Novel zero-voltage and zero-current-switching full bridge PWM converter using transformer auxiliary winding

A novel zero voltage and zero current switching (ZVZCS) full bridge (FB) pu lse width modulation (PWM) converter is proposed to improve the demerits of the previously presented ZVZCS-FB-PWM converters [5]-[8], such as, use of lossy components or additional active switches. A simple auxiliary circuit which includes neither lossy components nor active switches provides ZVZCS conditions to primary switches, ZVS for leading-leg switches and ZCS for la gging-leg switches. Many advantages including simple circuit topology, high efficiency, and low cost make the new converter attractive for high power (>2 kW) applications. The operation, analysis, features and design consider ations are illustrated and verified on a 2.5 kW, 100 kHz insulated gate bip olar transistor (IGBT) based experimental circuit.