基于MATLAB仿真的电力系统故障分析

毕业设计（论文）

基于MATLAB仿真的电力系统故障分析

学专学学指

院业生生导

名名学姓教

称 称 号 名 师

学院名称 专业名称 学生学号 学生姓名 教授姓名 老师姓名

助理指导老师

202 年 月

目 录

摘要 ........................................................................ I Abstract .................................................................... II 1 绪论 ...................................................................... 1 1.1 电力系统短路故障的危害 ................................................ 1 1.2 基于Matlab仿真系统故障的前景 ......................................... 1 2 无穷大功率电源供电系统三相短路仿真 ........................................ 1 2.1无穷大功率电源供电系统三相短路的暂态过程 .............................. 2 2.2无穷大功率电源供电系统仿真模型构建 .................................... 3 2.3 Matlab仿真模型及结果分析 .............................................. 9 3 基于Matlab仿真的同步发电机突然短路的暂态过程分析 ........................ 11 3.1同步发电机突然三相短路暂态过程分析 ................................... 12 3.2 同步发电机突然三相短路暂态过程的数值计算与Matlab仿真 ................ 13 3.2.1同步发电机突然三相短路暂态过程的数值计算 ......................... 13 3.2.2同步发电机突然三相短路暂态过程的Matlab仿真 ...................... 15 4 基于Matlab仿真的小电流接地系统单相故障分析 .............................. 19 4.1 小电流接地系统单相故障特点简介 ....................................... 19 4.2 小电流接地系统仿真模型构建 ........................................... 21 4.2.1中性点不接地系统的仿真模型及计算 ................................. 21 4.2.2中性点经消弧线圈接地系统的仿真模型及计算 ......................... 24 4.3小电流接地系统单相故障仿真结果及分析 ................................. 25 4.3.1中性点不接地系统的仿真结果及分析 ................................. 26 4.3.2中性点经消弧线圈接地系统的仿真结果及分析 ......................... 28 5 结论与展望 ............................................................... 29 参考文献 ................................................................... 31 致谢 ....................................................................... 32

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Contents

Abstract ......................................................................................................................... II 1 Introduction ................................................................................................................. 1 1.1 The harm of electric power system short circuit fault ........................................... 1 1.2 The prospect of the fault simulation system based on Matlab ............................... 1 2 The infinite power three-phase power system short circuit simulation ...................... 1 2.1 Transient process of three-phase short circuit in infinite power supply system .. 2 2.2 Simulation mode construction of power supply system for infinite power supply3 2.3 The result and analysis of simulation................................................................... 9 3 Transient simulation of sudden short circuit for synchronous generator .................. 11 3.1 the introduction of the process of the sudden three-phase short circuit transient of synchronous generator ............................................................................................. 12 3.2 Numerical calculation and simulation of the sudden three-phase short circuit transient of synchronous generator .............................................................................. 13 3.2.1 Numerical calculationof the sudden three-phase short circuit transient of synchronous generator ................................................................................................. 13 3.2.2 Simulation method for the sudden three-phase short circuit transient of synchronous generator ................................................................................................. 15 4 Single phase fault of small current grounding system .............................................. 19 4.1 Brief introduction to the characteristics of single phase fault in small current grounding system ......................................................................................................... 19 4.2 Simulation model construction of small current grounding system .................... 21 4.2.1The simulation model and the calculation of neutral point grounding system21 4.2.2The simulation model and calculation of the grounding system of the neutral point via the arc suppression coil ................................................................................. 24 4.3 Simulation results and analysis ...............................................错误!未定义书签。 3.3.1The results of simulation and analysis of neutral point grounding system .... 26 3.3.2The simulation results and analysis of the grounding system of the neutral point via the arc suppression coil ................................................................................. 28 5 Conclusion and prospect ........................................................................................... 29 Reference ..................................................................................................................... 31 Thanks .......................................................................................................................... 32

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基于MATLAB仿真的电力系统故障分析

摘要:电力系统故障分析主要是研究电力系统中由于故障所引起的电磁暂态过程，搞清楚暂态发生的原因、发展过程及后果，从而为防止电力系统故障、减少故障损失提供必要的理论知识。简单故障和复合故障是电力系统可能发生的故障类别。简单故障指的是电力系统正常运行时某一处发生短路或断相故障，而复合故障则是指两个或两个以上简单故障的组合。所谓短路，是指电力系统正常运行情况以外的相与相之间或相与地之间的连接。在正常运行时，除中性点外，相与相或相与地之间是绝缘的。单相短路故障在电力系统的运行中占绝大多数。三相短路时三相回路依旧是对称的，故称为对称短路；其他几种回路均使三相回路不对称，故称为不对称短路。产生短路的主要原因是电气设备载流部分的相间绝缘或相对地绝缘被破坏。短路对电力系统的正常运行和电气设备有很大的危害。短路引起电网中电压降低；系统发生短路相当于改变了电网的结构，必然引起系统中功率分布的变化；不对称接地短路所引起的不平衡电流产生的不平衡磁通，会在邻近的平行的通信线路内感应出相当大的感应电动势，造成对通信系统的干扰，甚至危及设备和人身的安全。 关键词：电力系统故障、电磁暂态过程、功率分布、感应电动势

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