摘要
为研究外部电磁能量通过贯通导体耦合对腔体内部屏蔽效能的影响,利用电磁仿真软件FEKO,从频域角度对腔体内部场进行了仿真研究,利用矢量网络分析仪、功率放大器、GTEM室和全向电场探头搭建实验系统进行了验证,并通过建立含贯通导体金属腔体电路模型进行了谐振频率定性分析。结果表明:仿真和实验的结果具有一致性;当加入贯通导体后,腔体的屏蔽效能减小,谐振频率降低。腔体屏蔽效能随着贯通导体数量的增多而减小,随着电场极化方向与贯通导体夹角增大而减小,在腔体谐振频率以下随着监测点到贯通导体位置增大3倍,屏蔽效能提高20 dB。屏蔽效能的谐振频点受贯通导体长度影响较大,随着贯通导体数量增多而减小,不随电场极化方向和监测点位置变化而改变。为了改善含贯通导体金属腔体的屏蔽效能,应注意引入贯通导体后产生的新谐振频点,以及在这些频点上的屏蔽效能极小值,敏感电路应远离贯通导体放置。
To study effect of external electromagnetic energy coupling onto penetrative conductor on the internal shielding effectiveness （SE） of enclosure, we used FEKO to simulate the field inside the enclosure in frequency domain, and veri- fied the results through experiments conducted on an experimental system comprised of a vector network analyzer, power amplifiers, a GTEM chamber and omnidirectional electric field probes. We also built a circuit model of metal enclosure with penetrative conductor to analyze the enclosure＇s resonant frequency. Results show that simulation and experimental results are consistent. Adding penetrative conductor to an enclosure lowers its SE and resonant frequency. The SE de- creases with increasing the amount of penetrative conductors as well as the angle between the polarization direction of electromagnetic wave and the penetrative conductor. When the frequency is below its resonant value, increasing the dis- tance from the observation point to the penetrative conductor by 3 times will increase the SE by about 20 dB. The resonant frequency is influenced by the length of penetrating conductor significantly, and it decreases with the increasing the amount of penetrative conductors, but barely influenced by the angle and distance mentioned above. In order to im- prove the SE of enclosure with penetrating conductors, the resonant frequencies and the minimal SE at these frequencies influenced by the length of penetrating conductor should be concerned; meanwhile the sensitive circuits should be away from the penetrating conductors.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第9期2842-2848,共7页
High Voltage Engineering
基金
国家安全重大基础研究发展计划(973计划)(6131380301)~~
关键词
贯通导体
金属腔体
屏蔽效能
电磁兼容
电磁干扰
电磁耦合
penetrative conductor
metal enclosure
shielding effectiveness
electromagnetic compatibility
electromag-netic interference
electromagnetic coupling
