【作者】 高长征；

【导师】 李琳；

【作者基本信息】 华北电力大学（河北） ， 电工理论与新技术， 2009， 博士

【摘要】 本文针对电力系统电磁兼容问题所涉及的大型接地网性能分析、高压输电线路的无线电干扰水平分析以及高压换流站阀厅电磁环境分析等问题,结合国家自然科学基金项目重点研究了具有复杂金属线结构、考虑周围媒质环境以及需要进行多频点响应分析的复杂线结构电磁场问题的快速计算方法。通过与实验结果以及其他算法的结果进行比较,验证了本文各种方法的有效性。本文取得的主要研究成果如下:1.提出了一种快速计算低频情况下接地导体所产生的空间磁场的方法。在利用矩量法求解接地问题得到导体上电流分布的基础上提出了考虑周围土壤中泄漏电流分布的方法。应用该方法建立了快速计算接地网空间磁场的方法,不仅弥补了传统矩量法计算接地网磁场不精确的缺点,同时提供了优于有限元等方法的计算速度,为大型接地网的性能分析提供了高效计算工具。2.建立了考虑导体内阻特性的线结构积分方程法。选择分段三角基函数作为基函数和权函数建立了适合求解该积分方程的矩量法并通过等效变换技术简化了积分方程中矢量磁位的二阶求导计算过程。针对半无限大导电媒质空间情况应用复镜像法简化了矢量磁位的计算过程,提高了积分方程的求解速度。3.提出了特高压输电线路无线电干扰水平的分析方法。在确定无线电台(站)的允许背景噪声限值的基础上通过对无线电干扰水平特征进行分析提出了1000kV交流特高压输电线路对短波无线电台(站)的防护距离,为特高压工程建设提供了必要的参考依据。4.构建了一个基于多核处理器系统的PC集群。针对该集群在通讯和计算效能的特点,将接地网串行计算方法进行合理的并行化处理,开发了计算接地网的快速并行算法。5.提出了频域计算的分段自适应内插算法。通过智能的选择频率分段点避免了传统模型参数估计方法由于出现奇异点而无解的问题。开发了适合PC集群的并行分段自适应内插算法,极大提高了复杂电磁场问题在进行多频点响应计算时的速度。6.建立了超高压换流站阀厅的电磁骚扰天线计算模型。通过计算分析获得了±500kV换流站阀厅正常工作时的空间电磁场骚扰特征,提出了阀厅屏蔽结构应该具备的屏蔽效能以及抑制电磁骚扰的有效措施,为我国±500kV换流站的自主化设计提供了依据。更多还原

【Abstract】 The analysis of large grounding grids, radio interference of the transmission line and the electromagnetic environment of high voltage direct current (HVDC) converter station are paying much attention as their importance to the EMC problem. All of these problems can be treat as the electromagnetic field problems which have much conductor wires and the complex medium round them to be considered. And usually, many responses for different frequencies must be computed for these problems. Supported by the projects of Natural Science Foundation (50577019), in this thesis, the fast method to solve the problems above are researched and applied practical. Our methods are verified by comparing with the results tested and computed by other methods. The main innovative achievements are as follows:1. A fast approach to compute the magnetic field induced by the conductor under the ground at lower frequency is presented. As the leak currents in the soil are considered, the magnetic field obtained by this method is more accurate than the traditional moment method and also faster than the finite element method.2. A wire integral equation for imperfect conductor is set up. Using triangle basic function and galerkin method, combining the complex image method and integral transform method, the integral equation is solved fast by the moment method with the uniform lossy ground is considered.3. An approach for analysis of the radio interference level induced by EVAC transmission line is presented. And the protecting distance of the transmission line for the shortwave radio station is obtained which is practical for the EVAC project.4. A fast parallel method for analysis of large scale problems is developed based on the moment method and shows good speedup in a PC cluster built with multi-core CPU system.5. A self-adaptive MBPE method is presented. Combined with the parallel computing method, this method is very efficient for the large scale problem which many responses at different frequencies are needed.6. An antenna model for the valve hall in the HVDC converter station is setup to analyze its EM interference. Based on the results, the shielding effectiveness needed for the valve hall is represent and the useful shielding measures are given.更多还原