一种快速的多电平空间矢量调制算法

Fast Algorithm for Space Vector Modulation of Multilevel Inverter

针对多电平逆变器在空间矢量调制时出现的空间矢量定位困难和计算量大的问题,根据基本矢量在α′β′两相坐标平面的坐标都是整数的规律,得到了在α′β′两相坐标平面下对参考电压矢量进行逼近的算法,该算法只需要进行简单的四舍五入与加减运算,易于实现。最后通过对参考电压进行同步采样,得出了空间矢量调制算法在α′β′平面上收敛和在abc平面上收敛,并指出空间矢量调制算法的收敛性影响逆变器输出电压的次谐波。

The difficulty of making the appropriate vector selection in multi-level inverter is a lagrer of computation. Based on the rule that all the coordinate value of the basic vector is integral in α＇β＇ coordinate plane, an algorithm for approaching the reference vector in α＇β＇ coordinate plane was drawn out, which is easy to be realized by arithmetic and rounding operation. By synchronized sampling the reference vector, it is found that modulation algorithm is con vergent in α＇β＇ coordinate plane and abc coordinate plane and that can affect the sub harmonic component of multilevel inverter＇s output voltage.