SOFT-SWITCHING TECHNIQUES IN PWM CONVERTERS

Recently, a number of soft-switching pulse-width-modulated (PWM) conve rter techniques have been proposed, aimed at combining the desirable f eatures of both the conventional PWM and resonant converters while avo iding their respective limitations, In this paper, three classes of ze ro-voltage soft-switching PWM converters (namely the zero-voltage-swit ched (ZVS) quasi-square-wave converters, ZVS-PWM converters, and zero- voltage-transition PWM converters) and two classes of zero-current sof t-switching PWM converters (namely, the zero-current-switched PWM conv erters and zero-current-transition PWM converters) are reviewed, and t heir merits and limitations are assessed, Experimental results of seve ral prototype of converters are presented to illustrate each class of converters.