中文摘要：

鉴于电动车充电电源移相全桥主电路拓扑的特点，在考虑变压器漏感、原边外加谐振电感和二极管寄生参数的基础上，建立了变压器二次侧整流桥换流时的等效模型，依据该模型分析了变换器输出整流桥寄生振荡产生尖峰电压的机理，讨论了各参数对寄生振荡的影响规律。然后针对二次侧寄生振荡产生的原因，采取了副边加缓冲电路以及原边加箝位电路的复合网络设计方法来抑制电压尖峰，并对比了常用策略，分析了该复合网络的优越性。 Matlab仿真和硬件电路实验结果表明，在所设计的18 kW移相全桥ZVS变换器中采用的复合型优化缓冲电路，可有效抑制输出整流桥上的振荡尖峰电压，符合大功率充电电源高可靠性的要求。

英文摘要：

Taking transformer leakage inductance , extra oscillation inductance and parasitic parameters of diodes into account ,an equivalent model of rectifier bridge current commutation after secondary winding of the transformer has been built combining with the characteristics of phase-shift full-bridge circuit of EV charger .Then mechanism of the parasitic oscillation and influences by different parameters has been analyzed .Aiming at the parasitic oscilla-tion, composite network of snubber circuits has been designed to depress the voltage spike , in which buffer circuit after secondary winding and clamping circuit before primary winding has been adopted .In contrast to common strat-egies, superiority of the method has been discussed .The simulation on Matlab and hardware experiment have proved that the designed 18kW phase-shift FB converter with the composite network snubber circuits can decrease the voltage spike efficiently , meeting the demands of high stability for high power EV charger .