Association of a ZCZVS PWM three-level full-bridge McMurray inverter and an auxiliary power supply

This paper proposes a PWM inverter that allows the main switches to be turned on and off at zero voltage and zero current with controlled di/dt and dv/dt rates. The reverse recovery losses of the main diodes are minimized, and the auxiliary switches are turned on and off in a ZCS mode. The main switches turning-on at zero current can reduce significantly the undesirable effects of the parasitic inductances related to the circuit layout. The commutation losses are practically reduced to zero, as well as the EMI levels. The operation of the ZCZVS PWM Full-Bridge McMurray, using an auxiliary power supply to the control system, is analyzed, and design guidelines for the auxiliary commutation cell are recommended based on this study. Experimental results are presented to demonstrate the feasibility of the proposed 2 kW inverter.