火力发电厂毕业设计

新建300MW火力发电厂电气系统总体方案与布置设计

新建300MW火电厂电气系统总体方案与布置设计

摘要

目前，我国电力工业格局依旧是以火力发电为主。而300MW火力发电机组仍然是火力发电厂的主流发电机组。此次毕业课题设计的主题就是要针对新建300MW火力发电厂电气系统的方案与布置进行设计，主要是通过灵活运用所学的发电厂电气部分，电力系统暂态分析，电力系统稳态分析，电路原理，AutoCAD制图等专业知识结合工程实际来逐步有序的完成发电厂电气主接线的设计，厂用电接线，各种电气设备的选择及负荷分析计算等设计任务，并绘制各种电气接线图与配电装置图。在电气主接线的设计过程中严格遵守发电厂电气系统设计原则的同时灵活运用其它参考资料。针对提出的不同的设计方案进行深入的逐个对比分析和探讨，得出最佳设计方案。

关键词:火力发电厂，电气主接线，配电装置，电气系统

新建300MW火力发电厂电气系统总体方案与布置设计

NEW 300 MW COAL-FIRED POWER PLANT ELECTRICAL

SYSTEM OVERALL PLAN AND LAYOUT DESIGN

ABSTRACT

At present, our country electric power industry pattern is still predominantly coal-fired power.And 300MW thermal power unit is still the mainstream of the coal-fired power plant generating set.The graduation project design is according to the theme of the new 300MW coal-fired power plant electrical system of plan and layout design, mainly through the flexible use of knowledge of power plant electrical part, power system transient analysis of power system stability analysis, AutoCAD drawing and other professional knowledge combined with practical engineering to gradually and orderly complete power plant, the main electrical wiring design, auxiliary power wiring, selection of all sorts of electrical equipment and load analysis and calculation, etc. Design task, and map all kinds of electric wiring diagram and distribution equipment.In the process of the main electrical wiring design strictly abide by the principle of power plant electrical system design of flexible use of other resources at the same time. In view of the different design scheme is put forward by the in-depth comparative analysis and discussion, one by one the best design solution.

Key words: thermal power plant, the main electrical wiring, power distribution equipment,

electrical systems

新建300MW火力发电厂电气系统总体方案与布置设计

目录

第一篇 设计说明书 ................................................................................................................ 1 第一章 电气主接线设计 ........................................................................................................ 1

1.1 发电机电压级接线 ..................................................................................................... 1

1.1.1 发电机和变压器接线方式选择 ...................................................................... 1 1.2 220 kV电气主接线 ..................................................................................................... 2

1.2.1 220kV主接线方案的选取和比较 ................................................................... 3 1.3 6kV厂用电接线 .......................................................................................................... 5 1.4 500kV接线的选取和确定（二期扩建） .................................................................. 6 第二章 负荷计算及变压器选择 ............................................................................................ 9

2.1 厂用负荷计算 ............................................................................................................. 9

2.1.1 厂用电负荷的计算原则 .................................................................................. 9 2.1.2 厂用电负荷的计算方法 .................................................................................. 9 2.1.3 分段计算厂用负荷 ........................................................................................ 10 2.2 主变台数、容量和型式的确定 ............................................................................... 11

2.2.1 220kV侧主变压器容量、台数的确定 ......................................................... 11 2.2.2 主变压器型式、结构的确定 ........................................................................ 12 2.2.3 500kV侧主变压器的确定 ............................................................................. 12 2.2.4 联络变压器的确定 ........................................................................................ 12 2.3 厂用变台数、容量和型式的确定 ........................................................................... 13

2.3.1 厂用工作变压器台数、型式的确定 ............................................................ 13 2.3.2 厂用工作变压器容量的确定 ........................................................................ 13

第三章 最大持续工作电流及短路计算 .............................................................................. 17

3.1 各回路最大持续工作电流 ....................................................................................... 17

3.1.1 各个回路的最大持续电流的确定 ................................................................ 17 3.1.2 各个回路的最大持续电流 ............................................................................ 17 3.2 短路电流计算点的确定和短路电流计算 ............................................................... 18

新建300MW火力发电厂电气系统总体方案与布置设计 3.2.1 短路电流计算的目的和条件 ........................................................................ 18 3.2.2 计算短路点的确定方法 ................................................................................ 19

第四章 主要电气设备及各电压等级配电装置选择 .......................................................... 20

4.1 高压断路器的选择说明 ........................................................................................... 20

4.1.1 断路器选择的技术条件 ................................................................................ 21 4.2 隔离开关的选择说明 ............................................................................................... 21

4.2.2 隔离开关选择的技术条件 ............................................................................ 22 4.3 母线的选择说明 ....................................................................................................... 22

4.3.1 母线导体选择的技术条件 ............................................................................ 22 4.3.2 母线导体的热稳定校验 ................................................................................ 23 4.3.3、母线导体的动稳定校验 .............................................................................. 23 4.4 绝缘子、穿墙套管以及避雷器的选择说明 ........................................................... 24

4.4.1 型式、额定电压选择 .................................................................................... 24 4.4.2 动热稳定性校验 ............................................................................................ 24 4.5 电流互感器的配置和选择说明 ............................................................................... 25

4.5.1 电流互感器的配置 ........................................................................................ 25 4.5.2 电流互感器的技术条件 ................................................................................ 25 4.5.3、动稳定校验 .................................................................................................. 26 4.5.4、热稳定校验 .................................................................................................. 26 4.6 电压互感器的配置和选择说明 ............................................................................... 26

4.6.1 电压互感器的配置 ........................................................................................ 27 4.6.2 电压互感器的技术条件 ................................................................................ 27 4.7 各电压等级配电装置选择设计 ............................................................................... 27

4.7.1 配电装置的设计原则 .................................................................................... 28 4.7.2 配电装置设计要求 ........................................................................................ 28 4.7.3 配电装置设计的基本步骤 ............................................................................ 28 4.8 各主要电气设备选择结果一览表 ........................................................................... 29 第五章 继电保护系统总体配置方案 .................................................................................. 31

5.1 发电机变压器单元接线侧保护系统的配置 ........................................................... 31

5.1.1 短路保护 ........................................................................................................ 31