第25卷第11期2009年11月电网与清洁能源PowerSystemandCleanEnergyVol.25No.11Nov.2009文章编号:1674-3814(2009)11-0007-06中图分类号:TM615文献标志码:B
单级式光伏逆变研究与MPPT方法
章伟康1,2,褚君浩2,章闻曦3(1.上海交通大学自动化系,上海200083;2.中国科学院上海技术物理研究所,上海200083;3.IllinoisInstituteofTechnology,ChicagoIL60616-3793,America)ResearchonSingle-stagePhotovoltaicInvertersandMPPTMethodZHANGWei-kang1,2,CHUJun-hao2,ZHANGWen-xi3(1.DepartmentofAutomation,ShanghaiJiaoTongUniversity,Shanghai200083,China;2.ShanghaiInstituteofTechnicalPhysics,ofCAS,Shanghai200083,China;3.IllinoisInstituteofTechnology,ChicagoIL60616-3793,USA)
ABSTRACT:Anovelmechanismandmethodforgrid-connectedinversion,inthestablephotovoltaicenvironmentofindividualsinusoidalperiods,basedonbalanceofICF(IntegralChargeFlows)betweenthesolarcellsourceandinversionloadwithnoDC-DCconversion,isproposedandconductedinthispaperforthepurposetoraiseinversionefficiencyandreduceintermediateexchangeofpowerenergyandtheexchangerate.TheconceptoftheexchangeratiooverMPPvoltagelevelVmisintroduced,theinversionprocessofthismethodisanalyzed,andacalculationformulafortheconstrainedexchangeratioisgiven.Theexistenceoftheperiodicstablephotovoltaicconditionisdemonstratedbytheexperimentalfigure.Inthispaper,theinvertermethodwiththefunctionalstartandregulatorofMPPTisstudiedandthestrategyoftheMPP-followinginversecontrolandtheadjustingalgorithmofMPP-to-MPPtransferaresetupusingDPDVM(DifferentialPowerplusDifferentialVoltageMethod).Theexperimentalinvertershowshighinversionefficiencycanbeachievedbyapplyingthesemethodsandalgorithms.KEYWORDS:inversionefficiency;nonDC-DCconversion;MPPT摘要:提出和研究正弦波周期稳幅条件下基于电荷流积均衡(ICF)的零DC-DC变换的并网型逆变机制和方法,旨在减少电能交换环节和次数,以提高电路逆变效率。还提出流积平衡下基于MPP偏置电压Vm的交换比,分析了这种方法的逆变工作过程,得出约束交换比的计算方法。阐述了正弦单周期逆变调制的光伏环境条件,研究由启动和调节环节构成的无DC-DC变换的MPPT逆变方法,分析建立了功率电压法(DPDVM)的MPPT逆变控制策略及MPP转移调节算法流程。电路实验表明,这些方法和算法下逆变电路可取得很高的效率。关键词:逆变效率;零DC-DC变换;MPPT0引言