电气专业毕业设计英文文献整理版Word格式.docx
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Relayprotectionpresentsituationanddevelopment
一、Relayprotectiondevelopmentpresentsituation
Electricalpowersystem'
sswiftdevelopmenttotherelayprotectionproposedunceasinglythenewrequest,theelectronictechnology,thecomputertechnologyandcommunication'
sswiftdevelopmentunceasinglyhasinfusedthenewvigorfortherelayprotectiontechnology'
sdevelopment,therefore,therelayprotectiontechnologyisadvantageous,hascompletedthedevelopment4historicalstagein40remainingyearsoftime.
Afterthefoundingofthenation,ourcountryrelayprotectiondiscipline,therelayprotectiondesign,therelayfactoryindustryandtherelayprotectiontechnicalteamgrowsoutofnothing,haspassedthroughthepathwhichinabout10yeartheadvancedcountrieshalfcenturypassthrough.Inthe50s,ourcountryengineersandtechnicianscreativelyabsorption,thedigestion,havegraspedtheoverseasadvancedrelayprotectionequipmentperformanceandthemovementtechnology[1],completedonetohavethedeeprelayprotectiontheoryattainmentsandtherichserviceexperience'
srelayprotectiontechnicalteam,andgrewtheinstructionfunctiontothenationalrelayprotectiontechnicalteam'
sestablishment.TheAchengrelayfactoryintroductionhasdigestedatthattimetheoverseasadvancedrelaytechniqueofmanufacture,hasestablishedourcountryownrelaymanufacturingindustry.Thereforeourcountryhascompletedtherelayprotectionresearch,thedesign,themanufacture,themovementandtheteachingcompletesysteminthe60s.Thisisthemechanicalandelectrical-likerelayprotectionprosperoustime,wasourcountryrelayprotectiontechnologydevelopmenthaslaidthesolidfoundation.
Fromthelate50s,thetransistorrelayprotectionwasstartingtostudy.Inthe60stothe80sinisthetimewhichthetransistorrelayprotectionvigorousdevelopmentandwidelyuses.AndtheTianjinUniversityandtheNanjingElectricpowerAutomationPlantcooperationresearch'
s500kvtransistordirectionhighfrequencyprotectiondevelopswiththeNanjingElectricpowerAutomationResearchinstitutethetransistorhighfrequencyblocksystemisawayfromtheprotection,movesontheGezhouDam500kvlines[2],finishedthe500kvlineprotectiontodependuponcompletelyfromtheoverseasimporttime.
Fromthe70s,startedbasedontheintegrationoperationalamplifier'
sintegratedcircuitprotectiontostudy.Hasformedthecompleteseriestothelate80sintegratedcircuitprotection,substitutesforthetransistorprotectiongradually.Thedevelopmentwhich,theproduction,theapplicationprotectedtotheearly90sintegratedcircuitwerestillinthedominantposition,thiswastheintegratedcircuitprotectiontime.TheintegratedcircuitpowerfrequencychangequantitydirectionwhichdevelopsinthisaspectNanjingElectricpowerAutomationResearchinstitutehighfrequencyprotectedtheinfluentialrole[3],theTianjinUniversityandtheNanjingElectricpowerAutomationPlantcooperationdevelopment'
sintegratedcircuitphasevoltagecompensationtypedirectionhighfrequencyprotectionalsomovedinmany220kvandonthe500kvline.
Ourcountrynamelystartedthecomputerrelayprotectionresearchfromthelate70s[4],theinstitutionsofhigherlearningandthescientificresearchcourtyardinstituteforerunner'
sfunction.HuazhongUniversityofScienceandTechnology,theSoutheastUniversity,theNorthChinaelectricpowerinstitute,Xi'
anJiaotongUniversity,theTianjinUniversity,ShanghaiJiaotongUniversity,theChongqingUniversityandtheNanjingElectricpowerAutomationResearchinstituteoneafteranotherhasdevelopedthedifferentprinciple,thedifferentpatternmicrocomputerprotectivedevice.in1984theoriginalNorthChinaelectricpowerinstitutedevelopedthetransmissionlinemicrocomputerprotectivedevicefirstthroughtheappraisal,andobtainedtheapplicationinthesystem[5],hasopenedinourcountryrelayprotectionhistorythenewpage,protectedthepromotionforthemicrocomputertopavetheway.Inthemainequipmentprotectionaspect,thegeneratorwhichtheSoutheastUniversityandHuazhongUniversityofScienceandTechnologydevelopslosesmagnetismprotection,thegeneratorprotectionandthegenerator?
Bankoftransformersprotectionalsooneafteranotherin1989,in1994throughappraisal,investmentmovement.TheNanjingElectricpowerAutomationResearchinstitutedevelopsmicrocomputerlineprotectivedevicealsoin1991throughappraisal.TianjinUniversityandNanjingElectricpowerAutomationPlantcooperationdevelopmentmicrocomputerphasevoltagecompensationtypedirectionhighfrequencyprotection,Xi'
anJiaotongUniversityandXuchangrelayfactorycooperationdevelopmentpositivesequencebreakdowncomponentdirectionhighfrequencyprotectionalsooneafteranotherin1993,in1996throughappraisal.Hence,thedifferentprinciple,thedifferenttype'
smicrocomputerlineandthemainequipmentprotectunique,providedonegroupofnewgenerationperformancefortheelectricalpowersystemtobefine,thefunctionwascomplete,operationreliablerelayprotectioninstallment.Alongwiththemicrocomputerprotectivedevice'
sresearch,inmicrocomputeraspectsandsoonprotectionsoftware,algorithmhasalsomademanytheoryprogresses.Maysaythatstartedourcountryrelayprotectiontechnologyfromthe90stoenterthetimewhichthemicrocomputerprotected.
二、futuredevelopmentofRelayprotection
Thefuturetrendofrelayprotectiontechnologyistocomputerization,networkingisintelligent,protect,control,measureanddatacommunicationdevelopingbyintegration.Theprinciplesofprotectionofelectricpowercircuitsarequiteindependentoftherelaydesignswhichmaybeapplied.Forexample,ifthecurrenttoanelectriccircuitoramachineisgreaterthanthatwhichcanbetolerated,itisnecessarytotakeremedialaction.Thedeviceforrecognizingtheconditionandinitiatingcorrectivemeasureswouldbetermedasanover-currentrelayregardlessofthemechanistsbywhichthefunctionwouldbeaccomplished.Becausethefunctionsofelectromechanicaldevicesareeasilydescribed,theirperformancewillseverasabasisforpresentingadescriptionofrelaysandrelaysystemsingeneral.Relaysmusthavethefollowingcharacteristics:
Reliability---Thenatureoftheproblemisthattherelaymaybeidleforperiodsextendingintoyearsandthenberequiredtooperatewithfastresponds,asintended,thefirsttime.Thepenaltyforfailuretooperateproperlymayrunintomillionsofdollars.
Selectivity---Therelaymustnotrespondtoabnormal,butharmless,systemconditionssuchasswitchingtransientsorsuddenchangesinload.
Sensitivity---Therelaymustnotfailtooperate,eveninborderlinesituations,whenoperationwasplanned.
Speed---Therelayshouldmakethedecisiontoactasclosetoinstantaneouslyaspossible.Ifintentionaltimedelayisavailable,itshouldbepredictableandpreciselyadjustable.
Instantaneous---Thetermmeansnointentionaltimedelay.
Thereareseveralpossiblewaystoclassifyrelays:
byfunction,byconstruction,byapplication.Relaysareoneoftwobasictypesofconstruction:
electromagneticorsolid-state.Theelectromagnetictypereliesonthedevelopmentofelectromagneticforcesonmovablemembers,whichprovideswitchingactionbyphysicallyopeningorclosingsetsofcontacts.Thesolidstatevarietyprovidesswitchingactionwithnophysicalmotionbychangingthestateofseriallyconnectedsolidstatecomponentfromnoconductingtoconducting(orviceversa).Electromagneticrelaysareolderandmorewidelyused;
solidstaterelaysaremoreversatile,potentiallymorereliable,andfast.
1)Computerization
Withswiftandviolentdevelopmentofcomputerhardware,computerprotecthardwaredevelopconstantlyeven.Thepowersystemisimprovingtothedemandthatthecomputerprotectsconstantly,besidesbasicfunctionprotected,shouldwithtroubleinformationofthelargecapacityanddatathelong-termparkingspacealso,fastdataprocessingfunction,strongcommunicationcapacity,networkinordertosharethewholesystemdata,information,ability,networkofresourcewithotherprotection,controldevice,dispatcher,high-levellanguageprogramming,etc..Thisrequirescomputerprotectortohavefunctionwhichisequivalenttoapcmachine.Incomputerisitdevelopinitialstagetoprotect,isitmakewithoneminicomrelayprotectioninstalltoimagine.Becausethesmall-scaleorganismwasaccumulatedgreatly,withhighcostsatthattime,dependabilitywasbad,thisimagineditwasunrealistic.Now,exceedtheminicomputerofthoseyearsgreatlywithcomputerprotectorsizesimilarworkerfunction,speed,memorycapacityofaccusingofmachine,somakewithcompletesetsofworkerpersonwhoaccuseofopportunityofrelayprotectionalreadyripe,thiswillbeoneofthedevelopingdirectionthatacomputerisprotected.Tianjinuniversityisitspendwhomtransformationactascontinuetheelectricprotectorwithcomputerprotectorstructureself-sameoneworkerpersonwhoaccuseoftodevelopintoalready.Theadvantageofthiskindofdeviceisasfollows,
(1)ithavefunctionsof486pc,itcanmeettoatpresentanditisvariouskindsoffunctiondemandwherecomputerprotectfuture.
(2)Thesizeandstructurearesimilartopresentcomputerprotector,thecraftissuperior,takesprecautionsagainstearthquakes,defendsoverheatedlyanddefendingtheelectromagneticabilityofinterferingstrongly,canoperateitinveryabominableworkingenvironment,thecostisacceptable.(3)Adoptingstdbusorpcbus,hardwaremodule,canselectdifferentmoduleforusetodifferentprotectionwan