Features and Improvements
- Transient Stability: Added support to read and write from a PSLF dyd and PSSE dyr file for Transient Stability models OEL2C and UEL2C.
- Transient Stability: Added support to read and write from a PSLF dyd file for Transient Stability models ESAC1C (AC1C in PW) and ESAC2C (AC2C in PW).
- File Formats: Modified loading of Areva hdbexport files in several cosmetic ways as follows
1. For LN2, XF2, ZBR2 records we were loading in RMEAS and WMEAS values into CustomFloat entries of the resulting Branch record in PowerWorld Simulator. This has been modified so that if entries are not found (values are blank) then we leave the custom float values as blank to indiciate they were unspecified. Previously they would come in as 0.000 instead. Also modified the order to that CustomFloat:0 = WMEAS; CustomFloat:1 = ZWMEAS; CustomFloat:2 = RMEAS; CustomFloat:3 = ZRMEAS.
2. Added the ability to include a KVMEAS value with each BS record in the CSV file. This value is then populated on every bus (ND record) created for this BS record as CustomFloat:0. If KVMEAS is blank then the CustomFloat:0 value remains blank.
3. When loading UN and LD objects the WMEAS and RMEAS are populated as CustomFloat:0 and CustomFloat:1. Previously if WMEAS and RMEAS were empty, then a value of 0.000 was assigned. This has been changed so that the values remain blank if they are not specified.
4. When loading LD objects the values for I_LDAREA, PARFRACW, and PF are used to create InjectionGroup objects in PowerWorld appropriate for performing load scaling in your case in a manner consistent with what is done in the EMS. This remains, however we have now also added extra custom values to the Load objects in PowerWorld to give you another way to see this information. CustomFloat:2=PARFRACW; CustomFloat:3=PF; CustomString:0=I_LDAREA.ID; CustomString:1=LDTY.
5. Reading of MONGRP objects in the CSV file resulted in the creation of PowerWorld LimitSet objects. Previously we had the prefix M_ on all LimitSet names. This prefix has been removed.
6. When reading ND records if the associated MNL record (from either ND, KV or CO record) has I_VLIM=0, then PowerWorld was always assigning the Bus to the Default LimitSet so that it would not be monitored. This was functionally fine because it meant that the voltage limits were not used (they were being set to Vlow=0.0000 and Vhigh=2.0000), however the user lost the assignment of the bus to a LimitSet. We now assign the LimitSet based on the MNL records I_MONGRP, however the Bus will be set to Monitor=NO.
7. When loading in LNLIM, XFLIM, and ZBLIM records, if the I__MNL=0 we now set PowerWorld's branch field Monitor=NO. Previously, these branches were assigned to the default limit group which was not monitored so the software function is not changed, but setting Monitor=NO made it more clear that no monitoring of that branch is done.
8. When loading an INTRFC record, if I__MNL=0 we now set PowerWorld's Interface field Monitor=NO. Previously, these branches were assigned to the default limit group which was not monitored so the software function is not changed, but setting Monitor=NO made it more clear that no monitoring of that branch is done.
9. When loading CP records, if the REG__ND=0 the shunt is now always set to ShuntMode=Fixed. Previously the AutoControl was being set to NO, but the ShuntMode may remain as Discrete. This doesn't change software function but makes it more clear what was intended in the hdbexport format.
10. When loading XF records from and hdbexport file the RegTargetType for branches is now always set to "Max/Min".
11. When loading in XF records, if the REG__ND=0 the branch ControlType is always set to Fixed now. The VTARGET associated with these records were always blank, so we were setting AutoControl=NO regardless, but this makes it more clear the transformer has no control.
- General: When tapping a transmission line, the owner of the new bus is now set to the owner of the near bus of the line being tapped. The owners of the new lines are set to the owners of the line being tapped. Previously the owners were not being set for the new bus and new lines, which could result in access violations.
- Power Flow Solution: PowerWorld keeps track of when the creation (and removal) of electrical islands are needed as branches are opened and closed. We will dynamically add or remove island slack buses to accommodate the new islands. When doing this dynamically, for an island to be considered viable, we require it to have at least some online generation and some online load. As a result some checks are needed when opening and closing generators or loads as well. Those were being done appropriately to make an island dead if all generation or load was opened, however there were some situations when closing in a generator or load to a presently dead island for which PowerWorld did not automatically choose a new slack bus and energize the island. This has been fixed so that in these situations a new energized island created.
- Transient Stability: The Q/P ratio reference input for REEC_A/B/C/D models can now be changed by using the setting the exciter setpoint during a dynamic simulation.