A layout method of passive EMI filter

For suppressing of the conducted electromagnetic interference (EMI), passive EMI filter (PEF) is the most widely applied technique at present. The near-field coupling due to PEF passive components layout has great influence on filtering performance. Currently, the layout of PEF components completely dependents on the experience of EMC engineer. However, there is a lack in systematic design method and scientific design basis. For this reason, in this paper, an optimization design method of PEF layout is presented. The method is based on distribution rule and mechanism of near-field coupling of PEF components, which can decrease volume and improve the filtering performance of PEF. Finally, theoretical analysis and experimental results show that the presented method of PEF layout can effectively improves the filtering performance of PEF.