Incorporation of FACTS into transients programs for system simulation

Flexible AC transmission systems (FACTS) concepts rely on a rapidly controlled response to system disturbances. Accurate transient models of the device, the power system in the vicinity and FACTS controls become crucial for system studies. System studies must deploy models which extend beyond the immediate confines of the FACTS device. In other words, the requirement for detailed transient modeling has to be reconciled with large systems studies. The authors address transient modeling in the context of emerging FACTS applications. They concentrate on the problem of modeling for larger nonlinear disturbances rather than linearized small-signal analysis. Prior to the studies of performance, the FACTS control designer requires a platform for development and testing. Therefore, both the utility and the manufacturer have an interest in adequate modeling tools. Simulation techniques and developments to integrate different analysis programs are reviewed. In addition, work at the University of Waterloo, to incorporate real-time control constraints into programs for transient simulation, is outlined and supported by examples of computed responses to system disturbances