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成人高等教育毕业设计题目：35kV箱式变电站设计摘要I摘要箱式变电站又称户外成套变电站，即将高压受电、变压器降压、低压配电等功能有机地组合在一起，安装在一个防潮、防锈、防尘、防鼠、防火、防盗、隔热、全封闭、可移动的钢结构箱体内，机电一体化，全封闭运行，特别适用于矿山、住宅小区等城市公用设施，用户可根据不同的使用条件、负荷等级选择箱式变电站。箱式变电站发展于20世纪60年代至70年代欧美等西方发达国家推出的一种户外成套变电所的新型变电设备，进入20世纪90年代中期，国内开始出现简易箱式变电站，并得到了迅速发展。随着中国城市现代化建设的飞速发展，城市配电网的不断更新改造，必将得到广泛的应用。本课题的主要内容包括箱式变电站的发展应用，箱式变电站的结构分类，以及箱式变电站一次系统设计极其设备选型以及二次系统设计。35kV箱式变电站的设计高压侧额定电压为35kV，低压侧额定电压为10kV，主变压器容量为5000kVA。主接线采用单母线分段接线。关键词：箱式变电站；结构，一次系统，二次系统目录II目录摘要······································································································Ⅰ目录······································································································Ⅱ第一章引言···························································································1第二章箱式变电站的类型、结构与技术特点·················································22.1箱式变电站的类型··············································································22.2箱式变电站的技术特点········································································22.3箱式变电站的箱体要求······································································3第三章35kV箱式变电站的总体结构设计······················································43.1箱式变电站对主接线的基本要求····························································43.2主接线的选择····················································································43.3高压接线方式····················································································53.4箱式变电站箱体的确定········································································53.5变压器的散热处理··············································································53.6箱式变电站总体布置···········································································5第四章35KV箱式变电站一次系统设计与设备选型··········································64.1一次系统设计····················································································64.2箱式变电站设备选型应注意的方面·························································64.3设备选型的基本原理···········································································64.4高压一次设备的选型···········································································74.5低压一次设备选型··············································································74.6高压熔断器的选择··············································································74.7开关柜的选型····················································································7第五章35kV箱式变电站二次系统设计·························································85.1二次系统的定义及分类········································································85.2电气测量仪表及测量回路·····································································85.3二次系统设计····················································································85.4断路器控制与信号回路········································································95.5控制回路设计····················································································10结论········································································································11参考文献·································································································12致谢········································································································13第一章引言-1-第一章引言随着矿山机电的发展，要求高压直接进入负荷中心，形成高压受电---变压器降压---低压配电的供电格局，所以供配电要向节地、节电、紧凑型、小型化的方向发展，箱式变电站(简称箱变)正是具有这些特点的最佳产品，因而在矿山电网中得到广泛应用。箱式变电站外壳采用钢板或者合金板，配有双层顶盖，隔热性好。外壳及骨架全部经过防腐处理，具有长期户外使有的条件。外形及色彩可与环境相互协调一致。安装方便。箱变高压侧采用负荷开关加限流熔断器保护。发生一相熔断器熔断时，用熔断器的撞针使负荷开关三相同时分闸，避免缺相运行。低压侧采用负荷开关加限流熔断器保护，自动空气开关欠电压保护或过电流保护就会动作，低压运行不会发生。第二章箱式变电站的类型、结构与技术特点-2-第二章箱式变电站的类型、结构与技术特点2.1箱式变电站的类型箱式变电站有美式箱式变电站和欧式箱式变电站。美式预装式变电站在我国叫做“预装式变电站”或“美式箱变”，它将变压器器身、高压负荷开关、熔断器及高低连线置于一个共同的封闭油箱内，构成一体式布置。用变压器油作为带电部分相间及对地的绝缘介质。同时，安装有齐全的运行检视仪器仪表，如压力计，压力释放阀，油位计，油温表等。欧式预装式变电站以前在我国习惯称为“组合式变电站”，它是将高压开关设备、配电变压器和低压配电装置布置在三个不同的隔室内，通过电缆或母线来实现电气连接。2.2箱式变电站的技术特点箱式变电站的高压室一般是由高压负荷开关、高压熔断器和避雷器等组成的，可以进行停送电操作并且有过负荷和短路保护。低压室由低压空气开关、电流互感器、电流表、电压表等组成的。箱式变中的电器设备元件，均选用定型产品，元器件的技术性能均满足相应的标准要求。各电器元件之间采用了机械联锁，各电器元件都安装在有足够强度和刚度的结构上，以便于导线的连接。操作采用电动方式，不需另配电源，由TV引出即可。另外箱式变还都具有电能检测、显示、计量的功能，并能实现相应的保护功能，还设有专用的接地导件，并有明显的接地标志。此外为适应户外工作环境，箱式变电站的壳顶一般都采用隔层结构，内装有隔热材料，箱体底部和各室之间都有冷却进出风口，采用自然风冷和自动控制的强迫风冷等多种形式，以保证电气设备的正常散热，具有防雨、防尘、防止小动物进入等措施。目前，国内生产的箱式变的电压等级：高压侧为3～35kV、低压侧为0.4～10kV。箱式变电站有如下特点：(1)技术先进安全可靠箱体部分采用目前国内领先技术及工艺，外壳一般采用镀铝锌钢板，框架采用标准集装箱材料及制作工艺，有良好的防腐性能，保证20年不锈蚀，内封板采用铝合金扣板，夹层采用防火保温材料，箱体内安装空调及除湿装置，设备运行不受自然气候环境及外界污染影响，可保证在－40℃～＋40℃的恶劣环境下正常运行。箱体内一次设备采用单元真空开关柜、干式变压器、干式互感器、真空断路器(弹第二章箱式变电站的类型、结构与技术特点-3-簧操作机构)等国内技术领先设备，产品无裸露带电部分，为全绝缘结构，完全能达到零触电事故，全站可实现无油化运行，安全性高，二次采用微机综合自动化系统，可实现无人值守。(2)工厂预制化设计时，只要设计人员根据变电站的实际要求，作出一次主接线图和箱外设备的设计，就可以选择由厂家提供的箱变规格和型号，所有设备在工厂一次安装、调试合格，真正实现变电所建设工厂化，缩短了设计制造周期；现场安装仅需箱体定位、箱体间电缆联络、出线电缆连接、保护定值校验、传动试验及其它需调试的工作，整个变电站从安装到投运大约只需5～8天的时间，大大缩短了建设工期。。(3)组合方式灵活箱式变电站由于结构比较紧凑，每个箱体均构成一个独立系统，这就使得组合方式灵活多变。(4)占地面积小。(5)投资省、见效快箱式变电站较同规模综自变电站减少投资40％～50％。2.3箱式变电站的箱体要求(1)箱体内照明、通风、防沙、散热应满足正常运行、维护要求，并应加装温度、湿度测量表计、凝露器、烟雾报警装置，并将温度、湿度、凝露、烟雾报警探头信号接入综合自动化系统，要考虑安装通讯设备的位置。(2)箱顶应考虑自然排水功能。(3)要抗紫外线辐射，抗暴晒性能好，不易导热可避免因外部温度过高而引起箱体温度升高。(4)防潮性能好，不会因冷热突变而产生凝露。(