Simulation study of bridge type solid state fault current limiter

Short circuit is a serious fault in high-voltage power network. If the fault current can be limited, system reliability, safety and cost effectiveness will be improve. With the development of the power system, short circuit capacity becomes a serious limiting factor to it. This paper presents a novel bridge type solid state fault current limiter (FCL) based power electronics technology for high-voltage electrical network (10kV or higher). The FCL integration with the electrical network has been simulated using simulation package PSIM. It is shown that in normal operation condition the limiter has no obvious effect on loads. However it will insert a impedance automatically without delay to limit the short circuit current when fault happens. There is no oscillation as well as overvoltage excited by the limiter when the fault current is switched off. The operating principle and control strategies of FCL are discussed in detail. The proposed system is numerically tested, it proved that the theoretical prediction and the current limiting performance is satisfactory for practical use.