电磁干扰的非规则路径耦合机理及解析模型研究

Today the electromagnetic coupling analysis for irregular apertures and cables with complex sizes (large on one dimension while small on the other dimension) is a big challenge in EMC field. For structures with complex sizes, the numerical methods is not applicable, which consumes too much sources and times due to the extremely fine meshing. The classic analytical methods for the coupling of apertures and cables, which is derived from the Maxwell’s equations and boundary conditions, are much faster. However, the derivations of the analytical methods are usually complicated. Furthermore, the analytical methods are only effective for structures with specific regular shapes and could hardly be applied to irregular structures. To deal with this problem, a novel analytical method is presented by analyzing the mechanism of electromagnetic coupling and improving the existing methods.

当前，对于复杂电尺寸（即某一维电尺寸很大、而另一维电尺寸很小）的非规则孔缝、线缆，其电磁耦合计算问题历来是电磁兼容领域的难点。对于复杂电尺寸结构，如果采用数值算法计算，由于计算网格划分过于细密，需要耗费巨量的计算机资源，以及较长的计算时间，解决问题的实时性很差。而经典电磁解析法从麦克斯韦方程组和边界条件出发，经严格数学推导得到孔缝、线缆耦合解析式，具有运算速度快的特点。但经典电磁解析法推导分析过程中需应用大量电磁理论和数学知识，一般比较繁琐，且只适用于极少数规则几何结构，难以解决非规则孔缝和线缆问题。本项目针对这一问题，从分析非规则路径电磁耦合机理出发，在现有各类算法的基础上进行改进、创新，建立新型的电磁解析算法，从而解决这一电磁计算领域难题。

针对电磁干扰的非规则路径耦合机理不明、解析电磁结果难以获取的难题，本研究以获得非规则孔缝和线缆电磁解析解（或半解析解）为主要目的，从分析非规则路径电磁耦合机理出发，分别研究了：1）任意形状孔缝的电磁耦合机理及耦合系数解析计算模型，获得了电大尺寸矩形、圆柱形金属机箱某一侧面的任意位置上开有一个任意形状的狭长孔缝条件下的机箱内任意位置电场强度的频域快速计算方法和信号波形的时域快速计算方法；2）弯曲细长线缆的电磁耦合机理及耦合系数解析计算模型，获得了弯曲细长线缆终端电压时域和频域快速求解算法。研究成果已应用到飞机系统屏蔽特性与谐振特性分析研究中，支撑了国产武器装备的电磁兼容设计与分析。