目 录
摘 要 ······································································································ Ⅰ 目 录 ······································································································ Ⅱ 第一章 前言 ·························································································· 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 电气主接线的确定 ·············································································· 4 3.2 主接线的基本形式 ·············································································· 4 3.3 箱式变电站对主接线的基本要求 ···························································· 5 3.4 主接线的比较与选择 ··········································································· 5 3.5 高压接线方式 ···················································································· 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 ······························································································
第一章 前言
箱式变电站是一种将中压开关设备、变压器、低压配电设备按照一定接线方案组合成一体的成
套配电设备。它与常规的土建变电站相比，具有占地面积小、现场安装工作量少、安装周期短、可以自由移动、减少线路损耗、投资少等优点。因此，在国外得到了广泛应用，而目前在国内，随着城乡电网改造，箱式变电站得到更多用户的认可
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
箱式变电站分为两大流派：欧式箱变和美式箱变。欧式箱变是将中压开关设备、变压器、低压配电设备各自分隔并排列成“目”字型或“品”字型，美式箱变则以变压器为主体，将负荷开关、后备保护熔断器、分接开关和变压器装在变压器油箱内，插入式熔断器、电缆和低压配电部分围绕变压器油箱排列，构成整体布置。欧式箱变的优点是结构灵活，适应性强；中压开关设备可以采用SF6环网柜、真空环网柜、压气式环网柜等。高压侧主接线方案灵活，变压器可以采用S9、S10等油浸变压器或SCB9等干式变压器；低压配电设备则完全可以根据用户要求量身定做，可以选用各种类型的低压配电设备如GGD、PGL，低压侧主接线可以包括进线柜、任意路数的出线柜以及无功补偿，缺点是体积偏大。而美式箱变的优点是体积小，由于变压器油箱即是美式箱变外壳的一部分，因此散热条件好，缺点是结构局限性太大，往往无法满足用户各种各样的需求，由于这两大流派各有优缺点，国内箱变制造厂家在市场竞争的
压力下，逐渐将这两大流派的技术特点加以融合，开发出一些派生类型。尽管类型有所不同，但基本原理大同小异，因此下面以欧式箱变为例进行探讨。
2.2 箱式变电站的技术要求
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，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。
(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。 (5)防腐、防裂、阻燃、防冻性能好。 (6)要机械强度高，耐压抗张，抗冲击。
(7)对环境有良好的协调性，能美化环境，可适应各种气候条件，外形美观，结构紧凑，箱体占地面积少，节约土地。
第三章 35kV箱式变电站的总体结构设计
3.1 电气主接线的确定 3.2 主接线的基本形式