一种采用辅助电路的ZVZCS PWM TL直流变换器

A ZVZCS PWM TL Converter Using Auxilary Circuit

提出一种新型的ZVZCS PWM TL直流变换器,在变压器的次级侧附加一个辅助绕组,整流得到的辅助电压,为滞后管创造零电流条件,较好地解决了滞后管轻载下软开关难的问题。新的主电路拓扑减小了高压下功率器件的电压应力。本文分析了该变换器各时段的工作原理,并提供了设计参考和实验结果。

This paper proposes a novel zero-voltage and zero-eurrent-switching(ZVZCS) PWM three-level converter, which introduces an auxiliary winding in transformer secondary side. The rectifier voltage of auxiliary winding provides ZCS condition for lagging switches. The problem that soft switching of lagging switches is difficult to be achieved at ligh load is resolved very well. In the new circuit topology, voltage stress of power devices is reduced when input voltage is high. The operation principle duing each period of time is analyzed, design considerations and experimental rsults are presented.