Abstract
This paper describes a three-phase AC-DC converter using world-wide PFC (Power Factor Correction) circuit and soft switching full bridge type DC-DC converters. The feature of our new PFC circuit is unity power factor and low harmonics distortion of the input currents, high efficiency and low impressed voltage on the semiconductors. Furthermore, we indicate a method to improve the efficiency and the output voltage ripple at the switching transient of the DC-DC converter using phase shift control. According to the experimental results, the PFC circuit can be applied the semiconductors with the rating voltage 600V at the input voltage AC200V or AC400V. In addition, the input power factor, the efficiency, and the output voltage ripple of the AC-DC converter are good value.