级联H桥型多电平逆变器的CPS-SPWM调制策略研究

Research on the CPS-SPWM Modulation Strategy Used in Multilevel Inverter Based on Cascade H-Bridge

针对级联H桥型多电平逆变器的载波相移正弦脉宽调制(CPS-SPWM)技术展开研究。介绍了双极性CPS-SPWM和单极倍频CPS-SPWM的调制原理;进行了数学分析;利用MATLAB进行了建模仿真,采用频谱分析法进行了对比分析。结果验证了所做数学分析的正确性,单极倍频CPS-SPWM调制策略比双极性CPS-SPWM调制策略更优越。

This paper presents the research on the carrier phase shifted sinusoidal pulse width modulation(CPS-SPWM)technology of the multilevel inverter based on cascade H-bridge. First,the principles of bipolar CPS-SPWM modulation and the uni-polar dual frequency CPS-SPWM modulation are introduced,and a mathematical analysis is made subsequently and then a Matlab simulation model of the multilevel inverter based on cascade H-bridge is built and the comparative analysis between these two strategies is made by adopting frequency spectrum analysis method. The results obtained show that the mathematical analysis is correct and the uni-polar dual frequency CPS-SPWM modulation is better than the bipolar CPS-SPWM modulation.