Optimal bus splitting for short-circuit current limitation in metropolitan area

Transmission system expansion may cause excessive short circuit currents with respect to circuit breakers' limitation. This paper presents the method for short-circuit current limitation in the transmission system using bus splitting. Genetic algorithm and particle swarm optimization are used to find the optimal location and the number of buses to be split. The constraints are short-circuit current limit, voltage limit, generator limit and transmission lines limits. The method has been tested on the Electricity Generating Authority of Thailand (EGAT) metropolitan area power system. Test result shows that bus splitting can limit the short-circuit currents and the proposed methods, particle swarm optimization and genetic algorithm, can find the optimal location and the number of buses splitting. In order to find the global solution, the particle swarm optimization provides higher efficiency than the genetic algorithm.