Semiconductor fault-current limiters. Part 1: Problems connected with and possible schemes for implementing short-circuit current limitation in power systems

Power systems are interconnected to improve system reliability, stability and economy of operation. Because of the large capacity of interconnected systems, the currents fed into faults assume enormous levels. Hence, the need for fault-current limiters (FCLs) particularly for protecting equipments with low ratings, from the consequences of excessive fault currents. A new approach in fault-current limiting in power systems makes use of high-power semiconductor devices, which offer enhanced reliability and improved performance over the conventional types of FCLs. This approach in fault-current limiting in power systems is discussed and a comparison with the existing FCLs is made.