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毕业设计（论文）外文文献翻译文献、资料中文题目：逆变器文献、资料英文题目：Inverter文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：班级：姓名：学号：指导教师：翻译日期：2017.02.14Inverter1IntroductionAninverterisanelectricaldevicethatconvertsdirectcurrent(DC)toalternatingcurrent(AC);theconvertedACcanbeatanyrequiredvoltageandfrequencywiththeuseofappropriatetransformers,switching,andcontrolcircuits.Solid-stateinvertershavenomovingpartsandareusedinawiderangeofapplications,fromsmallswitchingpowersuppliesincomputers,tolargeelectricutilityhigh-voltagedirectcurrentapplicationsthattransportbulkpower.InvertersarecommonlyusedtosupplyACpowerfromDCsourcessuchassolarpanelsorbatteries.Therearetwomaintypesofinverter.Theoutputofamodifiedsinewaveinverterissimilartoasquarewaveoutputexceptthattheoutputgoestozerovoltsforatimebeforeswitchingpositiveornegative.Itissimpleandlowcostandiscompatiblewithmostelectronicdevices,exceptforsensitiveorspecializedequipment,forexamplecertainlaserprinters.Apuresinewaveinverterproducesanearlyperfectsinewaveoutput(3%totalharmonicdistortion)thatisessentiallythesameasutility-suppliedgridpower.ThusitiscompatiblewithallACelectronicdevices.Thisisthetypeusedingrid-tieinverters.Itsdesignismorecomplex,andcosts5or10timesmoreperunitpowerTheelectricalinverterisahigh-powerelectronicoscillator.ItissonamedbecauseearlymechanicalACtoDCconvertersweremadetoworkinreverse,andthuswereinverted,toconvertDCtoAC.Theinverterperformstheoppositefunctionofarectifier.2Applications2.1DCpowersourceutilizationAninverterconvertstheDCelectricityfromsourcessuchasbatteries,solarpanels,orfuelcellstoACelectricity.Theelectricitycanbeatanyrequiredvoltage;inparticularitcanoperateACequipmentdesignedformainsoperation,orrectifiedtoproduceDCatanydesiredvoltageGridtieinverterscanfeedenergybackintothedistributionnetworkbecausetheyproducealternatingcurrentwiththesamewaveshapeandfrequencyassuppliedbythedistributionsystem.Theycanalsoswitchoffautomaticallyintheeventofablackout.Micro-invertersconvertdirectcurrentfromindividualsolarpanelsintoalternatingcurrentfortheelectricgrid.Theyaregridtiedesignsbydefault.2.2UninterruptiblepowersuppliesAnuninterruptiblepowersupply(UPS)usesbatteriesandaninvertertosupplyACpowerwhenmainpowerisnotavailable.Whenmainpowerisrestored,arectifiersuppliesDCpowertorechargethebatteries.2.3InductionheatingInvertersconvertlowfrequencymainACpowertoahigherfrequencyforuseininductionheating.Todothis,ACpowerisfirstrectifiedtoprovideDCpower.TheinverterthenchangestheDCpowertohighfrequencyACpower.2.4HVDCpowertransmissionWithHVDCpowertransmission,ACpowerisrectifiedandhighvoltageDCpoweristransmittedtoanotherlocation.Atthereceivinglocation,aninverterinastaticinverterplantconvertsthepowerbacktoAC.2.5Variable-frequencydrivesAvariable-frequencydrivecontrolstheoperatingspeedofanACmotorbycontrollingthefrequencyandvoltageofthepowersuppliedtothemotor.Aninverterprovidesthecontrolledpower.Inmostcases,thevariable-frequencydriveincludesarectifiersothatDCpowerfortheinvertercanbeprovidedfrommainACpower.Sinceaninverteristhekeycomponent,variable-frequencydrivesaresometimescalledinverterdrivesorjustinverters.2.6ElectricvehicledrivesAdjustablespeedmotorcontrolinvertersarecurrentlyusedtopowerthetractionmotorsinsomeelectricanddiesel-electricrailvehiclesaswellassomebatteryelectricvehiclesandhybridelectrichighwayvehiclessuchastheToyotaPriusandFiskerKarma.Variousimprovementsininvertertechnologyarebeingdevelopedspecificallyforelectricvehicleapplications.[2]Invehicleswithregenerativebraking,theinverteralsotakespowerfromthemotor(nowactingasagenerator)andstoresitinthebatteries.2.7ThegeneralcaseAtransformerallowsACpowertobeconvertedtoanydesiredvoltage,butatthesamefrequency.Inverters,plusrectifiersforDC,canbedesignedtoconvertfromanyvoltage,ACorDC,toanyothervoltage,alsoACorDC,atanydesiredfrequency.Theoutputpowercanneverexceedtheinputpower,butefficienciescanbehigh,withasmallproportionofthepowerdissipatedaswasteheat.3Circuitdescription3.1BasicdesignsInonesimpleinvertercircuit,DCpowerisconnectedtoatransformerthroughthecentretapoftheprimarywinding.AswitchisrapidlyswitchedbackandforthtoallowcurrenttoflowbacktotheDCsourcefollowingtwoalternatepathsthroughoneendoftheprimarywindingandthentheother.Thealternationofthedirectionofcurrentintheprimarywindingofthetransformerproducesalternatingcurrent(AC)inthesecondarycircuit.Theelectromechanicalversionoftheswitchingdeviceincludestwostationarycontactsandaspringsupportedmovingcontact.Thespringholdsthemovablecontactagainstoneofthestationarycontactsandanelectromagnetpullsthemovablecontacttotheoppositestationarycontact.Thecurrentintheelectromagnetisinterruptedbytheactionoftheswitchsothattheswitchcontinuallyswitchesrapidlybackandforth.Thistypeofelectromechanicalinverterswitch,calledavibratororbuzzer,wasonceusedinvacuumtubeautomobileradios.Asimilarmechanismhasbeenusedindoorbells,buzzersandtattooguns.Astheybecameavailablewithadequatepowerratings,transistorsandvariousothertypesofsemiconductorswitcheshavebeenincorporatedintoinvertercircuitdesigns3.2OutputwaveformsTheswitchinthesimpleinverterdescribedabove,whennotc