基于BLT方程的内置介质板异型腔屏蔽效能  

The Shielding Effectiveness of Heterotypic Enclosures Embedded Dielectric Layers Based on the BLT Equation

作　　者：郝建红[1] 蒋璐行 钱思羊 Hao Jianhong;Jiang Luhang;Qian Siyang(School of Electrical and Electronic Engineering North China Electric Power University,Beijing 102206 China;China Power Construction Engineering Consulting Co.Ltd,Beijing 100120 China)

机构地区：[1]华北电力大学电气与电子工程学院,北京102206 [2]中国电力建设工程咨询有限公司,北京100120

出　　处：《电工技术学报》2020年第18期3791-3801,共11页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(61372050);中央高校基本科研业务费专项基金(2018QN013)资助项目。

摘　　要：金属腔体外部形状以及内部结构均会对腔体屏蔽效能造成影响。针对内置介质板的异型开孔金属腔体的特点,通过推导异型腔体非连续处等效电路的散射参数,基于电磁拓扑理论和BLT方程,建立平面波照射下凸面结构腔体和阶梯结构腔体屏蔽效能的解析模型,并研究了介质板的位置等对异型腔体屏蔽效能的影响。通过引入开孔位置系数和观测点位置系数,该解析模型可以处理任意位置开孔和任意位置观测点的情况。结果表明:介质板可以有效抑制异型腔体谐振,谐振点附近的屏蔽效能得到显著提高,但是对远离谐振点频域的屏蔽效能影响较小;不同谐振点处存在最佳介质板位置,使得在其取值区间内屏蔽效能达到最大。理论计算结果与全波仿真软件CST的结果有较好的一致性,证实了该文解析模型的有效性。相较于数值计算方法,该解析模型计算效率更高且占用内存更少,对异型腔体的屏蔽设计具有指导意义。The outer shape and inner structure will affect the shielding effectiveness(SE)of metallic enclosures.By deriving the scattering parameter of the equivalent circuit at the discontinuous position of the heterotypic enclosure,the analytical models for the SE of an enclosure with convex structure and an enclosure with stepped structure excited by a plane wave are established based on the electromagnetic topology theory and the BLT equation.The effects of the position of the dielectric layer on the SE of the heterotypic enclosure are then analyzed.The analytical model can be used to calculate the SE at any point in the enclosure with arbitrarily positioned aperture by introducing the coefficients of the aperture position and the observation point position.The results show that dielectric layer can effectively suppress the resonance of the heterotypic enclosure,which improves the SE for frequencies near the resonances while less affecting the SE for frequencies far away from the resonances.The optimal layer position exists at different resonance points,thus the SE reaches the maximum value within the interval of the layer position.The analytical results are in good agreement with those of the full-wave simulation software CST,which validates the efficiency of the analytical models.Compared with the numerical methods,the analytical model has higher efficiency and requires less memory,which has guiding significance for the shielding design of heterotypic enclosures.

关 键 词：屏蔽效能 电磁拓扑理论 BLT方程 异型腔体 介质板 

分 类 号：TM15[电气工程—电工理论与新技术] TM25[一般工业技术—材料科学与工程]