国运一次降压变电所电气部分初步设计
中文摘要
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结合，运用理论知识和专业技能进行工程设计和科学研究，提高分析问题和解决问题的能力。本毕业设计的题目是国运220KV一次降压变电所电气部分初步设计，为了保证供电的可靠性、安全性以及满足远期负荷需要的要求，按照远期负荷规划进行初步设计，达到能够保证变电所长期可靠供电的目的。
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，设计过程中完成了主变选择、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以及防雷保护的规划等主要工作。近年来，电力在世界各国能源和经济发展中的作用日益增长，它已成为现代社会实用最广、需要最快的能源。变电所的合理设计与建设是一个极其重要的组成部分。整个设计过程中，全面细致的考虑工程设计的可靠性、经济性、灵活性等诸多因素，最终完成本设计方案。通过完成此毕业设计论文，进一步领会我国电力工业建设的政策观念和经济观点，培养对工程技术、经济进行较全面的综合分析能力。
关键词 电力系统，变电所，短路电流，电气设备
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沈阳工程学院毕业设计
Abstract
In this paper The professional graduate in system in electric power design is once more synthesize of training, it is we will during the period of school a profession for learning knowledge proceed theories and practice very good combination, make use of the theories knowledge proceeds with a profession for learning technical ability engineering design with science study. This graduate design thesis is a 220/60 KVs a declining to press to change to give or get an electric shock an electricity parts of first steps design.For the sake of dependable that guarantee the power supply with a request that contented long-term burthen, carries according to the forward the programming proceeding design developments, from but guarantee to change to give or get an electric shock can long-term dependable power supply.
Design the request of the mission book according to the graduate, synthesize a programming for learning profession knowledge and changing giving or get an electric shock the designed waiting dog's- ear relevantly contents, designing in the process completing lord changing choice, electricity lord connecting linear draw- up, short circuit computing, electricity equipments choosing, going together with electricity equiping, after give or get an electric shock the protection with the programming of the automatic device with defend protective programming in thunder etc. For this year, electric power is in international community energy with economy develop of the function increases increasingly. Change the reasonable design that give or get an electric shock are a with developments very constituting the part importantly.
Key Word electric power system，substation，short computing，electricity equipment
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国运一次降压变电所电气部分初步设计
目录
中文摘要 .......................................................................................................................................... I Abstract .......................................................................................................................................... II 第一部分 说明书 ........................................................................................................................... 1 第1章 变压器的选择 ................................................................................................................... 1 1.1 主变容量选择的有关规定 .................................................................................................. 1 1.2 主变选择的原则 .................................................................................................................. 1 1.2.1 主变台数的确定 ........................................................................................................... 1 1.2.2 变压器形式的选择 ....................................................................................................... 1 1.2.3 主变容量的确定 ........................................................................................................... 2 第2章 电气主接线的选择 ........................................................................................................... 3 2.1 概述 ...................................................................................................................................... 3 2.2 主接线的设计原则 .............................................................................................................. 3 2.2.1 考虑变电所在电力系统中的地位和作用 ................................................................... 3 2.2.2考虑近期和远期的发展规模 ........................................................................................ 3 2.2.3考虑负荷的重要性分级和出线回路数多少对主接线的影响 .................................... 3 2.2.4考虑主变台数对主接线的影响 .................................................................................... 3 2.2.5考虑备用容量的有无和大小对主接线的影响 ............................................................ 3 2.3 主接线设计的基本要求 ...................................................................................................... 4 2.3.1 可靠性 ........................................................................................................................... 4 2.3.2 灵活性 ........................................................................................................................... 4 2.3.3 经济性 ........................................................................................................................... 4 2.4 主接线的确定 ...................................................................................................................... 5 2.4.1 对原始资料的分析 ....................................................................................................... 5 2.4.2 主接线方案的拟定 ....................................................................................................... 5 2.5电气主接线图 ....................................................................................................................... 6 第3章 短路计算 ........................................................................................................................... 7 3.1 概述 ...................................................................................................................................... 7 3.2短路电流计算的主要目的 ................................................................................................... 7 3.3短路计算中的一般规定 ....................................................................................................... 7 3.4电路元件参数的计算 ........................................................................................................... 8 3.4.1基准值 ............................................................................................................................ 8 3.4.2各元件参数标么值计算 ................................................................................................ 8 3.4.3标么值表示的等值网络 ................................................................................................ 8 3.5 三相短路电流周期分量计算 .............................................................................................. 8 3.5.1影响短路电流变化规律的主要因素 ............................................................................ 9 3.5.2应用计算曲线的具体步骤如下： ................................................................................ 9 3.6 短路点选取 .......................................................................................................................... 9 第4章 电气设备的选择 ............................................................................................................. 10 4.1 概述 .................................................................................................................................... 10 4.1.1 一般原则 ..................................................................................................................... 10
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沈阳工程学院毕业设计
4.1.3 选择项目的说明 ......................................................................................................... 10 4.2 高压断路器的选择 ............................................................................................................ 11 4.3 高压隔离开关的选择 ........................................................................................................ 11 4.4 母线选择 ............................................................................................................................ 12 4.4.1软导线介绍 .................................................................................................................. 12 4.4.2一般要求 ...................................................................................................................... 13 4.5 电流互感器 ........................................................................................................................ 13 4.5.1参数选择 ...................................................................................................................... 13 4.5.2一次额定电流选择 ...................................................................................................... 13 4.5.3电流互感器准确级 ...................................................................................................... 13 4.5.4热稳定和动稳定校验 .................................................................................................. 13 4.6 电压互感器 ........................................................................................................................ 14 4.6.1 电压选择 ..................................................................................................................... 14 4.6.2 准确度选择 ................................................................................................................. 15 4.7 避雷器 ................................................................................................................................ 15 4.7.1 避雷器的参数 ............................................................................................................. 15 4.7.2 避雷器的配置 ............................................................................................................. 16 第5章 配电装置 ......................................................................................................................... 18 5.1 屋内外配电装置的安全净距 ............................................................................................ 18 5.1.1 概述 ............................................................................................................................. 18 5.1.2 分类及特点 ................................................................................................................. 18 5.1.3 屋内外配电装置的安全净距 ..................................................................................... 18 5.2 屋外配电装置 .................................................................................................................... 20 5.2.1 屋外高压配电装置的若干问题 ................................................................................. 20 5.3 设计原则 ............................................................................................................................ 21 5.4 设计要求 ............................................................................................................................ 22 5.4.1 满足安全净距的要求 ................................................................................................. 22 5.4.2 施工、运行和检修的要求 ......................................................................................... 22 第6章 继电保护及自动化装置规划设计 ................................................................................. 24 6.1 继电保护在电力系统中的作用 ........................................................................................ 24 6.2 继电保护的基本要求 ........................................................................................................ 24 6.3 选择保护配置及构成方案时的基本要求 ........................................................................ 24 6.4 主要设备继电保护配置 .................................................................................................... 25 6.4.1 变压器保护 ................................................................................................................. 25 6.4.2 母线保护 ..................................................................................................................... 26 6.4.3 线路保护 ..................................................................................................................... 27 6.5 自动化装置配置 ................................................................................................................ 27 6.5.1 自动重合闸 ................................................................................................................. 27 6.5.2 备用电源自动投入 ..................................................................................................... 28 第7章 过电压保护 ..................................................................................................................... 29 7.1 概述 .................................................................................................................................... 29 7.2 配电装置的防雷保护 ........................................................................................................ 29 7.3 防雷设计要求和所需资料 ................................................................................................ 29
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国运一次降压变电所电气部分初步设计
第二篇 计算书 ............................................................................................................................. 31 第8章 主变压器的选择 ........................................................................................................... 31 第9章 短路电流计算书 ............................................................................................................. 32 9.1 参数计算 ............................................................................................................................ 32 9.2 等值网络 ............................................................................................................................ 33 9.3 确定短路点 ........................................................................................................................ 34 9.4 网络化简 ............................................................................................................................ 34 9.5 短路计算 ............................................................................................................................ 35 9.5.1 D1点三相短路 ............................................................................................................ 35 9.5.2 D2点三相短路(两台变压器并列运行) ..................................................................... 37 第10章 电气设备选择计算 ....................................................................................................... 39 10.1 断路器选择 ...................................................................................................................... 39 10.1.1 220KV侧高压断路器的选择 ................................................................................... 39 10.1.2 60KV断路器选择 ..................................................................................................... 40 10.2 隔离开关的选择 ............................................................................................................ 41 10.2.1 220KV侧隔离开关的选择 .................................................................................... 41 10.2.2 60KV侧隔离开关的选择 ...................................................................................... 42 10．3母线的选择 .................................................................................................................... 42 10.3.1 220KV母线的选择 ................................................................................................... 43 10.3.2 60KV母线的选择 ..................................................................................................... 43 10.4 电流互感器的选择 .......................................................................................................... 44 10.4.1 220KV侧电流互感器的选择 ................................................................................... 44 10.4.2 60KV侧电流互感器的选择 .................................................................................. 45 10.5 电压互感器的选择 .......................................................................................................... 45 10.6 避雷器的选择 .................................................................................................................. 46 第11章 防雷保护计算 ............................................................................................................... 47 11.2 变电所避雷针布置图 ...................................................................................................... 47 11.3 保护范围计算 .................................................................................................................. 47 总结 ............................................................................................................................................... 49 致谢 ............................................................................................................................................... 50 参考文献 ....................................................................................................................................... 51 附录 ............................................................................................................................................... 53 A1.变电所电气主接线图 ............................................................................................................. 53 A2.变电所配电装置平面图 ......................................................................................................... 53 A3.变电所配电装置断面图 ......................................................................................................... 53 A4.全所防雷保护图 ..................................................................................................................... 53
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