高导铁氧体宽频高阻抗共模电感设计

Design of high-permeability ferrite-core common mode choke with wide-band and high impedance

通过对共模电感工作原理及特点的分析,提出了两种优化高导铁氧体共模电感阻抗-频率特性的设计方法:其中环形高导铁氧体单层绕线设计极大地降低了绕组寄生电容,提高了谐振频率,从而改善了阻抗—频率特性;使用FT型高导铁氧体磁芯与扁铜线单层立绕设计还可以降低磁芯与绕组之间的寄生电容,提高了谐振频率,从而改善阻抗—频率特性。

According to analyzing of the mechanism and features of common mode choke,two kinds of solution were proposed to optimize the frequency dependence of impedance of high-permeability ferrite-core common mode choke:single layer winding of ring core and single layer copper edgewise winding of FT-type core.The turn-to-turn capacitances between turns of adjacent layers decrease and the resonance frequency increases for former structure,and resultantly the frequency dependence of impedance is improved.For the latter,or the design of edgewise winding of FT-Type core,the turn-to-core capacitance also decreases and the resonance frequency increases,and the choke has excellent impedance performance in a wide frequency range.