Development and Analysis of Applicability of a Hybrid Transient Simulation Platform Combining TSA and EMT Elements

This paper considers the use of hybrid simulation combining electromagnetic transients (EMT) simulation and transient stability (TSA) simulation to model large networks. By comparing with a full detailed EMT simulation, the paper shows that the hybrid approach gives more accurate results than TSA simulation alone, when power electronic equipment is included in the EMT part of the model. The paper also considers line switching and faults in the TSA part of the model which were ignored in earlier approaches, and shows that the accuracy is a function of the electrical distance of the fault to the interface bus bars. A new method to improve this accuracy with the use of switchable frequency dependent network equivalents (FDNE) is also introduced.