Application of a wide area backup protection expert system to prevent cascading outages

A strategy to prevent cascading outages in power systems is proposed in this paper. The strategy employs wide-area backup protection and artificial intelligence techniques to minimize the impact of a fault on a network. There are two ways in which wide-area backup protection can prevent cascading trips leading to a wide spread blackout: (1) precise location of a fault so that only the circuit breakers necessary to isolate the fault are tripped, and (2) avoidance of unnecessary trips, due to hidden failure or overloading, by blocking the trip signals of conventional backup protection relays. The limitations of conventional backup protection are examined and methods of improvement are presented.