一种新型全桥软开关变换器的研究

Research on a Novel Full-bridge Soft-switching Converter

为增加全桥软开关电源的负载变化范围,设计了一种新型的全桥移相脉宽调制(PWM)零电压零电流(ZVZCS)软开关变换器。在此电路中,超前桥臂通过增加一个由两个电容及一个电感组成的辅助电路,使超前桥臂在轻载时仍能实现超前桥臂的零电压开关变换;滞后桥臂提出一种改进的电路拓扑结构,该拓扑使负载电流在满载时仍能实现其滞后桥臂的零电流开关变换,并可有效降低整流二极管的电压应力。研制了一台输出48 V/10 A的全桥移相ZVZCS软开关电源样机,通过试验验证了理论分析的正确性。

In order to increase the range of load change,a novel full bridge phase-shift pulse width modulation（PWM） zero voltage zero current switching（ZVZCS） soft converter is designed.In this circuit,an assistant circuit which is made up of two capacitors and an inductance is added in leading-lag,it can achieve zero voltage switching under light load.An improved circuit topology is added on lagging-leg,it can achieve zero current switching under heavy load.Thus,it can depress the voltage stress of diode.A full-bridge phase-shift PWM ZVZCS soft converter model machine with output of 48 V/10 A is prepared,the theoretical analysis is proved correct according experiment.