Coupling inductor models for EMI filters

This paper analyzes the electrical parameters of differential-mode (DM) and common-mode (CM) inductors used in EMI filters. To design an EMI filter, it is necessary to identify the various parameters of the passive elements: inductors and capacitors. Because of their major impact on filter efficiency, these elements must be identified with accuracy. In this study, a high frequency model of coupled inductors is proposed. Simulation results of the proposed model are compared to the experimental data obtained using a specific experimental setup. These results made it possible to validate the filter model in frequency range varying from 9 kHz to 30 MHz. The proposed high frequency coupled inductors model will be very helpful for EMI filter optimization design.