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I摘要随着科技的进步和经济的不断发展，我国用电量需求越来越大。各地区和城镇的供电系统容量呈逐年递增的趋势，大容量的发电机组也在不断的增加。电力系统中，同步发电机是最为核心的部分，发电机是否能长期稳定的运行对于整个电力系统的安全来说起着决定性的作用。由于发电机在设计和制造过程中，不可避免的会存在一定的问题，因此发电机投入使用之前应该先按照规定进行相关的电气试验，以防止带有故障的发电机被投入使用。发电机长期不停地运行的过程中热、磁、电、摩擦、震动等因素都会给发电机带来潜在的危害，大容量发电机复杂的内部结构给其故障检测和继电保护都带来了极大的挑战。人们对电网的稳定性和安全性的要求越来越高，传统的电气故障检测和继电保护不能满足现代电力系统的需求，因此亟需深入地研究同步发电机的故障检测方法，研究在线检测电网中发电机的电气量的方法和研究电网中大型发电机进行继电保护。本论文首先对同步发电机的进行了研究，了解同步发电机的现场实际运用状况，发现越来越多的大容量发电机在电力系统中被投入使用，然而现在国内几乎没有针对大型同步发电机完整的从故障试验到继电保护的研究，本论文结合大型同步发电机的特点，根据同步发电机的内部物理结构，数学模型以及工作原理，对同步发电机进行了故障分析，并详细对定子绝缘故障和转子绕组匝间短路的检测方法进行了介绍。在分析发电机故障成因和现象的基础上，设计出一套在线监测系统，包括了硬件结构部分和软件设计部分，该监测系统能够实时对电力系统中发电机的各个重要电气量进行检测。论文还对电力系统中大型发电机的继电保护进行了设计，包括整体保护方案的设计和主保护，接地保护的详细设计，并提出发电机主保护的优化配置方案。关键词：同步发电机故障电气试验继电保护IIAbstractWiththeadvancementoftechnologyandthedevelopmentofeconomy,China'sdemandforelectricityisgrowing.Powersupplyisincreasingeveryyearinvariousregionsandlarge-capacitygeneratorsconstantlyincreasing.Inthepowersystem,synchronousgeneratoristhemostcentralpart.Whetherthegeneratorcanbeoperatedstablyplaysadecisiveroleforsecurityoftheentirepowersystem.Thegeneratorwillbesomedamagedinthedesignandmanufacturingprocessinevitably.Therefore,thegeneratorneedtobetestsbeforeitbeputtedintousetopreventfaulty.Generatorsneedtokeeplong-timeoperationandtheheat,magnetism,electricity,friction,vibration,willcausedamagetothegenerator.Thelarge-capacitygeneratorshascomplexinternalstructure,therefore,faultdetectionandprotectionareverydifficult.Peoplehavebecomeincreasinglydemandingforstabilityandsecurityofthegrid.Thetraditionalelectricalfaultdetectionandprotectioncan’tmeettheneedsofmodernpowersystems.Therefore,studyofsynchronousgeneratorfaultdetectionmethodandlargegeneratorprotectionin-depthisveryurgent.Thispaperstudiesthesynchronousgeneratorandunderstandstheactualsituationuseofsynchronousgenerators.Thestudyfindthatmoreandmorelarge-capacitygeneratorstobeusedinthepowersystem.However,therewasalmostnocompletestudyoflargesynchronousgeneratorincludingelectricaltestandprotection.Thisstudybasedonthecharacteristicsoflargegenerators.Analysisfaultconditionsofsynchronousgeneratoraccordingtotheinternalphysicalstructure,mathematicalmodelsandprincipleofwork.ThispaperdescribesthedetectionmethodofstatorinsulationfaultandRotorwindinginter-turnshortcircuitfaultdetailedly.Asetofon-linemonitoringsystemwasdesignedinthispaper.Themonitoringsystemincludesthehardwaredesignandsoftwaredesign.Itcandetectthestatusofthegeneratorinrealtime.Italsodesignedaprotectionschemeaboutlargegenerator,includingthedesignoftheoverallprotectionscheme,groundingprotectiondesign,etc.Itpresentsanoptimizationmethodaboutgeneratormainprotectionintheendofthepaper.KeyWords:SynchronousGenerator，Fault，Electricaltest，ProtectionIII目录1.1课题背景与意义...................................................................................................11.2国内外研究现状...................................................................................................21.2.1同步发电机电气故障及试验的研究现状...................................................21.2.2同步发电机继电保护研究现状...................................................................41.4研究目标与研究内容...........................................................................................61.4.1研究目标.......................................................................................................61.4.2研究内容.......................................................................................................62.1同步发电机的基本理论.......................................................................................82.1.1同步发电机的分类.......................................................................................82.1.2同步发电机物理模型...................................................................................82.1.3同步发电机工作原理...................................................................................92.2同步发电机的电气故障现象及原因分析.........................................................112.3同步发电机运行特性测试.................................................................................112.3.1空载特性试验.............................................................................................122.3.2短路特性试验.............................................................................................132.3.3负载特性试验.............................................................................................132.4定子绕组绝缘测试.............................................................................................142.4.1定子绕组介质损耗测试.............................................................................142.4.2定子绕组局部放电测试.............................................................................152.5转子绕组匝间短路测试.....................................................................................162.6STC-5型同步发电机电气试验测试及分析......................................................162.6.1STC-5型同步发电机额定参数..................................................................16摘要..............................................................................................................................