环形平面EMI滤波器差模电感的提取与实现

摘要

平面EMI滤波器是电力电子系统小型化、模块化和集成化的一条有效途径,其差模电感是由两个具有对称结构的共模电感产生的漏感实现.作为抑制EMI差模传导干扰噪声的重要部件,差模电感必须得到精确计算和设计.本文求解了应用于环形平面EMI滤波器中共模电感之间漏感计算的解析表达式,建立了漏感提取的数值计算模型,并通过计算与测量结果将两种方法进行了比较.在此基础上,分析了共模电感绕组主要结构尺寸对漏感值的影响,总结了设计中调整漏感值的途径.本文实现了该类漏感结构,实验结果说明建立的数值模型的精确性,调整漏感值措施的可行性,为平面滤波器差模电感的实现提供有益指导.%Planar EMI filter provides an effective approach for miniaturization, modularization and integration of power electronics system. Differential mode inductor in planar EMI filter is realized by the leakage inductance between common mode inductors. As the important role in restraining differential mode noise of conducted EMI, differential mode inductance has to be precisely calculated and designed. Analysis equation for differential mode inductance in annular EMI filter is solved and its numerical model is established in this paper. The comparison of these two kinds of computing methods is then given by calculated results and measurement. Besides, major factors which have great influence on leakage inductance are analyzed and approaches of adjusting leakage inductance are summarized. Based on theoretical analysis and experiment, the numerical model of calculating leakage inductance is revealed to be precise, and approaches of adjusting leakage inductance are confirmed to be effective. The theoretical system in this paper provides a beneficial instruction for realization of planar EMI filter's differential mode inductor.