Circuit configuration of the GTO converter for superconducting magnetic energy storage

The authors discuss the circuit configurations and design of two AC-to-DC power converters for superconducting magnetic energy storage (SMES) using gate-turn-off (GTO) thyristors. The circuits are current-source rectifiers, so that suppressing the overvoltage on the GTOs during commutation is an important consideration. Moreover, to get high conversion efficiency it is necessary to handle the commutation energy properly. Two circuits are presented for this purpose, and the detailed computer simulation of these circuits is discussed. The resulting design policies and characteristics for both circuits are described, and the best choice of converter circuit for SMES is determined.<>