本设计是机械厂机加工车间的低压配电系统及车间变电所供电系统。本文首先进行了负荷计算，根据功率因数的要求在低压母线侧进行无功补偿，进而确定对主变器容量、台数，从经济和可靠性出发确定主接线方案。其次，通过短路电流计算出最大运行方式和最小运行方式下的短路电流，确定导线型号及各种电气设备。最后根据本厂对继电保护要求，确定相关的保护方案和二次回路方案。本设计采用需用系数法进行负荷计算，无功功率补偿采用低压侧电容并联补偿方法，这种方法能补偿低压侧以前的无功功率、经济效益比较好。根据机械加工车间用电特点和需求，主接线方案采用了高压侧无母线、低压侧单母线分段的主接线方案。根据干式变压器与油浸变压器在经济和安装条件对比，选择两台SC9-500/10系列干式变压器。在仔细研究各负荷的实际数据，并严格按照国家规定，依照以上设计步骤设计本供电系统设计方案，以到达提高生产效益的目的。关键词：低压配电系统；负荷计算；主接线；变电所；短路计算AbstractThisdesignisthefactorymachiningworkshopoflowvoltagedistributionsystemandworkshopsubstationpowersupplysystem.Thispaperconductedaloadcalculation,accordingtotherequirementsofpowerfactorinthelow-pressuresideofthebusreactivepowercompensation,andtodeterminethecapacityofthetransformerdevice,thenumberofunits,startingfromtheeconomicandreliabilitytodeterminethemainterminalprogram.Secondly,calculatethemaximumshortcircuitcurrentoperationmodeandminimumoperatingmodeoftheshortcircuitcurrenttodeterminethewiretypeandvarietyofelectricalequipment.Finally,accordingtothefactoryonprotectionrequirements,identifyrelevantprogramsandsecondarycircuitprotectionprogram.Thisdesignusestheneedcoefficientmethodfortheloadcalculation,reactivepowercompensationcapacitorinparallelwithlow-pressuresideofthecompensationmethod,thismethodcancompensateforlow-voltagesideofthepreviousreactivepower,economicefficiencyisbetter.Accordingtomachineshopcharacteristicsandneedsofelectricity,themainconnectionschemesusingnon-bushighside,lowsideofthesingle-bussectionoftheMainWiring.Accordingtodry-typetransformersandoilimmersedtransformersandinstallationconditionsintheeconomycomparedtoselecttwoSC9-500/10seriesofdry-typetransformers.Onlythencarefullystudiesthefactorytheactualdata,strictlystipulatedaccordingtothecountry,andonlythenmaydesignaneconomyreliablepowersupplysystemthroughtheabovedesignprocedure,thusarrivestheenhancementproductionbenefitthegoal.Keywords:LowVoltageDistributionSystem;LoadCalculation;MainConnection;Substation;Shortcircuitcalculation目录1绪论..................................................................................................................................11.1设计背景、目的及意义........................................................................................11.2设计内容................................................................................................................11.3设计原则................................................................................................................12负荷计算及无功补偿......................................................................................................22.1负荷计算................................................................................................................22.1.1负荷计算的方法及其适用范围..................................................................22.1.2需用系数法..................................................................................................22.1.3负荷确定.....................
