Zero-Voltage and Zero-Current Switching Dual-Transformer-Based Full-Bridge Converter With Current Doubler Rectifier

A novel dual-transformer-based full-bridge (DT-FB) converter with a current doubler rectifier (CDR), which can solve the drawbacks of existing FB converters, is proposed in this article. In the primary side of the proposed converter, two switching legs, two transformers, and two blocking capacitors form two half-bridge inverters. The secondary side composes of two output filter inductors and four power diodes, which connect with the form of the CDR. By employing this structure, a wide range of zero-voltage switching for leading-leg and zero-current switching for lagging-leg can be achieved. In the proposed converter, the output power is shared by two small-sized transformers and inductors instead of large-sized ones, which contributes to the improvement of power density and efficiency. Compared with the traditional FB converter, the proposed converter can obtain higher voltage gain, better rectified voltage, and lower current ripple. The operation principle, theoretical analysis, and design considerations of the proposed converter are described in this article. A prototype with 300–380 V input and 100 V/ 10 A output is designed and tested to confirm the effectiveness of the proposed converter.