110kV牵引变电所防雷接地的设计

兰州交通大学毕业设计（论文）1摘要雷电具有很强的危害性，因此应该重视牵引变电所雷电的防护。本文讲述了雷电、雷电压和雷电流的形成过程,并给出了雷电参数，阐述了防雷装置如避雷针、避雷器的防雷原理以及保护范围，给出了直击雷和感应雷的防护方案，介绍了目前我国牵引变电所防雷接地设计中常用的几种措施，如：合理选择牵引变电所修建的地理位置，架设避雷针、敷设接地网，在进线段装设避雷器，同时对几种防雷措施进行了深入的论述和定量的计算分析。基于常用的防雷接地的设计方法，对平北站110kV牵引变电所进行了详细的防雷接地设计。设计中，结合当地现状，综合考虑了气候、地形、环境等多种因素，给出了较好的防雷接地保护方案。通过对牵引变电所的防雷接地设计，全面剖析了电力系统中如何提高牵引变电所的防雷水平，从而有效地降低牵引变电所的雷击事故，减少雷电对电网安全运行的影响。最后绘制了平北接地网的平面设计图。关键词：牵引变电所；防雷接地；雷电放电；雷电流兰州交通大学毕业设计（论文）2AbstractThelightninghasverystrongharmfulness,soweshouldpayattentiontodrawingtheshelterofthelightningoftransformersubstation.Thistexttellstheformingprocessthatthelightning,thelightningvoltageandcurrent,providethelightningparameter.Atthesametime,itexpoundsthelightingprotectingprinciplesandprotectingscopesoflightingprotectingdevises,suchasthelightningrod,thelightingarrester.Itprovidestheshelterschemeofreactinglightingandattackinglightingdirectly,andhasrecommendedseveralkindsofthedailymethodwhichisduringthedesignoflightingprotectingandgroundinginthetransformersubstationatpresent,forinstance:ToChoosethegeographicalpositionwheretobuiltthetransformersubstation,erectthelightningrod,laytheearthingnetwork,installthelightingarresteronthestockoflinesegment.Itcarriesonexpositionandquantitativecomputationalanalysistoseveralkindsoflightingprotectingmeasuressrespectivelyalso.Onthebasisoflightningprotectingandgrounding’sdesignmethodcommonlyused,itdesignslightningprotectingandgroundingonthe110kVPingBeitransformersubstation.Inthedesign,combinesthelocalcurrentsituation,hasconsideredmanykindsoffactorssuchastheclimate,topography,andenvironmentsynthetically,providesbetterprogramsoflightningprotectingandgrounding.Throughthedesignsoflightingprotectingandgroundingoftransformersubstation,analyzinghowtoimprovetheleveloflightingprotectingofthetransformersubstationcompletelyinpowersystem,thusreducetheaccidentoflightningstrikingeffectively,andtheimpactonsafeoperationoftheelectricwire.DrewtheleveldesigndrawingofthePingBeiearthingnetworkfinally.Keyword:Thetransformersubstation;Lightningprotectingandgrounding;Lightningdischarge;Lightningcurrent.兰州交通大学毕业设计（论文）1目录第一章前言........................................................................................................................1一、牵引变电所防雷接地的必要性............................................................................1二、防雷接地的发展概况............................................................................................2第二章雷电参数及防雷装置................................................................................................3一、雷电放电................................................................................................................3二、雷电参数................................................................................................................3（一）雷击时的等值电路........................................................................................3（二）雷电流............................................................................................................4（三）雷暴日与雷暴小时........................................................................................7（四）地面落雷密度................................................................................................7三、避雷针和避雷线....................................................................................................7（一）保护原理........................................................................................................7（二）保护范围........................................................................................................7四、避雷器..................................................................................................................11（一）避雷器的分类及比较..................................................................................12（二）阀式避雷器电气特性的基本参数..............................................................15第三章防雷接地..................................................................................................................17一、接地与防雷接地..................................................................................................17二、冲击电流流经接地装置入地时的基本现象......................................................17（一）土壤中的电位分布......................................................................................17（二）土壤中的电场强度......................................................................................18（三）接地装置的电感效应及利用率..................................................................18（四）防雷接地装置的形式及其电阻的算法......................................................19第四章平北站110kV牵引变电所防雷接地系统设计......................................................22一、平北站110kV牵引变电所及环境气象条件......................................................22二、平北站110kV牵引变电所的直击雷防护方案及计算......................................22（一）直击雷防护方案..........................................................................................22（二）避雷针的计算及其安装..............................................................................23三、平北站110kV牵引变电所感应雷的防护..........................................................26兰州交通大学毕业设计（论文）2（一）牵引变电所进线段保护.