《电力系统继电保护及应用》课件-变压器保护

变压器保护配置TransformerProtectionConfiguration微课WKE知识点：变压器保护配置专业：电气自动化技术单元：变压器保护Knowledgepoint:TransformerprotectionconfigurationMajor:ElectricalautomationtechnologyUnit:Transformerprotection配置原则Configurationprinciples变压器故障分为油箱内故障和油箱外故障，油箱内故障时，除了变压器各侧电流、电压变化外，油箱内的油、气、温度等非电量也会发生变化。因此，作为变压器的保护分为电量保护和非电量保护。01对于220kV及以上电压等级的变压器，应配置双套主保护、双套后备保护、一套非电量保护，并保证两套主保护完全独立，即交流电压电流回路、直流电源回路、出口跳闸回路完全独立。Configurationprinciple观看视频WatchthevideoTransformerfaultsincludefaultsinsidethetankandfaultsoutsidethetank.Whenthereisafaultinsidethetank,inadditiontothechangesincurrentandvoltageoneachsideofthetransformer,theoil,gas,temperatureandothernon-electricquantitiesinthetankwillalsochange.Therefore,theprotectionofthetransformerisdividedintoelectricalquantityprotectionandnon-electricalquantityprotection.Fortransformerswithvoltagelevelsof220kVandabove,theyshouldbeequippedwithtwosetsofmainprotection,twosetsofbackupprotection,andonesetofnon-electricityquantityprotection,andensurethatthetwosetsofmainprotectionarecompletelyindependent,thatis,theACvoltageandcurrentloop,DCpowerloop,andoutlettrippinglooparecompletelyindependent.一.变压器的主保护变压器油对变压器有绝缘和冷却作用。当变压器油箱内故障时，在故障电流和故障点电弧的作用下，变压器油（和其他绝缘材料）会因受热而分解，产生大量气体。气体排出的多少以及排出速度，与变压器故障的严重程度有关。利用这种气体来实现的保护称为瓦斯保护。瓦斯保护/gasprotection1对于容量在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，应装设瓦斯保护。瓦斯保护分为轻瓦斯保护和重瓦斯保护，轻瓦斯保护动作于信号，重瓦斯保护动作跳开变压器各电源侧的断路器。MainprotectionoftransformerTransformeroilhasaninsulatingandcoolingeffectonthetransformer.Whenthereisafaultinthetransformeroiltank,undertheactionoffaultcurrentandarcatthefaultpoint,thetransformeroil(andotherinsulatingmaterials)willdecomposeduetoheat,producingalargeamountofgas.Theamountandspeedofgasdischargedarerelatedtotheseverityofthetransformerfailure.Theprotectionachievedbyusingthisgasiscalledgasprotection.Foroil-immersedtransformerswithacapacityof800kVAandaboveandoil-immersedtransformersinworkshopswithacapacityof400kVAandabove,gasprotectionshouldbeinstalled.Gasprotectionisdividedintolightgasprotectionandheavygasprotection.Lightgasprotectionactsonthesignal,andheavygasprotectionactsonthecircuitbreakersoneachpowersupplysideofthetransformer.一.变压器的主保护Mainprotectionoftransformer变压器油对变压器有绝缘和冷却作用。当变压器油箱内故障时，在故障电流和故障点电弧的作用下，变压器油（和其他绝缘材料）会因受热而分解，产生大量气体。气体排出的多少以及排出速度，与变压器故障的严重程度有关。利用这种气体来实现的保护称为瓦斯保护。瓦斯保护/gasprotection1对于容量在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，应装设瓦斯保护。瓦斯保护分为轻瓦斯保护和重瓦斯保护，轻瓦斯保护动作于信号，重瓦斯保护动作跳开变压器各电源侧的断路器。Transformeroilhasaninsulatingandcoolingeffectonthetransformer.Whenthereisafaultinthetransformeroiltank,undertheactionoffaultcurrentandarcatthefaultpoint,thetransformeroil(andotherinsulatingmaterials)willdecomposeduetoheat,producingalargeamountofgas.Theamountandspeedofgasdischargedarerelatedtotheseverityofthetransformerfailure.Theprotectionachievedbyusingthisgasiscalledgasprotection.Foroil-immersedtransformerswithacapacityof800kVAandaboveandoil-immersedtransformersinworkshopswithacapacityof400kVAandabove,gasprotectionshouldbeinstalled.Gasprotectionisdividedintolightgasprotectionandheavygasprotection.Lightgasprotectionactsonthesignal,andheavygasprotectionactsonthecircuitbreakersoneachpowersupplysideofthetransformer.一.变压器的主保护差动保护或电流速断保护Differentialprotectionorcurrentquick-breakprotection2容量为10000kVA以上单独运行的变压器；容量为6300kVA以上，并列运行的变压器或发电厂厂用变压器及企业中的重要变压器；容量在2000kVA以上的变压器，当其电流速断保护的灵敏性不能满足要求时。Fortransformerswithacapacityabove2000kVA,whenthesensitivityofthecurrentquick-breakprotectioncannotmeettherequirements.电流速断保护用于10000kVA以下的变压器。Currentquick-breakprotectionisusedfortransformersbelow10000kVA.为防止变压器绕组、套管及引出线上的故障，根据变压器容量的不同，应装设纵联差动保护或电流速断保护。Topreventfaultsinthetransformerwindings,bushings,andleadwires,basedonthedifferentcapacitiesoftransformers,longitudinaldifferentialprotectionorinstantaneousovercurrentprotectionshouldbeinstalled.变压器纵联差动保护或电流速断保护各保护动作后，均跳开变压器各电源侧的断路器。Aftereachprotectionoperationofthetransformerlongitudinaldifferentialprotectionorcurrentquick-breakprotection,thecircuitbreakersoneachpowersupplysideofthetransformeraretripped.纵联差动保护用于以下条件的变压器：Longitudinaldifferentialprotectionisusedfortransformersunderthefollowingconditions:MainprotectionoftransformerTransformersoperatingindividuallywithacapacityof10,000kVAorabove;Transformerswithacapacityof6300kVAorabove,operatinginparallelortransformersforpowerplantsandimportanttransformersinenterprises;二.变压器的后备保护防止变压器的外部短路并作为主保护的后备保护ProtectsagainstexternalshortcircuitsofthetransformerandservesasbackupprotectiontothemainprotectionBackupprotectionoftransformer相间短路的后备保护Backupprotectionforinterphaseshortcircuit1过电流保护Overcurrentprotection复合电压起动的过电流保护Overcurrentprotectionforcompositevoltagestarting负序电流及单相式低电压起动的过电流保护Negativesequencecurrentandovercurrentprotectionforsingle-phaselow-voltagestarting阻抗保护Impedanceprotection二.变压器的后备保护该保护的国网标准化配置为：Thestandardizedconfigurationofthenationalnetworkforthisprotectionis:在变压器低压侧配置二段复压起动过流保护，保护动作后一时限跳分段断路器，二时限跳本侧主变断路器。在变压器高压侧和中压侧配置三段复压起动过流保护，保护动作后一时限跳母联断路器，二时限跳本侧断路器，三时限跳主变各侧断路器；在当前的微机变压器保护装置中，最常用的是复合电压起动的过电流保护。Amongthecurrentmicrocomputertransformerprotectiondevices,themostcommonlyusediscompositevoltagestartingovercurrentprotection.BackupprotectionoftransformerThree-stagecompoundvoltagestartingovercurrentprotectionisconfiguredonthehigh-voltagesideandmedium-voltagesideofthetransformer.Aftertheprotectionisactivated,thebustiecircuitbreakerwillbetrippedinonetimelimit,thecircuitbreakeronthissidewillbetrippedinthetwotimelimit,andthecircuitbreakersoneachsideofthemaintransformerwillbetrippedinthreetimelimits;Atwo-stagecompoundvoltagestartingovercurrentprotectionisconfiguredonthelow-voltagesideofthetransformer.Aftertheprotectionisactivated,thesectioncircuitbreakerwilltripinonetimelimitandthemaintransformercircuitbreakeronthissidewilltripinthetwotimelimit.二.变压器的后备保护对于中性点直接接地的变压器，为防止外部接地短路引起变压器过电流，应装设零序电流保护。Fortransformerswhoseneutralpointsaredirectlygrounded,zero-sequencecurrentprotectionshouldbeinstalledtopreventexternalgroundshortcircuitsfromcausingovercurrentinthetransformer.自耦变压器和高、中压侧中性点都直接接地的三绕组变压器，当有选择性要求时，应装设零序方向元件。Theautotransformerandthethree-windingtransformerinwhichtheneutralpointsofthehighandmediumvoltagesidesaredirectlygroundedshouldbeequippedwithzerosequencedirectionalcomponentswhenselectivityisrequired.对于中性点可能接地也可能不接地运行的每台变压器，其接地保护需配置两套。中性点接地运行方式时的接地保护通常采用两段式零序过电流保护，而中性点不接地运行方式时的接地保护，通常采用零序过电压保护和间隙零序电流保护。接地短路的后备保护Backupprotectionforgroundshortcircuit2BackupprotectionoftransformerForeachtransformerwhoseneutralpointmayormaynotbegrounded,twosetsofgroundingprotectionarerequired.Thegroundprotectionwhentheneutralpointisgroundedusuallyusestwo-stagezerosequenceovercurrentprotection,whilethegroundprotectionwhentheneutralpointisnotgroundedusuallyuseszerosequenceovervoltageprotectionandgapzerosequencecurrentprotection.二.变压器的后备保护变压器长期过负荷运行时，绕组会因发热而受到损伤Whenthetransformerisoverloadedforalongtime,thewindingswillbedamagedduetoheat.对400kVA以上的变压器，当数台并列运行，或单独运行并作为其他负荷的备用电源时，应根据可能过负荷的情况，装设过负荷保护。Fortransformersabove400kVA,whenseveraltransformersoperateinparalleloroperateindividuallyandserveasbackuppowerforotherloads,overloadprotectionshouldbeinstalledbasedonpossibleoverloadconditions.过负荷保护接于一相电流上，并延时作用于信号。对于无经常值班人员的变电所，必要时过负荷保护可动作于自动减负荷或跳闸。Theoverloadprotectionisconnectedtoonephasecurrentandactsonthesignalwithadelay.Forsubstationswithoutregularpersonnelonduty,overloadprotectioncanoperatetoautomaticallyreduceloadortripwhennecessary.过负荷保护Overloadprotection3Backupprotectionoftransformer二.变压器的后备保护对频率降低和电压升高而引起变压器过励磁时，励磁电流急剧增加，铁芯及附近的金属构件损耗增加，引起高温。长时间或多次反复过励磁，将因过热而使绝缘老化。Whenthefrequencydecreasesandthevoltageincreases,causingoverexcitationofthetransformer,theexcitationcurrentincreasessharply,andthelossoftheironcoreandnearbymetalcomponentsincreases,causinghightemperatures.Repeatedoverexcitationforalongtimeormultipletimeswillcauseinsulationagingduetooverheating.电压为500kV及以上的变压器，应装设过励磁保护，在变压器允许的过励磁范围内，保护作用于信号，当过励磁超过允许值时，可动作于跳闸。负荷保护。Transformerswithvoltagesof500kVandaboveshouldbeequippedwithoverexcitationprotection.Withintheallowableoverexcitationrangeofthetransformer,theprotectionactsonthesignal.Whentheoverexcitationexceedstheallowablevalue,itcanoperatetotrip.Loadprotection.过励磁保护Overexcitationprotection4Backupprotectionoftransformer二.变压器的后备保护压力保护也是变压器油箱内部故障的主保护，其作用原理与重瓦斯保护基本相同，但它是反应变压器油的压力。Pressureprotectionisalsothemainprotectionforinternalfaultsinthetransformeroiltank.Itsworkingprincipleisbasicallythesameasheavygasprotection,butitreflectsthepressureofthetransformeroil.压力释放装置由弹簧和触点构成，置于变压器本体油箱上部。当变压器内部故障时，温度升高，油膨胀分解造成压力升高，弹簧动作带动继电器动触点，使触点闭合，切除变压器。Thepressurereliefdeviceconsistsofaspringandacontactpointandisplacedontheupperpartoftheoiltankofthetransformerbody.Whenthereisaninternalfaultinthetransformer,thetemperaturerises,theoilexpandsanddecomposes,causingthepressuretorise.Thespringoperationdrivestherelaymovingcontacts,closingthecontactsandcuttingoffthetransformer.其他非电量保护Othernon-electricquantityprotection5A.压力保护Pressureprotection压力释放阀/PressurereliefvalveBackupprotectionoftransformer二.变压器的后备保护强油循环风冷和强油循环水冷变压器，当冷却系统故障切除全部冷却器时，允许带额定负载运行20min。Strongoilcirculationair-coolingandstrongoilcirculationwater-coolingtransformersareallowedtooperatewithratedloadfor20minuteswhenthecoolingsystemfailsandallcoolersareremoved.如20min后顶层油温尚未达到75℃，则允许上升到75℃，但在这种状态下运行的最长时间不得超过1小时。Ifthetopoiltemperaturehasnotreached75℃after20minutes,itisallowedtoriseto75℃,butthemaximumoperatingtimeinthisstateshallnotexceed1hour.其他非电量保护Othernon-electricquantityprotection5B.冷却器全停/

CoolerfullystoppedBackupprotectionoftransformer二.变压器的后备保护当变压器温度升高时，温度保护动作发出告警信号。Whenthetemperatureofthetransformerrises,thetemperatureprotectionoperationsendsanalarmsignal.油位异常保护是反应油枕内油位异常的保护，运行时，变压器漏油或者其他原因使油位降低时，油位保护动作，发出告警信号。Theabnormaloillevelprotectionisaprotectionthatreflectstheabnormaloillevelintheoilconservator.Duringoperation,whenthetransformerleaksoilortheoilleveldecreasesduetootherreasons,theoillevelprotectionwilloperateandsendoutanalarmsignal.C.油温、油位异常保护OiltemperatureandoillevelabnormalityprotectionBackupprotectionoftransformer其他非电量保护Othernon-electricquantityprotection5感谢您的观看与聆听微课WKE知识点：变压器保护配置专业：电气自动化技术单元：变压器保护ThankyouforwatchingandlisteningKnowledgepoint:TransformerprotectionconfigurationMajor:ElectricalautomationtechnologyUnit:Transformerprotection01Configurationprinciple配置原则Configurationprinciples变压器故障分为油箱内故障和油箱外故障，油箱内故障时，除了变压器各侧电流、电压变化外，油箱内的油、气、温度等非电量也会发生变化。因此，作为变压器的保护分为电量保护和非电量保护。01对于220kV及以上电压等级的变压器，应配置双套主保护、双套后备保护、一套非电量保护，并保证两套主保护完全独立，即交流电压电流回路、直流电源回路、出口跳闸回路完全独立。Configurationprinciple观看视频WatchthevideoTransformerfaultsincludefaultsinsidethetankandfaultsoutsidethetank.Whenthereisafaultinsidethetank,inadditiontothechangesincurrentandvoltageoneachsideofthetransformer,theoil,gas,temperatureandothernon-electricquantitiesinthetankwillalsochange.Therefore,theprotectionofthetransformerisdividedintoelectricalquantityprotectionandnon-electricalquantityprotection.Fortransformerswithvoltagelevelsof220kVandabove,theyshouldbeequippedwithtwosetsofmainprotection,twosetsofbackupprotection,andonesetofnon-electricityquantityprotection,andensurethatthetwosetsofmainprotectionarecompletelyindependent,thatis,theACvoltageandcurrentloop,DCpowerloop,andoutlettrippinglooparecompletelyindependent.瓦斯保护微课WKEGasProtection知

识

点：瓦斯保护原理专 业：电力类相关专业单 元：变压器保护Knowledgepoint:GasprotectionprincipleMajor:Electricpowerrelated

majorsUnit:Transformer

protection瓦斯保护

Gas

Protection变压器的瓦斯保护用来反应油浸式变压器油箱内的各种故障。当变压器油箱内故障时，瓦斯保护有着独特的、其它保护所不具备的优点，如当变压器发生严重漏油、绕组断线故障或绕组匝间短路产生的短路电流值不足以使其它保护动作时，只有瓦斯保护能够灵敏动作发出信号或跳闸。Thegasprotectionofthetransformerisusedtorespondtovariousfaultsintheoil-immersedtransformertank.Whenthereisafaultinthetransformertank,gasprotectionhasuniqueadvantagesthatotherprotectionsdonothave.Forexample,whenthereisaseriousoilleakageinthetransformer,awindingdisconnectionfault,orashortcircuitbetweenwindingturns,theshortcircuitcurrentvalueisnotenoughforotherprotectionstooperate,andonlythegasprotectioncanrespondsensitivelytosendasignalor

trip.所以变压器的瓦斯保护是大型变压器内部故障的重要保护Therefore,thegasprotection

oftransformersisanimportantprotectionforinternalfaultsoflarge

transformers.01瓦斯继电器Gasrelay02瓦斯继电器的整定Settingofgas

relay03轻瓦斯发信后的处理Processingaftersendinglightgas

signal瓦斯继电器Gas

relay01/

ONE瓦斯继电器Gas

relay瓦斯继电器是实现瓦斯保护的主要元件。Gasrelayisthemaincomponentforgas

protection.图1A：法兰盘连接的壳体Figure1A:Housingwith

flangeconnection图1B：螺纹连接的壳体Figure1B:Threaded

housing瓦斯继电器Gas

relay瓦斯继电器安装在变压器油箱与油枕之间的连接管道中。Thegasrelayisinstalledintheconnectingpipebetweenthetransformertankandtheoil

conservator瓦斯继电器Gas

relay瓦斯保护Gas

protection分为Fall

into轻瓦斯保护Lightgas

protection重瓦斯保护Heavygas

protection在我国电力系统中应用的瓦斯继电器大多是开口杯挡板式结构。MostofthegasrelaysusedinChina'spowersystemsareopencupbafflestructures.瓦斯继电器的整定Settingofgas

relay02/

TWO瓦斯继电器的整定250cm3～300cm3>>>Settingofgas

relay01.

轻瓦斯保护整定Settingoflightgas

protection动作值：采用气体容积大小表示Operationvalue:expressedbygas

volume整定范围通常为Thesetting

rangeis

usually调整方法：通过移动重锤的位置，调整动作值。Adjustmentmethod:Adjusttheoperationvaluebymovingthepositionofthe

weight.瓦斯继电器的整定调整方法：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。Adjustmentmethod:Byadjustingthescrew,changethetightnessofthespringandadjusttheoperationvalueofthe

heavygas.0.6～1.5m／s>>>Settingofgas

relay02.

重瓦斯保护整定Settingofheavygas

protection动作值：采用油流速度大小表示Operationvalue:Expressedbyoilflow

velocity整定范围通常为Thesetting

rangeis

usually瓦斯继电器的整定Settingofheavygas

protection瓦斯保护的接线Gasprotection

wiring当变压器内部发生轻微故障时，轻瓦斯保护动作，瓦斯继电器KG的上触点（KG1）闭合，作用于预告信号Whenaminorfaultoccursinsidethetransformer,the

lightgasprotectionoperates,andtheuppercontact(KG1)ofthegasrelayKGcloses,operatingonthewarning

signal当发生严重故障时，重瓦斯保护动作，下触点（KG2）闭合，经信号继电器KS作用于中间继电器KCO，发出报警信号，同时将断路器跳闸。Whenaseriousfaultoccurs,theheavygasprotectionoperates,thelowercontact(KG2)isclosed,andthesignalrelayKSoperatesontheintermediaterelayKCO,sendinganalarmsignalandtrippingthecircuitbreakeratthesame

time.轻瓦斯发信后的处理TreatmentofLightGasafterLetter

Delivery03/

THREE轻瓦斯发信后的处理TreatmentofLightGasafterLetter

Delivery轻瓦斯发信时，值班人员必须立即检查动作原因Whenalightgassignalissent,thepersonondutymustimmediatelycheckthereasonforthe

operation01空气侵入变压器内（检查油系统严密性）Airintrudesintothe

transformer(checkthetightnessofthe

oilsystem)02渗漏油或其它原因使油位降低Oilleakageorother

reasonslowertheoil

level03瓦斯继电器本身故障Theself-failureofgas

relay04二次回路故障引起瓦斯误发信号Secondarycircuit

failurecausesfalsegas

signal轻瓦斯发信后的处理TreatmentofLightGasafterLetter

Delivery瓦斯继电器动作后，要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。Afterthegasrelayoperates,thegasaccumulatedinthegasrelayshouldbecollectedimmediately,andfurtherjudgmentshouldbemadebyidentifyingthepropertyofthe

gas.瓦斯气体的收集采用注射器法，同时取两支样品，一支作点燃试验，另一支作色谱分折，不得在瓦斯继电器放气阀门处直接做点燃试验。Usethesyringemethodtocollectgas.Taketwosamplesatthesametime,oneforignitiontestandtheotherforchromat