零电压开关不对称半桥DC／DC变换器

近年来，软开关技术得到广泛的发展与应用，出现不少高效率的电路拓扑，其中不对称半桥就是典型的适用于中低功率的直流变换电路。它充分利用电路本身的分布特性，利用变压器漏感和开关寄生电容的谐振来实现零电压开关，减少了开关的导通损耗。介绍了一种在变压器原边带箝位电路的不对称半桥零电压开关电路。该箝位电路能明显减少输出二板管的反向恢复效应，提高变换器的效率。并对该软开关电路的工作原理和实现方法做了详细的分析，通过一台300W，100kHz的实验样机，证实了该方法的有效性。

Zero-voltage-switching Asymmetrical Half-bridge DC/DC Converter

In recent years, soft-switching technology has been widely developed and used. A lot ot circuit topologies with high efficiency have been presented. Among these topologies, asymmetrical half-bridge converter is a typical DC/DC converter used for power no more than 1000W. A novel asymmetrical half-bridge DC/DC converter with a clamping circuit connected to the primary side of the transformer is presented. This topology has many advantages such as it can reduce the reverse recovery effects of the output diodes and increase the efficiency. Its operation principle and realized method have been detailed discussed, in the same time, a prototype of the soft switching converter with 300W, 100kHz verified the effect of this method.