Current-fed full-bridge boost converter with zero current switching for high voltage applications

This paper presents a current-fed full-bridge boost converter with zero current switching (ZCS) based on constant on-time control for high voltage applications. The proposed converter utilizes the leakage inductor and the winding parasitic capacitor resonant tank to achieve ZCS. In order to achieve ZCS under wide load range, the turn-on time of the full-bridge boost converter is kept constant and the output voltage is regulated via frequency modulation. Finally, a laboratory prototype converter with 1 kV/600 W is implemented to verify the ZCS performance of the proposed converter. The highest efficiency of the proposed converter is 92%.