Study on the four quadrants operation of ITER poloidal field converter system

This paper describes a four quadrants converter system for the international fusion tokamak device (ITER) which is now under construction in the south of France. The ITER poloidal field (PF) converter system is thyristor-based and rated for 82 MVA, providing up to ±1.05 kV/± 55 kA dc power to the superconducting magnets to generate a controlled rotating magnetic field for nuclear fusion reactions. First, this paper describes the basic operation modes of the converter system. Then, its dynamic behaviors are analyzed based on the circuit analysis, and control strategies are put forward. Moreover, experiments based on a prototype are performed to verify the effectiveness of the theoretical analysis.