含短贯通导体的金属腔体电磁辐射耦合规律  

Coupling Law of Electromagnetic Irradiation to Metal Enclosure with Short Penetrative Wire

作　　者：李新峰[1,2] 魏光辉[2] 汪连栋 曾勇虎 韩慧 潘晓东[2] 

机构地区：[1]电子信息系统复杂电磁环境效应国家重点实验室,洛阳471003 [2]军械工程学院静电与电磁防护研究所,石家庄050003

出　　处：《高电压技术》2016年第3期987-993,共7页High Voltage Engineering

基　　金：国家安全重大基础研究发展计划(613138);预研项目(51333030101)~~

摘　　要：为研究含短贯通导体金属腔体在平面波辐射条件下内部电磁耦合规律,利用电磁数值计算软件CST建立了含短贯通导体金属腔体电磁辐射耦合模型,研究了加载短贯通导体对开孔金属腔体内部屏蔽效能的影响。并基于GHz横电磁波室(gigahertz transverse electromagnetic cell,GTEM)搭建了含短贯通导体金属腔体电磁耦合实验平台,对数值计算结果进行了实验验证。同时分析了平面波辐射条件下贯通导体长度、贯通导体半径、贯通孔尺寸、电场极化方向等参数对内部电磁耦合的影响规律,揭示了短贯通导体引入电磁干扰的耦合机理。结果表明:当屏蔽效能为40 d B的开孔腔体加载短贯通导体后,腔体内部屏蔽效能明显下降,屏蔽效能最小值达到-15.29 d B;腔体外部裸露贯通导体长度增大3 cm,腔体的屏蔽效能降低约4 d B;腔体内部贯通导体长度主要影响腔体的谐振频点;贯通导体长度不变而内外部分长度变化时,腔体屏蔽效能和谐振频点均发生变化;贯通孔尺寸增大,导致腔体内部屏蔽效能下降;测试点距离贯通导体越远,屏蔽效果越好;贯通导体半径能够影响屏蔽效能和腔体谐振频点;腔体壁厚度每增加0.3 cm,谐振频率增大约8 MHz;平行于贯通导体的电场分量越大,腔体屏蔽效能越差。In order to study the coupling law of electromagnetic irradiation to enclosure with short penetrative wire, we established a coupling model of one enclosure with a short penetrative wire in CST. We also established a corresponding experiment platform based on the Gigahertz transverse electromagnetic（GTEM） chamber to verify the calculated results through experiments. Moreover, we analyzed influences of penetrative wire＇s length and radius, size of aperture, the polarization direction of electric field on the electromagnetic coupling in enclosure with short penetrative wire under the condition of planar wave radiation, and revealed the coupling mechanism of penetrative wire induced electromagnetic interference. The results indicate that shielding effectiveness（SE） of an enclosure with aperture decreases from 40 d B to-15.29 d B when a wire is put in aperture. The SE of enclosure decreases by 4 d B when the length of external penetrative wire increases by 3 cm, while the resonance frequency is mainly influenced by the length of the penetrative wire inside the enclosure. When the length of a wire maintains a certain value but its length inside and outside the enclosure changes, both SE and resonance frequency change. The SE of enclosure descends when the aperture gets bigger. The SE of enclosure increases with increasing the distance from test point to penetrative wire. The radius of penetrative wire affects both SE and resonance frequency. The resonance frequency of enclosure increases by 8 MHz when the thickness of enclosure wall increases by every 0.3 cm. The higher the parallel electric field value is, the worse the enclosure＇s SE will be.

关 键 词：贯通导体 开孔腔体 参数 GTEM室 屏蔽效能 耦合机理 

分 类 号：TN03[电子电信—物理电子学]