中文摘要：

提出了一种新型软开关三相并网逆变器,通过在逆变器直流侧增加1个由辅助开关、谐振电感和箝位电容组成的谐振支路,可以实现逆变器主开关和辅助开关的零电压开通,同时开关反并联二极管反向恢复电流得到抑制。逆变器主开关和辅助开关具有相同且固定的开关频率,主开关和辅助开关电压应力均等于逆变器直流母线电压。对逆变器的调制策略、软开关谐振过程进行了研究,分析了逆变器谐振参数的设计方法,设计了20 kW实验样机并完成了实验验证。

英文摘要：

A novel soft switching three-phase grid connected inverter was proposed.Through plug in a clamp branch,which consists of active switch,resonant inductor,and clamping capacitor into the dc link,zero voltage switching operation for all switching devices could be realized.Also the switch anti-parallel diode reverse recovery current was suppressed well.The switching voltage stress of all the power switch devices was equal to the DC link voltage.The modulation schemes and soft switching condition of this inverter were analyzed.The design guideline of the inverter was also analyzed.A 20？kW inverter prototype was built to verify the theory.