光伏发电系统外文翻译文献

文献信息：文献标题：ANewControllerSchemeforPhotovoltaicsPowerGenerationSystems(光伏发电系统的一种新的控制方案)国外作者：TamerT.N.Khatib，AzahMohamed，NowshadAmin文献出处：《EuropeanJournalofScientificResearch》，2009,Vol.33No.3,pp515-524字数统计：英文1337单词,7006字符；中文2149汉字外文文献：ANewControllerSchemeforPhotovoltaicsPower

GenerationSystemsAbstract:Thispaperpresentsanewcontrollerschemeforphotovoltaic(PV)powergenerationsystems.TheproposedPVcontrollerschemecontrolsboththeboostconverterandthebatterychargerbyusingamicrocontrollerinordertoextractmaximumpowerfromthePVarrayandcontrolthechargingprocessofthebattery.TheobjectiveofthepaperistopresentacosteffectiveboostconverterdesignandanimprovedmaximumpowerpointtrackingalgorithmforthePVsystem.AMATLABbasedsimulationmodeloftheproposedstandalonePVsystemhasbeendevelopedtoevaluatethefeasibilityofthesysteminensuringmaximumpowerpointoperation.1.IntroductionRecently,theinstallationofPVgenerationsystemsisrapidlygrowingduetoconcernsrelatedtoenvironment,globalwarming,energysecurity,technologyimprovementsanddecreasingcosts.PVgenerationsystemisconsideredasacleanandenvironmentally-friendlysourceofenergy.ThemainapplicationsofPVsystemsareineitherstandaloneorgridconnectedconfigurations.StandalonePVgenerationsystemsareattractiveasindispensableelectricitysourceforremoteareas.However,PVgenerationsystemshavetwomajorproblemswhicharerelatedtolowconversionefficiencyofabout9to12%especiallyinlowirradiationconditionsandtheamountofelectricpowergeneratedbyPVarraysvariescontinuouslywithweatherconditions.Therefore,manyresearchworksaredonetoincreasetheefficiencyoftheenergyproducedfromthePVarrays.ThesolarcellV-Icharacteristicsisnonlinearandvarieswithirradiationandtemperature.ButthereisauniquepointontheV-IandP-Vcurves,calledasthemaximumpowerpoint(MPP),atwhichatthispointthePVsystemissaidtooperatewithmaximumefficiencyandproducesitsmaximumpoweroutput.ThelocationoftheMPPisnotknownbutcanbetracedbyeitherthroughcalculationmodelsorsearchalgorithms.Thus,maximumpowerpointtracking(MPPT)techniquesareneededtomaintainthePVarray'soperatingpointatitsMPP.ManyMPPTtechniqueshavebeenproposedintheliteratureinwhichthetechniquesvaryinmanyaspects,includingsimplicity,convergencespeed,hardwareimplementationandrangeofeffectiveness.However,themostwidelyusedMPPTtechniqueistheperturbationandobservation(P&O)method.ThispaperpresentsasimpleMPPTalgorithmwhichcanbeeasilyimplementedandadoptedforlowcostPVapplications.TheobjectiveofthispaperistodesignanovelPVcontrollerschemewithimprovedMPPTmethod.TheproposedstandalonePVcontrollerimplementationtakesintoaccountmathematicalmodelofeachcomponentaswellasactualcomponentspecification.Thede-deorboostconverteristhefront-endcomponentconnectedbetweenthePVarrayandtheload.Theconventionalboostconvertermaycauseseriousreverserecoveryproblemandincreasetheratingofalldevices.Asaresult,theconversionefficiencyisdegradedandtheelectromagneticinterferenceproblembecomessevereunderthissituation.Toincreasetheconversionefficiency,manymodifiedstep-upconvertertopologieshavebeeninvestigatedbyseveralresearchers.Voltageclampedtechniqueshavebeenincorporatedintheconverterdesigntoovercometheseverereverse-recoveryproblemoftheoutputdiodes.Inthispaper,focusisalsogivenintheboostconverterdesign.AnotherimportantcomponentinthestandalonePVsystemsisthechargecontrollerwhichisusedtosavethebatteryfrompossibledamageduetoover-chargingandover-discharging.Studiesshowedthatthelifetimeofabatterycanbedegradedwithoutusingachargecontroller.TheproposednewcontrollerschemeforthestandalonePVsystemcontrolsboththeboostconverterandthechargecontrollerintwocontrolsteps.ThefirststepistocontroltheboostconvertersoastoextractthemaximumpowerpointofthePVmodules.Here,ahighstep-upconverterisconsideredforthepurposeofsteppingupthePVvoltageandconsequentlyreducingthenumberofseries-connectedPVmodulesandtomaintainaconstantdcbusvoltage.AmicrocontrollerisusedfordataacquisitionthatgetsPVmoduleoperatingcurrentandvoltageandisalsousedtoprogramtheMPPTalgorithm.Thecontrolleradoptsthepulsewidthmodulation(PWM)techniquetoincreasethedutycycleofthegeneratedpulsesasthePVvoltagedecreasessoastoobtainastableoutputvoltageandcurrentclosetothemaximumpowerpoint.Thesecondcontrolstepistocontrolthechargecontrollerforthepurposeofprotectingthebatteries.BycontrollingthechargingcurrentusingthePWMtechniqueandcontrollingthebatteryvoltageduringcharging,voltageshigherthanthegassingvoltagecanbeavoided.2.DesignoftheProposedPhotovoltaicSystemMostofthestandalonePVsystemsoperateinonemodeonlysuchthatthePVsystemchargesthebatterywhichinturnssupplypowertotheload.Inthismodeofoperation,thelifecycletimeofthebatterymaybereducedduetocontinuouscharginganddischargingofthebattery.TheproposedstandalonePVsystemasshownintermsofablockdiagraminFigure1isdesignedtooperateintwomodes:PVsystemsuppliespowerdirectlytoloadsandwhentheradiationgoesdownandtheproducedenergyisnotenough,thePVsystemwillchargethebatterywhichinturnssupplypowertotheload.Tomanagethesemodesofoperation,acontrollerisconnectedtotheboostconverterbyobservingthePVoutputpower.Figure1:ScheniiiticdiagramoftheproposedPVsystemClientsTlWLPWMvfVpvMicmcomtrylkr3・MethodologyForthepurposeofestimatingthemathematicalmodelsdevelopedfortheproposedstandalonePVsystem,simulationswerecarriedintermsoftheMATLABcodes.EachPVmoduleconsideredinthesimulationhasaratingof80Wattat1000W/m2,21.2Vopencircuitvoltage,5Ashortcircuitcurrent.ThePVmoduleisconnectedtoablockofbatterieswithofsizing60Ah,48V4.ResultsandDiscussionThesimulationresultsofthestandalonePVsystemusingasimpleMPPTalgorithmandanimprovedboostconverterdesignaredescribedinthissection.SimulationswerecarriedoutforthePVsystemoperatingabove30oCambienttemperatureandunderdifferentvaluesofirradiation.Figure9showsthePVarrayI-Vcharacteristiccurveatvariousirradiationvalues.Fromthefigure,itisobservedthatthePVcurrentincreaselinearlyastheirradiationvalueisincreased.However,thePVvoltageincreasesinlogarithmicpatternastheirradiationincreases.Figure10showsthePVarrayI-Vcharacteristiccurveatvarioustemperaturevalues.Itisnotedfromthefigurethat,thePVvoltagedecreasesastheambienttemperatureisincreased.

14).50Figure2:1-VcurvesatvariousradiationvaluesiS.5DD5ID1E2CVcltsge14).50Figure2:1-VcurvesatvariousradiationvaluesiS.5DD5ID1E2CVcltsge5554535255.43.2<+nuFigure3:1-VcurvesatdiffeienttemperatvievaluesQ10152025VoltageFigure4comparesthePVarrayP-VcharacteristicsobtainedfromusingtheproposedMPPTalgorithmandtheclassicalMPPTP&Oalgorithm.Fromthisfigure,itcanbeseenthatbyusingtheproposedMPPTalgorithm,theoperatingpointofPVarrayismuchclosertotheMPPcomparedtotheusingtheclassicalP&Oalgorithm.Figure4:ComparingP-Vcharacteristics<-ppMMPPbyclasicalmethod20Voltage<-ppMMPPbyclasicalmethod20VoltageT/MPPbyproposedmethodInaddition,theproposedboostconverterisabletogiveastableoutputvoltageasshowninFigure5.IntermsofPVarraycurrent,itcanbeseenfromFigure6thatthePVcurrentisclosertotheMPPcurrentwhenusingtheimprovedMPPTalgorithm.Thus,thetrackoperatingpointisimprovedbyusingtheproposedMPPTalgorithm.IntermsofefficiencyofthestandalonePVsystemwhichiscalculatedbydividingtheloadpowerwiththemaximumpowerofPVarray,itisnotedthattheefficiencyofthesystemisbetterwiththeproposedMPPTalgorithmascomparedtousingtheclassicalP&OalgorithmasshowninFigure7.Figure5:BoostconverteroutputvoltageFigure6:ComparingPVcurrentsFigure6:ComparingPVcurrentsGM血讪Figure7:ComparingefficiencyofPVsystem700900G—■—700900G—■—'WithproposedinethodVAthclassicinethod11005.ConclusionThispaperhaspresentedanefficientstandalonePVcontrollerbyincorporatinganimprovedboostconverterdesignandanewcontrollerschemewhichincorporatesbothasimpleMPPTalgorithmandabatterychargingalgorithm.ThesimulationresultsshowthatthePVcontrollerusingthesimpleMPPTalgorithmhasprovidedmorepowerandbetterefficiency(91%)thantheclassicalP&Oalgorithm.Inaddition,theproposedboostconverterdesigngivesabetterconverterefficiencyofabout93%.SuchaPVcontrollerdesigncanprovideefficientandstablepowersupplyforremotemobileapplications.中文译文：光伏发电系统的一种新的控制方案摘要：本文提出了一种新的光伏（PV）发电系统控制器方案。所提出的PV控制器方案通过使用微控制器来控制升压转换器和电池充电器，以便从PV阵列提取最大功率并控制电池的充电过程。本文的目的是提出一种具有成本效益的升压转换器设计和用于PV系统的改进的最大功率点跟踪算法。已经开发了基于MATLAB的独立光伏系统的仿真模型，以评估系统在确保最大功率点操作的可行性。1.引言最近，由于环境、全球变暖、能源安全、技术改进和降低成本有关的问题，PV发电系统的安装正在快速增长。光伏发电系统被认为是一种清洁环保的能源。光伏系统的主要应用是独立或并网配置。独立的光伏发电系统作为偏远地区不可或缺的电源是有吸引力的。然而，PV发电系统具有两个主要问题，其涉及约9至12%的低转换效率，特别是在低照射条件下，并且由PV阵列产生的电功率的量随天气条件连续变化。因此，进行了许多研究工作以增加从PV阵列产生的能量的效率。太阳能电池V-I特性是非线性的，随着辐射和温度而变化。但是在V-I和P-V曲线上有一个独特的点，称为最大功率点（MPP），在该点PV系统被称为以最大效率运行并产生其最大功率输出。MPP的位置是未知的，但可以通过计算模型或搜索算法来跟踪。因此，需要最大功率点跟踪（MPPT）技术来将PV阵列的工作点维持在其MPP。在文献中已经提出了许多MPPT技术，其中技术在许多方面各有不同，包括简单性、收敛速度、硬件实现和有效范围。然而，最广泛使用的MPPT技术是扰动和观察（P&O）方法。本文提出了一个简单的MPPT算法，可以轻松实现和采用低成本光伏应用。本文的目的是设计一种改进的MPPT方法的新型PV控制器方案。提出的独立光伏控制器考虑到实现数学模型每个组件以及实际的组件规范。DC-DC或升压转换器是连接在PV阵列和负载之间的前端组件。传统的升压转换器可能导致严重的反向恢复问题，并增加所有器件的额定值。因此，在这种情况下，转换效率降低，并且电磁干扰问题变得严重。为了提高转换效率，若干研究人员对许多改进的升压转换器拓扑结构进行了研究。电压钳位技术已被纳入转换器的设计，以克服输出二极管的严重反向恢复问题。在本文中，重点也是给出升压转换器设计。独立光伏系统的另一个重要组件是充电控制器，用于避免电池由于过多充电和过多放电而可能造成的损坏。研究表明，在不使用充电控制器的情况下，电池的寿命可能会下降。所提出的用于独立光伏系统的新控制器方案在两个控制步骤中控制升压转换器和充电控制器。第一步是控制升压转换器，以提取光伏组件的最大功率点。在这里，高升压型转换器被认为是对加强光伏电压起作用，从而降低了串联光伏组件的数量，并保持一个恒定的直流总线电压的目的。微控制器用于获取PV组件工作电流和电压的数据采集，也用于对MPPT算法进行编程。控制器采用脉冲宽度调制（PWM）技术以随着PV电压降低而增加所产生的脉冲的占空比，以便获得接近最大功率点的稳定的输出电压和电流。第二控制步骤是为了保护电池而控制充电控制器。通过使用PWM技术控制充电电流并在充电期间控制电池电压，可以避免高于放气电压的电压。光伏系统设计的提出大多数独立的光伏系统仅以一种模式操作，使得光伏系统对电池充电，电池又向负载供电。在这种操作模式中，由于电池的连续充电和放电，电池的寿命周期时间可能减少。根据图1中的框图所示，所提出的独立的光伏系统被设计成两种模式操作：光伏系统直接向负载供电，而当辐射下降并且所产生的能量不足时，光伏系统将充电电池，继而向负载供电。为了管理这些操作模式，通过观察光伏输出功率，将控制器连接到升压转换器。

團1;克r的團1;克r的兰伏丢疑示意團1/他MicrocontrollerBaileries计算方法为了估算所提出的独立光伏系统开发的数学模型这一目的，根据MATLAB代码进行了模拟。在模拟中每个光伏组件考虑在lOOOw/m2、21.2V开路电压、5A短路电流下的额定功率为