单开关辅助换流的箝位谐振直流环节逆变器

Clamping Resonant DC-link Inverter With Single Switch-assisted Commutation

为进一步提高逆变器的工作效率并简化其控制方式,提出一种新型箝位谐振直流环节软开关逆变器。箝位电路由箝位电源和二极管组成。辅助谐振电路由单独开关实现控制,当逆变器主开关需要切换时直流母线电压下降到零,逆变器的主开关与辅助开关均可实现软开关。根据各阶段等效电路,分别分析了逆变器的工作原理,组建一台2 kW实验样机。由实验结果知,该新型逆变器的主开关和辅助开关在操作过程中均可实现软开关,可有效降低开关损耗并提高效率。

A new clamped resonant DC-link soft-switching inverter is proposed to improve the efficiency of the inverter and simplify the control method.Clamping circuit is consisted of a clamping power and a diode.When main switches in the inverter needed operating, the DC-bus voltage decreased to zero via the single switch of the auxiliary resonance circuit.Then all main switching devices and auxiliary switching devices in the inverter are operated under soft-switching condition.The operation principle is designed based on the equivalent circuits at different operation stages.A 2 kW laboratory prototype is built.The experimental results demonstrated that all main switching devices and the single auxiliary switching device realized soft-switching during the period of operating, and it can effectively reduce switching loss and improve efficiency greatly.