電源系統中，EMI 濾波器是抑制電磁干擾的重要部件，但是其高頻性能受限于元器件的寄生效應。本文針對差模濾波電容，設計一種PCB 耦合線圈消除其寄生電感，以此改善電容器濾波性能。首先，分析了濾波電容器寄生電感的消除原理；提出了一種繞制PCB 電感線圈的新方法，建立了PCB 電感器3D 有限元模型，基于以上分析，給出了適合消除電容器寄生電感的PCB 耦合電感器的設計步驟；最后，通過實驗驗證了本文設計方法的正確性與有效性。
Abstract：In power applications, the EMI filters which high frequency performance suffers from the parasitic parameters of passive components are important for attenuating electrical ripple, and eliminating electromagnetic interference. A sort of PCB coupled inductor is designed to effectively nullify the parasitic of differential-mode capacitors for EMI filters in this paper, thereby improving its high-frequency filtering performance. The principle of eliminating parasitic inductance is firstly analyzed. A new technique to coiling PCB windings is introduced, and the 3D finite element model of PCB inductor is built.The designing rules of PCB inductor for the applications to eliminating parasitic inductance is summed up based on coiling and calculating. Finally, the design of such PCB windings for inductance cancellation is explored and applicable designing rules experimentally validated.