电气工程及其自动化本科毕业设计论文外文资料.docx

电气工程及其自动化本科毕业设计论文外文资料.docx

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电气工程及其自动化本科毕业设计论文外文资料

Unattendedsubstationandsubstationautomation

Thedevelopmentofautomaticreclosingmadetheunattendedsubstationpractical.Automaticoperation,withoutthecontinuouspresenceofanattendant（operator）,wasfirsttriedonthesynchronousconvertersubstationssupplyinganinterurbanelectricrailwayin1914.Intheearly1920s,thedevelopmentofautomaticreclosing,protectiverelays,andmeansforautomaticcontrolofvoltagemadeitpossibleforacsubstationstobecompletelyautomatic.Duringtheperiodwhenthesubstationshadtobecontrolledmanually,itwasnecessarythattheyhandleenoughpowertojustifytheoperator`swages.Thisdictatedlargestations,frequentlyservinglargeareasbymeansofmanyfeeders.Thefeedersthatservedthemoredistantpartsofanareahadtogoalongwaybeforetheypickedupanyload.Furthermore,astheloadonalargesubstationgrows,transformercapacityhastobeadded.Thisincreasestheshort-circuitcurrentonthesecondarysidesometimestheshort-circuitcapacityexceedstheinterruptingcapacityofthecircuitbreakersalreadyinstalled.Appropriateremediesincludebussectionalizing,theinstallationofreactorsorsomecombinationofthetwo.Suchmeasuresarefrequentlyexpensiveandinconvenientandtheyconstituteanundesirablelimitationonoperatingflexibility.

Oncetheunattendedsubstationbecameareality,thesubstationcouldbemadesmaller.Locatednearertheload,andlongfeederswerenolongernecessary.Thisnewmethodofdistributionhadbecomeavailablesinceloadgrowthcouldnowbeaccommodatedbyinstallinganothersubstationthatcouldcarrypartsofthearealoadsformerlycarriedbyadjacentsubstations.Usually,thereisnointerconnectionbetweenthecircuitsenergizedbythevarioussubstations.Consequently,thereisnoincreaseinshort-circuitseverity.however,atthedistributionlevel,tieswitchesareusedtoswitchfeedersorfeedersectionsbetweentransformersinthesamestationortoadjacentsubstationsforsubstationtransformerloadmanagement.

Automaticcontrolhasbeenappliedtolargerandlargersubstations,andtomanyhydroelectricgeneratingstations.Itisalsousedonindividualcircuitsandequipmentinmanyattendedstations.Forexample,eveninmanystationswhereanoperatorisonduty,outgoingoverheadfeedersarecontrolledbyautomaticreclosingrelays.Undersomecircumstances,itmaybeimpracticaltomakeastationcompletelyautomatic.Thesecircumstancescouldexistbecauseoftechnical,economic,orsafetyconsiderations.Astationneednotbeattendedeventhoughitisnotfullyautomatic,itispossibletocontrolastationfromanotherlocation,suchasalargerattendedstationorthesystemoperatingoffice.Thiscanbedonebymeansofsupervisorycontrol（aformofremotecontrol）.

BymeansofaSCADAsystem,anoperatoratadispatchcentercancauseoperationssuchastheopeningandclosingofbreakers,thestartingandstoppingofcondensers,andthechangingofthetapsontransformerswithloadtapchanger.Theoperatorcanreceiveanindicationthattheoperationhasbeencompleted.Allofthiscanbedoneoveravoice-gradecommunicationchannel.Itistheuseofvoice-grade,two-waycommunicationchannelsthatdistinguishessupervisorycontrolfromdirect-wireremotecontrol;Thelatterrequiresonedirect-wirecircuitforeachcontrolfromdirect-wireremotecontrol;Thelatterrequiresonedirect-wirecircuitforeachcontrolleddevice.SCADAequipmentsupplementsautomaticcontrol.Alloftheprotectiverelaysandmostofthecontrolrelaysrequiredforautomaticcontrolarealsonecessarywhensupervisorycontrolisused.Onlytheinitiatingdevicesmaybedifferentoromitted.Forexampleafullyautomaticsynchronouscondenserisstartedandstoppedbyaninitiatingdeviceresponsivetovoltageorcurrentorboth.Inaddition,therearemanyprotectiveandcontrolrelays.Ifthecondenseristobecontrolledbysupervisorycontrol,alltheotherdevicesarestillnecessary,andonlytheinitiatingdevicescanbeomitted.

Withtherecentrevolutioninmicroelectronicperformanceandcosts,digitalautomationsystemsarenowbeingdevelopedforpowersystems.Theseautomationsystemsprovideanintegratedsystemsconceptforprotection,control,andmonitoringfunctions.Theapproachutilizesdistributedmicroprocessor-basedmoduleslocatedwithinthesubstationsandortonthetransmissionanddistributionsystem.Thisprovidesprotectionandcontroldecisionsoutonthesystemwherethedataislocated.Byautomatictransmissionanddistributionsystems,majorbenefitswillbeobtained.Thereincludegreaterutilizationofexistingfacilities,reductionofcommunicationrequirements,deferralofmajorsysteminvestments,optimizedoperationsandmaintenance,improvedsystemreliability,moreefficient-systemoperationthroughlowerlossesandrapidrestorationofserviceafterafaultthefunctionsimplementedbyusingthisintegratedsystemsapproachinclude:

Transmissionautomationfunctionsanddistributionsubstationandfeederautomationfunctions.

Thetransformersubstationautomationandunmannedondutyarethepopulartopicsthatthechargedbarbedwirenetadjustsonedegreeautomationrealmnowadays,itsdevelopmentpowerheadisjustontheup.Theabroadhasakindofstandpointtothink,thepersonissubjectedtoenvironment,motion,personality,disease...etc.manyfactorinfluenceeasily,sooneselfbeanotdependablefactor.Reallytherearen'tafewtroublestobeingcausebytheartificialmistakeoperationof,seeingfromthisangle,nomantheondutyreallycanraisetocirculatecredibility.ForexampleZHENG4ZHOUDI4adjustasearlyas1959tostartadopttheremotecontroltechnique,morethan30inthelastyearsesesnevertakeplaceamistakeoperation;AgainifafterpowersupplybureauinShenzhencarryoutatransformersubstationnomanonduty,mistakeoperationthetroubleratelowered60%.

Thetransformersubstationautomationisatthecalculatortechniqueandthenetworkcorrespondencetechnicalfoundationupdevelop.Theabroadhasalreadyhadthedispersiontypetransformersubstationautomationtopublishin80's,takingSiemens（SIEMENS）companyasanexample,thatcompanythe1stwholedispersiontypetransformersubstationautomationLSA678asearlyas1985circulatesintheGermanHanoverdevotion,thetransformersubstationthatgotovariouselectricvoltagegradethat1993beginningofyearshavealreadyhadmorethan300systemsinGermanyandEuropecirculate.Thetransformersubstationautomationtheworkstartoftheourcountrytocomparewithnight,,aboutsince90's,thebeginningstartthestagemainlydevelopswithproduceaconcentrationtypeoftransformersubstationautomation,exampletypeDISA-1the［isone］,typeBJ-1the［is2］s,typesiES-60ses,AXWJK-1000types,etc.sFD-97.Startdevelopdispersionthetypetransformersubstationautomationinmid90's,suchasthetypesDISA-2s,typeDISA-3［3,4］s,BJ-F3s,typeCSC-2000the［is5］s,DCAP3200typeseses,FDKtypeetc.,comparedwiththeforeignadvancedlevelhaveamarginaboutfor10years.Manyhighschool,researchunits,themanufactoryhouseandprogrammingdesign,thesetingupwithcirculatesectionatstudyanddrawlessonsfromabroadforerunnertechnicalofinthemeantime,iscombinetheactualcircumstancejointeffortoftheourcountrytocontinuetodeveloptomatchmoreourcountrythetransformersubstationautomation［ofthestateofthenation3,4,6-12］s.Cananticipate,itwilldevelopmentandexpansionfromnowonofspeedwouldmoreandmorequick,withabroadofthemarginwillcontractgradually.

One,thetransformersubstationcategorize:

Transformersubstation'spresstheelectricvoltagegradecanisdividedintothehighpressure,extrahighvoltage,highpressureandmediumlowpressureespeciallyis4.Especiallyhighpressuretransformersubstation:

1000KV,750kVs;Extrahighvoltagetransformersubstation:

500KV,330kVs;Highpressuretransformersubstation:

220KV,110kVs,35kVs;Mediumlow-pressuretransformersubstation:

（calltogotogetherwiththeelectricitystationagain）10ThekVandfollowingelectricvoltagegrade.

Thetransformersubstationpressesinthepositioninthechargedbarbedwirenetcanisdividedintothevitalpointstation,theterminalstationwithtoturn3ofstand.Thevitalpointstand:

Inthechargedbarbedwirenetregardlessisthenet,astructurestillaburdenlevelsallareplacedinprominentposition;Theterminalstand:

Onlythehighpressureentersline,locatingthecircuitbitterendofthechargedbarbedwirenet;Wintoturnastation:

Thereare2roadhighpressurestoenterline,locatethecircuitmiddle.

Transformersubstation'spressthecontrolmethodcanisdividedintogathertocontrolastation（againcallabaseastation）andbecontroledastation.（callsonastationagain）Theformerisadjustedonedegreecentercontrol,andastoit'sthesurroundingssonstationtaketohavealreadyadjustedonedegreeoperationmission;Thelatterandtheterminalstationaresimilar,butbeplacedinthewreathformchargedbarbedwirenetprobablyin

Two,BEgathertocontrolthestationcontrol:

Thetransformersubstationpressestocirculatemodedemarcationtoturnondutyforsomeone:

Thisisthemostfamiliarmovementmodecurrently;Unmannedonduty:

Havenofixedmovementondutyapersonnel,reserveonlyindividualguardpersonnel,beresponsibleforstationinsideofsafesecurityworkandthetroubleabnormalitycircumstanceofurgentprocessing;Nomanvalueguard:

Nomanoftherealmeaningstation,atsomeflourishingwestnation,iftheUnitedStates,Canadianetc.ismorefamiliar.

Three,concentratetogotogetherwithtoho