毕业论文 基于PSCAD超高压系统输电线路故障分析

内蒙古科技大学毕业设计说明书（毕业论文）

基于PSCAD超高压系统输电线路故障分析

摘 要

故障计算和分析是电力系统规划、设计和运行中的一项重要工作， 随着我国电网的快速发展， 传统方法已经不能满足需要， 运用计算机进行仿真和计算是大势所趋。文章以PSCAD为工具， 对电力系统进行故障模拟， 并以国家电网公司750kV输变电示范工程为基本模型，人为地设置系统部分参数和故障类型， 求其故障电流和故障电压以及相关数据， 避免了采用一般程序设计语言建立电力系统模型的繁琐步骤， 快速而准确地实现了电力系统故障的仿真实验和数据分析。

关键词: 超高压系统; PSCAD软件; 仿真分析

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内蒙古科技大学毕业设计说明书（毕业论文）

System based on PSCAD EHV transmission line fault analysis

Abstract

The analysis and calculation of fault is an important task for the programming， designing and running of power system. With the rap id growth of power system， the traditional ways and means can’t satisfy needs， it is necessary to use computer to simulate and calculate. This paper simulates the faults， sets the system parameters and fault types， And to the State Grid Corporation of 750kV transmission pilot project for the basic model， calculates the fault current and voltage by PSCAD. It avoids the cockamamie app roaches of commonly programming language， it realizes the fault simulation experiment and analyzes fast and exactly.

Key words: EHV system; PSCAD; Simulation

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内蒙古科技大学毕业设计说明书（毕业论文）

目录

摘 要 ...........................................................................................................................................I Abstract ...................................................................................................................................... II 第一章

引 言 ......................................................................................................................... 1

1.1 750kV输变电示范工程简介 ...................................................................................... 1 1.2超高压系统输电线路故障基本知识 .......................................................................... 1

1.2.1超高压系统输电线路故障分类 ......................................................................... 1 1.2.2短路的故障的危害 ............................................................................................. 2 1.2.3非全相运行的特点 ............................................................................................. 3 1.3本文的章节安排 .......................................................................................................... 3 第二章

输电线路故障的分析计算 ....................................................................................... 5

2.1三相短路电流的实用计算 .......................................................................................... 5 2.2不对称故障的分析计算 ............................................................................................ 10

2.2.1对称分量法的基本原理 ................................................................................... 11 2.2.2单相接地短路故障的分析计算 ....................................................................... 12 2.2.3两相短路故障的分析计算 ............................................................................... 14 2.2.4两相短路接地故障的分析计算 ....................................................................... 17 2.2.5一相断线故障的分析计算 ............................................................................... 20 2.2.6两相断线故障的分析计算 ............................................................................... 21 2.3 750kV输变电示范工程未知量计算 ........................................................................ 23 第三章

超高压输电系统故障的仿真研究 ......................................................................... 25

3.1仿真软件的简介 ........................................................................................................ 25 3.2短路故障的仿真分析 ................................................................................................ 28

3.2.1正常情况的仿真分析 ....................................................................................... 28 3.2.2单相接地短路的仿真分析 ............................................................................... 31 3.2.3两相短路接地的仿真分析 ............................................................................... 35 3.2.4两相短路的仿真分析 ....................................................................................... 39 3.2.5三相短路的仿真分析 ....................................................................................... 43 3.3断线故障的仿真分析 ................................................................................................ 47

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内蒙古科技大学毕业设计说明书（毕业论文）

3.3.1正常情况的仿真分析 ....................................................................................... 47 3.3.2.一相断线故障的仿真分析 ............................................................................... 49 3.3.3两相断线故障的仿真分析 ............................................................................... 51

3.4本章小结 ............................................................................................................................ 54 第四章

电力线路相关继电保护的介绍 ............................................................................. 55

4.1继电保护的基本原理 ................................................................................................ 55 4.2电网的电流保护 ........................................................................................................ 56

4.2.1单侧电源网络相间短路的电流保护 ............................................................... 56 4.2.2方向性电流保护的工作原理 ........................................................................... 59 4.2.3大电流接地系统的零序电流保护 ................................................................... 60 4.3电网的距离保护 ........................................................................................................ 61 4.4 750kV及以上特高压输电线上重合闸的应用 ........................................................ 62

4.4.1三相重合闸在特高压输电线上的应用问题 ................................................... 62 4.4.2单相重合闸在特高压输电线上的应用问题 ................................................... 63 4.5继电保护的发展简史 ................................................................................................ 64 第五章

结 论 ....................................................................................................................... 66

参考文献 .................................................................................................................................. 68 致 谢 ........................................................................................................................................ 69

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