供电系统毕业设计

I摘要随着科技的不断发展和社会的全面进步，人民生活水平不断提高，电力能源已深入到了人们的日常生活和工作中去，对电力工业的发展极其相关问题的研究层出不穷。基于目前我国电力工业飞速发展的现状，结合新型工厂发展的实际要求，倡导“安全、高效、节能”的方针，集变电、配电、照明、自动控制与调节、建筑防雷与保护、电脑设备管理于一体的现代化工厂供用电系统。本设计在充分调查工厂符合设备的情况下，采用需要系数法计算全厂电力负荷，据此与电业部门签订协议，确定供电等级。按照工厂的实际要求进行系统的无功补偿，确定视在计算负荷，将全厂电力负荷按其工作要求的不同分为不同负荷类别，根据工厂发展和规划要求，选择两台厂用主变压器，互为备用的方式相接，保证供电的可靠性。绘制系统主接线图，优选厂区电气设备，根据发热和稳定性要求进行校验，最后确定防雷保护和接地措施，保证提高用电可靠性和经济运行。关键词：供电系统，负荷计算，短路计算，变压器，防雷设计IIAbstractWithconstantdevelopmentofscienceandtechnologyandtheprogressinginanall-roundwayofthesociety,thelivingstandardsofthepeopleareimprovingconstantly,theelectricenergyhasalreadygotdeeplytoourdailylifeandwork,thestudyonextremelyrelevantproblemsofdevelopmentofpowerindustryemergesinanendlessstream.Itisonthebasisofthecurrentsituationthatthepowerindustryofourcountrydevelopsatfullspeedatpresenttooriginallydesign,combinetheactualdemandfordevelopmentofnew-typefactory,advocatethepolicyofsafe,high-efficient,energy-conservation,collecttheswitchyard,distribution,illumination,automaticallycontrolandregulate,thebuildingdefendthunder,protection,computerequipmentcontrolandofferthepowerconsumingsystemintheintegrativemodernchemicalplant.Originallydesignincaseoffullyinvestigatingthefactoryaccordswithequipment,itneedscoefficientlawtocalculatethewholefactorytoloadelectricallytoadopt,signtheagreementwithelectricityindustrydepartmentinviewoftheabove,confirmthegradeofsupplyingpower.Carryonhavingaccordingtoactualdemandoffactoryworkcompensate,confirmapparenttocalculateloadsystematic,electricloaddifferenttodividedifferentloadclassificationintoaccordingtojobrequirementstheirthewholefactory,developandisitrequireaccordingtofactory,choosetwoplatformfactoryusethemainvoltagetransformertoplan,bothasreservewayandmeet,thedependabilityofguaranteeingtosupplypower.Drawthemainwiringdiagramofsystem,thefactoryelectricequipmentofoptimumseeking,andthestabilitydemandcarryoncheck-upaccordingtogeneratingheat,confirmfinallythatdefendsthunderprotectionandearthmeasure,guaranteetoimprovethedependabilityandeconomicaloperationofpowerconsuming.Keywords:Electricpowersystem,loadiscalculated,shortoutandcalculate,voltagetransformer,defendthethundertodesignIII目录摘要..........................................................IAbstract......................................................II1绪言......................................................11.1我国电力工业的发展的过程、现状和未来.......................11.2工厂供电系统设计的意义.....................................22负荷计算......................................................32.1该工厂负荷情况统计.........................................32.2本系统设计框图.............................................32.3计算方法...................................................42.4绘制最大负荷计算图.........................................42.5负荷计算...................................................52.5.1负荷计算.............................................52.5.2全厂电力负荷的分类..................................62.5.3绘制负荷等级指示图..................................62.6确定工厂供电电压等级.......................................62.7无功补偿...................................................62.7.1无功补偿的方式......................................62.7.2无功补偿容量的计算...................................73电线、电缆的选择...............................................93.1按载流量选择...............................................93.2按电压损失选择.............................................93.3与线路保护设备相配合选择...................................93.4热稳定校验.................................................94变压器选择..................................................114.1变压器类型的确定..........................................114.2变压器的过负荷能力.......................................114.2.1正常过负荷能力.......................................114.3变压器数量的确定.......................................124.3.1按负荷等级大小需选择变压器.........................124.3.2变压器容量的确定.....................................125电气主接线..................................................155.1电气主接线的要求及设计依据................................155.2常用的工厂电气接线图的比较................................156短路计算...................................................186.1短路的原因................................................186.2短路对设备及系统的危害....................................186.3短路电流计算的目的........................................186.4短路的类型................................................186.5本系统设计的一般规定和假设................................18IV6.6本系统的短路计算.........................................196.6.1短路计算用图.........................................196.6.2三相短路计算.........................................196.6.3单相短路电流计算....................................206.6.4短路电流的电动力效应.................................206.6.5短路电流的热效应.....................................207电气设备的选择...............................................227.1正常的工作条件选择........................................227.1.1按使用环境温度选型...................................227.1.2按额定电压选择.......................................227.1.3按额定电流选择、.....................................227.2低压电气设备选择.........................................227.2.1低压熔断器的选择计算.................................237.2.2自动空气断路器的选择.............................