A novel control strategy for high-power high-performance AC power supplies

Abstract

This paper presents a novel control scheme suitable for high-power high-performance AC power supplies. The performances of the conventional current-regulated voltage-controlled system with bipolar PWM are first analyzed in detail. The proposed control scheme incorporates dual synchronous PWM technique of single-phase full-bridge inverter and multiple feedback loop. Thanks to this scheme, the AC power supply output voltage can maintain high-quality sinewave at low switching frequency and small output LC filter parameters. At the same time, the system has excellent voltage regulation performance, fast dynamic response, good disturbance rejection, high nonlinear load compatibility, and small voltage modulation value. The validity of the proposed control scheme has been verified on a single-phase 30 kVA experimental prototype.