级联H桥多电平逆变器空间矢量调制与三角载波调制统一理论

The Unity Theory Between Space Vector and Triangular Carrier PWM Modulation Strategy in Cascaded H Bridge Multilevel Inverter

三角载波PWM(TCPWM)法和空间矢量PWM(SVPWM)法是级联H桥多电平逆变器主要的PWM调制方法。这两种调制方法存在一定的本质关系,但目前还没有很好地解决关于这两种方法的统一理论。针对这一问题,深入研究了多电平SVPWM序列与TCPWM的统一,通过在TCPWM调制波中叠加零序分量得到与SVPWM完全吻合的序列,最终推导出n电平含任意段数的SVPWM序列与TCPWM的统一,最后通过实验验证了该统一理论的正确性。

Triangular carrier pulse width modulation （TCPWM） method and the space vector pulse width modulation （SVPWM） method are the two main control methods used in cascaded H bridge multilevel converter. There is a certain relationship between this two modulation strategies, but this relationship has not been well studied so far. Thus, this paper studies the multi-level SVPWM modulation sequence and TCPWM unity. By superimposing zero-sequence onto TCPWM modulation wave, the same effect with the SVPWM modulation is achieved. At last, this paper deduces the unity of the SVPWM and TCPWM inn level with arbitrary number of segment sequences. Simulation and experimental results verify the correctness of the unified theory.