基于π型无源辅助网络的新型ZVS全桥变换器

Novel Full Bridge Converter With π Type Auxiliary Network

提出一种新颖的采用π型无源辅助网络的零电压开关(zero voltage switching,ZVS)全桥变换器,它是在传统全桥拓扑上加入由电感和电容组成的无源辅助网络,从而可在宽电压输入和全负载范围内实现原边开关管的ZVS。详细分析该变换器的工作原理及特性,并对电路关键参数进行设计。在此基础上,设计完成一台1kW(54V/20A),开关频率为100kHz的原理样机,实验结果验证了该拓扑的优点。

A novel zero voltage switching （ZVS） full-bridge converter with π type auxiliary network was proposed. The converter topology presented here employs an asymmetrical auxiliary network consisting of a few passive components. With this auxiliary network,the full bridge converter can achieve ZVS for all primary switches in a wide load range. The operation principle of the circuit was demonstrated,and the steady analysis was performed. Based on the analysis,a criterion for optimal design was given. Finally,the experimental results from a 1 kW（54 V/20 A） prototype were presented to confirm the operation,validity,and features of the proposed converter.