Development of a 25kW High-frequency Phase-shift PWM Full-bridge DC/DC Converter for a Wide Range of Load Applications

This paper describes a 25 kW phase-shifted full-bridge converter (PSFB) operating at a high frequency. The switching frequency was set to 500 kHz, and a SiC MOSFET full-bridge module was applied to the PSFB for high power density, which contains state-of-the-art semiconductor device technology, along with PCB and transformer designs optimized for high frequency. Because the applicability to a wide range of load conditions is a key concern, this paper also analyzes the conditions for achieving broad zero-voltage switching (ZVS). It proposes a gate driver that fulfills this purpose based on the analysis. The enhanced operation, incorporating design considerations, was verified through simulations and experiments under various resistive load conditions.