光伏逆变器的发展及优势外文文献翻译

结构与工作原理过有规则地让开关元件重复开关（宽调制（SPWM行和停机功能及最大功率跟踪控制功能。、自动运行和停机功能0、最大功率跟踪控制功能太阳电池组件的输出是随太阳辐射强度和太阳电池组件自身温度（芯片温系统始终从太阳电池组件获取最大功率输出，这种控制就是最大功率跟踪控制。太阳能发电系统用的逆变器的最大特点就是包括了最大功率点跟踪（MPPT）这一功能。工作环境与要求：1.光伏逆变器要求具有较高的效率。由于2011年太阳电池的价格偏高，为了最大限度地利用太阳电池，提高系统效率，必须设法提高逆变器的效率。2.光伏逆变器要求具有较高的可靠性。2012年光伏发电系统主要用于边远地出短路保护，过热、过载保护等。3.端电压的变化范围很大，如12V蓄电池，其端电压可在10V～16V之间变化，出电压的稳定。4.光伏逆变器在中、大容量的光伏发电系统中，逆变电源的输出应为失真度较小的正弦波。这是由于在中、大容量系统中，若采用方波供电，则输出将含有网运行时，为避免与公共电网的电力污染，也要求逆变器输出正弦波电流。word文档可自由复制编辑发展前景光伏并网发电系统就是太阳能组件产生的直流电经过并网逆变器转换成符发电系统，是并网发电的主流。、有逆流并网光伏发电系统电能馈入公共电网，向电网供电卖电；当太阳能光伏系统提供的电力不足时，由电能向负载供电(买电。由于向电网供电时与电网供电的方向相反，所以称为有逆流光伏发电系统。、无逆流并网光伏发电系统网供电，但当太阳能光伏系统供电不足时，则由公共电网向负载供电。、切换型并网光伏发电系统动切换到电网供电一侧，由电网向负载供电;二是当电网因为某种原因实然停电对应急负载的供电。一般切换型并网发电系统都带有储能装置。、有储能装置的并网光伏发电系统word文档可自由复制编辑负载的供电系统。优势（1）利用清洁干净、可再生的自然能源太阳能发电，不耗用不可再生的、资源有限的含碳化石能源，使用中无温室气体和污染物排放，与生态环境和谐，符合经济社会可持续发展战略。（2）所发电能馈入电网，以电网为储能装置，省掉蓄电池，比独立太阳能光伏系统的建设投资可减少达35%一45%，从而使发电成本大为降低。省掉蓄电池避免了蓄电池的二次污染，并可提高系统的平均无故障时间。（3）光伏电池组件与建筑物完美结合，既可发电又能作为建筑材料和装饰建筑物科技含量提高，增加卖点。（4）分布式建设，就近就地分散发供电，进入和退出电网灵活，既有利于降低线路损耗。（5）可起调峰作用。联网太阳能光伏系统是世界各发达国家在光伏应用领域竞相发展的热点和重点，是世界太阳能光伏发电的主流发展趋势，市场巨大，前景广阔。word文档可自由复制编辑ThedevelopmentandadvantageofphotovoltaicinverterStructureandworkingprincipleInverterisakindofthesemiconductordevicecomposedofpoweradjustingdevice,mainlyusedforthedcpowerintoacpower.Generallytheboostercircuitandinverterbridgecircuitcomposition.Boostercircuitthesolarcelldcvoltageboostertotheinverteroutputcontrolthedcvoltage;Inverterbridgecircuitistheboosterofdcvoltageequivalenttoconvertcommonfrequencyacvoltage.Inverterismainlycomposedoftransistorandswitchcomponentisformed,andthroughtheregulartoswitchelementrepeaton-off(ON-OFF),makedcinputintoacoutput.Ofcourse,thissimplybyonoroffcircuittoproducetheinverteroutputwaveformisnotpractical.Generalneedtoadopthigh-frequencypulsewidthmodulation(SPWM),closesinewavethevoltageacrossthewidthchangenarrow,centralsinewavevoltagewidthbroaden,andinthehalfperiodalwayslettheswitchelementaccordingtocertainfrequencyinadirectionaction,sothatformapulsewavetrain(quasisinewave).Thenletthepulsewavethroughthesimplefilterformsinewave.Inverternotonlyhasdirectcommunicationmappingfunction,butalsohasword文档可自由复制编辑maximizesolarcellperformancefunctionandsystemfaultprotectionfunction.Tosumupautomaticoperationandshutdownfunction,maximumpowertrackingcontrolfunction,preventrunseparatelyfunction(gridsystem),automaticvoltageregulationfunction(gridsystem),thedcdetectionfunction(gridsystem),thedcgroundingdetectionfunction(gridsystem).Hereintroduceautomaticoperationandstopfunctionandmaximumpowertrackingcontrolfunction.1automaticoperationandstopfunctionThesunriseinthemorning,thesunradiationintensityincreasing,solarcelloutputhasincreased,whentheinvertertotheoutputpower,theinverterautomaticallystartrunning.Enteraftertheoperation,theinverterandeveryminutemonitoringsolarcellmodule,aslongastheoutputofthesolarcellmoduletheoutputpoweroftheinverterisgreaterthantheoutputpower,inverteriscontinuousrunning;Untilsunsetstop,evenifthedayofovercastandrainyinvertercanalsorun.Whensolarcellmoduleoutputdiminish,inverteroutputclosetozero,inverterandstandbystateformation.2themosthighpowertrackingcontrolfunctionTheoutputofthesolarcellmodulewithsolarradiationintensityandsolarcellmoduleitselftemperature(chiptemperature)andchange.Plus,becauseofsolarcellmodulehasthevoltagewithcurrentincreaseandthecharacteristicsofthedecline,andthereforetherearecangetthemosthighpowerbestworkingpoint.Solarradiationintensityischanging,obviouslythebestworkingpointisalsochanging.Relativetothesechanges,alwaysletsolarcellmoduleoftheworkingpointinthemaximumpowerpoint,thesystemalwaysfromthesolarcellmoduleformaximumpoweroutput,thiscontrolisthemosthighpowertrackingcontrol.Solarpowersystemwithinverteristhebiggestcharacteristicofincludingthemaximumpowerpointtracking(MPPT)thisfunction.Workingenvironmentandrequirements:word文档可自由复制编辑1.Photovoltaicinverterrequirementswithhighefficiency.The2011solarcellpriceisonthehighside,inordertomakethebestuseofsolarcell,andenhancedthesystemefficiency,musttrytoimprovetheefficiencyoftheinverter.2.Photovoltaicinverterarerequiredtohavehighreliability.2012pvpowergenerationsystemismainlyusedinremoteareas,manypowerstationunattendedandmaintenance,whichrequirestheinverterinstrumentshavereasonablecircuitstructure,strictcomponentsselection,andrequirementsforinverterinstrumentsofvariousprotectionfunctions,suchasinputdcpolaritymeetantiprotection,acoutputshortcircuitprotection,heat,overloadprotection,etc.3.Photovoltaicinverterfordcinputvoltagehasawideapplicationrange,becausethesunbatteryterminalvoltagewithloadandsunshineintensityandchange,batteryalthoughtosolarcellvoltageplaysanimportantrole,butduetothebatteryvoltagewithbatteryresidualcapacityandthechangeofresistanceandfluctuation,especiallywhenbatteryvoltageacrosstheagerangechangeisverybig,suchas12vbattery,theterminalvoltagecanbein10v~16vchangesbetween,whichrequirestheinvertermustbeinlargedcinputvoltagerangeensurenormalwork,andensurethestabilityoftheacoutputvoltage.4.Photovoltaicinverterinmediumandlargecapacityofphotovoltaicpowergenerationsystem,theoutputoftheinverterpowersupplyshouldbedistortionsmallersinewave.Thisisdueinlargecapacitysystem,ifyouusethesquarewavepowersupply,theoutputwillcontainmoreharmoniccomponent,thehighharmonicswillgenerateadditionalloss,alotofphotovoltaicpowergenerationsystemloadforcommunicationorinstrumentequipment,theequipmenttopowerqualityhavehigherrequirements,andlargecapacityofphotovoltaicpowergenerationsystemparalleloperation,toavoidandpublicelectricityfromthegridpollution,alsorequiresinverteroutputsinewavecurrent.word文档可自由复制编辑DevelopmentprospectPhotovoltaic(PV)gridgenerationsystemissolarenergycomponentsproducedbydcgridinverterconvertedtoconformtothemainspowerrequirementsofthealternatingcurrent(AC)afterthisdirectaccesstopublicpowergrid.Photovoltaic(PV)gridpowersystemhasalarge,centralizedgridpowerstationaregenerallynationalpowerstation,themaincharacteristicisthepowertodirectdeliverytothepowergrid,thegridunifieddeploymenttotheuserpowersupply;Alsohavedistributedsmallgridgenerationsystem,especiallyPVpowergenerationsystem,buildingintegrationisthemainstreamofthecombinedtothegrid.1currentgridphotovoltaicpowergenerationsystemAcurrentgridphotovoltaicpowergenerationsystem:whenthesolarphotovoltaicsystemgeneratedelectricityplenty,butwillbesurpluspowersupplyintothepublicpowergrid,thegridpowersupply(sellelectric);Whensolarpvsystemprovidespowershortage,thepowertoloadpowersupply(buyelectric).Duetothepowersupplytothepowersupplywiththeopposite,socalledcounter-currentphotovoltaicpowergenerationsystem.2nocurrentgridphotovoltaicpowergenerationsystemNocurrentgridphotovoltaicpowergenerationsystem,solarphotovoltaicpowergenerationsystemevenifthepowerisnotenoughpowersupplytothepublic,butwhenthesolarphotovoltaicsystems,powersupplyisinsufficient,thepublicpowergridtotheloadpowersupply.3switchingtypeparallelinphotovoltaicpowergenerationsystemTheso-calledswitchingtypeparallelinphotovoltaicpowergenerationsystem,isactuallyhastobeautomaticoperationtwo-wayswitchfunction.Oneiswhenthephotovoltaicpowergenerationsystemforcloudydayofovercastandrainy,andtheirownfaultthatgeneratingcapacityisinsufficient,switchercanautomaticallyswitchtothesideofthepowersupply,thepowergridtotheloadpowersupply;Thesecondisword文档可自由复制编辑thepowerforsomereasonrealitypower,photovoltaicsystemcanautomaticallyswitchpowerandphotovoltaicsystemseparationandbecameanindependentphotovoltaicpowergenerationsystemworkingcondition.Someswitchingtypephotovoltaicpowergenerationsystem,stillcanbeinwhentodisconnectthepowersupplyforgeneralload,connectthepowersupplytoemergencyload.Generalswitchtypecombinedtothegridsystemwithenergystoragedevice.4astoragedevicegridphotovoltaicpowergenerationsystemAstoragedevicegridphotovoltaicpowergenerationsystem:isintheaboveseveralkindofphotovoltaicpowergenerationsystemaccordingtotheneedconfigurationenergystoragedevice.Withenergystoragedeviceofphotovoltaicsysteminitiativeisstronger,whenthepowergridinpower,powerbrownoutsandfault,independentoperation,thenormalpowersupplytotheload.Sowithastoragedevicegridphotovoltaicpowergenerationsystemcanbeusedasemergencycommunicationpowersupply,medicalequipment,gasstations,shelterdirectivesandlighting,andotherimportantoremergencyloadofpowersupplysystem.advantage(1)theuseofclean,renewablenaturalenergy,solarpowerconsumptionnon-renewableresources,limitedcarbonfossilenergy,theuseofnogreenhousegasesandpollutantemission,andecologicalenvironmentharmonious,inlinewiththeeconomicandsocialsustainabledevelopmentstrategy.(2)thepowercanbefedintothegridtopowergridforenergystoragedevice,dispensewithbattery,thanindependentsolarphotovoltaicsystemconstructioninvestmentcanreduce35%