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摘要I摘要本设计初步设计了煤矿地面35kV变电站的设计。其设计过程主要包括负荷计算、主接线设计、短路计算、电气设备选择、继电保护方案、变电所的防雷保护与接地等。通过对煤矿35KV变电站做负荷统计，用需用系数法进行负荷计算，根据负荷计算的结果确定出该站主变压器的台数、容量及型号。用标幺值法对供电系统进行了短路电流计算，为电气设备的选择及校验提供了数据。根据煤矿供电系统的特点，制定了矿井变电所的主结线方式、运行方式、继电保护方案。其中35KV侧为全桥接线，6KV主接线为单母分段。两台主变压器采用分列运行方式。并根据电流整定值以及相关数据的校验，选择了断路器、隔离开关、继电器、变压器等电气设备。关键字：负荷计算;变电站;继电保护;运行方式AbstractIIAbstractThedesignofthepreliminarydesignofminesurfacesubstationdesign35kV.Thedesignprocessmainlyincludestheloadcalculation,themainwiringdesign,short-circuitcalculation,equipmentselection,theschemesofrelayprotection,substationlightningprotectionandgrounding.Theminethrough35KVsubstationloadstatistics,withtherequiredcoefficientofloadcalculation,accordingtotheloadcalculationresultsidentifythestation,thenumberofmaintransformercapacityandmodels.Useofper-unitvaluemethodofpowersupplysystemforshort-circuitcurrentcalculation,forelectricalequipmentselectionandvalidationprovidesdata.Accordingtothecharacteristicsofcoalminepowersupplysystem,developedminesubstationmainwiringmode,operationmode,relayprotectionscheme.The35KVsideforthewholebridgeconnection,6KVmainconnectiontosingleparentsegment.Twomaintransformerinoperation.Accordingtothecurrentsettingvalueandassociateddatacheck,choiceofcircuitbreaker,isolatingswitch,relays,transformersandotherelectricalequipment.Keywords:Loadcalculation;Transformersubstation;Relayprotection;Operationmode目录目录摘要..............................................................IABSTRACT.........................................................II1绪论..............................................................11.1某煤矿采区原始资料：..........................................11.2采区机电负荷一览表：..........................................21.3采区巷道长度：................................................31.4采区供电系统示意图............................................32.矿用电气设备的选择策略............................................42.1煤矿电气设备防爆类型..........................................42.1.1对矿用电气设备的结构要求..................................42.2井下电气设备防爆原理..........................................52.2.1隔爆外壳..................................................52.2.2本质安全型电路............................................52.2.3超前切断电源和采用快速断电系统............................52.3矿用电气设备的类型............................................62.3.1矿用一般型................................................62.3.2矿用防爆型.................................................62.4各种电压不合格情况............................................62.4.1外接电源电压过高或过低.....................................62.4.2三相电压不平衡.............................................62.4.3电动机负载太大.............................................62.4.4运行环境不良...............................................72.5其他注意事项..................................................72.6各种电器设备..................................................72.7矿用电气设备的选用............................................73采区低压供电网络的计算............................................83.1供电系统的确定：..............................................83.2本系统用电设备负荷例表计算：..................................93.3供电设备的选择及校验..........................................93.3.1变压器容量计算.............................................9目录3.3.2变压器的选择...............................................93.3.3变压器的主要技术参数：.....................................93.4低压电缆的选择................................................93.4.1选择原则：................................................103.4.2电缆型号的确定：..........................................103.4.3电缆长度的确定：..........................................103.4.4电缆截面的确定............................................103.4.5电缆芯线数的确定..........................................103.4.6电缆截面选择计算..........................................103.5低压开关的选择...............................................123.5.1选择原则：................................................123.5.2低压开关型号的确定：......................................133.6低压电缆及低压开关的校验：...................................143.6.1低压电缆短路电流的计算：.................................143.6.2低压开关继电器保护装置的整定校验：.......................154采区电气设备的选择...............................................164.1采区高压开关柜的选择.........................................164.1.1采区高压开关柜的选择的原则................................164.2矿用低压隔爆开关选择.........................................174.2.1选择原则..................................................174.2.2选择计算公式及选择条件....................................175短路电流的计算...................................................185.1系统电抗.....................................................185.2变压器的阻抗.................................................185.3短路电流计算表...............................................195.3.1动作电流..................................................205.3.2灵敏度检验................................................205.4反时限过流保护...............................................205.4.1动作电流..................................................205.4.2动作时限..................................................206采区漏电保护措施.................................................21目录6.1变压器中性点不直接接地供电系统的漏电保护措施.................216.2对低压电网漏电保护的要求.....................................217煤矿井下采区电气设