Fault current limiter allocation in electric ship power systems

Due to increased levels of generation and large capacity and low impedance power distribution network, fault current level has become a serious problem in electric ship power system planning and operations. The utilization of fault current limiters (FCLs) in power system provides an effective way to suppress fault currents and results in considerable saving in the investment of high capacity circuit breakers. To enhance system security and improve protection system design in electric ships, an active FCL is proposed in this paper to suppress fault currents. A formula to determine smallest active FCL impedance required for fault current reduction under circuit breakers' interrupting ratings is derived by using an impedance matrix modify method. Performance of the proposed method is ensured using a practical electric ship power system. Effect of the locations for FCL installation on fault currents is also illustrated.