外文翻译--基于68HC908MR16单片机的光伏正弦波逆变电源.doc

PhotovoltaicPowerPupplyPinePaveInverterBasedOn68HC908MR16MCUIntroductionWiththegrowingenergycrisisandincreasetheenvironmentalawarenessofmankind,thedevelopmentandutilizationofnewenergyisreceivingincreasingattention.Andsolarenergyasaninexhaustiblesupplyofhighlyefficientnon-pollutingenergyhasmorepeopleofallages.Inthispaper,thephotovoltaicpowersystemissinusoidalinvertersuitableforahousehold,especiallyforelectricitywithoutelectricityinremoteareasofthewesternregionofapowersystemusers,asChinaswesterndevelopmentwillbeitsmarketprospectswillbecomemoreandmorebroad.2Structureandprincipleoftheinvertersystem2.1ThebasicstructureofthesystemFirstofall,bythesolararraytothebatterychargingcircuitinordertogetabasicstabilityoftheDCvoltage,andthenbytheinvertercircuitwillbehigh-frequencyalternatingcurrentintodirectcurrentreverse,andfinallybythefrequencystep-uptransformerandfiltercircuitfilteringinto50Hz,220VsinusoidalACvoltage.Controlofthewholesystemiscompletedbyasingle-chipMR16.ThecorepartoftheformationofSPWMwaveandtheoutputACvoltageaccordingtothefeedbackform,composedofsamplingdigitalPIregulatorpart.2.2Single-chipontheMR1668HC908MR16singlechipisalow-cost,high-performancesingle-chip8.Ithas32kbytesofrewritableflashmemory-chipFLASH,with768bytesofRAM,thissystemcompletelyenough；withadedicatedmotorcontrolfor6-channelPWMoutputPWMMCmodules,suitableforinsingle-phase,three-phaseinverter,atthesametimethemodulewasalsodevotedtotheprotectionFaultFAULTpin4,whenthefaultdoesnotoccurinthecaseofinterruptioncausedbytherapidblockadeofthePWMoutputtoachievethepurposeofprotection；withtheoptionexternalcrystalclockorinternalclockphase-lockedloopclockgeneratormodule,thesystemchosenbytheinternalPLLclockcanproduceaccurate8MHzinternalbusfrequency,soastoensuretheaccuracyofthefrequencyofthesystem；withprogrammableADclock,ADfastestconversiontimeonly2s,tominimizedisruptionofprogramexecutiontime；withSCIserialcommunicationinterface,canworkinfull-duplexorhalf-duplexmode,inthissystemcanreliablybecompletedwiththeoutsideworldkeyboardmonitorserialcommunicationsystem.2.3InverterMainCircuitSwitchingdeviceisappropriateforlow-powerdevices,withswitchingspeed,highfrequencycharacteristicsofthepowerMOSFET.Switchgatedrivesignalfromthesingle-chipMR16wavegeneratedbytheSPWMsignaldrivercircuit.Full-bridgeinverterSPWMoutputforhigh-frequencywave,thestep-uptransformerandfilterimmediatelybe220V,50HzstandardACvoltagesinusoidal.2.4SPWMwaveformation68HC908MR16withaspecialsingle-chipmotorcontrolcanbeusedtoworkinthreepairsofcomplementarymodeorstandalonemode,including6-channelPWMoutputmodulePWMMC.InitializationofthesysteminitsworkinthreepairsofcomplementarypatternsinthesamebridgethatthetwoPWMsignalarmiscomplementary,intheinitializationofdollarstowriteavaluetothePMOD(H:L)inordertodeterminethecarrierfrequencythatisswitchingfrequency.Real-timewavePWMpulsewidthcalculationiscompletedbytheinterruptionoftheprocedure,eachPWMMCmodulePCTN(H:L)countercountstoPMOD(H:L)ofthevalueofinterruptioncaused.Pre-0360°tothesinevaluesstoredinFLASHintoforminagivenregion,eachfailuretotakeasinevalue,aftersomecalculations,Ihaveavalue,besenttoPVALX(H:L)register,single-chipwillPVALX(H:L)ofthevalueofPMOD(H:L)afterthevalueintheautomaticgenerationofSPWMsignalsentbythePWMpin.InordertopreventthesamebridgearmofthetwotubesatthesametimethephenomenonofconductionoccurredintheabsenceofsignalgeneratorDEADTIMEinDEADTMwritesaregistervaluetodeterminethedeadtime.Thedesignofthesystemdeadtimefor2.5s,thecarrierfrequencyto10kHz,including200madetoenlargethevalueofthesinesinetable.Thereare4modulesPWMMCfaultprotectionportFAULT1FAULT4,whentheportwhenhigh,PWMMCinitializationcanbesettoblockinaccordancewiththecorrespondingPWMoutput,thesystemistheuseoftheover-currentprotectionfunction,Whenover-current,itFAULT1homeportinordertoplaceallsixroadblockadePWMport.PWMMCworkthesystemsothatthecenteralignmentmode,inthePWMclockfrequencyof8MHzcarrierunderitsformulaforthecycleCarriercycle=1/10k=PMOD(H:L)×(1/8M)×2Therefore,thesystemmustbeinitializedPMOD(H:L)=$0190(Note:$fortheMR16inhexadecimalnotation)2.5SystemcontrolstructureThesystemthroughthedigitalPIregulatortocontroltherealizationofregulators.Thecontrolsystemblockdiagramshowninfigure3.ACvoltagefeedbacksignalfromtheADsample,inordertoensureaccuracy,thesystemusessamplingvoltagetransformer.Juststarttosetoutputvoltagefromthesoft-start,soft-startisgeneratedatstartupinordertoavoidlargepeakcurrent,soft-starttheuseofsuccessiveincrementalincreasestoavoltagerequiredforthemethod,afterthesoft-startvoltageissettocorrespondto220Vvoltagevalues.Inordertoenhancethespeed,thesystemusesafeedforwardcontrolandfeedbackcontrolofthecontrolmethodofcombining.Inordertoenhancetheoutputcharacteristicsofthedynamicsystem,thesystemchangesinaccordancewiththeratioofdeviationofthesizeofcoefficientandintegralcoefficientofthefuzzycontrolmethod,whenthedeviationislarger,theproportioncoefficientandintegralcoefficientisalsolarger,whenthedeviationoftheproportionofsmallcoefficientsandintegralcoefficientsmaller,thusreducingtheovershoot,itiseasytomakethesystemstable,thetotaleliminationoftheintegralsaturationphenomenon,butalsotoenhancetheadaptabilityofthesystem.3SerialCommunicationInordertoenhancethesystemsabilitytoadapttodifferentenvironments,itisnecessarytomonitorandcontrolsystemtomonitorandmodifytheparametersofregulation,thissystemusesaserialcommunicationtechnologykeyboardmonitoringsystemwiththeoutsideworldtocommunicate.Proceduresontheuseofinquirymethodstotheoutsideworldperiodicallysendtestdata,testdataincludingthesolarcellvoltage,chargecurrent,batteryvoltage,DCcurrent,outputvoltage,outputcurrent,heatsinktemperature,whentheeventofthefailureprioritysendfaultsignal,whentheneedtomodifyparametersandmodifydataonthereceptionofthecorrespondingparameters,andusethemethodsofcalibrationandcalibrationtestoftheaccuracyofdatacommunications.MAXIMshardwareasaMAX485interfacechiptoworkinhalf-duplexmode,whilethesystemoptocouplerisolationsystemsapproachtoenhanceanti-interferenceabilityandreliability.4SystemsoftwaredesignThemodulardesignofsystemsoftware,includingtheinitializationmodule,theprotectionmodule,regulatormodules,communicationmodules,suchasinterruptionofprogrammodules,inadditiontodisruptionofmodulesoutsidethemainprogramontheremainingmodules,whichwillCompletionofsysteminitializationmainmoduleinitialization,thevariableunit,giventheinitialvalueoftheregisterunit.ProtectionmoduleinaccordancewithvoltageandcurrentsamplevaluestodeterminefaultandthefaultoccursinthePWMoutputoftheblockade.Protection,includingunder-voltagebattery,batteryover-voltage,systemoverload,overheatingprotection,includingbatteryvoltage,over-voltageprotectioncanbeachievedsincetherestoration,thatis,thebatteryvoltageisdetectedandreturnedtonormal,thesystemre-soft-startandresumenormalwork.Overcurrentprotectionasaresultoftherapidresponsetheyneedtoprotecttheuseofhardware,whentheover-currentatthetimeoftheblockadeassoonasallthePWMoutput,butalsosealedoffallthedrivingcircuit,onlytoreturntoworkcanbereset,softwarecandeterminewhethertherehasbeenover-currentprotection.RegulatormoduletocompletethesystemofthePIregulatoroutputvoltageregulation,sothattheoutputvoltagestabilizedat220V,whilesoft-startonthemalso.Theentrancetotheoutputparametersforthesoft-startexportstothedisruptionmoduleMparametersinvolvedinthecalculationofPWMpulsewidth.Throughreal-timeadjustmentofthevalueoftheparametervaluecanbechangedsothattheoutputpulsewidthgiventofollow.InterruptionofprogrammodulestocompletetheissueofSPWMwaveform,ACvoltage,ACcurrentparametersofthesample.InterruptionoftheentranceparametersofPIregulatorfortheoutputparameterM,theparametersinvolvedinthecalculationofpulsewidththatisPVALX(H:L)valuescalculated,thuschangingthedutycyclewhichregulatestheoutputvoltage.2inaccordancewiththerulesofSPWMsamplingmethods,combinedwiththeinitializationofPWMMCsetformulaforcalculatingreal-timepulsewidthforIsahalfcycle:PVALX(H:L)=PMOD(H:L)/2+M×SIN(PTR)Negativehalf-cycle:PVALX(H:L)=PMOD(H:L)/2-M×SIN(PTR)OnePTRpointertosinetable,SIN(PTR)forthecorrespondingsinevalueofthepointerPTR.Prototypemadeinaccordancewiththeabovethinking,thelasttoberelativelystandard220V,50Hzsinusoidalvoltage,soft-startisalsoverystable,itsfrequencyerror0.1%,theoutputvoltageerrorof0.5%.Asaresultofthecarrierfrequencyof10kHz,inthetransformerprimarysidetobe20kHzhigh-frequencysignalswithoutnoise.Undertheabove-mentionedcontrolcanensurethesystemloadorasuddenreductioninloadtomaintainoutputvoltagestabilityquickly.Keyboardandmonitorsystemwiththeoutsideworldoftheserialcommunicationgood,strongpracticalityandreliability.