Integrated Active Filter for Differential-Mode Noise Suppression

This letter presents a novel integrated structure for electromagnetic interference (EMI) active filter. This approach integrates an active filter with a passive one to form a hybrid EMI filter. The chosen active filtering circuit is integrated on the printed board circuit embedding the integrated EMI choke. Theoretical and realization results show the integration compatibility between the active part and the passive part. Then, EMI measurements show that the proposed integrated hybrid filter can greatly reduce the noise at high and low frequencies while reducing the overall bulkiness.

I. Introduction

Switching power conversion systems leads to high conducted and radiated electromagnetic disturbances in a wide frequency band [1], [2]. These emissions may bring malfunctions to other electronic equipments used in sensitive applications. To protect the network and meet standards for electromagnetic interference (EMI) including the aeronautic standard “DO160F [150 kHz, 30 MHz],” an EMI filter is absolutely necessary.