New phase shift full bridge converter with wide ZVS ranges and low conduction losses

Abstract

In this paper, a new zero voltage switching (ZVS) phase shift full bridge (PSFB) converter with low conduction losses is proposed. It is based on the PSFB converter with series-connected two transformers (SCTT), which features wide ZVS ranges. By adding a capacitor, the proposed converter overcomes the disadvantage of the based converter, such as the high circulating energy. Furthermore, the turn ratio of the transformers can be increased as well. Therefore, high efficiency of the proposed converter can be achieved. Operational principles and experimental results for a 100 W (5 V, 20 A) prototype are presented to validate the proposed converter.