新型单相全桥无源软开关逆变器

Novel Single-Phase Full-Bridge Passive Soft-Switching Inverter

为改善单相全桥逆变器的运行效率,设计出了一种新型单相全桥无源软开关逆变器,在每个开关周期的换流过程中,利用逆变器的低损耗辅助谐振电路,使开关器件实现软切换以节约电能.辅助谐振电路只含有电感、电容和二极管等无源器件,不会使逆变器的控制变复杂.此外,在逆变器处于死区状态下,负载电流可通过辅助电路进行续流,减小了死区状态对逆变器输出电流波形的不利影响.文中分析了电路的工作过程,在功率为3kW的单相样机上的实验结果表明开关器件能实现软开关,逆变器输出电流波形的畸变率得到了改善.因此,该拓扑结构对于研发高性能单相全桥逆变器具有重要参考价值.

A topology of novel single-phase full-bridge passive soft-switching inverter is proposed to improve conversion efficiency of the single-phase full-bridge inverter.During the commutation process of each switching cycle,the low-loss auxiliary resonant circuit of the inverter is used to save energy.There are some passive devices such as inductor,capacitor and diode,which cannot complicate the control strategy of the inverter.In addition,freewheeling of load current can be realized via the auxiliary circuit and the distortion ratio of output current waveforms of the inverter is reduced when the inverter is in the dead state.The operation process of the circuit is analyzed.The experiment is carried out on a 3 kW one-phase laboratory prototype.Experimental results verify that the switching devices of the inverter can achieve soft-switching and the distortion ratio of output current waveform of the inverter is improved.Therefore,the topology has an important reference value for the research and development of high performance single-phase full-bridge inverter.