Design and development of acceleration grid power supply-conversion system for CFETR N-NBI.

• A new approach to the CFETR N-NBI accelerator grid power supply-conversion system topology is put forward. • The parameters and operation principle of the proposed conversion system are designed and analyzed. • CFETR AGPS simulation process is carried on to verify that the newly-design scheme is feasible. The acceleration grid power supply (AGPS) is developed to provide accelerator power for China Fusion Experimental Rector (CFETR) Negative-ion Neutral Beam Injection (N-NBI) system. The rated output parameters of this AGPS are -1000kV/80A/80MW. The preliminary design of the AGPS is proposed in this paper. To improve the steady-state and dynamic performance of the AGPS, a new CFETR AGPS conversion system (AGPS-CS) based on three-level neutral point clamped (3L-NPC) rectifier and five-level neutral-point-clamped/cascaded H-bridge (5L-NPC/H) inverter is presented. The parameters of AGPS-CS are obtained theoretically, and simulations are used to verify its operational performance and show the effectiveness of the proposed topology. Results indicate that the proposed design provides good input-output features and can meet the requirements of the CFETR N-NBI system. This solution can also be used as a reference for the design of large-power high-voltage power supply. [ABSTRACT FROM AUTHOR]