低载波比下三电平中点电位平衡与谐波抑制策略  

Tri⁃level midpoint potential balance and harmonic suppression strategy under low carrier ratio

作　　者：庞松涵 刘剑[1] 吴奎奎 张红旗 PANG Songhan;LIU Jian;WU Kuikui;ZHANG Hongqi(School of Electrical and Electronic Engineering,Shandong University of Technology,Zibo 255000,China;Zhejiang Jiafeng Power Technology Co.,Ltd.,Jiaxing 314019,China;Shandong Shanbo Electric Machine Group Co.,Ltd.,Zibo 255299,China)

机构地区：[1]山东理工大学电气与电子工程学院,山东淄博255000 [2]浙江嘉丰动力科技有限公司,浙江嘉兴314019 [3]山东山博电机集团有限公司,山东淄博255299

出　　处：《现代电子技术》2025年第8期84-92,共9页Modern Electronics Technique

基　　金：山东省重点研发计划项目(2023JMRH0303)。

摘　　要：针对高速电机驱动场合下因低载波比导致的二极管中点钳位型三电平逆变器中点电位不平衡,进而引起输出电压畸变、谐波含量大等问题,提出一种改进的虚拟空间矢量调制方法来平衡中点电位。该方法以分压电容电位差为标准确定需要流出的中点电流平均值,从而分配正、负小矢量的作用时间,实现中点电位平衡控制。同时考虑低载波比场合下,因角度和采样延迟使虚拟空间中矢量失去中点电位漂移抑制作用,以及传统矢量区域划分在高调制比区间内(0.667<M<1)不使用虚拟小矢量的弊端,提出重新划分参考电压矢量区间并改变调制规则。仿真结果验证了所提方法对实现中点电位平衡与降低系统谐波含量的有效性。In allusion to the unbalanced midpoint potential in diode midpoint clamped tri-level inverters caused by low carrier ratio in high-speed motor drive scenarios,which leads to output voltage distortion and high harmonic content,a method of improved virtual space vector modulation is proposed to balance the midpoint potential.Based on the potential difference of the voltage divider capacitor,the average value of the midpoint current that needs to flow out is determined,so as to allocate the action time of the positive and negative virtual small vectors,and realize midpoint potential balance control.Considering the low carrier ratio situation,where the angle and sampling delay cause the vector in the virtual space to lose its midpoint potential drift suppression effect,and the drawbacks of traditional vector region partitioning in the high modulation ratio range(0.667<M<1)without using virtual small vectors,it is proposed to redefine the reference voltage vector region and change the modulation rule.The simulation results verify that the effectiveness of the proposed method for realizing the midpoint potential balance and the reduction of the harmonic content of the system.

关 键 词：高速永磁同步电机 三电平 低载波比 中点钳位型逆变器 空间矢量脉宽调制 电压平衡 

分 类 号：TN761-34[电子电信—电路与系统] TM351[电气工程—电机]