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Simulator 17 Patches

New Features

Bug Fixes

Date

January 21, 2015

Bug Fixes

  • Transient Stability: Fixed a bug in Distributed TS. When an error occurred with COM, it was obscured by a secondary access violation; this is now resolved.

December 22, 2014

Features and Improvements

  • File Formats: When loading a RAW file if a bus is marked as a slack bus, but does not have any generators connected to it, Simulator will now automatically remove the slack bus designation and write a warning to the message log.

November 17, 2014

Bug Fixes

  • Transient Stability: Prevent storing transient limit monitor violations twice to a PWB file. If older files are read where there is the possibility of multiples of the same violation being stored, check for and remove any duplicates.
  • Transient Stability: Fixed error in keeping track of the transient contingency results for "Total Gen MW Tripped". Value was being calculated by multiplying the generator per unit power by the SYSTEM MVABase instead of the machine MVA Base.
  • Transient Stability: Fixed potential error when using a negative END time in a transient stability simulation.
  • Transient Stability: The Transient Stability Dialog was preventing a start or end time which was negative. You could specify a negative time in the case information display showing multiple contingencies, but the edit box for Start and End Time on the dialog was always limiting those values to between 0 and 9999. This has been fixed so negative times may be entered.

November 10, 2014

Bug Fixes

  • Transient Stability: For GGOV1 governor, a when Ka = 0 the governor doesn't make sense because in this situation the output of the governor will NEVER go up. Even as it swings down during a simulation it is then stuck at the lower value forever. Ka=0 is rarely entered in input data but when it is, the intent is clearly to disable the rate limiter, so the Ka term is now ignored if Ka<=0. Also modified GGOV1 to ignore the rate limiter if Ta=0.
  • User Interface Dialogs: Fixed a bug with the Bus View opening from the Owner Dialog Generators tab.

October 30, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug that when in the dialog you were renaming the IG it was adding a copy of the IG that was "Renamed".
  • Power Flow Solution: The power flow might fail to converge if an SVC is located at a disconnected bus. This has been fixed.

October 16, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): When using the script command OpenCase() and the file loaded was invalid, then after completing the script command the power system case will be empty. This was causing an access violation which has been fixed. In addition to fixing the bug, we also added additional error messages to help the user notice that the opening of the case failed.
  • Case Information Displays: Modified case information displays so that the background color outside of the region occupied by rows and columns would obey the color of the background of normal cells in the table. Previously these parts of the grid would appear as white regardless of the colors chosen for the displays.
  • Contingency Analysis: When keeping track of the contingency result that returns the amount of "Total Islanded Load MW", we sum up the amount of load MW at any bus whose bus status is Connected in the reference state and then disconnected in the contingency solution. There was a bug that even loads which had a Status of OPEN in the reference state were included in this summation. This has been fixed.
  • File Formats: There as an error in writing out VSC DC Lines to the RAW file format. This has been fixed.

October 14, 2014

Bug Fixes

  • Optimal Power Flow (OPF): Fixed a bug with numerical tolerances that are too small in the area constraint of an OPF solution.
  • Transient Stability: There was a problem with OOSLEN line relay that was causing an access violation when the relay do not have any data. This has been fixed.

October 10, 2014

Bug Fixes

  • Transient Stability: Fixed error in LHVRT and LHFRT models which could cause the generator to trip inappropriately.

October 8, 2014

Bug Fixes

  • Case Information Displays: When using a piecewise linear cost function for a generator, Simulator continues to use the the "Cost Shift" and "Cost Multiplier" fields to determine the cost function. The case information display however would show these fields grayed-out indicating that these fields were not used. This graying-out error has been removed.
  • Optimal Power Flow (OPF): Fixed a tolerance issue that was causing an infinite loop in the OPF solution.
  • Transient Stability: Fixed an error in the SVSMO3 SVC model current calculations.
  • Transient Stability: Fixed reporting of the "Total MW Load Tripped" during a transient stability contingency when using the CMPLDW model.

October 3, 2014

Features and Improvements

  • Transient Stability: Added error checking for WT3G2, WT3G, WT4G, WT4G1 and REGC_A so that if LVPL=0 then it ignores the low voltage power logic
  • Transient Stability: For LD1PAC, when fuvr=0 we were still reporting transient stability events related to the pickup of the under voltage relay even though it would never actually open anything. This has been fixed to no longer report these events if fuvr=0.
  • Bug Fixes

    • Transient Stability: fixed errors in using a CIM6 motor model which resulted in an access violation
    • Transient Stability: When reading a DYD file, netting records which had a line of text listing only ONE bus listed were not being properly read (2 or more worked fine). This has been fixed to properly read the buses and disable stability models.
    • Transient Stability: For generator transient stability models of SVCs, any MW output of the generator was not properly accounted for in transient stability. This has been fixed.
    • Transient Stability: Added a fix for the previous patch which ignored CMPLDW models which were negative.
    • Transient Stability: modified SVCWSC and VWSCC to ignore the fast override block if DV=0.
    • Transient Stability: Fixed error in current control of the CONV_Adelanto and CONV_IntMtnPP multi-terminal DC line transient stability model.

October 2, 2014

Bug Fixes

  • Power Flow Solution: Fixed an issue with the SVC solution. When the SVC was hitting MVARS or Reactive current limits it was oscillating a lot causing to iterate the voltage loop until the limit. Now it does not oscillate.
  • Transient Stability: Fixed error in handling transient stability DC line equations when the voltage controlling converter changed during a stability run because the original voltage controlling converter was unable to maintain the voltage schedule.
  • Transient Stability: Fixed error in the PDCI transient stability models that occurs for the south-north flow.
  • User Interface Dialogs: Previously after defining a piece-wise linear cost curve for a generator it was difficult to delete the points in the curves globally. Simulator would attempt to always maintain one MW/Price point in the curve to be "helpful" to the user. While this prevents the erroneous input information of specifying a CostModel of Linear without specifying points on the curve it was more annoying than helpful. The user interface has been modified to allow a user to delete all price points now and the OPF and Economic Dispatch algorithms have been modified to capture this situation and ignore generators specified as a Linear model but without a curve - treating this the same as a cost model of None. The easiest place to delete all points is in the Model Explorer under Optimal Power FlowBidsGenerator Bid Curves. Alternatively it can be done running the script command Delete(GenBid);

September 30, 2014

Bug Fixes

  • Transient Stability: Modified the Power-Speed curve on the WT3E and WT3E1 wind turbine so the power is in percentage of Rating Power. Previously we were using percentage of "Pmax".
  • Transient Stability: Fixed error in validation check when looking for small motors

September 27, 2014

Features and Improvements

  • Transient Stability: Added error checking for using a distribution equivalent which could not support the load specified. This was caused because the distribution equivalent impedances are given on an MVABase that is proportional to the MW of the load. In a situation which had a load of 2.0 MW and 120 Mvar, the load would exceed the maximum power transfer of the distribution system because the Mvar values was so huge relative to the MW. An appropriate error message will now be shown.
  • Transient Stability: Modified to not model motors which are less than 0.01 MW and added appropriate warning message to indicate this

September 26, 2014

Features and Improvements

  • File Formats: When reading hdbexport CSV files, modified the prompt regarding unrecognized CBTyp entries. Dialog will appear but check-box on dialog will be available to specify if user choices should be saved to registry for use when loading future CSV files. This will be checked by default. In addition, an extra confirmation prompt appears if the user choices will result in a case with no Breakers.
  • Transient Stability: Modified the validation check for GEWTG machine so that if the electrical model is EWTGFC or EXWTGE, but the fcflag does not match the expected value (0 for EXWTGE and 1 for EWTGFC), then the auto-correction routine will change the fcflag to match the expected value. The assumption is that the user specification of an electrical model is more reliable than setting of fcflag to 0 or 1.
  • User Interface Dialogs: modified the Set Selected Field Inside a Network Cut dialog so that the check box "Require paths to be energized" is checked by default.
  • Bug Fixes

    • Transient Stability: Fixed error when using the FACRI_SS switched shunt stability model if some of the shunts which the model refers to are set to None.
    • Transient Stability: fixed error in reporting of limit status and thus the reported state derivative of the pitch compensation for the WT3P model. Note it would still simulated correctly, it just wasn't reporting properly when it was at a limit.
    • Transient Stability: modified so SVC machine models allow stabilizers as a feedback.

September 23, 2014

Features and Improvements

  • Transient Stability: Added an additional "Other Field" for induction motors to report the presently used Device MVABase used internally by Simulator. This can change throughout the simulation by load relays or by models such as CMPLDW.
  • Bug Fixes

    • Transient Stability: Fixed error when modeling a motor in CMPLDW which had been 100% tripped. Three-phase motors (either the A, B, C, or D) which are 100% tripped can not be restarted so Simulator will simply open these motors and stop integrating them.

September 19, 2014

Features and Improvements

  • Power Flow Solution: Changed the way the 2-terminal DC line firing angle and tap control are handled when GammaMin = GammaMax. Under other situations once the maximum tap value is reached and the DC voltage is still above the desired setpoint, then Simulator will calculate a firing angle that exceeds GammaMax. This has been changed now so that if GammaMin=GammaMax, then the firing angle will remain constant and instead the DC voltage setpoint enforcement is abandoned and the DC voltage will be higher than the setpoint. When this occurs a prominently highlighted message will be written to the log. This change in control feature was added primarily to match the treatment in several ERAG/MMWG, PJM, and MISO cases we have seen recently which have some erroneous input data.
  • Transient Stability: modified the WT1G1, WT2G1, WT3G1, WT3G2, and WT4G1 wind turbine models so that they ignore any implicit step-up transformers.
  • Transient Stability: Modified reading of a GNET.idv file to allow multiple gnet sections in the same file to be read.
  • Transient Stability: added other field for CMPLDW to show the "Fraction not tripped on under voltage" for the Type 3 motors.
  • Bug Fixes

    • File Formats: When reading the hdbexport CSV files, modified reading of XF records so that if ID_XFMR values are not read at all then no three-winding transformers are created.
    • Transient Stability: Fixed a bug that was causing an access violation when auto inserting and deleting previous contingencies
    • Transient Stability: Treatment for handling low voltages for GEWTG was missing and was added.
    • Transient Stability: fixed error in the PSS3B stabilizer. Using this stabilizer was causing an error when running a transient stability simulation
    • Transient Stability: A bug was occurring when opening a generator which had a COMP or other voltage compensator model assigned to it
    • Transient Stability: fixed error in displaying data for IVOEX exciter in the case information displays. The Max/Min values were shown as blanks.
    • Transient Stability: When one of the blocks on either an IVOEX or EXIVO exciter were configured such that A2=0, A4=0 or A6=0, then the block becomes a PI controller. The initialization of the PI controller was not done properly and has now been fixed.
    • Transient Stability: fixed initialization of the CompCC model so that the order in which models are initialized does not prevent matter. CompCC is assigned to a generator record but then refers to a second generator. Previously the generator with the CompCC model had to be initialized BEFORE the second generator. The software now handles the ordering.
    • Transient Stability: Fixed error with using a wind turbine model with an implicit step-up transformer. The voltage measurement was not working properly and is now fixed.
    • Transient Stability: modified EXAC1 and EXAC1A to include subinterval integration when Ta=0 AND Tb=0.
    • Transient Stability: modified ESAC5A to include subinterval integration when Ka/Ta is large.
    • Transient Stability: fixed error in the use of the WT2E power slip curve.
    • Transient Stability: Fixed error that only occurred when tripping a portion of Motor A, B, C, or D if it was a double-cage motor model inside of a CMPLDW or CMPLDWNF model. Error was an improper calculation of derivative of the rotor speed.
    • Transient Stability: Modified handling of LD1PAC and thus CMPLDW at extremely low voltages (below 0.2 per unit) to better handle them in the algebraic network boundary solutions.
    • Transient Stability: Modified the handling of validation for very low Tppo values for the CMPLDW and CMPLDWNF model.
    • Transient Stability: When loading in a transient plot series from an AUX file which referred to a PlayIn signal the plot series was not created. This has been fixed.

September 3, 2014

Bug Fixes

  • Case Information Displays: On the Bus Case Information Display, the "Bus Neighbor List (in service only)" field was reporting all neighbors regardless of branch status. This has been fixed.
  • Contingency Analysis: When calculating a multi-section line contingency using the linear methods, the results would not properly account for islanded generation or load if the dummy buses contained generation or load. This has been fixed.
  • Transient Stability: Modified so that in order for an electrical island to be considered viable it must have at least one machine model which is modeled as a voltage source behind an impedance (such as a synchronous machine). Therefore, islands which are created during a simulation by a switching action that result in an electrical island that contains only Type 3 and 4 wind turbines (and other machines modeled as a constant current injection) are not considered by themselves to be enough to support an island.

August 25, 2014

Bug Fixes

  • Transient Stability: Modified the reactive current injection for type 3 and type 4 wind-turbine models so that for voltages below 0.4 per unit, the current injection will linearly fall to zero at 0.25 per unit voltage
  • Transient Stability: Fixed bug in WT3E and WT3E1 models. The Ipmax limiter on the power command output was not being enforced.

August 21, 2014

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Allow string expressions to be referenced by name in addition to location number.
  • Case Information Displays: Added a new field for BRANCH, GEN, and SHUNT objects called "RegBus by ObjectID". When showing this field, the option that is used to specify which key field to use in SUBDATA sections is used to identify the regulated bus by either primary, secondary, or label identifiers. When reading from an AUX file any of these identifiers can be used to identify the regulated bus.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed access violation that could appear when using the CTGSolve script command to solve a contingency while the case is in DC power flow mode.
    • General: Fixed an access violation that could result when using the MOVE command on a branch, the owner being used before the move is the default owner, and the from bus of the branch following the move is a different owner than the original default owner. Now if the branch has the default owner before the move we will force it to have the default owner after the move as well. The default owner is the owner of the from bus.
    • Transient Stability: Fixed error in reading the ZLIN1 model from a DYD file when nfar value is read as negative. This negative sign in the DYD file indicates the units of the r1ang1 and x1z1 values. Simulator encodes this distinction in the "Imp Type" flag instead. When nfar was read as negative value from DYD we were not properly setting the "Imp Type" flag.

August 19, 2014

Features and Improvements

  • Contingency Analysis Tool: Added options to open the Bus View or Substation View by right-clicking on a contingency violation.
  • Bug Fixes

    • Integrated Topology Processing (ITP): When using a full-topology case and using the equivalencing tool to delete the external system, an access violation could occur. This has been fixed.

August 13, 2014

Bug Fixes

  • Transient Stability: The CLOD load model has extra parameters Vi, Ti, and Tb to specify a load level at which load should be dropped. This feature was not disabled by default but it is now disabled by default.
  • Transient Stability: Fixed a one time step delay in propogation of Eppr and Eppi when using a single cage motor model with the MOTORW (or inside the CMPLDW and CMPLDWNF models) model.

August 6, 2014

Bug Fixes

  • General: Access violations could result if creating a bus through an auxiliary file or pasting from Excel without explicitly defining an owner. This has been fixed.
  • Transient Stability: Fixed an error with reading an auxiliary file that contained generator relay, LCFB1, PlayInRef, and under/over excitation.
  • Transient Stability: Modified the auto correction of the GENTPF and GENTPJ models for very low values of Xqpp. If (Xqpp = 0) or (Xqpp < 0.01*Xdpp), then we assume Xqpp is not known so we set Xqpp=Xdpp and thus remove all transient saliency. If Xqpp < 0.5*Xdpp then we set Xqpp=0.5*Xdpp. Xqpp and Xdpp should be very close to each other and values radically different cause numerical problems.
  • Transient Stability: Fixed error with initializing WT3E if WT3T model was omitted.
  • Transient Stability: Modify Vrmax or Vrmin of ESST1A exciter if necessary to initialize without limit violations.
  • Transient Stability: Fixed error with TSGetResults script command and TSGetContingencyResults SimAuto function. If results were requested for an open object, values for other objects would not show up in the results. Now only results for the open object will not be included.
  • Transient Stability: Fixed a bug with the PlayInRef model. At time 0 the value was not being changed from the initial value to the signal value specified at time 0.

July 23, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): The RenameFile script command will now allow special keywords (@DATETIME, @DATE, @TIME, @BUILDDATE, @VERSION, and @CASENAME) to be included in the new name of the file. The special keywords will be replaced with their actual value.
  • Integrated Topology Processing (ITP): When saving the consolidated case through the SaveConsolidatedCase script command, the contingencies were not being saved for the consolidated state. This has been fixed.

July 21, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug when saving the Injection Group records using SUBDATA section and specifying to identify by label. It was saving using Name_NomKV instead. The reading worked fine, but the saving of the AUX file was incorrect.
  • Transient Stability: When reading a DYD file and encountering MOTORW or CPMLDW records with a negative MVABase specified, Simulator was seeing the negative value and setting it to 0.0 instead. This has been fixed to correctly read the negative value which has special treatment for those two data records.
  • Transient Stability: Added message log warnings when reading a DYD file with faulty CMPLDW records that had extra parameters. Previously no warning message would appear with the CMPLDW records as appeared with other types of records. In addition, previously the first extra parameter in the CMPLDW records would overwrite the MVABase of the record. It has been fixed so that extra parameters are ignored and an appropriate warning message is written to the log. Most frequently these extra parameters indicate an error in the data file.
  • User Interface Dialogs: Fixed a bug on the Limit Monitoring Settings Dialog when saving the settings to an AUX file. It was not properly saving the Area and Zone object "Report Limits" field (YES/NO field). This was only true on this dialog.

July 17, 2014

Bug Fixes

  • Power Flow Solution: Fixed a very rare error in phase shifter switching which could occur if impedance correction tables had very large values AND you were simultaneously enforcing discrete phase shifter steps. It was possible for the phase shifters to become stuck in this situation because of some internal hueristics to handle impedance corrections with large values. This has been fixed.
  • Transient Stability: Modified the MOTORW model for double-cage motor simulations. Previously, PowerWorld had assumed that MOTORW model dynamic equations were treated the same as MOTOR1, CIM5, CIM6, and CIMW but with the simplification that saturation was ignored and that Xl = 0.8*Xdpp. Customer testing showed that the they were actually slightly different dynamic models which give different results. We have modified the MOTORW to use these special dynamic equations instead.
  • User Interface Dialogs: On the system equivalencing dialog, when choosing to Delete the external system, it was possible for an access violation to occur if a 3-winding transformer had a terminal bus set to be equivalenced but the internal star bus was not set to be equivalenced. This has been fixed.

July 16, 2014

Bug Fixes

  • Contingency Analysis: It was possible in the DC contingency analysis for an error to occur if the only generator in the entire case that could respond for MW make-up power was configured with MaxMW < MinMW. The error would cause Simulator to freeze. This has been fixed.
  • General: Fixed a problem when creating new buses with the area number specified to be 0. All buses need to be assigned to an area, and if none is specified, area number 1 should be the default. This wasn't happening correctly which would result in access violations when trying to view area information for a bus.
  • Transient Stability: Made a fix so that load relay models that monitor the rate of change of frequency will calculate this correctly. The input into the derivative block was always set at the initialization frequency of 60 Hz. This affects models DLSH and LSDT8.
  • Transient Stability: Fixed some caption hint strings for the CMPLDW and CMPLDWNF models
  • Transient Stability: Fixed bug in the calculate of R2 for the MOTORW model if it represented a subtransient motor model. This could cause the the initialization of the motor to be slightly off.
  • Transient Stability: Modified MOTORW (and thus CMPLDW and CMPLDWNF) reporting so that values like torque and power are reporting in actual MW units instead of per unit. The per unit values for these can be difficult to interpret because the MVABase for these model is calculated in the model.
  • Transient Stability: Fixed an error with the SimAuto command TSGetContingencyResults. It wasn't working and was starting from zero no matter the input time was not zero.
  • Transient Stability: Modified the LD1PAC model (and thus CMPLDW and CMPLDWNF) so that during load initialization a breakpoint between operating on the stall curve (impedance) and the "2" curve (defined by Kp2 and Np2). This breakpoint will be set equal to the smaller of either Vstall or the intersection of the two curves for the power curve. During algebraic solutions the P and Q algebraic equations will flip between the stall curve and the "2" curve at this calculated breakpoint. Thus even if the motor stall timer (TStall) has not expired, the algebraic model may still move to the stall curve for voltage values below this calculated breakpoint.

July 2, 2014

Bug Fixes

  • File Formats: Fixed access violation that would result if reading an Areva HDBexport file and the CBTYP records are missing.

July 1, 2014

Bug Fixes

  • File Formats: Memory leaks could result when reading in a large number of Areva HDBexport files in a single Simulator session. This has been fixed.
  • Integrated Topology Processing (ITP): There was a problem renumbering areas and zones when using the Equivalencing tool and Topology Processing. This has been fixed.
  • Integrated Topology Processing (ITP): For some cases, using Topology Processing will result in a "list index out of bounds error". This has been fixed.

June 26, 2014

Features and Improvements

  • Contingency Analysis Tool: Deleting a large number of contingencies (10,000s), but now ALL, was very slow. Delete All contingencies was fast and deleting a few was fast, but deleting a large number and not all was very slow. This is fixed.
  • Sensitivity Calculations: When calculating PTDF values added a new MWAtZero:1 field for an interface which is similar to MWAtZero, but it assumes each transfer direction containing an injection group is configured to represent an area and as a result the "net injection" of each injection group in the MWAtZero:1 calculation is assumed to be equal to the export of the most common area in the injection group.
  • Sensitivity Calculations: When opening the PTDF dialog, the type is automatically set to Multiple if any directions are defined.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Setting the variable name "EquivLineID" for the object Equiv_Options was not working properly
    • General: A "stack overflow error" could sometimes result when building a power system equivalent. This has been fixed.
    • Oneline Diagrams: Fixed an access violation that occurred when drawing an unlinked switched shunt symbol on a oneline
    • Sensitivity Calculations: Modified so that the Multiple Direction PTDF value fields for Branch and Interface objects are only available as a field/column if the Direction is marked as "Include = YES". This ensures that when using the script command SaveData with the variable "FGPTDFMult:ALL" or "LinePTDFMult:ALL" that fields are not included for directions that are skipped.
    • Sensitivity Calculations: Modified Interface field for showing MWAtZero for PTDF calculations to only include Directions marked as "Include = YES" in the calculation.
    • Transient Stability: Continuing to fix the treatment of single phase air conditioner models under extremely low voltages. This impacts CMPLDW, LD1PAC, and CMPLDWNF.

June 16, 2014

Features and Improvements

  • Available Transfer Capability (ATC) Tool: Added right-click option on the Transfer Limiters display to "Create Contingent Interface for Selection." This will create interfaces with a monitored branch being the Limiting Element in the Transfer Limiter and the contingent element in the interface being the Contingency Element of the Transfer Limiter.
  • Oneline Diagrams: A line will be drawn through a switched shunt display object if it is on continuous control or an SVC.
  • Transient Stability: Implemented LDELEC load model.
  • Bug Fixes

    • Power Flow Solution: A single bus system with both a generator and load should solve without giving the blackout message. Previously, a log message would indicate that the power flow solved but the blackout message would still appear.
    • Power Flow Solution: Angle smoothing is done when branches are closed to help power flow convergence. Some modifications were made to how this is done to further help convergence.
    • Transient Stability: User Defined Models have a function called "PropagateIgnoredStatesAndInput" that was not spelled correctly internally in Simulator causing the function to not be detected by Simulator when called from a DLL. This has been fixed.
    • Transient Stability: On the User Defined Model GUI, key fields for user defined model machine models were not getting populated correctly and an access violation could result. This has been fixed.

June 4, 2014

Features and Improvements

  • Contingency Analysis Tool: Added an option to auto-insert contingencies and name them by label.
  • Fault Analysis: Added an option to auto-insert faults and name them by label.
  • Oneline Diagrams: While in Run Mode, left clicking on a bus name or number field will open the Bus View for that bus.
  • Transient Stability: Added an option to auto-insert transient contingencies and name them by label.
  • Bug Fixes

    • Contingency Analysis: When using one of the linear solution techniques or when solving in dc power flow mode, the impact of contingencies that closed lines was not being correctly calculated. This has been fixed.
    • GIC: Fixed bug in which the line voltage was not set to zero if voltage was below the GIC cutoff value.
    • Transient Stability: Fixed a limit error in the undervoltage strategy of SVCs.
    • Transient Stability: Fixed some issues with the LD1PAC model, including implementing the Tstall time delay and using the correct MVA base for the heating calculations.
    • User Interface Dialogs: When using the equivalencing tool to save out a portion of the system to a PWB file, an error could result when appending the file to another case if transient stability data existed in the original system. Transient stability data is now currently not stored with the portion of the system saved to file.

May 29, 2014

Bug Fixes

  • Oneline Diagrams: Added drawing of automatic control symbol when drawing transformer symbol using circles.
  • Transient Stability: Reconnecting of motors after a voltage recovery was not working for the induction motors in the CMPLDW model. This has been fixed.
  • Transient Stability: When faulting induction motors inside CMPLDW model for an extremely long time (10s of cycles), the induction motor dynamics can result in numerical instability. Modified to ensure subinterval integration was properly used to prevent numerical instability.

May 28, 2014

Bug Fixes

  • Case Information Displays: Fixed access violation saving out substations to an aux file when the substation contains a dc line. Access violation might also occur simply opening the substation table.
  • GIC: Bug fix when going from transient stability to edit mode, deleting a bus, and back to transient stability there was an error on the GIC Gmatrix display.
  • Oneline Diagrams: The right-click local menu option for bus display objects to Insert Connected Buses and Then Auto Insert Lines, Gens, Loads and Shunts was not working. The buses would be inserted, but the other objects would not be. This has been fixed.
  • Power Flow Solution: Fixed errors with enforcing MVA and amp limits in VSC DC lines.
  • Power Flow Solution: When loading a case that was saved with island-based AGC on, the case might not solve even though it was solved when it was saved. This has been fixed.
  • Transient Stability: Fixed bug with the max and min of SVSMO2.
  • Transient Stability: There was a bug with the SVSMO3 model that was causing movement in steady state. This has been fixed.
  • Transient Stability: Fixed a problem with the SVSMO3 model when the power flow case has zero output because the limits are zero but the transient stability model does not have zero limits.
  • Transient Stability: For the SVSMO2 and SVSMO3 models, when Bmax and Bmin are zero this means that there are no limits. Previously, this was being treated as zero limits and setting the shunt to zero output.
  • Transient Stability: Adding handling of low voltage conditions to the IEEL model.
  • Transient Stability: Modified how the temperature was calculated for the A and B portions of LD1PAC. Previously we were missing the scalar multipliers from the calculation.
  • Transient Stability: Modified the order of terms in CMPLDW for Ftr1, Vtr1, Ttr1 to be Vtr1, Ttr1, then Ftr1 (same for the 2 values as well). This must have changed in the DYD file at some point.
  • Transient Stability: Modified scaling for induction motor percentage load drop.

May 7, 2014

Bug Fixes

  • Optimal Power Flow (OPF): Fixed bug calculating weighted marginal cost (by load and generator) for owner objects.

April 29, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed an error in the DirectionsAutoInsert() script command. It was sometimes possible to auto-insert a direction that had the same name as an existing direction (only if the Source/Sink pairs were different though).
  • Sensitivity Calculations: Fixed an error with calculating the MWAtZero value for an interface. It could sometimes show blank values incorrectly even when multi-direction PTDFs have been calculated.
  • Transient Stability: Fixed a bug with the PlayIn models. There was an access violation if the signal was -1. -1 means to not use the signal.

April 22, 2014

Bug Fixes

  • Case Information Displays: The Multi-section Line case information display would not allow use of Paste functionality. This has been fixed.
  • Transient Stability: A PWB file containing a PlayIn model could not be closed when exiting Simulator or loading a new case. This has been fixed. This bug was introduced in the March 19, 2014 patch.
  • Transient Stability: Updates were made to WT1G and WT2G default parameters.
  • Transient Stability: When clicking to insert a new type of model on the generator dialog, it is possible that there are no available models allowed. For example, for a WT1G (type 1) wind turbine then no exciter (electrical) model is allowed. Previously this would cause an "index out of range" error. It will now show a dialog indicating that "None available for this machine type".
  • Transient Stability: Added checking of Vbmax to the EXST3A model.
  • Transient Stability: In the Plot Designer portion of the transient stability dialog, when right-clicking on the list of plots and choosing "Generate Selected Plot", Simulator would not properly convert the @CtgName magic string into the name of the active contingency. This works when opening the plot in other ways, and it will now work via the right-click menu as well.
  • Transient Stability: Added ability to read the TIOCRS model from the DYD format.
  • Transient Stability: When showing transient stability model parameters in a case information display or when writing to an auxiliary file, Simulator will ALWAYS show 7 significant digits (excluding trailing zeros). Therefore, the user input for number of decimal places is always ignored.
  • Transient Stability: Fixed bug in TIOCRS model when used with a transformer on the "FROM" Bus. There was an error in converting the AMP pickup value which is now fixed. Would only matter for a transformer because the "CurrentBase" is different on each end of those branches.
  • User Interface Dialogs: Modified how the Initial Directory of the Open Case Dialog is handled when launching Simulator using a Short Cut and the Windows short cut setting for "Starts In". Simulator will now make sure that the first time the Open Case dialog is brought up it will start in the directory specified by "Starts In". Windows behavior changes in Windows Vista or Windows 7, so users switching from Windows XP will appreciate the behavior so it matches the behavior from Windows XP.
  • User Interface Dialogs: Fixed a bug that would not allow using the Enter key after editing a cell in a grid. This could cause dialogs containing grids to close instead of simply exiting the grid cell. This could also cause access violations.
  • User Interface Dialogs: Auxiliary File Export Description blocks allow specifying a special Use Selected filter. This was not working but has been fixed.
  • User Interface Dialogs: The Dynamic Formatting dialog now allows easier access to formatting any Object Type that is available in Simulator.

April 11, 2014

Bug Fixes

  • Contingency Analysis: Auto inserting shunt contingencies would not always work as expected. This has been fixed.
  • Contingency Analysis: Saving and loading auto insert settings for shunts did not work correctly. This has been fixed.
  • User Interface Dialogs: On certain Windows installations, the text in the Area dialog would not display correctly. The text has been changed and this should be fixed.

April 8, 2014

Features and Improvements

  • User Interface Dialogs: Added Ctrl+A and Ctrl+C functionality to the message lof to select all text and to copy the selection.
  • Bug Fixes

    • Case Information Displays: When listing Injection Group Participation Points by specific Point Types, the ID did not display correctly. This had been fixed.
    • Case Information Displays: Fixed the Time Step Simulation Area Custom Input grid so that pasting from Excel works correctly.
    • File Formats: Fixed memory leaks associated with reading the UCTE format.
    • File Formats: Fixed problem linking generators when loading the UCTE format.
    • Power Flow Solution: When using the Robust Solution Process and the solution fails, the "blackout" dialog will appear the same as it appears with other solution methods.
    • Security Constrained OPF (SCOPF) Tool: Fixed a bug that was causing D-FACTS to not get used for contingency violations.
    • Simulator Automation Server (SimAuto): When SimAuto is not registered with Windows, the message log will provide some instructions on how to register it.

April 4, 2014

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): When auto-inserting injection groups, if an injection group with the name already exists, previously Simulator would just leave the existing injection group alone and skip this for the auto-insert routine. This has been modified so that instead additional participation points are appended to the existing injection group.
  • Auxiliary Files (SCRIPT and DATA Sections): Added a messages to show the number of objects created when loading a AUX file data section.
  • Auxiliary Files (SCRIPT and DATA Sections): No longer keep the current directory and reset it after the OpenCase script command has been applied. We want the current directory to end up getting set to the directory in which the case is located.
  • File Formats: modified reading the hdbexport file so that if a UN record had (REG__ND <= 0) then the generator is placed to AVR=NO. We always set the regulated bus to the terminal bus if REG__ND <= 0, but now AVR will properly be set to YES as is intended by the file.
  • Sensitivity Calculations: added new MWAtZero field for Interfaces. When performing multiple direction PTDF calculations, this value shows the flow on the interface assuming all directions have their injection go to zero. This only works if the directions are defined as Area-Slack, Zone-Slack, or Injection Group-Slack. The value then takes the present MW of the interface and subtracts from it the PTDF*(Area/Zone Interchange) or PTDF*(Inj Group Total MW Injection) for each transfer direction.
  • User Interface Dialogs: When auto-inserting injection groups, if an injection group with the name already exists, previously Simulator would just leave the existing injection group alone and skip this for the auto-insert routine. This has been modified so that instead additional participation points are appended to the existing injection group.
  • User Interface Dialogs: The losses including series elements only will not display for lines or areas while in dc power flow mode. This had no meaning previously anyway, and was just confusing to show.
  • Bug Fixes

    • Case Information Displays: Changed the exception handling when determining if the clipboard has data in the correct format for pasting into a string grid. Could get random errors about not being able to open or access the clipboard that are irrelevant when they are produced. This seemed to occur because the string grid was being refreshed and not due to any actual obvious usage of the clipboard by Simulator.
    • Contingency Analysis: When loading from an AUX file contingency settings for the advanced limit monitoring settings, they were not being read properly. This has been fixed.

March 21, 2014

Bug Fixes

  • Contingency Analysis: The Contingency Records table in the Model Explorer would not allow customization of the displayed fields. This has been fixed.
  • Contingency Analysis: Fixed handling of Model Filters that should be disabled during a contingency because they are true in the contingency reference state and they are part of another Model Filter.
  • Power Flow Solution: Changing the transformer impedance correction table for a transformer using the Branch Information Dialog in Run Mode or deleting a transformer impedance correction table would not properly update the impedance for the transformer resulting in incorrect flows. This has been fixed.
  • Transient Stability: Modified PDCI model to automatically increase the ACVdclmax limit if the initial current exceeds this value. In practice values are frequently at 3100.6 amps in the base case, while the limit is 3100 amps.
  • User Interface Dialogs: A warning message will be sent to the Message Log when injection groups are not created while using the Auto Insert Injection Group tool because an injection group already exists with the same name.

March 19, 2014

Features and Improvements

  • Oneline Diagrams: On the right-click menu of a Bus Display Object, a new submenu item called "Then Auto Insert Lines to Directly Connected Buses" has been added under the "Insert Connected Buses" menu item. This will add lines only between the currently selected buses and any of its adjacent buses whether or not they already exist or have just been added.
  • Bug Fixes

    • Contingency Analysis: Corrected how the status of buses is determined during a linear contingency calculation when changing injection from injection groups.
    • File Formats: When reading in a UCTE file, added error checking when reading transformer regulation data to make sure that both transformer terminals are found in the case.
    • Oneline Diagrams: Changed opening of onelines saved prior to version 11 to have an appearance closely similar to the original.
    • Oneline Diagrams: Fixed the option "Insert Connected Buses --> Then Auto Insert Lines" found on the right-click menu of a Bus Display Object. Lines will now be inserted if the connected buses already exist and not just if they have been newly created.

March 12, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Identifying Expression variables in auxiliary files using names instead of location numbers was not working. This has been fixed.
  • Case Information Displays: Substations can be auto-inserted from the Substation Case Information Display. When auto-inserting based on the branch impedance values, an access violation would occur. This has been fixed.

March 10, 2014

Bug Fixes

  • Simulator Automation Server (SimAuto): SimAuto would not register correctly with the latest type library. This has been fixed.
  • Transient Stability: Modified DEGOV to report the external states and added one other field for the output from the delay.

March 7, 2014

Bug Fixes

  • Contingency Analysis: Fixed access violation that could occur when using the Apply Selected Contingency option.

March 6, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): When using the DetermineBranchesThatCreateIslands script command, the Number of Islanded Buses, Islanded Load, and Islanded Generation can now be returned through aux file and SimAuto commands.
  • Case Information Displays: When selecting a field to remove from a list of selected fields, now try to account for the fact that a pipe, |, character might be in a custom field name. If a pipe existed, the field could not be removed from the list of fields. This has been fixed.
  • Contingency Analysis: In situations where a contingency creates a new island, and there is a very large MW imbalance in the newly created island, the power flow could fail. This has been fixed.
  • Simulator Automation Server (SimAuto): When using the DetermineBranchesThatCreateIslands script command, the Number of Islanded Buses, Islanded Load, and Islanded Generation can now be returned through aux file and SimAuto commands.

February 27, 2014

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): The DetermineBranchesThatCreateIslands script command will now allow you to enter a blank for the filename. If the filename is blank, the selected field will be set for lines that create islands regardless of how you have that option set.
  • Contingency Analysis Tool: When saving the auto insert contingency options to an auxiliary file, any advanced filters used in the settings will also be saved to the aux file.
  • Simulator Automation Server (SimAuto): New OpenCaseType(FileName, FileType, Options) function. This function behaves the same way that the OpenCase script command works with FileType and Options being the same as those specified with the script command. The Options parameter is optional.
  • Bug Fixes

    • Case Information Displays: When editing a cell in any table, the cursor was not always appearing. This had been fixed.
    • Contingency Analysis: The status messages when contingencies are running will now show the number of contingency that is being processed based on all contingencies that are not set to Skip rather than all contingencies.
    • Contingency Analysis: The auto insert contingency options were not being correctly loaded from an auxiliary file. This has been fixed.
    • General: Modified InterfaceElement objects so that you can use the "Selected" field. This allows them to be used by AUX scripting.
    • Transient Stability: Modified when writing out a DYD file so that if the "mvabase" or "mwcap" values are zero then we just omit them from the output DYD file.
    • Transient Stability: For exciter model IEE5TA, when Trh was zero, the value for Vref was not initialized correctly. This has been fixed.
    • Transient Stability: Fixed issue with response of governor model GGOV3.
    • Transient Stability: Fixed a bug that would not correctly total the amount of generation or load that trips during a contingency and is not tripped due to a specific contingency action.
    • Transient Stability: Modified Generic Limit Monitors options to make it clearer that they are related to generator SPEED and not the bus frequency.

February 5, 2014

Features and Improvements

  • Contingency Analysis Tool: When auto-inserting two-winding transformer contingencies, now have options on how to treat two-winding transformers that are part of three-winding transformers. The options are to insert the individual two-winding transformers, insert only the three-winding transformer, or to ignore these transformers completely and insert nothing.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): The LogSave script command did not properly interpret the AppendFile parameter if there were quotes around the entry. This has been fixed.
    • Contingency Analysis: Do not allow the Solve Power Flow action to be used with global actions, post power flow solution actions, or contingency blocks.
    • Contingency Analysis: Solve Power Flow actions impose an order in which actions are applied. Groups of actions that are applied together are separated by Solve Power Flow actions. TOPOLOGYCHECK actions will ignore this order and be checked and applied as necessary with each group of actions. Any CHECK actions that are part of global actions will be checked and applied if necessary in the first group of actions. POSTCHECK actions will be checked and applied if necessary after all groups of actions have been applied.
    • Transient Stability: When two generators are at the same bus and are using line drop compensation, Simulator automatically sums the currents for the Vcomp calculation. There was a bug that if one generator did not have an exciter Simulator was still summing the currents. This has been fixed.

January 28, 2014

Features and Improvements

  • Contingency Analysis Tool: Added option to auto insert three-winding transformers.
  • Bug Fixes

    • Power Flow Solution: Angle smoothing is done at the start of the power flow solution to condition voltages across branches that have just been closed in. There were some instances when this was producing "zero determinant" errors. This has been fixed. If an error is encountered while trying to do the angle smoothing, this will be noted in the message log and only voltage estimates at buses between the buses specified for smoothing will be calculated.

January 24, 2014

Bug Fixes

  • Simulator Automation Server (SimAuto): The OpenCase function can now be used to open cases in the auxiliary file format. The files must be specified with the .AUX extension.
  • User Interface Dialogs: The Scale dialog did not allow the specification of objects to be scaled by entering the appropriate values in the edit boxes and hitting Enter. The act of clicking the Enter button would close the dialog instead. This has been fixed.
  • User Interface Dialogs: Multi-section lines are now included in the auxiliary files that are saved with removed and added elements from the Present Topological Differences From Base Case dialog.
  • User Interface Dialogs: The auxiliary files that are saved with removed elements from the Present Topological Differences From Base Case dialog could include "fake" generators that are internally associated with SVCs. These are indicated by an ID of "<0". This problem has been fixed and these generators should no longer appear in the file.

January 21, 2014

Features and Improvements

  • Transient Stability: Made the "MOTORX" model available for use in Simulator. It's a stripped down version of MOTORW use with CPMPLDW.
  • Bug Fixes

    • File Formats: Modifications made to read RAW files that had fields omitted in records that we previously assumed would be present.
    • General: A problem existed where the device in a Device Filter would not be returned in certain circumstances. This has been fixed.
    • Transient Stability: Added parameter error checking with CMPLDW and CMPLDWNF so that if (FmA + FmB + FmC + FmD + Fel) > 1.0 then we normalize the values so that their sum is zero.
    • Transient Stability: Modified the way in which CMPLDW models handle moving loads to the end of the feeder to fix bugs related to fixing the voltage at the load end bus to 0.95 or higher.
    • Transient Stability: Added the ability to right-click on a list of Load records and choose to "Create Composite Load Model" for the selection.
    • Transient Stability: When choosing to expand the composite load model into pieces in the power flow model, the LD1PAC model was not having the LFAdj value initialized to 0.0 as is done in CMPLDW and the MVABase value was not being initialized properly based on Lfm from CMPLDW. This has been fixed.
    • Transient Stability: Fixed the LD1PAC model (which is used inside the CPMLDW and CMPLDWNF models). Primary bug fixed was scaling of the Kp1, Kp2, Kq1, and Kq2 values. This was not correct so that the loads varied wildly around the initial condition.

January 14, 2014

Bug Fixes

  • File Formats: Fixed bug that would not properly set the "Flagged for Delete in EPC" flag for some switched shunts when loading an EPC file with the status flag set to -4.

January 13, 2014

Bug Fixes

  • Bus View and Substation View Onelines: Fixed an access violation when opening the bus view with a VSC DC line selected in the string grid.
  • File Formats: When reading an EPC file, if the Min/Max Mvar values in the Gen data table were read as 0.0 and 0.0, then Simulator was automatically setting the Mvar output of the generators to 0.0 MVar and turning the generator to AVR = NO. This was a mistake if the generator record was configured to use the reactive capability curve (Qtable). In that case, Simulator will now wait to check whether the generator Mvar is within limits until AFTER we read the Qtable information and properly initialize the Min/Max Mvar values for the generator
  • Power Flow Solution: Fixed an error with the Jacobian calculation for constant impedance or current loads if the load is OPEN. We were include the terms contributed by these voltage-dependent loads even if the load was OPEN. This typically wouldn't cause a problem but did in a case where a load of -125 ZMvar was encounters at a low voltage bus that would never support this.
  • Power Flow Solution: When FROM side of a vsc dc line was set to control power, the set point values were not being used to initialize the calculations, so they had no impact on the output. This has been fixed.

January 8, 2014

Bug Fixes

  • Contingency Analysis: When clicking on the Contingency Dialog to save an AUX file with all the contingency-related input data, Simulator would properly save the Custom Monitor objects, but it did not automatically save the Advanced Filters which are used by the Custom Monitors. Simulator will now save these Advanced filter definitions
  • Contingency Analysis: On the Contingency Analysis Dialog, under the Advanced Limit Monitoring options, the dialog could potentially incorrectly set the "Decrease in low bus voltage " value incorrectly. This has been fixed.

January 3, 2014

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command SetInterfaceLimitToMonitoredElementLimitSum(filtername) where the filtername is a filter that applies to interfaces that should be adjusted by the command.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Modified the ExportAreaSupplyCurves() script command so that when exporting areas which are not on OPF control, we will instead write a supply curve based on the Export Bid associated with any MW Transactions.

January 2, 2014

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug in ConditionVoltagePockets that would always indicate that the script failed.
  • Auxiliary Files (SCRIPT and DATA Sections): Fixed problem using special keywords @TIME, @DATETIME, etc. when specifying the name of a file to save via script. These special keywords were not translated.
  • Security Constrained OPF (SCOPF) Tool: SCOPF Contingency Violations (PWLPOPFCTGViol) were not supporting Expressions. This has been fixed so that expressions can now be used.
  • Transient Stability: Fixed the TSGetResults script command to actually return results. It was giving an error because changes made to create temporary plots for returning the results had a bug.

December 20, 2013

Features and Improvements

  • Transient Stability: Added ability to use the special string @CTGEvents in transient stability plot definition strings. This string will be replaced with a list strings showing the transient result event strings which are written to the message log during the simulation.
  • Bug Fixes

    • Transient Stability: Modified so that when running TSSolve or TSSolveAll from a script that we write the same messages to the LOG as we would when running simulator from the Transient Stability Dialog. Previously after August 2013 we were writing out very time-step as well which was repetitive.
    • Transient Stability: Modified so that the transient stability options which specify how to treat "Exciter Automatic Parameters" and "Machine Saturation for S12 < S10" are properly saved to an AUX file. Previously they could be set on the dialog and saved with the PWB file, but they were not saved to an AUX file.

December 19, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Replaced script command ConditionVoltagesOnRadialBuses added in the 12/9/13 patch with script command ConditionVoltagePockets(VoltageThreshold, AngleThreshold, Filter); This script command will cover the same situations as the previous script command in addition to other situations. It will identify pockets of buses bounded by branches that meet the condition that the absolute value of the voltage difference across the branch is greater than VoltageThreshold or the absolute value of the angle difference across the branch is greater than AngleThreshold and the branch meets the specified filter. The buses contained within these pockets will have their voltages estimated based on the assumption that the voltages at buses outside these pockets are good.
  • Auxiliary Files (SCRIPT and DATA Sections): Allow special keywords @DATETIME, @DATE, @TIME, @BUILDDATE, and @VERSION to be used as part of the filename for SaveDataUsingExportFormat, SaveData, SaveDataWithExtra, SaveObjectFields, and WriteToTextFile script commands. These special keywords will be replaced with their actual values when the file is saved.
  • Auxiliary Files (SCRIPT and DATA Sections): Added ability to write out the "REVERSE" bids for a StudyMWTransactions object. Previously you would only see the area-to-area MW bids from the lowest area number to the highest when saving out to an AUX file.
  • Auxiliary Files (SCRIPT and DATA Sections): Added script commands RenumberBuses, RenumberAreas, RenumberZones, and RenumberSubs, each with a parameter denoting the number of the Custom Integer field containing the new numbers.
  • Case Information Displays: Added a read only field "In Outage?" to various objects to indicate if the object is referenced by a current Scheduled Action.
  • Contingency Analysis Tool: Added new solution type RESERVE LIMITS to contingency results. If there is not enough make-up power and the slack needs to be used, this will appear in the Solved fields. Violations will still be recorded.
  • File Formats: Added ability to read in three-winding transformer records from the hdbexport CSV files using the XF record's ID_XFMR field.
  • Scheduled Actions: Added a read only field "In Outage?" to various objects to indicate if the object is referenced by a current Scheduled Action.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When renumbering multi-section lines using the BusRenumber SUBDATA section, a fatal error no longer results causing the termination of the aux file reading if an error occurs in the renumbering. The error is logged to the message log and the renumbering is not done for the multi-section line in which the error occurred.
    • Contingency Analysis: Fixed error in the auto-insert single switched shunt outage feature.
    • Oneline Diagrams: Fixed an access violation in KML import for the new MISO format that would occur if the "import unlinked objects" checkbox was unchecked. For unlinked objects if the box is checked, a new graphic object will be created and drawn. If the box is unchecked, unlinked objects will not be imported.
    • Transient Stability: Modified SVCWSC and VWSCC machine models to support remote voltage regulation.

December 9, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added script command ConditionVoltagesOnRadialBuses(VoltageThreshold, AngleThreshold, FilterName). The goal of this script command is to find groups of radial buses that may have bad initial voltage estimates and to get a better voltage estimate of these buses based on assuming that the voltages on buses outside of the radial group are good. These radial groups are determined by finding branches that would cause islands AND the voltage difference (absolute value) across the branch is greater than the VoltageThreshold in pu OR the angle difference (absolute value) across the branch is greater than the AngleThreshold in degrees, thus identifying parts of the system that have large voltage or angle differences. The FilterName is optional and determines which branches will be examined. If not specified all branches are considered.
  • Bug Fixes

    • Case Information Displays: In the generator table, clicking on the Fuel Type field should allow a dropdown that shows all of the fuel type options and allows changing them. This was not working if a generator status was Open. This has been fixed.
    • File Formats: Modified reading UCTE node records. If type = 2 or 3, a generator will be created regardless of other input. The automatically created generator will be set to operate at 0 MW and 0 Mvar.

December 3, 2013

Bug Fixes

  • Power Flow Solution: Improved Angle smoothing routines in some situations
  • Transient Stability: Made a correction in svsmo3 overvoltage limits.
  • Transient Stability: The Injection Group OPEN actions were not functioning properly when determining the amount of generation or load to trip. This has been fixed.
  • User Interface Dialogs: Allow advanced filtering to work on the calculated field case info.

November 25, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a special SUBDATA section "BusRenumber" to a multi-section line records which allows you renumber the dummy buses in the multi-section line by using the same format as for specifying the dummy points.
  • Auxiliary Files (SCRIPT and DATA Sections): Added script action CTGRelinkUnlinkedElements. This does exactly what they name implies.
  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command ExportAreaSupplyCurves("filename.csv", "User Defined String", NumPoints); The first parameter is the name of the CSV file to which results will be written. The second parameter is an optional parameter for specifying a user defined string written to each entry in the resulting CSV file. If the second parameter is omitted, then a blank will be assumed. The third parameter is optional and is related to converting a cubic cost model into a piece-wise linear model. If you omit the second parameter we assume 5.
    The output of the file will have 7 entries for each area for Fixed Gen MW, Fixed Load MW, Fixed Shunt MW, Losses MW, Variable Min MW, Variable Max MW, Variable Present MW, followed by a set of Bid MW/Price entries represents the supply curve for the variable MWs.
  • Contingency Analysis Tool: Added the ability on the Contingency Analysis Element dialog to choose a branch OPEN or CLOSE event by choosing a multi-section line.
  • Contingency Analysis Tool: Modified so that the OPF solution can be solved after each contingency is applied.
  • Oneline Diagrams: Added ability to import KML files in the format used by MISO. The lines will link to lines in the RAW file, if they exist. There are no substations in the RAW file, so it will create them (but they will be empty) if desired.
  • Power Flow Solution: Modified the flat start routine when applied to a system which contains many 30 degree phase shifts related to Delta-Wye transformer connections. The new flat start routine will set voltage angles in a manner that handles these phase shifts.
  • Transient Stability: Added ability in TSGetResults() script command to use a file type of "JSIS" which will write out desired results in a format used by the WECC JSIS group.
  • Transient Stability: Added ability in the Plot portion of the transient stability dialog to export the plot information to a text file of the format used in the TSGetResults() script command. Also added ability to export in the JSIS format in the same location.
  • Transient Stability: Modified captions and descriptions for fields showing min/max statistics for generator "Frequency" to instead say generator "speed". They are showing the electrical speed of the generator. Values will typically be close to nominal frequency (normally 60) for synchronous machines, but may be much higher or lower for asynchronous generators such as wind turbines.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed a minor error introduced on 9/30/13 which would cause Simulator to prompt about saving SUBDATA sections when it was not necessary to see this prompt.
    • Oneline Diagrams: Fixed value for showing the PTDF on an interface pie chart. Value shown was showing 100*Percent instead of Percent.
    • Optimal Power Flow (OPF): When an unenforceable limit was hit for the NEGATIVE end limit on a branch or interface, if the percentage of the limit enforcement was not 100%, the the slack cost calculation was incorrect. This would not effect the MW dispatch or prices in the calculation but only the post-processing reporting of a "slack cost"
    • Time Step Simulation: Periodic schedules were not working. They would only be applied to the actual times for which they were defined. This has been fixed.
    • Transient Stability: When writing the WT3E1 model to a DYR file, the circuit id of the interconnection transformer was always being written as a 0. This has been fixed.
    • Transient Stability: Minor modification to the GENTPF and GENTPJ models to include the speed effects in the stator voltage equations which couple the dynamic model to the network boundary equations.
    • Transient Stability: Minor modification to the GENTPJ model to remove the dependence of the saturation on the sign of the Id term.
    • User Interface Dialogs: Some minor bug fixed related to the D-FACTS devices.

November 12, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command InitializeGenMvarLimits. This initializes all generators in the case so that they are appropriately marked as being at Mvar limits or not. This could be useful if manually setting the Mvar output of generators or changing their limits.
  • General: When defining expressions for objects, a new option has been added to treat blank entries as zeros in the expression instead of treating the entire expression as invalid.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Sped up the loading of AXD files with a large number of objects.
    • Auxiliary Files (SCRIPT and DATA Sections): The October 23, 2013 patch introduced a special syntax to PROMPT for filenames in script commands that open or save to file. This option wasn't properly applied to all script commands. This should now work with most all script commands that have a filename as an input.
    • Contingency Analysis: The Define Shunt Filter button on the Auto Insert Contingencies dialog was not working to select a shunt filter. This has been fixed.
    • File Formats: Simulator would stop reading a RAW file if the voltage and angle of three winding transformer star buses were missing, or if the last field of a FACTS device record was missing. Fixed it by setting defaults for star bus voltage and angle if they were missing, and setting a default for the last field of a FACTS device record if it was missing.
    • General: Expressions for dc converters were not able to use custom and calculated fields. This has been fixed.
    • Optimal Power Flow (OPF): When running the OPF solution in difference flows mode, the calculation was not being done correctly with all values actually coming from the Present case. This has been fixed.
    • Optimal Power Flow (OPF): The option to specify the AGC method for superareas on OPF during the standalone power flow solution was not being used. It was always set to participation factor. This has been fixed.

October 31, 2013

Features and Improvements

  • Transient Stability: Added frequency depdendence to constant impedance load models.
  • Transient Stability: Added speed voltage to GENTPF machine model.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): CalculateTLR, CalculateLODF, CalculateFlowSense, and Fault script commands could result in an error if trying to identify a branch by label or busname_nomkV. This has been fixed.
    • File Formats: When writing out the gcd flag to an EPC file, we will always write out a 0 because we don't actually write out any of these devices.
    • File Formats: In the RAW file format, switched shunts that are regulating generator Mvar output have their regulated bus set to the bus of the generator that they are regulating. In Simulator, the switched shunt and the generator that it is regulating must have the same regulated bus. We now make the appropriate conversions when reading and writing a RAW file. When writing, the regulated bus of the switched shunt is set to the bus of the first generator that is set to regulate the same bus as the switched shunt. If more than one generator exists, a warning message is written to the log.
    • General: When searching for a Line Shunt, the comparison of the ID was not being done in a case-insensitive manner. This has been fixed.
    • General: It was possible that a "fake" generator could show up in the case if an SVC was changed to different switched shunt type and the case was saved. This has been fixed.
    • Help: An update to the Chrome browser made it impossible to view the help files locally. This has been fixed. To repair your local help files, run the full installation file.
    • Sensitivity Calculations: When using the LODF matrix calculation, an internal initialization process was being done for each line outage/closure studied. This only needed to be done once at the beginning of the process. This fix will speed up the LODF matrix calculation considerably.
    • Transient Stability: Modified the writing to a DYD file when a WSCC load model is assigned to a specific LOAD record. The BLWSCC model in the DYD format is for a BUS record, but we will still write such a record if we come across the WSCC assigned to a LOAD. If there are multiple loads at the bus this could make the load model slightly different in the DYD file, but if this occurs a warning will be written to the message log.

October 23, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Within all script commands related to opening or saving files, added a new ability to specify a filename of a special form that instructs PowerWorld to bring up the Open or Save dialog for the user to choose a file. This will not work when using the SimAuto Add-on. The special syntax of the file name is generally "". The entire string must start with . After the word PROMPT there may optionally be a space delimiter following by a special caption to be placed at the top of the file dialog that appears (this caption must be enclosed in single quotes). If the special caption is omitted then either Save or Open is assumed. After the special caption there may optionally be a list of File Types and extensions specified. This list must be enclosed in single quotes. The list itself is composed of a pipe-delimited string (|) with the first string representing the first file type, the second string representing the first file extension, the third string represent the second file type, the fourth string representing the second file extension and so on. If no File Types are specified then 'All Files (*.*)|*.*' is assumed. An example string might be

  • File Formats: Converted times for contingency actions in WECC switch files to cycles.
  • File Formats: The GE Voltage Checking Limit Min and Max fields for buses are now stored in PWB files.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Updated the error message for the MergeBuses script command. A cryptic error message was generated when the BUS identifier was omitted from the element argument of the script command.
    • Contingency Analysis: Fixed treatment of Custom Monitors when BOTH the "Only report violations..." checkboxes were checked. The names of the checkboxes have also been changed from "Never report..." to "Only report..."
    • General: When merging buses with attached generators, the owners were not getting set correctly. This could cause an access violation when the case was closed. This has been fixed.
    • Integrated Topology Processing (ITP): When using options that automatically close breakers to energize switched shunts or close generators, the breakers that are valid for closing are more accurately determined. The assumption is that breakers that are the closest to the devices should be the ones that are closed. Previously, any breakers that would energize the device would be closed even if the closest breakers were already closed.
    • Oneline Diagrams: When exporting a oneline diagram to a KML file with unlinked elements an access violation could occur. This has been fixed.
    • Power Flow Solution: Added check on Slow B Control for SVCs to make sure that the voltage range defined by SlowControlVLow and SlowControlVHigh is equal to or inside the range defined by VLow to VHigh specified with the SVC. If this happens the slow control voltage range is adjusted to be equal to the SVC voltage range and the sVC is disabled.
    • Power Flow Solution: Added an oscillation check for SVCs on slow B control. If the SVC goes outside of the Slow B control range for more than 3 iterations the SVC will be disabled.
    • Transient Stability: When you clicked the Show Selected Plot Data in Case Info button on the transient stability plotting page, the number of decimal points in the case info could not be changed. This has been fixed.
    • QV Curve Tool: Aborting a QV run might appear to get stuck in an infinite loop. This has been fixed and a QV run should abort much more quickly now.

October 10, 2013

Features and Improvements

  • Contingency Analysis Tool: Added ability to auto-insert single switched shunt outages
  • Contingency Analysis Tool: Enhanced the ability to auto insert based on the distance from a particular bus. Previously the measure of distance was always “Number of Nodes”, thus each branch was treated as having the same distance measure. We now allow X, Z, and Length as well. This allows integrated use of the features available from the ConnectionsDetermine Path Distances to Buses on the tools menu of Simulator
  • Fault Analysis: Cleaned up ability to auto insert fault analysis to match the power flow contingency auto insert.
  • Transient Stability: Added the ability to auto insert Transient Contingency definitions in a manner similar to what is done for Power Flow Contingencies. Presently there are 4 choices described in separate items.
  • Transient Stability: Added ability to auto insert contingencies representing single transmission line faults. PowerWorld will automatically add two contingencies that each have three events for each branch chosen. A fault occurs at a user-specified Event Time, and then two events of OpenFrom and OpenTo are applied after a user-specified Event Duration. The two contingencies only differ by the fault location. The user specifies a Fault Location in percentage (value between 0 and 50) and then two contingencies are created with that Fault Location and “100 – Fault Location”. If a Fault Location of 49.5 or higher is specified, then we just make one contingencies with a Fault Location of 50%.
  • Transient Stability: Added ability to auto insert contingencies representing single transformer faults. Works the same as for a transmission line, except that the two contingencies created apply a fault at the From Bus and To Bus directly.
  • Transient Stability: Added ability to auto insert contingencies representing a single bus fault. PowerWorld will automatically add one contingency that has two events for each bus chosen. A fault occurs at a user-specified Event Time, and the the bus is opened (all lines attached are opened) after a user-specified Event Duration.
  • Transient Stability: Added ability to auto insert contingencies representing a single generator outage. PowerWorld will automatically add one contingency that has one event for each generator chosen. The generator will open at a user-specified Event Time.

October 9, 2013

Bug Fixes

  • File Formats: Fixed an access violation that could occur when saving a case that contains no labels. This was a bug related to the new feature in the previous patch which greatly speeds up loading cases with a large number of labels.
  • User Interface Dialogs: On the Model Expression dialog, when clicking on one of the Define... buttons to change the model field used in the model expression, clicking Cancel on the dialog that appears caused the model field to be cleared out instead of simply left as presently set. This has been fixed.

October 8, 2013

Features and Improvements

  • Contingency Analysis Tool: Modified to allow auto-insert of contingencies based on nominal voltage level without requiring that an advanced filter be created.
  • File Formats: Greatly enhanced the speed of opening and closing cases (either PWB or AUX files) which make extensive use of Object Labels.
  • Bug Fixes

    • Case Information Displays: In some circumstances, calculated fields would not appear in the list of available fields for an object type. This has been fixed.
    • Power Flow Solution: Fixed potential infinite loop which would occur for an SVC on "slow B control" which is hitting its high or low voltage setpoint limit
    • Transient Stability: Modified the reading a DYD file so that if at the end of reading the file there are loads for which no static stability voltage-dependent load model is specified then a dialog will appear asking the user how to treat loads without stability models. If any load models exist prior to loading the DYD file, then this dialog will not appear.
    • Transient Stability: Modified writing out to a DYD file so that an order of precedence is maintained for WSCC-related load models. They will always be written in the order of WLWSCC, ALWSCC, ZLWSCC, BLWSCC (for buses) and then BLWSCC (for loads) now.
    • User Interface Dialogs: Fixed access violation which occurred when inserting a new bus. The bug was related to changes made in the last patch to ensure that enough significant digits are shown in the nominal kV edit box of the dialog to support buses with very low nominal voltage. Buses with nominal voltages such as 0.535 kV are becoming common due to the modeling of wind farms.

October 4, 2013

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed error with parsing a SCRIPT file when the word SCRIPT was on the same line of text as the open curly brace {

September 30, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): The Scale script command now allows specifying the new value or scale factor through a field with the object type to scale. To use this option, the [parameters] input should contain variablenames instead of numeric values. When using a field rather than value, the scaling will be done by individual object rather than the aggregation of all objects selected for scaling.
  • Contingency Analysis Tool: Do not count Aborted contingencies as unsolvable. They are treated as their own category when reporting the final status with the number of violations and unsolvable contingencies.
  • General: Injection groups now have their own set of options that define how they should be scaled. There is also an option that determines if these options should be used. When set to be used, appropriate injection group-specific options will be used instead of tool-specific options. Tools that now allow use of injection group-specific options are PV, ATC, Island-Based AGC, Injection Group Area Slack, Time Step Simulation, and Scaling.
  • User Interface Dialogs: The Scale tool now allows specifying the new value or scale factor through a field with the object type to scale. When using a field rather than value, the scaling will be done by individual object rather than the aggregation of all objects selected for scaling.
  • Bug Fixes

    • Oneline Diagrams: If you resized a bus object and then used the Undo tool (or ctrl-z) to undo the resizing, the anchored devices could move to incorrect locations. This has been fixed.
    • Transient Stability: Fixed error in TLIN1 model. It was not properly monitoring for under-frequency tripping and thus never operated for under frequency.

September 18, 2013

Features and Improvements

  • Contingency Analysis Tool: Global Actions that are skipped will no longer be reported in What Actually Occurred.
  • Bug Fixes

    • General: When using the name of an expression or calculated field instead of the location number in a variablename that is part of an advanced filter condition, the variablename could not always be correctly determined resulting in the condition not being evaluated correctly. This has been fixed.
    • General: When identifying an expression variablename using the name of the expression instead of the location number, the correct variablename was not being identified. This has been fixed.
    • Power Flow Solution: In some situations power flow divergence could result if switched shunts were set to control the Mvar output of generators. This has been fixed.

September 16, 2013

Bug Fixes

  • GIC: Fixed user-interface error with trying to show the GIC G-Matrix when the GIC Calculation has not yet been performed.
  • Optimal Power Flow (OPF): Fixed bug introduced in Sept 11, 2013 patch related to the "slack cost" fix from that date.

September 11, 2013

Features and Improvements

  • File Formats: Added support for reading NDLIM records from an hdbexport CSV file. Entries are read into a bus record's bus-specific limit monitoring settings allow there to be specific high/low voltage for particular nodes.
  • Transient Stability: Added special treatment for wind turbine models which specify a low voltage active current management as a piecewise linear function. It was possible for the network boundary solution to oscillate when the voltage solution was very near the corner points at Lvpnt0 and Lvpnt1. This will not happen now.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): When using the AUX file script command LoadAXD to open an AXD file into a oneline, if the specified oneline diagram did not exist, then an access violation occurred. This has been fixed so that instead if the oneline does exist we automatically create a new oneline and open the AXD into that.
    • File Formats: Fixed error when loading an Areva hdbexport CSV file if a blank line exists.
    • GIC: modified to allow Custom fields for TGICXFormer object. It will just pass through the value for the underlying Three-winding transformer object. It it doesn't have an underlying three-winding object, then it passes through the value for the High winding BRANCH object.
    • Optimal Power Flow (OPF): Modified the calculation of the "slack cost" and sum of MVA violations when monitoring an enforceable line MVA constraint is encoutered. The actual OPF solution (dispatch and prices) were correct, but the reported total slack cost and sum of MVA violations was not correct when unenforceable limits encountered.
    • Transient Stability: Corrected handling of the controller deadband (db) on LCFB1 model. When greater than db or less than -db we were not properly shifting the signal up or down by db.
    • Transient Stability: Modified to support the GENDCO model by treating it purely as a GENROU model. Presently Simulator does not yet implement any DC offset modeling.
    • Transient Stability: On plot, a hint appears instructing you how to zoom in or out on the chart. The hint has been corrected to instruct you to click and move RIGHT or LEFT to zoom in and out. Previously it said UP or DOWN which wasn't correct.
    • User Interface Dialogs: Added fix for GUI problem in the contingency analysis dialog. In DC mode the radio group to choose the solution method was completely disabled, which did not allow users to choose between "DC" and "DC with phase shifters". The fix was to only disable the ac solution button inside the radio group.

September 6, 2013

Features and Improvements

  • Available Transfer Capability (ATC) Tool: When using the iterated methods, new Iteratively Found strings (CTG_ABORTED_LINEAR, CTG_ABORTED_AFTER_LINEAR, CTG_ABORTED_IN_FULL, and CTG_ABORTED_ITERATED) are possible if a contingency fails to solve because an Abort action has been implemented.
  • Contingency Analysis Tool: Added contingency Abort action. If this action is implemented the contingency will immediately stop processing. No violations or Custom Monitors will be recorded. Contingency elements with this action type can only be saved in an auxiliary file and will not save in a PWB file until Simulator version 18.
  • PV and QV Curve (PVQV) Tool: 'Aborted Contingency' is a new PV critical reason if a contingency fails to solve because an Abort action has been implemented.
  • QV Curves: ABORTED will be reported in the QV overview results if a contingency fails to solve because an Abort action has been implemented.
  • Bug Fixes

    • GIC: Better support for GIC auxiliary files.
    • GIC: Changed defaults for auto transformers and configurations.
    • Power Flow Solution: Disable transformers that are controlling the same regulated bus as SVCs. This is to prevent potential conflicts with different control ranges.
    • Power Flow Solution: When an SVC is on Slow B Control, the control changes will stop if the change in voltage is too small. This will prevent a possible infinite loop due to the control changes not significantly affecting the voltage.
    • Transient Stability: Modified so that the "list of out of service models" is written in lower case characters in a GE DYD file. GE PSLF seems to require this in lower case or models are not taken out of service.
    • Transient Stability: When running Distributed Transient Analysis, plots can be generated on remote machines and pulled back to the main process.
    • Transient Stability: Added parameter checks on T1,T2,T3,T4 for the CBEST model to eliminate common factors in transfer function.

August 28, 2013

Features and Improvements

  • Contingency Analysis Tool: Improved the descriptions in the popup hints shown with options on the contingency analysis dialog.
  • Oneline Diagrams: Added more verbose error checking for GPU contouring to include error messages in the log.
  • Retriever: When loading ABB Spider files for network data and real-time data, Retriever will automatically generate subscriptions based on the names in the real-time data file.
  • Bug Fixes

    • Contingency Analysis: Modified the CTG_Options variable WhatActuallyOccurredContingencyDescription so that all values are specified through only one variable instead of two.
    • Distributed Computation: Corrected bug introduced in the 8/19/13 patch that does not properly reconcile the post-contingency auxiliary file when using distributed computing with contingency and ATC analysis. This caused distributed computing to fail with an unknown exception.
    • Distributed Computation: Fixed a problem with distributed contingency analysis. An invalid pointer operation error might occur causing distributed contingency analysis to fail.
    • General: Fixed errors in showing any Difference Flows field for any interface that contains an injection group.
    • General: Fixed errors in showing Difference Flows for Mvar flows on interfaces that contain generators, loads, or injection groups.
    • General: Fixed errors in showing Difference Flows for MVA flows on interfaces that contain multiple interface elements. It was taking the sum of the MVA difference instead of comparing the total MVA in the base case to the total in the present.
    • GIC: Improved the GIC Transformer Dialog to not show tertiary fields if there is no tertiary winding.
    • Transient Stability: Modified the validation of CSVGN1, CSVGN3, and CSVGN4 SVC models so that CBase must be approximately equal to the Gen Maximum Mvar output, and the Generator MVA Base must be equal to the (Max Mvar - Min Mvar).
    • Transient Stability: Modified the CSTATT model to validate T1, T2, T3, and T4 time constants. These represent controller values that should not be modified.

August 26, 2013

Bug Fixes

  • File Formats: Added fixes for WECC switch file bugs. (1) TG record expected quotes around the generator ID. Simulator will now handle this field with or without the quotes. (2) MBL record expected quotes around the action type. Simulator will now handle this field with or without the quotes. (3) FL record was not reading the clear faults section. Now an open from and open to action are created at the clearfrom and clearto times. (4) Contingencies of the same name are now detected. When a collision is detected the last read record is kept. (5) The combo box at the top of the TS contingency dialog is now updated correctly with all contingencies.
  • General: Fixed access violation that could occur when trying to delete a Model Expression that was using another Model Expression that had already been deleted. This would mostly occur when an entire case was being closed.
  • Optimal Power Flow (OPF): When enforcing angle constraints, a second LP solution might be required to bring the angles within tolerance even though the constraints should have been enforceable with the first solution. This might occur if both the system slack and generators were being moved to enforce the constraints. This has been fixed.
  • PV and QV Curve (PVQV) Tool: During a PV run Simulator tries to maintain the system slack bus so that it doesn't move from its original value. Slack error can accumulate over time due to the many power flow solutions performed as part of the PV run even if the slack remains within AGC tolerance on individual power flow solutions. This wasn't being handled correctly in some circumstances and the slack bus may have moved too far in the final result. This has been fixed.
  • Transient Stability: MOdified WT1T to have its own MVA Base on which values are specified.
  • Transient Stability: Added non-windup limit enforcement for Ki state in HYG3 model.
  • Transient Stability: An error existed where the results returned by the TSGetResults script command and TSGetContingencyResults SimAuto function were off by one timestep. This has been fixed.
  • Transient Stability: Default values were not correctly handled by the TSGetResults script command or the TSGetContingencyResults SimAuto function. This has been fixed.

August 19, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added a new script command: TSResultStorageSetAll(objecttype, YES/NO). The first parameter is the objecttype such as GEN, BUS, BRANCH, etc. You may also use ALL to signify to do this for all classes. The second parameter is a YES or a NO. Using this command will toggle all the “Save All” fields to YES/NO. It will also toggle all the “state” fields (such as exciter, machine, governor, etc.) to YES/NO.
  • Case Information Displays: The GE Ohmic Data Flag field for branches can now be viewed in branch case information displays.
  • File Formats: When writing out an EPC file and the GE Ohmic Data Flag field is 1, R and X will be written in ohms and B in microMhos.
  • User Interface Dialogs: Quick Filters can now be used on dialogs when choosing objects.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed some errors with the SendToExcel script command if the workbook that is being written to is open when the script command is executed.
    • Contingency Analysis: Fixed a bug where the Post-Contingency Auxiliary File name would be blanked out if the file could not be found when specified from an auxiliary file.
    • Contingency Analysis: Corrected a problem that would not allow a relative path to be specified when providing the location of the Post-Contingency Auxiliary File.
    • Power Flow Solution: The SVSMO2 SVC model will now only move during the power flow solution if its regulated value is outside its high/low range. Previously, it was being adjusted to hit the target voltage which was causing oscillations in the solution.
    • Transient Stability: PIDGOV was not propertly using the MWCap (MVABase) associated with the model. This has been fixed.
    • Transient Stability: Fixed error with enforcement of non-windup limits with HYGOVR models.
    • Transient Stability: Ensure that log messages are written to show that something is actually occurring when using script commands to run transient stability.
    • Transient Stability: Ensure user cannot interrupt transient stability run started from a script command.
    • Transient Stability: Fixed treatment of damping in MOTOR1 model.

August 1, 2013

Features and Improvements

  • Transient Stability: Implemented the w2301 velocity limit.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed bug with the DetermineBranchesThatCreateIslands script command that could result in an access violation when closing Simulator.
    • Transient Stability: Fixed interploation bus for the GENCLS_GE playback model.
    • Transient Stability: Fixed bus with the timestep in creating two bus equivalents.
    • Transient Stability: Fixed bug in W2301 governor in which fInvTv was being inverted twice (and hence not inverted!).
    • User Interface Dialogs: While in Edit mode and viewing the BUs Options dialog, 2 decimal places will now be shown for the nominal voltage. This corrects an error that could change the actual nominal voltage when it shouldn't be. As an example, 0.58 kV would be converted to 0.6 kV when the dialog was closed even if the user made no changes.
    • Retriever: Fixed bug setting values current that was causing retrieved aliases to not be shown when a value was retrieved with one data source, but defined with another.

July 31, 2013

Features and Improvements

  • Contingency Analysis Tool: Added the ability to specify a list of Categories with contingencies and Custom Monitors. Categories determine which custom monitors are active for a contingency. For a monitor if no categories are specified, the monitor will be active for all contingencies. For a contingency if no categories are specified, all monitors will be active for the contingency. Otherwise, a monitor will only be active for a contingency if it has at least on category that matches one of the contingency's categories.
  • Transient Stability: When loading the TSR file, only 20 log messages will be written regarding objects that are not in the present case.
  • Transient Stability: Added a message to the log when the minimum and maximum B values for switching and min and max continuous B values are switched for SVCs.
  • Transient Stability: Added the ability to specify a list of Categories with a Transient Contingency and Transient Limit Monitor. If no categories are specified for a limit monitor, the limit monitor will apply to all contingencies. If no categories are specified with a contingency, all limit monitors will apply to this contingency. Otherwise, a limit monitor will only be active for a contingency if it has at least one category that matches one of the contingency's categories.
  • Transient Stability: Added a local menu option on the list of transient contingencies called Time Shift Contingency Elements. This will allow you to time shift all contingency elements of selected contingencies by a specific amount of time in seconds.
  • Bug Fixes

    • Optimal Power Flow (OPF): When using DFACTS devices as part of the OPF solution, correct sensitivites were not being calculated resulting in DFACTS devices not being turned on when they should have been. This has been fixed.
    • Optimal Power Flow (OPF): Now correctly using the option specified with areas for allowing DFACTS control during the OPF solution. Previously, this option was being ignored.
    • Transient Stability: Fixed a divide by zero bug when the timestep is zero for the REX exciter model.
    • Transient Stability: When starting a transient at a negative time, the simulation will run correctly, but the case information displays showing the time in seconds may be off by a multiple of 60 seconds. This is purely a display error, but has been fixed.
    • Transient Stability: Biased the playback file frequency values so we interpret them correctly.

July 25, 2013

Bug Fixes

  • Contingency Analysis: When writing contingency records to an AUX file using the option to save all contingency related results and options to an auxiliary file, the custom memo, integers, floats, and strings were not being properly written to the AUX file. This error was introduced on the May 10, 2013 patch and has been fixed in this patch.
  • Contingency Analysis: Contingency Limit Violations were not properly showing the field for BUS voltage violations for Element IdentifierNum From or Name From. This error was introduced in the April 5, 2013 patch when adding similar features for transient contingency limit violations. It is fixed by this patch.
  • Power Flow Solution: Made changes to detect errors in continuous B and switching Bsh min/max values for SVC switched shunts. If the user input had these values flipped, a solution failure would occur. Simulator will now flip these min/max values if they are inconsistent.

July 17, 2013

Features and Improvements

  • GIC: Added handling of YDD transformers.
  • GIC: Replaced GIC transformer display with new unified display.
  • Bug Fixes

    • File Formats: Fixed bug writing out older versions of PSS/E SEQ files.
    • General: Fixed access violation that could occur when loading in a case containing three-winding transformers. This bug was introduced with the 7/15/13 patch.
    • GIC: Fixed access violation introduced with the 7/15/13 patch associated with automatically creating three winding transformers for use with GIC calculations. Generally corrected the creation of three winding transformers for use with GIC calculations.

July 15, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Added new script command CTGJoinActiveCTGs(InsertPowerFlow, DeleteExisting, JoinWithSelf, "filename"); that will join the current contingency list with itself or another list of contingencies contained in a file.
  • GIC: Added GIC transformer field to show if buses are in different substations.
  • Bug Fixes

    • File Formats: Fixed an error with writing out the "Control Type" for a transformer to an EPC file. When transformer control is disabled (XF Auto = NO) then Simulator should always be writing out a "1", but for LTC transformers we were writing out a "2". This has been fixed.
    • File Formats: Fixed error reading PTI format contingency files (*.con) if the circuit IDs of lines are enclosed in quotes.
    • Transient Stability: Updated exciter models EXAC1, EXAC1A, EXAC2, EXDC1 and ESDC1A to handle OEL1 hard limits.
    • User Interface Dialogs: Allow "Bus Shunt (Fixed)" control mode to be set when creating a switched shunt from the switched shunt dialog.
    • User Interface Dialogs: When specifying that a "Bus Shunt (Fixed)" switched shunt be controlled by an SVC on the switched shunt dialog, set the "Available for SVC Control" field to 1 to indicate that this shunt can be controlled. Previously, the fixed shunt was being assigned to the SVC but it was not set to be available for control.

July 10, 2013

Features and Improvements

  • GIC: Adding a dialog for specifying values for a GIC transformer dialog to make user entry easier.
  • Scheduled Actions: Added ability to use a "Scheduled Action" filter on a case information display showing a list of "Scheduled Action Groups".
  • Transient Stability: The switched shunt SVC power flow model has a Xc parameter. There dynamic model also has an Xc parameter. If these are different this will cause a problem when running a stability simulation. Validation will change the transient stability model to match the power flow model Xc.
  • Transient Stability: If a switched shunt model is NOT marked as an SVC in the power flow, but has an active transient stability SVC model (svsmo1, svsmo2, svsmo3), then this will be treated as a validation error and the stability run will not be allowed to run.
  • Transient Stability: Added a feature with induction motors (loads) and induction machine (generators) so that whenever the per unit speed drops below 0.1, then the entire integration time step will be reduced. A multiplier will be defined that is 0.05 at 0.0 per unit speed and increases linearly up to 1.0 at 0.1 per unit speed. The time step used by the integration will be equal to the user-specified time step multiplier by this value. If multiple motors/machines are operating in this region, then the smallest multiplier in the case will be used. This is intended to improve induction motor starting studies without the user having to manually reduce the time step for the entire simulation. It will be a very rare event when this occurs.
  • Bug Fixes

    • Integrated Topology Processing (ITP): When saving a full topology model out to a consolidated case and merging shunts into blocks, there was an error if the merged shunt ended up with more than 10 blocks. This has been fixed.
    • Transient Stability: When copying a plot and title block and not displaying the date and time, the date and time should not show up in the copy. This has been fixed.
    • Transient Stability: Fixed error in not properly setting up the C0 parameter for the CIM6 load model when initializing the load from the initial condition.
    • Transient Stability: When attempting to close in a synchronous generator during a transient stability run, an access violation was occurring. The problem was the synchronous machine should not be allowed to close in, so we have fixed to prevent this.
    • Transient Stability: Fixed error in passing the Pord signal from WT3E model to the WT3P model. Previously the WT3P model was always using Pelec as an input. This would only impact the results when the low voltage active power management was active such as when modeling faults very near the wind turbine terminal.
    • Transient Stability: Fixed error in the speed signal passed from the WT1T or WT3T model to the WT1P/WT3P pitch control (stabilizer). Previously we were passing the generator speed instead of the turbine speed. This would only impact turbines using the 2-mass model.
    • Transient Stability: The internally stored Bus field "Angle, No Shift" is always between +/-180 degrees. The Bus field "Angle" is then this value shifted by the reference angle. Because the original value "no shift" is shifted between +/- 180 degrees it only makes sense to the "shifted" value between +/- 180 degrees as well. It has been change to make this true.
    • Transient Stability: Fixed error with how svsmo1 and svsmo2 handle the control of discrete shunts.
    • Transient Stability: Fixed an event/log message generated by a LHVRT and LHFRT saying that a generator was being opened when the generator was already open. No error in simulation here, just invalid event/log message.

July 1, 2013

Features and Improvements

  • Contingency Analysis Tool: The contingency analysis Miscellanous option that specifies how to identify objects as a string in the results for "What Actually Occurred" could not be stored to an AUX file or set using a script command. This option is now available under the variablename WhatActuallyOccuredContingencyDescription:1 for the objectname CTG_Options.
  • Oneline Diagrams: Modified some size thresholds at which labels appear when exporting to the KML file.
  • Oneline Diagrams: Now when pressing Insert Connected Buses | Then Auto Insert Lines from a bus in a oneline the dialog will have an option to "Do this for all future edits". This will disable the dialog and will automatically do what you selected to automatically Re-size the Bus Size by Stub-size or interconnected lines to the bus every time you do Insert Connected Buses | Then Auto Insert Lines without asking again in the dialog.
  • Transient Stability: Added some error messaging when using TSGetResults script command with invalid syntax in the field specification. Previously if there was a syntax error Simulator would ignore the entire command but didn't indicate this to the user in an error message.
  • Transient Stability: Modified Type 3 and Type 4 wind turbine models to include hard-coded low voltage REACTIVE current management for per unit voltages below 0.3 per unit AC voltage. Starting at 0.3 per unit voltage, the reactive current will be reduced linearly from what the dynamic models specifies at down to zero at 0.1 per unit voltage. This is needed to allow extreme event modeling such as faulting at the terminal of a wind turbine or at a point that feeds wind turbines radially. A similar feature is part of the wind turbine models for ACTIVE current and starts at 0.8 per unit going to zero at 0.4 per unit typically.
  • User Interface Dialogs: Length edit box is disabled when viewing a transformer to prevent confusion because this means nothing for a transformer.
  • Bug Fixes

    • Case Information Displays: Corrected the specification of switched shunt mvar blocks when typing in a case information display. It wouldn't allow you to remove a block by entering 0 or blank.
    • Contingency Analysis: When using linearize DC approximations or the dc approximation power flow for contingency analysis, we do not store custom monitor violations. Previously we were storing them but they were always evaluated in the reference state which didn't make sense.
    • GIC: Modified GIC calculation to not treat transformers with delta windings as autotransformers regardless of the user input.
    • Oneline Diagrams: Now you can set the StubSpace even when the stubSize is zero. Before a dialog pop-up and didn't allow for a changed. This didn't make sense.
    • Oneline Diagrams: There was a bug when pressing Insert Connected Buses | Then Auto Insert Lines in the sense that if you added a bus and the interconnected buses were already in the oneline, simulator wasn't drawing the interconnected lines. Now it will draw the interconnected lines.
    • Power Flow Solution: An solution error would occur when using Difference Flows to view either the Difference or Base case, due to a bug in the calculation of SVC type switched shunts. This has been fixed.
    • Transient Stability: Fixed an error that would occur when editing a field of Sub Plot definition in the case information displays.

June 25, 2013

Features and Improvements

  • Transient Stability: Added new script command "TSAutoCorrect". This script command has no parameters. If there are still validation errors after running this script that would prevent the stability simulation from running, then the remainder of a script will be aborted
  • Transient Stability: Added log message warnings when parsing a TSR file to warn if objects in the TSR file do not exist in the present power flow case.
  • Bug Fixes

    • Transient Stability: When loading a TSR file into RAM, an access violation could occur if the objects in the TSR file do not exist in the case. This has been fixed.

June 24, 2013

Features and Improvements

  • Transient Stability: Added more stability data validation for the CIM5, CIM6, and CIMW motor models which specify induction motor parameters using the equivalent circuit R and X values. During Validation, Simulator will now calculate the Tp0 and Tpp0 parameters and check them against the integration time-step. If the resulting time constants are too fast, then appropriate validation messages will appear. When auto-correcting values, the R1 or R2 parameters may be reduced to increase the time constants.
  • Transient Stability: When validating stability data, we will now also validate models which are presently out-of-service, but can be closed in during the simulation. An example of this would be the induction motor models which include Generator Machine Models MOTOR1, CIMTR1, CIMTR2, etc., and Load Characteristic models CIM5 and CIM6.
  • Bug Fixes

    • Case Information Displays: Corrected an error from previous patch on June 20, 2013 related to showing the switched shunt blocks and steps when in Difference Mode.
    • Transient Stability: On the Transient Stability Dialog, when choosing Save All Settings ToSave Auxiliary Simulator writes out an AUX file containing all the various input and option settings on the transient stability dialog. This feature was not properly including all the Result Storage, Store to RAM options for the following object types: VSC DC Line, Multi-Terminal DC Record, Multi-Terminal DC Converter, Area, Zone, Interface, and Injection Group. This has been corrected.

June 20, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): The SendToExcel script command will now allow the saving of .xlsm filetype if using Excel 2007 or later.
  • Case Information Displays: When in Difference Flows mode, switched shunt Min Mvar, Max Mvar, Shunts Blocks, and Shunt Steps will now show differences between the Present and Base case.
  • Transient Stability: Added ability on a generator case info display to show and edit the transient stability input data for Rcomp and Xcomp (compensating impedance). This data can be specified on many different transient stability records. The Rcomp and Xcomp can be specified with special Other generator models (COMP, COMPCC, IEEEVC), with the generator machine models (GENROU, GENSAL, GENTPF, GENTPJ, etc.), or with some exciter models (the BPA type "F" exciters BPA_FA...BPA_FV). Values in the generator table are shown in the system MVA base, while the individual stability records may show them on the machine MVA base.
  • Bug Fixes

    • File Formats: Modified reading of sequence information from a PSS/E version 33 SEQ file so that entries after the first 15 can be omitted and a value of zero is assumed.
    • GIC: For three-winding transformers, ensure that the Medium winding is a higher voltage than Tertiary.
    • Transient Stability: Made some corrections when initializing SVC models SVSMO1, SVSMO2, and SVSMO3.
    • User Interface Dialogs: Updated the switched shunt dialogs to make the input of the SVC parameters clearer. The continuous element values are not used with SVSMO2 type SVCs.
    • User Interface Dialogs: When selecting the fixed shunts that can be controlled by SVCs, only switched shunts of type "Bus Shunt (fixed)" can be selected. The dialog that allows you to select this will now only show this type.

June 14, 2013

Features and Improvements

  • General: When using the tool to renumber multi-section line dummy buses, either through the GUI or script, a new bus that does not exist no longer needs to have a bus name specified. By default the bus name will be the same as the bus number.
  • Transient Stability: Added 7 new default curves for the TIOCRS overcurrent relay model.
  • Transient Stability: Modified to display a column in a case information display for a transient model showing you information if the stability model has all default data. For models for which there is only one set of defaults it will show "Default", while for other models such as TIOCRS, GEWTG, WNDTGE, EXWTGE, and EWTGFC it will show the name of the default data set.
  • Transient Stability: Modified the device dialog to show the name of the default data set if the model has all default parameters.
  • Bug Fixes

    • Optimal Power Flow (OPF): Modified the calculation of the "slack cost" when monitoring both positive and negative limits for an interface. The actual OPF solution (dispatch and prices) were correct, but the reported total slack cost was not correct when unenforceable interface limits which were violating their negative MW limit.
    • Transient Stability: Fixed oscillations that could occur in the SVSMO2 SVC model.

June 12, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Modified the CloseWithBreakers script command to allow input of a single object instead of a filter. The second parameter can now be the name of an advanced filter or the identifier for a single object of the objecttype that is specified as the first parameter. The single object identifier must be enclosed in square brackets and use the relevant key fields for the objecttype specified. The format for identifying a single object is the same as that used with the Move script command except that the objecttype should not be specified as part of the object identifier. Example: CloseWithBreakers(Gen, [1 "1"], YES);
  • Auxiliary Files (SCRIPT and DATA Sections): If loading in an auxiliary file with REMOVED object types, i.e. REMOVEDBUS, REMOVEDBRANCH, etc., the corresponding objects will be deleted in you are in Edit mode. REMOVED object types that are supported are any object that can be compared in the toplogical differences as part of the Difference Flows tool.
  • Auxiliary Files (SCRIPT and DATA Sections): Added script command DiffFlowRefresh that will reset the links between the Difference Flows Base case and the Present case. This should be used after a topology change has been made before any results are saved indicating elements that have been added or removed. It would especially be a good idea to use this before using the ContainedInDiffFlowsBC field to determine if an element has been added.
  • Case Information Displays: When using the option to display column headers as variable names, the upper left cell in case information displays will now show the objectname of the objects in the table.
  • Contingency Analysis Tool: Two new fields were added to the contingency summary that count how many GLOBAL and TRANSIENT actions were applied as part of the contingency.
  • Contingency Analysis Tool: Skipped actions will no longer show up as part of the What Actually Occurred summary for a contingency. This is to prevent cluttering the results when many Global Actions exist but are not applied during a particular contingency.
  • GIC: Added GIC fields to show the driving point resistance calculation at a substation. This helps in determining the sensitivity of the GIC currents to a change in the substation grounding resistance.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): The SendToExcel script command would result in an error if the workbook extension was not specified and the workbook existed. This has been fixed.
    • File Formats: When loading a RAW or EPC file, only mark a line with negative reactance as a series capacitor if the line has the same nominal voltages at each terminal.
    • File Formats: When loading in a PWB file, corrected lines marked as series capacitors if they do not have the same nominal voltage at each terminal.
    • File Formats: When appending an EPC file, update the regulated bus of a generator.
    • GIC: Fixed errors on the Unified Transformer display for showing the configuration at the High and Medium bus for two-winding transformers when the "From Bus" wsa not equal to the "High Bus".
    • GIC: Fixed error when using copy/paste or loading from an AUX file to update the GIC Unified Transformer data. This was not working properly for some three-winding transformers.
    • GIC: Fixed error on the Unified Transformer display with entering data for the winding resistances on a two-winding transformer when the "From Bus" was not equal to the "High Bus".
    • GIC: Simulator attempts to automatically determine the existence of three-winding transformers when the input data does specifically specify one by searching for buses connect to three transformers. This search algorithm has been modified so that it will not consider a grouping of three transformer a three-winding transformer if the potential start bus point has any generation or load connected to it.
    • Power Flow Solution: Fixed an access violation that could occur if the power flow failed to solve and there were SVCs of type SVSMO2 in the case.

June 4, 2013

Features and Improvements

  • Case Information Displays: Case Information object type is now available with Model Conditions and Custom Monitors.
  • GIC: On the unified GIC Transformer display, added the ability to High, Medium and Tertiary winding configurations and added ability to edit them from this display.
  • Oneline Diagrams: Added the ability for a Generic Model Field to show the "Case Information" object to show summary information about the entire case.
  • PV and QV Curve (PVQV) Tool: Added a new feature on the PV curve to specify an interface on which you desire to increase the MW flow. You then configure the OPF settings in Simulator appropriately and the PV Curve will move optimally move OPF controls (generator, loads, dc lines, etc.) to ramp up the loading on your interface
  • PV and QV Curve (PVQV) Tool: Added a new feature on the PV curve to specify 2 interfaces on which you desire to increase the MW flow and an angle (Angle of zero means increase only the first interface, Angle of 45 degrees means increase each interface equally, Angle of 90 degrees means increase only the second interface). Again the OPF controls must be configured appropriately.
  • PV and QV Curve (PVQV) Tool: Added a new feature on the PV curve to specify a third interface on which you additionally desire to maintain a constant MW flow.
  • PV and QV Curve (PVQV) Tool: Added a new feature on the PV curve to treat a negative dV/dQ value at a bus for which this quantity is tracked as a critical scenario (treated the same as a failed power flow solution)
  • Transient Stability: Modified the Transient Stability Generator and Load Summary case information displays so that the Paste option is available.
  • Transient Stability: Cleaned up the Unified GIC Transformer table features. Also added 3 separate fields to set the winding configuration on High, Medium and Tertiary winding.
  • Bug Fixes

    • Contingency Analysis: In the rare situation that a set of contingency actions cause a bus to become disconnected and then reconnected in the same contingency simulation, the reported values for Islanded Generation, Islanded Load, and Disconnected Buses could be incorrect. This has been fixed.
    • Fault Analysis: Fixed an error in fault analysis when load records existed which with a status of CLOSED, but a bus which was disconnected with a zero voltage.
    • Oneline Diagrams: When choosing to Autosave PWB files every so many minutes, and also setting it to "prompt" about whether to save the PWD files presently open, Simulator would prompt about the PWD files constantly. It will now simply not save the PWD files in this instance.
    • Power Flow Solution: Modified warning message in log when dispatching an island using an injection group when the injection group spans multiple islands. Simulator will not allow this type of control, but the warning message in the log was not properly communicating this.
    • Power Flow Solution: Cleaned up solution for Switched Shunt control for SVC Type 2 (svsmo2). This type of shunt control is now handled only in the voltage control loop similar to other traditional switched shunts instead of in the inner power flow loop as is done for svsmo1 and svsmo3.
    • Transient Stability: Fixed error in estimating the transformer configuration for Unknown configurations when the (From Bus NomkV < 100 kV) and (To Bus NomkV > 100 kV). These should be assigned as Delta - Grounded Wye, but were erroneously being set to GWye-Gwye.

May 28, 2013

Features and Improvements

  • Transient Stability: Generator "H (system base)" field is now enterable on generator tables. This edits the appropriate field for the corresponding active Machine Model. If there is no machine model or the machine model does not have interia, the field will be blank and nothing can be entered.
  • Bug Fixes

    • Transient Stability: Corrected issue in handling limits on PI blocks. This affects the ST4B, ST6B, and AC7B exciters.
    • Transient Stability: Corrected bug that allowed calculated Vfe limit to go negative. This affects ESAC2A, ESAC3A, ESAC7B, AC7B, ESAC8B, AC8B, EX2000, and BPA_FF.
    • Transient Stability: Archiving of TSR files was not working as a result of adding the saving of an AUX file with the TSR file. This has been fixed and the archiving of both the TSR files and AUX files is now working.
    • User Interface Dialogs: If the number of sections changes for a multi-section line, an added and removed element will both be displayed in Present Topological Differences from Base Case dialog. The comparison doesn't care how the dummy buses are numbered just how many there are of them.

May 21, 2013

Features and Improvements

  • Contingency Analysis Tool: Added support for using the transient shunt model MSC1 inside the power flow based contingency analysis processor.
  • File Formats: Saving a removed multi-section line in the EPC format should correctly write the sections of the multi-section line with a status of -4. GE flagged for delete flag for multi-section line will be true if any section is flagged for delete.
  • GIC: Added the ability to edit a special record called the Unitified Transformer in the GIC dialog. This record provides one place to edit all the GIC-related inputs for both two-winding and three-winding transformers so that you do not have to navigate through the internals of the three-winding transformer model or the various ambiguities introduced by auto-transformers. Also added copy/paste support from case information displays, and AUX file support for doing these edits.
  • GIC: The unified transformer refers to the terminolgy "high", "medium" and "tertiary" bus instead of primary/secondary/tertiary.
  • Help: Added more description of the Relay Zones and Overcurrent Curves to Line Relay help
  • PV and QV Curve (PVQV) Tool: Added option to open Bus View for an object associated with a data series on the PV plots the same as you could already do with the transient stability plots.
  • Transient Stability: For governor G2WSCC and GPWSCC, modified to allow BTurb*TTurb to be zero with both set to zero if their product is less than 4*local_MinDelt.
  • Transient Stability: For governor G2WSCC, added validation/error correction for field Td, Tt, Tf, and Tp to match what was already done for G2WSCC
  • Transient Stability: For the DISTR1 line relay model, added additional tripping messages so you still see "Entered Zone" result events when the delay is zero. Also added "Trip Initiated" result event for DISTR1.
  • Transient Stability: When reading in a DYD or DYR file, we now set the option regarding how to treat saturation functions for which the magnitude of SE1 and SE2 are backwards. This option is set to "Flip Values" when reading a PSSE DYR file to match that treatment. This option is set to "Ignore Saturation" when reading a PSLF DYD file to match that treatment.
  • Transient Stability: Modified DISTR1 so that it will base the GUI features of showing the "% reach" in columns and on the various relay zone pictures so that it will look through a series of branches that end in the TransferTripLine#1 as long as this creates an island (similar to the "farbus" specified with other relays)
  • Transient Stability: Modified TIOCRS so that the Threshold current is now specified in AMPS instead of per unit.
  • User Interface Dialogs: Added multi-section lines to the difference flows tool.
  • Bug Fixes

    • Contingency Analysis: When changing the name of a contingency make sure that the name is unique and prevent the change if a contingency with the same name already exists.
    • File Formats: When saving out all transient stability options from the transient stability dialog, the transient contingencies were not being saved with secondary key fields if the user selected this option. This has been fixed.
    • Oneline Diagrams: Fixed an error associated with the drawing of various gauge objects which made them difficult to click on with the mouse and also made them draw incorrectly
    • Oneline Diagrams: Added a bug fix so that background lines will blink with dynamic formatting
    • Power Flow Solution: When a switched shunt is controlling the Mvar output of generators, we added checks to see if generators are at a Mvar limit. If at a limit, the calculation of the switched shunt change now includes the amount of change need to to bring the generators off the limit.
    • Transient Stability: Simulator now properly uses the "Monitor" integer flag for DISTR1 so that we only monitor if "Monitor=0"

May 10, 2013

Features and Improvements

  • Oneline Diagrams: Changed the look of field arrows to be more discernible.
  • Oneline Diagrams: Added some features to translation files used when importing Areva/Allstom oneline diagrams. Also increased error reporting during import.
  • Bug Fixes

    • Contingency Analysis: Added some necessary fields when saving contingency and contingency element records to an aux file with default fields.

May 9, 2013

Features and Improvements

  • Case Information Displays: For Model conditions, modified the fields that identify the object used in the condition. Old Object File Format should be used with Simulator version 16 and earlier and version 17 prior to this patch. Object File Format uses a more friendly format that will identify the object by primary, secondary, or label key fields depending on the user's choice. Old Object File Format is able to load the object description in the old format that uses "" identifiers as well as the more friendly formats for primary, secondary, or label key fields, but it will write out in the old format for compatibility with older versions of Simulator.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: The linear ATC calculations were not always being correctly done when phase shifters are included. This has been fixed.
    • Contingency Analysis: Bus Limit Violation fields for the "From" Nominal Voltage, Area, Zone, and Substation were showing up as blank. They will now show the information for the bus itself.
    • Transient Stability: Added optional keywords LODREP and MODELS when writing out a DYD file. Also, added comments to DYD file to make it easier to read.
    • Transient Stability: Fixed bug related to deleting a Load Model Group. References from the load records to the load model group being deleted were not properly cleaned up resulting in an access violation.
    • Transient Stability: Additional fixes to prevent oscillations in the SVC models.

May 8, 2013

Features and Improvements

  • Oneline Diagrams: KML importer now has the ability to import KML files in the specific format that ERCOT uses.
  • Bug Fixes

    • Power Flow Solution: When trying to energize a dead island, an access violation could occur during the power flow solution due to the calculation that assigns voltages to the previously dead buses.
    • Retriever: Fixed eDNA retrievals.

May 2, 2013

Features and Improvements

  • Contingency Analysis Tool: Added a field with a contingency to report the total amount of generation drop that occurred during the contingency. This includes generation the is online in the reference state and become offline after the contingency for any reason. Reasons include islanded gen, gen opened from a gen or injection group action, and gen dropped from injection group merit order open action.
  • Contingency Analysis Tool: Created a new option for "Compare Contingency Definitions". This option will compare the presently defined contingency list against an AUX file (which contains another set of contingency definitions). The output will be a CSV file that lists contingencies that match one another. Note that this comparison only compares the actions in each contingency definitions. It does not compare the model criteria or actions status, thus it may report two contingencies as the "same" even though the conditional checks make them function slightly differently.
  • File Formats: When reading switched shunt records from a RAW file, a mode of 3 will now be interpreted as controlling the Mvar output of generation. Mode 4 and 5 to not correlate to features in Simulator, so these are treated as shunts with a constant Mvar.
  • Transient Stability: Increased a numerical tolerance for SVSMO1 and SVSMO3 to prevent a small numerical oscillation.
  • Bug Fixes

    • Contingency Analysis: Fixed how the nominal kV associated with a contingency violation is shown in the case information displays.
    • Transient Stability: Some line relay events where not identifying the associated line in the Events table. This has been fixed.
    • Transient Stability: Added initial limit violation check on Ilr for the TEXS exciter.
    • Transient Stability: Fixed incorrect reporting of the generator stabilizer output. The numerical simulation was using the correct stabilizer value, so the simulation was correct, but the output result reporting was showing the wrong values sometimes.
    • Transient Stability: Fixed TEXS exciter bug related to ignore the limit on the inputs of the PID controller (+/-Vimax)
    • Transient Stability: Fixed error in calculation of the "Zone Reach %" values for various line relays models which have a far bus specified.
    • User Interface Dialogs: On the switched shunt dialogs, when trying to set the regulation type to Generator Mvar, the dialog would instead set it to Custom Control. This has been fixed.

April 23, 2013

Bug Fixes

  • Available Transfer Capability (ATC) Tool: When using the ATCWriteToText script command to save a CSV file, the results could be in the wrong format if a contingency or limiting element name contained a comma. This has been fixed.
  • File Formats: When reading an EPC file, fixed a bug that could occur when loading SVD records that did not specify all fields. No obvious error would occur, but the data would not be loaded.
  • GIC: If a transformer configuration is not specified, a default value will be set.
  • Oneline Diagrams: There was a problem with Memo Text objects not showing all lines of text if a background fill was applied. This has been fixed.
  • Oneline Diagrams: There was a problem with Text objects not showing the background fill if the line thickness was greater than 0. This has been fixed.
  • Transient Stability: Fixed an interaction between non-windup limits and ignored states for governors.
  • User Interface Dialogs: When modifying the list of fields to include with an object type when defining an Auxiliary File Export Format Description, a list out of index bug could occur. This has been fixed.

April 18, 2013

Features and Improvements

  • Contingency Analysis Tool: Added more options to the Join Active Contingencies tool: (1) Join the active list to itself, (2) insert solve power flow action between contingencies that are being joined, and (3) delete existing contingencies.
  • General: The bus nominal voltage field now works with the Difference Flows features.
  • GIC: The Transformer Per Phase Effective GIC field now works with the Difference Flows features.
  • Bug Fixes

    • Bus View and Substation View Onelines: Fixed access violations that could occur when using a bus/substation view.
    • GIC: GIC script commands GICCalculate and GICTimeVaryingCalculate will now return error message if the power flow does not solve.
    • Transient Stability: Fixed an interaction between non-windup limits and ignored states for exciters.
    • User Interface Dialogs: Fixed error when showing the combo box list of string expressions at the top of the Expression dialog. It was showing the list of numeric expressions instead.

April 5, 2013

Features and Improvements

  • Case Information Displays: Added new branch fields which allow you to edit line limits in Amps instead of MVA. This only works for non-transformer branches. We only store one set of limit, so this only allows you to edit those limits in different units.
  • File Formats: When loading a RAW file, we now automatically flag any non-transformer branch with R=0, B=0, and X<0 as a series capacitor. This is especially important when using the Geomagnetically Induced Currents Add-on (GIC) as series caps will block the DC GIC flows.
  • Power Flow Solution: Added error checking for parallel transformers so that if they do not regulate the same bus (actually ZBR Bus group), then the transformer will be turned off control automatically and an appropriate message written to the log
  • Transient Stability: For Transient Stability Limit Monitor Violations, extra columns are now available to show the area, zone, owner, substation, nominal kV, labels, bus numbers, bus names, and circuits associated witht he respective violations. This is the same functionality as has always existed in the power flow contingency analysis tool.
  • User Interface Dialogs: Modified the list of recently open files so it will dynamically increase the visual width when file names become extremely long so that the entire file name can still be viewed.
  • Bug Fixes

    • File Formats: When loading an EPC file, changed the default setting of "Sharing of generator vars across groups of buses during remote regulation" so it default so use the SUM OF user-specified remote regulation percentages.
    • File Formats: When reading a RAW file, modified to handle bus records which omit the voltage magnitude and angle. If these values are omitted, then we assume a magnitude of 1.0 and an angle of 0.0. Previously it would cause an error when reading the file.
    • Help: Fixed a potential problem when invoking the Simulator help. Previously, an extra set of quotation marks were included in the URL passed to the browser which could cause a problem with some browsers. The user would see a strange %22 in the URL when this problem existed.
    • Oneline Diagrams: Fixed a possible error when loading the PWD file with Line Flows objects. The Theta angle was set wrong in some Line flows objects. This was causing the arrow to show the wrong direction from the line flow.
    • Transient Stability: Fixed bug in which the unlimited SEXS exciter output was being passed to machine models.
    • Transient Stability: Fixed limit checking on ignored states for IEET1A and IEEET2 exciters

April 1, 2013

Bug Fixes

  • File Formats: Fixed a bug that would not allow a RAW or EPC file to load. The message log would indicate that the file was loaded successfully, but no data at all was loaded.
  • File Formats: Modifications to better handle setting the voltage setpoint for generators and switched shunts when appending from an EPC file. The default setpoint for switched shunts is now 1.0 if a non-zero setpoint has not been specified.
  • Transient Stability: Corrected minor bug with line model LTC1 so now taps correctly go to their min/max values.
  • Transient Stability: Fixed a bug that prevented Gen Other Models from being made active once they had been turned off.

March 28, 2013

Bug Fixes

  • Power Flow Solution: Fixed a power flow convergence problem that could be caused by generators being taken off AVR control due to them oscillating by repeatedly hitting and backing off Mvar limits. This problem could occur if using the option to check generator Mvar limits immediately and the option to prevent controller oscillation.
  • Power Flow Solution: In a full-topology model while not using the option to use topology processing, the flows on breakers could be shown as zero. This didn't affect the power flow solution, just the displayed flows on breakers. This has been fixed.
  • Transient Stability: Updated the user interface for calculating V curves.
  • Transient Stability: Fixed a few problems with SVC models. The gain K/s at the PIO output of an SVC can be zero.

March 27, 2013

Bug Fixes

  • User Interface Dialogs: Fixed a problem with the patch on March 26, 2013 that could result in an access violation occurring when closing certain dialog boxes.

March 26, 2013

Features and Improvements

  • Transient Stability: Added LTC1 tap changing model for transformers.
  • Bug Fixes

    • General: Fixed a problem with licensing that could result in a 'Keyset does not exist' error and a broken licensing dialog box.

March 22, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Sped up reading of buses from auxiliary files.
  • Contingency Analysis Tool: Added a contingency-specific solution option to disable SVCs independently of other switched shunts.
  • Contingency Analysis Tool: Added options to include transient stability relay models, TIOCRS, LOCTI, and TIOCR1, as part of the power flow contingency solution. Models can act during the solution if their conditions are met. Transient models will be evaluated after POSTCHECK actions are implemented.
  • GIC: The layout of the GIC portion of the branch dialog has been updated.
  • GIC: Modified to show "GIC" in the Simulator status bar when GIC calculations are being included in the power flow.
  • GIC: Added a "Validate Input Data for GIC" button on the GIC dialog. Presently, this only checks if any lines are longer than 776.5 miles (1/4 wavelength).
  • Help: Added new SimAuto function GetSpecificFieldList
  • Help: Added new SimAuto function GetSpecificFieldMaxNum
  • Help: Added information on transient stability user defined models
  • Power Flow Solution: Added a power flow solution optin to disable SVCs independently of other switched shunts. The area option for shunt control only applies to non-SVCs. SVCs can only be enabled/disabled globally or at the individual device level.
  • Simulator Automation Server (SimAuto): Added two new SimAuto functions: GetSpecificFieldList and GetSpecificFieldMaxNum.
  • Bug Fixes

    • Bus View and Substation View Onelines: Removed options that are specific to the bus view (Layout Options, Number of Tiers, and Open Multiple Bus Views) from being stored as part of named Oneline Display Options when they are saved to the PWB file. These options are only stored in the registry now.
    • Contingency Analysis: Fixed an access violation that could occur when running contingency analysis. This would only occur if a case contained areas spanning multiple islands.
    • GIC: When using the option to clear the GIC results from the power system, the Effective Amps and Neutral Amps are also cleared on the transformer.
    • GIC: Cleaned up the interface for the GIC solution so that when "Include GIC in Power Flow" is not checked, it will NOT automatically include GIC in the power flow even if a value for transformer losses exists.
    • Power Flow Solution: A bug was introduced in the March 14, 2013 patch that affects the remote regulation of generators that are regulating buses within the same grouping of buses connected by very low impedance branches. This could lead to convergence problems with the power flow. This has been fixed.
    • Simulator Automation Server (SimAuto): Complex values were getting returned as integers when using any of the GetParameters functions. This has been fixed.
    • Transient Stability: When saving results to hard drive and the directory path does not exist, selecting Cancel on the dialog that prompts you that it doesn't exist will now prevent the simulation from running.
    • Transient Stability: When saving a PWB case with transient stability results after a bus or generator that had transient stability statistics was deleted, an access violation could occur. This has been fixed.
    • Transient Stability: Fixed an access violation that occurred when opening the transient stability dialog if a user defined load model had been saved with the case.
    • Transient Stability: Fixed bug associated with the display of the transient stability ybus when there are internal buses modeled with the transient stability models.
    • Transient Stability: Fixed an access violation when reading in user defined models from Excel.

March 14, 2013

Features and Improvements

  • Oneline Diagrams: Flow arrows based on Custom Float 1 will now work with the Difference Flows options showing Difference Case and Base Case.
  • Transient Stability: Added support for new overcurrent relay TIOCRS using standard curves. TIOCRS is identical in all respects to the TIOCR1 model, except for how the time to close is specified. TIOCRS allows the specification of curve parameters according to the IEEE C37.112-1996, IEC 255-4/British BS142, or IAC GE Curves standards.
  • User Interface Dialogs: When using the Difference Flows options for showing Difference Case and Base Case, Custom Float values will now be shown correctly in user dialogs.
  • Bug Fixes

    • Contingency Analysis: When determining which buses are remotely regulated by generators, Simulator considers buses that are connected by very low impedance branches to be the same. This will allow coordination of generator regulation among buses that effectively control the same bus. In certain situations, contingencies that cause the groupings of the low impedance branches to change could result in a generator not regulating the correct bus. This could lead to an incorrect power flow solution. This has been fixed.
    • Oneline Diagrams: The colormaps used for specifying various color parameters with the Geo Data Views were jumbled and did not look like colormaps. This has been fixed.
    • Oneline Diagrams: Line Flow Arrow objects could not always be properly selected. This has been fixed.

March 8, 2013

Bug Fixes

  • Optimal Power Flow (OPF): Fixed an access violation that could occur when opening the OPF Options and Results dialog after loading a case without first having selected Primal LP. This error would only occur if the case was saved with a previous OPF solution that included bus angle constraints.
  • Optimal Power Flow (OPF): Fixed an OPF solution error that could occur when including bus angle constraints.
  • Scheduled Actions: Changed the Scheduled Action dialog to apply an outage only when the View Time is strictly less than the outage End Time.

March 7, 2013

Bug Fixes

  • Bus View and Substation View Onelines: Fonts on bus views will scale is relation to the smaller screen dimension so that scaling remains consistent in portrait mode.
  • File Formats: Fixed some additional potential problems when loading SVCs from a PWB file that were not fixed with the Feb. 18, 2013 patch.
  • Retriever: Custom expressions are were not being saved saved to the Retriever aux file when they they are used in the monitors and alarms. This has been fixed so that custom expressions are now saved to the Retriever configuration aux file.
  • Retriever: There was a bug preventing users from deleting subscriptions in real-time mode. This has been fixed so that subscriptions can now be deleted in real-time mode.
  • Retriever: On the monitor string grid, the delete option is available but did not function in real-time mode. This has been fixed by disabling the delete option in real time mode.
  • Retriever: The monitors and alarms dialog had a problem that caused the sort and long description get reset whenever the create string expression button is clicked (or the resulting expression dialog is closed). This has been fixed so that the selected custom string expressions are persistent.
  • Retriever: The monitor, alarm, and severity level string grids have been updated so that newly created or removed alarms will cause the grids to refresh.

February 28, 2013

Bug Fixes

  • Oneline Diagrams: Fixed a problem that could cause Dynamic Formats saved with a oneline to not be assigned an Object Type. This could happen when loading a PWD file with dynamic formats already saved or loading an AXD file with dynamic formats.
  • User Interface Dialogs: Added better error checking and reporting of errors for Expressions.
  • User Interface Dialogs: Added a Test button on the Expressions dialog to validate the expression and help with expression design. After specifying the expression function, clicking this button will either provide the value of the result or an error message if the expression is not valid.

February 26, 2013

Bug Fixes

  • Contingency Analysis: When applying a generator Mvar contingency action to a bus, the Mvar output was not getting set correctly because the AVR status of the generators was not getting set to NO. This has been fixed.
  • Oneline Diagrams: Fixed a bug when copying and pasting oneline display objects along with their layers.
  • Oneline Diagrams: Fixed a bug where transmission line fields would jump around on the screen if moving the line to which they are anchored.
  • Transient Stability: Modified layout of the plot designer to prevent an access violation when switching to and from floating windows.
  • Transient Stability: Modified storage of Rotor Angle and Bus Angle to store a value of 0.0 if the bus or generator is not inservice.

February 21, 2013

Features and Improvements

  • Integrated Topology Processing (ITP): Added ability to monitor the flow on consolidated branches (Breakers, Disconnects, ZBRs, etc.) during contingency analysis.
  • Transient Stability: Added additional user interface features for ZPOTT, ZLIN1, ZDCB, and ZQLIN1 line relay models when the Far Bus is not the same as the To Bus. This shows the appropriate % coverage of the impedance relay based on the sum of series impedances between the From Bus and Far Bus. Previously it was only based on the impedance between the From and To Bus of the line relay.
  • Bug Fixes

    • Case Information Displays: Added a new field for transformers to show the Regulation Target Value. This is calculated from the Regulation Min and Max, the Target Type and the present voltage of the regulated bus.
    • Memory: Fixed some small memory leaks related to the storage of contingency definitions
    • Memory: Fixed a very large memory leak that occurred when using incremental topology processing in contingency analysis
    • Oneline Diagrams: Fixed a problem when reading in text fields from an AXD file related to whether the X/Y coordinate of the field represented the top-left corner or the center of the text. This was an old problem that had been fixed in version 16 last year.
    • Transient Stability: Fixed the setting of the far bus for the ZPOTT, ZLIN1, ZDCB, and ZQLIN1 line relays. This was not functioning so Far Bus could not be set.
    • Transient Stability: For the ZPOTT and ZDCB line relays, fixed the implementation the monitoring of the Other Relay at the Far Bus of the model. Previously it was always looking only at the To Bus end instead of the Far Bus.
    • User Interface Dialogs: Fixed bus when using the Find button on the Power Transfer Distribution Factor form to make behavior of the Find button consistent with setting the seller or buyer directly form the drop down box.

February 18, 2013

Features and Improvements

  • Simulator Automation Server (SimAuto): Fixed error in the SimAuto Command OpenCase() which was preventing the opening of EPC files
  • Bug Fixes

    • Contingency Analysis: Cleaned up the reading/writing to/from an AUX file of the various Advanced Limit Monitoring options associated with violations based on a change relative to the reference state.
    • File Formats: When reading in three-winding transformer records from a RAW file, we now allow a terminal bus to be specified which is NOT listed in the bus records if the STAT field indicates that the respective winding is OPEN. Thus the tertiary bus can be omitted from the bus table if the STAT=3, secondary if STAT=2, and primary if STAT=4. In these situations, Simulator will automatically create the bus number referenced as a terminal of the three-winding transformer and write an appropriate message to the log. Recent MISO cases were found to contain this structure for 145 transformers.
    • File Formats: Fixed potential error when loading a PWB file for a case which has multiple SVC models at the same bus
    • File Formats: Fixed some various errors when loading SVC models from an EPC file. For example when a bus of the SVC was presently disconnected. Also handled SVC types which are negative.

February 12, 2013

Features and Improvements

  • Contingency Analysis Tool: Added new contingency generator actions to Set To or Change By Mvar. When this action is used the generator will be turned off AVR. These types of actions are not saved in the version 17 PWB file because of compatibility issues. However, these action types can be saved in an auxiliary (AUX) file.
  • File Formats: Added file parser to read in EMS exported case as a text file from ABB EMS systems.
  • Oneline Diagrams: Added ability to link to a bus view or substation view from a Oneline Link. To use the feature, populate the File or Action string with the keyword BUSVIEW or SUBVIEW along with the number, name_kv, or label of the bus or substation that should open in the appropriate view.
  • Oneline Diagrams: Added option to resize buses based on the stub size when using the feature to automatically add lines when inserting connected buses. This option is found under Insert Connected Buses --> Then Auto Insert Lines... from the right-click menu of a bus while in Edit Mode. A dialog prompts the user about whether or not to automatically resize the buses. If user clicks NO, then it will resize the bus based on the number of incident lines. If the user clicks YES, the buses will be resized based on the stub size. This is the default and could, but could cause the buses to get excessively large.
  • Oneline Diagrams: Added ability to open bus or substation view onelines from oneline fields and other oneline objects. The bus view oneline will open to the bus that the device is connected to. The same ability has been added for the Quick Power Flow List.
  • PV and QV Curve (PVQV) Tool: Added ability to have plotting based on actual value, deviation, percent of the initial value, or percent deviation from the initial value.
  • Transient Stability: Added ability to have plotting based on actual value, deviation, percent of the initial value, or percent deviation from the initial value.
  • Transient Stability: Added new script command TSRunUntilSpecifiedTime(ContingencyName, [StopTime, StepSize, StepInCycles, ResetStartTime, NumberOfTimeStepsToDo]). The script command emulates what is done in the user interface. A time or number of steps may be specified and the transient stability will run until the specified time or for the specified number of time steps. StopTime should be entered in seconds. StepSize should be entered in either seconds or cycles depending on the StepInCycles field. StepInCycles should be YES if the stepsize is specified in cycles and NO if specified in seconds. ResetStartTime is either YES or NO and indicates if the simulation should be reset to the start time of the contingency. If the NumberOfTImesStepsToDo > 0 then only the specified number of time steps will be done regardless of the StopTime.
  • Bug Fixes

    • Bus View and Substation View Onelines: Fixed an error in when deleting the bus shown in the bus view. The bus view would not update properly and could produce an access violation. Now an empty view will be shown when the bus is deleted.
    • Sensitivity Calculations: Fixed an access violation that could occur if calculating TLRs for interfaces.
    • User Interface Dialogs: Fixed error that caused some toolbars to remain disabled when loading an AUX case.
    • Retriever: Fixed a bad default setting for the temporary retrieval directory. By default, the temporary retrieval directory was set to the same directory as the data file for a flat text data source. This was causing a locked files and failed retrievals when there are multiple Retriever clients accessing the data source over the network drive. The new default stored the temporary file on the local disk.

January 30, 2013

Features and Improvements

  • Case Information Displays: Added a field with generators, Mvar Capability Curve Is Defined, to indicate if the generator has a curve and not if the curve should be used. No longer create a default curve when setting the Use Mvar Capability Curve option to YES through the generator case information display and a curve does not already exist. A default curve will only be created if setting this option through the generator dialog and a curve does not already exist. A curve can only be used if one has been created and the option to use it is set.
  • GIC: Added ability to write G Matrix in Matlab sparse format.
  • Time Step Simulation: Added a button on the Results tab that will allow you to send all results to Excel. The format and data that gets sent will be the same as when sending each table to Excel one at a time. Only the results tables that actually have objects defined will be sent to Excel. All results will be sent to a new workbook in separate worksheets.
  • Transient Stability: Added the ability to create a V Curve for a generator. This can be done from the generator dialog on the Stability page, generator case information display, and through script command TSGetVCurveData. The curve will use the actual MW, Max MW, and Min MW with 50 points of Mvars between Min Mvar and Max Mvar for each of the MW points.
  • Transient Stability: Added script commant TSGetVCurveData("filename",filtername); where "filename" is the name of the file where the curves should be stored and filtername is a generator filter that specifies for which generators the curves should be created.
  • Bug Fixes

    • Available Transfer Capability (ATC) Tool: Allow other dialogs to be accessed when opening the Limit Monitoring and Violations dialog from the ATC dialog.
    • Bus View and Substation View Onelines: Fixed access violation that could occur if deleting the bus that is displayed on the Bus View.
    • File Formats: When appending switched shunt data from an EPC file and attempting to keep the IDs unique, instead of always modifying the Bus Shunt Fixed ID if there is a conflict, modify the ID of the shunt that is flagged for delete if there is one. The Bus Shunt Fixed will be modified if both shunts are flagged for delete. This is intended to set the ID of the shunt that shouldn't be deleted to the desired value if attempting to replace an SVD with a Bus Shunt Fixed or vice versa.
    • User Interface Dialogs: Updated the About dialog to allow users to reschedule or disable update checks without needing to actually run an update check.

January 18, 2013

Features and Improvements

  • Help: Contingency Element Status updates for TOPOLOGYCHECK
  • Transient Stability: Support new contingency types DB (delete bus), MBL (modify bus load), and RL (reinstate lines) in WECC switch files.
  • User Interface Dialogs: Updates to D-FACTS objects.
  • User Interface Dialogs: Edit boxes that have up/down arrows will automatically increase the number of digits to ensure that at least 2 significant digits are shown.
  • User Interface Dialogs: Added the ability to use dynamic formatting on any case information display.
  • User Interface Dialogs: Added the Type field to Scheduled Actions to indicate the type of outage: transmission, generator, or generator adjustment.
  • Bug Fixes

    • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug in the Scale script command that would not scale properly if scaling based on MW, Mvar.
    • Available Transfer Capability (ATC) Tool: When using a power flow case with multiple islands, OTDF values for branches not contained in the "main" island were not properly calculated. The "main" island is defined to be the one with the most buses. This has been fixed.
    • Contingency Analysis: TOPOLOGYCHECK actions will now be checked as part of the POSTCHECK solution if they have not already been applied. This will be done even if there are no POSTCHECK actions. They will also be checked again in the TOPOLOGYCHECK section if any POSTCHECK/TOPOLOGYCHECK actions are applied in the POSTCHECK section.
    • File Formats: When saving out a version 17 case in previous PWB formats, an error could occur when attempting to load the file in older versions of Simulator. This would occur if transient stability load model groups were defined and load characteristic models were assigned to the load model groups. This has been fixed.
    • Help: Specifying a path with spaces in it for the help file would not work. This has been fixed.
    • Power Flow Solution: Magnetizing conductance for transformers and conductance for lines were not properly being accounted for when solving the dc power flow using island based AGC with an injection group. This would cause the system slack to keep increasing by the amount of conductance. This was fixed by including conductance values as part of the shunt values reported for islands, areas, and the case when in dc power flow mode.
    • Sensitivity Calculations: Fixed a problem with TLR calculations when choosing the Slack as the transactor. Previously, the slack was determined from the island with the most buses. If the line or interface was not in the main island, no results were calculated. Now the slack is based on the island in which the line or interface is contained.
    • Transient Stability: When saving out a version 17 case in previous PWB formats, an error could occur when attempting to load the file in older versions of Simulator. This would occur if transient stability load model groups were defined and load characteristic models were assigned to the load model groups. This has been fixed.
    • Transient Stability: Removed logging of initial limit violation for GGOV1 regarding fsrt. This represents one of three inputs into a low value select block and it is not uncommon for the limit to be exceed in the steady state solution, thus logging the violation is unnecessary.

January 15, 2013

Bug Fixes

  • Auxiliary Files (SCRIPT and DATA Sections): Fixed a bug where some text fields would not be loaded correctly from a display auxiliary file.
  • File Formats: Fixed a bug where some text fields could not be generated correctly when loading Areva display files.
  • Oneline Diagrams: Fixed a bug where oneline fields that showed area to area tie line flows or zone to zone tie line flows were not showing the correct values.
  • Transient Stability: Fixed a bug where the specified options were not being used when using the dialog to create component objects in the power flow from the CMPLDW model.
  • User Interface Dialogs: The grids on the Scheduled Actions dialog were not allowing customizations to be saved. This has been fixed.
  • User Interface Dialogs: When setting the dc loss multiplier for an area or zone, the dc loss multiplier for buses within those groupings will be set to the same value regardless of where you change the multiplier for the area or zone. Previously, you could only change the multiplier from the special DC Power Flow Loss Setup dialog that contains the loss multipliers.

January 14, 2013

Features and Improvements

  • Auxiliary Files (SCRIPT and DATA Sections): Can now use the keyword ALL instead of using the location number of a field when specifying variablenames as part of a field list used with select script actions. This will return all fields with the same variablename. This is intended to allow easier access to fields when the exact number of fields is not known such as with multiple TLR (MultBusTLRSens:ALL) or PTDF (LinePTDFMult:ALL) results. This can be used with SaveData, SaveDataWithExtra, SaveObjectFields, and SendToExcel script actions.
  • Auxiliary Files (SCRIPT and DATA Sections): Can now use the keyword ALL instead of a variablename as part of a field list used with select script actions. This will return all fields for a particular objecttype. This can be used with SaveData, SaveDataWithExtra, SaveObjectFields, and SendToExcel script actions.
  • Simulator Automation Server (SimAuto): Can now use the keyword ALL instead of using the location number of a field when specifying variablenames as part of a field list used with select SimAuto functions. This will return all fields with the same variablename. This is intended to allow easier access to fields when the exact number of fields is not known such as with multiple TLR (MultBusTLRSens:ALL) or PTDF (LinePTDFMult:ALL) results. This can be used with SendToExcel and WriteAuxFile SimAuto functions.
  • Simulator Automation Server (SimAuto): Can now use the keyword ALL instead of a variablename as part of a field list used with select script actions. This will return all fields for a particular objecttype. This can be used with SendToExcel and WriteAuxFile SimAuto functions.
  • Transient Stability: Improved WECC switch file support.
  • Bug Fixes

    • Contingency Analysis: Fixed a bug that would not properly report interface violations when using one of the Advanced Limit Monitoring options that compares the violation results to base case conditions. This was only a problem when using one of the dc methods.
    • File Formats: An access violation could occur when loading a PWB file that contained a multi-terminal DC line as a tie line. This has been fixed.

January 11, 2013

Bug Fixes

  • Help: Fixed a problem with the original installation of Simulator 17 that would not set the default help location.
  • Transient Stability: Fixed the option to Create Composite Load Model that creates power flow objects from CMPLDW dynamics models when the models are assigned to loads through load model groups instead of directly assigned to load model groups.
  • Transient Stability: Fixed an access violation that could occur when loading a DYD file containing CMPLDW models in a case that doesn't have GE Long IDs assigned to the loads.