What's in the Simulator 13 Patch?

Select one of the following links to view descriptions of the changes incorporated via the PowerWorld Simulator Patch files

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October 5, 2007

New Features

• User Interface: Added the File Menu to the Onelines Ribbon Tab so that buttons on that menu can be added to the Quick Access Toolbar.
• Case Information Displays: Added new Fields Pane to the Model and Display Explorer giving direct access to the columns available for each case information display. You may left-click and drag fields onto the case information display to add fields.
• Case Information Displays: Modified Case Information Displays so that holding down the CTRL key and then dragging a column heading allows you to move column order. You may also drag the field over to the new Fields Pane to remove it from the case information display.
• Case Information Displays: Fixed a potential problem access violations that could occur when opening Display Explorer.
• Auxiliary File Formats: On the Auxiliary File Export Format Description dialog, a button has been added to Create Format for Complete Case. This automatically creates a format description that is similar to that used by Simulator when choosing to Save Case, As Auxiliary File.
• Oneline Diagrams: When manually drawing generator, load, and switched shunt objects on a substation-based diagram, Simulator now properly determines which substation is closest to where you click.
• Oneline Diagrams: The refreshing of anchors of generator, load, and switched shunt objects on a substation-based diagram has been modified to properly anchor to the substation.
• Oneline Diagrams: Increased the speed of refreshing anchors when done by toggling the Anchored checkbox on the Format Dialog.
• Available Transfer Capability: Added new field to transfer limiter results that shows the unaltered MVA limit that is defined with a monitored element.
• Available Transfer Capability: When running iterated ATC methods, ramping transfer, or moving to one of the multiple scenarios, the minimum voltages for reducing load are set to 0.

Bug Fixes

• Auxiliary Files: Access to the multi-directional PTDF value results through the script commands such as SaveData was not working properly and blank values were returned. This has been fixed so it works in scripting.
• User Interface: When using multiple monitors and dragging the message log outside of the main Simulator Window, on some systems it was possible to cause other windows to a portion of the screen that isn't visible.
• Oneline Diagrams: The 3D Stacks for generator objects were not being drawing with the proper width. This has been fixed.
• Power Flow Solution: Added checks throughout to prevent the two-terminal and multi-terminal DC line converters from having their tap ratios set to zero. This should not be allowed and is no longer allowed.
• Power Flow Solution: In Simulator 13, the ability of the area interchange control to handle areas that span multiple islands has been greatly improved. A bug was introduced for Super Areas that span multiple islands which has now been fixed.
• File Formats: Fixed a bug in writing out the fixed tap ratio on the secondary and/or tertiary windings of a three-winding transformer if the transformer nominal voltage base was different than the bus nominal voltage.

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October 11, 2007

New Features

• None.

Bug Fixes

• File Formats: Fixed bug that would make it impossible to save a PWB file after applying an advanced sort to the Area Reporting or Zone Reporting case information displays on the Limit Monitoring Settings Dialog.
• Auxiliary Files: Fixed bug introduced in October 5 patch with loading in branches and interfaces with custom fields greater than the number of currently defined custom fields.
• Auxiliary Files: Fixed bugs related to accesses AreaTieLine or ZoneTieLine object through the script commands.

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October 22, 2007

New Features

• File Format: Modified the default behavior when reading a PTI RAW file. Simulator now estimate from the input data how the treatment of loads that belong to a different area than their terminal bus should be done in the area interchange equations.
• Case Information Displays: Added new case information displays to the Model Explorer to show Fault Analysis related information.
• Case Information Displays: Modified the right-click menu "Insert" option on the Case Information Display so that it is still enabled when you right-click below the presently defined records.
• Oneline Diagrams: Added several pre-defined border Sets on the Auto-Insert Borders dialog.
• Auxiliary File: Fixed a potential bug that could occur when reading in an AUX file that created a two-terminal DC transmission line. The problem was that the transformer tap ratio was being read as zero causing a divide-by-zero error.
• Auxiliary File: Modification throughout so that the Fault Analysis data can be read from an Auxiliary File format while in Edit Mode.
• SimAuto: When using the command RunScriptCommand() in Simauto, Simulator previously would generate a temporary text file used in some internal routines. This empty text file would then be deleted after running the command. For some users, under some situations this file was being created by not deleted. Simulator has been changed so that this file is not longer needed.

Bug Fixes

• Oneline Diagrams: Modified interaction with the Geo Data Views when creating a new oneline diagram on which to draw the Geo Data View.
• Oneline Diagrams: Fixed potential access violation when using a lookup table the Dynamic Formatting feature.
• Oneline Diagrams: Fixed bug in which dc lines were not displaying correct MW flow when option MW & Mvar option was chosen.
• Oneline Diagrams: Fixed access violation when right-clicking on an unlinked transmission line display object.
• User Interface Dialogs: Fixed nuisance access violation when deleting a Data Block Description on the Auxiliary File Export Format Description dialog.
• User Interface Dialogs: Changed default shunt impedances to zero for the zero-sequence data for a transmission line.
• User Interface Dialogs: Fixed potential error on the Nomogram Dialog.
• User Interface Dialogs: Fixed error with the Add New button on the Limit Group Dialog
• Case Information Displays: Fixed potential error that could cause under unusually situations that could cause program halt when showing header hints or hints for shown fields on the case information display.

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November 13, 2007

New Features

• Case Information Displays: Modified the drop-down list of Advanced Filters so that the active filter is indicated with a check-mark.
• Case Information Displays: Started work on enhancing the plot columns feature. It now allows specification of color, line type, etc... for each column.
• Case Information Displays: Modified the user interface throughout so that the "Use Area/Zone Filters" check-box is only available for objects to which these apply.
• Case Information Displays: On the Area Case Information Display, added the "Area Slack Bus" as a default column
• Case Information Displays: Increased the time that a hint is visible when hovering over a case information column from 2.5 seconds to 10.0 seconds.
• Case Information Displays: Modified so that when opening a new Model Explorer the Explore Pane is always opened by default.
• User Interface Dialogs: On the Interface Dialog, add the weighting column by default to the Interface Element Grid.
• User Interface Dialogs: When inserting a bus graphically on a oneline diagram, modifications were made to provide better feedback on the the Bus dialog as to whether or not a new bus is being added to the power system model.
• User Interface Dialogs: Added ability to Tile Horizontally or Tile Vertically. This is available from the Windows Ribbon Tab.
• User Interface Dialogs: Added Difference Flows Menu to the Case Data Ribbon Group on the Case Information Ribbon Tab.
• Bus View: Brought back a feature that allows the graphical insertion of new generators, loads, or switched shunts on a Bus View. This was removed in an earlier patch due to a bug that has now been fixed.
• Contingency Analysis: Changed the default for future cases so that the Contingency Analysis Make Up Power uses the option "Generator Participation Factors From Entire Case Directly"
• Contingency Analysis: Added a new column for Aggregate MW Overload caused by a particular contingency.
• Optimal Power Flow: Cleaned up the graying out of Area fields related to the OPF options to make them consistent and provide better feedback as to why they are disabled.
• OPF Reserves: Added support for doing Difference Flows comparisons of the OPF Reserve results
• Fault Analysis: Added the Case Information Toolbar to the Fault Analysis Dialog.

Bug Fixes

• File Formats: Fixed bug writing out reactive capability curves in the Q table data section to the EPC file format.
• File Formats: If any transient stability models were defined for a generator, the ability to Append to the case was not working properly. This has been fixed.
• Case Information Displays: When reading in an Advanced Filter from a version 12.0 or earlier PWB file, if the filter conditions applied to an integer field type (such as bus number), then the filter conditions was not being read properly. This has been fixed. The bug was related to a new feature in Simulator 13 in which we now store integer values as integers instead of floating point numbers. (fixed bug in older versions where 123456789 was treated as 123456790).
• Case Information Displays: Fixed bug that would occur when Ctrl-Click was used on the Model Explorer to open a new Model Explorer.
• Case Information Displays: On the Model Explorer, the options to "Save Selected Records or "Save Selected Records and Columns" was not working properly and was saving the entire case information display. This has been fixed.
• Case Information Displays: Dynamic Formatting can be set to apply to case information displays. When using a lookup table associated with the Fill Color or Font Color however, this was not working properly. This has been fixed.
• Case Information Displays: Fixed error that would occur when trying to paste data into PartPoint list on the Injection Group case information display. This error occurred because the "Contained By" column was not shown even though it's a key field.
• Oneline Diagrams: When using the Bus or Substation palette, by default lines, generators, loads, and shunts are auto-inserted as buses/substations are added to the oneline. There was a bug that fields were not being properly inserted automatically until AFTER the Auto Insert Options was opened. This has been fixed.
• Oneline Diagrams: Fixed bug in copying and pasting records and objects from one case to another. The loads, gens, lines and some fields were not being properly pasted.
• Oneline Diagrams: The Recalculate Contour button of the Contouring Menu on the Onelines Ribbon Tab was not working properly. This has been fixed.
• Contingency Analysis: Removed the "Set Options" and "Reset" button on the Options Tab of the Contingency Analysis Dialog. These buttons did not actually perform any function any more.
• Contingency Analysis: Modified so that when opening the Contingency Analysis form the list of contingencies is activated immediately so that the Case Information Toolbar acts on this case info by default.
• PV and QV Curve Tool: The Injection Group columns for tracking data in the PV and QV Curve tool were not appearing as toggleable (green). This has been fixed.
• PV and QV Curve Tool: Fixed bug that would not report the correct transfer level limitation when using the option to stop when voltages become inadequate.

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November 15, 2007

New Features

• Case Information Displays: Added ability to copy/paste the fault analysis input parameters. Also gives ability to read/write from an Auxiliary File.
• SimAuto: Previously, when starting a SimAuto process, an existing Simulator instance would be taken over by the SimAuto process. This has been changed so that existing Simulator instances are left open and a new Simulator process is started by SimAuto.

Bug Fixes

• User Interface Dialog: Changed the injection group field for "Load MW Particiaption Factor" to consider all loads in the injection group. Previously it was only considering loads marked as AGCable which made the value inconsistent with the value shown on the injection group dialog.
• SimAuto: The Message Log was becoming visible up when running a SimAuto process. This has been fixed so that the message log does not appear.
• Oneline Diagrams: Simulator does not support copying and pasting data records from one case to another by graphically selecting DC lines, Interfaces, or MS lines. Fixed a bug to avoid access violations when trying to do that.
• SCOPF: Fixed a potential bug that occurs when setting the SCOPF Basecase Solution Method to the Optimal Power Flow. If you were also using fast start generators this could cause errors in the SCOPF solution causing it to terminate at an invalid solution.

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November 21, 2007

New Features

• Case Information Displays: Fixed bug that was preventing the Area Slack Max MW field from being available.
• Case Information Displays: Fixed bug with updating the Fields Pane when toggling between two case info displays that showed the SAME object types.
• Contingency Analysis: Previously the auto-insertion of contingencies routine did not allow the auto-insertion of Generator or Bus outages at the slack bus. Simulator actually handles this outage fine, so the restriction of the auto-insertion has been removed.
• SCOPF: On the Price Details case information display, modified so that the column headings regarding contingency violations include the name of the contingency also.

Bug Fixes

• File Format: A bug was introduced in Simulator 13 when writing out PWD oneline files out to version 12 or earlier PWD versions. This bug has been fixed in Version 13, and a fix has also been added to Simulator 12.0 to allow it to gracefully read the PWD files even if they were written incorrectly.
• Bus View: Fixed problem with circuit breaker sizing on the BusView. Previously they were too large
• User Interface Dialogs: On the Move Equipment dialog, the case information display showing the devices to move was not being refreshed properly when opening the dialog. This has been fixed.

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December 5, 2007

New Features

• Oneline Diagrams: Adding support for showing Geo-Data View oneline objects in 3D.
• Time Step Simulation: Added support for showing the Case Information Toolbar on the Time Step Simulation dialog.
• Case Information Displays: Added the ability to copy and paste sequence impedance data for branches.
• Case Information Displays: Modified the list of fields for Limit Violations to group them in a logical manner aiding in the better understanding of what the fields mean.
• Contingency Analysis: The list of contingencies inside Simulator previously was not sorted alphabetically by name. For contingencies lists shorter than about 5,000 this was fine, however some users are starting to define contingency lists in excess of 500,000 contingencies. This was causing huge performance problems in interacting with the model. The contingency list now maintains a sorted internal list so that lookups of contingencies by name are much faster allowing for much larger contingencies lists to be defined.
• Contingency Analysis: Changed the user-interaction with the Contingency Definition Dialog to not use a drop-down box anymore. Drop-downs to not work for very long lists of objects.
• Auxiliary Files: When saving out the limit monitorings settings, previously no information regarding specific voltage limits for specific buses was stored. This is now automatically added to the Limit Monitoring Auxiliary file when saved (this includes on the Limit Monitoring dialog as well as from the Contingency analysis, ATC, PV, QV, etc... AUX files.

Bug Fixes

• General: The Lock and Key mechanism in Simulator relies on the Windows Management Instrumentation (WMI) part of the windows operating system. On rare occasions users were experiencing errors in their WMI installation and as a result the software could not be executed. Fixes have been made to allow the lock/key mechanism to work under these situations, though PowerWorld still recommends fixing the windows installation to ensure the WMI will work properly.
• Bus View: Fixed problems with onelines opening as maximized yet not spreading themselves across the entire window.
• Bus View: Fixed bug that occurred when a bus view was reduced to height zero. This caused divide by zero errors.
• Contingency Analysis: When using filters to auto-insert BUS and GEN outage contingencies, the filters were not being properly applied. This has been fixed.
• Security Constrained OPF: Added the storage of several SCOPF solution options in the PWB format which previously were not in the PWB file. This included the SCOPF Base Case Solution Method.

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December 7, 2007

New Features

• Contingency Analysis: Added the ability to define special inclusion and exclusion monitoring lists of elements with each contingency. This allows you to NOT monitor specific elements, or to monitor only a specific list of elements. For Version 13, this feature is now available, but you will not be able to store these specifications with the PWB format until version 14.

Bug Fixes

• Oneline Diagrams: Fixed an error that was caused when opening a oneline diagram using "Name_kV linking". The error causing diagrams to not link when opening this way and caused access violations.
• User Interface Dialogs: When showing the list of advanced filters and then right-clicking and choosing Show Dialog, and error would occur if a filter was then deleted from the Advanced Filter Dialog.

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December 12, 2007

New Features

• Power Flow Solution: Made some minor changes to help speed up the power flow solution.
• Contingency Analysis: Optimized the calculations done for Linearized Contingency Analysis to speed them up substantially. Linearized contingency analysis should now run approximately 3 times faster.
• Contingency Analysis: When using make-up power in the contingency analysis tool, the generation make-up loop was using a very low tolerance (4 times the mismatch solution tolerance). This was causing solution times to be much slower than desirable. We have changed this tolerance to be 5 MW instead now which for typical single-line outages results in a contingency solution speed between 2 and 3 times faster.
• Auxiliary Files: Added a new script command CloseOneline("filename")
• Auxiliary Files: Added a new script command when running SimAuto called LoadAXD("AXDfilename", "onelinefilename", CreateIfNotFound).

Bug Fixes

• File Formats: Fixed potential bug when reading in a PWB file that contained multi-section lines.
• Auxiliary Files and Power Flow Solution: Fixed a solution bug introduced in the December 5 patch that would occur if you read a power system case from an Auxiliary File.
• Oneline Diagrams: Fixed a bug that was causing the generator, load, and switched shunt oneline objects to not draw their circuit breakers

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December 19, 2007

New Features

• Contingency Analysis: Added new option for the Make Up Power AGC Tolerance on the Contingency Analysis dialog.
• Contingency Analysis: Added ability to filter the contingency analysis records by Branch, Generator, Load, Switched Shunt, Interface, Injection Group or DC LIne. A Contingency record will meet the filter if it contains any of these objects in its element actions that meet their filter.

Bug Fixes

• File Formats: Modified the writing of GE EPC files so that the Generator MVar output is written to 2 decimal places instead of 1.
• Case Information Displays: When using the DC approximation and then showing the Area Losses and Interchange in a case information display, the value for losses was being calculated incorrectly (it should just be zero). The loss error resulted in the interchange being shown incorrect as well. Note that the actually solution algorithms were using the correct values internally, so this was only a user interface error.
• Auxiliary Files: Fixed the OpenOneline() script command so that in 3D when going to a view and toggling full screen, Simulator properly does the Toggle Full Screen FIRST and then the go to view.
• Oneline Diagrams: Fixed the Short-Cut key method so that when choosing to both go to a view and Toggle Full Screen, Simulator properly does the Toggle Full Screen FIRST and then the go to view.
• Oneline Diagrams: Fixed issues with Font Width and Height being properly sized in 3D onelines.
• Oneline Diagrams: Modifed 3D onelines so that layers that are now being shown to not show their elements when in 3D.
• User Interface Dialogs: More modifications to ensure that maximized windows to not appear as unmaximized even when they are maximized.
• User Interface Dialogs: When inserting a generator in Edit Mode, an access violation was recently introduced. This has been fixed. The error was a nuisance and related to moving the stability models onto the dialog.
• Power Flow Solution: Fixed solution error in the Decoupled Power Flow that could occur for remotely regulated buses. Would result in power flow divergence.
• PV Curve Tool: Fixed a bug in the PV curve tool that could occur when ramping if the source or sink contained the island slack bus.

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January 4, 2008

New Features

• File Formats: Modified the reading of RAW files so that any comments found at the end of a line in the RAW file will be read into the corresponding record as the Memo Field. Memo are NOT written back out to the RAW file however.
• Auxiliary Files: Modified the CloseOneline() command so that if the name is empty, then Simulator closes the last focused oneline diagram.

Bug Fixes

• File Formats: Fixed an error when loading in Advanced Filter Conditions that contained more than one value (such as the between comparisons).
• Oneline Diagrams: When in Run Mode, if any field which had a background fill color its text was presently blank would appear as a small square with the fill color. This has been changed so that if the text is blank, then nothing is drawn to the screen.
• Oneline Diagrams: Fixed bug in text object. When no text, it won't be displayed in run mode.
• Oneline Diagrams: The Oneline object Format Dialog was not working to change fields to show values represented by the Custom Field Descriptions.
• User Interface Dialogs: When opening the Area Dialog, the area slack bus number was not being set properly and this was causing the Area Slack bus to be removed from the Area. This has been fixed.
• Auxiliary Files: When reading in interface elements using Name_NomkV values as secondary keys, the direction of the monitoring was not always being set correctly. This has been fixed.
• Auxiliary Files: Made sure that when using the command CloseOneline that the a prompt to save the oneline is not generated.
• Contingency Analysis: Fixed a bug introduced during optimizations made on December 12. This would result in erroneous results if you chose "Solve Selected Contingency" and then immediately choose "Solve Selected Contingency" on the SAME contingency again.

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January 12, 2008

New Features

• PV and QV Curves: Modified QV Curve Options page so that the user can now set a check box to save or not save results to comma delimited text files. If the box is checked, but a file name is not specified, Simulator treats this the same as if the box is unchecked.

Bug Fixes

• User Interface Dialogs: Fixed an error that occur whenever you tried to delete a Custom Field Description object.
• User Interface Dialogs: When changing the color scheme of the Ribbon Settings, this choice is supposed to be saved in the Windows Registry so that the next time you open Simulator your color scheme is maintained. This as not occurring and this patch fixed this problem.
• Contingency Analysis: Fixed error when writing out the old contingency text report and including the database friendly files. Problems could occur for Contingency elements involving gens, loads, and shunts that used the Move, Set, and Change By actions.
• PV and QV Curves: Fixed access violation that would result when writing out the QV tracking results to file and there were no newly crictical scenarios. The error produced in the QV curve didn't make it clear this was the error, but it is now fixed.

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January 28, 2008

New Features

• Case Information Displays: Added many new fields that show a count of the number of generators, loads, branches, etc... that are contained by Areas, Zones, or Substations.
• Oneline Diagrams: Modified the oneline links so that they can also open Display Auxiliary Files (AXD).
• Fault Analysis: Simulator defaults all zero-sequence parameters for transmission line to be equal to 2.5 times the positive sequence impedances. Simulator continued this behavior when reading in PTI Sequence files, but it appears that PTI assumes that lines are open in the zero-sequence model if no zero-seqpence data is specified in the *.seq data file. When reading *.seq Simulator now gives the user the ability to assume this behavior.

Bug Fixes

• File Formats: When reading in PWB files with custom fields defined, Simulator was not always properly updating the Custom Field Descriptions to include the number of values specified. This has been fixed.
• Power Flow Solution: Fixed bug that would occur when equivalencing a bus that had NO generation, NO load, and NO shunt connected, and was also connect to the system by a single branch with had a non-zero phase shift.
• Oneline Diagrams: Fixed the Display Auxiliary Files (AXD) so that they can be opened in Run Mode.
• User Interface Dialogs: Fixed a problem with the case information displays not properly refreshing when you first open the DC Loss Load Multiplier dialog.
• Available Transfer Capability: Fixed an error that could occur under specific situations when using the ATC Solution method "(IL) then Full CTG Solution". If the Full Contingency solution repeatedly failed the result wasn't being reflected correctly.

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February 6, 2008

New Features

• None.

Bug Fixes

• File Formats: The EPC and RAW file formats have no indication for a generator of "AVR = NO". To replicate this behavior, PowerWorld now writes out the Min/Max VAR of such a generator to be equal to the present Mvr output of the generator.
• File Formats: The RAW format does not support three-winding transformers without a tertiary winding. Fixed error so that three-winding transformers which do not have at tertiary winding are written out as separate two winding records to the RAW format.
• File Formats: The RAW format does not allow a rectifier to be the voltage-controlling converter of multi-terminal DC line. Fixed so that when writing out the RAW file it forces the RAW file to show an inverter as the voltage-controlling converter.
• File Formats: Fixed potential error when saving to an earlier version of the PWB format related to the voltage-controlling bus of a multi-terminal DC line records.
• User Interface Dialogs: Fixed bug when displaying custom fields on object dialogs when the number of custom strings was not the same as the number of custom integers.
• User Interface Dialogs: Fixed potential access violation when deleting three-winding transformers and then choose to NOT delete the two-winding equivalent branches that represent the three-winding transformer.
• Oneline Diagrams: Fixed problems with switching to 3D mode in an embedded oneline when using keyboard shortcuts.
• Oneline Diagrams: Fixed omission where circuit breakers didn't display their orientation or style in the case info or AXD file.

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February 14, 2008

New Features

• Oneline Diagrams: Added ability on the Substation Dialog to apply the lat/long from the display objects
• Contingency Analysis: Added storage of the generator's regulated bus number to the reference state.
• Contingency Analysis: Modified the PostCTG Line Drop Compensation routine to change the regulated bus to the terminal bus if the XLDC_RCC value is less than or equal to 0.0002.
• Contingency Analysis: Added several messages to contingency solution to notify of generator record changes in the post-contingency solution regarding Line Drop Compensation, Maximum MW Response, AGC, and Participation Factor.
• Contingency Analysis: Modified contingency analysis dialog so that if a post-contigency auxiliary file is specified in the Advanced Modeling options and this file does not exist, then the contingency analysis will abort and prevent the user from executing the contingency analysis. An appropriate message is displayed.
• Contingency Analysis: Added the ability to properly monitor interfaces in both directions in the contingency analysis tool.
• PV and QV Curves: Modified QV Curve Options page so that the user can now set a check box to save or not save results to comma delimited text files. If the box is checked, but a file name is not specified, Simulator treats this the same as if the box is unchecked.
• Available Transfer Capability: Store the base case flow for elements monitored with ATC extra monitors. This should help to better estimate the flows on the extra monitored elements.

Bug Fixes

• File Formats: PowerWorld has seen more RAW ASCII files that include NULL (#0) characters. These characters should never appear in a modern text file, but we continue to see them from time to time. PowerWorld has modified the RAW file parsing routines to remove all NULL (#0) characters before reading the file.
• Auxiliary File: Fixed potential error if the syntax of an Auxiliary File was improperly terminated. Simulator will now gracefully fail when this occurs and notify you that the AUX file is bad.
• Oneline Diagrams: Fixed errors when loading in an older PWD file with Interface objects on a oneline diagram. The error resulted in flows arrows appear backwards on the interface object.
• Oneline Diagrams: If a keyboard shortcut is executed to open a oneline embedded within the currently active oneline and a oneline isn't currently active, now Simulator will chose to embed in the last active oneline.
• User Interface Dialogs: Fixed error that could occur when using the DC approximation and then trying to use an Injection Group to scale load or generation from the System Scaling Dialog.
• Contingency Analysis: Fixed potential bug when restoring the contingency reference state that might occur if a previous contingency modified the island records of the contingency. Bug could cause solution difficulties when a subsequent contingency involved a large generation or load outage.

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February 15, 2008

New Features

• None.

Bug Fixes

• Contingency Analysis: Fixed silly bug in February 14 patch regarding the Post-Contingency AUX file.

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February 16, 2008

New Features

• None.

Bug Fixes

• File Formats: When loading custom model expressions that refer to one another, sometimes the link from one custom expression to another would not be read in properly.  This has been fixed when reading from the PWB file as well as the AUX file.

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February 24, 2008

New Features

• Oneline Diagrams: Detecting a mouse click on an unfilled background ellipse was not working well when clicking on the left or right edge of the ellipse. This interaction has been improved.
• Contingency Analysis: Added more options for choosing to save a list of contingencies as an auxiliary file. Previously the normal Save As Aux methods were overridden to save a hard-coded list of fields as well as many other related objects. The normal Save As Aux choices now behave the same as other case information displays, while two new buttons have been added that save the more complete hard-coded set of objects and fields.
• Power Flow Solution: Improved solution performance for the situation where line X has just been CLOSED while at the same time Line Y has just been OPENED, if Line X and Line Y are in series with one another. Previously, angle smoothing was performed on the CLOSED line X in this situation which worked very poorly. This is now handled using a more appropriate voltage and angle estimation.
• Sensitivity Analysis: Added support for Injection Group objects for a field that shows the weighted average of the bus "Sensitivity\Injection dValue/dP" field. The weighting is based on the injection group participation factors.
• Sensitivity Analysis: Added a list of Injection Groups to the TLR/GSF dialog with the new field shown as a default column.

Bug Fixes

• File Formats: Fixed potential error when reading in old IEEE Common Format files.
• Case Information Displays: Fixed problem where it was possible to set the transformer nominal winding voltages and transformer base MVA to 0 in the case info displays. Doing so could cause floating point errors when trying to access or use the values in calculations. Simulator will no longer allow setting the values to 0 in the case infos, and will also detect and change values already stored as 0 in a PWB.
• Case Information Displays: Fixed the Limit Monitoring and Display Filter case information displays for Areas and Zones. Previously the customization of columns on these grids did not work completely correctly.
• Oneline Diagrams: If a transmission line was showing MVar flows flow out both ends or flowing into the line at both ends, then the flow arrow option for Minimum Pixel Size for flow arrows was being ignored on flow arrows in the middle of these lines. This has been fixed.

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March 12, 2008

New Features

• Auxiliary File Format: Added support for getting the multiple element TLR sensitivities by bus using the SaveData() script commands and the SimAuto calls.
• File Formats: Removed the prompt window regarding opening a blank oneline diagram when opening a case with no associated oneline diagram.
• File Formats: When reading GE EPC files, modified it to read multi-section line interface elements directly instead of assigning the element to the first or last section of the multi-section line.
• User Interface Dialogs: Modified the Run Mode Bus Dialog to show both the nominal and actual MW and Mvar values for bus shunts.
• User Interface Dialogs: Added storage to the Windows Registry of whether the main program window is Maximized and the forms position and size so that it is restored the next time the program is run.
• User Interface Dialogs: Added the name of the active case to the message log window.
  Oneline Diagrams: Modified the oneline links so that AXD files can be opened without the requirement of being in Edit Mode.
• Contingency Analysis: Made some new fields available on the Contingency Element case information displays that allow you to identify the elements by bus numbers and string IDs.

Bug Fixes

• File Formats: When reading in interface records from the GE EPC file format and then choosing to equivalence sections of multi-section line records, it was possible to lose some of the interface elements defined. This has been fixed.
• User Interface Dialogs: Fixed access violations that would occur after using the shortest path calculation.
• PV and QV Curve Tools: Properly set the minimum pu volt for constant power and current loads to 0 when doing the PV analysis. This had previously been done, but the option was getting set back to the original values between scenarios.
• PV and QV Curve Tools: Corrected variablename descriptions and types for fields associated with injection group ZIP factors and Q multiplier for power factor.
• Oneline Diagrams: When linking multi-section line display objects, set the number of sections equal to the linked object. This will prevent access violations if a display file is loaded with a different case in which the same multi-section line contains a different number of sections.
• Oneline Diagrams: Fixed bug that wasn't displaying the dynamic formatting correctly when using emphasis highlighting.
• Power Flow Solution: Fixed initialization of MW Control solution after loading a RAW or EPC file. Some changes made to the reference state in the February 14 patch might cause a problem when first trying to solve the case.
• Contingency Analysis: Fixed the handling of the combination of two contingency actions that acted on the same generator, load, or switched shunt. Specifying to close generator X, and then set its output to a value was not always working properly.

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March 26, 2008

New Features

• File Formats: When reading an entire case from a GE EPC file, if loads are encountered that have the same ID except that the alphabetical case is different, a unique ID will be assigned to the current load instead of only keeping the first load encountered in the file.
• Oneline Diagrams: Added option on the Draw Tab to choose Auto Insert > Reset Stub Locations... which will completely redo the positioning of objects anchored to buses and substations in the manner done when auto-inserting lines, gens, load, and shunts.
• Contingency Analysis: Added options to write out PTI CON files using bus name/kvs instead of bus numbers as well as ability to specify whether to truncate names to 8 or 12 characters.

Bug Fixes

• General: Fixed potential error that could occur if a power system consisted of a single loop of buses (such as a three bus system with three lines). Caused by new feature for power flow solution added on Feb 24.
• Auxiliary File Format: Fixed WriteTextToFile() script action to replace two doublequotes with a one doublequote after extracting. Done to allow a doublequotes in the text written to a file.
• Auxiliary File Format: Modified reading of script commands to properly error if you run across a doublequote " or left bracket [ immediately after reading in a string separated by doublequotes.
• Auxiliary File Format: Corrected problem with flow arrows being drawn in the wrong direction if updating a line from an AXD file and loading in the points in the opposite direction from what they had been previously defined.
• Case Information Displays: Removed extra sensitivity field from bus fields.
• Contingency Analysis: Fixed bug that would create a new contingency when renaming contingencies on the Contingency Definition dialog.
• Contingency Analysis: Fixed error when using DC solution and approximating VAR flows assuming constant voltage.

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April 16, 2008

New Features

• Case Information: On the Case Information Toolbar, the Filter List drop-down menu has been modified to place the list of filters in a submenu if there are more than 10 filters.
• Oneline Diagrams: When auto-inserting buses on the oneline diagram, a new option to insert using the substation's latitude/longitude coordinates has been added.
• PV and QV Curves: Increased the number of decimals saved to the Auxiliary File when saving the PV and QV Curve Tracking results.

Bug Fixes

• File Formats: Fixed potential error in processing a RAW file if one or both of the two title lines in the RAW file were blank.
• Oneline Diagrams: Removed the showing of oneline hints on unlinked elements.
• User Interface Dialogs: Fixed potential problem with the Edit Mode Switched Shunt dialog. After saving the switched shunt from this dialog, references to the switched shunt from injection group records or contingency elements could become unlinked.
• User Interface Dialogs: When opening the area dialog, the assignment of the Super Area was not working correctly. This was causing the super area assignment to be removed. This has been fixed.
• Power Flow Solution: When using the solution option to Disable Generator Mvar Limit Checking, Simulator was also not checking the Mvar limit of CONTINUOUS switched shunts that were being treated as PV buses.  This has been fixed.
• Available Transfer Capability: For the ATC EXtra Monitors, if the Relative Monitor Sensitivity Constant is set to zero, the ATC Extra Monitor sensitivity check is no longer done.
• PV and QV Curves: When using scripts or SimAuto to obtain the PV curve fields for "Worst Voltage Violation", the values were always being rounded to an integer. This has been fixed.
• PV and QV Curves: Fixed bug that was causing the script action PVWriteResultsAndOptions() to not function properly.

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April 25, 2008

New Features

• File Formats: Added the ability to read and write the PTI RAW version 31 format.
• Case Information: Added an explanation to the Paste button on the case information local menu if the Paste button is disabled. The button may say "key fields missing" or "object type invalid" if the first two lines of the clipboard are incorrect.
• Oneline Diagram: Modified the export to JPEG feature to include the contour color key if it is open.
• Power Flow Solution: Added restrictions to phase-shifter transformer movement in the power flow solution algorithm to restrict larger phase changes across a very small impedance phase-shifter. This helps with power flow convergence.

Bug Fixes

• Case Information Displays: When reading in filters from a PWB file, BETWEEN filter conditions that operated on integer fields (such as a bus numbers) were not properly read from the PWB file. The second comparison value was always being read as a zero. This has been fixed.
• Case Information Displays: Cleaned up errors related to new feature in previous patch for showing a filter drop-down menu if there were more than 10 filters.
• Case Information Displays: Fixed potential error when applying a switched shunt Advanced Filter to the bus records.
• Power Flow Solution: Fixed potential errors that could occur in the fast decoupled power flow as generators hit their minimum/maximum generator Mvar limits.
• Contingency Analysis: Fixed bug writing out PTI *.con contingency file. An extra quotation mark was being written sometimes.

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May 15, 2008

New Features

• Auxiliary Files: When unlinked model conditions are loaded from an auxiliary file or case, the message log now shows a warning.
• Contingency Analysis: Added a new field that can be added to a case information display showing Limit Violations. The field will show the violated element using labels if labels exist.
• Oneline Diagrams: Changed the circuit breaker objects to allow them to be dynamically formatted using colors.
• User Interface Dialogs: Modified to allow the lookup tables on the dynamic formatting dialog to be resized.
• Power Flow Solution: When dynamically assigning new slack buses, Simulator choose the bus that has the largest maximum generator MW output. This has been changed so that buses with more than 5000 MW are not chosen either because these likely represent generators with "9999" limits.

Bug Fixes

• Case Information Displays: Fixed some refresh errors on case information displays which would result in all the enterable colors appearing as black.
• Case Information Displays: When choose the Options drop-down on the Case Information Toolbar, some strange access violations errors could occur if the size of the Simulator window was small. This has been fixed.
• Case Information Displays: It was not possible to paste data into the Line Shunt Case Information Display because of conflicts between the column headings of Line Shunts and Branches. Changed the column headings on the Line Shunt object Status and ID columns so that they do not conflict with the Status and ID of the branch associated with the Line Shunt.
• Auxiliary Files: Removed a message log warning when reading in Advanced Filters which refered to another filter. The warning message was not valid.
• Contingency Analysis: There was a minor bug when defining a custom expression on the Contingency Violation List off the Combined Tables> dropdown. If you choose to have Simulator automatically add the column after defining the expression, the column was not correctly added.
• PV and QV Curves: Removed error message that would always be produced when saving out PV options from the dialog even when there was no error.
• User Interface Dialogs: Fixed potential access violation that could occur when in Floating Windows mode and opening the Dynamic Formatting dialog.
• General: Fixed a problem with the Lock and Key mechanism in Simulator which could cause the machine code to change thus requiring a new license key.

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May 19, 2008

New Features

• None.

Bug Fixes

• General: The name field of supplemental data records was not being trimmed of leading and trailing spaces. This was causing trouble when trying to use supplemental data records after populating them while reading in GIS Shapefiles. This has been fixed.

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May 22, 2008

New Features

• File Format: When choosing to Save a Case, the list of "Save as type" has been greatly shortened to make it easier to understand. To choose to save to the various RAW, EPC, or even older Simulator PWB formats, there are now single entries. An additional dialog then appears prompting you to which version of the particular type to save.
• File Format: When choosing to Save a Case, added new filetypes for saving as AUX using secondary keys or labels.
• Oneline Diagrams: made modification on coordinating whether to draw the colorkey form or not. Also modified so the color key can NOT be moved off the visible region of the oneline.

Bug Fixes

• Time Step Simulation: Corrections so that Schedules with Time Step Simulation can properly be saved and loaded from auxiliary files.
• Time Step Simulation: Changed TSB file format to save zone load information. This required the addition of a new TSB file version option called "from May 19, 2008 version 13 build or earlier". This version will not contain the zone load information that would cause errors if the file was read in a version earlier than the current patch.
• Time Step Simulation: Fixed access violation when loading in a time step custom results file that contains elements that are not in the current power flow case.
• Available Transfer Capability: When doing linearized DC contingency analysis that includes injection groups with Set To or Change By actions and doing merit order dispatch, the MW output value of associated generators was being inadvertently changed resulting in errors. This has been fixed.
• Available Transfer Capability: After loading in settings from an auxiliary file, the multiple scenario grids were not being refreshed to reflect the new data. This has been fixed.

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June 5, 2008

New Features

• Case Information Displays: Added support on the list of Advanced Filters display for deleting the advanced filters by right-clicking on a selection of filters.
• Oneline Diagrams: Added support for generator rotors spinning counter-clockwise by enter a negative number in angle change per refresh.
• Oneline Diagrams: When saving PWD files, Simulator previously saved a list of all Advanced Filters defined. The PWD file will now only save the list of filters that are used by the oneline diagrams Dynamic Formatting and Select By Criteria Sets.
• User Interface Dialogs: Added the automatic updating the three winding transformer impedance and tap values when the equivalent transformer values for impedance and tap are modified.
• PV and QV Curves: Added support for Custom Expressions in the QV results case information display.

Bug Fixes

• Auxiliary Files: Fixed error when saving a case as an Auxiliary file for transformers that had different Nom kV bases than the buses they were attached to. The impedances on the transformer base were being included in the AUX file when they should not have been.
• Oneline Diagrams: Fixed an error with defining a memo with a Screen Layer that corrupted PWD files. This feature was only available from the Screen Layer Dialog and will be removed for Version 13. It will be included in future versions of Simulator.
• PV and QV Curves: Fixed errors when loading in PV results from an auxiliary file because the "PVStudyName" was not being read correctly.
• PV and QV Curves: Fixed access violation that could occur when reading in a PV results AUX file that contained tracking for objects that could not be found in the power system case.

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June 13, 2008

New Features

• Contingency Analysis: Enhanced the linearized lossless contingency solution method and the DC approximation contingency solution method to handle all situations when islanding occurs as a result of the contingency.

Bug Fixes

• General: When opening a case by double-clicking on the *.PWB file in windows, Simulator would sometimes open with the Welcome appearing on top of the Simulator Window. The welcome screen could then not be closed. This has been fixed.
• General: Under some circumstances the Message Log window would become stuck behind the main Simulator Window. This form is supposed to remain on top while Simulator is active. This has been fixed.
• File Formats: When in opening a file of type "PTI RAW Data (with options)" while also being in RUN mode, Simulator did not immediately initialize some solution structures which could result in some extraneous error messages related to zero determinants. This has been fixed.
• File Formats: Modified reading of PTI RAW Two-Terminal DC Line records to maintain the DC Line Number identifier as read from the RAW file. Previously, Simulator would always assign Numbers starting from 1 up to the number of parallel DC Lines.
• File Formats: Fixed error that could occur when writing out a GE EPC file if there was a blank line in the case description.
• Case Information Displays: On the Injection Group Participation Point case information displays, the automatic recalculation of participation factors was occurring for participation points under some circumstances. This has been fixed.
• Case Information Displays: An access violation could occur when using a substation filter on a Bus Case Information Display. This has been fixed.
• Oneline Diagrams: Fixed access violation when loading in an AXD file and the orientation of a circuit breaker was blank.
• Oneline Diagrams: When opening a oneline diagram using "name/kv linking", if the name/kv of the device could not be found in the case, Simulator would keep the bus number read from the PWD file. This has been changed so that if the name/kv bus is not found, then the device is properly unlinked.
• Power Flow Solution: When closing in a line directly adjacent to a two-terminal DC transmission line, and then solving the case, an access violation would occur. This has been fixed.
• Available Transfer Capability: When loading in ATC results for multiple scenarios, if a limiting element did not exist and access violation would occur. This has been fixed and an appropriate message is sent to the log if element is missing from the case.
• SimAuto: Fixed bug in ChangeParametersMultipleElementFlatInput that caused errors for Matlab users trying to use this function through SimAuto

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June 23, 2008

New Features

• User Interface Dialogs: On the PTDF dialog, When clicking the button to "Visualize PTDFs", the pie chart oneline options are now changed to show PTDFs also. Previously only the flow arrows were changed.

Bug Fixes

• General: Fixed a problem with the Lock and Key mechanism in Simulator which could cause the machine code to change thus requiring a new license key.  This problem could occur on computers using a VPN Client.
• File Formats: When appending to a case using the PWB, RAW, or EPC file formats, an access violation could occur if MW Transactions were in the existing case. This has been fixed.
• Auxiliary File Formats: When writing out unlinked interface elements to an AUX file, extra quotations were being added around the unlinked string. This was then causing an error when loading back in the AUX file. This has been fixed.
• Oneline Diagrams: Increased the speed of renumbering buses on a oneline diagram
• Power Flow Solution: When using the DC approximation, if area tielines spanned two multi-terminal DC buses, the ACE calculation was performed incorrectly. This has been fixed.
• Power Flow Solution: Fixed a bug in parallel transformer tap balancing that occurred only for very unusual tap settings. If two parallel transformers had different step sizes with one being exactly 1/2 of the other, then tap balancing could cause osciallating taps.
• Time Step Simulation: Fixed problem reading in international Data/Time values for schedule subscriptions from an Auxiliary File.

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June 27, 2008

New Features

• File Formats: Added more error handling when reading EPC files to handle situations were AC branch, generator, load, or switched shunt ids were duplicated at a single bus or branch. It appears that the EPC file permits duplicate IDs if their upper/lower case is different. That EPC format also treats the circuit IDs " 1" the as different than "1 " (i.e. it treats the spaces as different IDs). Simulator now handles this but also creates new unique IDs as appropriate.  Messages are written to the log.

Bug Fixes

• File Formats: Fixed errors with the Edit Mode Tool "Append Case" that occurred when devices existed in both the existing case and the case that was being appended. This effected both RAW and EPC file appending.
• File Formats: When writing out EPC files, if multiple line shunts existed at the same end of a branch they were not being properly written to the EPC file. This has been fixed.
• File Formats: Fixed error when appending PWB files that contained MW transactions.
• Contingency Analysis: Fixed bug created by enhancement made on June 13 related to detecting islanding in the linearized contingency methods. This bug could cause slow solutions or errors in the SCOPF and ATC as well.
• Oneline Diagrams: Fixed error with reading in a DBF file as part of a shapefile/dbf file pair if the DBF file had date fields in it denoted by the "D" in the DBF file.
• General: When using the bus renumbering routine for the power flow case, the line shunt objects were not being properly updated to reflect the new bus numbers. This has been fixed.

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June 30, 2008

New Features

• Auxiliary File Format: Modified to automatically include any custom string, custom integer, custom float or memo field when saving hard-code auxiliary file formats. This is done only if at least one object uses these custom fields. Examples of this include saving the contingency analysis, ATC tool, PV tool and QV tool AUX files, as well as when choosing "Save Case As" with "files of type" being an AUX file.

Bug Fixes

• Contingency Analysis: Completed bug fix created by enhancement made on June 13 related to detecting islanding in the linearized contingency methods. This bug could cause slow solutions or errors in the SCOPF and ATC as well.

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July 2, 2008

New Features

• Available Transfer Capability: Added the ability to interact using Auxiliary files and SimAuto with the ATC Scenario Transfer Limitations by using the objecttype "TransferLimit". This is done by using fields ATCLineZoneChanges, ATCGenChanges, and ATCInterfaceChanges as integer identifier to specify the ATC Scenario the transfer limitations corresponds to. If these these Scenario keys are all blank or omitted from input data, then the limitations are assumed to go with the normal single set of ATC results.
• Available Transfer Capability: Added a new tab for multiple ATC Scenario results called "Combined Results". This shows a single case information display showing transfer limitations under ALL scenarios. Default columns for the fields ATCLineZoneChanges, ATCGenChanges, and ATCInterfaceChanges are included.

Bug Fixes

• Sensitivity Calculations: Starting with the June 23 patch, the PTDF dialog was not opening giving an error regarding "dxBarSubItemFilterBar". This has been fixed.
• Time Step Simulation: Corrected a bug that was setting the TSS TimeScale to 60 when the case opened a TSB file automatically.

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July 11, 2008

New Features

• Available Transfer Capability: Added script command ATCWriteToText(“filename”,filetype) where filetype can be TAB or CSV. If omitted, TAB is assumed. TAB will create a tab delimited file while CSV will create a comma delimited file. This script command is only used when writing the results from multiple ATC scenarios. The filename will be appended with the identifier for interface scenarios. If there are multiple interface scenarios, multiple files will be created.

Bug Fixes

• QV Curves: Correct system state was not being restored when output from the synchronous condenser was required to get an initial contingency solution. This could result in missing and/or incorrect results.
• QV Curves: QV results could not be filtered by creating an advanced filter. This has been fixed.
• User Interface Dialogs: Allow reactive capability curve point at 0 MW with both the Mvar minimum and maximum at this point set to 0. This was allowed if data was loaded in from an auxiliary file but it wasn’t permitted when making changes to the reactive capability curve from the generator dialog. This has been fixed.
• Auxiliary Files: Transformer parameters were not being read in the correct order from auxiliary files resulting in phase shifter information not being read in the correct units. This would only occur if a phase shifter was currently not defined as a phase shifter and was being set to a phase shifter via the auxiliary file. The problem with the incorrect units has been fixed.
• Power Flow Solution: Previously when the sum of Unspecified MW Interchanges do not sum to zero, Simulator will set the AGC Status to "Off AGC" for the area (or super area) to which an island slack bus belongs.  This has now been modified to only happen if the island involved includes multiple areas (or super areas).

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July 18, 2008

New Features

•  Oneline Diagrams: Added the ability to contour multi-section line objects. When contouring line objects, the contour image for a multi-section line will reflect the series of AC lines it represents. When contouring bus objects, locations of intermediate buses will be contoured.

Bug Fixes

• File Formats: The patch for appending files from June 27 introduced an error when reading in Areas from a RAW file. The area name and MW export amounts were not being read. This has been fixed.
• Oneline Diagrams: Fixed unusually slow auto-insertion When auto-inserting buses if there were more than one thousand buses at the same x/y or longitude/latitude coordinate.
• QV Curves: During the QV curve analysis if switched shunts that are on control exist at the curve bus, an attempt is made to have var support provided by the shunts in addition to the fake synchronous generator that is added at the bus to trace the curve. Sometimes during the process of determining how much support should be provided by the switched shunts, a seemingly infinite loop of power flow solutions could be entered. This could especially be a problem with continuous switched shunts. This has been fixed.
• PV Curves: During the PV analysis, the power flow solution options for Minimum pu Voltage for Constant Power and Constant Current Loads are set to 0. The solvability of the base case with the 0 setting for these options wasn’t properly being tested before going into the remainder of the analysis. This is now done properly and a message, “Base case could not be solved with special PV solution options”, will indicate that the process cannot continue because the base case cannot be solved with these options.

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August 8, 2008

New Features

• PV Curve Tool: Added the ability to specify merit order dispatch separately for the source and sink. This now allows you to use merit order for one and NOT the other.

Bug Fixes

• File Formats: The speed of writing out EPC or RAW files had been decreased in Version 13 especially when writing these files to a network hard-drive. This has been fixed and restored the speed of previous versions. The buffering when writing to text files was not working properly and has been fixed.
• Auxiliary Files: Fixed bug with allowing either comma or space delimiters in the SUBDATA section used to define points for background lines, transmission lines and other objects represent a graphical line

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August 18, 2008

New Features

• Case Information Displays: Added fields to display the three-winding transformer winding MVA base values.

Bug Fixes

• File Formats: When writing out three winding transformer impedances for the primary-tertiary or secondary-tertiary winding, if the MVA base for the winding was different than the MVA base for the primary-secondary winding, the impedance values were not written out correctly. This has been fixed.
• Contingency Analysis: When loading in ATC results from an auxiliary file, there was a bug that would create duplicate contingencies with no elements. This has been fixed.
• PV Curve Tool: Fixed bug when using merit order dispatch which caused difficulty when ramping out the transfer.

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September 8, 2008

New Features

• Time Step Simulation: Added Auxiliary File Support for Schedule Subscriptions
• Sensitivity Calculations: Added support for extracting the multiple element TLR sensitivity columns through SimAuto and through script commands

Bug Fixes

• Available Transfer Capability: Made correction to adding transfer limiters when both the max. number of elements and CTGs have been met.
• Case Information Displays and Auxiliary Files: Fixed problems setting the three winding transformer impedance parameters to new values in the string grid or from an aux file or script.

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September 18, 2008

New Features

• Case Information Displays: Modified to allow Paste from Clipboard operations on the Three-Winding transformer case information display.
• Auxiliary Files: In LoadAXD script if the oneline isn't already open, create a new oneline.
• Time Step Simulation: Added support for Time Step Simulation schedule subscriptions from DC Line fields.
• Time Step Simulation: Added support for saving schedule subscriptions to aux files, including fields from Generators bid points.

Bug Fixes

• None.

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September 26, 2008

New Features

• File Formats: Added error checking when reactive capability curve Min/Max values were flipped. If a user enters a "max=-500" and "min=+500" then Simulator will now automatically flip the values.
• Auxiliary Script Section: Added optional parameter AppendFile to ATCWriteResultsAndOptions. YES means results will be appended to an existing file. NO means existing file will be overwritten. Default is YES if not specified to retain previous functionality.

Bug Fixes

• File Formats: Fixed error reading RAW version 31 when there were FACTS devices in the FACTS data section
• User Interface Dialogs: When showing the reactive capability curves, the Y axis min/max values were being calculated based on the Min/Max Mvar output at 0.0 MW. For normal capability curves this was fine, but if the user made the Min/Max Mvar output very small at this point the curve was not drawn correctly.
• Oneline Diagrams: Fixed bug in which the memos in oneline diagrams were causing an access violation when being inserted. This only occurred in Vista systems.
• Oneline Diagrams: Corrected bug when loading in AXD file using secondary key fields if a transmission line has parallel circuits the circuit number wasn't being read so multiple lines were not being created.
• Power Flow Solution: When using PostCTG for the Line Drop Compensation, if a generator was operating at an extremely low per unit voltage (say < 0.3), then it was possible for the line drop to be impossible to implement. Error checking is done to prevent this generally, but was not being done for the PostCTG situation. This has been fixed.
• OPF Reserves: Fixed a couple of bugs in OPFR related to controls for regulation reserve down in zone constraints.

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October 15, 2008

New Features

• File Formats: When reading in transformer records from a RAW file, added the ability to read the FIXED tap on the to bus side. All values were previously read and converted to system base correctly, but the fixed tap was not maintained.
• File Formats: After reading an EPC file, Simulator will now go through and turn off control for all transformers that are more than 1/2 step size out of their Max/Min tap range.
• Case Information Displays: For branch objects, moved the fields for Transformer MVA Base and Transformer Nominal kV value inside the "Transformer Base" folder
• User Interface Dialogs: Modified the search that occurs when entering data into the choose object format by pasting text in.  It will now search to go to the nearest match when the search parameter is pasted.
• PV Curve Tool: When ramping in the PV curve tool, added the ability to specify ZIP components for Q (MVAR) load.
• PV Curve Tool: When ramping in the PV curve tool, added the ability to scale load in proportion to existing ZIP ratios.

Bug Fixes

• File Formats: After reading in a list of Model Conditions from an Auxiliary File, it is possible for no object to be referenced by the Model Condition. After then saving the case as a PWB file, there was an access violation when reading the PWB file back in. This has been fixed.
• File Formats: Fixed bug with assigning the ownership information for transformers When reading in transformer records from recent RAW files.
• Auxiliary File Script Section: Apply filter when getting list of PV results through SaveData and SaveDataWithExtra script commands. Filtering was working on the dialog just not through scripting. 

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October 20, 2008

New Features

• None.

Bug Fixes

• File Formats: Fixed bug introduced in October 15 patch.  When reading EPC transformer records we were disabling control of all transformers. 

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October 31, 2008

New Features

• File Formats: Added a new feature under the Records menu in the multi-section line case information display. This feature allows you to automatically renumber and name dummy buses of the multi-section line records.
• File Formats: Added a new option under the File Management tab on the Simulator Options dialog to reset the flag related to the regulated bus side for transformers. This is only needed when writing to EPC or RAW files.
• File Formats: Previously when reading from an EPC file Simulator would skip all records that did not contain ALL expect fields. It has now been modified to just skip the missing fields but still properly read the file.
• Sensitivity Calculations: Added a new tab for showing multi-element injection group sensitivities. The values show will be calculated from the bus values with weightings determined by the injection group participation factors.
• Oneline Diagrams: Changed printing so that the user can pick a particular DPI output to a printer. This allows onelines to be printed at printer resolution, not only screen resolution.
• PV and QV Curve Tool: Modification were made to the ZIP component scaling from the October 15 patch to better handle operating on nominal load values.

Bug Fixes

• General: Fixed some more problems that seem to be caused by the Matrox desktop management software.
• File Formats: Both RAW and EPC files contain a negative sign to signify whether the regulated bus is on the FROM or TO side of the transformer. Simulator does not need this because we always calculated a tap sensitivity when moving transformer taps. However, Simulator was not consistently managing this flag when reading from one format and then writing to a different format (e.g. load from RAW and then write to EPC). This has been fixed.
• Auxiliary Files: When loading branch records, error checking to prevent a branch whose from and to bus were the same has been added.
• User Interface Dialogs: When clicking to delete the First tab in the Model Explorer it would always remove the first entry in the Recent folder instead of the one being displayed. This has been fixed.
• Time Step Simulation: When loading in a list of Schedule Subscriptions, if the object did not exist in the case a dialog would appear. This dialog would appear for EVERY object that did not exist. This has been fixed so that messages are written to the log instead.
• Power Flow Solution: Simulator would not allow transactions between areas that did not belong to islands which were directly connected. This has been modified to properly allow transactions that traverse multiple islands.
• Oneline Diagram: Fixed potential access violation that could occur when removing too many vertices from a line.

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November 11, 2008

New Features

• Available Transfer Capability: Modfied the script command ATCWriteResultsAndOptions() to automatically save the case info DATAGRID settings relevant to ATC as well.

Bug Fixes

• File Formats: Cleaned up various errors with October 31 addition for renumbering and renaming dummy buses for multi-section lines.
• File Formats: Added checks throughout to make sure that for Switched Shunt records, the negative blocks come before the positive blocks. Simulator always considers negative blocks separately from positive, but when writing out blocks to RAW or EPC files the negative blocks must come first.
• Oneline Diagrams: Dramatically increased the speed of the option "Add Fields around Selection" When selecting a 1000s of objects.
• Oneline Diagrams: When showing a oneline using full screen, it was sometimes possible for the main PowerWorld window with the Ribbon and menus to appear on TOP of the full screen oneline. This has been fixed so that full screen onelines always force themselves to the top.
• PV and QV Curve Tool: Fixed interaction on the PV dialog that was causing user changes to the Identify Inadequate Voltage checkbox to not register properly.
• PV and QV Curve Tool: When choosing on the PV dialog to use a constant power factor without applying a Q multiplier, Simulator was not correctly forcing a Q multiplier of 1.0. This has been fixed.

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November 22, 2008

New Features

• Bus View Oneline: When customizing the bus view, modified to allow the user to define the field prefixes also.
• Case Information Displays: When saving to a CSV file we removed the automatic saving of some SUBDATA sections such as the interface elements.
• Case Information Displays: Added extra columns to MW Transactions to allow the import/export bid to be specified directly there.
• PV Curve Tool: Added support for advanced filtering on the PV plot form when selecting a list of objects.

Bug Fixes

• Case Information Displays: Fixed error that could occur when viewing the decoupled power flow matrices in Edit Mode.
• Case Information Displays: When loading in an auxiliary file which includes DATAGRID customizations, if the data grid was not already customized in Simulator the values would not be read properly. This has been fixed.
• Oneline Diagrams: Fixed an access violation that could occur when deleting a background object which belonged to a group.
• Oneline Diagrams: When opening a oneline diagram using the AXD file format in RUN mode, the oneline would be opened as editable. This has been fixed. Editing should only be allowed in run mode on the oneline.
• Fault Analysis: When performing an in-line fault, the oneline diagram is automatically updated to reflect the new bus added. An access violation occured if the transmission line was on the oneline diagram but the terminal buses were not drawn. This has been fixed.
• User Interface Dialogs: Fixed errors on the Three-Winding Transformer dialogs when specifying three-winding transformer parameters and then choosing to build the two-winding equivalents. This bug was related to the enhancements made in June to synchronize the three-winding and two-winding equivalent models.
• File Formats: Fixed potential error related to sorting switched shunt blocks.

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November 24, 2008

New Features

• Auxiliary Files: Added a new script command CalculateLODFMatrix. The format of the command is as follows.
  
  CalculateLODFMatrix(WhichOnes, filterProcess, filterMonitor, MonitorOnlyClosed, LinearMethod);
                      OUTAGES    ALL            ALL            YES or NO          DC or DCPS
                      CLOSURES   SELECTED       SELECTED
                                 AREAZONE       AREAZONE
                                 "filtername"   "filtername"
                                                SAME
  the LinearMethod parameter is optional. If not specified, the assume DC
   
• Auxiliary Files: Added a new script command SaveObjectFields. The format of the command is as follows.
  
  SaveObjectFields("filename", objecttype, [fieldlist]);
  
  Saves to filename, a CSV file which contains a list of all the fields available for objecttype
  The format of each line of the file is
  variablename, "field", "header", "description"
  variablename = represent those available for the objecttype
  "field" = the string you see when choosing the field from a drop-down menu
  "header" = the string you see in a column heading
  "description" = the string you see in hint windows regarding the field

Bug Fixes

• File Formats: Fixed error in the automatic detection of the RAW file version when loading in RAW files. This would make some earlier versions of RAW files appear to be version 29 files.
• File Formats: Fixed error that occured when reading the area records of a RAW file if the area record did not incdlue an area name.

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December 8, 2008

New Features

• Contingency Analysis: When loading an auxiliary file containing contingency definitions, if the contingency was savings using the Name_KV linking, an element may not be found if the name_kV values were repeated in the case. Modified it so that we search through all buses with a particular name_kV to see if a branch exists which connects appropriate buses.
• Time Step Simulation: Modified the TSB file format to save the start and end time points of a simulation
• User Interface Dialogs: When viewing topological differences with the Difference Flows tool and looking at Elements Removed, Name_NomKV field is now available and shown by default.
• User Interface Dialogs: Added option regarding whether to use Bus Numbers of Bus Name_NomKV when saving auxiliary files from the topological differences dialog.
• User Interface Dialogs: Modified the Advanced Filter Dialog so that when hitting the ENTER key while editing the comparison text it will act as though you clicked the Filter button.

Bug Fixes

• Auxiliary Files: When saving complete oneline to a display auxiliary file (AXD), we now save the views at the end of the file so that if a contour is applied to the current view it will be applied properly.
• User Interface Dialogs: Fixed error on the Three-Winding Transformer Dialog. When changing three winding XF nominal voltages or taps on this dialog, those values were not correctly saved and were not correctly reflected in the equivalent two winding XFs when creating the two winding equivalent transformers.
• Oneline Diagrams: If a line flow object was anchored to a line object and the from and to bus were not drawn on the oneline diagram, then the "auto-determine angle when anchored" feature of the line flow object was incorrectly flipping the arrows 180 degrees. This has been fixed.
• Oneline Diagrams: Fixed access violation errors that occurred when merging buses more than once on a oneline diagram.

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December 11, 2008

New Features

• None.

Bug Fixes

• File Format: Fixed a bug that could cause the PWB file to become corrupted if it was saved with unlinked elements in an injection group.
• PV Curve Tool: Fixed bug that could cause inconsistent results when using merit order dispatch.

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December 22, 2008

New Features

• None.

Bug Fixes

• File Format: Fixed error when reading EPC files if a tertiary bus was numbered zero (0).  Checks for non-existent tertiary bus were expecting a negative number.  This has been fixed.
• Oneline Diagrams: Fixed one more access violation errors that occurred when merging buses more than once on a oneline diagram.
• PV Curve Tool: Fixed bug that could occur if the terminal bus of the first participation point in an injection group was disconnected from the system.  This would result in the loss assignment during the PV ramping to show up on the system slack bus instead of being spread out amount the buyer.

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January 8, 2009

New Features

• None.

Bug Fixes

• File Format: When reading in EPC files, Simulator maintains extra GE data from the file. In the past this had included the transformer MVA Base, Voltage Bases, and Fixed Taps. These are now all stored with the Simulator data structures as well. When writing back out two-winding transformers to GE EPC files however, if the case had originally been read from an EPC file then Simulator was writing out the values that had been read with the GE Extra Data. If the values had not been edited this would not be noticed, but if changes were made in the transformer base values they would not be written out as changed.

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January 13, 2009

New Features

• None.

Bug Fixes

• General: If you have oneline diagrams open and then choose to open another case, there was an annoying access violation which occurred when closing the oneline diagrams.  This bug was introduced in the January 8 patch and has been fixed in this patch.

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January 14, 2009

New Features

• None.

Bug Fixes

• Power Flow: January 13 patch was causing the Post Power Flow Solution Actions to be skipped.  This has been fixed.

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February 3, 2009

New Features

• None.

Bug Fixes

• File Formats: For the GE EPC format, a problem was fixed with converting the min and max tap values when reading transformers with non-unity fixed taps on the FROM side of the transformer.
• Case Information Displays: The value for MW and Mvar losses shown on an Interface table were off by a factor of SBase. Thus for SBase=100, if losses were 1 MW, the interface showed 0.01 MW. This has been fixed.
• Oneline Diagrams: When reading contour setup information from an AXD file, the advanced filter referenced by a contour was not being properly read in. This has been fixed.
• Oneline Diagrams: Fixed access violation that would occur if terminately the drawing of a line by hitting the ENTER key instead of hitting DblClick.
• Memory: Fixed a potential problem with accessing owner summary information if changes were made while in Edit Mode and Run Mode was never entered.

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February 18, 2009

New Features

• None.

Bug Fixes

• Available Transfer Capability: Fixed access violation that could occur when viewing multiple scenarios results in the ATC dialog and then closing the dialog.
• Case Information: Fixed parsing of the area slack bus number/name string.
• User Interface Dialogs: Fixed potential errors in displaying the bus numbers in a drop-down box when bus numbers had more than 5 digits.
• User Interface Dialogs: The equations which were displayed on the dialog for specifying transformer taps and impedances on the transformer base were incorrect.  This image has been corrected.

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March 16, 2009

New Features

• Case Information Displays: For Owners, added field for showing MW and Mvar line loss. Also added storage of MW and Mvar line Loss with Difference Flows Base Case for Owners.
• Case Information Displays: For Injection Groups, added field for showing the weighted average MW Marg Cost of Energy, Congestion, and Losses.
• Case Information Displays: Added units for the MW and Mvar losses on an interface.
• Case Information Displays: Added Owners to the list of objects allowed for Model Conditions and Calculated Fields.

Bug Fixes

• File Formats: When writing out GE EPC files, current and power setpoints are calculated from the setpoints given to populate the EPC file.
• Oneline Diagrams: When right-clicking on an area field and choosing to show the Area Information Dialog, the dialog was not being shown. This has been fixed.
• Memory: When deleting a multi-terminal DC line record (whether manually, through a script, or through equivalencing), a memory access violation was occurring which corrupted the case. This has been fixed.

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March 23, 2009

New Features

• None.

Bug Fixes

• Contingency Analysis: When using the DC approximation (the DC Power Flow) with contingency analysis, the advanced contingency monitoring options were not being used. They are now included.

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April 8, 2009

New Features

• Bus View Oneline: Added ability when customizing the bus view to specify the Delta Per Mouse Click with fields so that the up/down arrow spinners are drawn appropriately.
• PV and QV Curve Tools: Added a check when running the PV Curve or the QV Curve tools to ensure that the Post-Contingency Auxiliary File exists. If the file is specified in the contingency analysis options but does not exist then the PV and QV curve will be aborted.
• Available Transfer Capability: When using the ATC method "Iterated Linear Step with Full CTG", added a check to ensure that the Post-Contingency Auxiliary File exists.

Bug Fixes

• User Interface Dialogs: Modified the equations on the dialog for specifying transformer impedances on the transformer base. The shunt terms are not effected by the fixed taps or nominal kV values.
• Contingency Analysis: Fixed errors with modeling Bus Outages which create islanded load and generation using the Linearized Contingency Analysis methods.

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April 9, 2009

New Features

• General: Added the ability to store in the Windows Registry whether the Ribbon is minimized and whether the Quick Access Toolbar is above or below the Ribbon.  This will then be remembered the next time you open Simulator.

Bug Fixes

• Case Information Displays: The drop-down button on Case Information toolbar which shows a list of available filters was broken in the patch released yesterday.  This has been fixed. This only effected that button and access to filters via right-click or the Filterbar was unaffected.

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April 14, 2009

New Features

• Auxiliary File Formats: When loading an auxiliary file format, if branch statuses are changed to close in a set of dead buses Simulator automatically makes a reasonable initial voltage guess for the newly energized buses. While most of the time this is helpful, if the AUX file also contained voltage phasor values for the buses, then the Simulator would override these values with our own estimate. This has been changed so that any bus for which the AUX file sets either voltage magnitude or angle will not have its voltage changed by our estimation routine.
• File Formats: Previously when loading an EPC file, only buses that had some online generation would set generator's AVR=NO in Simulator. This has been changed so that if there is no online generation, then the Mvar range for all offline generators is queried and all generators are set to AVR if the Mvar range is too small.
• Power Flow Solution: Improved transformer tap switching coordination in situations were a large number (> 50) transformers are trying to switch and a large number of those are stuck at the minimum or maximum tap or phase.

Bug Fixes

• Oneline Diagram: When adding an interface field to a oneline diagram on which no interface display objects are drawn a nuisance access violation would occur. This has been fixed.

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April 28, 2009

New Features

• None.

Bug Fixes

• Available Transfer Capability: When using the iterated steps in ATC and ramping of the base case state, if the power flow fails the step size is reduced by a factor of 2. After a successful solution the entire remaining desired step was attempted immediately. This has been changed so that the decreased step size is used instead until the desired step is achieve or the minimum step size is reached. This should speed up the ramping in bad situations.
• Contingency Analysis: Fixed nuisance access violation that occured on the Lines/Buses/Tranformers tab of the contingency analysis form when toggling the Selected or Skip field on the list of related contingency violations for each branch, interface or bus.
• Power Flow Solution: Fixed more minor errors related to ensuring that transformer taps do not get stuck at their limits.
• User Interface Dialogs: Modifed the scaling of loads to ensure that generators do not also scale if the generator scaling is set to 1.000. Previously if you were enforcing generator MW limits in the scaling, Simulator would automatically bring generator up/down to their limits and then scale other generators appropriately so the net generation change was zero.

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May 1, 2009

New Features

• Time Step Simulation: Add the ability to specify the default TSB file without a directory. This makes it possible to just look in the current working directory for the TSB. Also fixed the Excel save options to work accordingly

Bug Fixes

• File Formats: When loading in an EPC file, when Simulator encountered any status values that were not appropriate no error message was generated and the device behaved incorrectly. This was first noticed with a case that had a branch status of -4. To correct this, and status which is not 0, 1, (or 2 for branches) will always be treated as closed and a log message will appear stating this.
• Power Flow Solution: When all DC converters in a multi-terminal DC line had power or current setpoints of zero, Simulator would generate a log message saying there were no rectifiers or inverters found. The solution was fine but the log message was confusing and has been removed..

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May 6, 2009

New Features

• None.

Bug Fixes

• Contingency Analysis: When showing the  Present Value  for Interface MW Violations in contingency analysis, the values were displayed in per unit. This has been changed so values are displayed in MW instead.

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May 20, 2009

New Features

• File Formats: When reading RAW files, added additional error trapping when encountering a two character circuit or device identifier string which contained a single quote. The RAW file would contain the text [1,2,'2'',...] which does not conform with a CSV file that uses a single quote as a string encloser. To fix this, Simulator now looks for a string of text of the form '*'' and handles it appropriately.

Bug Fixes

• Security Contrained OPF: Fixed an error in the sensitivity calculations for generators connected to the system through parallel radial lines if a contingency was defined which outaged ONE of the lines. The generators were being treated as having zero sensitivity on the branch which remained in sensitivity and thus the overload could not be removed. This has been fixed.

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June 18, 2009

New Features

• Auxiliary Files Script Commands: Added a new RenumberMSLineDummyBuses("filename") script command which loads in a file with the new dummy bus numbers and new dummy names and makes changes. This new feature provides script acction to the option found with the multi-section line case information display.

Bug Fixes

• Memory: Fixed a rare access violation that sometimes occurs when opening or closing a case.

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June 25, 2009

New Features

• Power Flow Solution: When re-energizing an island by closing in a branch that connects the island to another energized island, Simulator estimates new voltages in the newly energized island before the power flow solution. A similar estimate has been added when energizing an island only by turning on generation in that island.

Bug Fixes

• None.

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July 2, 2009

New Features

• Auxiliary Files: It was not possible to apply the area/zone filters to the InterfaceElement lists. This has now been enabled.
• SimAuto: Added the ability to obtain the SCOPF Contingency Violations through the use of script commands and SimAuto

Bug Fixes

• Auxiliary Files: Using the area/zone filtering option on the Auxiliary File Export Format Description was not working properly. This has been fixed.

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August 10, 2009

New Features

• User Interface: When moving equipment by right-click on buses on the oneline diagram, the anchoring is not properly updated and deviced graphically moved to connect to their new buses as appropriate.

Bug Fixes

• File Formats: Fixed an access violation that could occur when writing out a RAW file if the name of the limit group "Default" was changed.
• File Formats: Fixed an access violation that could occur when writing out a RAW file if a switched shunt that was modeling a FACTS device was out of service.

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August 21, 2009

New Features

• None.

Bug Fixes

• General: When simultaneously executing multiple PowerWorld Simulator instances, it was possible for an error dialog to appear saying "Unable to save the license information. Please try again with administrator priviledges". This error dialog was not caused by priviledges but instead by the multiple Simulator trying to write to the same location simultaneously. This error dialog has been removed.

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New Features/Minor Improvements:

Select the desired item to view all New Features and Improvements since the release of Simulator 13

• File Formats
• Auxiliary Files (SCRIPT and DATA Sections)
• Simulator Automation Server (SimAuto)
• Case Information Displays 
• User Interface Dialogs
• Oneline Diagrams
• Bus View and Substation View Onelines
• Power Flow Solution
• Sensitivity Calculations
• Contingency Analysis Tool
• Time Step Simulation
• PV and QV Curve (PVQV) Tool
• Available Transfer Capability (ATC) Tool
• Optimal Power Flow (OPF) and Security Constrained OPF (SCOPF) Tool
• Security Constrained OPF (SCOPF) Tool
• OPF Reserves Tool
• Fault Analysis
• Help

  Top

File Formats

• (October 22, 2007) Modified the default behavior when reading a PTI RAW file. Simulator now estimate from the input data how the treatment of loads that belong to a different area than their terminal bus should be done in the area interchange equations.
• (January 4, 2008) Modified the reading of RAW files so that any comments found at the end of a line in the RAW file will be read into the corresponding record as the Memo Field. Memo are NOT written back out to the RAW file however.
• (March 12, 2007) Removed the prompt window regarding opening a blank oneline diagram when opening a case with no associated oneline diagram.
• (March 12, 2007) When reading GE EPC files, modified it to read multi-section line interface elements directly instead of assigning the element to the first or last section of the multi-section line.
• (March 26, 2008) When reading an entire case from a GE EPC file, if loads are encountered that have the same ID except that the alphabetical case is different, a unique ID will be assigned to the current load instead of only keeping the first load encountered in the file.
• (April 25, 2008) Added the ability to read and write the PTI RAW version 31 format.
• (May 22, 2008) When choosing to Save a Case, the list of "Save as type" has been greatly shortened to make it easier to understand. To choose to save to the various RAW, EPC, or even older Simulator PWB formats, there are now single entries. An additional dialog then appears prompting you to which version of the particular type to save.
• (May 22, 2008) When choosing to Save a Case, added new filetypes for saving as AUX using secondary keys or labels.
• (June 27, 2008) Added more error handling when reading EPC files to handle situations were AC branch, generator, load, or switched shunt ids were duplicated at a single bug. It appears that the EPC file permits duplicate IDs if their upper/lower case is different. That EPC format also treats the circuit IDs " 1" the as different than "1 " (i.e. it treats the spaces as different IDs). Simulator now handles this but also creates new unique IDs as appropriate. Messages are written to the log.
• (September 26, 2008) Added error checking when reactive capability curve Min/Max values were flipped. If a user enters a "max=-500" and "min=+500" then Simulator will now automatically flip the values.
• (October 15, 2008) When reading in transformer records from a RAW file, added the ability to read the FIXED tap on the to bus side. All values were previously read and converted to system base correctly, but the fixed tap was not maintained.
• (October 15, 2008) After reading an EPC file, Simulator will now go through and turn off control for all transformers that are more than 1/2 step size out of their Max/Min tap range.
• (October 31, 2008) Added a new feature under the Records menu in the multi-section line case information display. This feature allows you to automatically renumber and name dummy buses of the multi-section line records.
• (October 31, 2008) Added a new option under the File Management tab on the Simulator Options dialog to reset the flag related to the regulated bus side for transformers. This is only needed when writing to EPC or RAW files.
• (October 31, 2008) Previously when reading from an EPC file Simulator would skip all records that did not contain ALL expect fields. It has now been modified to just skip the missing fields but still properly read the file.
• (April 14, 2009) Previously when loading an EPC file, only buses that had some online generation would set generator's AVR=NO in Simulator. This has been changed so that if there is no online generation, then the Mvar range for all offline generators is queried and all generators are set to AVR if the Mvar range is too small.
• (May 20, 2009) When reading RAW files, added additional error trapping when encountering a two character circuit or device identifier string which contained a single quote. The RAW file would contain the text [1,2,'2'',...] which does not conform with a CSV file that uses a single quote as a string encloser. To fix this, Simulator now looks for a string of text of the form '*'' and handles it appropriately.

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Auxiliary Files (SCRIPT and DATA Sections)

• (October 5, 2007) On the Auxiliary File Export Format Description dialog, a button has been added to Create Format for Complete Case. This automatically creates a format description that is similar to that used by Simulator when choosing to Save Case, As Auxiliary File.
• (October 22, 2007) Fixed a potential bug that could occur when reading in an AUX file that created a two-terminal DC transmission line. The problem was that the transformer tap ratio was being read as zero causing a divide-by-zero error.
• (October 22, 2007) Modification throughout so that the Fault Analysis data can be read from an Auxiliary File format while in Edit Mode.
• (December 5, 2007) When saving out the limit monitorings settings, previously no information regarding specific voltage limits for specific buses was stored. This is now automatically added to the Limit Monitoring Auxiliary file when saved (this includes on the Limit Monitoring dialog as well as from the Contingency analysis, ATC, PV, QV, etc... AUX files.
• (December 12, 2007) Added a new script command CloseOneline("filename")
• (December 12, 2007) Added a new script command when running SimAuto called LoadAXD("AXDfilename", "onelinefilename", CreateIfNotFound)
• (January 4, 2008) Modified the CloseOneline() command so that if the name is empty, then Simulator closes the last focused oneline diagram.
• (March 12, 2008) Added support for getting the multiple element TLR sensitivities by bus using the SaveData() script commands and the SimAuto calls.
• (May 15, 2008) When unlinked model conditions are loaded from an auxiliary file or case, the message log now shows a warning.
• (June 30, 2008) Modified to automatically include any custom string, custom integer, custom float or memo field when saving hard-code auxiliary file formats. This is done only if at least one object uses these custom fields. Examples of this include saving the contingency analysis, ATC tool, PV tool and QV tool AUX files, as well as when choosing "Save Case As" with "files of type" being an AUX file.
• (September 18, 2008) In LoadAXD script if the oneline isn't already open, create a new oneline.
• (September 26, 2008) Added optional parameter AppendFile to ATCWriteResultsAndOptions. YES means results will be appended to an existing file. NO means existing file will be overwritten. Default is YES if not specified to retain previous functionality.
• (November 24, 2008) Added a new script command CalculateLODFMatrix. The format of the command is as follows.
  
  CalculateLODFMatrix(WhichOnes, filterProcess, filterMonitor, MonitorOnlyClosed, LinearMethod);
                      OUTAGES    ALL            ALL            YES or NO          DC or DCPS
                      CLOSURES   SELECTED       SELECTED
                                 AREAZONE       AREAZONE
                                 "filtername"   "filtername"
                                                SAME
  the LinearMethod parameter is optional. If not specified, the assume DC
   
• (November 24, 2008) Added a new script command SaveObjectFields. The format of the command is as follows.
  
  SaveObjectFields("filename", objecttype, [fieldlist]);
  
  Saves to filename, a CSV file which contains a list of all the fields available for objecttype
  The format of each line of the file is
  variablename, "field", "header", "description"
  variablename = represent those available for the objecttype
  "field" = the string you see when choosing the field from a drop-down menu
  "header" = the string you see in a column heading
  "description" = the string you see in hint windows regarding the field
• (April 14, 2009) When loading an auxiliary file format, if branch statuses are changed to close in a set of dead buses Simulator automatically makes a reasonable initial voltage guess for the newly energized buses. While most of the time this is helpful, if the AUX file also contained voltage phasor values for the buses, then the Simulator would override these values with our own estimate. This has been changed so that any bus for which the AUX file sets either voltage magnitude or angle will not have its voltage changed by our estimation routine.
• (June 18, 2009) Added a new RenumberMSLineDummyBuses ("filename") script command which loads in a file with the new dummy bus numbers and new dummy names and makes changes. This new feature provides script acction to the option found with the multi-section line case information display.
• (July 2, 2009) It was not possible to apply the area/zone filters to the InterfaceElement lists. This has now been enabled.

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Simulator Automation Server (SimAuto)

• (October 22, 2007) When using the command RunScriptCommand() in Simauto, Simulator previously would generate a temporary text file used in some internal routines. This empty text file would then be deleted after running the command. For some users, under some situations this file was being created by not deleted. Simulator has been changed so that this file is not longer needed.
• (November 15, 2007) Previously, when starting a SimAuto process, an existing Simulator instance would be taken over by the SimAuto process. This has been changed so that existing Simulator instances are left open and a new Simulator process is started by SimAuto.
• (July 2, 2009) Added the ability to obtain the SCOPF Contingency Violations through the use of script commands and SimAuto

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Case Information Displays 

• (October 5, 2007) Added new Fields Pane to the Model and Display Explorer giving direct access to the columns available for each case information display. You may left-click and drag fields onto the case information display to add fields.
• (October 5, 2007) Modified Case Information Displays so that holding down the CTRL key and then dragging a column heading allows you to move column order. You may also drag the field over to the new Fields Pane to remove it from the case information display.
• (October 5, 2007) Fixed a potential problem access violations that could occur when opening Display Explorer.
• (October 22, 2007) Added new case information displays to the Model Explorer to show Fault Analysis related information.
• (October 22, 2007) Modified the right-click menu "Insert" option on the Case Information Display so that it is still enabled when you right-click below the presently defined records.
• (November 13, 2007) Modified the drop-down list of Advanced Filters so that the active filter is indicated with a check-mark.
• (November 13, 2007) Started work on enhancing the plot columns feature. It now allows specification of color, line type, etc... for each column.
• (November 13, 2007) Modified the user interface throughout so that the "Use Area/Zone Filters" check-box is only available for objects to which these apply.
• (November 13, 2007) On the Area Case Information Display, added the "Area Slack Bus" as a default column
• (November 13, 2007) Increased the time that a hint is visible when hovering over a case information column from 2.5 seconds to 10.0 seconds.
• (November 13, 2007) Modified so that when opening a new Model Explorer the Explore Pane is always opened by default.
• (November 15, 2007) Added ability to copy/paste the fault analysis input parameters. Also gives ability to read/write from an Auxiliary File.
• (November 21, 2007) Fixed bug that was preventing the Area Slack Max MW field from being available.
• (November 21, 2007) Fixed bug with updating the Fields Pane when toggling between two case info displays that showed the SAME object types.
• (December 5, 2007) Added the ability to copy and paste sequence impedance data for branches.
• (December 5, 2007) Modified the list of fields for Limit Violations to group them in a logical manner aiding in the better understanding of what the fields mean.
• (January 28, 2008) Added many new fields that show a count of the number of generators, loads, branches, etc... that are contained by Areas, Zones, or Substations.
• (April 16, 2008) On the Case Information Toolbar, the Filter List drop-down menu has been modified to place the list of filters in a submenu if there are more than 10 filters.
• (April 25, 2008) Added an explanation to the Paste button on the case information local menu if the Paste button is disabled. The button may say "key fields missing" or "object type invalid" if the first two lines of the clipboard are incorrect.
• (June 5, 2008) Added support on the list of Advanced Filters display for deleting the advanced filters by right-clicking on a selection of filters.
• (August 18, 2008) Added fields to display the three-winding transformer winding MVA base values.
• (September 18, 2008) Modified to allow Paste from Clipboard operations on the Three-Winding transformer case information display.
• (October 15, 2008) For branch objects, moved the fields for Transformer MVA Base and Transformer Nominal kV value inside the "Transformer Base" folder
• (November 22, 2008) When saving to a CSV file we removed the automatic saving of some SUBDATA sections such as the interface elements.
• (November 22, 2008) Added extra columns to MW Transactions to allow the import/export bid to be specified directly there.
• (March 16, 2009) For Owners, added field for showing MW and Mvar line loss. Also added storage of MW and Mvar line Loss with Difference Flows Base Case for Owners.
• (March 16, 2009) For Injection Groups, added field for showing the weighted average MW Marg Cost of Energy, Congestion, and Losses.
• (March 16, 2009) Added units for the MW and Mvar losses on an interface.
• (March 16, 2009) Added Owners to the list of objects allowed for Model Conditions and Calculated Fields.

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User Interface Dialogs

• (October 5, 2007) Added the File Menu to the Onelines Ribbon Tab so that buttons on that menu can be added to the Quick Access Toolbar.
• (November 13, 2007) On the Interface Dialog, add the weighting column by default to the Interface Element Grid.
• (November 13, 2007) When inserting a bus graphically on a oneline diagram, modifications were made to provide better feedback on the the Bus dialog as to whether or not a new bus is being added to the power system model.
• (November 13, 2007) Added ability to Tile Horizontally or Tile Vertically. This is available from the Windows Ribbon Tab.
• (November 13, 2007) Added Difference Flows Menu to the Case Data Ribbon Group on the Case Information Ribbon Tab.
• (March 12, 2008) Modified the Run Mode Bus Dialog to show both the nominal and actual MW and Mvar values for bus shunts.
• (March 12, 2008) Added storage to the Windows Registry of whether the main program window is Maximized and the forms position and size so that it is restored the next time the program is run.
• (March 12, 2008) Added the name of the active case to the message log window.
• (May 15, 2008) Modified to allow the lookup tables on the dynamic formatting dialog to be resized.
• (June 5, 2008) Added the automatic updating the three winding transformer impedance and tap values when the equivalent transformer values for impedance and tap are modified.
• (June 23, 2008) On the PTDF dialog, When clicking the button to "Visualize PTDFs", the pie chart oneline options are now changed to show PTDFs also. Previously only the flow arrows were changed.
• (October 15, 2008) Modified the search that occurs when entering data into the choose object format by pasting text in.  It will now search to go to the nearest match when the search parameter is pasted.
• (December 8, 2008) When viewing topological differences with the Difference Flows tool and looking at Elements Removed, Name_NomKV field is now available and shown by default.
• (December 8, 2008) Added option regarding whether to use Bus Numbers of Bus Name_NomKV when saving auxiliary files from the topological differences dialog.
• (December 8, 2008) Modified the Advanced Filter Dialog so that when hitting the ENTER key while editing the comparison text it will act as though you clicked the Filter button.
• (April 9, 2009) Added the ability to store in the Windows Registry whether the Ribbon is minimized and whether the Quick Access Toolbar is above or below the Ribbon. This will then be remembered the next time you open Simulator.
• (August 10, 2009) When moving equipment by right-click on buses on the oneline diagram, the anchoring is not properly updated and deviced graphically moved to connect to their new buses as appropriate.

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Oneline Diagrams

• (October 5, 2007) When manually drawing generator, load, and switched shunt objects on a substation-based diagram, Simulator now properly determines which substation is closest to where you click.
• (October 5, 2007) The refreshing of anchors of generator, load, and switched shunt objects on a substation-based diagram has been modified to properly anchor to the substation.
• (October 5, 2007) Increased the speed of refreshing anchors when done by toggling the Anchored checkbox on the Format Dialog.
• (October 22, 2007) Added several pre-defined border Sets on the Auto-Insert Borders dialog.
• (December 5, 2007) Adding support for showing Geo-Data View oneline objects in 3D.
• (January 28, 2008) Modified the oneline links so that they can also open Display Auxiliary Files (AXD)
• (February 14, 2008) Added ability on the Substation Dialog to apply the lat/long from the display objects.
• (February 24, 2008) Detecting a mouse click on an unfilled background ellipse was not working well when clicking on the left or right edge of the ellipse. This interaction has been improved.
• (March 12, 2007) Modified the oneline links so that AXD files can be opened without the requirement of being in Edit Mode.
• (March 26, 2008) Added option on the Draw Tab to choose Auto Insert > Reset Stub Locations... which will completely redo the positioning of objects anchored to buses and substations in the manner done when auto-inserting lines, gens, load, and shunts.
• (April 16, 2008) When auto-inserting buses on the oneline diagram, a new option to insert using the substation's latitude/longitude coordinates has been added.
• (April 25, 2008) Modified the export to JPEG feature to include the contour color key if it is open.
• (May 15, 2008) Changed the circuit breaker objects to allow them to be dynamically formatted using colors.
• (May 22, 2008) made modification on coordinating whether to draw the colorkey form or not. Also modified so the color key can NOT be moved off the visible region of the oneline.
• (June 5, 2008) Added support for generator rotors spinning counter-clockwise by enter a negative number in angle change per refresh.
• (June 5, 2008) When saving PWD files, Simulator previously saved a list of all Advanced Filters defined. The PWD file will now only save the list of filters that are used by the oneline diagrams Dynamic Formatting and Select By Criteria Sets.
• (July 18, 2008) Added the ability to contour multi-section line objects. When contouring line objects, the contour image for a multi-section line will reflect the series of AC lines it represents. When contouring bus objects, locations of intermediate buses will be contoured.
• (October 31, 2008) Changed printing so that the user can pick a particular DPI output to a printer. This allows onelines to be printed at printer resolution, not only screen resolution.

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Bus View and Substation View Onelines

• (November 13, 2007) Brought back a feature that allows the graphical insertion of new generators, loads, or switched shunts on a Bus View. This was removed in an earlier patch due to a bug that has now been fixed.
• (November 22, 2008) When customizing the bus view, modified to allow the user to define the field prefixes also.
• (April 8, 2009) Added ability when customizing the bus view to specify the Delta Per Mouse Click with fields so that the up/down arrow spinners are drawn appropriately.

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Power Flow Solution

• (December 12, 2007) Made some minor changes to help speed up the power flow solution.
• (February 24, 2008) Improved solution performance for the situation where line X has just been CLOSED while at the same time Line Y has just been OPENED, if Line X and Line Y are in series with one another. Previously, angle smoothing was performed on the CLOSED line X in this situation which worked very poorly. This is now handled using a more appropriate voltage and angle estimation.
• (April 25, 2008) Added restrictions to phase-shifter transformer movement in the power flow solution algorithm to restrict larger phase changes across a very small impedance phase-shifter. This helps with power flow convergence.
• (May 15, 2008) When dynamically assigning new slack buses, Simulator choose the bus that has the largest maximum generator MW output. This has been changed so that buses with more than 5000 MW are not chosen either because these likely represent generators with "9999" limits.
• (April 14, 2009) Improved transformer tap switching coordination in situations were a large number (>50) transformers are trying to switch and a large number of those are stuck at the minimum or maximum tap or phase.

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Sensitivity Calculations

• (February 24, 2008) Added support for Injection Group objects for a field that shows the weighted average of the bus "Sensitivity\Injection dValue/dP" field. The weighting is based on the injection group participation factors.
• (February 24, 2008) Added a list of Injection Groups to the TLR/GSF dialog with the new field shown as a default column.
• (September 8, 2008) Added support for extracting the multiple element TLR sensitivity columns through SimAuto and through script commands
• (October 31, 2008) Added a new tab for showing multi-element injection group sensitivities. The values show will be calculated from the bus values with weightings determined by the injection group participation factors.

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Contingency Analysis Tool

• (November 13, 2007) Changed the default for future cases so that the Contingency Analysis Make Up Power uses the option "Generator Participation Factors From Entire Case Directly"
• (November 13, 2007) Added a new column for Aggregate MW Overload caused by a particular contingency.
• (November 21, 2007) Previously the auto-insertion of contingencies routine did not allow the auto-insertion of Generator or Bus outages at the slack bus. Simulator actually handles this outage fine, so the restriction of the auto-insertion has been removed.
• (December 5, 2007) The list of contingencies inside Simulator previously was not sorted alphabetically by name. For contingencies lists shorter than about 5,000 this was fine, however some users are starting to define contingency lists in excess of 500,000 contingencies. This was causing huge performance problems in interacting with the model. The contingency list now maintains a sorted internal list so that lookups of contingencies by name are much faster allowing for much larger contingencies lists to be defined.
• (December 5, 2007) Changed the user-interaction with the Contingency Definition Dialog to not use a drop-down box anymore. Drop-downs to not work for very long lists of objects.
• (December 7, 2007) Added the ability to define special inclusion and exclusion monitoring lists of elements with each contingency. This allows you to NOT monitor specific elements, or to monitor only a specific list of elements. For Version 13, this feature is now available, but you will not be able to store these specifications with the PWB format until version 14.
• (December 12, 2007) Optimized the calculations done for Linearized Contingency Analysis to speed them up substantially. Linearized contingency analysis should now run approximately 3 times faster.
• (December 12, 2007) When using make-up power in the contingency analysis tool, the generation make-up loop was using a very low tolerance (4 times the mismatch solution tolerance). This was causing solution times to be much slower than desirable. We have changed this tolerance to be 5 MW instead now which for typical single-line outages results in a contingency solution speed between 2 and 3 times faster.
• (December 19, 2007) Added new option for the Make Up Power AGC Tolerance on the Contingency Analysis dialog.
• (December 19, 2007) Added ability to filter the contingency analysis records by Branch, Generator, Load, Switched Shunt, Interface, Injection Group or DC LIne. A Contingency record will meet the filter if it contains any of these objects in its element actions that meet their filter.
• (February 14, 2008) Added storage of the generator's regulated bus number to the reference state.
• (February 14, 2008) Modified the PostCTG Line Drop Compensation routine to change the regulated bus to the terminal bus if the XLDC_RCC value is less than or equal to 0.0002 (ZBRThres).
• (February 14, 2008) Added several messages to contingency solution to notify of generator record changes in the post-contingency solution regarding Line Drop Compensation, Maximum MW Response, AGC, and Participation Factor.
• (February 14, 2008) Modified contingency analysis dialog so that if a post-contigency auxiliary file is specified in the Advanced Modeling options and this file does not exist, then the contingency analysis will abort and prevent the user from executing the contingency analysis. An appropriate message is displayed.
• (February 14, 2008) Added the ability to properly monitor interfaces in both directions in the contingency analysis tool.
• (February 24, 2008) Added more options for choosing to save a list of contingencies as an auxiliary file. Previously the normal Save As Aux methods were overridden to save a hard-coded list of fields as well as many other related objects. The normal Save As Aux choices now behave the same as other case information displays, while two new buttons have been added that save the more complete hard-coded set of objects and fields.
• (March 12, 2008) Made some new fields available on the Contingency Element case information displays that allow you to identify the elements by bus numbers and string IDs.
• (March 26, 2008) Added options to write out PTI CON files using bus name/kvs instead of bus numbers as well as ability to specify whether to truncate names to 8 or 12 characters.
• (May 15, 2008) Added a new field that can be added to a case information display showing Limit Violations. The field will show the violated element using labels if labels exist.
• (June 13, 2008) Enhanced the linearized lossless contingency solution method and the DC approximation contingency solution method to handle all situations when islanding occurs as a result of the contingency.
• (December 8, 2008) When loading an auxiliary file containing contingency definitions, if the contingency was savings using the Name_KV linking, an element may not be found if the name_kV values were repeated in the case. Modified it so that we search through all buses with a particular name_kV to see if a branch exists which connects appropriate buses.

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Time Step Simulation

• (December 5, 2007) Added support for showing the Case Information Toolbar on the Time Step Simulation dialog.
• (September 8, 2008) Added Auxiliary File Support for Schedule Subscriptions
• (September 18, 2008) Added support for Time Step Simulation schedule subscriptions from DC Line fields.
• (September 18, 2008) Added support for saving schedule subscriptions to aux files, including fields from Generators bid points.
• (December 8, 2008) Modified the TSB file format to save the start and end time points of a simulation
• (May 1, 2009) Add the ability to specify the default TSB file without a directory. This makes it possible to just look in the current working directory for the TSB. Also fixed the Excel save options to work accordingly

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PV and QV Curve (PVQV) Tool

• (February 14, 2008) Modified QV Curve Options page so that the user can now set a check box to save or not save results to comma delimited text files. If the box is checked, but a file name is not specified, Simulator treats this the same as if the box is unchecked.
• (April 16, 2008) Increased the number of decimals saved to the Auxiliary File when saving the PV and QV Curve Tracking results.
• (June 5, 2008) Added support for Custom Expressions in the QV results case information display.
• (August 8, 2008) Added the ability to specify merit order dispatch separately for the source and sink. This now allows you to use merit order for one and NOT the other.
• (October 15, 2008) When ramping in the PV curve tool, added the ability to specify ZIP components for Q (MVAR) load.
• (October 15, 2008) When ramping in the PV curve tool, added the ability to scale load in proportion to existing ZIP ratios.
• (October 31, 2008) Modification were made to the ZIP component scaling from the October 15 patch to better handle operating on nominal load values.
• (November 22, 2008) Added support for advanced filtering on the PV plot form when selecting a list of objects.
• (April 8, 2009) Added a check when running the PV Curve or the QV Curve tools to ensure that the Post-Contingency Auxiliary File exists. If the file is specified in the contingency analysis options but does not exist then the PV and QV curve will be aborted.

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Available Transfer Capability (ATC) Tool

• (October 5, 2007) Added new field to transfer limiter results that shows the unaltered MVA limit that is defined with a monitored element.
• (October 5, 2007) When running iterated ATC methods, ramping transfer, or moving to one of the multiple scenarios, the minimum voltages for reducing load are set to 0.
• (February 14, 2008) Store the base case flow for elements monitored with ATC extra monitors. This should help to better estimate the flows on the extra monitored elements.
• (July 2, 2008) Added the ability to interact using Auxiliary files and SimAuto with the ATC Scenario Transfer Limitations by using the objecttype "TransferLimit". This is done by using fields ATCLineZoneChanges, ATCGenChanges, and ATCInterfaceChanges as integer identifier to specify the ATC Scenario the transfer limitations corresponds to. If these these Scenario keys are all blank or omitted from input data, then the limitations are assumed to go with the normal single set of ATC results.
• (July 2, 2008) Added a new tab for multiple ATC Scenario results called "Combined Results". This shows a single case information display showing transfer limitations under ALL scenarios. Default columns for the fields ATCLineZoneChanges, ATCGenChanges, and ATCInterfaceChanges are included.
• (July 11, 2008) Added script command ATCWriteToText(“filename”,filetype) where filetype can be TAB or CSV. If omitted, TAB is assumed. TAB will create a tab delimited file while CSV will create a comma delimited file. This script command is only used when writing the results from multiple ATC scenarios. The filename will be appended with the identifier for interface scenarios. If there are multiple interface scenarios, multiple files will be created.
• (November 11, 2008) Modfied the script command ATCWriteResultsAndOptions() to automatically save the case info DATAGRID settings relevant to ATC as well.
• (April 8, 2009) When using the ATC method "Iterated Linear Step with Full CTG", added a check to ensure that the Post-Contingency Auxiliary File exists.

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Optimal Power Flow (OPF)

• (November 13, 2007) Cleaned up the graying out of Area fields related to the OPF options to make them consistent and provide better feedback as to why they are disabled.

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Security Constrained OPF (SCOPF) Tool

• (November 21, 2007) On the Price Details case information display, modified so that the column headings regarding contingency violations include the name of the contingency also.
• (May 20, 2009) Fixed an error in the sensitivity calculations for generators connected to the system through parallel radial lines if a contingency was defined which outaged ONE of the lines. The generators were being treated as having zero sensitivity on the branch which remained in sensitivity and thus the overload could not be removed. This has been fixed.

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OPF Reserves Tool

• (November 13, 2007) Added support for doing Difference Flows comparisons of the OPF Reserve results

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Fault Analysis

• (November 13, 2007) Added the Case Information Toolbar to the Fault Analysis Dialog.
• (January 28, 2008) Simulator defaults all zero-sequence parameters for transmission line to be equal to 2.5 times the positive sequence impedances. Simulator continued this behavior when reading in PTI Sequence files, but it appears that PTI assumes that lines are open in the zero-sequence model if no zero-seqpence data is specified in the *.seq data file. When reading *.seq Simulator now gives the user the ability to assume this behavior.

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Help

• No new features yet

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Bug Fixes:

• General
• File Formats
• Auxiliary Files (SCRIPT and DATA Sections)
• Simulator Automation Server (SimAuto)
• Case Information Displays 
• User Interface Dialogs
• Oneline Diagrams
• Bus View and Substation View Onelines
• Power Flow Solution
• Sensitivity Calculations
• Contingency Analysis Tool
• Time Step Simulation
• PV and QV Curve (PVQV) Tool
• Available Transfer Capability (ATC) Tool
• Optimal Power Flow (OPF)
• Security Constrained OPF (SCOPF) Tool
• OPF Reserves Tool
• Fault Analysis
• Memory

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General

• (December 5, 2007) The Lock and Key mechanism in Simulator relies on the Windows Management Instrumentation (WMI) part of the windows operating system. On rare occasions users were experiencing errors in their WMI installation and as a result the software could not be executed. Fixes have been made to allow the lock/key mechanism to work under these situations, though PowerWorld still recommends fixing the windows installation to ensure the WMI will work properly.
• (March 26, 2008) Fixed potential error that could occur if a power system consisted of a single loop of buses (such as a three bus system with three lines). Caused by new feature for power flow solution added on Feb 24.
• (May 15, 2008) Fixed a problem with the Lock and Key mechanism in Simulator which could cause the machine code to change thus requiring a new license key.
• (May 19, 2008) The name field of supplemental data records was not being trimmed of leading and trailing spaces. This was causing trouble when trying to use supplemental data records after populating them while reading in GIS Shapefiles. This has been fixed.
• (June 13, 2008) When opening a case by double-clicking on the *.PWB file in windows, Simulator would sometimes open with the Welcome appearing on top of the Simulator Window. The welcome screen could then not be closed. This has been fixed.
• (June 13, 2008) Under some circumstances the Message Log window would become stuck behind the main Simulator Window. This form is supposed to remain on top while Simulator is active. This has been fixed.
• (June 23, 2008) Fixed a problem with the Lock and Key mechanism in Simulator which could cause the machine code to change thus requiring a new license key. This problem could occur on computers using a VPN Client.
• (June 27, 2008) When using the bus renumbering routine for the power flow case, the line shunt objects were not being properly updated to reflect the new bus numbers. This has been fixed.
• (October 31, 2008) Fixed some more problems that seem to be caused by the Matrox desktop management software.
• (January 13, 2009) If you have oneline diagrams open and then choose to open another case, there was an annoying access violation which occurred when closing the oneline diagrams.  This bug was introduced in the January 8 patch and has been fixed in this patch.
• (August 21, 2009) When simultaneously executing multiple PowerWorld Simulator instances, it was possible for an error dialog to appear saying "Unable to save the license information. Please try again with administrator priviledges". This error dialog was not caused by priviledges but instead by the multiple Simulator trying to write to the same location simultaneously. This error dialog has been removed.

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File Formats

• (October 5, 2007) Fixed a bug in writing out the fixed tap ratio on the secondary and/or tertiary windings of a three-winding transformer if the transformer nominal voltage base was different than the bus nominal voltage.
• (October 11, 2007) Fixed bug that would make it impossible to save a PWB file after applying an advanced sort to the Area Reporting or Zone Reporting case information displays on the Limit Monitoring Settings Dialog.
• (November 13, 2007) Fixed bug writing out reactive capability curves in the Q table data section to the EPC file format.
• (November 13, 2007) If any transient stability models were defined for a generator, the ability to Append to the case was not working properly. This has been fixed.
• (November 21, 2007) A bug was introduced in Simulator 13 when writing out PWD oneline files out to version 12 or earlier PWD versions. This bug has been fixed in Version 13, and a fix has also been added to Simulator 12.0 to allow it to gracefully read the PWD files even if they were written incorrectly.
• (December 12, 2007) Fixed potential bug when reading in a PWB file that contained multi-section lines.
• (December 19, 2007) Modified the writing of GE EPC files so that the Generator MVar output is written to 2 decimal places instead of 1.
• (January 4, 2008) Fixed an error when loading in Advanced Filter Conditions that contained more than one value (such as the between comparisons)
• (January 28, 2008) When reading in PWB files with custom fields defined, Simulator was not always properly updating the Custom Field Descriptions to include the number of values specified. This has been fixed.
• (February 6, 2008) The EPC and RAW file formats have no indication for a generator of "AVR = NO". To replicate this behavior, PowerWorld now writes out the Min/Max VAR of such a generator to be equal to the present Mvr output of the generator.
• (February 6, 2008) The RAW format does not support three-winding transformers without a tertiary winding. Fixed error so that three-winding transformers which do not have at tertiary winding are written out as separate two winding records to the RAW format.
• (February 6, 2008) The RAW format does not allow a rectifier to be the voltage-controlling converter of multi-terminal DC line. Fixed so that when writing out the RAW file it forces the RAW file to show an inverter as the voltage-controlling converter.
• (February 6, 2008) Fixed potential error when saving to an earlier version of the PWB format related to the voltage-controlling bus of a multi-terminal DC line records.
• (February 14, 2008) PowerWorld has seen more RAW ASCII files that include NULL (#0) characters. These characters should never appear in a modern text file, but we continue to see them from time to time. PowerWorld has modified the RAW file parsing routines to remove all NULL (#0) characters before reading the file.
• (February 16, 2008) When loading custom model expressions that refer to one another, sometimes the link from one custom expression to another would not be read in properly.  This has been fixed when reading from the PWB file as well as the AUX file.
• (February 24, 2008) Fixed potential error when reading in old IEEE Common Format files.
• (March 12, 2008) When reading in interface records from the GE EPC file format and then choosing to equivalence sections of multi-section line records, it was possible to lose some of the interface elements defined. This has been fixed.
• (April 16, 2008) Fixed potential error in processing a RAW file if one or both of the two title lines in the RAW file were blank.
• (June 13, 2008) When in opening a file of type "PTI RAW Data (with options)" while also being in RUN mode, Simulator did not immediately initialize some solution structures which could result in some extraneous error messages related to zero determinants. This has been fixed.
• (June 13, 2008) Modified reading of PTI RAW Two-Terminal DC Line records to maintain the DC Line Number identifier as read from the RAW file. Previously, Simulator would always assign Numbers starting from 1 up to the number of parallel DC Lines.
• (June 13, 2008) Fixed error that could occur when writing out a GE EPC file if there was a blank line in the case description.
• (June 23, 2008) When appending to a case using the PWB, RAW, or EPC file formats, an access violation could occur if MW Transactions were in the existing case. This has been fixed.
• (June 27, 2008) Fixed errors with the Edit Mode Tool "Append Case" that occurred when devices existed in both the existing case and the case that was being appended. This effected both RAW and EPC file appending.
• (June 27, 2008) When writing out EPC files, if multiple line shunts existed at the same end of a branch they were not being properly written to the EPC file. This has been fixed.
• (June 27, 2008) Fixed error when appending PWB files that contained MW transactions.
• (July 18, 2008) The patch for appending files from June 27 introduced an error when reading in Areas from a RAW file. The area name and MW export amounts were not being read. This has been fixed.
• (August 8, 2008) The speed of writing out EPC or RAW files had been decreased in Version 13 especially when writing these files to a network hard-drive. This has been fixed and restored the speed of previous versions. The buffering when writing to text files was not working properly and has been fixed.
• (August 18, 2008) When writing out three winding transformer impedances for the primary-tertiary or secondary-tertiary winding, if the MVA base for the winding was different than the MVA base for the primary-secondary winding, the impedance values were not written out correctly. This has been fixed.
• (September 26, 2008) Fixed error reading RAW version 31 when there were FACTS devices in the FACTS data section
• (October 15, 2008) After reading in a list of Model Conditions from an Auxiliary File, it is possible for no object to be referenced by the Model Condition. After then saving the case as a PWB file, there was an access violation when reading the PWB file back in. This has been fixed.
• (October 15, 2008) Fixed bug with assigning the ownership information for transformers When reading in transformer records from recent RAW files.
• (October 20, 2008) Fixed bug introduced in October 15 patch.  When reading EPC transformer records we were disabling control of all transformers.
• (October 31, 2008) Both RAW and EPC files contain a negative sign to signify whether the regulated bus is on the FROM or TO side of the transformer. Simulator does not need this because we always calculated a tap sensitivity when moving transformer taps. However, Simulator was not consistently managing this flag when reading from one format and then writing to a different format (e.g. load from RAW and then write to EPC). This has been fixed.
• (November 11, 2008) Cleaned up various errors with October 31 addition for renumbering and renaming dummy buses for multi-section lines.
• (November 11, 2008) Added checks throughout to make sure that for Switched Shunt records, the negative blocks come before the positive blocks. Simulator always considers negative blocks separately from positive, but when writing out blocks to RAW or EPC files the negative blocks must come first.
• (November 22, 2008) Fixed potential error related to sorting switched shunt blocks.
• (November 24, 2008) Fixed error in the automatic detection of the RAW file version when loading in RAW files. This would make some earlier versions of RAW files appear to be version 29 files.
• (November 24, 2008) Fixed error that occured when reading the area records of a RAW file if the area record did not incdlue an area name.
• (December 11, 2008) Fixed a bug that could cause the PWB file to become corrupted if it was saved with unlinked elements in an injection group.
• (December 22, 2008) Fixed error when reading EPC files if a tertiary bus was numbered zero (0). Checks for non-existent tertiary bus were expecting a negative number. This has been fixed.
• (January 8, 2009) When reading in EPC files, Simulator maintains extra GE data from the file. In the past this had included the transformer MVA Base, Voltage Bases, and Fixed Taps. These are now all stored with the Simulator data structures as well. When writing back out two-winding transformers to GE EPC files however, if the case had originally been read from an EPC file then Simulator was writing out the values that had been read with the GE Extra Data. If the values had not been edited this would not be noticed, but if changes were made in the transformer base values they would not be written out as changed.
• (February 3, 2009) For the GE EPC format, a problem was fixed with converting the min and max tap values when reading transformers with non-unity fixed taps on the FROM side of the transformer.
• (March 16, 2009) When writing out GE EPC files, current and power setpoints are calculated from the setpoints given to populate the EPC file.
• (May 1, 2009) When loading in an EPC file, when Simulator encountered any status values that were not appropriate no error message was generated and the device behaved incorrectly. This was first noticed with a case that had a branch status of -4. To correct this, and status which is not 0, 1, (or 2 for branches) will always be treated as closed and a log message will appear stating this.
• (August 10, 2009) Fixed an access violation that could occur when writing out a RAW file if the name of the limit group "Default" was changed.
• (August 10, 2009) Fixed an access violation that could occur when writing out a RAW file if a switched shunt that was modeling a FACTS device was out of service.

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Auxiliary Files (SCRIPT and DATA Sections)

• (October 5, 2007) Access to the multi-directional PTDF value results through the script commands such as SaveData was not working properly and blank values were returned. This has been fixed so it works in scripting.
• (October 11, 2007) Fixed bug introduced in October 5 patch with loading in branches and interfaces with custom fields greater than the number of currently defined custom fields.
• (October 11, 2007) Fixed bugs related to accesses AreaTieLine or ZoneTieLine object through the script commands.
• (December 12, 2007) Fixed a solution bug introduced in the December 5 patch that would occur if you read a power system case from an Auxiliary File.
• (December 19, 2007) Fixed the OpenOneline() script command so that in 3D when going to a view and toggling full screen, Simulator properly does the Toggle Full Screen FIRST and then the go to view.
• (January 4, 2008) When reading in interface elements using Name_NomkV values as secondary keys, the direction of the monitoring was not always being set correctly. This has been fixed.
• (January 4, 2008) Made sure that when using the command CloseOneline that the a prompt to save the oneline is not generated.
• (February 14, 2008) Fixed potential error if the syntax of an Auxiliary File was improperly terminated. Simulator will now gracefully fail when this occurs and notify you that the AUX file is bad.
• (March 26, 2008) Fixed WriteTextToFile() script action to replace two doublequotes with a one doublequote after extracting. Done to allow a doublequotes in the text written to a file.
• (March 26, 2008) Modified reading of script commands to properly error if you run across a doublequote " or left bracket [ immediately after reading in a string separated by doublequotes.
• (March 26, 2008) Corrected problem with flow arrows being drawn in the wrong direction if updating a line from an AXD file and loading in the points in the opposite direction from what they had been previously defined.
• (May 15, 2008) Removed a message log warning when reading in Advanced Filters which refered to another filter. The warning message was not valid.
• (June 5, 2008) Fixed error when saving a case as an Auxiliary file for transformers that had different Nom kV bases than the buses they were attached to. The impedances on the transformer base were being included in the AUX file when they should not have been.
• (June 23, 2008) When writing out unlinked interface elements to an AUX file, extra quotations were being added around the unlinked string. This was then causing an error when loading back in the AUX file. This has been fixed.
• (July 11, 2008) Transformer parameters were not being read in the correct order from auxiliary files resulting in phase shifter information not being read in the correct units. This would only occur if a phase shifter was currently not defined as a phase shifter and was being set to a phase shifter via the auxiliary file. The problem with the incorrect units has been fixed.
• (August 8, 2008) Fixed bug with allowing either comma or space delimiters in the SUBDATA section used to define points for background lines, transmission lines and other objects represent a graphical line.
• (September 8, 2008) Fixed problems setting the three winding transformer impedance parameters to new values in the string grid or from an aux file or script.
• (October 15, 2008) Apply filter when getting list of PV results through SaveData and SaveDataWithExtra script commands. Filtering was working on the dialog just not through scripting.
• (October 31, 2008) When loading branch records, error checking to prevent a branch whose from and to bus were the same has been added.
• (December 8, 2008) When saving complete oneline to a display auxiliary file (AXD), we now save the views at the end of the file so that if a contour is applied to the current view it will be applied properly.
• (July 2, 2009) Using the area/zone filtering option on the Auxiliary File Export Format Description was not working properly. This has been fixed.

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Simulator Automation Server (SimAuto)

• (November 15, 2007) The Message Log was becoming visible up when running a SimAuto process. This has been fixed so that the message log does not appear.
• (June 13, 2008) Fixed bug in ChangeParametersMultipleElementFlatInput that caused errors for Matlab users trying to use this function through SimAuto

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Case Information Displays

• (October 22, 2007) Fixed potential error that could cause under unusually situations that could cause program halt when showing header hints or hints for shown fields on the case information display.
• (November 13, 2007) When reading in an Advanced Filter from a version 12.0 or earlier PWB file, if the filter conditions applied to an integer field type (such as bus number), then the filter conditions was not being read properly. This has been fixed. The bug was related to a new feature in Simulator 13 in which we now store integer values as integers instead of floating point numbers. (fixed bug in older versions where 123456789 was treated as 123456790).
• (November 13, 2007) Fixed bug that would occur when Ctrl-Click was used on the Model Explorer to open a new Model Explorer.
• (November 13, 2007) On the Model Explorer, the options to "Save Selected Records or "Save Selected Records and Columns" was not working properly and was saving the entire case information display. This has been fixed.
• (November 13, 2007) Dynamic Formatting can be set to apply to case information displays. When using a lookup table associated with the Fill Color or Font Color however, this was not working properly. This has been fixed.
• (November 13, 2007) Fixed error that would occur when trying to paste data into PartPoint list on the Injection Group case information display. This error occurred because the "Contained By" column was not shown even though it's a key field.
• (December 19, 2007) When using the DC approximation and then showing the Area Losses and Interchange in a case information display, the value for losses was being calculated incorrectly (it should just be zero). The loss error resulted in the interchange being shown incorrect as well. Note that the actually solution algorithms were using the correct values internally, so this was only a user interface error.
• (February 24, 2008) Fixed problem where it was possible to set the transformer nominal winding voltages and transformer base MVA to 0 in the case info displays. Doing so could cause floating point errors when trying to access or use the values in calculations. Simulator will no longer allow setting the values to 0 in the case infos, and will also detect and change values already stored as 0 in a PWB.
• (February 24, 2008) Fixed the Limit Monitoring and Display Filter case information displays for Areas and Zones. Previously the customization of columns on these grids did not work completely correctly.
• (March 26, 2008) Removed extra sensitivity field from bus fields.
• (April 25, 2008) When reading in filters from a PWB file, BETWEEN filter conditions that operated on integer fields (such as a bus numbers) were not properly read from the PWB file. The second comparison value was always being read as a zero. This has been fixed.
• (April 25, 2008) Cleaned up errors related to new feature in previous patch for showing a filter drop-down menu if there were more than 10 filters.
• (April 25, 2008) Fixed potential error when applying a switched shunt Advanced Filter to the bus records.
• (May 15, 2008) Fixed some refresh errors on case information displays which would result in all the enterable colors appearing as black.
• (May 15, 2008) When choose the Options drop-down on the Case Information Toolbar, some strange access violations errors could occur if the size of the Simulator window was small. This has been fixed.
• (May 15, 2008) It was not possible to paste data into the Line Shunt Case Information Display because of conflicts between the column headings of Line Shunts and Branches. Changed the column headings on the Line Shunt object Status and ID columns so that they do not conflict with the Status and ID of the branch associated with the Line Shunt.
• (June 13, 2008) On the Injection Group Participation Point case information displays, the automatic recalculation of participation factors was occurring for participation points under some circumstances. This has been fixed.
• (June 13, 2008) An access violation could occur when using a substation filter on a Bus Case Information Display. This has been fixed.
• (September 8, 2008) Fixed problems setting the three winding transformer impedance parameters to new values in the string grid or from an aux file or script.
• (November 22, 2008) Fixed error that could occur when viewing the decoupled power flow matrices in Edit Mode.
• (November 22, 2008) When loading in an auxiliary file which includes DATAGRID customizations, if the data grid was not already customized in Simulator the values would not be read properly. This has been fixed.
• (February 3, 2009) The value for MW and Mvar losses shown on an Interface table were off by a factor of SBase. Thus for SBase=100, if losses were 1 MW, the interface showed 0.01 MW. This has been fixed.
• (February 18, 2009) Fixed parsing of the area slack bus number/name string.
• (April 9, 2009) The drop-down button on Case Information toolbar which shows a list of available filters was broken in the patch released yesterday. This has been fixed. This only effected that button and access to filters via right-click or the Filterbar was unaffected.

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User Interface Dialogs

• (October 5, 2007) When using multiple monitors and dragging the message log outside of the main Simulator Window, on some systems it was possible to cause other windows to a portion of the screen that isn't visible.
• (October 22, 2007) Fixed nuisance access violation when deleting a Data Block Description on the Auxiliary File Export Format Description dialog.
• (October 22, 2007) Changed default shunt impedances to zero for the zero-sequence data for a transmission line.
• (October 22, 2007) Fixed potential error on the Nomogram Dialog.
• (October 22, 2007) Fixed error with the Add New button on the Limit Group Dialog
• (November 15, 2007) Changed the injection group field for "Load MW Particiaption Factor" to consider all loads in the injection group. Previously it was only considering loads marked as AGCable which made the value inconsistent with the value shown on the injection group dialog.
• (November 21, 2007) On the Move Equipment dialog, the case information display showing the devices to move was not being refreshed properly when opening the dialog. This has been fixed.
• (December 7, 2007) When showing the list of advanced filters and then right-clicking and choosing Show Dialog, and error would occur if a filter was then deleted from the Advanced Filter Dialog.
• (December 19, 2007) More modifications to ensure that maximized windows to not appear as unmaximized even when they are maximized.
• (December 19, 2007) When inserting a generator in Edit Mode, an access violation was recently introduced. This has been fixed. The error was a nuisance and related to moving the stability models onto the dialog.
• (January 4, 2008) When opening the Area Dialog, the area slack bus number was not being set properly and this was causing the Area Slack bus to be removed from the Area. This has been fixed.
• (January 12, 2008) Fixed an error that occur whenever you tried to delete a Custom Field Description object.
• (January 12, 2008) When changing the color scheme of the Ribbon Settings, this choice is supposed to be saved in the Windows Registry so that the next time you open Simulator your color scheme is maintained. This as not occurring and this patch fixed this problem.
• (January 28, 2008) Fixed a problem with the case information displays not properly refreshing when you first open the DC Loss Load Multiplier dialog.
• (February 6, 2008) Fixed bug when displaying custom fields on object dialogs when the number of custom strings was not the same as the number of custom integers.
• (February 6, 2008) Fixed potential access violation when deleting three-winding transformers and then choose to NOT delete the two-winding equivalent branches that represent the three-winding transformer.
• (February 14, 2008) Fixed error that could occur when using the DC approximation and then trying to use an Injection Group to scale load or generation from the System Scaling Dialog.
• (March 12, 2008) Fixed access violations that would occur after using the shortest path calculation.
• (April 16, 2008) Fixed potential problem with the Edit Mode Switched Shunt dialog. After saving the switched shunt from this dialog, references to the switched shunt from injection group records or contingency elements could become unlinked.
• (April 16, 2008) When opening the area dialog, the assignment of the Super Area was not working correctly. This was causing the super area assignment to be removed. This has been fixed.
• (May 15, 2008) Fixed potential access violation that could occur when in Floating Windows mode and opening the Dynamic Formatting dialog.
• (July 11, 2008) Allow reactive capability curve point at 0 MW with both the Mvar minimum and maximum at this point set to 0. This was allowed if data was loaded in from an auxiliary file but it wasn’t permitted when making changes to the reactive capability curve from the generator dialog. This has been fixed.
• (September 26, 2008) When showing the reactive capability curves, the Y axis min/max values were being calculated based on the Min/Max Mvar output at 0.0 MW. For normal capability curves this was fine, but if the user made the Min/Max Mvar output very small at this point the curve was not drawn correctly.
• (October 31, 2008) When clicking to delete the First tab in the Model Explorer it would always remove the first entry in the Recent folder instead of the one being displayed. This has been fixed.
• (November 22, 2008) Fixed errors on the Three-Winding Transformer dialogs when specifying three-winding transformer parameters and then choosing to build the two-winding equivalents. This bug was related to the enhancements made in June to synchronize the three-winding and two-winding equivalent models.
• (December 8, 2008) Fixed error on the Three-Winding Transformer Dialog. When changing three winding XF nominal voltages or taps on this dialog, those values were not correctly saved and were not correctly reflected in the equivalent two winding XFs when creating the two winding equivalent transformers.
• (February 18, 2009) Fixed potential errors in displaying the bus numbers in a drop-down box when bus numbers had more than 5 digits.
• (February 18, 2009) The equations which were displayed on the dialog for specifying transformer taps and impedances on the transformer base were incorrect. This image has been corrected.
• (April 8, 2009) Modified the equations on the dialog for specifying transformer impedances on the transformer base. The shunt terms are not effected by the fixed taps or nominal kV values.
• (April 28, 2009) Modifed the scaling of loads to ensure that generators do not also scale if the generator scaling is set to 1.000. Previously if you were enforcing generator MW limits in the scaling, Simulator would automatically bring generator up/down to their limits and then scale other generators appropriately so the net generation change was zero.
• (August 10, 2009) When using the Move Equipment Dialog, the ID of switched shunts was not being maintained if the shunt was moved to a bus that already had shunts at it. This has been fixed so that as long as the ID remains unique it is maintained.

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Oneline Diagrams

• (October 5, 2007) The 3D Stacks for generator objects were not being drawing with the proper width. This has been fixed.
• (October 22, 2007) Modified interaction with the Geo Data Views when creating a new oneline diagram on which to draw the Geo Data View.
• (October 22, 2007) Fixed potential access violation when using a lookup table the Dynamic Formatting feature.
• (October 22, 2007) Fixed bug in which dc lines were not displaying correct MW flow when option MW & Mvar option was chosen.
• (October 22, 2007) Fixed access violation when right-clicking on an unlinked transmission line display object.
• (November 13, 2007) When using the Bus or Substation palette, by default lines, generators, loads, and shunts are auto-inserted as buses/substations are added to the oneline. There was a bug that fields were not being properly inserted automatically until AFTER the Auto Insert Options was opened. This has been fixed.
• (November 13, 2007) Fixed bug in copying and pasting records and objects from one case to another. The loads, gens, lines and some fields were not being properly pasted.
• (November 13, 2007) The Recalculate Contour button of the Contouring Menu on the Onelines Ribbon Tab was not working properly. This has been fixed.
• (November 15, 2007) Simulator does not support copying and pasting data records from one case to another by graphically selecting DC lines, Interfaces, or MS lines. Fixed a bug to avoid access violations when trying to do that.
• (December 7, 2007) Fixed an error that was caused when opening a oneline diagram using "Name_kV linking". The error causing diagrams to not link when opening this way and caused access violations.
• (December 12, 2007) Fixed a bug that was causing the generator, load, and switched shunt oneline objects to not draw their circuit breakers
• (December 19, 2007) Fixed the Short-Cut key method so that on a 3D oneline when choosing to both go to a view and Toggle Full Screen, Simulator properly does the Toggle Full Screen FIRST and then the go to view.
• (December 19, 2007) Fixed issues with Font Width and Height being properly sized in 3D onelines.
• (December 19, 2007) Modifed 3D onelines so that layers that are now being shown to not show their elements when in 3D.
• (January 4, 2008) When in Run Mode, if any field which had a background fill color its text was presently blank would appear as a small square with the fill color. This has been changed so that if the text is blank, then nothing is drawn to the screen.
• (January 4, 2008) Fixed bug in text object. When no text, it won't be displayed in run mode.
• (January 4, 2008) The Oneline object Format Dialog was not working to change fields to show values represented by the Custom Field Descriptions.
• (January 28, 2008) Fixed the Display Auxiliary Files (AXD) so that they can be opened in Run Mode.
• (February 6, 2008) Fixed problems with switching to 3D mode in an embedded oneline when using keyboard shortcuts.
• (February 6, 2008) Fixed omission where circuit breakers didn't display their orientation or style in the case info or AXD file.
• (February 14, 2008) Fixed errors when loading in an older PWD file with Interface objects on a oneline diagram. The error resulted in flows arrows appear backwards on the interface object.
• (February 14, 2008) If a keyboard shortcut is executed to open a oneline embedded within the currently active oneline and a oneline isn't currently active, now Simulator will chose to embed in the last active oneline.
• (February 24, 2008) If a transmission line was showing MVar flows flow out both ends or flowing into the line at both ends, then the flow arrow option for Minimum Pixel Size for flow arrows was being ignored on flow arrows in the middle of these lines. This has been fixed.
• (March 12, 2008) When linking multi-section line display objects, set the number of sections equal to the linked object. This will prevent access violations if a display file is loaded with a different case in which the same multi-section line contains a different number of sections.
• (March 12, 2008) Fixed bug that wasn't displaying the dynamic formatting correctly when using emphasis highlighting.
• (April 16, 2008) Removed the showing of oneline hints on unlinked elements.
• (June 5, 2008) Fixed an error with defining a memo with a Screen Layer that corrupted PWD files. This feature was only available from the Screen Layer Dialog and will be removed for Version 13. It will be included in future versions of Simulator.
• (June 13, 2008) Fixed access violation when loading in an AXD file and the orientation of a circuit breaker was blank.
• (June 13, 2008) When opening a oneline diagram using "name/kv linking", if the name/kv of the device could not be found in the case, Simulator would keep the bus number read from the PWD file. This has been changed so that if the name/kv bus is not found, then the device is properly unlinked.
• (June 23, 2008) Increased the speed of renumbering buses on a oneline diagram
• (June 27, 2008) Fixed error with reading in a DBF file as part of a shapefile/dbf file pair if the DBF file had date fields in it denoted by the "D" in the DBF file.
• (July 18, 2008) Fixed unusually slow auto-insertion When auto-inserting buses if there were more than one thousand buses at the same x/y or longitude/latitude coordinate.
• (September 26, 2008) Fixed bug in which the memos in oneline diagrams were causing an access violation when being inserted. This only occurred in Vista systems.
• (September 26, 2008) Corrected bug when loading in AXD file using secondary key fields if a transmission line has parallel circuits the circuit number wasn't being read so multiple lines were not being created.
• (October 31, 2008) Fixed potential access violation that could occur when removing too many vertices from a line.
• (November 11, 2008) Dramatically increased the speed of the option "Add Fields around Selection" When selecting a 1000s of objects.
• (November 11, 2008) When showing a oneline using full screen, it was sometimes possible for the main PowerWorld window with the Ribbon and menus to appear on TOP of the full screen oneline. This has been fixed so that full screen onelines always force themselves to the top.
• (November 22, 2008) Fixed an access violation that could occur when deleting a background object which belonged to a group.
• (November 22, 2008) When opening a oneline diagram using the AXD file format in RUN mode, the oneline would be opened as editable. This has been fixed. Editing should only be allowed in run mode on the oneline.
• (December 8, 2008) If a line flow object was anchored to a line object and the from and to bus were not drawn on the oneline diagram, then the "auto-determine angle when anchored" feature of the line flow object was incorrectly flipping the arrows 180 degrees. This has been fixed.
• (December 8, 2008) Fixed access violation errors that occurred when merging buses more than once on a oneline diagram.
• (December 22, 2008) Fixed one more access violation errors that occurred when merging buses more than once on a oneline diagram.
• (February 3, 2009) When reading contour setup information from an AXD file, the advanced filter referenced by a contour was not being properly read in. This has been fixed.
• (February 3, 2009) Fixed access violation that would occur if terminately the drawing of a line by hitting the ENTER key instead of hitting DblClick.
• (March 16, 2009) When right-clicking on an area field and choosing to show the Area Information Dialog, the dialog was not being shown. This has been fixed.
• (April 14, 2009) When adding an interface field to a oneline diagram on which no interface display objects are drawn a nuisance access violation would occur. This has been fixed.

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Bus View and Substation View Onelines

• (November 21, 2007) Fixed problem with circuit breaker sizing on the BusView. Previously they were too large.
• (December 5, 2007) Fixed problems with onelines opening as maximized yet not spreading themselves across the entire window.
• (December 5, 2007) Fixed bug that occurred when a bus view was reduced to height zero. This caused divide by zero errors.

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Power Flow Solution

• (October 5, 2007) Added checks throughout to prevent the two-terminal and multi-terminal DC line converters from having their tap ratios set to zero. This should not be allowed and is no longer allowed.
• (October 5, 2007) In Simulator 13, the ability of the area interchange control to handle areas that span multiple islands has been greatly improved. A bug was introduced for Super Areas that span multiple islands which has now been fixed.
• (December 12, 2007) Fixed a solution bug introduced in the December 5 patch that would occur if you read a power system case from an Auxiliary File.
• (December 19, 2007) Fixed solution error in the Decoupled Power Flow that could occur for remotely regulated buses. Would result in power flow divergence.
• (January 28, 2008) Fixed bug that would occur when equivalencing a bus that had NO generation, NO load, and NO shunt connected, and was also connect to the system by a single branch with had a non-zero phase shift.
• (March 12, 2008) Fixed initialization of MW Control solution after loading a RAW or EPC file. Some changes made to the reference state in the February 14 patch might cause a problem when first trying to solve the case.
• (April 16, 2008) When using the solution option to Disable Generator Mvar Limit Checking, Simulator was also not checking the Mvar limit of CONTINUOUS switched shunts that were being treated as PV buses.  This has been fixed.
• (April 25, 2008) Fixed potential errors that could occur in the fast decoupled power flow as generators hit their minimum/maximum generator Mvar limits.
• (June 13, 2008) When closing in a line directly adjacent to a two-terminal DC transmission line, and then solving the case, an access violation would occur. This has been fixed.
• (June 23, 2008) When using the DC approximation, if area tielines spanned two multi-terminal DC buses, the ACE calculation was performed incorrectly. This has been fixed.
• (June 23, 2008) Fixed a bug in parallel transformer tap balancing that occurred only for very unusual tap settings. If two parallel transformers had different step sizes with one being exactly 1/2 of the other, then tap balancing could cause osciallating taps.
• (July 11, 2008) Previously when the sum of Unspecified MW Interchanges do not sum to zero, Simulator will set the AGC Status to "Off AGC" for the area (or super area) to which an island slack bus belongs.  This has now been modified to only happen if the island involved includes multiple areas (or super areas).
• (September 26, 2008) When using PostCTG for the Line Drop Compensation, if a generator was operating at an extremely low per unit voltage (say < 0.3), then it was possible for the line drop to be impossible to implement. Error checking is done to prevent this generally, but was not being done for the PostCTG situation. This has been fixed.
• (October 31, 2008) Simulator would not allow transactions between areas that did not belong to islands which were directly connected. This has been modified to properly allow transactions that traverse multiple islands.
• (January 14, 2009) January 13 patch was causing the Post Power Flow Solution Actions to be skipped.  This has been fixed.
• (April 28, 2009) Fixed more minor errors related to ensuring that transformer taps do not get stuck at their limits.
• (May 1, 2009)When all DC converters in a multi-terminal DC line had power or current setpoints of zero, Simulator would generate a log message saying there were no rectifiers or inverters found. The solution was fine but the log message was confusing and has been removed.

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Sensitivity Calculations

• (July 2, 2008) Starting with the June 23 patch, the PTDF dialog was not opening giving an error regarding "dxBarSubItemFilterBar". This has been fixed.

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Contingency Analysis Tool

• (November 13, 2007) Removed the "Set Options" and "Reset" button on the Options Tab of the Contingency Analysis Dialog. These buttons did not actually perform any function any more.
• (November 13, 2007) Modified so that when opening the Contingency Analysis form the list of contingencies is activated immediately so that the Case Information Toolbar acts on this case info by default.
• (December 5, 2007) When using filters to auto-insert BUS and GEN outage contingencies, the filters were not being properly applied. This has been fixed.
• (January 4, 2008) Fixed a bug introduced during optimizations made on December 12. This would result in erroneous results if you chose "Solve Selected Contingency" and then immediately choose "Solve Selected Contingency" on the SAME contingency again.
• (January 12, 2008) Fixed error when writing out the old contingency text report and including the database friendly files. Problems could occur for Contingency elements involving gens, loads, and shunts that used the Move, Set, and Change By actions.
• (February 14, 2008) Fixed potential bug when restoring the contingency reference state that might occur if a previous contingency modified the island records of the contingency. Bug could cause solution difficulties when a subsequent contingency involved a large generation or load outage.
• (February 15, 2008) Fixed silly bug in February 14 patch regarding the Post-Contingency AUX file.
• (March 12, 2008) Fixed the handling of the combination of two contingency actions that acted on the same generator, load, or switched shunt. Specifying to close generator X, and then set its output to a value was not always working properly.
• (March 26, 2008) Fixed bug that would create a new contingency when renaming contingencies on the Contingency Definition dialog.
• (March 26, 2008) Fixed error when using DC solution and approximating VAR flows assuming constant voltage.
• (April 25, 2008) Fixed bug writing out PTI *.con contingency file. An extra quotation mark was being written sometimes.
• (May 15, 2008) There was a minor bug when defining a custom expression on the Contingency Violation List off the Combined Tables> dropdown. If you choose to have Simulator automatically add the column after defining the expression, the column was not correctly added.
• (June 27, 2008) Fixed bug created by enhancement made on June 13 related to detecting islanding in the linearized contingency methods. This bug could cause slow solutions or errors in the SCOPF and ATC as well.
• (June 30, 2008) Completed bug fix created by enhancement made on June 13 related to detecting islanding in the linearized contingency methods. This bug could cause slow solutions or errors in the SCOPF and ATC as well.
• (August 18, 2008) When loading in ATC results from an auxiliary file, there was a bug that would create duplicate contingencies with no elements. This has been fixed.
• (March 23, 2009) When using the DC approximation (the DC Power Flow) with contingency analysis, the advanced contingency monitoring options were not being used. They are now included.
• (April 8, 2009) Fixed errors with modeling Bus Outages which create islanded load and generation using the Linearized Contingency Analysis methods.
• (April 28, 2009) Fixed nuisance access violation that occured on the Lines/Buses/Tranformers tab of the contingency analysis form when toggling the Selected or Skip field on the list of related contingency violations for each branch, interface or bus.
• (May 6, 2009) When showing the "Present Value" for Interface MW Violations in contingency analysis, the values were displayed in per unit. This has been changed so values are displayed in MW instead.

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Time Step Simulation

• (May 22, 2008) Corrections so that Schedules with Time Step Simulation can properly be saved and loaded from auxiliary files.
• (May 22, 2008) Changed TSB file format to save zone load information. This required the addition of a new TSB file version option called "from May 19, 2008 version 13 build or earlier". This version will not contain the zone load information that would cause errors if the file was read in a version earlier than the current patch.
• (May 22, 2008) Fixed access violation when loading in a time step custom results file that contains elements that are not in the current power flow case.
• (June 23, 2008) Fixed problem reading in international Data/Time values for schedule subscriptions from an Auxiliary File.
• (July 2, 2008) Corrected a bug that was setting the TSS TimeScale to 60 when the case opened a TSB file automatically.
• (October 31, 2008) When loading in a list of Schedule Subscriptions, if the object did not exist in the case a dialog would appear. This dialog would appear for EVERY object that did not exist. This has been fixed so that messages are written to the log instead.

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PV and QV Curve (PVQV) Tool

• (November 13, 2007) The Injection Group columns for tracking data in the PV and QV Curve tool were not appearing as toggleable (green). This has been fixed.
• (November 13, 2007) Fixed bug that would not report the correct transfer level limitation when using the option to stop when voltages become inadequate.
• (December 19, 2007) Fixed a bug in the PV curve tool that could occur when ramping if the source or sink contained the island slack bus.
• (January 12, 2008) Fixed access violation that would result when writing out the QV tracking results to file and there were no newly crictical scenarios. The error produced in the QV curve didn't make it clear this was the error, but it is now fixed.
• (March 12, 2008) Properly set the minimum pu volt for constant power and current loads to 0 when doing the PV analysis. This had previously been done, but the option was getting set back to the original values between scenarios.
• (March 12, 2008) Corrected variablename descriptions and types for fields associated with injection group ZIP factors and Q multiplier for power factor.
• (April 16, 2008) When using scripts or SimAuto to obtain the PV curve fields for "Worst Voltage Violation", the values were always being rounded to an integer. This has been fixed.
• (April 16, 2008) Fixed bug that was causing the script action PVWriteResultsAndOptions() to not function properly.
• (May 15, 2008) Removed error message that would always be produced when saving out PV options from the dialog even when there was no error.
• (June 5, 2008) Fixed errors when loading in PV results from an auxiliary file because the "PVStudyName" was not being read correctly.
• (June 5, 2008) Fixed access violation that could occur when reading in a PV results AUX file that contained tracking for objects that could not be found in the power system case.
• (July 11, 2008) Correct system state was not being restored when output from the synchronous condenser was required to get an initial contingency solution. This could result in missing and/or incorrect results.
• (July 11, 2008) QV results could not be filtered by creating an advanced filter. This has been fixed.
• (July 18, 2008) During the QV curve analysis if switched shunts that are on control exist at the curve bus, an attempt is made to have var support provided by the shunts in addition to the fake synchronous generator that is added at the bus to trace the curve. Sometimes during the process of determining how much support should be provided by the switched shunts, a seemingly infinite loop of power flow solutions could be entered. This could especially be a problem with continuous switched shunts. This has been fixed.
• (July 18, 2008) During the PV analysis, the power flow solution options for Minimum pu Voltage for Constant Power and Constant Current Loads are set to 0. The solvability of the base case with the 0 setting for these options wasn’t properly being tested before going into the remainder of the analysis. This is now done properly and a message, “Base case could not be solved with special PV solution options”, will indicate that the process cannot continue because the base case cannot be solved with these options.
• (August 18, 2008) Fixed bug when using merit order dispatch which caused difficulty when ramping out the transfer.
• (November 11, 2008) Fixed interaction on the PV dialog that was causing user changes to the Identify Inadequate Voltage checkbox to not register properly.
• (November 11, 2008) When choosing on the PV dialog to use a constant power factor without applying a Q multiplier, Simulator was not correctly forcing a Q multiplier of 1.0. This has been fixed.
• (December 11, 2008) Fixed bug that could cause inconsistent results when using merit order dispatch.
• (December 22, 2008) Fixed bug that could occur if the terminal bus of the first participation point in an injection group was disconnected from the system. This would result in the loss assignment during the PV ramping to show up on the system slack bus instead of being spread out amount the buyer.

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Available Transfer Capability (ATC) Tool

• (January 28, 2008) Fixed an error that could occur under specific situations when using the ATC Solution method "(IL) then Full CTG Solution". If the Full Contingency solution repeatedly failed the result wasn't being reflected correctly.
• (April 16, 2008) For the ATC EXtra Monitors, if the Relative Monitor Sensitivity Constant is set to zero, the ATC Extra Monitor sensitivity check is no longer done.
• (May 22, 2008) When doing linearized DC contingency analysis that includes injection groups with Set To or Change By actions and doing merit order dispatch, the MW output value of associated generators was being inadvertently changed resulting in errors. This has been fixed.
• (May 22, 2008) After loading in settings from an auxiliary file, the multiple scenario grids were not being refreshed to reflect the new data. This has been fixed.
• (June 13, 2008) When loading in ATC results for multiple scenarios, if a limiting element did not exist and access violation would occur. This has been fixed and an appropriate message is sent to the log if element is missing from the case.
• (September 8, 2008) Made correction to adding transfer limiters when both the max. number of elements and CTGs have been met.
• (February 18, 2009) Fixed access violation that could occur when viewing multiple scenarios results in the ATC dialog and then closing the dialog.
• (April 28, 2009) When using the iterated steps in ATC and ramping of the base case state, if the power flow fails the step size is reduced by a factor of 2. After a successful solution the entire remaining desired step was attempted immediately. This has been changed so that the decreased step size is used instead until the desired step is achieve or the minimum step size is reached. This should speed up the ramping in bad situations.

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Optimal Power Flow (OPF)

• None.

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Security Constrained OPF (SCOPF) Tool

• (November 15, 2007) Fixed a potential bug that occurs when setting the SCOPF Basecase Solution Method to the Optimal Power Flow. If you were also using fast start generators this could cause errors in the SCOPF solution causing it to terminate at an invalid solution.
• (December 5, 2007) Added the storage of several SCOPF solution options in the PWB format which previously were not in the PWB file. This included the SCOPF Base Case Solution Method.

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OPF Reserves

• (September 26, 2008) Fixed a couple of bugs in OPFR related to controls for regulation reserve down in zone constraints.

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Fault Analysis

• (November 22, 2008) When performing an in-line fault, the oneline diagram is automatically updated to reflect the new bus added. An access violation occured if the transmission line was on the oneline diagram but the terminal buses were not drawn. This has been fixed.

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Memory

• (February 3, 2009) Fixed a potential problem with accessing owner summary information if changes were made while in Edit Mode and Run Mode was never entered.
• (March 16, 2009) When deleting a multi-terminal DC line record (whether manually, through a script, or through equivalencing), a memory access violation was occurring which corrupted the case. This has been fixed.
• (June 18, 2009) Fixed a rare access violation that sometimes occurs when opening or closing a case.

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