电力英文翻译.docx
- 文档编号:10430581
- 上传时间:2023-02-11
- 格式:DOCX
- 页数:9
- 大小:23.46KB
电力英文翻译.docx
《电力英文翻译.docx》由会员分享,可在线阅读,更多相关《电力英文翻译.docx(9页珍藏版)》请在冰豆网上搜索。
电力英文翻译
PowerTechnologyandEngineeringVol.38,No.5,2004
ENERGYSYSTEMSANDELECTRICALNETWORKS
TECHNICALSTATEOFBASICEQUIPMENT
OFSUBSTATIONSANDOVERHEADTRANSMISSIONLINES
ANDMEASURESFORRAISINGTHEIRRELIABILITY
D.S.Savvaitov1andL.V.Timashova1
TranslatedfromÉlektricheskieStantsii,No.8,August2004
Abriefdescriptionofthestateofbasicequipmentemployedin110–750-kVpowernetworksispresented.Problemsarisinginoperationofthisequipmentareoutlinedandrecommendationsonimprovingitsreliabilityaremade.Transformerequipment,high-voltagecircuitbreakers,disconnectors,measuringtransformers,nonlinearovervoltagesuppressors,andtransmissionlinesareconsidered.
Keywords:
transformerequipment,high-voltagecircuitbreakers,disconnectors,measuringtransformers,overvoltagesuppressors,transmissionlines,servicelife.
Theexisting110–750-kVpowernetworkshavebeencreatedintheSovietUnionandarenowexperiencingthefollowingproblems:
—alargevolumeoftime-wornelectricequipmentatsubstations;
—poorcontrollabilityofthenetworkandinadequatevolumeofdevicesforvoltagecontrol;
—lowdesignreliabilityoftheactivetransmissionlines;
—outdateddesignofoverheadlines;
—useofsomeoutdatedtechnologiesandkindsofnetworkequipmentandcontrolsystems;
—lowlevelofautomationofnetworkobjectsandabsenceoffullyautomatedsubstations;
—inadequateperformancespecificationandmaintenanceofnetworkfacilities;
—highoperatingcosts.
Agreatpartoftheinstalledequipmenthasexhaustedstandardizedminimumservicelife.Itshouldbenotedthatdifferentkindsofequipmenthavedifferentload-lives.Ontheaverage,thesubstationequipmenthasbeenwornoutbyabout40%.RequirementsonreliabilityofthebasefacilitiesarestandardizedonlyinGOST687–78foraccircuitbreakersratedforover1000V.TheGOST687–78StateStandardalsoincludesrequirementsonthemechanicallifeevaluatedintermsofparameterNspecifiedforeverykindofcircuitbreaker.ForoverheadtransmissionlinesNisusuallyequalto1000on-offcycles.However,intheactualpracticeoverheadcircuitbreakersratedfor330–500kVfailafter240–380cycles.Wecanseethatthereliabilityofthebasepowerequipmentcanbeevaluatedonlywiththehelpofoperationaldata.Russiantransmissionlinesarechieflyequippedwithaircircuitbreakers.SF6circuitbreakersconstituteonly4%ofthetotalnumberofemployedbreakers.Theefficiencyofoperationofthesefourpercentcannotbeanalyzedatpresentduetotheabsenceofenoughdataintheirfailures.Thereliabilityofnonlinearovervoltagesuppressors(OVS)fabricatedbyvariousdomesticproducersisdeclaredinperformancespecifications,wheretheirservicelifeislimitedto25(or30)yearswithaprobabilityof0.98.Thismeansthat0.8(or0.67)outof1000OVScanfaileveryyear.Thesedeclareddatahavenotbeenconfirmedyetbyoperationalexperience.
Transformerequipment.
Transformers,autotransformers(AT),andshuntingreactorsarereliablefacilitiesatsubstations.TherelativelyhighlevelofqualityoflargetransformershasbeenensuredintheUSSRbystrictspecializationofproducers.AlllargetransformershavebeenproducedbytheZaporozh’yeTransformerPlant(ZTZ).TransformersfortheRussianpowerindustryareproducedbytheMoscowElectricPlant(MÉZ).OperationalexperienceshowsthatpowertransformersproducedintheUSSRandintheRussianFederationhavereliabilitycomparabletothelevelofforeignproducers.However,themassandsizeparametersspecifiedbyGOST12965–85andGOST17544–85(USSR)andthelosses,especiallytheno-loadones,arelowerthanintheworldpractice.Atthepresenttime,thefleetofpowertransformersratedto110–750kVamountstoabout30,000pieceswithatotalpowerof570GV⎽Aincludingabout25,000piecesratedto120MV⎽A.
About30%ofthetransformerequipmenthaveservedforover25years,andin2005abouthalfofthetransformerswillserveformorethat25years.Withoutallowanceforthedamageofterminals,harddamageoftransformersproducedpriorto1970amountsto1%;fortransformersproducedlateritamountstoabout0.2%.Ananalysismadeinthelastfiveyearsshowsthatthespecificannualdamageabilityoftransformersis0.45%.Thiskindofdamageisforthemostpartsevereandisaccompaniedbyexplosionandfireduetosparkoverthroughyellowscurfontheinternalsurfaceofthebottomcoverofbushings.About23.5%offailuresoccurwithloadtapchangedevices(LTC).IntheworldpracticeautotransformersalsofailfrequentlyduetothedamageofbushingsandLTC.5.36%failuresoccurduetoinappropriatestabilityofwindingsduringfaults,whichisthemostfrequentfor330-and500-kVautotransformers.Everyyearone-twofailuresoccurduetodefectsofmajorinsulation(includingburrsonwindingwires).
Modernautotransformershaveanefficiencyexceeding99.5%(in500-and750-kVATtheefficiencyexceeds99.7%)andverylowdamageability.Thefollowingmeasuresaretakeninordertoraisethereliabilityoftransformerequipment:
—useofmorereliablebushings,bushingswithsolidinsulationproducedbytheKhotkovoPlantincooperationwiththeABBCompany,bushingsproducedbythe“Izolyator”Plant,andimportedMicafilbushings,nowusedseldombecauseofthehighcost;—useofmorereliableLTC.TraditionalsupplierofLTCistheMaschinenfabrikReinhausenCompany(Germany).LessreliablebutcheaperdevicesareproducedbytheZaporozh’yeTransformerPlant;—useofdevicesformeasuringtheoiltemperaturefordeterminingtheheatloadontheATwithautomaticcontrolofcoolingdevicesinsteadofthenowusedpressure-filledthermometersthatgiveanerrorexceeding10°C;—useofforeignpracticeofmeasuringthetemperatureofwindings.Thismakesitpossibletocontroloverloadsifnecessaryandalsoindirectlycontrolthethermalwearoftheinsulation(ZTZandMÉZequipdomesticautotransformersandimportedtransformerswithsuchdevices).
High-voltage110–750-kVcircuitbreakers.
Thenational(all-Russian)powernetworkemploysover30,000circuitbreakersratedforfrom110to750kVofwhich80.5%are110-kVbreakers,15.2%are220-kVbreakers,1.2%are330-kVbreakers,3%are500-kVbreakers,and0.1%are750-kVbreakers.Over50%oftheinstalledcircuitbreakersaretank-typeoilswitchesratedforthevoltageof110and220kV(58%areratedfor110kVand45%areratedfor220kV).
Fromthe1930stothe1980stank-typeoilswitches(MKPandU)havebeenproducedbytheUralélektroapparatPlantandthenbytheUralélektrotyazhmashProductionAssociation.Live-tankcircuitbreakersfor110and220kVconstitute24.3%ofthetotalnumberofinstalledbreakers(27%110-Kvand17%220-kV).TheseareVMT-110andVMT-220circuitbreakersproducedbyUralélektrotyazhmash(UÉTM),MMO-110Bulgariancircuitbreakers,andasmallnumbercircuitbreakersimportedfromASEAandotherforeigncompanies.VMT-110andVMT-220breakersarebeingproduceduntilnow.In2000theywereshippedinanamountof285pieces,in2001theywereshippedinanamountof320pieces.TherespectivenumbersofVMT-220breakersare15and30pieces.Theamountofaircircuitbreakersisequalto18.6%ofthetotalnumberofinstalledbreakers(12%110-kV,35%220-kV,and97%330-and500-kV).AirbreakersoftheVVN,VV,VVB,VVD,andVNVserieshavebeenproducedbytheÉlektroapparatandUralélektrotyazhmashPlants.
Until1996RussianpowersystemshadsingleSF6circuitbreakersinpilotoperation.In1997itwasdecidedtoequipnewlyerectedandreconditioned330-and750-kVsubstationsoftheRAO“EÉSRossii”Co.withSF6circuitbreakers.Thenumberofsuchbreakersincreasedprogressivelyandnowamountsto4%.SF6column-typeandtank-typecircuitbreakersaresuppliedbyUÉTM(primarily110-kVbreakerswithbreakingcurrentofupto40kA),bythePowerMechanicalPlant(110-and220-kVtank-typebreakers),andbyforeignproducers(ABB,Alstom,Siemens).Aconsiderablepartoftheoilandaircircuitbreakersoperatingintheunitednational(all-Russian)electricnetworkareratedfor110and220kVandhaveexhaustedthespecifiedservicelife.Thisis35%ofthetotalnumberofbreakersinoperation.NinetypercentoftheMKP-110andVVN-110breakers,40%oftheU-110breakers,and50%oftheVVN-220breakershaveexhaustedtheirspecifiedservicelife.Thedamageabilityofcircuitbreakersisdeterminedintermsofthefailureflowcalculatedastheratioofthetotalnumberofallkindsoffailuretothetotalservicelifeofthebreakerscountedinbreaker-years.Fordomestichigh-voltagecircuitbreakersoftheVVseriesratedfor110–220kVthefailureflowparameteris0.07–0.08peryear;forthe500–750-kVswitchesitis0.13–0.15peryear.AccordingtothedataofCIGREthemeanfailureflowfor110-kVandhigher-voltagebreakersis0.01peryear.
Theworstreliabilityisreportedforthefollowingkindsofcircuitbreakers:
0.100peryearforMMO-110(Bulgaria),0.111peryearforVVB-110,0.134peryearforVVN-220,0.129peryearforVVN-330,0.242peryearforVVBK-500,and0.065peryearforVV(M)-500.Theseswitchesdonotmeettherequirementsofmodernstandards,includingtheparametersofreliability,switchingandmechanicallives,repairvolume,mass,andsize.Domesticcircuitbreakersareknowntobedamagedforthefollowingreasons:
—designdrawbacks;
—defectsduetolowqualityofmaterials;
—productiondefects;
—performanceandmaintenancefailures;
—presenceofshuntingreactorsandcapacitorbanksincircuitsforwhichthebreakersareunsuitable;
—operationunderconditionsofshort-circuitcurrents
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 电力 英文翻译