New interleaved three-level ZVS converter

Abstract

An interleaved three-level DC/DC zero voltage switching (ZVS) converter is presented in this paper. There are two circuit modules in the proposed converter to share the load current and power rating. The interleaved pulse-width modulation (PWM) scheme is adopted to control two circuit modules such that the ripple currents at the input and output sides are reduced. Each circuit module has two three-level DC/DC converters with the same power switches to reduce the voltage stress of each MOSFET at Vin/2 and achieve load current sharing. Thus, the current stress and power rating at the secondary side components are reduced. The current double rectifiers are used at the secondary side to partially cancel the output ripple current. Thus, the sizes of the magnetic components and output filter capacitance are reduced. Due to the resonant behavior by the resonant inductance and resonant capacitance at the transition interval, MOSFETs can be turned on at ZVS under a wide range of load condition and input voltage. The experimental results based on a 1kW prototype are provided to verify the effectiveness of the proposed converter.