A Dual-Transformer-Based DC-DC Converter for Wide Voltage Gain and Wide ZVS Range by Utilizing a Sub-Optimal Simplified Control

A dual-transformer-based full controlled dual bridge DC-DC converter catering to the wide voltage gain and the wide zero voltage switching (ZVS) range is introduced in this work. Its structure is simple without extra passive components, and its wide voltage operating range does not rely on the small leakage inductor design and high transformer turns ratio. The conduction loss can be reduced by the active rectifier structure significantly. With the sub-optimal simplified control strategy, the converter can work in wide ZVS range with sub-minimum current stress. The implementation of the control strategy is a simple single closed loop. Two main operating cases of the converter are analyzed meticulously in this paper, including the conversion power features, current stress features, and soft-switching features. The effectiveness of the discussed converter and control strategy are verified by the experiments.