Control Strategies of Multiple Current-Source PWM Converters for a 20MW SMES System

Abstract

Control strategies for multiple current-source converters ^[1] employing large capacity gate turn-off (GTO) thyristors are applied for a 20MW Superconducting Magnetic Energy Storage (SMES) system. Suitable control method and control block diagrams are proposed by taking much use of the multiple structure. Pulse Width Modulation (PWM) control method of current source converters for the purpose of high efficiency and low harmonic distortion is explained. A unique control method for small power output is shown. The results of digital simulation by Electro Magnetic Transient Program (EMTP) are provided to validate the proposed control methods of SMES power conditioning.