一种新型的三电平逆变器中点电压平衡控制策略

A New Control Strategy for the Neutral Point Potential Balance for the 3-Level Inverter

三电平逆变器中直流侧中点电容电压平衡问题直接影响着逆变器及其电机调速系统的可靠性。文章首先介绍了三电平逆变器的SVPWM算法;在此基础上,提出采用动态调整正负空间电压矢量作用时间的方法来实现中点电位平衡,并作了具体的阐述。理论分析和仿真结果表明,此方法能有效地平衡三电平逆变器的中点电压。

The neutral point potential balance is one of the key aspects that affects the realiability of a 3-level inverter and its speed-adjusting system.This paper firstly introduces the SVPWM algorism,then based on it presents a method that can balance the neutral point potential by dynamic adjustment of operating time of the positive and negative space voltage vectors,and describes it.The result shows that this method can effectively balance the neutral voltage of 3-level inverter through theoretical analysis and simulation.