Research on dual-bridge converter with wide ZVS range and reduced conduction loss

Abstract

Humankind has achieved great advances in industry with the use of fossil fuel, but as a result they are endangered to environmental crises such as climate change nowadays. In addition, in using electric power extracted from the fossil fuel with difficulty, they are abandoning uselessly a substantial amount of the energy during power conversion and cooling process. With these backgrounds, to cope with environmental crises and use the electric energy more effectively, power supplies that cause a vast consumption of energy over entire industries have been focused in many research areas and as a result, the demand of achieving high efficiency of power supply over whole load conditions, which power supply can experience, is being issued every year by many international regulations. There are various power supplies near us. The intended use of these power supplies is different, but they are commonly developed based on distributed power architecture (DPA) for its high efficiency and flexible design. In the DPA, the AC-DC converter converts the AC line input voltage coming from the utility grid into about 400V DC output voltage while compensating the power factor at its input stage for low harmonic contents on the AC utility grid. With the 400V DC output voltage, the front-end converter produces stable DC bus voltages of various levels that are needed by the final load system. And, for the reliable and compact design of power supply, the front-end converter should provide electrical isolation of the system and have both high power density and high efficiency because it occupies generally more than 70% of total power consumption and more than 50% of total space in power supply. For the front-end converter, many topologies can be considered. Among them, conventional phase-shift full-bridge (PSFB) converter is most popular and very attractive topology for medium-to-high power applications, since the voltage stress of all primary switches is always clamp...