电气专业毕业设计英文文献.docx

电气专业毕业设计英文文献.docx

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电气专业毕业设计英文文献

外文资料与中文翻译

外文资料：

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,canselectdifferentmoduleforusetodifferentprotectionwanton