对三电平变频器驱动电机的共模电压抑制的研究  

Study of common mode voltage suppression for induction motor driven by a three-level NPC converter

作　　者：钟玉林[1] 赵争鸣[1] 白华[1] 

机构地区：[1]清华大学电机系,电力系统国家重点实验室,北京100084

出　　处：《电工电能新技术》2008年第3期31-34,67,共5页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金重点资助项目(50737002)

摘　　要：降低和消除共模电压及共模干扰,在高压大功率电力电子变换器中具有重要意义。本文以一个三电平NPC变频器驱动的交流电机系统为研究对象,使用消除三次谐波式的特定谐波消除脉宽调制即SHEPWM(Selected Harmonics Elimination PWM)技术,从源头上消除变频器输出共模电压中的低频分量。而对所剩的高频部分共模谐波,使用共模滤波器进行滤除。定性和定量分析了差模滤波器参数不对称对共模电压的影响。实验证实了本文方案实用高效。Common mode （CM） voltage and its related interference have become prominent in high power converters. This paper aims to reduce the CM voltage of an induction motor driven by a three level （3L） NPC converter using the combination of both algorithm modification and hardware modification. The tripling frequency-eliminating SHEPWM （Selected Harmonics Elimination PWM） technique has been utilized to eliminate the low order 3-times harmonics of the converter. And then the rest of the CM voltage is attenuated by a well-designed CM filter. A detailed analysis of the effect of the differential mode inductance imbalance on CM voltage is given. Both experimental and simulation results show that a very low CM voltage at the motor terminal is obtained, which verify the validity of the scheme proposed in this paper.

关 键 词：共模滤波 特定谐波消除脉宽调制 三电平中点箝位式变频器 

分 类 号：TM714[电气工程—电力系统及自动化]