Analysis and implementation of a new zero-voltage switching dc converter with less active switches

摘要

A new zero-voltage switching (ZVS) DC converter with less power switches is presented in this study. The proposed converter includes three subcircuits connected in parallel with the same switches to share load current. Thus, the proposed converter has less switch counts compared with the conventional parallel ZVS DC/DC converter and the output filter inductances and the transformer windings are reduced. Three-level diode clamped converter is used to reduce the voltage stress of switches at V_in/2. The input two capacitor voltages are automatically balanced by adding two flying capacitors in three-level DC/DC converter. The current doubler rectifiers are used at the output side to reduce the output current ripple. The output capacitances of metal oxide semiconductor field effect transistors (MOSFETs) and resonant inductances are resonant at the transition interval. Thus, MOSFETs can be turned on under ZVS. Finally, experiments are provided to verify the effectiveness of the proposed converter.