外文翻译--变频器和单片机的基本知识.doc -- 5 元

BasicKnowledgeofInvertersandSinglechipFrequencyACmotorspeedcontrolusedastheprincipalmeanshavebeenusedinawiderangeofapplicationsintheindustrialarea.Ithasawiderangeofspeed,steadyspeedandhighprecision,fastdynamicresponseforawiderangeoftechnicalperformanceandreliableoperationhasbeengraduallyreplacetheDCmotorspeedcontrolsystem.Therearethreemaincontroltypesofinverterfirst,throughtheoperatorpanelinverter,thatis,throughtheoperationpaneltochangetheoutputfrequencyandotheroperatingparameters.Second,inthefrequencyconverteranaloginput010Vor420mAsignal.Controltheoutputfrequencybychangingthesizeofinputanalogconverter.Third,controlthecommunicationsportthroughtheinverter.Thefirstsceneingeneralisusedformanualadjustmentandparametersettings,Thelattertwokindsofmethodsaremostlyusedforautomaticregulationandremotecontrol.CommonlyPLC,DCSandothercontrolsystemsinindustrialareaareapplicabletotheconditionsofinverterinterfacecontrolmodule,whichcanfacilitatetherealizationoftheclosedloopconverterautomaticcontrol.Theyaremorecommonlyusedinlargeandmediumsizedcontrolsystems.Forsomesmallexperimentaldeviceandembeddedcontroldevice,besidescontrollingthefrequencyconverter,theprocessorgenerallyalsoneedtodealwithkeyboardinput,display,dataacquisitionandotherworksuchasprocesscontrol.Suchcontrolismoresuitableforsinglechipcontrolsystemasthecore.WhenitcomestothePLCintheformofadditionaloperatingpanel.Itcanachievethefunctionbutthecostistoohigh,Soitshouldnotbeused.Usingsinglechipcontrolinvertercanchoosethelasttwokindsofmethods.Theadvantageoftheuseofcommunicationcontrolfullcontrolfunction.Bytheappropriatelevelshiftinginvertercircuitsuitablefortheformofcommunication,thenitcancommunicatewiththeinverter.Thehardwareissimple.Theconnectionbetweenthemfacilitateasmallnumberofconnections.Thedisadvantageistheneedtounderstandthecommunicationprotocolconverterinordertocontroltheprogramming,andthesoftwaredesigniscomplex.Asinverterfordifferentbrandsofcommunicationinterfacesandcommunicationprotocolsaredifferent,thereisnouniformstandardcanonlybedevelopedforafrequencyconverter,whichreducesthechoicevarietiesoffrequencyconverter,andtheapplicabilityislimited.Asfortheanaloginputcontrol,thenalmostalloftheinvertercansupport.Althoughinmoresinglefunction,itcanachievethemainfunctionsofthevariesspeed.Anditcanmeettheuserequirementsofthemajorityofoccasions,soitisuniversal.Themostcommonlyusedmethodofanaloginputspeedisthroughpotentiometertoadjustthefrequency.Thatis,tochangetheanaloginputvoltagevaluetoachievethepurposeofspeedregulation.Althoughtheuseofamechanicalpotentiometerissimple,buteasytowearandhasnoenoughlongtermstability.Besidesthereisoneofthegreatestshortcomingsisthatitisonlysuitableformanualadjustment.Automaticadjustmentcannotbeachieved.DigitalPotentiometersusedtoreplacemechanicalpotentiometersinsinglechipcontrolnotonlyachievesimpleVVVFmanually,butalsoinaccordancewithPIDclosedloopcontroltoachieveautomaticcontrol.Itcanberegardedasagoodwayofafullfeaturedsinglechiptocontroltheinverter.SinglechipcomponentsInadditiontooperation,singlechipalsoneedcompletecontrol.Therefore,countingandtimingcannotbeseparated.Asaresult,singlechipissettedwiththecounterandtimersettings.Sofarhere,wealreadyknowthebasiccomponentsofsinglechip,thatis,singlechipissettedbytheCPU,readonlymemory,readwritememory,input/outputcomponentsandsoon.Infactthereisalsoasinglechipclockcircuit,whichduringtheoperationandcontrolofsinglechipcanbecarriedoutrhythmically.Inaddition,therearethesocalledinterruptsystemjanitorsroom.Whenthesinglechipmicrocomputertocontroltheparametersoftheobjectneedtoreachacertainstatetointervene,thenthejanitorsroomcanbecommunicatedtotheCPU.SothatCPUinaccordancewiththeprioritiesofexternalaffairstotakeappropriatecountermeasures.SinglechipinstructionsetandassemblylanguageprogramSinglechipmicrocomputerhasbeendescribedinfrontofthemaincomponent,thesepartsconstitutesinglechiphardware.Thesocalledhardware,istosee,canbetouchedandreceived.However,havingsuchahardwareonlymeanshavingthepossibilityoftherealizationofthecalculationandcontrol.Trulysinglechipmicrocomputertocalculateandcontrolcanalsobecoordinationofsoftware.Softwarereferstovariousprocedures.Onlythecorrectprocedurewouldbedepositedinavarietyofsinglechip,itcanworkeffectively.Therefore,singlechipmicrocomputercanautomaticallycomputingandcontrol,itispreciselybecausepeoplecontroltherealizationofthecalculationstepswithastepbysteporderform,thatisdepositedinapreinstructionstothememory.IntheCPUscontrol,thesinglechipwillbeacommandtocheckout,andthetranslationandimplementation.Allofthesetakeanumber,sendafew,thesumofdeposit,etc.areafewoperations.Wehaveimplementedrequiresacomputertooperatewithavarietyofformstowritedowntheorder,whichisinstruction.ButhowcanweidentifythemandtoperformtheseoperationsThisisasinglechipinthedesignbythedesignersoftheinstructiongiventoitbydecision.Acommandcorrespondstoabasicoperation.Allthecommandsthatsinglechipcanimplementisthesinglechipsystems.differenttypesofsinglechiphavedifferentcommandsystems.Whenusethesinglechip,thepriorthatshouldbetheproblemtobesolvedisaseriesofcommands.Theseinstructionsmustbeselectedtoidentifyandimplementsinglechipinstructions.Singlechipcustomerstosolvetheirownproblemsbytheinstructions,knownasthesource,fortheprocedure.Opcodeinstructionsareusuallydividedintotwomajorparts,whichareoperationofthecomputerandoperand.Operationofthecomputercodemeanstheimplementationofanyoperation,thatis,thefunctionofcommand.Operandmeansparticipateintheoperationoroperandaddressislocated.Becausesinglechipisaprogrammabledevices,whichrecognizeonlythebinarycode.Inorderoperationsinglechip,singlechipmicrocomputersysteminalldirectionsmustbeintheformofbinarycodetorepresent.MCS51singlechiphas8bitwordlength.Sometimes,itcannotfullycompleteacertainoperationusingonlyoneexpressedbytes.Therefore,thereisnotonlysinglebyteinstruction,butalsoanumberofbyteinstructionsintheinstruction.Byaseriesofbinary0and1components,thereisnoobviouscharacteristics,poormemory,difficulttounderstandandeasytomakemistakes.Therefore,thedirectuseofitisverydifficulttowriteprocedures.Thus,peopleusesomeMnemonic–usuallytheEnglishabbreviationofthecommandfunctiontoreplaceopcode.Inthisway,thereareclearinstructionsforeachactionfeatures,easytomemoryandunderstanding,andnotpronetoerror.Mnemonicusedtopreparetheprocessiscalledassemblylanguageprogram.However,Mnemonicpreparedtofacilitateunderstandingoftheprocesscanberecognizedonlysinglechipbinarymachinecode,so,inordertoallowsinglechipcanunderstandtheassemblylanguageprogrambereplacedbyaprocedureconsistingofbinarymachinecode.Thespeciesoftheconversionprocess,knownascompilation.Compiledcanbeachievedthroughmanuallookuptablemethod.WealsocandrawonPCmachinethroughthesocalledcrossassemblertocomplete.Posedbythebinaryprocess,oncetheuserhasenteredasinglechip,andthenstartthesinglechip,itcanentertheprocesstoimplementthemandate.TheCPUof8051singlechipismadeofthecontrollerandthecompositionoperator.CalculatorCalculatorcompletesthebinaryarithmetic/logicoperationsasthecorecomponents.Togetherwithregisters,accumulator,register,theprogrammarksthestateofprocessorregistersandBoolean.Accumulatorisamarkofeightregisters,whichisthemostfrequentlyworkingCPUregister.Inarithmeticandlogicoperations,theaccumulatorisoftentemporaryinaprecomputingoperands,andcomputingandthensavetheresults.Registerisprimarilyformultiplicationanddivisionoperations.Registerisalsoamarkofeightregisters,usedtostoresomeresultsofthecharacteristicsofcomputing,suchasbinary,bybit.ControllerControlleristhenervecenteroftheCPU,whichincludesthetimingcontrollogiccircuit,aninstructionregister,decoder,addresspointerandprogramcounter,stackpointerandsoon.Heretheprogramcounterisofamarkofsixteenregisters.Tomakethesinglechipoperateimplementationofaprogram,itisnecessarytoadvancetheprogramintoanareaofmemory.Singlechipactionshouldbetakenoutofasequenceofinstructionstobeimplemented.Therefore,theremustbeacircuittofindoutwherethecommandmoduleaddress,andthecircuitistheprogramcounter.Whenthesinglechipoperateimplementationofprocedures,putintotheprogramcounterwiththeinstructionofthefirsttheaddress.Whenittookoutacommandforeach,theprogramcounterautomaticallyincreasethecontentof1,andpointtothenextinstructionaddress.Sothattheimplementationofdirectivescanbeoperatedinorder.Onlywhenencounteredthetransferofcommandprocedures,subroutinecallinstructions,orfacefailure,theprogramcounterneedgotoplaces.8051CPUsdesignatedaddressfromthememorymoduleoutofthecorrespondinginstructionbytesofstorageontheinstructionregister.Then,theinstructionsininstructionregisterdecodercodehasbeentranslatedintovariousformsofcontrolsignals,thesesignalswiththesinglechipclockoscillatorgeneratedclockpulseinthetimingandcontrolcircuitincombinationtoformacertainperiodoftimebychangingthebeatlevelandtheclock,whichisthesocalledcontrolofinformation.ItintheInternalcoordinationofCPUdatatransfersbetweenregisters,anddoothercomputingoperations.