A novel full-bridge zero-voltage-transition PWM DC/DC converter with zero-voltage/zero-current switching of the auxiliary switches

In this paper, a novel full-bridge (FB) zero-voltage-transition (ZVT) PWM DC/DC converter topology is proposed. The proposed FB-ZVT PWM DC/DC converter has ZVS of main switches for wide load and line ranges and an advantage of achieving zero voltage and zero current switching of the auxiliary switches using the auxiliary network. The auxiliary network is simply composed of saturable inductor, auxiliary capacitors and auxiliary diodes. With the help of the proposed auxiliary network, the improved FB-ZVT PWM DC/DC converter has so much improved characteristics with respect to the overall system efficiency. The operation principles are explained in detail and the several interesting simulation and experimental results verify the validity of the proposed circuit from a 83 kHz, 1 kW prototype converter using IGBTs.