《电力系统继电保护及应用（双语）》课件-情境一：变压器保护

电力变压器保护PowerTransformerProtection情境一：变压器保护配制Scenario1:Transformerprotectiondisposition目录页CONTENTSPAGE电力变压器的故障和异常01Faultsandabnormalconditionsofpowertransformers电力变压器保护的配置原则02Dispositionprinciplesofpowertransformerprotection变压器保护配置Transformerprotectiondisposition电力变压器的故障和异常Faultsandabnormalconditionsofpowertransformers0101电力变压器的故障和异常Faultsandabnormalconditionsofpowertransformers油箱内故障绕组的相间短路、接地短路、匝间短路;铁芯的烧损等。油箱外故障套管和引出线上发生的相间短路和接地短路。变压器的故障““FaultsoftransformerFaultsinthefueltankInterphaseshortcircuit,groundshortcircuit,ture-to-turnshortcircuitofwindings;ironcoreburning,etc.FaultsoutsidethefueltankInterphaseshortcircuitandgroundshortcircuitoccurringinbushingsandlead-outwires.01电力变压器的故障和异常Faultsandabnormalconditionsofpowertransformers变压器的不正常运行状态Abnormaloperatingstatusoftransformer1324过电流Overcurrent中性点过电压Neutralpointovervoltage过负荷Overload油面降低Oillevellowering对大容量变压器，还会发生变压器的过励磁故障Over-excitationfaultsoflarge-capacitytransformers电力变压器保护的配置原则Dispositionprinciplesofpowertransformerprotection02电力变压器保护的配置原则Dispositionprinciplesofpowertransformerprotection电力变压器保护Powertransformerprotection后备保护Backupprotection主保护Mainprotection气体保护Gasprotection

纵联差动保护或电流速断保护Longitudinaldifferentialprotectionorcurrentquick-breakprotection外部相间短路后备保护Externalinterphaseshortcircuitbackupprotection外部接地短路后备保护Externalgroundshortcircuitbackupprotection其他后备保护Otherbackupprotections01电力变压器的主保护Mainprotectionofpowertransformer气体保护Gasprotection纵联差动保护Longitudinaldifferentialprotection电流速断保护Currentquick-breakprotection01电力变压器的主保护Mainprotectionofpowertransformer反应变压器油箱内的各种故障及异常的一种保护。气体保护/Gasprotection1装设原则Installationprinciples容量在800kVA及以上的油浸式变压器和400kVA及以上的车间内油浸式变压器，应装设气体保护。Akindofprotectionthatreflectsvariousfaultsandabnormalconditionsinthetransformeroiltank.Oil-immersedtransformerswithacapacityof800kVAandaboveandoil-immersedtransformersinworkshopswithacapacityof400kVAandaboveshouldbeequippedwithgasprotection.01电力变压器的主保护Mainprotectionofpowertransformer纵联差动保护或电流速断保护/Longitudinaldifferentialprotectionorcurrentquick-breakprotection2作用Function反应变压器绕组、套管及引出线上的各种故障。Respondtovariousfaultsintransformerwindings,bushingsandlead-outwires.01电力变压器的主保护Mainprotectionofpowertransformer电流速断保护装设原则Principlesforinstallationofcurrentquick-breakprotection用于10000kVA以下，其过电流保护的动作时限大于0.5s的变压器。Fortransformersbelow10000kVA,theovercurrentprotectionoperationtimelimitshouldbegreaterthan0.5s.纵联差动保护装设原则Principlesforinstallationoflongitudinaldifferentialprotection容量为10000kVA及以上单独运行的变压器。Transformerswithcapacityof10,000kVAandaboveoperatingindividually.容量为6300kVA及以上并列运行的变压器或厂用变压器及企业中的重要变压器。Transformerswithacapacityof6300kVAandaboveoperatinginparallelorauxiliarytransformersandvitaltransformersusedinenterprises.容量为2000kVA及以上的变压器，且其电流速断保护的灵敏性不能满足要求时。Transformerswithacapacityof2000kVAandabove,thesensitivityofthecurrentquick-breakprotectionofitcannotmeettherequirements.02电力变压器的后备保护Backupprotectionforpowertransformers对于外部相间短路引起的变压器过电流，应采用下列保护1过电流保护Overcurrentprotection复合电压起动的过电流保护Overcurrentprotectionforcompoundvoltagestarting负序电流及单相式低电压起动的过电流保护Overcurrentprotectionfornegativesequencecurrentandsingle-phaselow-voltagestarting阻抗保护ImpedanceprotectionFortransformerovercurrentcausedbyexternalinterphaseshortcircuit,thefollowingprotectionshouldbeused02电力变压器的后备保护Backupprotectionforpowertransformers2对于外部接地短路引起的变压器过电流保护Fortransformerovercurrentprotectioncausedbyexternalgroundshortcircuit零序电流保护零序方向保护专用的保护装置ZerosequencecurrentprotectionZerosequencedirectionprotection例如零序过电压保护，中性点装放电间隙及零序电流保护等。SpecialprotectiondeviceForexample,zero-sequenceovervoltageprotection,neutralpointsparkgapandzero-sequencecurrentprotection,etc.02电力变压器的后备保护Backupprotectionforpowertransformers变压器的其他后备保护Otherbackupprotectionsfortransformers3过负荷保护Overloadprotection4过励磁保护Overexcitationprotection其他保护Otherprotections5油温高保护Highoiltemperatureprotection冷却器故障保护Coolerfailureprotection压力释放保护Pressurereliefprotection——

讨论Discussion请根据上述现象，判断1#主变的哪些地方可能发生了故障？为什么？某一200KV变电站的值班员，在控制室突然听到蜂鸣器响；看到后台机显示器屏幕上1#主变三侧的断路器均闪光、告警对话框提示：1#主变差动保护动作。Aattendantofa200KVsubstationsuddenlyheardabuzzersoundinthecontrolroom;hesawthe1#circuitbreakersonthreepressureswitchesoftransformerflashingonthebackgroundcomputermonitorscreen,andthealarmdialogboxprompted:1#maintransformerdifferentialprotectionoperates.Basedontheabovephenomenon,pleasedeterminewherethe#1maintransformermayhavefailed?Why?电力变压器保护PowerTransformerProtection情境二：变压器的气体保护Scenario2:Gasprotectionoftransformer目录页CONTENTSPAGE气体保护的作用及原理01Thefunctionandprincipleofgasprotection气体继电器02Gasrelay气体保护的接线03Wiringofgasprotection气体保护运行中常见问题04Commonproblemsingasprotectionoperation轻瓦斯动作后的处理05Treatmentafterlightgasoperation气体保护的作用及原理Thefunctionandprincipleofgasprotection01气体保护的作用及原理Thefunctionandprincipleofgasprotection变压器内部发生故障，故障处产生的高温会引起附近的变压器油膨胀，甚至沸腾，油内溶解的空气被逐出，形成空气泡上升。根据油箱内部故障时的这一特点，构成气体保护。当故障严重时，变压器油会迅速膨胀并产生大量的气体，此时将有剧烈的气体夹杂着油流冲向油枕的上部。1201Accordingtothischaracteristicwhenthereisaninternalfaultinthefueltank,gasprotectionisformed.Whenafaultoccursinsidethetransformer,thehightemperaturegeneratedatthefaultpointwillcausethenearbytransformeroiltoexpandorevenboil.Thedissolvedairintheoilwillbeexpelled,causingairbubblestorise.Whenthefaultissevere,thetransformeroilwillexpandrapidlyandproducealargeamountofgas.Atthistime,violentgasmixedwithoilflowwillrushtotheupperpartoftheoilpillow.气体保护的作用及原理Thefunctionandprincipleofgasprotection013气体保护分类Gasprotectionclassification重瓦斯Heavygas轻瓦斯Lightgas当变压器内部发生严重故障时，重瓦斯保护动作，瞬时动作跳开变压器的各侧断路器。当变压器油箱内轻微故障或严重漏油时，轻瓦斯保护动作，延时作用于信号。Whenaseverefaultoccursinsidethetransformer,theheavygasprotectionwilloperateandthecircuitbreakersoneachsideofthetransformerareinstantlytripped.Whenthereisaminorfaultorseriousoilleakageinthetransformertank,thelightgasprotectionwilloperateanddelaythesignal.气体保护的作用及原理Thefunctionandprincipleofgasprotection014气体保护的实现Realizationofgasprotection气体继电器Gasrelayv瓦斯继电器Buchholzrelay非电量继电器Non-electricalrelay气体继电器Gas

relay0201气体继电器的安装位置Installationpositionofgasrelay安装位置/Installationlocation安装在变压器油箱与油枕之间的连接管道上。安装要求/Installationrequirements变压器安装时，应使顶盖与水平面之间夹角应有1％～1．5％的坡度，连接管有2％～4％的升高坡度。Installedontheconnectingpipebetweenthetransformertankandtheoilpillow.Wheninstallingthetransformer,theanglebetweenthetopcoverandthehorizontalplaneshouldbeof1%to1.5%,andtheconnectingpipeshouldhaveanelevatedslopeof2%to4%.01气体继电器的安装位置Installationpositionofgasrelay瓦斯继电器的安装InstallationofBuchholzrelay瓦斯保护主要是由瓦斯继电器组成，它安装在油箱与油枕之间的管道上，如下图所示。之所以要把变压器倾斜放置，是为使变压器故障时产生的气泡不堆积在油箱内，提高瓦斯保护的灵敏性。气体继电器的安装InstallationofgasrelayBuchholzprotectionmainlyconsistsofaBuchholzrelay,whichisinstalledonthepipebetweentheoiltankandtheoilpillow,asshowninthepictureonthefollowing.ThereasonwhythetransformershouldbeplacedatanangleistopreventairbubblesgeneratedwhenthetransformerfailsfromaccumulatingintheoiltankandtoimprovethesensitivityofBuchholzprotection.气体继电器的外形/AppearanceofgasrelayQJ-15,50,80（直径）型气体继电器QJ4-50C型气体继电器02气体继电器的结构ThestructureofgasrelayQJ-15,50,80(diameter)typegasrelayQJ4-50Ctypegasrelay02气体继电器的结构Thestructureofgasrelay开口杯挡板式气体继电器结构图

瓦斯继电器结构StructurediagramofopencupbaffletypegasrelayGasrelaystructure02气体继电器的结构Thestructureofgasrelay上开口杯Upperopencup下挡板Lowerbaffle磁铁及干簧接点Magnetsandreedcontacts探针probe02气体继电器的结构Thestructureofgasrelay气孔及接线柱Airholesandterminals1).轻瓦斯保护Lightgasprotection变压器内部发生轻微故障时，变压器油分解产生的气体汇集在气体继电器上部，迫使继电器内的油面下降，开口杯露出油面，因其受到的浮力减小失去平衡而下沉，带动永久磁铁下降，当永久磁铁靠近干簧触点时，干簧触点接通，发出轻瓦斯动作信号。03气体继电器的工作原理GasrelaystructuregasrelayworkprincipleWhenaminorfaultoccursinsidethetransformer,thegasproducedbythedecompositionofthetransformeroilgathersintheupperpartofthegasrelay,forcingtheoillevelintherelaytodropandtheopencupexposesandsinksduetothereducedbuoyancyandlossofbalance,drivingthepermanentmagnetdown.Whenthepermanentmagnetisclosetothereedcontact,thecontactturnsonandsendsoutalightgasoperationsignal.2).重瓦斯保护Heavygasprotection

变压器内部发生严重故障时，油箱内产生大量气体，强大的气流伴随着油流冲击挡板，当油流的速度达到整定值时，挡板克服弹簧的反作用力向前移动，带动永久磁铁靠近干簧触点，使干簧触点闭合，发出重瓦斯跳闸脉冲，断开变压器各侧的断路器。03气体继电器的工作原理GasrelaystructuregasrelayworkprincipleWhenaseriousfaultoccursinsidethetransformer,alargeamountofgasisgeneratedinthetank,andpowerfulairflowaccompaniedbyoilflowimpactsthebaffle.Whenthespeedoftheoilflowreachesthesettingvalue,thebafflemovesforwardtoovercomethereactionforceofthespring,drivesthepermanentmagnetclosetothereedcontact,makesthereedcontactclose,emitsheavygastrippulse,andbreaksthecircuitbreakeroneachsideofthetransformer.1).轻瓦斯保护的整定与调试Settingandcommissioningoflightgasprotection动作值Operatingvalue采用气体容积大小表示整定范围通常为：250cm³～300cm³调整方法Adjustmentmethod通过移动重锤6的位置调整动作值。04气体继电器的整定与调试SettingandcommissioningofgasrelayThesettingrangeexpressedbythegasvolumeisusually:250cm³～300cm³Adjusttheoperatingvaluebymovingthepositionofcounterweight6.04气体继电器的整定与调试Settingandcommissioningofgasrelay动作值Operatingvalue采用油流速度大小表示整定范围通常为：0.6～1.5m／s调试方法Commissioningmethod通过调整调节螺杆，改变弹簧的松紧程度，调整重瓦斯的动作值，其动作值。2).重瓦斯保护的整定与调试SettingandcommissioningofheavygasprotectionThesettingrangeexpressedbytheoilflowvelocityisusually:0.6~1.5m/sSpintheadjustingscrewtochangethetightnessofthespringandtofurtheradjusttheoperatingvalueoftheheavygas.重瓦斯的试验/Heavygastest

气体继电器安装完毕，从排气口打进空气，检查轻瓦斯动作的可靠性；通过探针检查重瓦斯动作的可靠性。05重瓦斯的试验HeavygastestAfterthegasrelayisinstalled,airisblowninfromtheventtocheckthereliabilityofthelightgasoperation;thereliabilityoftheheavygasoperationischeckedthroughtheprobe.探针试验Probetest05重瓦斯的试验Testingofheavygas重瓦斯的试验/Heavygastest

气体继电器安装完毕，从排气口打进空气，检查轻瓦斯动作的可靠性；通过探针检查重瓦斯动作的可靠性。探针试验Afterthegasrelayisinstalled,airisblowninfromtheventtocheckthereliabilityofthelightgasoperation;thereliabilityoftheheavygasoperationischeckedthroughtheprobe.Probetest气体保护的接线Wiringofgasprotection03气体保护的接线Wiringofgasprotection①常规型保护的接线②与微机型保护的接口类型TYPEConventionalrelayprotectionwiringInterfacewithmicrocomputertypeprotection1常规型保护的接线Conventionalrelayprotectionwiring01常规型保护的接线Conventionalrelayprotectionwiring气体保护接线特点Characteristicsofgasprotection出口继电器必需带有自保持线圈TheoutletrelaymusthavealatchingcoilXB在必要时可将保护退出XBcandisableprotectionwhennecessaryRf起续流电阻的作用Rfactsasafreewheelingresistor01常规型保护的接线Conventionalrelayprotectionwiring1).重瓦斯保护接线/Heavygasprotectionwiring将瓦斯继电器的触点引入保护装置（非电量保护装置），经保护出口继电器和信号辅助插件，实现保护的跳闸功能和信号功能。同时还将瓦斯继电器的触点引入保护模块CPU中，供CPU检测保护动作时刻，以便记录和打印动作信息。保护连接片保护出口中间跳闸光电隔离器保护CPU记录信号中间信号重瓦斯继电器触点02气体保护与微机保护的接口InterfacebetweengasprotectionandmicrocomputerprotectionIntroducethecontactsofthegasrelayintotheprotectiondevice(non-electricalprotectiondevice),andrealizethetrippingfunctionandsignalingfunctionoftheprotectionthroughtheexitrelayandsignalauxiliaryplug-in.Atthesametime,thecontactsofthegasrelayarealsointroducedintotheprotectionmoduleCPU,allowingtheCPUtodetecttheprotectionoperationinordertorecordandprintoperationinformation.瓦斯继电器运行中常遇见的问题Problemsencounteredinoperationofgasrelay04瓦斯继电器运行中常遇见的问题Problemsencounteredinoperationofgasrelay新投运变压器，轻瓦斯动作：新变压器投运后，线圈发热，变压器油发热循环流动，将变压器内部一些空气排除，积聚在变压器上部，使变压器油面下降，造成轻瓦斯动作。1处理方法Approach将瓦斯继电器放气阀打开，排出变压器本体内气体即可。Openthebleedvalveofgasrelaytodischargethegasinthetransformer.transformernewlyputintooperation,lightgasoperation:Afterthenewtransformerisputintooperation,thecoilheatsup,andthetransformeroilheatsupandcirculates,expellingsomeairinsidethetransformer,whichaccumulatesintheupperpartofthetransformer,causingtheoillevelofthetransformertodrop,finallycausinglightgasoperation.问题2QUESTION2瓦斯继电器接线盒内进水，造成轻、重瓦斯保护动作：下雨天，瓦斯继电器接线盒封闭不严，雨水进入继电器接线盒内造成接线柱短路，使轻、重瓦斯保护动作。瓦斯继电器运行中常遇见的问题ProblemsencounteredinoperationofgasrelayWaterenteringthegasrelayterminalboxcauseslightandheavygasprotectionoperations:Onrainydays,thegasrelayterminalboxisnottightlyclosed,andrainwaterentersit,causingashortcircuitoftheterminals,furthercausinglightandheavygasprotectionoperations.问题3QUESTION3瓦斯继电器接点线破损接地，也会造成轻、重瓦斯保护动作。Ifthedamagedgasrelaycontactwireisgrounded,itwillalsocauselightandheavygasprotectionoperations.轻瓦斯动作后的处理Treatmentafterlightgasoperation05轻瓦斯动作后的处理Treatmentafterlightgasoperation瓦斯继电器动作后，应立即收集瓦斯继电器内聚积的气体，通过鉴别气体的性质，做进一步判断。一般将专用玻璃瓶倒置，使瓶口靠近瓦斯继电器的放气阀来收集气体。1ONE如果气体无色无味，且不能点燃，是油内排出空气所致Ifthegasiscolorlessandodorlessandcannotbeignited,itiscausedbyairbeingexpelledfromtheoil2TWO如果收集到的气体为黄色，且不易点燃，为木质部分出现了故障Ifthecollectedgasisyellowanddifficulttoignite,thereisafaultinthewoodenpart3THREE如果气体为淡黄色并带强烈臭味，又可燃烧，则表明是纸质部分故障Ifthegasislightyellowwithastrongodorandflammable,itindicatesthatthepaperpartisfaultyAfterthegasrelayoperates,thegasaccumulatedinthegasrelayshouldbecollectedimmediately,andfurtherjudgmentshouldbemadebyidentifyingthenatureofthegas.Generally,thespecialglassbottleisturnedupsidedownsothatthemouthofthebottleisclosetothebleedvalveofthegasrelaytocollectgas.瓦斯保护能独立的用作变压器的主保护吗？

为什么？思考题Thinkoboutit轻瓦斯动作后的处理TreatmentafterlightgasoperationCangasprotectionbeusedindependentlyasthemainprotectionofatransformer?Why?电力变压器保护PowerTransformerProtection情境三：变压器的差动保护情境四：变压器的电流速断保护Scenario3:DifferentialprotectionoftransformerScenario4:Currentquick-breakprotectionoftransformer目录页CONTENTSPAGE情境三：变压器的差动保护Scenario3:Differentialprotectionoftransformer变压器纵联差动保护的基本原理Basicprincipleoftransformerlongitudinaldifferentialprotection1变压器纵差保护的特殊问题Specialproblemsoftransformerdifferentialprotection2变压器纵联差动保护的构成及原理Thecompositionandprincipleoftransformerlongitudinaldifferentialprotection3情境四：变压器的电流速断保护Scenario4:Currentquick-breakprotectionoftransformer变压器电流速断保护的装设原则Installationprinciplesoftransformercurrentquick-breakprotection1变压器电流速断保护的整定原则Settingprinciplesoftransformercurrentquick-breakprotection2情境三Scenario3变压器的差动保护Differentialprotectionoftransformer变压器纵联差动保护的基本原理Basicprincipleoftransformerlongitudinaldifferentialprotection01变压器纵联差动保护的基本原理Basicprincipleoftransformerlongitudinaldifferentialprotection1正常及外部故障时Duringnormaloperationandexternalfaults参考公式Referenceformula

2内部故障时Incaseofinternalfailure参考公式Referenceformula变压器纵联差动保护的基本原理Basicprincipleoftransformerlongitudinaldifferentialprotection变压器纵差保护的特殊问题Specialproblemsoftransformerdifferentialprotection0201因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside1常规型变压器差动保护的相位补偿Phasecompensationofconventionaltransformerdifferentialprotection1).因相位不同而产生的不平衡电流2).相位补偿（左图所示）3).相位补偿后，电流互感器变比的选择UnbalancedcurrentduetodifferentphasesPhasecompensation(shownontheleft)Afterphasecompensation,theselectionofcurrenttransformerratio01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside设Assume变压器两侧额定电流分别为：theratedcurrentsonbothsidesofthetransformerare:变压器

侧，电流为变压器Y侧，电流为变压器三角形侧电流互感器的变比为采用相位补偿后，取Afteradoptingphasecompensation,take变压器星形侧电流互感器的变比为或按下列条件选择TA变比3).相位补偿后，电流互感器变比的选择Afterphasecompensation,theselectionofcurrenttransformerratio则then若取IftakeOntheYsideofthetransformer,thecurrentisOnthesideofthetransformer,thecurrentisthetransformationratioofthecurrenttransformeronthedeltasideofthetransformerasthetransformationratioofthecurrenttransformeronthestarsideofthetransformerasorselectTAtransformationratioaccordingtothefollowingconditions01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside例ExampleY侧Y

Side侧SideTA接线方式TAWiringY计算变比Calculatetransformationratio标准变比Standardratio二次电流Secondarycurrent不平衡电流Unbalancedcurrent01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside2微机型变压器差动保护的相位补偿及电流平衡调整Phasecompensationandcurrentbalanceadjustmentofmicrocomputertypetransformerdifferentialprotection当各侧电流互感器都采用星形接线时，利用软件对变压器星形侧电流进行相位和幅值的补偿。Whenthecurrenttransformersoneachsideadoptstarconnection,softwareisusedtocompensatethephaseandamplitudeofthecurrentonthestarsideofthetransformer.01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside设Assume星形侧三相电流采样值分别为：Thethree-phasecurrentsamplingvaluesofthestarsidearerespectively则：用作差动保护计算的三相电流为Then:thethree-phasecurrentusedfordifferentialprotectioncalculationis1).相位补偿Phasecompensation01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside2).幅值补偿Amplitudecompensation电流平衡调整系数Currentbalanceadjustmentcoefficient1计算变压器各侧的一次额定电流：Calculatetheprimaryratedcurrentforeachsideofthetransformer2计算变压器各侧TA二次计算电流：CalculatethesecondarycalculationcurrentofTAoneachsideofthetransformer3计算电流平衡调整系数：Calculatethecurrentbalanceadjustmentcoefficient01因各侧相位不同产生的不平衡电流及相位补偿Unbalancedcurrentandphasecompensationduetodifferentphaseoneachside高压侧平衡系数为：Thebalancecoefficientofthehigh-voltagesideis中压侧平衡系数为：Thebalancecoefficientofthemedium-voltagesideis低压侧平衡系数为：Thebalancecoefficientofthelow-voltagesideis设以高压侧二次额定电流为基准，则2).幅值补偿AmplitudecompensationAssumingthatthesecondaryratedcurrentofthehigh-voltagesideisusedasthebasis,then02变压器励磁涌流的影响及减小影响的措施Theinfluenceoftransformerexcitationinrushcurrentandthemeasurestoreducetheinfluence变压器的励磁涌流是指在变压器空载合闸或者外部故障切除后电压恢复时，可能出现的较大的励磁电流。1励磁涌流的影响EffectofinrushcurrentTheinrushcurrentofthetransformerreferstothelargeexcitationcurrentthatmayoccurwhenthetransformerisswitched-inwithoutloadorthevoltagerecoversaftertheexternalfaultisremoved.02变压器励磁涌流的影响及减小影响的措施Theinfluenceoftransformerexcitationinrushcurrentandthemeasurestoreducetheinfluence铁芯中的磁通不能突变2产生励磁涌流的原因CausesofinrushcurrentThemagneticfluxintheironcorecannotchangesuddenly铁芯中出现一个暂态磁通Atransientmagneticfluxappearsintheironcore铁芯中的磁通将达到最大值Themagneticfluxintheironcorewillreachitsmaximumvalue铁芯严重饱和，励磁电流将剧烈增大Theironcoreisseriouslysaturatedandtheexcitationcurrentwillincreasedramatically.02变压器励磁涌流的影响及减小影响的措施Theinfluenceoftransformerexcitationinrushcurrentandthemeasurestoreducetheinfluence3励磁涌流的特点Characteristicsofinrushcurrent包含有非周期分量Containsnon-periodiccomponents幅值大，但衰减快Largeamplitude,butfastdecay包含有高次谐波分量Containshighharmoniccomponents波形之间有间断Therearebreaksbetweenwaveforms02变压器励磁涌流的影响及减小影响的措施Theinfluenceoftransformerexcitationinrushcurrentandthemeasurestoreducetheinfluence采用具有速饱和铁芯的差动继电器Adifferentialrelaywitharapidlysaturableironcoreisused.采用二次谐波制动的差动保护Differentialprotectionwithsecondharmonicbrakingisadopted.利用间断角闭锁的差动保护Differentialprotectionlockedbydeadangle.4减小励磁涌流影响的措施Measurestoreducetheimpactofinrushcurrent03各侧电流数值不等引起的不平衡电流Unbalancedcurrentscausedbyunequalvaluesofcurrentsateachside1计算变比与标准变比不完全符合Thecalculatedtransformationratiodoesnotcompletelymatchthestandardtransformationratio如like整定计算时应考虑平衡系数thebalancecoefficientshouldbeconsideredwhenperformingthesettingcalculation如like2两侧TA的型号不同ThemodelsofTAonbothsidesaredifferent型号不同Differentmodels整定计算时考虑同型系数Thehomogeneouscoefficientsarecommonlytakenduringsettingcalculation型号相同Samemodel03各侧电流数值不等引起的不平衡电流Unbalancedcurrentscausedbyunequalvaluesofcurrentsateachside设Assume变压器由115KV改在110KV抽头位置transformerchangedfrom115KVto110KVtapposition3变压器带负荷调整分接头Transformerwithloadtapchanger则then整定计算时应考虑因带负荷调压所引起的相对误差therelativeerrorcausedbyon-loadvoltageregulationshouldbeconsideredduringthesettingcalculation变压器纵联差动保护的构成及原理Thecompositionandprincipleoftransformerlongitudinaldifferentialprotection0301比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking1和差式比率制动的差动保护Differentialprotectionofsum-differentialratiobraking1).对于双绕组变压器Fortwowindingtransformer正常及外部故障时Duringnormaloperationandexternalfaults01比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking对于双绕组变压器Fortwowindingtransformer内部故障时Incaseofinternalfailure01比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking双绕组变压器Twowindingtransformer差动保护的动作条件Operationconditionsofdifferentialprotection动作分量operationcomponent制动分量

brakingcomponent取TAKE01比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking2).对于三绕组变压器

Forthreewindingtransformer动作电流Operatingcurrent制动电流Brakingcurrent方法1/Method1取变压器各侧电流中最大的电流。Takethemaximumcurrentamongthecurrentsoneachsideofthetransformer.01比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking制动电流Brakingcurrent方法2

/Method2取三个制动电流量中的最大值。动作电流OperatingcurrentTakethemaximumvalueamongthethreebrakingcurrents.01比率制动的纵差保护Thelongitudinaldifferentialprotectionoftheratiobraking3).比率制动式差动保护的动作特性Operatingcharacteristicsofratiobrakingdifferentialprotection动作判据Operationcriterion02励磁涌流鉴别的原理Theprincipleofmagnetizinginrushcurrentidentification1二次谐波闭锁原理Secondaryharmonicblockingprinciple采用：三相差动电流中二次谐波电流与基波电流的比值，作为励磁涌流闭锁的判据。闭锁判据为Thelockingcriterionis整定范围为0.1～0.3，通常取0.15Use:theratioofthesecondaryharmoniccurrentandthefundamentalcurrentinthethree-phasedifferentialcurrentasthecriterionforinrushcurrentblocking.thesettingrangeis0.1~0.3,usually0.1502励磁涌流鉴别的原理Theprincipleofmagnetizinginrushcurrentidentification2间断角识别原理Deadangleidentificationprinciple根据：励磁涌流波形有间断角的特点。判据如下：Thecriteriaareasfollows通常取：Usuallytake采用：波形比较技术将变压器的励磁涌流和故障电流分开。Accordingto:thedeadangleofinrushcurrentwaveform.Use:waveformcomparisontechnologytoseparatethetransformer'sinrushcurrentandfaultcurrent.03差动速断保护Differentialquickbreakprotection只要任一相差动电流大于差动速断的整定值，保护瞬时动作。Aslongasthedifferentialcurrentofanyphaseisgreaterthanthesettingvalueofdifferentialquick-break,theprotectionwilloperateinstantaneously.动作判据为Theoperationcriterionis其中where为变压器差动电流isthetransformerdifferentialcurrent为差动电流速断保护定值isthesettingvaluefordifferentialcurrentquick-breakprotection定义Definition当任一相差动电流大于0.1In（TA二次额定电流）时，启动TA断线判别程序。判据Criterion本侧三相电流中一相无电流，而本侧其它两相和另一侧各相电流与启动前电流相等，判为是TA断线。04电流互感器断线监视CurrenttransformerdisconnectionmonitoringWhenthedifferentialcurrentofanyphaseisgreaterthan0.1In(secondaryratedcurrentTA),theTAdisconnectionidentificationprogramisstarted.Oneofthethree-phasecurrentsonthissidehasnocurrent,buttheothertwophasesonthissideandeachphasecurrentontheothersideareequaltothecurrentbeforestarting.ItisdeterminedthattheTAisdisconnected.05差动保护程序框图Differentialprotectionprogramdiagram图8－11差动保护程序框图TA断线信号告警闭锁保护差动保护程序框图Differentialprotectionprogramdiagram因各侧相位不同产生的不平衡电流及相位补偿比率制动的纵差保护小结Summary1变压器纵差保护的特殊问题Specialproblemsoftransformerdifferentialprotection2微机型变压器差动保护MicrocomputertypetransformerdifferentialprotectionUnbalancedcurrentandphasecompensationduetodifferentphasesoneachside变压器励磁涌流的影响及减小影响的措施Theimpactoftransformerinrushcurrentandmeasurestoreducetheimpact各侧电流数值不等引起的不平衡电流UnbalancedcurrentcausedbyunequalcurrentvaluesoneachsideRatiobrakingdifferentialprotection励磁涌流鉴别的原理Theprincipleofidentificationofinrushcurrent差动速断保护Differentialquickbreakprotection电流互感器断线监视Currenttransformerdisconnectionmonitoring情境四Scenario4变压器的电流速断保护Currentquick-breakprotectionoftransformer01变压器电流速断保护的装设原则Installationprinciplesoftransformercurrentquick-breakprotection10000KVA以下的小容量变压器，当过电流保护的动作时限大于0.5秒且灵敏度满足要求时，在电源侧装设电流速断保护。装设原则/Installationprinciples电源侧为直接接地系统时，保护采用完全星形接线。接线方式1Wiringmethod1电源侧如为非直接接地系统，采用两相不完全星形接线。接线方式2Wiringmethod2Forsmall-capacitytransformersbelow10,000KVA,whentheoperationtimelimitofover-currentprotectionisgreaterthan0.5secondsandthesensitivitymeetstherequirements,currentquick-breakprotectionisinstalledonthepowersupplyside.Whenthepowersupplysideisadirectlygroundedsystem,theprotectionadoptscompletestarconnection.Ifthepowersupplysideisanindirectlygroundedsystem,usetwo-phaseincompletestarconnection.02变压器电流速断保护的整定原则Settingprinciplesoftransformercurrentquick-breakprotection动作电流的整定值/Settingvalueofoperatingcurrent

躲过变压器空载投入时的励磁涌流，根据实践经验一般取动作电流大于3～5倍的变压器额定电流。躲过变压器负荷侧母线上k1点短路时，流过保护的最大短路电流计算。以下两个条件计算，选择其中较大者Calculatethefollowingtwoconditions,choosethelargeroneCalculationofthemaximumshort-circuitcurrentflowingthroughtheprotectionwhenavoidingtheshortcircuitatpointk1ontheloadsidebusbarofthetransformer.Theinrushcurrentthatavoidsthetransformerputtingintooperationwithoutload,basedonpracticalexperience,theoperatingcurrentisgenerallysettobeg