高压输电线路故障定位的研究

摘要I摘要如何快速、精确地实现线路故障点的确定是故障测距的基本任务，是电力系统继电保护领域的一个重要研究课题。输电线路担负着传送电能的重要任务，是电力系统的经济命脉，其故障直接威胁到电力系统的安全运行。故障测距根据不同的故障特征迅速准确地测定故障点的位置，从而减轻工人巡线负担，有利于及时排除故障，使线路快速恢复供电，减少因停电而造成的综合经济损失，同时还能帮助发现绝缘隐患，保证电网的安全稳定运行。高压输电线路故障定位分为单端电气量测距和双端电气量测距。单端电气量测距只利用线路一侧的电压和电流，原理上无法避免过渡电阻、两侧系统的影响，同时受线路实际参数不平衡、频变等的影响，因此其测距精度在实用中不高，难以满足工程实际的要求。双端电气量测距原理上能够克服过渡电阻、两侧系统等的影响，相比之下，精度大大提高，但是双端电气量测距受不同步采样、线路实际参数不平衡等的影响，因此在实际应用中的相对误差却比较大。本文简要介绍了MATLAB的特点，建立了基于MATLAB仿真技术的高压输电线路模型，根据该模型，利用SIMULINK数学模块实现了对双端电气量输电线路准确故障定位的数字仿真。结果表明，所建立模型简单、方便，利用MATLAB进行仿真同样具有较高精度，满足工程实际要求。关键词MATLAB/SIMULINK；高压输电线路；故障定位；双端测距燕山大学本科生毕业设计（论文）IIAbstractQuickandaccuratelocalizationoffaultsisthebasictaskoffaultlocationaswellasanimportantresearchsubjectinpowersystemrelayprotection．Transmissionlinesareresponsibleforthedeliveryofelectricenergyandtheirfaultsinfluencethesafeoperationofpowersystemdirectly．Faultpointsmustbefoundoutsoonaccordingtovariousfaultfeaturesthroughfaultlocation,andthenburdenoflinesmanislightened；faultscanbeclearedintimetorecoverpowersupplyoftransmissionlinesquickly，sothattheeconomiclossesresultedfrompowerfailureisreduced,whichcanalsohelptofindoutincipientfaultofinsulationtoensurethesafeandstableoperationofelectricnetwork．Thealgorithtmsoffaultlocationcanbedividedintosingle-terminallocationandtwo-terminallocationaccordingtomeasurementinformation.Whenthesingle-terminallocationalgorithmbasedonthefundamentalfrequencycomponentisusedtolocatethefaultposition,itisimpossibletoeliminatetheinfluenceoftransitionresistanceandequivalentimpedancevariationofremotesource．Withthedevelopmentofcommunicationandcomputernetworktechniques,two-terminallocationhasbecomemoreattractivewhichcaneliminatetheinfluenceoftransitionresistanceandequivalentimpedancevariationofremotesourceintheory．ThefeaturesofMATLABareconciselypresented.UsingMATLABsoftwareamodelofhighvoltagetransmissionlinesisbuilt.BasedonthismodelandusingSIMULINKmathematicalmodulethesimulationofaccuratefaultlocationofpowertransmissionlinesbyuseoftwoterminalselectricalquantitiesisimplemented.Simulationresultsshowthatthebuiltmodelissimpleandeasytouse,comparedwiththeEMTPsimulation,theaccuracyofsimulationresultsbyuseofMATLABaresatisfactoryandcanmeettherequirementofengineeringpractice燕山大学本科生毕业设计（论文）IIIKeywordsMATLAB/SIMULINK;Highvoltagepowertransmissionlines;Faultlocation;.Two-terminallocationIV目录摘要.......................................................................................................................IAbstract................................................................................................................II第1章绪论.........................................................................................................11.1课题背景...............................................................................................11.2高压输电线路故障测距的研究意义...................................................11.3国内外故障测距研究进展及应用现状...............................................21.4本文的主要研究内容...........................................................................5第2章故障定位.................................................................................................62.1故障分析...............................................................................................62.1.1故障特点........................................................................................62.1.2输电线路的故障类型....................................................................62.2故障定位的方法...................................................................................72.2.1故障定位的方法的分类................................................................72.2.2单端测距方法与双端测距方法的对比.......................................72.2.3对故障定位的基本要求................................................................92.3本章小结.............................................................................................10第3章双端故障测距方法...............................................................................113.1工频量双端测距算法分析..................................................................113.1.1分布参数模型..............................................................................113.1.2线路参数计算..............................................................................113.1.3双端测距算法..............................................................................123.2影响算法精度的因素..........................................................................143.3本章小结.............................................................................................14第4章MATLAB仿真实验与结果分析.........................................................164.1MATLABPSB简介与MATLAB仿真原理.....................................164.1.1MATLABPSB简介....................................................................164.1.2MATLAB仿真原理....................................................................164.2MATLAB仿真模型及参数设置........................................................17V4.2.1MATLAB仿真模型....................................................................174.2.2MATLAB仿真参数的设置......................................................194.3仿真实现....