A New ZVT-PWM Converter with Reduced Circulating Current Losses

Abstract

A new auxiliary circuit for single switch, zero-voltage-transition pulse width modulated (ZVT-PWM) converters is proposed in this paper. This circuit can assist the zero-voltage-switching (ZVS) operation of the main converter switch with lower auxiliary switch switching losses than many previously proposed ZVT-PWM converters, but with less circulating current than that found in ZVT-PWM converters with resonant type auxiliary circuits. The paper will review the operation of auxiliary circuits in ZVT-PWM converters and then discuss the properties and characteristics of the new circuit. Experimental results obtained from a prototype of a ZVT-PWM boost converter with the new auxiliary circuit are presented