Fault current limiter with solid-state circuit breakers

Abstract

Switching of power circuit breakers is an important technical issue, especially at short circuit, since the fault current cause thermal and dynamic stresses, and the power quality worsens. Recently, the development of distributed renewable electricity induces the short circuit protection problematic because the distributed production of electric energy cause the transport networks to lose their radial character and disturbs the protective relays coordination. The modern technologies for power switching uses static fault current limiters, which offers a viable solution to remove the problems caused by large fault currents in the system. An appropriate design of the current limiting device reduces the thermal and dynamic stress and limits the fault current to a low value. The static switches are based on high power semiconductor devices that offer advantages compared to mechanical switches. Using a fault current limiter that minimizes the effect of distributed generation of electricity in a radial network on the co-ordination of protective relays is a solution to this problem in terms of switching speed and lifespan of power switches.