An AGC implementation for system islanding and restoration conditions

An island AGC function has been implemented in a large-scale power system, Virginia Power Company (VP), to assist in system emergency and restoration situations. It is the first time that the conventional AGC function has been enhanced to be utilized, rather than to be suspended, under such circumstances. The island AGC function is designed to be implemented in both the real-time and the dispatcher training simulator (DTS) environments. The latter provides a realistic closed-loop simulation environment that mimics the real system behavior, offering an excellent opportunity for operators to be well-trained, aware and prepared for abnormal situations. This implementation has been tested on the VP system model, which consists of 4400 buses and 775 generators. It has successfully completed custom factory tests, and it is the user´s opinion that the island AGC will provide a valuable additional capability for use during system restoration