变电所设计正文11

环北二次降压变电所电气部分初步设计

摘 要

电力系统专业的毕业设计是一次比较综合的训练，它是我们将在校期间所学的专业知识进行理论与实践的很好结合。

根据毕业设计任务书的要求，综合所学专业知识及《变电所设计》等书籍的有关内容，了主变选择、电气主接线的拟定、短路计算、电气设备选择、配电装置的规划、继电保护和自动装置的规划和防雷保护的规划等主要工作。在此期间，遇到的种种问题均通过反复比较、验算，并请教老师得以解决。毕业设计论文由设计说明书、设计计算书、一套图纸（电气主接线图、总平面布置图、配电装置断面图）组成。内容较为详细，对今后扩建有一定的参考价值。

关键词：电力系统 变电所 电气设备 配电装置

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沈阳工程学院毕业设计

ABSTRACT

The graduate professional power system design is a more integrated training, it is we will be in school during the school's expertise in theory and practice of good combination.

According to the design tasks of the graduation requirements, comprehensive study by the expertise and and other books relating to the contents of the design process to complete the main transformer choice, the main electrical wiring formulation, short-circuit, the choice of electrical equipment, power distribution Device planning, protection and automatic devices for planning and the protection of the mine planning, and other major work. In the meantime, the various problems were encountered by repeated comparison, checking and ask the teacher to solve. Design graduation thesis from design specification, design and calculation on a set of drawings (the main electrical wiring diagram, the general layout plans and distribution devices sections). Content in more detail in the future expansion of a certain value.

Key word: power system substation electricity equipment distribution device

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环北二次降压变电所电气部分初步设计

目 录

摘 要 ..................................................................................................................I ABSTRACT ........................................................................................................... II 设计引言 ................................................................................................................. 1 第1部分 说明书 .................................................................................................... 2 第1章 设计引论 ................................................................................................. 2 1.1 电力系统的一般概念 .................................................................................. 2 1.1.1 对电力系统运行的基本要求 .............................................................. 2 1.2 变电所的作用和工作原理及分类 .............................................................. 3 1.2.1 变电所的作用和工作原理 .................................................................. 3 1.2.2 变电所的分类 ...................................................................................... 3 第2章 设计任务 ................................................................................................. 4 2.1 设计的基本要求说明 .................................................................................. 4 2.1.1 设计地区环境 ...................................................................................... 4 2.1.2 系统网络图如下 .................................................................................. 4 2.1.4 10kV侧用户负荷表 .............................................................................. 5 2.1.5 其它条件 .............................................................................................. 5 2.2 设计主要内容 .............................................................................................. 5 2.3 设计范围及建设规模 .................................................................................. 5 第3章 主变压器及其无功补偿的选择 ............................................................. 6 3.1主变压器的选择 ........................................................................................... 6 3.1.1 主变压器台数的确定 .......................................................................... 6 3.1.2 主变压器容量的确定 .......................................................................... 6 3.2 功率因数的补偿及电容器的选择 .............................................................. 7 3.2.1 提高功率因数的意义 .......................................................................... 7 3.2.2 电容器组总容量确定的要求 .............................................................. 7 3.2.3 并联电容器组的基本接线类型 .......................................................... 8 3.2.4 并联电容器组每相内部的接线方式 .................................................. 8 3.2.5 并联电容器组的确定 .......................................................................... 8 第4章 电气主接线的选择 ................................................................................. 9 4.1 对电气主接线的说明 .................................................................................. 9 4.2 对电气主接线设计的基本要求 .................................................................. 9 4.2.1 可靠性 .................................................................................................. 9 4.2.2 灵活性 .................................................................................................. 9 4.2.3 经济性 .................................................................................................. 9 4.3 主接线的选择 ............................................................................................ 10 4.3.1 60kV侧主接线 .................................................................................... 10 4.3.2 10kV侧主接线 .................................................................................... 10 4.3.4 主接线方式的确定 ............................................................................ 11

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沈阳工程学院毕业设计

第5章 短路电流计算 ....................................................................................... 12 5.1 短路计算概述 ............................................................................................ 12 5.2 短路计算条件 ............................................................................................ 12 5.2.1 电气系统短路电流计算条件 ............................................................ 12 5.2.2 一般规定 ............................................................................................ 13 5.2.3 限制措施 ............................................................................................ 13 5.3 短路过程分析 ............................................................................................ 14 5.3.1 由“无限大容量系统”供电的三相短路电流 ................................ 14 5.3.2 由“有限容量系统”供电时的三相短路电流 ................................ 14 5.4 短路电流的计算方法 ................................................................................ 14 5.4.1 标幺值法的基本原理 ........................................................................ 15 5.5 短路电流的计算 ........................................................................................ 16 第6章 电气设备的选择 ................................................................................... 17 6.1 高压电器选择的一般要求 ........................................................................ 17 6.1.1 一般原则 ............................................................................................ 17 6.1.2 技术条件 ............................................................................................ 17 6.1.3 环境条件 ............................................................................................ 18 6.1.4 环境保护 ............................................................................................ 20 6.1.5 短路点选取 ........................................................................................ 20 6.2 高压断路器的选择 .................................................................................... 20 6.2.1 按额定电压选择 ................................................................................ 20 6.2.2 按额定电流选择 ................................................................................ 20 6.2.3 按开断电流选择 ................................................................................ 21 6.2.4 按额定关合电流选择 ........................................................................ 21 6.2.5 动稳定校验 ........................................................................................ 21 6.2.6 热稳定校验 ........................................................................................ 21 6.2.7 高压断路器的确定 ............................................................................ 21 6.3 高压隔离开关的选择 ................................................................................ 22 6.4 电流互感器的选择 .................................................................................... 22 6.4.1 设备种类的选择 ................................................................................ 22 6.4.2 按一次额定电压和额定电流选择 .................................................... 22 6.5 电压互感器的选择 .................................................................................... 23 6.5.1 装置种类和型式选择 ........................................................................ 23 6.5.2 按一次回路电压选择 ........................................................................ 23 6.5.3 按二次回路电压选择 ........................................................................ 24 6.5.4 按准确级和容量选择 ........................................................................ 24 6.6 高压开关柜的选择 .................................................................................... 24 6.6.1 高压开关柜的介绍 ............................................................................ 24 6.6.2 高压开关柜结构特点 ........................................................................ 25 6.6.3 高压开关柜选用指导意见 ................................................................ 25 6.6.4 高压开关柜的确定 ............................................................................ 25

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环北二次降压变电所电气部分初步设计

6.7 母线的选择 ................................................................................................ 25 6.7.1 选择条件 ............................................................................................ 25 6.7.2 导体截面选择和校验 ........................................................................ 26 6.7.3 母线的确定 ........................................................................................ 26 第7章 配电装置的规划 ................................................................................... 27 7.1 电工建筑物总平面布置的基本原则 ........................................................ 27 7.2 本所电气布置规划方案 ............................................................................ 27 7.2.1 60kV侧室外部分 ................................................................................ 27 7.2.2 10kV侧室外部分 ................................................................................ 27 7.2.3 10kV侧室内部分 ................................................................................ 27 第8章 继电保护及自动装置规划设计 ........................................................... 29 8.1 继电保护的配置 ........................................................................................ 29 8.1.1 电力系统继电保护的作用 ................................................................ 29 8.1.2 继电保护的要求 ................................................................................ 29 8.1.3 变压器保护的配置 ............................................................................ 29 8.1.4 10kV侧母线保护 ................................................................................ 30 8.1.5 10kV侧线路保护 ................................................................................ 31 8.2 自动装置的配置 ........................................................................................ 31 8.2.1 配置原则 ............................................................................................ 31 8.2.2 自动重合闸的作用 ............................................................................ 31 8.2.3 自动重合闸装置应符合的基本要求 ................................................ 31 8.2.4 待设变电所自动装置配置 ................................................................ 32 8.2.5 备用电源和备用设备自动投入 ........................................................ 32 8.3 继电保护与自动装置的确定 .................................................................... 32 第9章 过电压防雷保护的规划设计 ............................................................... 33 9.1 避雷器的选择 ............................................................................................ 33 9.1.1 避雷器的选择要求 ............................................................................ 33 9.1.2 避雷器的确定 .................................................................................... 33 9.2 雷击过电压保护 ........................................................................................ 34 9.2.1 直击雷的保护范围 ............................................................................ 34 9.2.2 避雷针的装设原则及接地装置的要求 ............................................ 34 9.2.3 避雷针保护范围计算 ........................................................................ 34 第2部分 计算书 .................................................................................................. 35 第10章 主变压器及功率补偿电容器组的选择 ............................................. 35 10.1 主变压器的选择 ...................................................................................... 35 10.1.1 变电所所有负荷的总功率 .............................................................. 35 10.1.2 变电所所有负荷的总容量 .............................................................. 35 10.1.3 主变压器容量的确定 ...................................................................... 35 10.2 功率因数的补偿及电容器组的选择 ...................................................... 36 10.2.1 功率因数的补偿 .............................................................................. 36 10.2.2 补偿容量的确定 .............................................................................. 36 10.2.3 补偿容量的校验 .............................................................................. 36

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