LLC谐振网络(变压器)的计算公式

HALF-BRIDGELLCRESONANTCONVERTERL6599-basedDesignSpreadsheetVersion1.0ThisworkbookenablestheusertodesignanL6599-basedsingle-outputhalf-bridgeLLCresonantconverter.Theprocedureisintendedforaconverterworkingwithafront-endPFCpreregulatorprovidingthesupplybustotheresonantstage.Itiscomposedof5worksheets(besidesthepresentone),eachdedicatedtoaspecifictask:♦EL_SPEC:inputofconverter'selectricalspecificationandofsomepre-designchoices♦MOS+OUTPUT_STAGE:selectionofthepowerswitch(MOSFET)andofthesecondaryrectifierandoutputcapacitor♦RES_STAGE:calculationoftheresonantconverterparameters♦L6599:selectionofICbiasingcomponents♦SUMMARY:summarizesthecalculationresultsandshowsthebasicelectricalschematicItisrecommendedtousetheworkbookstartingfromthefirstsheetandproceedingfollowingtheordershown.Ineachworksheet,cyancellsrefertodatathatmustbeenteredbytheUser,yellowcellsrefertocalculationresultswhichneedsafurthercheckorastandardvaluechoice.ELECTRICALSPECIFICATIONS:Converterspecification:NOTES:NominalsupplyBUSvoltage:V.dc.nom=390(V)wheretheoperatingfrequencyequalstheresonantfrequencyf.sw=f.rMinimumsupplyBUSvoltage:V.dc.min=320(V)dependingonthehold-upcapabilityofthePFCpre-regulatorMaximumsupplyBUSvoltageV.dc.max=420(V)dependingontheOVPlevelofthePFCpre-regulatorNominaloutputvoltage:V.out=200(V)Maximumoutputpower:P.out=400(W)Outputvoltageripple:ΔVout=100(mV)Expectedefficiency:η%=97.5%onlyresonantconvertercircuitPre-designchoices:Minimumoperatingfrequency:f.sw.min=75(kHz)Maximumoperatingfrequency:f.sw.max=150(kHz)Straycapacitanceathalf-bridgenode:C.stray=120(pF)foreseenvaluewithoutC.osscontributionK.conf=1incaseoffullbridgerectificationK.conf=2incaseoftransformercentertapwindingenterdataintocyancellssuggestion:1:2rangeSecondaryoutputrectifierconfiguration:K.conf=2outputrequirementsenterdataintocyancellsHalf-bridgemosfetstress:I.MOS=2.014(Arms)estimatedmaxoperatingdraincurrentV.DS=420(V)maxoperatingdrain-sourcevoltageV.(br).DSS=500(V)suggestedbreakdownvoltageR.(DS)on=0.300(Ω)suggestedONresistanceat25°CSelectthesuitablemosfetfromYourdata-baseandwritetherequiredparametervaluesbelow:Mosfettype:FillwithyourselectedpartnumberChosenmosfetparameters:R.DS.on=0.35(Ω)ONresistanceat25°C(frommosfetdata-sheet)k.mos=1.6TemperaturemultiplierforRds.ONat100°CC.oss=90(pF)EffectivedraincapacitanceOutputdiodestress:I.DIODE=1.571(Arms)estimatedmaxdiodermscurrentI.D.avg=1.000(Aavg)estimatedmaxdiodeavgcurrentV.RRM=480(V)minimumsuggestedbreakdownvoltage(with20%derating)SelectthesuitablediodefromYourdata-baseandwritetherequiredparametervaluesbelow:Diodetype:FillwithyourselectedpartnumberChosendiodeparameters:V.F=1.06(V)diodeforwarddropthreshold(fromdiodedata-sheet)R.d=36(mΩ)diodedynamicresistanceI.R=240(µA)diodeleakagecurrentPowerlosses:Maxtotalpowerdissipation:P.diss.tot=10.256(W)forexpectedefficiencyηMosfetpowerdissipation:P.d.mos=4.578(W)(totaldissipationofhalf-bridgemosfets)Diodepowerdissipation:P.d.rect=2.394(W)(totaldissipationofoutputdiodes)Outputvoltageripple:ΔVout=100(mV)MaxcapacitorESR:ESR.max=32(mΩ)Capacitorripplecurrent:I.o.ac.max=0.967(A)OUTPUTCAPACITORSELECTION:HALF-BRIDGEMOSFETSELECTION:STP14NK50ZFPSTTH8L06FPOUTPUTDIODESELECTION:Parameterschoice:Resonancefrequency:f.r=118(kHz)selectavaluebetweenf.sw.minandf.sw.msxMarginfactorforQ.minvalue:k.marg=0.94startingvalueintherange:0.80-0.95Calculations:Idealtransformertransferratio:n=0.970Maximumrequiredgain:M.max=1.219Minimumrequiredgain:M.min=0.929Maxnormalizedfrequency:f.n.max=1.271ACequivalentresistance:R.ac=76.649(Ω)Inductanceratio(L.r/L.m):λ=0.202Minimumqualityfactorvalue:Q.zvs=0.441Minoperatingfrequency:f.sw.Min=75.063(kHz)Incasethecalculatedminfrequencyf.sw.MinislowerMinimumnormalizedfrequency:f.n.min=0.636orhigherthantheexpectedfrequencyf.sw.min,pleaseincreaseordecreasetheresonancefrequencyf.r,unlessPleasecheck=f.sw.min=75(kHz)youaccepttheobtainedminimumswitchingfrequencyvalue.Calculatedresonantcapacitorvalue:C.r=39.930(nF)Pleaseusethehigherstandardvalue:C.r.std=40(nF)Transformerturnratio:N.T=1.063Transformerleakageinductance:L.r=45.000(μH)Transformerprimaryinductance:L.p=268.000(μH)PrimarysidermscurrentI.prim.rms=2.859(A)SecondarysidermscurrentI.sec.rms=1.571(A)X=0.088Incasetherelationship:TgΦ≥Xisnotverified,TgΦ=0.094choosealowervaluefork.marg,anditeratetheprocess.Pleasecheck=enterdataintocyancellsHALF-BRIDGERESONANTCONVERTERDESIGN:Minimumoperatingfrequency:f.sw.Min=75.06(kHz)FromresonantstagecalculationsheetMaximumoperatingfrequency:f.sw.max=150.00(kHz)FromelectricalspecsheetStart-upfrequency:f.start=300(kHz)Suggestedvaluethreetofourtimesf.sw.MinSelectCosccapacitor:C.f=470(pF)Typicalvaluesare220÷1000pFMinimumfrequencysettingresistor:R.fmin=9.448(kΩ)PleaseusethenearestvalueR.fmin=10(kΩ)Soft-startfrequencysettingresistor:R.ss=3.337(kΩ)PleaseusethenearestvalueR.ss=3.3(kΩ)Soft-starttimingcapacitor:C.ss=0.909(µF)PleaseusethenearestvalueC.ss=1(µF)Maximumfrequencysettingresistor:IfStand-bypinisconnectedtopin#4:R.fmax_1=10.017(kΩ)PleaseusethenearestvalueR.fmax_1=10(kΩ)IfBurstmodeisused:R.fmax_2=3.756(kΩ)Pl