New ZVS-PWM inverter switching limits and operating area

Soft commutation (zero voltage switching or zero current switching (ZVS or ZCS)) allows high frequency operation of power static convertors, reduction of losses and parasitic interferences. The popular PWM inverter cannot naturally benefit from the soft commutation, but only slight changes are to be made to perform ZVS with a PWM inverter (equipped with its filter). A theoretical approach deals with power convertors using soft commutation and the resulting switching limits; it shows that only little restriction in the operating area is induced by these switching conditions. Experimental results on a MOS inverter and a GTO validate this analysis