Zero-voltage-switching interleaved two-switch forward converter with phase-shift control

In this paper, a zero-voltage switching (ZVS) interleaved two-switch forward (ITSF) converter employing a phase-shift control is proposed. Since the proposed converter is based on a two-switch forward (TSF) topology, it has no chance to be a short circuit causing device failure. Furthermore, the interleaving operation of two TSF converters reduces the output filter size. In addition, by applying the phase-shift control on the common clamping diode structure at the primary side, all primary switches can be turned on under ZVS conditions. The operational principle, theoretical analysis, and design consideration are presented. To confirm the performance of the proposed circuit, experimental results from a 480 W, 100 kHz, and 400 V to 48 V prototype are presented.