新型五电平混合级联逆变器的仿真研究

为减少传统混合级联逆变器所需的独立直流源，最近提出的一种新型混合级联逆变器。这种逆变器只需要一个直流源就可以实现三相五电平或七电平输出，缺点是，需采用一个三电平逆变单元。为此，文章提出了用两电平逆变单元代替三电平逆变单元构成另一种新型五电平混合级联逆变器，可使逆变器的电路结构得到简化。仿真证实了新型逆变器直流源以利用率下降并不显著，这种方法是可行的。

Simulation Study on a New Five-level Hybrid Cascaded Inverter

A new five/seven level hybrid cascaded inverter was proposed in recently to reduce the amount of separate DC sources oftraditional hybrid cascaded inverter. However, a three phase three level inverter cell required is the primary disadvantage of the new inverters.This disadvantage makes the main circuit complex and unbalances capacitor voltages. In this paper, anther new five level hybrid cascadedinverter is proposed to solve the disadvantage. This new inverter adopts traditional two level inverter cell to replace the foregoing three levelinverter cell. The simulation results based on MATLAB6.5/simulation verified that the decrease of utilization ratio of DC source is not evident.So the new inverter is feasible.