Transient Stability Data from External files

Menus within the File menu
Bottom of the specific model pane on the Transient Stability portion of the Model Explorer,
Options within Stability Case Info Menu,
Buttons at the bottom of the Transient Stability Dialog.

Save to Auxiliary

in the will prompt for a filename in which to save an auxiliary file. Use this option to store any results and settings that need to be retained for future use or use with different power flow cases. Transient stability-specific results and option settings can optionally be saved with the PowerWorld binary file (*.pwb).

Load Auxiliary

Clicking this button will open a dialog to allow the user to select an auxiliary file to load. This is intended to be used for loading any relevant option settings to be used during the transient stability analysis. The dialog will be updated according to the option settings loaded from the file.

Save GE DYD Data, Save GE DYD Data with Options, Save PTI DYR Data, Save BPA SWI Data

Choosing this option will allow you to save models to the appropriate file format. Note that only models which are supported by the specific format will be saved to the file. For a list of which models are supported by which format see the Model Support Status case information display. When saving a DYD file, the model names are always stored lower case. When saving a DYR file, a GNET *.idv and a BASEGEN *.dat are also saved. The filename and path used are the same as for the DYR file, except "_GNET" and "_BASEGEN" are appended to the file names. Selecting "Save GE DYD Data with Options" allows the options to save data of only records modified in difference case, add a bus filter and sort generators, loads and switched shunts.

Load GE DYD Data, Load PTI DYR Data, Load BPA SWI Data

Choosing this option will allow you to load models from the GE DYD file format. Selecting the option "DYR Data with Options" will allow you to specify a MCRE *.rwm file to split up generators, a MTRLD *.dat file to split up motors, a GNET *.idv file to disable generator models, and a BASEGEN *.dat file to specify the Governor Response Limits flag for generators. "Load Specific PTI DYR Helper Files" allows you to apply those files on their own.
When loading from a GE DYD file a few special features have been implemented.

Load WECC Switch Data

Choosing this option will allow you to load transient contingencies in the WECC file format used with WECC switching processors. These files generally have a *.swt extension and describe the switching action desired and the time at which it occurs.

GE DYD: Special Handling for the Generator Baseload Flag

When loading GE EPC files, a flag exists in the EPC file with each generator record called the "Baseload flag". This field determines how governor limits are handled during a transient stability run. This feature is supported using Simulator generator field called Transient Stability\Governor Response Limits . For more information see the Transient Stability Overview: Generator Models topic.

GE DYD: Special Handling of EPCMOD models

In many example DYD files which PowerWorld has encountered, there are EPCMOD records which represents a user-defined model htat represent a Series Capacitor Relay and a Capacitor Relay Model. Because these models were so common, PowerWorld added two new kinds of relays to our model suite. The CAPRELAY model can be assigned to a switched shunt record. This represents a relay which can open and close a switched shunt based on a definite time relay measuring voltage. A SERIESCAPRELAY model can be assigned to a branch and used to bypass and place back inservice a series capacitor branch.

When parsing the DYD file, Simulator will detect an EPCMOD record and if that record refers to the EPCL program "MSC01.p", then we automatically assume it represents a switched shunt relay and create a CAPRELAY model. An appropriate log message will be written indicating this has occurred such as the following: "Info: An EPCMOD record using "MSC01.P" was found. Simulator will attempt to read following as a CAPRELAY: 30.000 1.2000".

When parsing the DYD file, Simulator will detect an EPCMOD record and if that record refers to the EPCL program "MSC02_R1.p", then we automatically assume it represents a series cap relay and create a SERIESCAPRELAY model. An appropriate log message will be written indicating this has occurred.

GE DYD: Special Handling of GENCC models

In the DYD often represent cross-compound generators in a special manner. A cross-compound generator represents two generators which both operate off the same steam plant. In a DYD file a cross-compound plant will be represented by 2 machine models, 2 exciters, 2 stabilizers, and 1 governor. In DYD files, the governor will be either the IEEEG1 or CRCMGV governors. Ideally, the power flow model represented by the EPC file will model these two generators explicitly and thus the DYD file will refer to the two generators when specifying the machines, exciters, stabilizer and governor. The DYD file however also supports a special machine model called the GENCC which is really just a GENTPF model but it signals to the tool reading the DYD file that two generators in the DYD file may represent one generator in the EPC file.

To accommodate this situation, Simulator's DYD parser has been written to first go through the entire DYD file and look for any bus which has only one generator in the existing case (EPC file), but the DYD file has 2 GENCC records at the bus with IDs that do NOT match any existing generator. If this situation is found, the user will be asked whether they would like to automatically split the existing generator into two generators to accommodate this modeling. If you choose yes, then the case will be permanently modified to split the generators into two. An appropriate log message will be written indicating this has occurred such as the following: "Info: New generator created at ALAMT3 G (24003) #L and existing generator ID changed to #H because 2 GENCC records found for Bus ALAMT3 G (24003) with IDs "H" and "L", but only one generator exists in the case at this bus with id "3"."

Also note that the GENCC records in the DYD file have parameters Pfac and Qfac which determine the percentage of MW and Mvar assigned to each generator. When the generators are split into 2 units, the following fields are multiplied by appropriate normalized Pfac and Qfac values: MW output, Max MW, Min MW, Mvar output, Max Mvar, and Min Mvar. The MVABase will also be multiplied but only if the GENCC record did not include this as part of its definition (normally it is included in the DYD file).

GE DYD or PTI DYR Data: Special Handling of Saturation Functions (SE)

When reading in a DYD or DYR file, there is an 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.

GE DYD: Read DYD file containing devices identified by label.

GE DYD: Reading of the AMETA record from a DYD file to indicate storage of angle information to transient stability results.

GE DYD: When the IFMON record is encountered all our options regarding storing results to include the MW and Mvar flows on interfaces are modified.

GE DYD: A check at the end of reading a DYD file to determine if there are loads which do not have any static/algebraic stability models assigned to them. If this is the case, then messages are written to the log notifying the user that all loads that do not have static load models will default to a "Constant Current P, Impedance Q". Also checking is done to see if there are ALWSCC models assigned to some areas but not others, and if this is the case then log messages are written to notify the user that some areas do not have ALWSCC models and list those areas.

GE DYC: Appending changes

When loading files with the extension ".dyc", the contents are automatically appended to the existing models.