Fault Detection System for 500kV AC Fault Current Limiter Based on High-Coupled Split Reactor

Aiming at the problem of limiting high short-circuit current in 500 kV AC power grid, we develop an economical-type fault current limiter (FCL) based on high-coupled split reactor (HCSR), namely, HCSR-FCL. This paper addresses the fault detection system of HCSR-FCL. Firstly, we introduce the working principles of HCSR-FCL and give the system design of HCSR-FCL control system. Subsequently, we discuss the realtime requirement of the HCSR-FCL control system, and propose a fast short-circuit fault detection algorithm based on three-phase current square ratio. Finally, simulation verification on RTDS platform is given. Experimental results show that the proposed algorithm can detect short-circuit fault rapidly and robustly. When short-circuit occurs, the control system designed can output control signals, which drives the FCL into operation and meets requirements of the national key project.