基于高通滤波器的电机驱动系统电磁干扰测试  

Electromagnetic Interference Test of Motor Driver System Based on High-pass Filter

作　　者：秦洋 周天翔 袁文琦 陈恒林[1] QIN Yang;ZHOU Tian-xiang;YUAN Wen-qi;CHEN Heng-lin(Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学,电气工程学院,浙江杭州310027 [2]中车青岛四方车辆研究所有限公司,山东青岛100084

出　　处：《电力电子技术》2021年第9期23-27,共5页Power Electronics

摘　　要：在电机驱动系统中,脉宽调制(PWM)技术会引起严重的共模(CM)干扰和差模(DM)干扰。为了分析系统电磁兼容的问题,提出了电机驱动系统端口测试的新方法。采用示波器配合电压探头和电流探头进行测试,对所得系统噪声的时域波形进行傅里叶变换后,即为端口噪声的低频分量。根据示波器垂直精度与高频底噪的对应关系,确定目标限值,并设计数字滤波器分析端口各频段时域波形,计算滤波电路所需要的插入损耗,进而完成高通滤波电路的设计,实现抑制低频段噪声幅值、减小示波器的高频底噪的功能。最后通过实测获取了频率0.1~30 MHz的CM电压、CM电流、DM电压、DM电流的频谱信息。Pulse width modulation(PWM) technology used in motor driver system causes serious common-mode(CM)interference and differential-mode(DM) interference.In order to analyze the electromagnetic compatibility of the system,a new test method for the port of motor driver system is proposed.An oscilloscope is used to perform testing with a voltage probe and a current probe,the time-domain waveform of the system noise is measured and Fourier transformed to obtain the low-frequency component of the port noise.According to the corresponding relationship between the vertical accuracy of the oscilloscope and the high-frequency noise floor,the target limit is determined.A digital filter is designed to analyze the time-domain waveform of each frequency band at the port,and the insertion loss required by the filter circuit is calculated.Furthermore,the design of the high-pass filter circuit is completed to achieve the functions of suppressing the low-frequency noise amplitude and reducing the high-frequency noise floor of the oscilloscope.Finally,the frequency spectrum information of CM voltage,CM current,DM voltage and DM current with frequencies from 0.1~30 MHz is obtained through actual measurement.

关 键 词：共模干扰 差模干扰 电机驱动系统 

分 类 号：TN972[电子电信—信号与信息处理]