中文摘要：

提出一种只采用一个辅助开关,即能实现所有开关的零电压开通,并能抑制二极管反向恢复的高效率软开关三相并网逆变器。逆变器可以采用空间矢量调制（SVM）策略,主开关和辅助开关具有相同且固定的开关频率。分析了软开关三相并网逆变器的开关过程,给出了谐振参数设计步骤。研制了20 kW实验样机并完成了实验验证,实验结果表明,并网逆变器满载效率达到98%。

英文摘要：

A three-phase grid-connected inverter with high efficiency soft switching is proposed,which uses only one auxiliary switch and can realize zero voltage switching（ZVS） operation for all switching devices,as well as can suppress the anti-parallel diode reverse recovery voltage.Space vector modulation（SVM） strategy can be adopted for this inverter with the main and auxiliary switching devices operating at the fixed and same switching frequency.The soft switching process of this inverter is analyzed,and the design procedure for resonance parameters is described.A 20 kW prototype is built to verify the theory,and efficiency of the inverter with full load can attain to 98%.