基于辅助网络的软开关Buck变换器

A Soft-switching Buck Converter Based on Auxiliary Resonant Network

提出一种新型的零电流软开关buck变换器,采用辅助谐振网络实现主开关管的零电流关断、辅助开关管的零电流通断,续流二极管的零电流开通,大大降低了开关损耗,特别适用于以IGBT作为开关器件的高电压大功率应用场合。深入分析研究该变换器的工作原理以及软开关控制策略,给出关键电路参数的设计方法。对新电路进行仿真研究,并制作一台输出功率为400W的实验样机进行验证,电路仿真和实验结果验证了所提出的方案是可行的。

A novel zero-current soft-switching Buck converter was proposed.Zero-current turn-off for the main switch and zero-current turn-on and turn-off for the auxiliary switch are achieved by using an auxiliary resonant network,and the main diode is also turned on under zero-current.The switching losses are greatly reduced .It is very attractive for high power application where IGBT is predominantly used as the power switches.The operation principle of the proposed circuit and the control strategy of soft-switching were analyzed in detail,and the design considerations were explained in the paper.A prototype of output power 400 W was built up.The validity of the proposed technique has been verified by computer simulation and experimental results.