Center-tapped transformer based bidirectional dc-dc converter with wide input voltage range

In this paper, a center-tapped transformer based bidirectional dc-dc converter with full ZVS operating range is proposed for wide input voltage range applications. The soft switching analysis in different modes is carried out and a simple and effective control strategy, allowing extending the practical ZVS to the whole operating range, is proposed. By dynamically adjusting the phase-shift angle between the two output half-bridges, all power switches can operate with ZVS over the entire load range. At heavy loads, no output-bridge phase-shift angle is required and the two output bridges operate in parallel to minimize the conduction loss. Experimental results are given to verify the effectiveness and advantages of the proposed converter.