大区域环境中强电磁脉冲与输电线耦合的高效混合方法研究

In large scale environment, the interaction process is very complex when the intense electromagnetic pulse is being influenced by the terrain profile and its electromagnetic parameters, thus it is very difficult to analyze the coupling effects with the long-range transmission line, which is unendurable to simulate via full-wave method. What’s more, the implementation height of the outdoor transmission lines is much higher than the limitation of the traditional transmission line (TL) theory. In order to solve those problems, an efficient time-domain hybrid algorithm is proposed to analyze the coupling effects between the intense electromagnetic pulse and the transmission lines. .Firstly, the transmission line model is to be improved and is suitable for high implementation situation, and its time-domain solving method is proposed to improve the overall accuracy when it is used to calculate the terminal response. Secondly, the critical simulation technology for the three-dimensional transmission lines is to be analyzed, to simulate the coupling effects when the intense electromagnetic pulse interacts with the multi-group transmission lines. Finally, the hybrid time-domain algorithm combined with parabolic equation (PE) and improved transmission line (TL) is proposed, and it is capable to take the realistic environment into account, so as to realize the integrated model including the geometric environment and the transmission line..The research results of this program will provide theoretical guidance and technical supports for the electromagnetic protection and maintenance of the power supply for the electric power network or the railway traction network.

在大区域复杂环境中，强电磁脉冲受各种地表环境的影响，其作用于输电线的过程变得异常复杂，其耦合分析求解变得非常困难，耗费的计算资源已经变得不可忍受；同时，实际输电线架空高度较大，已经超出了传统传输线方程的适用范围。针对上述问题，本项目拟提出大区域环境中分析计算强电磁脉冲与输电线耦合作用的高效时域混合算法。构建适用于架高输电线的传输线时域求解模型，提高其求解精度，分析强电磁脉冲对输电线作用的过程和规律；研究适用于传输线立体架设结构的电磁耦合求解关键技术，实现强电磁脉冲作用于多组多导体结构传输线的耦合响应求解；在此基础上，研究抛物方程与改进传输线方程相结合的高效混合方法，既能考虑区域环境影响又能解决长距离输电线计算资源耗费巨大的问题，从而实现真实环境与长距离输电线的一体化建模和求解。本项目的研究将为电力电网和铁路牵引网的安全稳定供电、电磁防护等应用需求提供理论指导和技术支撑。

在大区域复杂环境中，强电磁脉冲受各种地表环境的影响，其作用于输电线的过程变得异常复杂，其耦合分析求解变得非常困难；同时，输电线网络结构具有特殊性，并且在特定环境条件的影响下会产生特定的变化，采用传统的传输线建模难以准确实现输电线网络结构的模拟。.针对以上问题，本项目采用扰动技术、互易定理、正则化方法等对特定环境下的传输线模型进行修改，实现了非均匀传输线、高空双线、高频传输线等特殊结构的场线耦合问题的分析；采用状态变量方程、分段线性递归卷积等技术结合传输线方程，实现了端接频变网络的架空线结构的电磁耦合求解；借助不等长多导体级联、电磁拓扑、矩阵束方法等完成了复杂输电线路网络的建模、雷电辐射场的快速评估及雷电感应电压的快速计算；之后，改善了时域抛物方程完成了大区域复杂地理环境中电磁波传播过程的模拟。在此基础上，将时域抛物方程与FDTD、传输线方程相结合实现了大区域环境中精细目标电磁干扰问题的有效评估，并研究了高阶的FDTD方法及其并行技术，加快了程序的计算效率。本项目的研究提出了多种特殊环境下传输线模型的改进方法，提供了复杂输电线网络的高效建模技术，明晰了大区域复杂地理环境中强电磁脉冲和输电线路耦合的作用过程及机理，可以为电力电网、铁路牵引网的安全稳定供电、电磁防护等需求提供理论指导。