2011届毕业生毕业论文（设计）
题目：复杂电网不对称故障分析与计算及其
程序设计
院(系)别 信息工程系 专 业 电气工程及其自动化 届 别 2007级 学 号 070812211
二○一一年六月
山东交通学院毕业设计（论文）
摘 要
随着电力事业的快速发展，电力电子新技术得到了广泛应用；出于技术、经济等方面的考虑，500kV及以上的超高压输电线路普遍不换位，再加上大量非线性元件的应用，电力系统的不对称问题日益严重。因此电力系统不对称故障分析与计算显得尤为重要。
基于对称分量法的基本理论，对称分量法采取的具体方法之一是解析法，即把该网络分解为正，负，零序三个对称序网，这三组对称序分量可分别按对称的三相电路分解。计算机程序法。通过计算机形成三个序网的节点导纳矩阵，然后利用高斯消去法通过相应公式对他们进行数据运算，即可求得故障端点的等值阻抗。最后根据故障类型选取相关公式计算故障处各序电流，电压，进而合成三相电流电压。
基于此方法，运用VC6.0设计开发了一个电网故障计算分析的通用程序。此程序具有良好的人机界面，计算速度快，计算结果准确。文中最后以某电网为例进行了计算，其结果验证了程序的有效性。
关键词: 参数不对称，故障计算与分析，通用程序
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李磊：复杂电网的不对称故障分析与计算及其程序设计
Abstract
With the rapid development of power industry, power electronic technology has been widely used; For technical and economic considerations, 500kV and above transmission lines are generally not transposition, together with the application of a large number of nonlinear elements , the power system the growing problem of asymmetry. Therefore, asymmetric power system fault analysis and calculation is very important.
Based on the basic theory of symmetry, symmetry is one of the specific method to resolve the law, that to the network is decomposed into positive, negative and zero sequence network of the three symmetric sequence, these three groups of symmetry by symmetric sequence components, respectively Decomposition of three-phase circuits. Computer procedures. Sequence of three computer-based network node admittance matrix, and then use the appropriate formula by Gauss elimination method for data on their operations, one can fault endpoint equivalent impedance. Finally, select the associated fault type fault Department calculated the sequence current voltage, and then synthesis of three-phase voltage and current.
Baseg on the method and by using VC 6.0 a universal program for power grid fault calculation and analysis is designed.The program has a good man-machine interface and it is effective and precise .In the end a prow grid is analyzed as an example,the result shows the effective of the program.
Key Words: Parameters of asymmetry, Fault calculation and analysis, Universal program
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山东交通学院毕业设计（论文）
目 录
前 言 .................................................................... 1 1 绪论 .................................................................... 2
1.1 课题的背景 ........................................................ 2 1.2 电网故障计算方法现状研究 .......................................... 2 1.3 本文主要研究工作 .................................................. 3 2 电力系统故障分析的基本知识 .............................................. 4
2.1 短路故障的基本知识 ................................................ 4
2.1.1 短路的概念 .................................................. 4 2.1.2 短路的种类 .................................................. 4 2.1.3 短路的现象及后果 ............................................ 6 2.2断相故障及复杂故障 ................................................ 7 2.3故障计算的基本假设 ................................................ 7 3复杂电网的不对称故障分析方法介绍与比较 .................................. 9
3.1 基于潮流计算的不对称故障分析法 .................................... 9
3.1.1 故障分析时的数学模型 ........................................ 9 3.1.2 故障计算求解步骤 ........................................... 10 3.2基于相分量法的不对称故障分析法 ................................... 11
3.2.1 网络模型 ................................................... 11 3.2.2相分量法在简单电路中计算应用 ............................... 12 3.3 对称分量法 ....................................................... 14
3.3.1 对称分量法介绍 ............................................. 14 3.3.2对称分量法在简单不对称短路中的应用 ......................... 16 3.4 三种方法的比较与选择 ............................................. 17 4复杂电网的不对称故障分析与计算 ......................................... 19
4.1不对称故障类型解析 ............................................... 19
4.1.1单相（a相）接地短路 ........................................ 19 4.1.2两相（b,c相）短路 .......................................... 21 4.1.3两相（b相和c相）短路 接地 ................................. 23 4.1.4正序等效定则 ............................................... 25 4.2不对称故障的计算 ................................................. 26
4.2.1不对称故障的计算原理框图 ................................... 26 4.2.2 故障口电流与网络节点电压的计算 ............................. 27
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