副边调制三电平软开关直流变换器

Secondary modulation three-level soft switching DC-DC converter

提出了一种副边调制软开关三电平直流变换器.该变换器具有如下优点:原边开关器件仅承受一半输入电压应力,且不需要额外均压器件;副边LC滤波器前的电压波形是三电平,可有效减小输出LC滤波器的体积;原边开关器件可实现宽范围零电压开通;副边开关器件可实现零电流关断.分析了电路的工作原理及软开关特性,并进行了比较及实验研究,实验结果表明该电路工作原理正确,能够正常工作.

A secondary modulation soft switching PWM three-level (TL) dc-dc converter is proposed.The proposed converter has following good features:Four primary switches sustain only one-half of the input voltage,and no auxiliary primary clamping device is required;the secondary rectified voltage before the LC filter is a TL waveform,which significantly reduces the requirement of the output filter.All primary switches can obtain zero-voltage switching (ZVS) down to zero loads.The secondary switches can obtain zero-current switching (ZCS).The operation principle and soft switching characteristics are presented in this paper.In addition,comparison and the experimental results from a prototype are also included to verify the proposed converter.