高效率LLC同步整流数字双环均流控制策略

High Efficiency LLC Synchronous Rectification Digital Double Loop Current Sharing Control Strategy

为了提高电源的功率密度,LLC变换器的输出侧通常会采用变压器副边多组抽头、多个功率开关管并联的方式,能够实现低压大电流的功率输出.这种方式会带来各个功率管不均流的问题,加速某些功率管的老化,影响整个电源的寿命,增加电源损耗.为此,提出一种同步整流的数字双环均流控制策略,通过仿真实验分析验证了该方法的有效性与可行性.

In order to improve the power density of the power supply,the output side of LLC converter usually adopts the mode of multiple groups of taps on the secondary side of transformer and multiple power switches connected in parallel,which can realize the power output of low voltage and high current.This way will bring the problem of uneven current flow in each power tube,thus accelerating the aging of some power tubes,affecting the life of the whole power supply and increasing the power loss.Therefore,a digital double-loop control strategy of synchronous rectification and current sharing is proposed,and the effectiveness and feasibility of this method are verified by simulation analysis.