A soft-switching pulse-width modulation (PWM) converter with parallel connection to realise the zero voltage switching (ZVS) and achieve load current sharing is presented. The leakage inductance of the transformer and output capacitances of power switches are adopted to realise the resonance at the transition interval of switches such that the ZVS turn-on can be achieved. The energy stored in the transformer leakage and magnetising inductances can be released to limit the peak voltage stress of switching devices. To reduce the ripple current on the output capacitor and reduce the current stress on the secondary windings of the transformer, the parallel-connected circuit with an interleaved PWM scheme is used at the output side to share the load current and reduce the output ripple current. The operation principles, steady-state analysis and design equations of the proposed converter are provided in detail. Finally, experiments based on a 1 kW (12 V/84 A) prototype are provided to verify the theoretical analysis and the effectiveness of the proposed converter.

An interleaved series resonant converter with fixed frequency pulse‐width modulation (PWM) is presented to achieve load current sharing, ripple current cancelation, zero‐voltage switching (ZVS) for power switches and zero‐current switching (ZCS) for rectifier diodes. Two three‐level DC converters with clamped diodes and flying capacitor are adopted to share load current. The voltage stress of power switches is clamped at one‐half of DC bus voltage. The interleaved PWM scheme is used to control two converters in order to reduce the output current ripple and size of output capacitor. The series resonant tank in three‐level PWM converter is adopted to realise ZVS turn‐on for all power switches andZCS for rectifier diodes. Thus, the switching losses of active switches are reduced and the reverse recovery losses of rectifier diodes are eliminated. The fixed frequency PWM operation is adopted to regulate output voltage, so that the drawback of a wide range of switching frequency in the conventional series resonant converters is overcome. Finally, experiments based on a scale‐down prototype are provided to verify the effectiveness of the proposed converter.

A new DC/DC pulse‐width modulation (PWM) converter with the functions of zero voltage switching (ZVS) for power switches and zero current switching (ZCS) for rectifier diodes is presented for high‐input voltage and high‐load current applications. Three‐level PWM circuit with two clamped diodes and one flying capacitor is adopted to achieve ZVS turn‐on for all power switches, to balance two input capacitor voltages and to limit the voltage rating of each switch at one‐half of input voltage. Two three‐level PWM circuits with the same power switches are used to share the load current for medium power applications. Series–parallel resonant converter or LLC ( L _r , L _m and C _r ) converter is adopted to achieve ZCS turn‐off for rectifier diodes. Thus, the switching losses of power switches are reduced and the reverse recovery losses of rectifier diodes are eliminated. In order to high load current application, four centre‐tapped rectifiers are connected in parallel to reduce the current rating of rectifier diodes and transformer windings. Experiments are provided to verify the effectiveness of the proposed converter.