Enhancement of power system transient stability using superconducting fault current limiters

Transient stability investigations consist of studying the rotor oscillatio ns of generators (electro-mechanic oscillations, 0.1-2 Hz) after the occurr ence of a fault of large amplitude, e.g. short circuit. The goal is to indi cate if the generators are capable to stay synchronous after a fault has oc curred. The fault duration is one of the most important factors to be deter mined. In fact, the shorter the fault, the more the maintaining of synchron isation can be guaranteed. Now in case of a fault, a fault current limiter has an extremely fast current transition in comparison to electro-mechanic time constants. This implies a quasi-instantaneous elimination of the fault through a limitation of the current and consequently a better ability to m aintain the synchronisation of the system. We recall that in a classic syst em, the elimination of a fault, by opening a circuit breaker, is carried ou t in two or three cycles in the best case. We have here studied a simple, r adial electric network configuration with a machine and an infinite network . The study covers simulations of a fault that can occur in a network and t he consequences of the recovery time of the fault current limiter.