A novel synchronous rectifiers based ZVS-PWM DC-DC power converter with extended soft-switching operation range

摘要

In this paper, a full bridge edge-resonant zero voltage mode based soft-switching PWM DC-DC power converter with a high frequency transformer link is presented. Active power MOSFETs operating as synchronous rectifier are implemented in the rectifier stage to reduce conduction losses and also to extend ZVS commutation area of the primary side power MOSFETs from rated to zero load without requirement of a magnetizing current. The operation of this phase-shift PWM controlled converter is described in comparison with conventional ZVS phase-shifted PWM DC-DC power converter with diodes rectifier. Moreover, the experimental results of the switching power losses analysis are discussed in this paper. The practical effectiveness of the power DC-DC power converter treated here is proved from a practical point of view by using 2.5 kW, 32 kHz breadboard circuit. An actual efficiency 97% of this converter is measured in the experiment.