多种Z源逆变器的性能对比与应用背景分析

Comparative Analysis of All Kinds of Z-source Inverters in Properties and Their Application Background

传统Z源逆变器具有升降压功能,逆变桥壁无需插入死区时间,可靠性高,但其较大的启动冲击电流、较高的稳态电容电压应力造成开关器件的损耗较大。此外,需采用大容量、大体积的电容器件方能支撑该稳态电容电压应力,进而增加了成本。针对传统Z源逆变器的缺点,改进型Z源逆变器、准Z源逆变器、增强型Z源逆变器和直通分离型Z源逆变器被相继提出,由于结构性能各异,这些拓扑虽在不同方面弥补了传统拓扑的不足,但各自仍存在一定程度的局限,难以择出较理想的拓扑结构。因此通过分析现存Z源逆变器的特点,综合考虑各种Z源拓扑在性能、经济以及应用背景等方面的优劣性,折中选出最优拓扑。最后运用MATLAB仿真软件验证相应理论分析的正确性。

Traditional Z-source inverters have the advantages which exist in the traditional inverter. With thefunction of buck and boost, it has higher reliability and dead time is not needed to insert into upper and lowerlegs in the inverter bridge. However, there are still many shortcomings, for example, inrush current at startup,lower boost ability and higher capacitor voltage stress, then, capacitors which have large capacity andvolume are needed to support the capacitor voltage stress during steady state. Aiming at the deficiencies oftraditional Z-source inverters, several improved Z-source topology structures are presented one after another,although they can correct imperfections of traditional Z-souce inverters in different aspects due to theirdifferent performances, they also remain many drawbacks more and less respectively and it is difficult tochoose the best. So, in this paper, the features of all kinds of existing Z-source inverters are analyzed. Then,considering several aspects of Z-source inverters including properties, economy and applications, the optimalZ-source inverter is selected. Last, the correctness of corresponding theories is verified using MATLAB.