湖 南 科 技 大 学
毕 业 设 计（ 论 文 ）
题作学专学
目 者 院 业 号
某小区供配电设计
王一旭
信息与电气工程学院 电气工程及其自动化
0754010426 王志英
二〇〇一二 年 六 月 五 日
指导教师
湖南科技大学（毕业论文）
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摘 要
要提高小区配电系统的可靠性，要正确选择各类配电设备的容量，就必须科学，合理的进行负荷计算。
本文对负荷计算中的相关问题进行了分析和探讨，就重要设备的容量选择做了详细的的论述，提出了一些进一步提高配电系统可靠性的措施，并结合工程实例进行负荷计算，计算结果证明本文所述方法是正确合理，可以在实际中应用。
另外，本文还利用MTALAB仿真软件对供电系统短路故障进行了仿真，并制作了相应的电路图以及对防雷措施进行了仔细的分析。
关键词：变压器,高压断路器,箱式变电站
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湖南科技大学（毕业论文）
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ABSTRACT
To improve the distribution system reliability, and correctly choose the capacity of power distribution device, it must be scientific, reasonable carries on the load computation.
In this paper, the load calculation and the related problems are analyzed and discussed, the important equipment capacity choice has made the detailed elaboration. It puts forward some suggestions to improve the distribution system reliability measures, combined with engineering example, load calculation.The calculation results prove that the method is correct and reasonable, and it can be applied in practice.
In addition, this paper also makes use of MTALAB simulation software for power system fault simulation, and made the corresponding circuit diagram and the lightning protection measures are analyzed in detail.
Keywords: Transformer, High voltage circuit breaker, Box-type transformer substation
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湖南科技大学（毕业论文）
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目 录
摘 要 ....................................................................................................................... 2 ABSTRACT ................................................................................................................... 3 第一章 概述 ................................................................................................................. 7
1.1工程概述.......................................................................................................... 7 1.2供配电设计一般原则...................................................................................... 7 1.3供配电系统设计要则...................................................................................... 8 1.4本设计设计内容.............................................................................................. 9 第二章 负荷统计 ....................................................................................................... 10
2.1负荷分级及供电要求.................................................................................... 10
2.1.1电力负荷的分级................................................................................. 10 2.1.2各级电力负荷对电源的要求............................................................. 10 2.1.2本设计负荷分级................................................................................. 11 2.2负荷统计........................................................................................................ 11 第三章 无功补偿及变压器的选择 ........................................................................... 14
3.1无功补偿的目的............................................................................................ 14
3.1.1无功功率............................................................................................. 14 3.1.2影响功率因数的主要因素................................................................. 14 3.1.3供电部门对平均功率因数的要求..................................................... 14 3.1.4提高自然功率因数的方法................................................................. 15 3.2无功补偿方法................................................................................................ 15
3.2.1无功补偿装置的选择......................................................................... 15 3.2.2无功补偿装置的安装方法................................................................. 16 3.3无功补偿初步计算........................................................................................ 17 3.4变压器的选择................................................................................................ 18
3.4.1电力变压器的类型选择....................................................................... 18 3.4.2电力变压器的台数和容量选择........................................................... 18 3.4.3电力变压器的过负荷能力................................................................. 19 3.5本设计变压器的选择.................................................................................... 20
3.5.1配电房方案选择................................................................................... 20 3.5.2箱式变电站........................................................................................... 20 3.5.3变压器的选择....................................................................................... 21 3.6无功补偿及变压器方案的确定.................................................................... 22
3.6.1无功补偿及变压器方案选定过程....................................................... 22 3.6.2本设计无功补偿及变压器方案总结................................................... 25
第四章 供配电系统接线方案 ................................................................................... 27
4.1电力配电系统基本原则................................................................................ 27 4.2常用高压电力配电方式................................................................................ 28 4.3变配电所主接线............................................................................................ 29
4.3.1变配电所主接线的基本形式............................................................... 29 4.3.2变配电所主接线的一般要求............................................................... 30 4.4常用低压电力配电方式................................................................................ 31 4.5本设计中所采用的供配电系统方案............................................................ 32
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湖南科技大学（毕业论文）
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4.6电能计量方式................................................................................................ 32 第五章 主线路线型及主要柜体的选择 ................................................................... 33
5.1主线路线型选择............................................................................................ 33
5.1.1导体材料的选择................................................................................... 33 5.1.2普通电缆绝缘材料及护套选择........................................................... 33 5.1.3各主线路的计算电流........................................................................... 35 5.1.4个主线路线型选择............................................................................... 36 5.2主要高压开关柜的选择................................................................................ 38
5.2.1高压成套装置....................................................................................... 38 5.2.2预装式变电站高压单元常用成套装置............................................... 38 5.2.3交流高压负荷开关............................................................................... 38 5.2.4高压断路器........................................................................................... 39 5.2.5本设计负荷开关柜的选择................................................................... 39 5.3主要低压成套开关设备和控制设备柜体选择............................................ 39
5.3.1低压成套开关设备和控制设备........................................................... 39 5.3.2低压成套开关设备和控制设备的分类.................................................... 40
5.3.3低压断路器........................................................................................... 41 5.3.4开关、隔离开关及熔断器组合电器................................................... 41
第六章 短路电流及保护电器的选择 ....................................................................... 43
6.1短路电流计算概述........................................................................................ 43
6.1.1短路的类型........................................................................................... 43 6.1.2短路计算的目的................................................................................... 43 6.1.3短路计算的假定条件........................................................................... 43 6.1.4典型的短路电流波形曲线................................................................... 44 6.2主电路短路电流的计算................................................................................ 44 第七章Matlab仿真 ................................................................................................... 45
7.1 Matlab简介.................................................................................................. 45 7.2仿真对象介绍................................................................................................ 45 7.3仿真电路与结果............................................................................................ 46 第八章 防雷接地系统设计 ....................................................................................... 47
8.1接地系统选择................................................................................................ 47
8.1.1接地的基本概念................................................................................. 47 8.1.2接地的分类........................................................................................... 47 8.1.3低压系统接地种类............................................................................... 48 8.1.4本设计接地系统选择........................................................................... 49 8.2等电位联结.................................................................................................... 49
8.2.1等电位联结的作用............................................................................... 49 8.2.2等电位联结的分类............................................................................... 49 8.2.3等电位联结的安装与设计方案........................................................... 50 8.3建筑物的防雷分类........................................................................................ 51 8.4建筑物的防雷措施........................................................................................ 52 第九章 继电保护 ....................................................................................................... 55
9.1继电保护和自动装置一般要求.................................................................... 55 致 谢 ........................................................................................................................... 57
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