35kv变电所设计

河北农业大学本科毕业论文(设计)题目：任丘陈边村35KV降压变电站设计学院：机电工程学院专业班级：电气工程及其自动化0604班学号：2008212040105学生姓名：牛海涛指导教师姓名：李东明指导教师职称：讲师2010年6月01日1摘要变电站是电力系统的重要组成部分，它直接影响整个电力系统的安全与经济运行，是联系发电厂和用户的中间环节，起着变换和分配电能的作用。电气主接线是发电厂变电所的主要环节，电气主接线的拟定直接关系着全厂（所）电气设备的选择、配电装置的布置、继电保护和自动装置的确定，是变电站电气部分投资大小的决定性因素。本次设计建设一所35KV降压变电站，首先，根据主接线的经济可靠、运行灵活的要求选择各个电压等级的接线方式，在技术方面和经济方面进行比较，选取灵活的最优接线方式。其次进行短路电流计算，根据各短路点计算出各点短路稳态电流和短路冲击电流，对主要设备选择及校验，包括断路器、隔离开关、电流互感器、电压互感器、母线等作了初步的分析和选型。正确地选择电器是使电气主接线和配电装置达到安全，经济运行的重要条件。在进行电器选择时，应根据工程实际情况，在保证安全，可靠的前提下，积极而稳妥地采用新技术，并注意节省投资，选择合适的电器。最后，根据各电压等级的额定电压和最大长期工作电流，进行电气设备选择，然后进行校验并对二次部分进行预算编制！关键词：变电站.电气设备选择.短路电流计算.电气主接线.二次部分AbstractSubstationisanimportantcomponentofthepowersystem,whichdirectlyaffectthepowersystemsecurityandeconomicoperationofpowerplantsandcustomersarelinksinthemiddlepart,playaroleintransformationanddistributionofelectricenergy.Electricalpowerplantsubstationmainconnectionisthemainlinkinthedevelopmentofmainpowerisdirectlyrelatedtotheentireplant(the)selectionofelectricalequipment,powerdistributionequipmentlayout,relayprotectionandautomaticdevicestodetermine,istheelectricalpartofthesubstationInvestmentsizedeterminingfactor.Thedesignandconstructionofa35KVsubstationstep-down,firstofall,accordingtothemainterminaloftheeconomicandreliableoperationandflexibleaskedtoselectvariousvoltagelevelsofthewiring,technicalandeconomicaspectsinthecomparison,selecttheoptimalflexiblewiring.Thesimulationofshortcircuitcurrentcalculation,calculatedaccordingtothepointsshortpointsteady-statecurrentandshortcircuitshortcircuitsurgecurrent,majorequipmentselectionandcalibration,includingthecircuitbreaker,disconnectingswitch,currenttransformer,voltagetransformer,bus,andotherrelatedpreliminaryanalysisandselection.Thecorrectchoiceofappliancesistomakeelectricalmainwiringandpowerdistributionequipmentissafe,animportantconditionforeconomicoperation.When2makingelectricchoiceshouldbebasedonactualprojects,whileensuringsafeandreliableunderthepremiseofapositiveandsafeuseofnewtechnology,andpayattentiontosavinginvestment,selecttheappropriateappliances.Finally,accordingtothevoltageleveloftheratedvoltageandthemaximumlong-termoperatingcurrent,theelectricalequipmentselection,andthencheckthesecondpartandbudget!Keywords:substation.ElectricEquipmentSelection.Short-circuitcurrentcalculation.Electricalmainconnection.Thesecondpartofthe3目录第一节变电站总体说明........................................................................................................................51.1工程名称及地址..........................................................................................................................51.2自然情况......................................................................................................................................51.3建站的必要性..............................................................................................................................51.4自然条件......................................................................................................................................5第二节电器主接线设计方案................................................................................................................52.1电气一次部分..............................................................................................................................52.1.1电气一次部分主接线..........................................................................................................52.1.2平面设置..............................................................................................................................62.2主变压器容量的确定...................................................................................................................6第三节短路电流的计算......................................................................................................................103.1画出等效电路图，如图3-1所示.............................................................................................103.2求出各元件的等效电抗.............................................................................................................113.3各点的短路电流........................................................................................................................113.3.1系统在最大运行方式下的各点短路电流.........................................................................113.3.2最小运行方式下各点的短路电流.....................................................................................133.3.3冲击电流瞬时值：............................................................................................................143.3.4冲击电流有效值................................................................................................................15第四节电气设备的选择......................................................................................................................164.1断路器的选择............................................................................................................................164.1.135KV侧高压侧断路器的选择...........................................................................................164.1.210KV侧断路器的选择.........