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毕业论文(设计)学生姓名：学号：所在学院：自动化与电气工程学院专业：自动化设计(论文)题目：光伏逆变器的并网控制仿真指导教师：2011年6月10日摘要世界环境的日益恶化和传统能源的日益枯竭，促使了对新能源的开发和发展。具有可持续发展的太阳能资源受到了各国的重视，各国相继出台的新能源法对太阳能发展起到了推波助澜的作用。其中，光伏并网发电具有深远的理论价值和现实意义，仅在过去五年，光伏并网电站安装总量已达到数千兆瓦。而连接光伏阵列和电网的光伏并网逆变器便是整个光伏并网发电系统的关键。光伏并网逆变器是将太阳能电池所输出的直流电转换成符合公共电网要求的交流电并送入电网的设备。首先介绍了光伏并网逆变器。其次，本文采用直流电压外环、电流内环的双闭环控制方法，既保证了逆变器输出的静态误差为零，又保证了逆变器良好的输出波形。随后，本文详细讨论了并网过程中的软件锁相环技术，对锁相环电路的组成、工作原理进行了研究。本文根据逆变器结构的特点，提出了基于DC-AC单级并网逆变器的结构。在DC-AC转换器中，采用输出电流控制，根据正弦脉冲宽度调制的缺点，提出空间矢量脉宽度调制方法对逆变器进行控制，从而提高直流侧电压的利用率，减少谐波。基于SVPWM的控制原理，在MATLAB_simulink上建立系统模型，并进行了仿真实验。仿真结果表明输出电流与电网电压保持同相位，从而证明了原理的可行性。关键词：光伏发电并网逆变器SVPWM锁相环技术ABSTRACTTheworld'senvironmentisdeterioratingandtheincreasingdepletionoftraditionalenergysourcestopromotethedevelopmentofnewenergydevelopment.Solarenergyresourcesbythecountriesattachimportancetosustainabledevelopment,countrieshaveintroducedanewenergylawhasplayedaroleinfuelingthedevelopmentofsolarenergy.Amongthem,photovoltaicpowergenerationhasfar-reachingtheoreticalvalueandpracticalsignificance,inthepastfiveyearsalone,thetotalphotovoltaicpowerplantinstallationhasreachedthousandsofmegawatts.Connectedphotovoltaicarraysandgridphotovoltaicgrod-connectedinverteristhekeytotheentiregrid-connectedPVsystems.PVgrid-connectedinvertersolarcelloutputDCintoACmeettherequirementsofthepublicgridandintothepowergridequipment.FirstintroducedthePVgrid-connectedinverter.Secondly,theDCvoltageloopandinnercurrentclosed-loopcontrolmethod,bothtoensurezerostaticerroroftheinverteroutput,butalsotoensurethattheinverteroutputwaveform.Subsequently,thedetaileddiscussionofthesoftwarephase-lockedlooptechnologyandnetworkprocess,thecompositionofthephase-lockedloopcircuit,theworkingprincipleofthestudy.Accordingtothecharacteristicsoftheinverterstructure,basedonthestructureoftheDC-ACsingle-stagegrid-connectedinverter.DC-ACconverter,theoutputcurrentcontrol,accordingtotheshortcomingofthesinusoidalpulsewidthmodulation,spacevectorpulsewidthmodulationinvertercontrol,therebyimprovingtheutilizationoftheDCvoltageandreduceharmonics.BasedontheprincipleofSVPWMcontrolinMATLAB_simulinksystemmodelandsimulationexperiment.Thesimulationresultsshowthattheoutputcurrentandgridvoltagetomaintainthesamephase,thusprovingthefeasibilityoftheprinciple.Keywords:Photovoltaicpowergeneration;SVPWM;Grid-connectedinverter;PLL目录摘要..........................................................................................................................IABSTRACT..............................................................................................................II第一章绪论..............................................................................................................11.1光伏发电的研究背景与意义..............................................................................11.2国内外的研究现状..............................................................................................31.2.1国外的研究现状............................................................................................31.2.2国内的研究现状............................................................................................41.3光伏并网逆变器技术.........................................................................................41.4光伏并网逆变器的发展趋势.............................................................................61.5本文主要的研究内容.........................................................................................6第二章并网逆变器的概述..................................................................................72.1并网逆变器..........................................................................................................72.2并网逆变器的结构特点及作用..........................................................................72.3并网逆变器的分类..............................................................................................92.3.1逆变器的拓扑分类........................................................................................92.3.2逆变器的回路方式......................................................................................102.4本章小结............................................................................................................12第三章系统的总体结构设计及工作原理....................................................143.1系统的总体设计................................................................................................143.2系统的总体方案................................................................................................153.3系统的工作原理................................................................................................153.4本章小结............................................................................................................16第四章光伏并网逆变器控制策略的初步研究...........................................174.1光伏并网逆变器控制目标...............................................................................174.2基于SVPWM的电压/电流型并网逆变器控制的研究.................................174.2.1控制系统数学模型.....................................................................................174.2.2PI参数的设计..................................................................