Study On Excitation Control System Of Bridge Type Fault Current Limiter With Magnetic Bias

Based on a lot of simulation results on some kinds of thyristor converter system with frequency reverse electromotive force load,the author does some research on operating characteristics of single-phase and three-phase bridge controlled rectifier (TBCR) system in this paper, and discusses its load characteristic. The article focuses on the design of intelligent controller.This paper proposes a design method for an excitation control system of the bridge type fault current limiter with magnetic bias. The proposed excitation control system consists of three single-phase bridge type fault current limiters with magnetic bias, three current-limiting reactors, excitation power supply system and the operation state condition monitoring of power grid. The controller which adopted DSP and FPGA as the core processor is implemented to realize the proposed excitation control system. The controller is used to provide excitation current for FCL. When the short circuit fault happens, the excitation controller can make a judgment in time, and then receive the control parameters from the monitor system of power grid by the CAN Bus.The control software and hardware of the proposed excitation control system are presented respectively. Based on DSP and FPGA technique, the digital excitation controller is designed to overcome the even frequency reverse electromotive force. The system uses Fuzzy self-adaptive PID algorithm to implement intelligent control. Various short circuit experiments are carried out in the developed sample machine of FCL with rated voltage of 380V and rated current of 150A. The experimental results show that the designed scheme of the control system is feasible and effective and can realize the desired purpose. It is stable and reliable.