Soft-switching techniques for PWM full bridge converters

Abstract

This paper proposes a family of modulation strategies for PWM full bridge converter including nine modulation strategies, which can be classified into two kinds according to the turn-off sequence of the two power switches in the oblique diagonal line of the two bridge legs. The concept of leading leg and lagging leg is introduced to realize soft-switching for PWM full bridge converters. The realization of soft-switching for both leading leg and lagging leg is proposed, based on which, soft-switching techniques for PWM full bridge converters can be classified into two kinds: zero-voltage-switching (ZVS) and zero-voltage and zero-current-switching (ZVZCS). The modulation strategies and topologies for the two kinds of soft-switching PWM full bridge converters are proposed.