三相光伏并网逆变器

上海红申电气有限公司摘要I三相光伏并网逆变器研发与智造专业：控制理论与控制工程在职研究生：张秀云（上海红申电气有限公司工程师）指导教师：刘一鸣（教授级高工）摘要光伏并网发电过程是将直流电变为交流电并将能量输送给电网，逆变器是太阳能电池和大电网连接的核心设备，它的稳定性和可靠性决定了输送电能的质量，为了提高发电质量，需要对系统的硬件和软件做深入的分析。本文对这两个方面都做出了比较详细的数学推导，并进行了理论仿真，然后在此基础上搭建了硬件平台，对这些算法进行了初步的验证，给出了相应的实验结果。首先，本文对光伏阵列的结构进行了分析，并搭建了阵列的仿真模型，从仿真模型的P—U曲线可以看出阵列存在最大输出功率，并在此基础之上就最大功率跟踪问题做出了深入思考，在传统的算法基础之上提出了一种算法，仿真表明该算法比传统算法具有更好地跟踪效果。接着，本文对逆变器的拓扑结构做出了说明，并选择了单级式的拓扑结构作为本文研究对象。对于L型和LCL型的滤波器结构而言，其数学模型是不同的，并网电流的控制算法也要做相应的改变。对于电压型逆变器，本文采用直接电流控制，分别对滞环控制和三角波比较控制做出了分析。特别地，对于LCL型滤波器在同步坐标系下因其复杂的解耦，本文引入了PR控制，搭建了matlab仿真对上述算法进行了仿真和对比分析。最后，本文就L，LCL滤波器还有采样电路进行了理论计算，搭建了实验平台，用TMS320F2812做核心控制器对理论算法进行了初步的验证，给出了实验波形。关键词：光伏并网发电最大功率点跟踪直接电流控制PR控制红申电气上海红申电气有限公司摘要IIThree-phasedPhotovoltaicGrid-connectedInverterAndControlSpeciality:ControlTheoryandControlEngineeringName:ZhangXiuyunSupervisor:ProfessorWangXiaoleiAbstractThephotovoltaicpowergenerationprocessismakingthedirectcurrenttothealternatingcurrentandtransmissingtothegrid,theinverteristhecoreequipmentoftheconnectionbetweensolarcellsandgrid,itsstabilityandreliabilitydeterminethequalityoftheelectricalenergytransmission.Inordertoimprovethequalityofpowergeneration,ain-depthanalysisonhardwareandsoftwareofthesystemhavedone.Thispaperhavemadeamoredetailedmathematicalderivationandtheoreticalsimulationonthesetwoaspects,havealsomadeapreliminaryvalidationofthesealgorithmsandgiventhecorrespondingexperimentalresultsonahardwareplatform.First,thispaperanalyzesthestructureofthephotovoltaicarray,thenbuildsasimulationmodelofthePVarray.TheexistofmaximumoutputpoweroftheP-Ucurvecanbeseenfromthesimulationmodel,adeepthinkingofthemaximumpowerpointtrackingalsohavedoneonthisbasis,andproposesanewalgorithmsimulationshowsthathasabettertrackingresultscomparedwiththetraditionalalgorithm.Then,thispaperdescribesthetopologyoftheinverter,andselectssingle-stagetopologyasaresearchobject.ForL-andLCL-filterstructure,themathematicalmodelisdifferent,andthenetcurrentcontrolalgorithmsalsoneedtodotheappropriatechange.Inthispaper,directcurrentcontrolisusedonvoltagesourceinverter,andrespectivelyanalysiseshysteresiscontrolandthetrianglewavecomparingcontrol.Inparticular,becausedecouplingoftheLCLtypefilterinthesynchronouscoordinatesystemiscomplicated,thispaperintroducesPRcontrol,setsupamatlabsimulationtosimulateandgivecomparativeanalysisoftheabovealgorithm.Finally,thispapergivestheoreticalcalculationsoftheL-andLCL-filterandsamplingcircuit,buildsanexperimentalplatformusingTMS320F2812ascorecontrollertodoapreliminaryvalidationofthetheoreticalalgorithm,andgivestheexperimental上海红申电气有限公司摘要IIIwaveforms.Keywords：Grid-connectedPhotovoltaicPower；MaximumPowerPointTracking；Directcurrentcontrol；PRcontrol上海红申电气有限公司目录I目录1.绪论·································································································11.1课题研究背景及意义······································································11.2太阳能发展的最新动态···································································11.3简述太阳能电池的分类···································································11.4我国太阳能资源············································································21.5太阳能光伏发电系统的其他应用·······················································21.6本文的所做的工作·········································································32.光伏阵列的电气特性············································································42.1太阳能电池的基本原理···································································42.2光伏阵列的建模和特性分析·····························································42.2.1光伏阵列的数学模型······························································42.2.2不同光照强度下光伏阵列的的I—U及P-U特性特征曲线··················62.2.3不同温度下光伏阵列的I—U及P-U特性特征曲线···························72.3最大功率点控制策略及仿真·····························································82.3.1固定电压法（C&T）······························································82.3.2扰动观测法（perturb&observealgorilhms,P&O）··························82.3.3电导增量法（IncrementalConductance）·····································82.3.4牛顿插值算法（Newtonmethod）·············································92.4本章小结····················································································143.三相单级式光伏并网逆变器的控制策略···················································153.1光伏并网逆变器电力质量技术要求···················································153.2光伏并网逆变器拓扑结构·······························································153.2.1并网逆变器拓扑结构分类·······················································153.2.2本系统的拓扑结构以及分析····················································163.3三相单级式光伏并网逆变器的工作原理············································193.3.1三相半桥L型滤波器数学模型··················································193.3.2三相半桥LCL型滤波器数学模型···············································223.3.3并网电流控制技术································································243.3.4并网逆变器算法的仿真及其分析··············································253.4本章小结····················································································36上海红申电气有限公司目录II4.光伏并网逆变器主电路的搭建················