An asymmetrical ZCS-PWM half-bridge DC-DC converter with active auxiliary edge-resonant snubber

A novel zero current soft-switching (ZCS)-PWM cell-assisted asymmetrical half-bridge (AHB) DC-DC converter topology with a high frequency (HF) link is proposed in this paper. The newly-proposed DC-DC converter consists of a PWM-controlled single-ended half-bridge HF inverter and a center-tapped rectifier linked with a HF transformer. In order to attain the wide range of ZCS commutation in the primary-side HF inverter, the active edge resonant snubber cell composed of a switched capacitor and a lossless inductor is adopted in the half-bridge leg, providing ZCS commutation for a wide range of output power under constant switching frequency. The operation characteristics of the DC-DC converter proposed here are described, and its feasibility data is demonstrated and evaluated with simulation and experimental results.