基于移相全桥的混合型变换器的研制

Research and Development of Phase-shifted Full-bridge Hybrid Converter

针对传统移相全桥电路在轻载条件下滞后桥臂而难以实现软开关的问题,在研究移相全桥和半桥LLC的基础上,通过对共用滞后桥臂相结合的优化,设计了一种共用滞后桥臂的零电压开关的混合型变换器,在保证该桥臂开关管实现宽范围的ZVS情况下,实现变换器以并联的形式输出,并使得全桥原边电流续流期间复位到零,减小环流损耗。分析了该混合型变换器工作原理和电路特性,最后研制了一款1.44 kW的实验样机,进行了实验验证,并给出了实验结果。

The traditional phase-shifted full-bridge circuit lags the bridge arm under light load conditions and is difficult to achieve soft switching.Based on the study of phase-shifted full-bridge and half-bridge LLC,a hybrid converter with zero-voltage switching with a shared hysteresis bridge arm is designed by optimizing the combination of the shared hysteresis bridge arm.In the case of ensuring that the bridge arm switch tube can achieve a wide range of ZVS,the output of the converter in parallel is realized,and the full-bridge primary current is reset to zero during the freewheeling period to reduce the circulating current loss.The working principle and circuit characteristics of the hybrid converter are analyzed.Finally,a 1.44 kW experimental prototype is developed,and the experimental results are given.