基于二端口网络的三相逆变器传导共模EMI模型

Conducted Common-mode EMI Model Based on Two-port Network for Three-phase Inverter

以典型的三相四桥臂逆变器为对象,分析其输入侧和输出侧传导共模干扰路径。根据逆变器共模干扰回路的结构和特点,结合二端口理论提出一种逆变器共模EMI的预测模型。分析了该模型的物理意义,给出了模型中阻抗参数及独立电压源的测量计算方法。最后,改变逆变器的结构和运行工况后测量输入侧输出侧共模电流,预测结果和实验结果的对比验证了该模型的正确性。

A typical three-phase four-leg inverter is studied in order to investigate the conducted common-mode electromagnetic interference （EMI） loop at both the input and output sides of the inverter. A common-mode EMI model of the inverter based on the two-port theory is proposed according to the structure and characteristics of its common-mode interference loop. The physical definition of the model is analyzed. the method of the model parameters extraction and calculation is given out. Finally, the input and output side common-mode current is measured after changing the structure and operating condition of the inverter. The model is verified by the comparison between the prediction results and the experimental results.