电气工程自动化毕业论文

电气工程自动化毕业设计

题 目：

35kV箱式变电站设计

摘 要

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 ················································· 2 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 ······································································ 3 第三章 35kV箱式变电站的总体结构设计 ······················································ 4 3.1 箱式变电站对主接线的基本要求 ···························································· 4 3.2 主接线的选择 ···················································································· 4 3.3 高压接线方式 ···················································································· 5 3.4 箱式变电站箱体的确定 ········································································ 5 3.5 变压器的散热处理 ·············································································· 5 3.6 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 ·········································· 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 ························································· 6 4.3 设备选型的基本原理 ··········································································· 6 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 ·············································································· 7 4.7 开关柜的选型 ···················································································· 7 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 ···················································································· 8 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 ······························································································

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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

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