Abstract: Full-bridge zero-voltage-switched PWM converter combines advantages of the PWM control technique and ZVS resonant technique. However, full ZVS is achieved only under large load current because resonant tank of this circuit is maked up of the parasitic capacitance of the power semiconductors and the leakage inductor of the transformer primary. Two saturable inductor as magnetic switch is added to secondary coil, so output filter inductor is always reflected to primary and assists resonant transition. Full ZVS is achieved under lower load current. The above mentioned investigated results is validated by the computerized simulation and hardware circuit experimentation.

Key words: Arc welding inverter power source, Computerized simulation, Resonant inductor, Soft switching