一种具有直通电流抑制能力的低电压尖峰Y源逆变器

A shoot-through current suppressed Y-source inverter with low voltage spike

针对传统耦合电感型阻抗源逆变器存在直流链电压尖峰和直通电流过大的问题,提出一种具有直通电流抑制能力的低电压尖峰Y源逆变器。分析了所提拓扑在直通状态和非直通状态下的工作原理,并给出了一个开关周期内的主要波形。采用安秒和伏秒平衡原理,分别推导出关键器件的电压、电流应力。与改进型Y源逆变器对比,当绕组系数相同时,所提拓扑在相同的升压比下具有更小的直通占空比,增大了调制比范围,提高了直流链电压利用率,并能够降低直流链电压尖峰。而且,所提拓扑能够抑制直通电流的增大,相同直流链电压下需要更小的直通时间使其直通状态下的开关管导通损耗更小。最后,搭建240 W实验装置充分验证所提拓扑的先进性。

To solve the high DC-link voltage and shoot-through current in traditional coupled-inductor impedance-source inverters,a shoot-through current suppressed Y-source inverter with low voltage spike was proposed.The shoot-through and non-shoot-through operational modes were analyzed in detail and key waveforms were provided.By applying current-second and voltage-second integrated over a switching period,the voltage and current stresses of the key devices was derived.Compared with improved Y-source inverter,the proposed topology applies lower shoot-through ratio when considering same voltage gain and winding factor,which increases the modulation ratio range and improves the efficiency of DC-link voltage,and reduces DC-link voltage spikes.Moreover,it can suppress the increment of shoot-through current.When the DC-link voltage is the same,the proposed topology requires a smaller shoot-through time,resulting in a less conduction losses in shoot-through state.Finally,a 240 W prototype was built and experimental results verify the superiority of the proposed Y-source inverter.