DESIGN AND CONTROL STRATEGIES OF CONVERTER FOR SMES-UPS BASED ON TF SUPERCONDUCTING COILS OF TOKMAK

SMES-UPS based on torodial field supercon- ducting coils (TFSC) of the superconducting tokamak can be used to avoid the breakdown of the cryogenic and vacuum system because of the deep voltage sag or other grid faults during the tokamak抯 experiment, which will result in the quench of the superconducting coils of tokamak. A current source converter for this SMES-UPS is proposed, which can serve as the excitation PS of TFSC as well as the backup power supply for critical loads. Furthermore,the suitable control strategies and control block diagrams for different aims are described respectively. The digital simulation results by MATLAB are provided to validate the proposed control strategies for SMES-UPS.