级联型多电平逆变器的谐波分析及仿真研究

Harmonics analysis and simulation research of multi-cell-cascade multi-level inverter

利用数学推导分析了载波移相SPWM技术,对多单元级联型多电平逆变器进行了谐波分析,得到单相N单元级联型多电平逆变器输出电压的傅里叶表达式,同时对各单元间载波移相角相差π/N的控制方法进行了详细的数学分析,最后通过对单相三单元和四单元级联逆变器的仿真研究,得出结论并验证其正确性。

Carrier phase-shifted SPWM technique is derived from mathematical equation. The harmonics analysis of multi-cell-cascade multi-level inverter is made. Fourier expression of output voltage of single-phase N-cell-cascade multi-level inverters is given, at the same time, a control method that the angle of carrier phase-shifted is delayed one by one cell is mathematical analyzed in detail. Finally, the conclusion is reached and the correctness is proved, according to the simulation research of a single-phase three-cell-cascade and a four-cell-cascade inverter.