Application of real-time power system simulators for testing protective relay system operational characteristics

Proper protective relay operation is essential for power system reliability. System transient conditions and instrument transformer errors are major causes for relay misoperation. Therefore, relays tests need to include both transient simulation and instrument transformer models. This paper presents two techniques for protective system testing: real-time power system simulator (RTPSS) and playback system. Both systems can simulate transient testing as well as instrument transformers.