基于多导体传输线理论的差模激励新型线束串扰模型研究

传统的线束串扰模型只是在系统内共模激励的基础上建立的, 没有考虑系统间差模激励下线束串扰的情况. 针对差模激励下系统独立回路间线束串扰的物理问题, 提出了一种基于多导体传输线理论的差模激励新型线束串扰的计算方法.该方法根据差模激励下线间的耦合机理, 利用传输线传播横向电磁模式得到新型三导体传输线寄生参数电路及数学矩阵模型, 通过镜像法以及诺埃曼公式推导出寄生参数的计算公式, 并在频域内得到新型线束串扰的链参数矩阵方程, 根据新型差模串扰模型始端、终端边界条件最终得到串扰电压的频域解.以差模激励下平行双线回路对其他回路受扰线的串扰为例, 通过仿真受扰线不同布置情况下的串扰电压, 得到了差模激励源的线束间串扰的物理规律, 即受扰线位于差模回路之间时所受的串扰要远大于位于回路外时所受的串扰, 并验证所提出的模型及方法可以计算不同频率差模激励引起的干扰. 利用解析的方法解决了线束串扰中差模激励下的导线串扰问题, 为实际中如大量导线的捆扎以及导线干扰的预测等电磁兼容问题提供了理论依据, 具有指导意义, 完善了多导体传输线理论在线束串扰中的应用.

New differential-mode-source cable bundle crosstalk model based on multiconductor transmission lines theory

The traditional cable bundle crosstalk model is established based on an intra-system common mode source, without considering the crosstalk of cable bundles stimulated by a differential-mode source between different systems. To solve the physical problem of crosstalk between independent circuit cable bundles which is stimulated by a differential-mode source, in this article we propose a new differential-mode source cable bundle crosstalk calculation method based on the multiconductor transmission line theory. According to the mechanism of the differential-mode-stimulated transmission line coupling, using this method we obtain a new three-conductor transmission line parasitic parameter circuit model and mathematic matrix model through using the transmission line propagating transverse electro magnetic mode. We deduce the parasitic parameter calculation formula by an image method and Neumann formula, and then obtain the new cable bundle crosstalk chain parameter array equations in frequency domain. By using the top and end boundary conditions of the new differential-mode cable bundle crosstalk model, we finally work out the crosstalk voltage in frequency domain. In this article, we take the crosstalk between differential-mode parallel double culprit cables and the victim cable from other independent circuit for example. By simulating the crosstalk voltage of victim cable in different position arrangements, we obtain the crosstalk physical law between cable bundles under the differential-mode source condition, that is, the crosstalk of the victim cable located between differential-mode circuits is much larger than that situated outside the differential-mode circuit. We can also verify that this model can be used to calculate the crosstalk caused by differential-mode source at different frequencies. In this article, we analytically calculate the crosstalk problems caused by differential-mode source cable bundles for the first time, which provides theoretical basis for solving some practical electromagnetic compatibility problems such as the bundling of a large quantity of wires and the predicting of cable bundle crosstalk. Therefore it perfects the application of multiconductor transmission line model to cable bundle crosstalk problem, and has strong guiding significance.