配电网覆盖面积大，面向广大用户进行电能分配，直接影响电力系统的供电可靠性。 由于配电线路耐雷水平普遍偏低，在雷击发生情况下，容易引发整条线路跳闸甚至断线 事故，给正常供电带来不利影响。近年来，随着阳江地区经济高速发展，工业用电、商 业用电和住宅居民用电显著增加，随之配电线路网架结构不断增多，各行业对供电可靠 和稳定的要求也相应提升。 阳江海陵地区为雷电活动频繁的区域，使得雷击引发的绝缘子闪络成为该地区配电 线路跳闸的主要原因。由于配电线路自身的特点，即耐雷水平普遍偏低，在雷击发生情 况下，容易引发整条线路跳闸甚至断线事故。另外电缆线路在城镇地区的推广应用，配 电线路不再是纯架空线路，故障发生类型多种多样，这给阳江海陵地区线路正常供电带 来极大的不利影响。而海陵配电线路由于分布面积广，传统的雷电防护措施应用到配电 线路上将是巨大的经济负担，加上线路维护工作的增加。因此，寻求简单有效且免维护 的雷电防护措施，对提升海陵配电线路供电可靠性和保障该地区正常供电具有重要作用。 本文首先对阳江地区的海陵配电线路网架结构、绝缘配合情况进行详细地分析，结 合当前该地区的雷害现状，提出防护雷击的改造意见和目标；然后通过具有典型代表性 配电线路的现场调研，结合理论分析，计算该地区配电线路的感应雷过电压平均水平， 从而比较几种配网防雷改造措施的优缺点；在此基础上，进一步分析“堵塞型”防雷措施 与“疏导型”防雷措施对该地区配电线路的适用性，提出防雷思路转换为采用并联间隙等 疏导型的防护；最后，针对海陵地区配电线路中性点运行方式、绝缘子的类型和自动重 合闸动作特性，分析并联间隙在海陵地区的工程实用性，得出并联间隙适用于阳江地区 10kV 海陵配电线路雷电防护的结论，为阳江配电网防雷措施的工程应用奠定了坚实的 基础。 关键词，配电线路；感应雷过电压；防雷措施；并联间隙II Abstract Distribution network supply for the customer directly. At the same time, the coverage area of distribution network is large. Therefore, the distribution network is one of the main components which affect the reliability of power system. Because the lightning withstand level of distribution feeders is low, the feeder will be tripped usually caused by the lightning. This decrease the reliability of the power system largely. In recent years, with the rapid economic development of Yangjiang city, industrial, commercial and residential electricity consumption increased significantly, increasing with the distribution line grid structure, the demand of reliability and stability of power system is also improved accordingly. Regional lightning activity in Yangjiang Hailing area is very frequent. Lightning flashover became the main reason for the region distribution line tripping. Due to low lightning withstand level of distribution feeder, lightning easily lead to tripping of the whole feeder easily, even with line break accident. Coupled with the application of cables in urban areas, distribution lines are no longer purely overhead lines. The fault types of feeders become more complex. It has a great adverse effect on the normal operation of Yangjiang grid. Because of the wide coverage area, the traditional lightning protection applied to the distribution feeders need a huge investment, besides the increase of line maintenance. Therefore, seeking a simple and effective lightning protection approach is important for the enhancement of the reliability of power system. In this thesis, the grid structure and insulation coordination of Yangjiang grid are analyzed in detail. Combined with the current situation of lightning in the area, the regional goals of the lightning protection reformation are put forward. With field investigation of the typical feeders, lightning induced voltage average are calculated theoretically. Several distribution network renovation of lightning protections are compared both of the advantages and disadvantages. On this basis, the thesis analyzes the application of two types of lightning protections, and puts forward the use of parallel gap. By considering the neutral point operation mode, insulator type and automatic recloser in the distribution network, the parallel gap is testified as an effective lightning protection for Hailing area. The studying work of the thesis is very useful for the lightning protection for the distribution network of Yangjiang city. Key Words: Distribution Lines; Lightning Induced Over-voltage; Lightning Protection Measures; Parallel GapsIII 目录 摘要.............................................................................................................................................I Abstract .................................................................................................................................... II 第一章 绪论..............................................................................................................................1 1.1 报告的目的和意义 ....................................................................................................... 1 1.2 国内外研究水平的现状和发展趋势 .......................................................................... 2 1.3 报告的主要工作 ........................................................................................................... 4 第二章 海陵配电网架空线路的特征分析..............................................................................6 2.1 引言 .............................................................................................................................. 6 2.2 海陵的地理位置与雷电特征 ...................................................................................... 6 2.3 海陵配电网架空线路的网架结构、绝缘配合分析 .................................................. 9 2.3.1 海陵配电网架空线路的网架结构 ..................................................................... 9 2.3.2 海陵配电网架空线路绝缘配合 ....................................................................... 10 2.4 海陵配电网雷害故障现状分析 ................................................................................ 12 2.5 本章小结 ..................................................................................................................... 13 第三章 海陵配网架空线路感应雷过电压理论计算和防护措施比较 ...............................14 3.1 引言 ............................................................................................................................ 14 3.2 感应过电压形成机理 ................................................................................................. 14 3.3 感应雷过电压计算 ..................................................................................................... 15 3.3.1 感应雷过电压计算模型 .................................................................................. 15 3.3.2 感应雷过电压计算方法与结果分析 ............................................................... 18 3.4 海陵配电网防雷改造建议 ......................................................................................... 21 3.5 海陵地区雷电防护措施比较分析 ............................................................................. 22 3.6 本章小结 .................................................................................................................... 28 第四章 中性点接地方式和自动重合闸配置情况对并联间隙装置动作特性分析.........29 4.1 引言 ............................................................................................................................ 29 4.2 配网架空线路中性点接地方式下线路单相短路电流分析 .................................... 29 4.2.1 中性点经消弧线圈接地适用性分析 .............................................................. 30 4.2.2 海陵配网架空线路中性点接地方式选择 ...................................................... 30IV 4.2.3 单相短路电流计算 .......................................................................................... 31 4.3 配网架空线路自动重合闸特性 ................................................................................ 34 4.4 自动重合闸装置选择性投运 ..................................................................................... 34 4.4.1 并联间隙装置与线路继电保护整定配合分析 .............................................. 35 4.4.2 单相对地短路灭弧特性分析 .......................................................................... 36 4.5 本章小结 ..................................................................................................................... 37 第五章 海陵地区配电线路并联间隙适用性与其配置原则分析 .......................................38 5.1 海陵配网架空线路绝缘子耐雷水平分析 ................................................................. 38 5.1.1 海陵配网绝缘子形式 ...................................................................................... 38 5.1.2 几种形式绝缘子耐雷特性计算分析 .............................................................. 40 5.2 并联间隙空气距离分析 ............................................................................................ 42 5.3 操作过电压分析 ........................................................................................................ 42 5.4 并联间隙的保护距离 ................................................................................................ 43 5.5 并联间隙结构设计、安装 ........................................................................................ 45 5.6 本章小结 .................................................................................................................... 47 结论..........................................................................................................................................48