Abstract: As to the issue of complex computation for three-lever inverter SVPWM algorithms in Cartesian coordinate system, a SVPWM optimization algorithm in 60 º coordinate system is proposed. This SVPWM algorithm discriminates the regional distribution of hexagonal sectors by the sign of reference vector coordinate, and mappings the reference vector from other sectors to sector I in 60 ºcoordinate system. It discriminates the regional distribution of vector in sector I, and gets the dwell time of base vectors by using algebraic operation. Thus it normalizes the region judgment and dwell time calculation in sector I. The algorithm can effectively reduce the calculation of SVPWM algorithm, and improve the inverter efficiency. The results show that the output of current and voltage in the coordinate system has the same performance as the ideal curve, and the neutral voltage is balanced, and the switching frequency and switching loss are reduced.

Key words: Three-lever inverter, SVPWM, non-orthogonal coordinate frame, normalization

摘要： 针对直角坐标系下三电平逆变器SVPWM算法计算复杂的问题，给出了一种60 º坐标系下SVPWM优化控制算法。该算法利用参考矢量坐标的符号判别所在六边形大扇区的分布，利用60 º坐标系下矢量旋转关系将其他扇区矢量映射至第I扇区。并利用代数运算确定参考矢量在第I扇区内小区域的分布及其基础矢量的作用时间，实现区域判别和基础矢量作用时间计算的归一化处理。该方法可以有效地降低SVPWM算法的计算量，提高逆变效率。实验结果表明，60 º坐标系的SVPWM控制算法输出电流、电压波形的性能与理想曲线一致，系统的中点电位平衡，噪声低，减少开关频率和开关损耗。

关键词: 三电平逆变器, 空间矢量脉宽调制, 非正交坐标系, 归一化