Design methodology to achieve high-efficiency isolated ZVS DC/DC converters

This paper presents a design methodology for isolated Zero Voltage Switching Phase-Shifted (ZVS-PS) DC/DC converters, applied to Double Half-Bridge (DHB) converter as well as to the well-known Full-Bridge (FB) converter. Here, the DHB topology is introduced as an alternative to the FB, presenting an additional feature of operating ZVS over the entire load range, regardless of the duty-cycle, from zero to the maximum output voltage. The purpose of the design methodology used is to find out the converter's parameters operating at ZVS under full load range for DHB and wide load range for FB. The design methodology proposed computes and determines the parameters from constraints and trade-offs, so that to guarantee high performance and ZVS operation for both converters. Therefore it has been carried out to minimize the converter losses, reaching an estimated efficiency close to 97%, as well as the experimental one.