Transient Stability: User Defined Models

See Also

 

User Defined Models (UDMs) are transient stability models that can be shared between users and programs. Each UDM is a dynamic link library (DLL) which contains code for implementing the model. The UDM process is the following:

• Engineers design a model.
• A developer writes a DLL for the model, creating the functions needed by the calling application (Simulator). The model is a black box to the calling application.  The inner details of the DLL are completely separate code.
• Users of the DLL have instances of the model in their case. The user's interaction with this model is the same as with in-built models.

Simulator can call DLLs developed in languages including C++, Fortran, and Pascal using standard calling conventions. Other calling applications may use the same DLLs. The UDM DLLs necessarily have a well-defined interface with the transient stability software. It is critical that the user defined model developer adhere exactly to the specifications of this interface. Details of this interface are documented in PowerWorld's User Defined Model Development Guide for those seeking a more in-depth understanding of model interactions. Contact PowerWorld Corporation at support@powerworld.com for more information.

 

User Defined Model data is managed on the Options: User Defined Models tab of the Transient Stability Analysis dialog. User defined models are supported for the following types of objects.

 

Generator-Related Models

• Machines
• Exciters
• Governors
• Stabilizers

Load-Related Models

• Load Characteristics

Multi-Terminal DC Record - Related Models

• Record Level Model (outputs a current setpoint to each DC converter)
• Multi-Terminal DC Converters (outputs a cosine of the firing angle at each converter)