Achieving a wide input voltage and output power load range step-down DC-DC conversion with good full range efficiency at 4kW

This paper describes an original topology for a step-down DC-DC converter. This converter is a resonant converter with zero voltage switching and zero current switching. Regulation of the converter is done by PWM and variable frequency; this provides good regulation, from no load to full load. A prototype was built for an output power of 4kW, an input voltage range of 280VDC to 440VDC, and an output voltage of 14VDC. The prototype converter has an efficiency of 92-94%, is cost effective, and a good fit for high power and high current applications. The authors suggest that the presented topology is a better alternative to a typical phase-shift topology, with an additional advantage of being bi-directional.