Interleaved double series resonant converter

This paper presents an interleaved soft switching converter to achieve the features of zero voltage switching (ZVS) turn-on for power switches, zero current switching (ZCS) turnoff for rectifier diodes at full load, less transformer secondary winding with full-wave diode rectifier topology, and balance primary currents with series connection of the transformer secondary windings. Two circuit modules are adopted in the proposed circuit and they are operated with an interleaved pulse-frequency modulation (PFM). Thus ripple currents at the input and output sides are reduced. In each module, two ZVS converters using the same switches are operated with interleaved half switching cycle. The secondary windings of transformers are connected in series in order to ensure that the primary side currents are balanced. The full-wave diode rectifier topology is used on the output side such that the voltage stress of rectifier diodes equals output voltage, rather than being two times the output voltage as in a conventional center-tapped rectifier topology. Laboratory experiments with a 1000 W prototype are provided to describe the effectiveness of the proposed converter.