A TECHNIQUE TO IMPROVE THE EMI REDUCTION PERFORMANCE OF COMMON-MODE INDUCTORS USED IN EMI FILTER CIRCUITS

摘要

In this paper, a technique to improve the EMI reductionrnperformance of common-mode (CM) inductors used inrnEMI filter circuit is proposed. By adding the extrawindingrnat the ground line, the conventional CM inductorrncan improve the CM EMI reduction performancerneffectively. The dot polarity of extra-winding is dividedrninto two cases: added up or subtracted the H-field insidernthe core of CM Inductor. The EMI redactor performancernof proposed concept is verified by the experiments. Fromrnthe experimental results, it shows the improvement of CMrnEMI reduction performance of H-field added comparingrnto the conventional and H-field subtracted CM inductors.