High Power Test Facility 500 kA Pulse Current Sharing Control

Direct current (DC) high power test facility is designed, built and managed by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), which aims at completing the components type test of International Thermonuclear Experimental Reactor (ITER) Poloidal Field (PF) power system. The pulse current of DC high power test facility is rated at 500 kA which is also the largest pulse current in the world. Four thyristor-based ac/dc. converter modules are paralleled to handle 500 kA pulse current in DC high power test facility for less than 1 second. Due to the huge transient current, any unbalance current of each converter module could lead to power off or equipment damage. In this paper, the dynamic current sharing control of 500 kA pulse current is studied and the effective control strategy is proposed based on the design requirement. In order to ensure the dynamic characteristics and the system stability, the proportional control with the incremental control algorithm is adopted. The experiments carried out on DC high power test facility proves that the current balance coefficients of 500 kA pulse current is 0.82 which satisfy the design requirement completely.