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What's in the Simulator 10.0 Patch?

PowerWorld Simulator 10.0 Patch addresses any problems which are found in Simulator 10.0 after the official release of it in March 2004. New features are also added in the patch as appropriate. All fixes and new features are listed below.

The patch was last modified June 28, 2005.

Updates made to this patch are noted below along with a date and explanation. This patch was first introduced on March 16, 2004.

If you are ready to download this patch, click here to go to the patch download page.

New Features/Minor Improvements:

Case Information Displays

(March 23, 2004) When editing a cell in a case information display, if you closed the dialog before removing focus from the cell (by hitting enter or moving to another cell), then the value would not be registered. This has been fixed

(April 20, 2004) Added fields for Lines, Loads, Generators and Switched Shunts for displaying terminal bus island numbers

(April 20, 2004) Added a field for showing the power factor for an area

(April 20, 2004) Added field for showing the regulated bus number of the transformer MVar control options

(April 20, 2004) Added columns for showing the owner/area/zone numbers/names in the contingency definition list. If the contingency contains multiple owner/area/zones in the elements which it consists of, then they are listed with commas separating them.

(April 20, 2004) Added option right-mouse button local menu option on the interfaces case information displays for automatically creating reverse-direction interfaces from the selected interfaces.

(May 18, 2004) Modified the storage and setting of the "metered end" of a transmission branch. Previously when looking at this value in a case information display it would only appear for area-to-area tie-lines. This has been changed so that the value will always appear, but it will be shown as grayed out unless it is either an area or zone tie-line.

(June 1, 2004) For multi-section lines, the column MSLineName was made available. Previously you could not change the multi-section Line "name" via an AUX file or a case information display.

(June 21, 2004) Added new column for SuperArea for the MW Marginal Cost (weighted by Load)

(July 8, 2004) Enhanced the display of the Interface case information display so that it shows information about which elements are in each interface, as well as giving the user the ability to see a list of lines and which interfaces each line belongs to.

(July 8, 2004) Added support for reading/writing the "baseload flag" from GE EPC files.

(July 8, 2004) Modified so that the Limit Set case information display is properly refreshed when loading in new data from an AUX file from this dialog. Previously it would not show the new limit sets until you choose to refresh the list (or closed it and opened it.)

(July 26, 2004) Enhanced the injection group dialog so that it shows a list of participation points with the selected injection group.

(July 26, 2004) Modified so that the user may edit the metered end of a DC line and a multi-terminal DC transmission line. Previously these values were read from text files and were properly utilized, but there was no way to change them in Simulator.

(August 31, 2004) Greatly enhanced the performance of Simulator's sorting, filtering, and contouring routines when values columns being processed contained a mixture of numbers and strings. An example would be Bus MW Marginal Cost which shows the string "Not Valid" for buses in areas not being run on OPF.

(September 29, 2004) Added the ability to use Ctrl-Home and Ctrl-End to move to the start and end of a case information display.

(October 12, 2004) Two new case information displays have been added which show a list of all area-area tie-lines and all zone-zone tie-lines in an entire case.

(October 15, 2004) Modified to allow the specification of a blank longname for a Bus.

(March 7, 2005) Modified the columns for Area and Super Area "AGC Status" and "ACE" so that they appear as disabled when the user has set the case on island-based AGC control.

(March 17, 2005) Added the ability to pass a blank to a cell of a custom case info row to signify that it should be cleared. This allows you to clear a cell using an aux file or SimAuto command.

File Formats

(July 26, 2004) Added the ability to read in PROMOD Event files to define a list of interfaces (normally they have contingent interfaces).

(October 12, 2004) When reading PTI RAW files, no character limit is enforced for bus names now. Simulator can support longer bus names, so if the RAW file contains a longer bus name it is not truncated anymore.

(January 28, 2005) Added the storage of the Switched Shunt continuous element min/max susceptance blocks as separate blocks when writing out to PTI files. Also write discrete shunts with these continuous blocks out as continuous shunts to PTI.

(January 28, 2005) Changed some default values for solution parameters written to GE EPC files.

(January 28, 2005) Added the storage of the ConvergeTol, MaxIterations, and Gen MVar Check Immediately flag to the PWB file.

(April 19, 2005) Added support for skipping comment lines in PTI draw (*.drw) oneline files.

Auxiliary Files (SCRIPT and DATA Sections)

(April 2, 2004) Modified the reading of DATA sections in the auxiliary file format so that the strings "AUXCSV", "CSVAUX", and "CSV" will all signify that the data section using commas as separators. Previous help documents were not clear regarding what to use, so we now support all this strings to signify commas

(April 20, 2004) Added support for the more advanced MWStudyTransactions in the Simulator 10.0 AUX file.

(April 20, 2004) Added new script command for the auto-insertion of injection groups.

(May 3, 2004) Added new option on case information displays to "Save As, Auxiliary File (only selected records/columns)". Previously when choose to save "only selected", all columns would always be saved.

(May 3, 2004) Added columns for the sum of maximum generator MW outputs at buses. Also added fields for the sum of maximum/minimum Var outputs at a bus.

(May 3, 2004) Added ability to save OPF Solution Summary information to an auxiliary file. This may be done by clicking a button on the LP OPF Options Dialog or by calling a script command.

(May 3, 2004) Added new script command for solving a single outer loop of the OPF: SolveSinglePrimalLPOuterLoop.

(July 8, 2004) Added new script command SetSensitivitiesAtOutOfServiceToClosest for performing the button click seen on many sensitivity dialogs.

(August 31, 2004) Added support for the Selected field for Filter objects. This was added to allow the use of script commands for deleting a particular filter.

(September 29, 2004) Added ability to read/write the option regarding assuming constant voltage to adjust branch limits in the DC power flow via the aux file.

(November 16, 2004) When tapping a transmission line that was presently not part of a multi-section transmission line, and also specifying that the two new lines created should be treated as a multi-section transmission line, the newly created multi-section line would not work properly. This was true whether the line was defined from a script command or via the user-interface. This has been fixed.

(November 16, 2004) Modified the script commands SolvePrimalLP, SolveFullSCOPF, and SolvePowerFlow so that you can pass in parameters showing blank filenames. These filenames will then be ignored. Previously the script would not execute if the file specified did not exist, even if the file name was blank.

(January 13, 2005) Modified the list of all area transactions so that you can paste into the display from the clipboard.

(February 23, 2005) Modified the Limit Group so that the toggling and setting of whether the higher or lower end of a branch is considered the limiting end.

SimAuto

(October 15, 2004) Added a new call called ListOfDevicesAsVariantStrings which returns all values as variant string instead of strongly typed integers, strings, etc...

(November 4, 2004) Modified SimAuto commands so that those which pass in a filtername will recognize the special names AREAZONE and SELECTED. When AREAZONE is passed then only objects meeting the area/zone/owner filters are used. When SELECTED is passed then only object whose Selected field is set to YES are used.

(November 24, 2004) Added two new SimAuto function called ListofDevicesFlatOutput and GetParametersMultipleElementFlatOutput. The output of these methods is similiar to the calls without the "flatoutput", however they return an extra parameter specifying the number of fields returned for each object, and also return the resulting information as a large vector instead of as a multi-dimensional array. This was added to support languages that do not support multi-dimensional arrays.

(February 11, 2005) Added a new function in SimAuto to return the build date of the Simulator program as an integer value.

(March 14, 2005) Modified the SimAuto calls which take primary keys so that they can also use the secondary keys such as Name_kV. Previously the SIMAUTO calls only worked when using the primary keys.

Power Flow Solution

(April 20, 2004) Added support for treating Switched Shunts that are on Continuous control as "PV" buses (this includes remote bus voltage regulation as well). This results in continuous shunt voltage control occuring in tandem with generator voltage control inside the inner power flow loop. Previously all shunt control occured in a voltage control loop outside of the inner power flow loop. Discrete shunt control still occurs in the voltage control loop.

(May 21, 2004) Added support for handling a situation when all the generators that are controlling a remote regulation bus's voltage have remote reg percentages of zero. When this occurs, the Vars are split equally among the generators now. Previously this would cause the Vars to never move.

(May 21, 2004) Modified so that the when inserting new transmission lines, the lines are marked as having just changed their status. This allows the angle smoothing routine to be utilized when performing a solution immediately after inserting a new transmission line.

(November 16, 2004) The calculation of the generator slack bus output would be improperly performed if the area containing the slack bus was on participation factor, and other areas were not on participation factor control. The power flow was using the correct power output, but the displayed value seen in the user-interface was incorrect.

(April 7, 2004) At the beginning of the power flow solution, all transformers that have tap or phase settings outside of the max/min tap/phase are now brought back inside their range.

Contingency Analysis

(May 3, 2004) Modified the Combined Tables in Contingency analysis so that it also included columns for Contingency Owner, Area, and Zone when they are shown in the Contingency Violation and Contingency Definition Tables.

(May 3, 2004) After reading an auxiliary file, unlinked interface elements (and injection group participation points) were previously ignored. They are now stored temporarily and display on the interface element dialog (and Particpation Point Dialog) as "unlinked". These unlinked elements are not stored in the PWB file however. They are only maintained for AUX file support while that case is open.

(May 18, 2004) Modified the use of Model Criteria used in conjunction with contingency blocks. Previously if a model criteria were specified for the contingency block, then this model criteria would override the model criteria specified for the individual actions inside the block. Simulator will now perform an AND if a model criteria is specified at bother contingency block level and the individual actions inside the block.

(August 31, 2004) Added option in contingency analysis for skipping the post-power flow solution actions.

(August 31, 2004) Added a new SUBDATA section "CTGElementAppend" to the objecttypes Contingency, CTGElementBlock, GlobalContingencyActions, and PostPowerFlowActions. Actions specified inside these sections will be appended to a definition instead of replacing the actions presently specified.

(May 18, 2005) When using the linearized lossless DC methods for performing contingency analysis, the advanced limit monitoring option for suppressing base case violations was not working properly. This has been fixed.

PV and QV Curve Tool

(July 8, 2004) Modified to allow the tracking of transformer control and switched shunt control quantities.

(July 26, 2004) Added the ability to ramp injection groups by "merit order" instead of all of them together. When this is done, generators will ramp to their limits in order according to the participation factor. Generators with larger participation factor will ramp first. (August 10, 2004) Fixed error which occurred with "merit order" dispatch when all the generators hit their limits.

(August 31, 2004) Added new save options when saving settings and results on the PV and QV curve dialogs. It now will prompt you regarding whether to save information such as contingency analysis settings, solution options, etc... related to these tools.

(September 7, 2004) Added the ability to signify with the PV Results which contingency scenarios became critical at which base case transfer levels. (Sept. 10) Fixed new feature to ensure that a comma is added before the critical contingency name when saved to a CSV file.

ATC Tool

(February 4, 2005) Increased the maximum number of scenarios for each object type from 50 to 128.

(March 16, 2005) Previous change increased max scenarios to 128, but the buttons that set the number of scenarios were not letting it be set higher than 50. The buttons have now been fixed.

(June 15, 2005) When using injection groups in conjunction with the iterated ATC solution methods, the method for ramping the transfer could sometimes result in not achieving the correct amount of transfer. This was related to the slack bus picking up part of the losses when Simulator is designed to assign all losses to the buyer injection group.

Oneline Diagrams

(March 16, 2004) You may now specify keyboard shortcuts for the F1..F12 function keys along with combinations of Shift and Ctrl with the function keys. These shortcuts can be configured to open a specified oneline diagram and move this diagram to the a specified Saved View.

(March 16, 2004) Added many more options regarding how a substation object is drawn on a oneline diagram. This allows you to customize the location and size of symbols representing generation, load, shunts, number of buses, as well as to add two extra substation-based fields to the object. Also you may specify whether to shrink text or truncate text when it does not fit on the object. (See oneline display options on a oneline with substations)

(March 16, 2004) Right-clicking on an interface field will now give you the option to open the field dialog or the interface object dialog.

(April 2, 2004) Added support for the F13..F24 function keys as short cut keys.

(April 2, 2004) Added the ability to using the format of multiple objects to change the rotation angle of text and field objects.

(April 20, 2004) Added option for Oneline Option, Pie Chart Options for specifying a minimum font size for pie charts which are above the warning percentage. This will cause pies above the warning value to scale up to a size at least large enough to result in a font of the specified size.

(May 3, 2004) Enhanced the Substation oneline display objects so that field may be shown to the left or right of the substation name as well as above and below.

(May 3, 2004) Added option to hide unlinked objects on oneline diagrams when you're in Run Mode

(July 26, 2004) Added new option in contouring regarding whether to utilize the "Fade To Value". The default will be false from now on.

(August 10, 2004) Added ability to insert multiple color points on a color map with a single right-click action.

(August 31, 2004) Added the ability to contour by different ranges of values instead of specified values. This includes contouring by percentile, dynamic range, and a range specified by the number of standard deviations away from the mean.

(October 22, 2004) Added the ability to use a Custom Model Expression inside of a Model Condition or a Model Field. This enables you to show the result of a Custom Model Expression on a oneline diagram using the Generic Model Field.

(November 24, 2004) Modified the creation of new transmission lines so that the color of the initial line is white for background that are a dark color. Previously new lines were always black while they were being drawn. This made drawing a line on a black background difficult.
(November 24, 2004) When choosing to make pie charts the same color as the line to which they were anchored, the warning and limit coloring was not permitted. This has been changed so that the anchored color is only used as the normal color, while the warning and limit colors are still used.

(January 13, 2005) Added a new toolbar button labeled "Toggle Full Screen" which will toggle the presently active oneline so that it displays in full screen.

(May 10, 2005) Modified the oneline links so that they may also automatically open AUX files.

Bus View Oneline

(March 16, 2004) This is a new option under the Option> to specify whether to "Show Field Suffixes". If you uncheck this option, then the units which appear on most fields will be removed. Using this in conjunction with the "Include Field Labels" option is encouraged.

User Interface Dialog Modifications

(March 23, 2004) When modifying the percentage and per unit voltage values on the Limit Monitoring Settings/Violations dialog, if you closed the dialog before removing focus from the edit box, then the value would not be registered. This has been fixed.

(April 20, 2004) Added a string grid to multiple TLR display for showing TLRs at generator buses only.

(April 20, 2004) Added toolbar button for removing a contour.

(July 26, 2004) Modified so that you can click on the Area Gen IC Graph and query which generator that graph belongs to.

(July 26, 2004) Added a memo tab to the Bus Dialogs so that the memo can be easily viewed and edited.

(July 30, 2004) Added a new option on the select by criteria dialog to select only visible objects.

(August 10, 2004) Modified the Scaling Dialog so that it had a smaller height and was better able to fit on the screen.

(August 31, 2004) Added the ability to copy and paste data back into the injection group participation points table.

(October 22, 2004) Modified the calling of a QuickAux file so that after processing the AUX file, the onelines and all open windows are refreshed.

(March 4, 2005) Added log messages notifying the user when the impedance of a branch was changed due to the impedance correction tables.

Help

(April 2, 2004) Added help link information for several features which previously did not have these direct links. Help links allow you to press the F1 key to bring up help information about the dialog you are presently looking at.

Bug Fixes:

File Formats

(March 23, 2004) When reading in a PWB file which contained label information the reading of the PWB file could become very slow. This was caused by an unnecessary sort of the list of labels after each label was added (resulting in a huge overhead of sorting). This has been fixed to only perform the sort at the end of the read.

(April 2, 2004) Fixed potential access violation error that would prevent you from reading in a PWB file. The error occured when you saved a PWB file which stored contingency violations related to interfaces. The PWB file itself was fine, but the read routine was incorrect. This has been fixed. If you get this patch you will then be able to read your PWB file.

(April 2, 2004) When reading in the IEEE common format, transformer taps not equal to one were causing problems. This has been fixed.

(April 20, 2004) Fixed bug where non-transformer branches could be given non-unity tap ratios, which could cause errors in loading the PWB file.

(May 3, 2004) Fixed bug in writing out PTI Version 26 RAW files. An extra comma was written in the tap/angle place holder.

(May 18, 2004) Fixed problem with assigning the metered end of three-winding transformers when reading from a GE EPC file.

(June 21, 2004) When reading in PTI and GE text files, previously we labeled all branches which have different Nominal kV levels at either end as a transformer. This has been changed so that it is treated as a branch unless specified.

(June 21, 2004) Fixed bug when reading in a PTI RAW file which had the transformer impedances specified by the Watt Load loss and the Impedance Magnitude.

(July 8, 2004) Fixed Simulator so that it now supports reading PTI RAW files with longer bus names. Simulator now supports an unlimited name length, while PTI has increased their limit to 12 characters.

(July 26, 2004) Fixed error when reading Post Power Flow Solution Actions which contain Model Condition or Filters. Previously these were being read incorrectly and all post solution actions would show no model criteria.

(July 30, 2004) Fixed problem with assigning the metered end of a transmission line when it is read from an EPC file. Previously it was reversing the way that AC transmission lines are metered.

(August 31, 2004) Added checks to ensure that PTI RAW files which leave entries off the end of a record can be properly read.

(August 31, 2004) Corrected the manner in which the six extra flags at the end of generator records in the GE file are read (including the "baseload" flag)

(September 10, 2004) Added checks to ensure that when deleting objects such as lines, interfaces, injection groups, buses, etc... which may be accessed by results of contingency analysis, ATC, PVQV, or OPF/SCOPF so that references to the objects being deleted are removed. This was causing some intermittent errors, and could even prevent you from saving a case.

(September 10, 2004) Modified the reading of a PTI raw files so that if either the voltage setpoint is 0.0, or the regulated bus number is set to 0, then a generator is set to not be on AVR control. (September 29, 2004) Changed this logic so that if the regulated bus number is set to 0, then we do not turn it off AVR. We assign the regulated bus to be the terminal bus

(October 12, 2004) The DC Loss Multiplier was not being properly stored in the PWB file. This has been fixed so that this value is now stored.

(October 15, 2004) Fixed bug regarding reading of RAW files when the decimal separator is specified as a comma. RAW files always assume that the decimal separator is a period, so the routines were changed to always read this way.

(October 15, 2004) When reading in an old PWB file, the setting regarding whether a continuous shunt was presently stuck at a limit was not stored for files created before continuous shunts existed. The value is now automatically set when reading in a older PWB file. Prior to making this fix, you would open an old solved PWB file and notice some generator Var limit checking occurring unnecessarily.

(October 22, 2004) If language settings were set to use a comma as the decimal separator, it was impossible to read in PTI or GE text input files. This has been fixed. A related bug was making it impossible to edit Case Information Displays or read in AUX files which used commas as decimal separators. Simulator will now use the decimal separator.

(October 27, 2004) Fixed PTI Contingency file read routine so that it treats a line that start with a / as a comment. Previously a / was only considered for an intraline comment.

(December 14, 2004) Fixed an error in the base conversion when computing the magnetizing G and B values from no load loss MW and exciting current for transformer objects.

(December 14, 2004) There was an error in the branch data record when saving out version 23-25 RAW files which neglected to add space preceeded three commas representing no tap information. This has been fixed.

(December 30, 2004) If the user chooses open case and selects a file, then they are prompted to save the existing case. If they choose to save the file, then Simuator would try to open the new case assuming the same file format that was just saved. This would not always be the case, so the open case procedure would fail. This has been fixed.

(December 30, 2004) Fixed a bug where opening a project file from a website through Internet Explorer would end up extracting the case, diagram and script files onto the desktop, regardless of where the actual project file was located. Now it extracts them to the same directory that the project file is in.

(January 28, 2005) Fixed some data consistency requirements that conflicted when reading a GE EPC file and they writing out a PTI RAW file (or vice versa). Requirements about data numbering such as how multi-terminal DC buses are numbered, or how quotations are handled have been fixed. These errors would only appear when reading from one format and then writing out to the other.

(February 23, 2005) Simulator presently does not support having a group of generators on remote regulation control if one of the generators connect to the bus being regulated. In this situation, the generator at the regulated bus will be set off AVR.

(February 23, 2005) Fixing several errors when writing out data to an GE EPC files.

(March 4, 2005) Fixed so that switched shunts set to “Bus Shunt” control will not be changed to “Fixed”. Functionally this makes no difference inside Simulator, but would change how the data is written out to the GE EPC file.

(March 4, 2005) When reading in a case, the flow on the DC transmission lines are initialized using the voltages read at the terminal buses of the line. If the case had been solved using the DC approximation, this initialization was sometimes done incorrectly. This had no effect on the analysis, because as soon as you recalculated the power flow, it would properly set the flows, but it did result in DC line flows appearing incorrect immediately after a case read. This has been fixed.

(March 7, 2005) When reading a PTI or GE case, a phase shifter branch that was set to be off of control would be read in as on OPF control instead. For the power flow this makes no difference, but for users using the OPF this could cause confusion.

(March 14, 2005) Finished off numerous changes to better support writing out the GE EPC file format

(March 24, 2005) Fixed I/O and access violations errors when writing shunt data and transaction data in EPC files. Errors were introduced in March 9 patch.

Auxiliary File Format (SCRIPT and DATA Sections)

(April 2, 2004) When reading in Custom Model Expressions from an auxiliary file (such as a contingency aux file), the variable names were not being read from the file properly. This has been fixed.

(April 2, 2004) It was possible to create a transformer correction table numbered zero via an auxiliary file. This would cause errors throughout the code resulting in divide-by-zero errors. This has been fixed by removing the ability to create a correction table numbered zero.

(May 3, 2004) Fixed bug that causing area transactions for an area to be deleted when creating new buses from an auxiliary file and assigning that bus to the area.

(May 3, 2004) Added auxiliary file support for reading/writing the more advanced Base MW Transactions used in Version 10.0. Multiple transactions may now be defined between two areas with each transaction also have options related to OPF dispatch.

(May 3, 2004) Modified owner case information displays so that when the Shown field is changed, all open case information displays are updated to reflect the change in whether particular owners should be shown.

(May 18, 2004) Fixed error when creating a new bus from an auxiliary file. Previously problems could occur with the assignment of the area or zone of the new bus.

(June 1, 2004) Modified the DCLine object so that it properly exports the object field list from the help menu. Previously it was leaving out several fields.

(June 1, 2004) Fixed script commands which utilize filters so that the check of whether the filter which is named actually exists does not occur until all previous script actions have been implemented. This was because previous script commands may have created and/or deleted a filter meaning that the status of whether it exists or not can not occur until previous command have been done.

(June 4, 2004) Fixed error when processing script commands for solving the SCOPF or OPF which result in another AUX file being loaded. If the AUX file opened a new case it could cause problems because of the new ability in Simulator 10.0 to abort a script while it is in process.

(June 21, 2004) Fixed error when reading in information about the layout of the case information displays from an AUX file. Reading of the sort direction from these AUX files was not working correctly.

(June 21, 2004) Fixed bugs in the DoCTGAction when the actual object described by the action did not exist.

(June 21, 2004) Fixed error when running a script command (such as SolvePowerFlow) which can be set to automatically load another AUX file if the command fails. This was causing a problem in the other AUX file loaded a new case.

(July 30, 2004) Fixed reading the tap ratio from an Auxiliary file. It was not allowing one to set the tap ratio for branches that did not have transformer controls defined.

(November 24, 2004) Fixed a performance problem when reading in a large number of label definitions from an AUX file, or when pasting in this information from an AUX file. A sort was being called after each label insertion which was resulting in very slow performance when reading this files.

(December 14, 2004) Sorting by the ownership percentage of a generator was not working properly. This has been fixed.

(January 28, 2005) Fixed bug in parsing the SetData() and CreateData() script commands. If the valuelist section included any strings containing commas, then the parsing would ignore the enclosing double quotations and incorrectly parse the value list.

(March 31, 2005) When loading in an Auxiliary file as a complete case, Simulator would then try to perform “angle smoothing” on all the transmission lines. This is a good thing if you’re adding a small number of lines to the case, but didn’t make sense when loading a case as an Auxiliary file. This is fixed.

(March 31, 2005) When loading in a generator DATA section of auxiliary file which contained blank entries for the GenLPMW variable. This would cause an error which would result in the read of the auxiliary file being aborted.

(May 10, 2005) Added the ability to using the SCRIPT command Delete to delete MW Transactions.

(June 28, 2005) Modified writing out auxiliary files so that when a numeric field contains a text which includes the field delimiter (spaces) it will always uses quotes.

(June 28, 2005) Writing out the LPVariable information to an auxiliary file or passing it out via SimAuto was not working correctly. This has been fixed.

Oneline Diagrams

(March 23, 2004) Zooming in very close to a contour image would sometimes cause the contour image to disappear. This error has been fixed.

(March 23, 2004) The new text fields related to the oneline include the ability to show the zoom percentage. This value was not correctly shown when using the thumbnail view. The value would show the zoom percentage of the thumbnail instead of the actual oneline. This has been fixed.

(March 23, 2004) Fixed an error which resulted in circuit breakers to sometimes not respond to mouse clicks when using a oneline diagram in conjunction with the thumbnail view.

(April 2, 2004) When zooming in very close to an drawn contour image, the contour image would disappear if you zoomed in too far. This has been fixed so the contour will no longer disappear.

(April 2, 2004) The Show Full button has been fixed so that onelines properly take into account the scroll bars on the oneline diagrams.

(April 2, 2004) After a circuit breaker was set to a size of zero, you could not get the circuit breaker to reappear by increasing its size. This has been fixed.

(April 2, 2004) Fixed an "out of memory" error which could occur when painting a oneline diagram to an extremely large display board. We did not experience this problem until we running diagrams displays boards with resolution on the order of 4096 x 1536 pixels and larger. After fixing this error, the diagrams have now been test up to a resolution of 10,240 x 3076 pixels on an array of 10 x 4 monitors.

(April 20, 2004) Added font scaling factor for use on very large monitor displays.

(May 3, 2004) Fixed a bug in the auto-insert transmission lines routine. When a bus (or substation) had a very large number of lines connected to it, the routine could cause errors. This has been fixed.

(May 3, 2004) Fixed error which would result when using Select by Criteria on unlinked substation objects.

(May 18, 2004) Previously when using the "highlight low and high limits" option for oneline fields (typically in red and blue), Simulator would then save the oneline PWD file with the colors of the fields permanently changed to blue and/or red. This has been fixed.

(July 8, 2004) Fixed bug when trying to save hidden views.

(July 8, 2004) Fixed error with injection group objects. They are now forced to always be rectangular objects and not allowed to be ovals.

(July 8, 2004) When copying the oneline to the clipboard with a color map dialog open, the colormap dialog was being drawn in the wrong location. This has been fixed.

(August 10, 2004) Fixed error with oneline link objects when searching for the filename in the oneline browsing path. Previously it would not properly utilize the oneline browsing path.

(September 10, 2004) Fixed the interface fields so that they properly show the units of MW, MVar, etc... when using a field chosen from the "other field" list.

(November 17, 2004) Enhanced the speed of updating the links of oneline objects linked to transmission lines. When updating a case which had a diagram that contained a large number of unlinked elements, Simulator would sometimes seem to lock-up while it searched through the case trying to link the oneline objects back to the diagram. This search routine has been greatly enhanced.

(November 24, 2004) Added a correction to the Oneline Display Options dialog for the show header and show footer option of the pie charts. These check boxes were reversed.

(February 4, 2005) When auto-inserting generators, loads, or switched shunts, the fields associated with these objects were not properly moving to stay lined up with the object to which they refer. This has been fixed.

(February 11, 2005) Fixed a problem linking DC line objects to the correct data model object when drawing more than one DC line between the same terminal buses on the oneline diagram.

(April 19, 2005) Under some circumstances, a user could be prompted to save a Bus View oneline. This should never happen and has been fixed.

Bus View and Sub View Oneline

(April 2, 2004) The Show Full button has been fixed so that it properly takes into account the buttons at the top of the diagram.
(April 2, 2004) Fixed the accidental panning which would occur when clicking on the far bus "links" on a bus view with a large amount information on it.

(April 2, 2004) Modified so that the cursor will alwasy change to a hand when moving over top of the bus links and substation links on the Bus and Substation Views. Previously this did not occur when in Edit Mode.

(April 2, 2004) When hiding the pie charts on a bus view, the oneline hints for invisible pie charts where still active, however they always displayed a percentage of 50%. This has been fixed.

(July 30, 2004) Colors on the substation view for transformers were being reversed. This has been corrected.

Power Flow Solution

(April 2, 2004) Previously when determine whether to redispatch generation in an area on participation factor control, we would only look at whether the area's ACE was outside of tolerance. This has been changed so that we will also redispatch if any generators are outside of their MW limits and are set to enforce these limits. Previously if a generator was outside its limit, but in an area that was meeting its ACE it would not be brought within its limits. Now this generator will be brought within its limit and the remaining generation will redispatch to make up for this.

(May 3, 2004) Support for the new ability of continuous switched shunts to be treated as PV buses was creating problems in the decoupled power flow (and thus Robust solution method). For now, the treatment of continuous shunts as PV buses during the decoupled power flow is not done.

(May 3, 2004) Fixed error in new Island-based Automatic Generation Control when using area-based participation factors. This was resulting in invalid generator redispatch resulting in unsolvable power flows.

(May 21, 2004) Add support for flagging a situation when a remotely regulating generator was exactly at its MVar limit and the generator was unable to control the remotely regulated bus because no path existed between the generator and the remote bus which did not go through another PV bus. Previously this could cause a repeated message stating that the generator was going to back-off its MVar limit, but it would never move.

(June 1, 2004) Fixed the multi-terminal DC Line model so that it properly handles converters on current-control when solving a DC Power Flow solution. Previously this was causing errors (Note: power-control modes worked fine before, only the current-control caused problems.)

(July 8, 2004) Fixed a bug with DC transmission lines when one of the terminals was a slack bus and the slack angle was non-zero.

(July 8, 2004) Cleaned up some of the message log entries so that you do not see warning messages regarding remotely regulated buses when a generator is on line drop compensation control.

(July 8, 2004) Fixed a memory leak which occurred when we added the support for modeling continuous switched shunts as PV curves.

(October 15, 2004) Fixed a bug which caused bus loads containing constant current/impedance values to move a little when using the island-based generation control. This has been fixed.

(November 17, 2004) When using post power flow solution actions, interfaces with contingent elements would have their flows updated twice unnecessarily at the end of each power flow solution. This has been fixed so that they are only updated once.

(January 19, 2005) Under some circumstances, when all generation in an area is at its maximum limit, a divide by zero error could occur in participation factor control. This has been fixed.

(February 11, 2005) Fixed a bug where including continuous switched shunts with 0 MVAR range (min and max the same) as PV buses in the inner loop caused solution failure. Continuous switched shunts with no MVAR range are now treated as Fixed shunts during the solution.

(April 19, 2005) When a dc converter is taken out-of-service due to the loss of the AC bus to which it was attached, under some circumstances, the power flow solution could fail. This has been fixed.

(May 10, 2005) Updated the multi-terminal DC line converter so that its status can be specified as out-of-service. This is handled similar to the AC system outage at the DC converter.

SimAuto

(May 21, 2004) Fixed initialization of the error string in the ListOfDevices command. Previously in Matlab, this was causing problems.

(May 21, 2004) When Simulator with the SimAuto add-on was executed by a Windows User without priviledges to modify the Windows Registry and Simulator SimAuto had not already been registered on the computer, then Simulator would fail to launch. This has been fixed so that Simulator will still launch, however the SimAuto features of Simulator will not work until a user with proper priviledges registers it.

(July 8, 2004) Modified to return more descriptive validation and execution error messages from script commands.

(October 12, 2004) Removed some extraneous log messages send when starting up Simulator by using a SimAuto call.

(November 17, 2004) Modified so that ListOfDevicesAsVariantStrings SimAuto function call is visible. Previously it was available for use, but the user could not query SimAuto to see it was available.

(December 14, 2004) Fixed error in the SolvePowerFlow script command which resulted the the solution type attempting an AC solution if the solution type was not specified. This was messing up scripts that were using the DC approximation.

(December 30, 2004) When requesting data through SimAuto for objects that are not allowed to be called, an access violation error occurred. Instead it now returns an error string indicating that data requests for the type of object passed are not allowed.

Contingency Analysis

(March 16, 2004) When restoring the reference state in the contingency analysis, the minimum generator MW value was not being properly restored. As a result, when specifying the Maximum Generator MW Response on the Advanced Modeling tab of the contingency analysis, the reference state would not properly reset this value. This will affect contingency analysis as well as the ATC, PVQV, and SCOPF if you are using the Maximum Generator MW Response options. This error has been fixed.

(March 23, 2004) Fixed error resulting in a divide-by-zero in the contingency analysis when running contingencies against a case which had limits of zero in the post-contingency solution limit set.

(April 2, 2004) When using the Produce Report abilities for creating a text report in the contingency analysis tool, we were incorrectly reporting inactive violations even when this option was not chosen. This has been fixed.

(May 3, 2004) Modified the area/zone/owner fields of contingency records so that they return comma-delimited lists of all appropriate elements.

(May 18, 2004) Fixed potential error which could occur when processing a contingency which isolates a generator from it's remotely regulated bus.

(May 21, 2004) Add checks to prevent the insertion or deletion of contingencies when in the middle of running a batch of contingencies.

(June 1, 2004) Fixed bug introduced on 5/21/04 patch which caused the right-click, Insert option on the contingency list to not work.

(June 21, 2004) Fixed errors which would occur when the same Contingency Block was called TWICE inside the same contingency definition. This would cause problems when mixed with Model Criteria definitions.

(July 8, 2004) Fixed bug in Send Combined Results with both Violations and Definitions to the clipboard or Excel. This was not working due to changes made regarding area/zone/owner fields on May 3. It is now fixed.

(July 8, 2004) Fixed bug in using the Set To and Change By calls with Switched Shunts when the existing switched shunts had a present value of zero or are turned off.

(July 30, 2004) Fixed bug with clearing out all the contingency results when utilizing the SCOPF tool and then trying to load in a new set of contingencies. Previously the old SCOPF-related information was not being properly cleaned up and was causing access violations when a new contingency list was loaded.

(September 7, 2004) Fixed error with restoring the reference case when continuous switched shunts become stuck at a min or max var limit. This would only be a problem if the subsequent solution needed additional var output from the generator in order to solve.

(September 29, 2004) Fixed an error which would occur when restoring a system state after a contingency which involved the outage of an entire multi-terminal DC transmission line. This would result in the multi-terminal DC line being completely outaged even after restoring the reference state.

(February 23, 2005) When specifying a contingency block as part of a contingency and then specifying that the status of the Block of ALWAYS or NEVER, the checking of the model criteria was still occurring. This has been fixed.

(March 14, 2005) Fixed bug with the contingency comparison dialog so that it would properly work when choosing to use the present results as either the comparison or controlling case.

(March 14, 2005) Modified to reset the comparison contingency records when choosing to filter results based on the present limit monitoring settings.

(June 7, 2005) Fixed bug that would occur when the first contingency the list did not contain any elements, or the elements did nothing (such as opening a line that was already open). In these situations when using the DC approximation for the power flow, or when using one of the linearized contingency calculation methods, the contingency results could be calculated wrong. The results would be very strange (100,000% overloads and such).

Optimal Power Flow (OPF) and Security Constrained OPF (SCOPF)

(April 2, 2004) Corrected the number of active contingencies box on the SCOPF dialog. It was previously always blank.

(April 20, 2004) Fixed problem resulting from a hardcoded constant in the OPF and SCOPF routines. Previously the "unenforceable constraint cost" for the Area ACE equation was internally set to 5000 $/MWhr. This meant that if the unenforceable constraint cost for enforcing transmission line or interfaces was set to a value higher than this, then the Area ACE equation would ignored because violating it was considered "cheaper" than violating the line flow. The OPF has been modified so that unenforceable ACE cost is always TWICE as big as the cost of enforcing the line and interface constraints.

(May 3, 2004) Fixed bug in which flow sensitivities were not being calculated correctly for some interfaces that involved phase shifters. This occurred if the flow direction of the interface was reversed. This effected the PTDF/TLR calculations as well as LP OPF calculations.

(May 3, 2004) Modified phase-shifter control status to be either None, Power Flow, or OPF. Previously when trying to utilize phase-shifting transformers for OPF dispatch it was very unclear how to set Simulator's flags. A control can not be used in both the power flow algorithm and the linear program for OPF dispatch, therefore the new control status is more consistent.

(May 3, 2004) Fixed a bug in the SCOPF which would cause an access violation when using a DC approximation and the DC power flow failed to solve if it experienced a "> 360 degree" angle difference.

(May 21, 2004) Fixed problem caused after loading in a case that was saved with SCOPF results. When coming back in to the SCOPF dialog, an infinite loop would occur which would close Simulator.

(June 21, 2004) Improved LP detection of cycling to help with slow convergence under certain situations.

(June 21, 2004) Cleaned up problems with the DC OPF not always properly enforcing active phase shifting transformers.

(July 8, 2004) Fixed bug in which generator cost models with zero width segments could cause excessive convergence.

(July 8, 2004) Load and study transaction controls were not being written correctly when the controls were saved. This is now fixed.

(August 31, 2004) Fixed error which could occur when initializing an SCOPF run with an OPF solution. If the number of contraints encountered by the SCOPf was less than the number the OPF saw, this would cause an error. This has been fixed

(August 31, 2004) Fixed error in sensitivity calculation which could effect the monitoring of interfaces in the OPF/SCOPF tool when one of the branches specified in the interface is connected to the slack bus.

(September 29, 2004) Fixed an error which occurred when you added a dispatchable transfer which was between two areas inside the same Super Area. These transfers should be ignored if the Super Area is on control, but were incorrectly being dispatched messing up the OPF/SCOPF solution.

(November 12, 2004) Modified so that the ACE calculation for a Super Area which includes all areas in the entire case always is calculated as exactly zero

(November 12, 2004) Fixed bug related to fix on Sept 29 regarding transfers between areas in a super area. This fix from Sept 29 was not complete and was resulting in transactions not being used in the OPF when both the buyer and seller area of the transactions were on OPF control independently.

(November 17, 2004) When using post power flow solution actions, Simulator's OPF algorithm with constantly resolve the power flow according to the post power flow solution actions. In doing the solution, the generation was being moved a small amount. This was causing some difficulty with convergence in the OPF algorithm. This has been fixed by modifying the post power flow solution actions to not move generation when called from the OPF algorithm

(December 30, 2004) Added storage to the PWB file of the setting called "Enforce Line/Transformer MW Flow Limits (not MVA)" on the Line/Transformer Constraints options. Previously this was not stored in the PWB file.

(February 23, 2005) Modified the way that a dispatchable transaction which was between an area on OPF control and another area not on OPF are handled to better handle this situation.

(February 28, 2005) When the OPF or SCOPF encounters unenforceable Area constraints, such as when an area did not have enough generation to meet its own load, then this power must be made up at the system slack bus. In this situation, when using the DC approximation, the output of the slack bus was being incorrectly set resulting in a bus mismatch. The remainder of the solution was correct, but the output of the slack bus was being calculated wrong. This has been fixed.

(March 21, 2005) Modified the Linear Programming algorithm so that if it is having difficulty converging it will exit the LP loop and do an additional power flow solution. This helps with convergence in some situations.

(May 10, 2005) Removed the restriction that there be a maximum of 500 simultaneously binding line constraints in the linear program. The limitation in version 11 has been removed completely. The version 10 patch has increased this limitation to 10,000.

(May 25, 2005) When using the script command SolveFullSCOPF(OPF, success.aux, failure.aux), if the SCOPF ran out of LP iterations it was incorrectly executing the success.aux Auxiliary file anyway. This has been fixed.

Available Transfer Capability (ATC)

(April 20, 2004) Fixed error in ATC transfer limitation reporting when an oscillation in the Iterated techniques started occurring.

(May 18, 2004) When using the ATC to solve multiple scenarios, you can right-click on the scenario grid and choose to Determine ATC for selected scenario. Previously when the user responded "NO" to the prompt which would appear, Simulator would move to the new scenario anyway. It would then reset back to where is started. This was unnecessary and has been fixed.

(May 18, 2004) Modified the tolerance used when ramping out the transfer in the iterated ATC solution methods. The tolerance now used is one-half of the minimum AGC Tolerance of the two areas used in the transfer.

(May 21, 2004) Fixed the ATC calculation so that it properly updates the list of monitored lines at the start of each calculation. Previously in Simulator 10.0 if you ran an ATC run, closed the ATC dialog, closed in a transmission line, and went back into the ATC dialog, then the line which was just closed in would not be monitored.

(August 31, 2004) Added prevention of trying to create an Excel sheetname with a name longer than 31 characters when writing ATC results to a spreadsheet. This causes an error in Excel.

(December 14, 2004) When using the ATC Solution method Iterated Linear then Full AC, the limit set specified as the "post contingency limit set" was not being properly used. It was instead using the normal ratings set. This has been fixed.

(April 7, 2004) Fixed error when opening the ATC dialog after having previously run the ATC using one of the iterated methods with injection groups as they buyer/seller.

PV and QV Curve Tool (PVQV)

(May 18, 2004) Fixed error in PV Curve which would occur if Simulator was unable to save the results to the file which processing. This might occur if the file was open by another application, an invalid path was specified, etc... This would result in the PV run aborting. This has been fixed so that the PV run will still finish (although obviously the file will not be saved.)

(July 8, 2004) Modifications were made to fix the behavior of the integrated PV/QV curve tool.

(July 26, 2004) Fixed error on the "Plot these quanitities" case info display so that the Toggle All Yes and Toggle All No values were correctly available. Previously there was a only a Toggle All which would just flip all the values to be opposite of present settings.

(July 26, 2004) If the base case was the critical one, the critical base state aux file was not being saved; the base case state file was being saved only for critical contingencies. This has been fixed.

(July 30, 2004) Modified to save both AUX and PWB files when saving critical states in the PV Curve tool. Errors were being seen when trying to load back in a large AUX file.

(August 31, 2004) Modified the PV tool to add a user option regarding whether to save states as either PWB or AUX files or both.

(September 10, 2004) Removed references to qvSave from the auxiliary file data sections associated with PVCURVE_OPTIONS. This was not used anyway.

(September 10, 2004) Modified the PV Curve Tool dialog to properly set the source and sink when the dialog is opened or after reading in an AUX file.

(September 10, 2004) Modified the Load Options button on the PV Curve Tool dialog so that it properly allows you to read in an AUX file which creates new objects (such as contingencies, injection groups, etc...)

(September 10, 2004) Fixed archiving of the critical and base case states so that they are saved according to the settng the user specifies regarding saving as an AUX or PWB file.

(September 29, 2004) Fixed the specification of switched shunt tracking in the PV tool so that the toggle all YES and NO works properly.

(October 15, 2004) Modified the setting of the power factor used for scaling load so that non-integer values can be entered. The value was always stored as a floating point number, but the dialog only allowed specification of integers.

Sensitivity Dialogs (PTDFs, TLRs, GSFs, Flow and Voltages, Losses)

(April 2, 2004) One the TLR/GSF Sensitivities and Flow Sensitivities dialogs, When clicking the "Set Sensitivities of Out-of-Service Buses Equal to Clostest" button, the buses not more than 2 tiers away from an inservice bus were not being properly set. This has been fixed.

(April 20, 2004) Corrected potential access violation when doing the TLR sensitivities with a power flow set to use the DC approximation.

(April 20, 2004) Fixed intermittent error in calculating TLR sensitivites for an interface which contained outage elements.

(May 3, 2004) Fixed bug in which flow sensitivities were not being calculated correctly for some interfaces that involved phase shifters. This occurred if the flow direction of the interface was reversed. This effected the PTDF/TLR calculations as well as LP OPF calculations.

(July 26, 2004) Fixed error on the TLR/GSF dialog which was causing interfaces that contained contingent elements to double-count the contribution from the contingency. This is now fixed for both the single element calculation as well as for multiple elements.

(September 29, 2004) When performing a PTDF calculation using a Super Area as the buyer or seller, if any of the areas inside the Super Area did not have any generation, then you would receive an error saying that the "buyer and seller" were in different islands. This error was incorrect and has been fixed.

(March 14, 2005) Fixed error in setting the out-of-services buses to the sensitivity of the closest bus.

User Interface Dialog Modifications

(April 2, 2004) Setting the Scale property of an injection group was not working properly. This made scaling by injection group impossible. This has been fixed.

(April 2, 2004) The minimum and maximum bus MW Marg Cost fields were not being calculated correctly for owners. This is now corrected.

(April 20, 2004) Fixed access violation error when creating an equivalent. Came from trying to solve load flow which had not been initialized until you first when to run mode. We have now removed the automatic solution prior to creating an equivalent.

(April 20, 2004) Fixed bug in the toolbar button for setting the "snap-to-grid" drawing option for the oneline in Edit Mode.

(May 3, 2004) Fixed problems with prompt dialogs appearing behind the Auto-Insert Contingencies dialog and the Area Information Dialog when the Area/Zone/Owner filter dialog was opened.

(May 3, 2004) Fixed problems with defining Base Transactions on the Case Information, MW Transactions (Base) display. The dialog was not properly handling the fact that multiple transactions may now exist between areas.

(May 3, 2004) If a switched shunt was assigned to an area/zone that was different than the terminal bus, then you could not change the area/zone to be equal to the terminal bus. This bus has been fixed.

(May 3, 2004) Added a new option to the right-click dropdown menu of the interface case information display which allows you to set the limits equal to the sum of the transmission line element limits in the interface.

(May 18, 2004) Fixed various bugs related to the storing the MW Base Transactions in auxiliary files when the transaction was disabled. Also fixed bugs related to comparing disabled transactions using difference flows.

(June 21, 2004) Fixed bugs caused when deleting Area Transactions and then reinserting them.

(July 8, 2004) It previously was possible to enter a bus name that was blank via the bus edit mode dialog. This has been modified to not allow this.

(July 8, 2004) Added the prevention of defining injection groups with the same name. Previously this was possible and should not have been allowed.

(July 26, 2004) Fixed Bug with Advanced LODF Calculation ability. This was causing an access violation.

(July 30, 2004) Fixed bug in select by criteria dialog when selected by layers which were not visible.

(July 30, 2004) Fixed access violation which occurred when merging two buses together so that the new bus was assigned to be one of the buses being merged together.

(July 30, 2004) Modified the new case menu option so that it correctly clears out the advanced filters defined by the case.

(August 10, 2004) On the case information displays for lines, the B,C,D,E,F,G, and H limits were showing the A limit. This error was introduced on July 26.

(August 10, 2004) When creating a new bus, the bus name was being truncated to 10 characters unnecessarily. This limitation has been removed so that buses may be created with unlimited character length.

(September 29, 2004) Fixed an intermittent bug which would occur after right-clicking on a case information display, canceling the popup-menu, and then not clicking anywhere on the case information display prior from moving away from it. This would result in nuisance access violations until the case info display was closed.

(October 12, 2004) Fixed error in setting the unspecified MW interchange for areas when creating an equivalent.

(October 12, 2004) The option on the Base MW Transactions dialog called "Clear Transactions and auto-insert tieline transactions" was only working correctly when used on a system using the full AC power flow equations. This has been fixed so that they feature may be used on DC power flow models also (DC approximation).

(October 22, 2004) On the System Scaling Dialog, the totals for Load MW and Load MVar was being calculated incorrectly if you were using contant current or impedance loads and using the DC approximation.

(October 27, 2004) Fixed bug with writing out the transformers added when using the Present Case Topological Differences from Base Case. Previously it would always list all transformers as having been added to the case.

(November 4, 2004) Fixed the scaling dialog so that the Area, Zone, and SuperArea Lists allowed for a Toggle All YES and a Toggle All NO.

(November 4, 2004) Fixed bug that would occur when deleting a transmission line that was a zone tieline. The zone tielines were not being properly updated when this occurred.

(November 4, 2004) Fixed bugs that could occur when deleting loads and shunts. If the load or shunt was defined as part of a Model Condition, Global Contingency Action, Contingency Block, or Post Power Flow Solution Actions, then the case could not be saved.

(November 5, 2004) Modified the edit mode generator dialog so that it properly resets the Min/Max MVar output after changing the MW output of the generator.

(November 5, 2004) Modified the System Scaling dialog so that when scaling an injection group, the area unspecified MW interchange is not modified. Previously the unspecified MW interchange would change by the amount that gens/loads in the area were moved.

(November 12, 2004) Fixed bug introduced in fix on Oct 27 regarding showing of topological differences of transformers in a case.

(December 14, 2004) The limit group dialog was showing the checkbox Treat Transmission Line Limits as Equivalent Amps in the opposite way it should have been. This has been fixed.

(December 14, 2004) When navigating to a view which had saved the contour information with it, the appropriate new color map was not being utilitzed if it was different than the color map used on a previous view. This has been fixed.

(December 14, 2004) An error could occur when tapping a branch that was already part of a multi-section line. This has been fixed.

(December 14, 2004) When tapping a branch that was already part of a multi-section line, Simulator would always add the additional lines created to the multi-section line. To better signify this, the checkbox regarding treating the new sections as multi-section line is now disabled on the dialog when you have selected part of a multi-section line.

(January 14, 2005) Fixed an error when right-clicking and choosing insert on the list of area to area transactions. This was sometime resulting in extra transfers being added to your case. The extra transaction was always set to 0 MW, so it was not causing solution difficulties, but it was creating the extra record.

(March 4, 2005) Fixed intermittent bug when using the custom case information display which occurred when deleting an entire sheet on the display.

(March 28, 2005) Correcting access violation when writing topological differences to an AUX file for transformer changes

(March 28, 2005) Fixed a nuisance access violation which could occur when closing the Default Drawing Values form by clicking on the X in the upper-right corner of the dialog.

(April 7, 2004) When using the Difference Flows feature, the Super Area information was not being stored correctly.