Control and operation strategy design of ITER coil power supply system

•The comprehensive control and operation strategies applied in large-scale ITER Coil Power Supply System are designed to accommodate the uncertain plasma operation.•The operation systems and associated functions are devised to fulfill operation strategies under the control of plasma control system by real time communication.•The various control strategies and corresponding operation systems are verified by simulation and test results. The large-scale ITER coil power supply system will generate huge current for superconducting magnets by plenty of AC/DC converters, which are based on thyristor technology on various circuits. A comprehensive consideration on design, manufacturing, testing and commissioning is the foundation to guarantee the safety operation of the CPSS system. This paper presents the design of converters control and operation strategies according to different typical circuit topologies. As well as illustrate the corresponding operation systems with associated functions to achieve those operation strategies. 2-Quadrant, 4-Quadrant and sequential control operation strategies are applied in corresponding PF (Poloidal Field), CS (Central Solenoid), CC (Correction Coil) and VS1 (Vertical Stability) converters with associated current closed-loop or voltage open-loop control during plasma operation. Three individual operation systems are comprised of TF, PF/CS and CC conventional systems with two architecture hierarchies to perform the control strategies and fulfill the real-time communication with central system. Typical simulation and test results are presented to verify the control strategies in accordance with the manufacturing and factory acceptance test. The converters will be installed in the ITER site soon and all the control strategies will be tested on the following commissioning phase.