Common-mode voltage suppression method

The invention provides a common-mode voltage suppression method, which adopts a modulation strategy for switching a common-mode voltage suppression strategy according to a modulation ratio, eliminates a common-mode peak caused by introduction of dead time, and can reduce the common-mode voltage of a permanent magnet synchronous motor system from # imgabs0 # to # imgabs1 #. According to the method, different vector synthesis modes are selected under different modulation degrees of the system, the output current quality of the system and # imgabs2 are further optimized, and the linear modulation range of the system is widened. The algorithm does not need to change a hardware topological structure, the calculation amount is small, and programming implementation is easy. 本发明提供一种共模电压抑制方法，采用了一种根据调制比对共模电压抑制策略进行切换的调制策略，并消除了针对引入死区时间所造成的共模尖峰，可以将永磁同步电机系统的共模电压从#imgabs0#降为#imgabs1#。本方法通过在系统的不同调制度下选用不同的矢量合成方式，进一步优化了系统的输出电流质量和#imgabs2#，拓宽了系统的线性调制范围。该算法无需改变硬件拓扑结构，计算量较小且易于编程实现。