Genetic Algorithm Based Method for Contingency Screening in Power Systems

Abstract

This paper proposes an application of Genetic Algorithm (GA) to contingency screening in power systems. The contingency selected by the GA bused screening method is the double line outage which has the risk of causing transient instability. Generally, the contingency screening problem including multiple outage can be interpreted as the combinatorial optimization one for searching the combination of single outages which makes the system insecure. Therefore, GA which is one of the probabilistic search for combinatorial problems, is applicable for such contingency screening problem. In the GA based contingency screening method, a double line outage is represented as a chromosome. The fitness of chromosome for environment is defined by using transient energy function of power systems. The new procedure for avoiding the loss of important outage during contingency screening is developed and embedded in the proposed method by using the theorem of schema for GA. The validity of the proposed method is confirmed by applying to 6-machine 30-bus 40-line system. The result shows that the GA based contingency screening has the potential for practical use.