Chengxian 220kV Thyristor Controlled Series Compensation: Parameters Design, Control & Overvoltage Protection

A new Thyristor Controlled Series Compensation (TCSC) has been successfully applied at the 220kV Chengxian substation of Bikou-Chengxian-Tianshui transmission system in Gansu power system. This paper introduces some technical considerations on TCSC, including parameter design of the thyristor controlled reactor, metal oxide varistor (MOV) and damping circuits, basic control strategy of TCSC, transient recovery voltage of circuit breaker, sub-synchronous resonance (SSR), operation condition of thyristor valve and switching surge on the transmission line with TCSC.