG Low High" previously.
    • File Formats: Modified reading of the MON file to properly handle reading MONITOR BRANCH lines which have a comment at the end of the line of text. Previously this was causing the lines to not be read in.
    • File Formats: fixed error with writing out multi-terminal DC Converter records to the EPC version 19 format. It was writing an extra double quotation mark which was causing an error in the file format.
    • Transient Stability: added support to the Distribution Equivalent for using the Rcomp and Xcomp line drop compensation values. Previously these were ignored.

November 24, 2015

Features and Improvements

  • PV and QV Curve (PVQV) Tool: @CASENAME, @CTGNAME, and @CTGMEMO will now work as special keywords in the title block for PV plots in a similar manner to the Transient Stability Plots.
  • Transient Stability: Adding a new global transient stability option for "Minimum Voltage For Frequency Relay". When the per unit voltage is below this threshold then all frequency relays will treat their measured frequency as nominal frequency. This was done to mimic the voltage inhibit flag of real relay models and also to prevent motors stuck behind a fault from tripping on low frequency when the measured frequency behind the fault is suspect.
  • User Interface Dialogs: On various dialogs that have a custom tab (Bus, Gen, Shunt, Branch, etc...) which shows the custom fields, the assignment of the DataMaintainer may now be done on the Custom tab
  • User Interface Dialogs: Modified the Switched Shunt dialogs to be sizable to make editing their transient stability models easier.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug that would not allow using the special busloc ALL to return all available fields with a particular variablename.
    • File Formats: When writing out shunt data to an EPC file, we had been writing -1 for the bus number of the controlling shunt when there was no controlling shunt. Now we are writing 0.
    • File Formats: Added svc important fields needed when saving case as an entire case to an aux file.
    • Transient Stability: Adding in support for transformer tap switching in the distribution equivalent model and in the CMPLDW model. Previously this was being ignored.
    • Transient Stability: When showing plots, the legend text was always appearing as black instead of the same color as the plot series to which it refers. The font color will now again be based on the plot series to which it refers.
    • Transient Stability: For load object fields shown in the plot designer field list, the "Relay" and "Feeder" Other fields were flipped in the user interface. The folders for the feeder fields would say "relay" and vice versa. This was a cosmetic error and is fixed.

November 19, 2015

Features and Improvements

  • General: New IsTrue function added with expressions. Will return 1 if the string entered is: T, TRUE, CONNECTED, CLOSED, YES, Y, or 1. Otherwise return 0.
  • Bug Fixes

    • Contingency Analysis: Fixed a bug that would not properly return the value of the Amount to use in a contingency action if the amount is determined by a Field of the object. These actions would always be skipped even if their model critieria was met because the Amount was considered invalid.
    • General: Fixed behavior where if a model expression evaluation results in an error (due to bad conversion, syntax error, etc.) that it doesn't throw an exception but instead shows the error in a new Error field. If an unknow exception occurs, then it throws the exception.
    • General: Fixed a bug directly accessing PartPoint objecttypes of type BUS through actions like SetData.
    • OPF Reserves Tool: Fixed access violations that could occur while solving the primal LP when using OPF Reserves.
    • Transient Stability: Updates to Measurement Object for storing to auxiliary file.