An Interleaved ZVS Forward Converter with Series Input Parallel Output Structure

An interleaved zero-voltage-switching (ZVS) forward converter for high input voltage and high output current applications is proposed in this paper. The converter consists of two active-clamp forward converter cells in series input and parallel output connection to share the input voltage and output current. The interleaved operation is employed to diminish the current ripple on the output capacitor. The resonant inductance and the output capacitances of switches are utilized to realize the resonance at the transition interval of switches such that the ZVS turn-on operation for all switches can be achieved. All these features make the proposed converter suitable for high input voltage, high output current and high efficiency applications. The operating principle, characteristics and design considerations of the proposed converter are presented. Finally, the experimental results of a prototype converter with an input of 400 V and an output of 24V/20A are provided to verify the validity of the proposed converter.