220千伏变电站 220千伏变电站防雷保护设计及计算.doc

220千伏变电站 220千伏变电站防雷保护设计及计算 原始资料及要求 220千伏变电站防雷保护设计及计算 摘 要 雷电是大自然最宏伟壮观的气体放电现象。雷电放电所产生的雷电流高达数十甚至数百千安，从而会引起巨大的电磁效应，机械效应和热效应。变电站作为电力系统的重要组成部分，很容易产生事故，特别是，近年来随着经济的发展，对于电力系统的稳定性有很高的要求。因此，要求有可靠的防雷措施。 本设计是针对220kV变电站的防雷保护进行设计及计算，根据变电站雷击事故来源不同，提出了相应的解决方案： 1、雷电直击变电站设备和线路，解决方法：采用四支等高避雷针分别安装在变电站的两侧墙上，距四个墙角的距离均为20m，针高33.77m。接地装置选用五根长2.5米，外径为0.050米，壁厚4毫米，理论重量为 4.54kg/m的钢管。 2、沿线路传入变电站的雷电波，解决方法： 设计入侵波保护。经计算220kV侧及110kV侧都采用2km的进线段，其中220kV侧a?1.50kv/m，110kV侧a?0.82kv/m。 3、由于输电线路是电力系统的大动脉，担负着将发电厂和经过变电所后的电力输送到各地区用电中心的重任。所以，对其也应该进行保护。对输电线路防雷性能计算。其结果为：110kV线路平原雷击跳闸率为0.723，山区雷击跳闸率为1.116；220kV线路平原雷击跳闸率为0.2652，山区雷击跳闸率为1.295。 关键词：防雷,接地装置,入侵波,雷击跳闸率 THE AVOIDING FORM THUNDER STOKE AND I COUNT OF POWER SYSTEM ABSTRACT The thunder is to be turned on electricity to the building of the ground and the nature of the earth by the cloud(take the bank of clouds of the electricity) of, it will break to the building or equipments creation severity.Thunder is the greatest view in the world . The power flow flow made by thunder will be about tens, even hundreds A,change relatively impact.Power system have become more reliability . So we need successful protection. It has two aspects about source of transformer thunder stoke , we make the solution following it: pointed the thunder stoke directing. As designing four lighting rob in the wall of the station.I choose four same lighting rob is m to protect . The join-ground devices choose 5 steel tubes , the length of which is 2.5 m,the diameter of which is 50 mm , the thickness of steel tube outer is 4 mm and the theory weight is 4.54 kg/m. 2．Thunder electric wave along the line . Avoid form attacking wave design . By counting 220kv side and 110kv side all use 2 km,there into 110kv side a is 0.82kv/m, and 220kv side a is 1.50km/m 3．Because the lines are important for the system . Will transmit the power made by the station to the local of 110kv line is 0.723 on plain area; the thunder stoke ratio of 110kv line is 1.116 on mountains area. Th