Frequency conversion power 變頻電源 英文文獻(xiàn)翻譯

PAGEPAGE7Frequencyconversionpower（變頻電源）FrequencyconversionpoweristheACutilitybyACandDCandACconversionforpuresinewave,output,theoutputvoltageandfrequencyadjustableinsidecertainlimits.Itisusedindifferentfrequencyconversionmotorspeedcontroller,differentfromthegeneralacvoltagestabilizer.Theidealacpowerischaracteristicoffrequencystability,voltagestabilityandresistanceequaltozero,thevoltagewaveformdistortionforpuresinewave.Frequencyconversionpowerisclosetoidealacpower,therefore,advanceddevelopedcountriesareincreasinglywillinverterpowersupplypower,soastoprovidethemostexcellentwithelectricpowersupplyenvironment,facilitateobjectiveappraisalappliancestechnicalperformance.Frequencyconversionpowermainlylargestcategories:linearputlargeandSPWMswitch.Structurally,frequencyconvertercanbedividedintodirectandindirectfrequency.Directlyintoafrequencyconverterandsaid,itisakindoffrequencyalternatingcurrenttodirecttheacfrequencyconversioncontrol,fornodclinkbetweenthefrequencyconversionandindirectform:ahasbeencalledintofrequencyinverter,willbepassedthroughrectifieractodcrectification,againthroughtheinverterfrequencyconvertingdcfrequencyformofvariablefrequency,thereforethiswayiscalledagainhavedclinkfrequency.Ageneraluseintoinverterswitchdeviceisthyristorusingautomaticvoltageiszeroandbecomenegativefeatures,thyristordirectlyontheacpower,thyristorcannaturallyshutoff.Theprocessandcontrolledrectifier,noneedforadditionalelementmethodissimple,reliableoperation.But,inalowfrequencyoutputwaveforminnearlysinusoidal,andforavariableflow,highefficiency,alsocanachievequadrantoperation.Butbecauseofthismethodusingthyristoramountismorecomplex,themaincircuit,andtheoutputpowerfrequencylimitbyfrequency,generallynothigherthan1/2ofthegridfrequency,sopayaacindutionmotorspeedinverterinaspectsoflowpowertransmission,mainlyusedforhighstartingtorque,especiallytheoccasion.Payaconverteriscurrentlyhasbeenthemainformofvariablefrequencypower,thiswaymustthroughtheAC/DCandAC/DCpowertransformationtwice.Efficiencyislower.Buttheformerleveldoesnotaffectthemainsinterference,theoutputwaveformafterclass,widefrequency.TheAC/DCconverterisalwaysaintothecurrentinverterpowertoform,thesoilmustbethroughtheAC/DCandAC/DCpowertransformationtwice.Efficiencyislower.Buttheformerleveldoesnotaffectthemainsinterference,theoutputwaveformafterclass,widefrequency.AC/DCAlternatingcurrenttodirectcurrent,namelytoAC/DCtransformation.Thisfunctiontransformcircuitcommonlycalledrectifiercircuit.IntheprocessoftransformationofAC/DCfrequencyconversion,oftenintroducedtoreduceweightandvolumeofpowerequipment,andimproveefficiency,improvethedynamiccharacteristics,frequencyconversionpurposesfordecadesKHZtohundredsofKHZ.Inthe1970sbyfrequency50Hzacutilitypowertothedclinearmanostatdevelopmenttoswitchfrequencyfor20kHzdcswitchingpowersupply,knownasthe"revolutionary",butonly20kHzaftertenyearsofswitchpowersupply,thefrequencyconversionto500kHzabove.DC/ACAlternatingcurrent,directcurrentwillbecomenamelyDC/ACconversion.Thisfunctiontransformcircuit,commonlyknownastheinverter.Invertercircuitcanbefixeddcvoltagetransformforfixedamplitudeandfrequencyoftheacvoltage,alsowilltransformintoitsamplitudeandfrequencyadjustablevoltage,whichoftencalledinverter.Inverterpowerelectronicsdeviceistheimportantcomponentofuninterruptedpowersupply,electricitytransmission,andmanyotherequipmentm-frequencypowerofthecore,theresearchworkmorepeople'sattention,thefocusofresearchishowitisconvenienttoadjusttheinverterpowersupplyoutputvoltageandfrequency,andlowerharmoniccontent,improvingtheoutputwaveform.Sofar,thelowerharmoniccontentandadjusttheoutputvoltage(orfrequency)commonmeasuresare:1)ontheswitchtubeinverterfrequencyPWMinverter,makethepictureforhighfrequencyoutputasPWMwaves.2)bychangingtheinvertercircuittopologystructure,inthecircuittoreconstructtowaveoutputwaveform,reduceladderlow-orderharmoniccontent.PWMtechnologyisusingsemiconductorswitchingdeviceconductionandshutoffthedcvoltageintovoltagepulse,andthroughthecontrolvoltagepulsewidthtoachievethepurposeofvariablefrequencycontroltechnology,a.SPWMsinepulse-widthmodulationisproducedbythecontrolcircuitofagroupofrectangularpulsewidthanddiffer,usedtoapproximatesinesequencevoltagewave.ForhighfrequencyPWMswitch,thehigherthefrequency,thesmallerofharmoniccontent,buttheswitchlossisbiggeralso,unfavorableuseinhigh-powerinverter.Butoftenrequiremultiplewavereconstructionwaytorealizethevoltageinverter.Waveformreconstruction,themorethelowestserieshigherharmonicfrequency,butthemaincircuitandcontrolcircuitismorecomplex,accordingly,thecontrolvoltageregulationisnotveryconvenient,sothiswayinhigh-powerinverterpowersupplyusuallyonly.UsingPWMtoadjustoutputvoltageandlowerharmoniccontentiscurrentlythemostpopulartechnologiesinsmallpowerinverteriswidelyused,PWMmethodofgeneratingmany.FrequencyconversionpoweradoptPWMtechnologyhastwokinds:Apresetcontrolmodeisswitch,alsocalledselectiveharmoniceliminationPWM,theoreticalanalysisshowsthat,in1973,theselectiveharmoniceliminationcontrolstrategycaneffectivelyovercometheseproblems,itonlyneedlessswitchescanbecompletelyeliminateimpulsenumberoflargecapacity,highorderharmoniclowhasachievedverygoodfilteringeffect,switchlowfrequencyandvoltageswitchingloss,utilizationrateishighermanyadvantages,PWMinvertercontrolmethodoftheideal.SelectiveharmoniceliminationPWMcontrolisaPWMcontrolstrategy,thecalculationmethodis:throughtheirbasicPWMcontrolFourieranalysis,Fourierseries,pulse,forunknowndisplacementofcertainharmoniczero,thengetanonlinearequations,theequationsforselectiveharmoniceliminationPWMmodel,accordingtotheresultsofmodel,excludingtheoutputcontrolthesespecificlow-orderharmonic.Theadvantagesoftheselectiveharmoniceliminationcontrolforpeopletorecognizeanddevelopalotofresearchwork,hopethismethodofpracticalapplication.Unfortunately,sofar,selectiveharmoniceliminationmethodisnotreallyintoactualapplication.Accordingtotheideas,selectiveharmoniceliminationcontrolPWMwavesofphaseisobtainedbysolvingthemodelandselectiveharmoniceliminationmodelisasinefunctionofmultivariatenonlinearequations,anditsnumericalsolutionofcomplicatedanddifficultprocess,sothatthesolutionconvergencecalculationinexistingmicroprocessor(MCU)systeminreal-timetofinish,itisverydifficulttoaconsiderableextentrestrictedinthepracticalapplicationofselectiveharmoniceliminationmethod.Nowtheapplicationofthismethodtocontrolsoil,anditsapplicationintheneedtoadjustthesizeoftheconstantfrequencyvoltageconstant-voltagesourcecontrolisfeasible,Certainbeforehandcalculationorrelevantcontrolparametersinthevoltageinmemory,accordingtoactualneeds,theoutputvoltageclassificationwayoftenrequiresalotofstoragespace,andwiththeresolutionofthevoltageregulator,withitsstoragespace.AnotherkindisSPWMscheme,thedisadvantagesofSPWMishardtoobtainhigheramplitude,switchlossisbigger.Throughimprovingtheadvantageisthatitcanreduceswitchingfrequencyandlowharmonicbyadjustingthepulsewidthtoadjustoutputvoltage.OneSPWMinvertermodeanddividedintothreetypes:(1)controlledrectifiervoltageandfrequencyinverter.Voltageandfrequencyfunctionintwolinksfromcontrolcircuit,coordination,simplestructure,convenientcontrol.Duetotheinputdevicecontrolledrectifying,whenusinglinklowvoltage,largeintriggeringAngle,lowinputpowerfactor,besidesmulti-purposethyristorinvertertype2ladderwavecommutation2timesperweek,theinverter,deviceswitchfrequencylowoutputharmonicbig,ofcourse,controllabledevicessuchasIGBTofPWMcontrolbecomespossible,cangreatlyimprovetheperformance,butthecostishigh.(2)Notcontrolledrectifiervoltagerectifying,chopper,inverterfrequencymodulationmode.Becauseofusingdioderectifier,maketheinputpowerfactorimprovement.Duetotheoutputpowerlinkinverterusingthyristor,stillhavethebigoutputharmonic.(3)Isnotcontrolledrectifierrectifier,pulsewidthmodulation(PWM)inverterandrealizeFMmodevoltage.Athighpowerfactorininputdevices,andadoptshighfrequencyinverterswitch,outputandexcellentperformance.SmallharmonicFrequencyconversionpowerapplicationpurposeandfield:Duetotheworld,thepowerindicatorexportmanufacturerneedstosupplyelectricsimulationofdifferentcountries,forengineersinnetworkdesign,development,productionandqualitytestofproductinspection,life,highvoltagesimulationtestapplications/providepurereliable,lowharmonicdistortion,highfrequencyandvoltagestabilityofpoweroutputrateofsinewave,Importoriginalelectricequipment,usersneedtoChinapowergrid,frequencyconversionvariableimportequipment,Meetavionicsandmilitaryequipment,thehighdemand.Mainlyusedformanufacturingorexporttradebusinessofexportproductsofelectricpowertest,debugandusedforprecisioninstrumentpowersupplies.Widelyusedinhomeappliancemanufacturing,motor,electronicsmanufacturing,ITindustry,computerequipment,laboratory,etc.★appliancemanufacturers：airconditioning,coffeemachine,washingmachine,juiceextractor,microwaveoven,taperecorder,refrigerator,DVD,welcome,electricrazoretc.Producttestpower.★electronicsmanufacturerssuchas:electricalswitchingpowersupplies,transformers,electronicballastandACelectricfans,unceasingly,charger,relays,systemofcompressor,motorandpassivecomponentsetc.Producttestpower.★PaintedITindustryandcomputerequipmentmanufacturerssuchas:fax,copymachine,shredders,printers,scanners,cd-rwdrive,servers,anddisplaystheproductssuchastestpower.★L(fēng)aboratorytestsandpaintedunitssuchas:acpowertestandproductlifeandsafetytesting,emctestandOQC(FQC)testandr&d,producttestingandresearchunitbestacpower.★aviation/militaryunitssuchas:theairportfacilities,ship,aerospace,militaryinstituteoftestpower.Etc.中文翻譯變頻電源變頻電源是將市電中的交流電經(jīng)過AC→DC→AC變換,輸出為純凈的正弦波，輸出頻率和電壓一定范圍內(nèi)可調(diào)。它有別于用于電機(jī)調(diào)速用的變頻調(diào)速控制器，也有別于普通交流穩(wěn)壓電源。理想的交流電源的特點(diǎn)是頻率穩(wěn)定、電壓穩(wěn)定、內(nèi)阻等于零、電壓波形為純正弦波（無失真）。變頻電源十分接近于理想交流電源，因此，先進(jìn)發(fā)達(dá)國家越來越多地將變頻電源用作標(biāo)準(zhǔn)供電電源，以便為用電器提供最優(yōu)良的供電環(huán)境，便于客觀考核用電器的技術(shù)性能。變頻電源主要有二大種類：線性放大型和SPWM開關(guān)型。從結(jié)構(gòu)上看，變頻器可分為直接變頻和間接變頻兩類。直接變頻又稱交一交變頻，是一種將工頻交流電直接變換為頻率可控的交流電，中間沒有直流環(huán)節(jié)的變頻形式:間接變頻又稱為交一直一交變頻，是將工頻交流電先經(jīng)過整流器整流成直流，再通過逆變器將直流變換成頻率可變的交流的變頻形式，因此這種變頻方式又被稱為有直流環(huán)節(jié)的變頻。交一交變頻器一般使用的開關(guān)器件是晶閘管，利用電網(wǎng)電壓有自動(dòng)過零并變負(fù)的特點(diǎn)，將晶閘管直接接在交流電源上，使晶閘管能自然關(guān)斷。其過程與可控整流器一樣，不需要附加換流元件，方法簡單，運(yùn)行可靠。而且，交一交變頻器在低頻時(shí)輸出波形接近正弦，且為一次變流，具有較高的效率，還能實(shí)現(xiàn)四象限運(yùn)行。但是由于這種方法使用晶閘管數(shù)量較多，主回路復(fù)雜，且輸出頻率受電源頻率的限制，一般不能高于電網(wǎng)頻率的1/2，所以交一交變頻器在交流異步電機(jī)調(diào)速方面主要用于低速大功率傳動(dòng)，特別是起動(dòng)轉(zhuǎn)矩要求高的場合。交一直一交變頻器是目前變頻電源的主要形式，該方式必須通過AC/DC和DC/AC兩次電能變換。效率稍低。但前級(jí)市電的干擾不會(huì)影響后級(jí)，輸出波形好，變頻范圍寬。AC/DC交一直一交變頻器是目前變頻電源的土要形式，該方式必須通過AC/DC和DC/AC兩次電能變換。效率稍低。但前級(jí)市電的干擾不會(huì)影響后級(jí)，輸出波形好，變頻范圍寬。AC/DC將交流電變?yōu)橹绷麟?，即AC/DC變換。實(shí)現(xiàn)這一功能的變換電路一般稱為整流電路。在AC/DC變換過程中常常引入高頻變換環(huán)節(jié)，達(dá)到減小電源設(shè)備體積、減輕重量、提高效率、改善動(dòng)態(tài)特性等目的，轉(zhuǎn)換頻率一般為幾十千赫至幾百千赫。70年代將由50Hz交流市電供電的直流線性穩(wěn)壓電源發(fā)展到開關(guān)頻率為20kHz的直流開關(guān)穩(wěn)壓電源，被譽(yù)為“20kHz革命”，然而僅僅經(jīng)過10年左右的時(shí)間，開關(guān)電源的轉(zhuǎn)換頻率己經(jīng)達(dá)到500kHz以上。DC/AC將直流電變?yōu)榻涣麟?，即DC/AC變換。實(shí)現(xiàn)這一功能的變換電路，一般稱為逆變器。逆變電路既可將固定的直流電壓變換為固定幅值和頻率的交流電壓，亦可將其變換為幅值和頻率都可調(diào)節(jié)的交流電壓，后者常稱為變頻器。逆變器是電力電子裝置中的重要組成部分，是不間斷電源、交流電氣傳動(dòng)、中頻電源等許多設(shè)備的核心，因而其研究工作倍受人們的關(guān)注，研究的焦點(diǎn)是如何方便地調(diào)節(jié)逆變電源的輸出電壓和頻率，并降低諧波含量，改善輸出波形。迄今為止，降低諧波含量和調(diào)節(jié)輸出電壓(大小或頻率)的常用措施有:1)對(duì)逆變電源的開關(guān)管進(jìn)行高頻PWM調(diào)制，使逆變器輸出為高頻等幅的PWM波。2)通過改變逆變電源主電路拓?fù)浣Y(jié)構(gòu)，在主電路上進(jìn)行波形重構(gòu)以實(shí)現(xiàn)階梯波形輸出，減小低階高次諧波含量。PWM(脈寬調(diào)制)技術(shù)是利用半導(dǎo)體開關(guān)器件的導(dǎo)通與關(guān)斷把直流電壓變成電壓脈沖列，并通過控制電壓的脈沖寬度以達(dá)到變壓變頻目的的一種控制技術(shù)。SPWM(正弦脈寬調(diào)制)是由控制回路產(chǎn)生一組等幅而不等寬的矩形脈沖序列，用來近似正弦電壓波。對(duì)于高頻PWM調(diào)制來說，開關(guān)頻率越高，諧波含量越小，但開關(guān)損耗也越大，故不宜用在大功率逆變電源中。而波形重構(gòu)方式往往需要多個(gè)逆變器來實(shí)現(xiàn)電壓的疊加。波形重構(gòu)的級(jí)數(shù)越多，出現(xiàn)的最低諧波次數(shù)越高，但主電路和控制電路也越復(fù)雜，相應(yīng)地控制難度也越大，輸出電壓的調(diào)節(jié)也不甚方便，因此這種方式通常只在大功率逆變電源中采用。利用PWM調(diào)制來調(diào)節(jié)輸出電壓和降低諧波含量是目前最為普及的技術(shù)，在中小功率逆變電源中應(yīng)用非常廣泛，PWM的生成方法也很多。變頻電源采用的脈寬調(diào)制技術(shù)有兩種:一種是開關(guān)點(diǎn)預(yù)置控制方式，也叫消諧PWM，理論分析表明，早在1973年提出的消諧控制策略能有效地克服上述問題，它只需要較少的開關(guān)脈沖數(shù)即可完全消除容量較大的低階高次諧波，取得很好的濾波效果，具有開關(guān)頻率低、開關(guān)損耗小、電壓利用率高等許多優(yōu)點(diǎn)，是實(shí)現(xiàn)逆變電源PWM控制的理想方法。消諧PWM控制就是一種經(jīng)過計(jì)算的PWM控制策略，其基本方法是:通過PWM控