Research on ZVS full-bridge converter with reduced conduction loss

Abstract

Nowadays, climate change becomes serious problem in all around country. Especially, because of global warming problem, every country is suffered from various natural disasters. To prevent these changes, every industry keeps requiring the increase in energy conversion efficiency. And this world wide issue directly affects the power supply market, which is mainly energy-consumption part of many devices. Hence, the market for power supply continuously demands high efficiency and high power density of power supply. Generally, distributed power system (DPS) is widely used in many power supply applications for its high performance, efficiency, and reliability. The DPS is composed of three parts: power factor correction (PFC), front-end DC/DC converter and point of load (POL) converter. The PFC stage receives the AC line input voltage and converts it into 200~400V DC output voltage and it improve the power factor of system. The front-end DC/DC stages provide electrical isolation of the system and it produces stable DC bus voltage or required output voltage of system. The POL converter tightly regulates the output voltage according to the load system. Among these parts, the front-end DC/DC converter is treated as critical part for the high efficiency and high power density of DPS, since it occupies more than 70% of total power consumption and more than 50% of total space in DPS. For the front-end DC/DC stages, many topologies have been researched in recent century. Among them, conventional phase-shift full-bridge (PSFB) converter is most popular and very attractive topology for the medium-high power application, since it has some desirable features such as low current/voltage stress and ZVS operation of all primary switches by utilizing the transformer leakage inductance and intrinsic capacitances of switches without any additional circuit. However, the conventional PSFB converter has main two drawbacks. First of all, ZVS operation of conventional PSFB converter is de...