成人高等教育毕业设计
题 目：
35kV箱式变电站设计
35kV箱式变电站设计
东北林业大学 电器工程及其自动化 2012级
史 宇
内容摘要：在我国目前箱式变电站使用的广泛、各行各业都在使用，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，特别适用于负荷集中的经济开发区、工厂、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。
关键词：箱式变电站 一次系统 二次系统 设计 选型。
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目 录
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 ················································· 1 2.1 箱式变电站的类型 ·············································································· 2 2.2 箱式变电站的技术 ·············································································· 2 2.3 箱式变电站的箱体要求 ······································································ 4 第三章 35kV箱式变电站的总体结构设计 ······················································ 5 3.1 箱式变电站对主接线的基本要求 ···························································· 5 3.2 主接线的选择 ···················································································· 5 3.3 高压接线方式 ···················································································· 5 3.4 箱式变电站箱体的确定 ········································································ 6 3.5 变压器的散热处理 ·············································································· 6 3.6 箱式变电站总体布置 ··········································································· 6 第四章 35KV箱式变电站一次系统设计与设备选型 ·········································· 6 4.1 一次系统设计 ···················································································· 6 4.2 箱式变电站设备选型应注意的方面 ························································· 7 4.3 设备选型的基本原理 ··········································································· 7 4.4 高压一次设备的选型 ··········································································· 7 4.5 低压一次设备选型 ·············································································· 7 4.6 高压熔断器的选择 ·············································································· 8 4.7 开关柜的选型 ···················································································· 8 第五章 35kV箱式变电站二次系统设计 ························································· 8 5.1 二次系统的定义及分类 ········································································ 8 5.2 电气测量仪表及测量回路 ····································································· 8 5.3 二次系统设计 ···················································································· 9 5.4 断路器控制与信号回路 ········································································ 9 5.5 控制回路设计 ···················································································· 10 结论 ········································································································ 11 参考文献 ······························································································ 12
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结 论
第一章 引 言
随着我国经济的发展、工业经济集中开发区、工厂、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
2.1 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、
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结 论
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，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(弹簧操作机构)等技术领先设备，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。
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电气工程及其自动化毕业论文（已通过审核）
