A novel high frequency isolated dual-transformer LCL-type resonant AC/DC converter to minimize total loss over whole load range

Abstract

A modified dual-transformer topology with associated analysis is presented in this paper, which maintained soft-switching operation and depressed current stress to achieve higher conversion efficiency. The proposed resonant converter it contained two transformers and adopted phase shift modulation to regulate output power, so that converters output power can be controlled in simple and stable strategy. A method to depress resonant current stress is proposed in design progress. With lower current and fewer power components is helpful to reduce conduction loss. Based on the steady-state analysis, a design example is given. Finally, experimental works and comparison work on a lab prototype are performed, which validate the performance improvement of the proposed converter.