Features and Improvements
- Fault Analysis: Added faulted bus nominal voltage to the multiple fault results table
- File Formats: When reading a RAW file, PowerWorld parses the comments at the end of object records to create a label for the object. We look for the a string inside brackets , while skipping over spaces, forward slashes and astericks. This has been modified to also skip over comma characters when looking for the special brackets.
- Transient Stability: Added PSS7C Stabilizer.
- User Interface Dialogs: Modified the Generator Information dialog so that if the check-box "Use Capability Curve" is checked then the Min Mvar and Max Mvar edit boxes can not be edited. This is the same treatment as those fields on the case information displays which do not allow editing of those fields if they are calculated from the capability curves.
- Contingency Analysis: Fixed a bug that would make the Merit Order injection group contingency action behave like Merit Order Open when attempting to reduce the generator output in the injection group.
- File Formats: Fixed a very obscure bug when loading in three-winding transformers from an EPC file if the Maximum or Minimum tap ratio (tmax or tmin) were equal to exactly 0 (zero). Obviously the user doesn't care much about this since 0.0 doesn't make much sense, but when it was zero AND when there was a fixed tap ratio specified on the primary that was not 1.000 (tapfp <> 1.0), then Simulator was reading the tmax and tmin and shifting them by (1 - tapfp). Thus you'd see minimum and maximum tap values go from 0.000 to something like 0.025 or -0.025.
- File Formats: In both the EPC and RAW file formats, transformers records have a "type" integer indicating what type of control it is performing. These map to either Fixed, LTC, Mvar, or Phase shifting transformer in PowerWorld. PowerWorld also has a separate field called "AutoControl" which can be set to YES or NO to indicate if the transformer is actually performing any control. In the EPC and RAW file formats however, the user must specify that the transformer is "Fixed" in order to turn it off control. We have improved the reading of EPC and RAW files so that if a transformer is marked with the integer type indicating it is "Fixed", we will evaluate the following logic.
1. ( (ABS(TapMax) > 2) OR (ABS(TapMin) > 2) )
2. Transformer connect two buses with the same Nominal Voltage
If both of those are true, the we will read this as a phase-shifting transformer and set our AutoControl flag to NO.