What's in the Simulator 8.0 Patch?

PowerWorld Simulator 8.0 Patch addresses problems that were detected in the program after its release and introduces some new functionality. These modifications are listed here.  

The patch was last modified March 13, 2003.  

Minor Updates made to this patch are noted below along with a date and explanation.  This patch was first introduced on February 7, 2002.

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

Case Information Displays

• (February 8, 2002) The column headings and row numbers of the presently selected cell are now highlighted in the case information displays.
• (February 19, 2002) The Line Length field of a transmission branch was not displaying the correct value.  This has been fixed.
• (February 22, 2002) Enabled the pasting of transfer matrix data from a spreadsheet.
• (July 3, 2002) Added ability to add MW and Max MW fields for the area-slack generators in the area records view.
• (July 17, 2002) On several Bus displays and on the Quick Power Flow List, the mismatch values were sometimes reported to the user interface incorrectly.  The case information display specifically designed to show Mismatches always showed the correct values however.  Simulator has been fixed to show mismatches correct in all situations now.
• (July 17, 2002) Modified the DC Lines case information display to show both DC Lines and Multi-terminal DC lines on separate tabs.
• (July 23, 2002) Added a column to zones and areas that will show the MW Load - weighted average of bus marginal costs in the zone or area.
• (August 12, 2002) Made Min and Max MVAR output of a generator enterable fields.
• (August 14, 2002) Added Area Name and Area num fields available on a list of Zones.  The Area Name (or Number) will return a comma-separated list of all areas that are inside this zone.  Similarly, Zone Name and Num were made available on a list of Areas.
• (August 16, 2002) Modified the local menu of case information displays so that the Insert option is enabled regardless of where on the display you right click.
• (February 19, 2003) Fixed bug which was causing the admittance matrix (Y-bus) to not be correctly updated after changing the nominal MVAR of a switched shunt object.

Oneline Diagrams

• (February 7, 2002) Interface pie charts displayed an incorrect percentage.  The value was off by 100.  For instance, a percentage of 765% would be displayed when the correct percentage was 7.65%.  This error has been fixed. 
• (February 7, 2002) When calculating an in-line fault, Simulator creates a temporary bus to represent the fault point on the transmission line.  Simulator also changes the oneline diagrams to reflect this addition.  This works correctly, however an error would occur when you go to save the case or oneline.  For saving a case, these errors have been corrected by automatically clearing a fault prior to saving a case. For saving a oneline diagram, the error was also corrected.
• (February 19, 2002) When choosing to show MVAR flows, the pie charts would appear as PTDF percentages instead of line loading percentage.  This has been fixed.
• (July 3, 2002) Fixed bug that was incorrectly writing out information about an Injection Group oneline object so that the injection group was unlinked after reading back in the diagram.
• (July 3, 2002) Modified Bus Views so that the kV value of the bus will be refreshed as you make changes to the power system.
• (July 3, 2002) The default drawing value settings for adding line fields to transmission branches while inserting them were not being used correctly.  This has been fixed so that the fields are added as desired.
• (July 17,2002) Modified the Bus View Oneline so that it shows a representation of the Multi-Terminal DC lines.   
• (July 31, 2002), (August 7, 2002) When inserting a new pie chart on a oneline, sometimes this would incorrectly set the MVA limit of the line to zero.  This has been fixed.
• (July 31, 2002), (August 7, 2002) When inserting a circuit breaker on a oneline, sometimes this would incorrectly override the status of the line and set it to closed.  This has been fixed.
• (August 8, 2002) When reading in a oneline diagram which had a series capacitor field which was unlinked, an access violation error occurred.  This has been fixed.
• (August 9, 2002) When unchecking the option "Animate Size" on the Animated Flows tab of the Oneline Display Options, flow would still appear on lines which were out-of-service.  This has been fixed so that no flows appear.
• (August 9, 2002) When moving your cursor over a DC line in the bus view, an access violation would occur due to the Show Hints option.  This has been fixed.
• (August 12, 2002) Insert Connected Buses option would not work if there were any unlinked bus objects on a oneline diagram.  This has been fixed. 
• (August 14, 2002) When right clicking on an object and choose Add new fields around selection, settings regarding Delta Per Mouse Click were not being implemented correctly.  This has been fixed.
• (August 16, 2002) Modified the graphical insertion of new transmission lines, generators, loads, and switched shunts so that it is more difficult to accidentally insert a new power system record when the intention was only to draw a graphic of an existing one.
• (August 16, 2002) When manually drawing in transmission line object and using the Default Drawing Values settings to automatically insert fields at the from and/or to bus end of the line, sometimes the fields would get put at the wrong end of the transmission line.  This error has been fixed. 
• (December 10, 2002) Fixed a bug that resulting in the anchoring of recently added display objects to be lost after saving a PWD file.
• (March 1, 2003) When using the "Show Oneline Hints" option in Simulator, oneline diagrams which contained unlinked transmission lines would result in nuisance access violations.  No harm came from the error.  The error will no longer occur after this patch.
• (March 1, 2003) When reading in oneline diagrams which contain memo objects, the oneline display would not be properly initialized.  This resulted in many memos appearing even though they should have been hidden because you were not zoomed in on that part of the display.  This has been fixed.

File Formats

• (February 8, 2002) When reading the Version 7.0 ATC Options text file, an error occurs when reading the MAXMWLIMIT value from the file.  Simulator tries to read this value as an integer instead of a floating point number.  This error has been fixed in this patch version.  As a work-around, you can change the value specified in the text file for MAXMWLIMIT to be an integer (e.g. use "9999" instead of "9999.00")
• (February 19, 2002) When reading GE EPC files, the transactions data was not always being assigned properly.  This has been fixed.
• (February 19, 2002) A rare bug that could occur when writing 3-winding transformers to the PWB file format was fixed.
• (February 19, 2002) An incorrect data correction was occurring that caused a voltage controlling transformer to be changed to a MVAR controlling transformer.  This bug would only occur if the control range for voltage controlling transformer was larger than 1.0 per unit, a very rare occasion.  This was changed so that the control range must be larger than 2.0 to be changed to a MVAR controlling transformer.
• (May 15, 2002) Modified the Advanced LODF writing procedure to include comments regarding the flow and OTDF values.
• (June 19, 2002) Fixed bugs regarding the reading label information from an auxiliary file.  List Index Out Of Bounds and Range-check errors sometimes occurred.
• (July 3, 2002) Fixed errors in writing out multi-terminal DC lines to a GE EPC files.
• (July 3, 2002) Fixed errors that occurred when a PTI RAW file with multi-terminal DC lines is read in and then a PWB file is written out from this RAW file. 
• (August 2, 2002) When reading in transformer test data from a PTI version 27 or higher file, it was possible to have encounter a divide by zero error in the calculations of magnetizing impedance.  This has been fixed and no errors will be encountered now.
• (August 14, 2002) An error would occur when encountering comments at the end of lines when reading from a PTI RAW file.  This has been fixed.
• (September 11, 2002) The "fixed cost" part of a piece-wise linear cost curve previously was not being stored in the PWB file.  This has been added to the PWB file and will be saved and read in the future. 
• (November 5, 2002) Problem encountered when reading in a PTI version 25-27 file which had no transformer control records.  This has been fixed.
• (November 5, 2002) A problem occurred sometimes when saving three-winding transformer data to an EPC file.  This has been fixed.
• (December 10, 2002) Fixed an error related to converting PTI files with fixed tap ratios.
• (February 6, 2003) Fixed errors in writing out the PTI format for three-winding transformers and for cases with multiple switched shunts at a single bus.

DATA Section of Auxiliary Files

• (February 8, 2002) Changed reading of interface, contingency and other subdata sections of the Auxiliary DATA sections.  Previously, if an error was encountered in these sections, then the read of the auxiliary file would just stop.  Now, an error will be reported to the log, but the read of the file will continue.
• (July 31, 2002) When reading in DATA section of an Auxiliary File which contained interface definitions with Zone to Zone elements, the zone to zone elements were not read correctly.  This has been fixed.
• (August 12, 2002) If a blank line was found immediately after the DATA declaration line, but before the Data Section starting string {, an error would occur in reading the auxiliary file.  This has been fixed.
• (February 19, 2003) Fixed bug which was causing the admittance matrix (Y-bus) to not be correctly updated after changing the nominal MVAR of a switched shunt object.
• (March 1, 2003) When reading in auxiliary files which contained Reactive Capability Curve data in the Generator SUBDATA sections, the program would not immediately enforce those curves until the generation moved a small amount.  This has been fixed to immediately enforce the limitations.

SCRIPT Section of Auxiliary Files

• (February 22, 2002) The CTGSolveAll contingency action was not working properly.  An error would occur canceling the execution of the script.  This has been fixed.
• (April 16, 2002) The OpenCase() action was not working correctly with all file formats.  This has been fixed so that all power flow formats can be opened from the script.
• (June 14, 2002) Fixed all script commands which enter in numbers with a decimal point so that they are supported.  This would cause a syntax error notification.
• (June 14, 2002) Fixed bugs in syntax error-checking for the Scale, Combine, Move, DiffFlowMode, and Fault.
• (June 14, 2002) Allowed better error checking in the LoadAux() or LoadData() commands.
• (August 14, 2002) When using the OpenCase() action with a GE EPC file, message dialogs would appear asking questions regarding the opening of the file.  This dialogs have been removed when reading from a script.
• (January 7, 2003) An error occurred when saving the "Load-weighted average price" for zones or areas when using the SaveData() script command.  This has been fixed.

Power Flow Solution

• (April 2, 2002) Several improvements were made to better handle groups of generation acting together to control remote regulation.
• (July 31, 2002) Added improvements to the power flow algorithm when closing in a multi-section transmission line.
• (August 8, 2002) Modification to remote voltage regulation from generators connected by zero-impedance branches.
• (August 9, 2002) An error message would occur when the slack bus was set to remote regulation and the path between the slack bus and the remote bus was broken.  This error message was removed because remote regulation from the slack bus is never allowed anyway.
• (February 18, 2003) Modified the abilities of Simulator when creating separate islands so that when an island is "dead" because no generation exists, it will be brought back to service after a generator inside that island is closed.  This generator will then be chosen as the slack bus for that island. 

OPF

• (April 2, 2002) Fixed error which sometimes occurred when generators had min and max MW outputs which were equal.
• (July 23, 2002) Added a column to zones and areas that will show the MW Load - weighted average of bus marginal costs in the zone or area.
• (August 12, 2002) The OPF was ignoring the disabled setting for a Limit Group and monitoring elements of the group anyway.  This has been fixed.
• (December 17, 2002) Buses where power injections would have  a very small impact on binding transmission constraints were previously ignoring the impact of the transmission constraints on the bus marginal prices under the assumption that the constraints would not impact prices at these buses.  This threshold sensitivity was 0.003 (meaning it would take a 333 MW injection to result in 1 MVA change on the line flow).  After further use, it was found that this sensitivity needed to be reduced to 0.00002 (50,000 MW injection for a 1 MVA change) to avoid small LMP errors.
• (December 17, 2002) In generator displays, the marginal cost values shown at buses with generators at cost break points were sometimes confusing.  This has been changed.

Contingency Analysis

• (April 2, 2002) Fixed bug regarding the MVA Convergence tolerance setting under contingency analysis or under a specific contingency. The value was off by the SBase (normally a factor of 100)
• (May 15, 2002) Fixed a bug in Contingency "Produce Report" writing which was causing contingencies with no violations to be listed when this was not desired.
• (May 15, 2002) Modified the OPEN BUS contingency action to properly handle makeup generation.
• (June 19, 2002) Fixed bug which caused the processing of contingencies during the QV curve tool to be skipped.
• (August 16, 2002) When performing linearized contingency analysis and also monitoring for interface MW limits, under some circumstances an access violation would occur in Simulator.  This bug has been fixed.
• (January 17, 2003) The contingency actions which open/close a switched shunt were not behaving correctly.  This has been fixed.

Simulation

• (April 16, 2002) Fixed bug that was causing simulations to not end correctly when the endtime was reached.
• (April 16, 2002) Fixed bug that was causing the incorrect storage of the start, current, and end times and days for the simulation.

Fault Analysis

• (April 2, 2002) Improved the interface of fault analysis.
• (April 2, 2002) Fixed an access violation which would occur during an in-line fault calculation.
• (November 5, 2002) Fixed bug in displaying line-to-line fault current in fault analysis dialog.

Equivalencing

• (June 19, 2002) A few bugs regarding the removal of transmission system elements regarding three-winding transformers, interfaces, and multi-terminal DC lines after an equivalent power system is created were fixed.
• (August 8, 2002) Modified equivalencing feature so that the area ACE remains the same after equivalencing as before.  Previously it would change if some areas were removed from the case or due to the equivalent shunts created.  ACE is maintained by modifying the unspecified area interchange values.

User Interface Dialogs

• (July 3, 2002) Added more significant digits to the series capacitor impedance on the line dialogs.
• (March 13, 2003) When using the System Scaling options with the "Enforce ACE" option checked, even areas which were not scaled would have their generation moved.  This bug has been fixed.