300w功率因数校正器设计-翻译-switching power supply technology

毕业设计论文外文资料翻译院（系）电子信息系外文出处POWERELECTRONICS第11期附件1原文；2译文2010年03月10日SWITCHINGPOWERSUPPLYTECHNOLOGYCHAPTERISWITCHINGPOWERSUPPLYOVERVIEW1THEEMERGENCEANDDEVELOPMENTOFSWITCHINGPOWERSUPPLYWITHTHELARGESCALEANDRAPIDDEVELOPMENTOFULTRALARGESCALEINTEGRATEDCIRCUIT,ESPECIALLYINMICROPROCESSORSANDSEMICONDUCTORMEMORYDEVELOPMENTANDUTILIZATION,ANDCARRIESANEWGENERATIONOFELECTRONICSYSTEMSPRODUCTSCLEARLY,THEKINDOFBULKYANDHEAVYUSEOFFREQUENCYTRANSFORMERSLINEARREGULATORPOWERSUPPLYISALREADYOUTDATEDINSTEAD,SMALLSIZE,LIGHTWEIGHTANDHIGHEFFICIENCYOFTHEISOLATEDSWITCHINGPOWERSUPPLYISOLATEDSWITCHINGPOWERSUPPLYISTHECOREOFAHIGHFREQUENCYPOWERCONVERSIONCIRCUITSITMAKESACPOWERORMOREEFFICIENTWAYTOPRODUCEASTABLEDCVOLTAGEPASSINGTOADJUSTASEARLYAS70YEARS,WITHTHECONTINUOUSDEVELOPMENTOFELECTRONICTECHNOLOGY,INTEGRATEDSWITCHINGPOWERSUPPLIESHAVEALREADYBEENWIDELYUSEDINCOMPUTER,COLORTV,SATELLITECOMMUNICATIONEQUIPMENT,PROGRAMCONTROLLEDSWITCHES,PRECISIONINSTRUMENTSANDOTHERELECTRONICEQUIPMENTTHISISBECAUSETHESWITCHINGPOWERSUPPLYCANMEETTHEMODERNELECTRONICEQUIPMENTTOAVARIETYOFVOLTAGEANDCURRENTREQUIREMENTSWITHTHEHIGHDEVELOPMENTOFSEMICONDUCTORTECHNOLOGY,HIGHPRESSUREFASTSWITCHINGTRANSISTORSSOTHATNOFREQUENCYSWITCHINGPOWERSUPPLYTRANSFORMERRAPIDPRACTICALUSETHERAPIDDEVELOPMENTOFSEMICONDUCTORINTEGRATEDCIRCUITTECHNOLOGY,ALSOFORTHESWITCHINGPOWERSUPPLYCONTROLINTEGRATEDCIRCUITLAIDTHEFOUNDATIONTOADAPTTOVARIOUSTYPESOFSWITCHINGPOWERSUPPLYCONTROLREQUIREMENTSOFTHEINTEGRATEDSWITCHINGREGULATORCAMEINTOBEING,ITSFUNCTIONSAREBEINGCONSTANTLYIMPROVEDTHELEVELOFINTEGRATIONISALSORISING,FEWERANDFEWEREXTERNALCOMPONENTS,MAKINGSWITCHINGPOWERSUPPLYDESIGN,PRODUCTIONANDADJUSTMENTSINCREASINGLYSIMPLIFIED,COSTCONTINUESTODROPATPRESENTALLOFTHEFEATURESALREADYFORMEDACOMPLETESERIESOFINTEGRATEDSWITCHINGREGULATORSINRECENTYEARS,HIGHTENSIONMOSRAPIDDEVELOPMENTOFHIGHPOWERTUBES,INTURNSWITCHINGPOWERSUPPLYOPERATINGFREQUENCYFROM20KHZTO150A200KHZ,THERESULTISTHATTHEENTIRESWITCHINGPOWERSUPPLIESARESMALLER,LIGHTERANDMOREEFFICIENTPERFORMANCEANDLOWCOSTSWITCHINGPOWERSUPPLYHASREACHEDANUNPRECEDENTEDLEVEL,MAKINGITCOMPETITIVEWITHTHELINEARPOWERSUPPLYWITHALEADINGTRENDOFCOURSE,SWITCHINGPOWERSUPPLYTHATCANBEACCEPTEDBYINDUSTRY,ABOVEALL,ITISSIZE,WEIGHTANDEFFICIENCYADVANTAGESINTHELATE70S,THEPOWEROVERTHE100WSWITCHINGPOWERSUPPLYISCOMPETITIVEBY1980,POWERAT50WANDABOVETHECOMPETITIVECAPACITYWITHTHEIMPROVEMENTOFTHEPERFORMANCEOFSWITCHINGPOWERSUPPLIES,TOTHELATE80S,ELECTRONICDEVICES,POWERCONSUMPTIONTHANTHE20W,WESHOULDCONSIDERTHEUSEOFSWITCHINGPOWERSUPPLYHASINTHEPAST,SWITCHINGPOWERSUPPLYINTHECONTEXTOFHIGHCOSTOFLOWPOWER,BUTINTOTHE90S,ITSAVERYSIGNIFICANTCOSTREDUCTIONOFCOURSE,THISINCLUDESTHEPOWERCOMPONENTS,CONTROLCOMPONENTSANDMAGNETICCOMPONENTS,THECOSTDROPPEDSIGNIFICANTLYINADDITION,THEINCREASEINENERGYCOSTSISTOPROMOTETHEDEVELOPMENTOFSWITCHINGPOWERSUPPLYONEOFTHEFACTORS2ISOLATEDHIGHFREQUENCYSWITCHINGPOWERSUPPLYISOLATEDSWITCHINGPOWERSUPPLYCONVERTERSHAVEMANYFORMSBEDIVIDEDINTOHALFBRIDGE,FULLBRIDGE,PUSHPULL,SINGLEENDEDFLYBACK,SINGLEENDEDFORWARDANDSOONINTHEDESIGNOFAPOWERSOURCE,CONVERTERCIRCUITDESIGNERSTOTAKETHEKINDOFFORM,MAINLYBASEDONCOST,TOACHIEVETHEPERFORMANCEINDICATORSANDOTHERFACTORSTODECIDEVARIOUSFORMSOFPOWERCIRCUITOFTHEBASICFUNCTIONALBLOCKSARETHESAME,BUTTHETECHNICALMEANSTOCOMPLETETHESEFUNCTIONSAREDIFFERENTISOLATEDHIGHFREQUENCYSWITCHINGPOWERSUPPLYCIRCUITHASACOMMONCHARACTERISTICOFHIGHFREQUENCYTRANSFORMERS,DCFROMTHETRANSFORMERSECONDARYWINDINGSOFPULSEVOLTAGERECTIFIERFILTERCAMEABOUTACLINEVOLTAGEFROMTHEGRID,WHETHER,ORTHROUGHTHESTEPDOWNTRANSFORMEROFFIRSTOFALLTOGOTHROUGHRECTIFIER,FILTERCIRCUITINTOACONTAINING“SETTHEPULSEVOLTAGECOMPONENTOFTHEDCVOLTAGE,ANDTHENINTOTHEHIGHFREQUENCYTRANSFORMATIONPARTHIGHFREQUENCYTRANSFORMATIONPARTOFTHECOREISAHIGHFREQUENCYPOWERSWITCHINGELEMENTS,SUCHASTHESWITCHINGTRANSISTOR,FETANDOTHERCOMPONENTS,HIGHFREQUENCYTRANSFORMATIONPARTOFTHEHIGHFREQUENCYHIGHVOLTAGESQUAREWAVE,THESQUAREWAVETOBESENTTOHIGHFREQUENCYHIGHVOLTAGESTEPDOWNTRANSFORMERISOLATIONPRIMARY,SECONDARYINTHETRANSFORMERINDUCEDVOLTAGEISRECTIFIED,FILTEREDAFTERTHELOWVOLTAGEDIRECTCURRENTPRODUCEDINORDERTOADJUSTTHEOUTPUTVOLTAGE,ALLOWINGTHEEXCHANGEOFINPUTANDOUTPUTLOADCHANGE,THEOUTPUTVOLTAGECANMAINTAINASTABLE,WHEREUSINGADEVICECALLEDAPULSEWIDTHMODULATIONCIRCUIT,THEOUTPUTVOLTAGETHROUGHTHESAMPLE,ANDTOSAMPLETHERESULTSFEDBACKTOTHECONTROLCIRCUIT,CONTROLCIRCUITTOCOMPAREITWITHTHEREFERENCEVOLTAGE,ACCORDINGTORESULTSOFTHECOMPARISONTOCONTROLHIGHFREQUENCYPOWERSWITCHINGCOMPONENTS,THERATIOOFTHESWITCHINGTIMETOACHIEVETHEPURPOSEOFADJUSTINGTHEOUTPUTVOLTAGEINTHESQUAREWAVESRISINGANDFALLINGEDGESTHEREAREMANYHIGHORDERHARMONICS,IFTHESEHIGHERTBWAVESBACKTOTHEINPUTACLINE,ITWILLONOTHERELECTRONICDEVICESCAUSINGINTERFERENCETHEREFORE,THEEXCHANGEOFINPUT,WEMUSTSETTHERADIOFREQUENCYINTERFERENCERFLFILTERTOREDUCEHIGHFREQUENCYINTERFERENCECANRECEIVERANGEINADDITION,INORDERTOSECURETHEENTIRECIRCUITTOWORK,BUTALSODESIGNAUXILIARYCIRCUIT,MAINLYINCLUDINGOVERVOLTAGE,OVERCURRENTPROTECTIONCIRCUIT3THETERMINOLOGYUSEDINSWITCHINGPOWERSUPPLYHEREARESOMEOFTHISBOOKTERMINOLOGYUSEDINSWITCHINGPOWERSUPPLY,ANDANEXPLANATIONFORREADERSREFERENCEEFFICIENCYTHEPOWERSUPPLYOUTPUTPOWERANDINPUTPOWERPERCENTAGETHEMEASUREMENTCONDITIONSAREFULLLOAD,THEINPUTACVOLTAGEOFTHESTANDARDVALUEESREQUIVALENTSERIESRESISTANCEITISSAIDTHATTHERESISTANCEOFELECTROLYTICCAPACITORSPRESENTVALUEOFTHEAGGREGATEUNDERNORMALCIRCUMSTANCES,ESRTHELOWERTHEVALUEOFTHECAPACITANCE,THEBETTERTHEPERFORMANCEOUTPUTVOLTAGEHOLDTIMEINTHESWITCHINGPOWERSUPPLYINPUTVOLTAGEISWITHDRAWN,THESTILLMAINTAINITSRATEDOUTPUTVOLTAGEOFTIMESTARTUPSURGECURRENTLIMITINGCIRCUITITBELONGSTOPROTECTIONCIRCUITSITSTARTSWHENTHEPOWERGENERATEDFROMPEAKCURRENTLIMITINGTOPREVENTUNNECESSARYPOWERLOSSINTHEDESIGNOFTHISCIRCUIT,WEMUSTENSURETHEFILTERCAPACITORISFULLYCHARGEDBEFORETHEYARELIMITINGTHEROLEOFPLAYISOLATIONVOLTAGEPOWERSUPPLYCIRCUITANDPOWERINANYPARTOFTHEMAXIMUMVOLTAGEBETWEENTHESUBSTRATEGROUNDORCANBEADDEDTOTHESWITCHINGPOWERSUPPLYINPUTANDOUTPUTDCVOLTAGEBETWEENTHEMAXIMUMLINEREGULATIONOUTPUTVOLTAGEWITHTHEINPUTLINEVOLTAGEWITHINASPECIFIEDPERCENTAGEOFCHANGEONCONDITIONTHATTHELOADANDTHESURROUNDINGTEMPERATUREISKEPTCONSTANTLOADREGULATIONTHEOUTPUTVOLTAGEWITHLOADCHANGEINTHEPERCENTAGEOFDESIGNATEDAREASCONDITIONSARELINEVOLTAGEANDAMBIENTTEMPERATUREREMAINUNCHANGEDNOISEANDRIPPLEATTACHEDTOTHEDCOUTPUTSIGNALONTHEACVOLTAGEANDHIGHFREQUENCYPEAKSIGNALPEAKSMVISUSUALLYMEASUREDISOLATEDSWITCHINGPOWERGENERALLYREFERSTOHIGHFREQUENCYSWITCHINGPOWERSUPPLYITISTHEACPOWERFROMTHEINPUTRECTIFIERANDFILTERDIRECTLYWITHOUTTHEUSEOFLOWFREQUENCYISOLATIONTRANSFORMEROUTPUTTRANSIENTRESPONSETIMEFROMTHEOUTPUTLOADCURRENTSCHANGE,THROUGHTHEREGULATIONOFTHEENTIRECIRCUITTOTHERATEDOUTPUTVOLTAGERECOVERYTIMEREQUIREDOVERLOADOROVERCURRENTPROTECTIONPREVENTOVERLOADING,SOTHATTHERATEDCURRENTISMORETHANTHEORIGINALDESIGNCAUSEDBYDAMAGETOTHECIRCUITPOWERREMOTEDETECTIONVOLTAGEDETECTIONMETHODSTOCOMPENSATEFORTHEPOWEROUTPUTOFTHEVOLTAGEDROPDIRECTLYFROMTHELOADMETHODOFDETECTINGTHEOUTPUTVOLTAGESOFTSTARTATBOOTTIME,ANEXTENDEDSWITCHINGWAVEFORMSOFTHEWORKCYCLEAPPROACHWORKINGWITHTHEPERIODFROMZEROTOITSNORMALOPERATINGPOINTOFTHETIMESPENTELECTROMAGNETICINTERFERENCERADIOFREQUENCYINTERFERENCETHATIS,THOSEFROMTHESWITCHINGPOWERSUPPLYCAUSEDBYTHESWITCHINGELEMENTS,ANDDONOTWANTTOPASSBYANDTRANSMITHIGHFREQUENCYPOWERSPECTRUMFASTSHORTCIRCUITPROTECTIONCIRCUITONEFORPOWERSUPPLYOUTPUTPROTECTIONCIRCUITWHENOVERVOLTAGEPHENOMENON,THEPROTECTIONCIRCUITSTARTS,THEPOWERSUPPLYOUTPUTVOLTAGEOFFASTSHORTCIRCUITDUTYCYCLEINTHEHIGHFREQUENCYSWITCHINGPOWERSUPPLY,THESWITCHINGELEMENTONTIMEANDTHERATIOOFCONVERTERSWORKCYCLE4VOLTAGETIMESTHEVOLTAGERECTIFICATIONASMENTIONEDEARLIER,ISOLATEDSWITCHINGPOWERSUPPLYDIRECTLYTOTHERECTIFIEDINPUTACVOLTAGEWITHOUTTHENEEDFORALINEARLOWFREQUENCYISOLATIONTRANSFORMERMODERNELECTRONICEQUIPMENTMANUFACTURERSAREGENERALLYREQUIREDTOMEETINTERNATIONALMARKETDEMAND,SOTHEYDESIGNEDSWITCHINGPOWERSUPPLYMUSTBEADAPTEDTOTHEWORLDWIDEACINPUTVOLTAGE,USUALLYTHEEXCHANGEOF90130VAND180A260VRANGEINORDERTOACHIEVETWOKINDSOFINPUTPOWERCONVERSION,TOMAKEUSEOFDOUBLEVOLTAGERECTIFICATION5INPUTPROTECTIONDEVICEISOLATEDSWITCHINGPOWERSUPPLYPOWERINCANADA,ITWILLPRODUCEEXTREMELYHIGHSURGECURRENTDESIGNERSNEEDTOTAKESOMEINPUTPOWERLIMITINGMEASURESCANEFFECTIVELYREDUCETHEINRUSHCURRENTTOTHEALLOWABLERANGESURGECURRENTISMAINLYCAUSEDBYTHEFILTERCAPACITORCHARGING,ANDINTURNBEGANTOSWITCHTHEMOMENT,SHOWINGAVERYLOWCAPACITANCEFORACIMPEDANCE,UNDERNORMALCIRCUMSTANCES,ONLYTHEVALUEOFCAPACITANCEE5RIFYOUDONOTTAKEANYPROTECTIVEMEASURES,SURGECURRENT,CLOSETOSEVERALHUNDREDAMPERESUSUALLYTHEREARETWOWIDELYUSEDMEASURES,ONEWAYISTOUSEABIDIRECTIONALTHYRISTORSHUNTRESISTORNETWORKSANOTHERWAYISTOUSEANEGATIVETEMPERATURECOEFFICIENTNTCTHERMISTORUSEDTOINCREASETHEACLINEIMPEDANCE,THEWAVEPOKECURRENTDECREASESTOASAFEVALUERESISTANCETWOWAYSILICONTECHNOLOGYTHEUSEOFTHISINRUSHCURRENTLIMITINGTECHNOLOGY,ITWILLBERESISTANCEINSERIESWITHTHEACINPUTLINEWHENTHEINPUTFILTERCAPACITOR,AFTERFULLYCHARGEDASTHEBIDIRECTIONALTHYRISTORANDRESISTORAREINPARALLEL,ANDCANSHORTCIRCUITRESISTANCEANDTOCARRYOUTTRIAGETHISCIRCUITREQUIRESATRIGGERCIRCUIT,WHENCERTAINPRECONDITIONSAREMET,THETRIGGERCIRCUITTOTRIGGERTHEBIDIRECTIONALTHYRISTORCONDUCTIONDESIGNCHOICESSHOULDBECAREFULLYCONTROLLEDTWOWAYSILICONPARAMETERS,ANDTOADDSUFFICIENTHEATSINK,SINCEINITSTURN,THEYMUSTFLOWTHROUGHALLOFTHEINPUTCURRENT6INPUTVOLTAGEPROTECTIONBETWEENANODEUNDERNORMALCIRCUMSTANCES,THEACLINEVOLTAGEIS115VOR230VORSO,BUTSOMETIMESTHEREAREHIGHPRESSURESPIKESOCCURFOREXAMPLENEARTHEINDUCTIVEPOWERSWITCHWHENTHELIGHTNINGSTORMWEATHERPHENOMENA,ARETOPRODUCEHIGHPEAKFACTORSUFFERFROMSEVERETHUNDERANDLIGHTNINGEFFECTS,HIGHVOLTAGEPOWERLINESPIKESUPTO5KVTHUS,ALTHOUGHTHEVOLTAGESPIKEDURATIONISVERYSHORT,BUTITDOESHAVEENOUGHENERGYTOSWITCHPOWERSUPPLYINPUTFILTER,SWITCHES,TRANSISTORS,ETC,CAUSINGFATALDAMAGETHEREFORE,MEASURESARENEEDEDTOBEAVOIDEDUSEDINSUCHANENVIRONMENTTHEMOSTCOMMONINTERFERENCESUPPRESSIONDEVICESARETHEAUTHORITYOXIDEVARISTORMOVTRANSIENTVOLTAGESUPPRESSORSHOWNINFIGURE2LSHOWS,THEPRESSURESENSITIVERESISTORRVCONNECTEDTOTHEACVOLTAGEINPUTVARISTORPLAYTHEROLEOFAVARIABLEIMPEDANCEINOTHERWORDS,WHENTHEHIGHVOLTAGESPIKESAPPEARINANINSTANTWHENBOTHENDSOFVARISTORSITDRAMATICALLYREDUCEDTOALOWVALUEIMPEDANCE,ELIMINATINGTHESPIKESSOTHATTHEINPUTVOLTAGETOSAFEVALUESINSTANTANEOUSPOWERCONSUMPTIONINTHEPRESSURESENSITIVERESISTOR,THECHOICEOFPRESSURESENSITIVERESISTOR,THEFOLLOWINGSTEPS1SELECTVARISTORVOLTAGERATING,SHOULDBELESSTHANMAXIMUMCIRCUITVOLTAGESTABILITYVALUATIONIS10TO202CALCULATEORESTIMATETHECIRCUITHAVETOBEARTHEGREATESTNUMBEROFINSTANTANEOUSENERGYOFCHAR3NEEDEDTOIDENTIFYTHEDEVICETOWITHSTANDTHEMAXIMUMPEAKCURRENTAFTERTHECOMPLETIONOFTHEABOVESTEPS,YOUCANVARISTORACCORDINGTOTHEMANUFACTURERSPARAMETERSOFANINFORMEDCHOICEINVARISTORDEVICESCHAPTERIIISOLATEDSINGLEENDEDFLYBACKCONVERTERCIRCUITINGLEENDEDFLYBACKCONVERTERCIRCUITATITSINPUTANDOUTPUTCIRCUITISOLATIONMEASURESBETWEENTHELACKOFSECURITYUNDERNORMALCIRCUMSTANCES,ISOLATEDSWITCHINGPOWERSUPPLYARETHEHIGHFREQUENCYTRANSFORMERASTHEMAINISOLATIONDEVICEINTHECIRCUIT,ITISINTHEFORMOFTRANSFORMER,BUTINFACTITISTHEROLEPLAYEDCHOKE,SOTHEYSHOULDCALLITTRANSFORMERSCHOKETHESOCALLEDSINGLEENDED,REFERSTOTHEWORKINTHETRANSFORMERCOREISONLYONESIDEOFITSHYSTERESISLOOPATYPICALSINGLEENDEDISOLATEDFLYBACKCONVERTERCIRCUITSTRUCTUREASSHOWNINFIGURE34THECIRCUITINFIGURE34WORKINGSTATEWAVEFORMSCANBESEENTHATTHECIRCUITWORKSASFOLLOWSWHENTHETRANSISTORVTLTURN,ITISTHEPRIMARYINDUCTANCECOILINTHETRANSFORMERSTOREDENERGYCONNECTEDWITHTHETRANSFORMERSECONDARYDIODEVDISANTIBIASSTATE,THEREFORE,DIODEVDDEADLINEINTHETRANSFORMERSECONDARYCIRCUITNOCURRENTFLOWS,THATIS,NOENERGYTRANSFERTOTHELOADWHENTHETRANSISTORVTLTHEDEADLINEATTHETRANSFORMERSECONDARYINDUCTANCECOILOFTHEVOLTAGEPOLARITYREVERSED,MAKINGDIODEVDCONDUCTION,THEOUTPUTCAPACITORCCHARGING,WITHTHERIGHTLOADRLHASALSOBEENONTHECURRENTILFIGURE21ISOLATEDSINGLEENDEDFLYBACKCONVERSIONCIRCUITS25ANDTHEASSOCIATEDWAVEASTHEISOLATIONTRANSFORMERTINADDITIONTOTHEPRIMARYANDSECONDARYISOLATIONBETWEENSECURITYROLE,ITALSOHASTHEROLEOFTRANSFORMERSANDCHOKE,SOTHEOUTPUTFLYBACKCONVERTERSGENERALLYDONOTNEEDTOADDSOMEINDUCTANCE,BUTINPRACTICALAPPLICATION,OFTENBETWEENTHERECTIFIERANDFILTERCAPACITORPLUSASMALLINDUCTANCECOILTOREDUCETHEHIGHFREQUENCYSWITCHINGNOISEPEAKS21DISPLAYSWITCHINGPOWERSUPPLYCIRCUITDISPLAYOFTHESWITCHINGPOWERSUPPLYCIRCUITHOLDINGPOINTCANBESUMMARIZEDASTHEFOLLOWINGPOINTS1LIGHTWEIGHT,SMALLSIZEASTHELINEOFSEXUALINTERCOURSEANDELIMINATINGTHEBULKYPRESSUREDEVICE,SAVINGTHEENAMELLEDCOPPERWIREANDSILICONSTEELANDTHEREFOREONLYTHEORIGINALWEIGHTOFABOUT1/5VOLUMEHASALSOBECOMEMUCHREDUCED2THEREGULATORWIDERANGEINPUTPOWERVOLTAGEIS260VA110YWITHINTHESCOPECHANGES,THEOUTPUTVOLTAGECHANGESOFONLY2OFTHEFLUCTUATIONSTHEREFORE,ACCESSTOGOODANDSTABLEVOLTAGEOUTPUTBUTALSOINTHEPOWERGRIDVOLTAGECHANGES,VOLTAGEREGULATORCIRCUITSCANALWAYSMAINTAINAHIGHEFFICIENCYOPERATIONBECAUSEOFTHISCHARACTERISTIC,SOTHATTVCANBEPOOR,APOORENVIRONMENTINRURALANDMOUNTAINOUSAREAS,ANDTHEUSEOFHYDRO,WIND,STRUGGLINGTOGENERATEPOWERINREMOTEAREASSUCHASSECURITY,STABILITY,ANDRELIABLEWORK3EFFICIENCY,ASMALLLOSSBECAUSETHECRYSTALCIRCUITTOADJUSTPIPEWORKINTHESWITCHSTATEWORKINGFREQUENCY15HHZAROUND,SOAHIGHCONVERSIONEFFICIENCYCANREACH85THEINTERNALLOSSCANBEREDUCEDTOAMINIMUM4,WORKSAFETYANDRELIABILITYASARESULTOFTHESCRPROTECTIONCIRCUITWHENTHEPOWERSUPPLYCIRCUITSORLINESCANOUTPUTCIRCUITSANDHIGHVOLTAGECIRCUITOCCURSWHENITISCHENEVENWHENTHELOADSHORTCIRCUITCANAUTOMATICALLYCUTOFFTHEPOWER,PLAYEDTHEROLEOFOVERVOLTAGEANDOVERCURRENTPROTECTIONINGENERAL,THEREQUIREMENTSFORITSPROTECTIONCIRCUITISVERYSTRICT5WITHADIRECTINCENTIVELINESWITCHINGPOWERSUPPLYOUTPUTSTAGETVINTHEEFFICIENCYOFSWITCHINGPOWERSUPPLYSWITCHINGFREQUENCYTOBESYNCHRONIZEDWITHTHELINEIFTHESYNCSIGNALWITHTHELINEOFSWITCHINGPOWERSUPPLYTOCONTROLTHEOPERATINGFREQUENCY,SOTHATTHESWITCHINGFREQUENCYSTRICTLYSYNCHRONIZEDWITHTHELINEOFCOLLAR,ANDTHENBILLINGCHEMOTACTICRTIANJISRIDICULEBYTHEIMPULSETOTAKEALOOKATTHEOUTPUTSHAO9TACTION,SOTHATWECANDISPENSELINEOSCILLATIONINCENTIVELEVELANDLINELEVEL,SOTHATTHECIRCUITTELEVISIONSIMPLIFICATION,GREATERRELIABILITY,LOWERTHECOSTUSED22LINESWITCHINGPOWERSUPPLYINCENTIVEADVANTAGESANDDISADVANTAGESOFTHEOUTPUTISASFOLLOWSLINEMONITORLINEOFOSCILLATORPHASEPHASESWITCHINGPOWERSUPPLYDEVICECANBEPLACEDELIMINATINGTHENEEDFORCONTROLCIRCUITSTHISWILLNOTONLYSIMPLIFYTHECIRCUIT,SAVINGCOMPONENTS,BUTALSOIMPROVEWORKEFFICIENCYSWITCHSHORTCIRCUITWHENTHEINCENTIVEFORANTIPOLARITYCIRCUITCUTOFFLINEOFTHEOUTPUTTUBESBUTNOCURRENTFORTHESAMELEVELOFMOTIVATIONCIRCUIT,LINEPIPEANDSWITCHTHEOUTPUTCURRENTINCREASEDRAPIDLYOVERCURRENTPROTECTIONMEASURESSHOULDBETAKENWHENTHESWITCHOPENWHENTHEPOLARITYOFINCENTIVESFORTHESAMECIRCUIT,THEOUTPUTTUBESARECUTOFFLINEINCENTIVESFORANTIPOLARITYCIRCUIT,LINECURRENTOFTHEOUTPUTTUBEGREATUNTILTHESWITCHINGPOWERSUPPLYENERGYSTORAGEINDUCTORINTHEMAGNETICENERGYSTOREDINDEPLETEDDATEASTHELINEOFTHEOUTPUTSTAGEOFTHEEXCITATIONPULSEWIDTHISLIMITED,SOSWITCHINGPOWERSUPPLYPULSEDUTYFACTOROFTHEINCENTIVEVARIABLETHANTHESCOPESUBJECTTOCERTAINRESTRICTIONS,THESCOPEOFITSREGULATIONISNOTVERYWIDETOOVERHAULHASCAUSEDCERTAINDIFFICULTIESSINCESWITCHINGPOWERSUPPLYCIRCUITANDLINESCANNINGCIRCUITCONSTITUTEAWHOLEWORKINGSTATETOCONTAINEACHOTHER,SOREPAIRWORKMOREDIFFICULTTHANTHEAVERAGETVCHAPTERIIIPOWERMARKETOVERVIEWACCORDINGTOELECTRONICINDUSTRIESASSOCIATIONOFJAPAN,PUBLISHEDHISTORICALRECORDS,THEJAPANESEELECTRONICSINDUSTRYPRODUCTIONIN1983TOTALED126648TRILLIONYEN,THEPREVIOUSYEARS1173INDUSTRIALELECTRONICEQUIPMENTINCLUDINGCOMPUTERSANDPERIPHERALEQUIPMENTFORTHECENTERSHOWSAGOODSITUATIONTOREACH46038TRILLIONYEN,IS106THEYEARBEFOREANDDECADENTATTHEGOLDBASE,MORETHANTHEHOMEAPPLIANCESANDELECTRONICCOMPONENTS,TOBECOMETHECENTEROFTHEELECTRONICSINDUSTRYINADDITION,HOUSEHOLDAPPLIANCES,TAPERECORDERSHAVEEMERGEDINUNEXPECTEDPEAK,AMOUNTINGTO835,300,000,000,IS109THEYEARBEFOREREFLECTTHEFACTTHATTHEINDUSTRIALSITUATIONISDUETOPLAYALEADINGROLEINTHEMECHANICALANDELECTRICALINTEGRATIONOFTHE“CONTROLLINGMOTORS“FORTHEDISKMACHINESANDPRINTERSTOHELPEXPANDTHEDEMANDFOROAEQUIPMENT,JUMPEDONSTAGEANDLEAPTOINCREASEITSPRODUCTIONCAPACITYCONSTITUTETHEHEARTOFTHEPOWERELECTRONICSEQUIPMENT,ESPECIALLYSWITCHINGPOWERSUPPLY,ANDTHISMOTORNECKANDNECK,IN84YEARSSIGNIFICANTLYACCELERATETHEDEVELOPMENTOFTIBET,INTHEPASTISALWAYSTOACTASUNSUNGHEROESOFTHEPOWEREQUIPMENT,ABOUTA“STAR“INDUSTRYTRENDSAFFECTINGTODAYSWORLD,REASONISTHATTHERECENTUSERSOFSMALLELECTRONICDEVICESDUETOFUTUREDEMAND,PROMPTINGTHEDEVELOPMENTOFMICROPROCESSINGTECHNOLOGY,HOMEANDINDUSTRIALCOMPONENTS,THEMINIATURIZATIONANDHIGHDENSITYMOUNTINGANDPROMOTINGALARGESCALEINTEGRATIONTHANTHEONEUSEDTOOTHERCOMPONENTSOFTHEPOWERBEHINDTHEDEPARTMENTOFPACKAGESBYTHISSMALLSHADOWOFPOTTERY,LARGEPOOLONCEUSEDSWITCHINGPOWERSUPPLYESPECIALLYINTHEELECTRONICSINDUSTRYTOPLAYTHEROLEOFTHEOFFICEOFTHETRACTORCOMPUTERS,PERSONALCOMPUTERS,WORDPROCESSINGMACHINE,FAX,RIDICULEDANDSOOAEQUIPMENT,TAPERECORDERSJAPANISTHEWORLDSSUPPLYBASE“,ASWELLASROBOTICS,COMMUNICATIONSEQUIPMENT,2GLANDPREPARATIONOFEQUIPMENT,ETCALLSORTSOFGOODSHAVEADOPTEDSTYLESWITCHINGPOWERSUPPLY,UPTOTHEINDUSTRIALSECTORONTHEPROMOTIONOFTHEDEVELOPMENTINITIATIVETHEREFORE,THEFOLLOWINGDESCRIBESONEOFTHEDCPOWERSUPPLY,ESPECIALLYINSWITCHINGPOWERSUPPLYMARKETOVERVIEW,PRODUCTORIENTATIONDCPOWERSUPPLYCANBEDIVIDEDINTOSWITCHINGPOWERSUPPLY,LOSSOFPOWERSUPPLY,CVTHASTHEPOWER,OTHERPOWERSUPPLYCVCC,ETCSWITCHINGPOWERSUPPLYDUETOOADEVICES,TAPERECORDERSANDOTHERDEVICESNOWUSETHISPOWERSUPPLYISTOINCREASEPRODUCTIONANDUSEOFTHISPOWERISINCREASING,ITMAINTAINEDAGROWTHMOMENTUM,BUTTHEOTHERSIDEISALOSSOFPOWERSUPPLY,CVTPOWERAREFORMINGASHARESINSTEADOFALARGETRIBUTARYOFTHESWITCHINGPOWERSUPPLYINTHESWITCHINGPOWERSUPPLYOTHERTHANTHEDCPOWERSUPPLY,INTHEMOMENTUMOFGROWTHISTHEVCRLOSSOFPOWERSUPPLY,PHOTOCOPIERSCVTWITHHIGHPRESSUREPOWERSUPPLY,TEST,TESTSET61,ANDOTHERPHYSICALCHEMICALEQUIPMENTISALSOUSEFULTOUSEASPECIALPOWEROUTLETDCREGULATEDPOWERSUPPLYIN1983THEMARKETSIZEISESTIMATEDAT1700BILLIONYENAMONGTHEM,SWITCHINGPOWERSUPPLYFORTHEL370BILLIONYEN,LOSSOFPOWERSUPPLY14,500,000,000,CVTPOWERSUPPLY100BILLIONYEN,ANDOTHERCVCC,ETC685BILLIONTHESEARETHEEXPORTSTATUSOFDCREGULATEDPOWERSUPPLYSHOULDBECOUPLEDWITHWANGTOMAKETHEMARKETBECONSIDEREDWITHINTHETOTALAMOUNTOFCONSUMPTIONCALCULATIONOFPLANTCONSUMPTIONISCONTROVERSIAL,BUTDUETOTHEESTABLISHMENTOFALARGENUMBEROFPRODUCTIONSYSTEMANDTHESPLEENQIGUANPOWEROFTHEINTERSONGPRICEINCREASEDITSEXPORTSUPPLYWOULDREACHAVALUEOF100,000,000,000SCALE开关电源技术第一章开关电源概述第一节开关电源的产生与发展随着大规模和超大规模集成电路的快速发展，特别是微处理器和半导体存储器的开发利用，孕育了电子系统的新一代产品。显然，那种体积大而笨重的使