A hybrid ZVZCS phase-shift full-bridge converter with series/parallel auto-regulated transformer windings

This paper presents a new hybrid zero-voltage zero-current switching (ZVZCS) phase-shift full-bridge converter with stepless series/parallel auto regulated transformer windings. With the proposed topology the secondary windings of the transformers work in series when the input voltage is low but in parallel when the input voltage is high. It can be employed in wide input voltage range application according to the extended conversion gain of the converter. Meanwhile, interleaved operation can reduce the current stresses, the conduction loss of the primary switches and the current ripple in the output filter. A prototype with 200-400V input and 50V/20A output is built up to verify the theoretical analysis.