基于EMI滤波器的逆变器传导电磁干扰的抑制

Suppression of EMI Conducted in PWM Inverter Based on EMI Filter

由于干扰源和负载阻抗对EMI滤波器的滤波效果有很大影响,根据PWM逆变器的传导干扰源和负载阻抗的特点,在已有的EMI滤波器结构选取原则的基础上,提出了一种设计EMI滤波器的方法,使得EMI噪声到达LISN时,经过了最大限度的衰减,给出了共模和差模干扰的设计实例,实验结果表明,该方法简单、有效。

The noise source and load impedance have large effects on the insertion loss of EMI filter. According to the characteristic of noise source conducted in PWM inverter and load impedance, a method of designing EMI filter was proposed on the basis of existent designing principle of EMI filter, which simplifies the design of EMI filter. The EMI noises in LISN are attenuated to the most extent using the design principle. Practical design examples including CM and DM EMI filter are given. The experimental results indicate the EMI filter design method is simple and effective.