Analysis of Transient Recovery Voltage of 500 kV Line Considering Current Limiting Reactor

Abstract

To limit the short-circuit current level, the method of series current, the limiting reactor is used to limit the short-circuit current, and the common access mode of the current limiting reactor is direct access. The series current limiting reactor can effectively limit the short-circuit current in 500kV power system, but after it is connected to the system, it will increase the transient recovery voltage steepness in case of a circuit breaker breaking fault and affect the normal breaking of the circuit breaker. Based on a 500 kV current limiter project, the influence of a lower limit current reactor on the recovery voltage of circuit breaker under different fault conditions is studied by using electromagnetic transient simulation software EMTP. The results show that the transient recovery voltage of the circuit breaker will exceed the standard value after the reactor is connected. When capacitors above 600nF are connected in parallel to the current limiting reactor, the transient recovery voltage could be limited to the standard range.