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单相光伏并网逆变器的研究轮机工程学院I摘要能源危机和环境问题的不断加剧，推动了清洁能源的发展进程。太阳能作为一种清洁无污染且可大规模开发利用的可再生能源，具有广阔应用前景。并且伴随“智能电网”理论的兴起，分布式电力系统正日益受到关注，光伏逆变系统作为分布式电力系统的一种重要形式，使得对该领域的研究具有重要的理论与现实意义。论文在分析光伏逆变系统发展现状与研究热点的基础上，探讨了光伏逆变系统的主要关键技术，对直接影响光伏逆变系统的工作效率以及工作状态的最大功率点跟踪控制、光伏逆变器控制等技术进行了详细研究。为研究光伏逆变系统，本文建立了一套完整的光伏逆变系统模型，主要包括光伏电池模块，前级DC/DC变换器，后级DC/AC逆变器，以及相应的控制模块。为了提高系统模型的准确性及稳定性，论文设计了一种输出电压随温度光照改变的光伏电池模型，提出了一种基于Boost升压变换器的最大功率点跟踪（MPPT）控制策略，并且将正弦脉冲宽度调制技术（SPWM）应用于逆变器控制。最后在Matlab/Simulink软件环境下搭建了光伏逆变系统的整体模型，完成系统性的实验验证。经过仿真实验验证，所提出的光伏逆变系统设计方案正确可行，且输出达到了设计要求，为进一步实现并网功能提供了条件，具有较高的实用参考价值。关键词：光伏电池；最大功率点跟踪；光伏逆变系统；正弦脉冲调制技术IIABSTRACTWithintensifyoftheenergycrisisandenvironmentalproblems,thedevelopmentofcleanenergyhasgotapromotion.Thesolarenergyhasabroadapplicationbecauseofitsfriendly-environmentaladvantageandrenewableproperty.WiththepropositionoftheSmartGrid,DistributedPowerSystemhasearnedmoreattention.AsanimportantformofDistributedPowerSystem,photovoltaicinvertersystemisthekeyoftheresearchinthisfield.ThispaperdiscussesthekeytechniquesofphotovoltaicinvertersystemonthebasisofanalysisofdevelopmentandresearchhotspotofPVinvertersystemandtraversesthemaintechniquessuchasmaximumpowerpointtracking(MPPT)whichhasadirectinfluenceonworkefficiencyandworkconditionandtechnologyofPVinverter.InordertoresearchPVinvertersystem,thispaperbuildsanintegralmodel,includingPVbatterymodelandDC/DCconverterandDC/ACsinglephaseinverteraswellascorrespondingcontrolmodels.Inordertoimprovethevalidityandthestabilityofthesystem,thepaperusesaPVbatterymodelwhoseoutputvoltagechangeswithintensifyoftheilluminationandtherealtimetemperature.AndthispaperproposesacontrolmethodofMPPTonthebasisofBoostconverterandappliestheSinusoidalPWMinsinglephaseinvertercontrol.Atlast,wewillbuildanintegralPVinvertersystembyusingMatlab/Simulinksoftware,togetaverificationandvalidation.Throughmanysimulationexperiments,theproposedphotovoltaicinvertersystemdesigniscorrectandfeasible.Andtheoutputindicatorsmeetthedesignrequirements.Thesystempavestheroadtothefurtherimplementandgridconnectionandhasahighpracticalvalue.KEYWORDS:PVbattery；maximumpowerpointtracking(MPPT)；PVinvertersystem；sinusoidalpulsewidthcontrol(SPWM)III目录第1章绪论...........................................................................................................11.1课题背景及意义........................................................................................11.2光伏并网逆变器技术简介........................................................................21.3光伏并网逆变器的国内外现状及发展趋势............................................31.4本文主要研究内容....................................................................................4第2章光伏并网逆变系统分析...........................................................................52.1逆变器拓扑结构........................................................................................52.2并网逆变器输入方式................................................................................52.3并网逆变器的隔离方式............................................................................62.4并网逆变系统的方案及其工作原理.......................................................72.4.1光伏电池的原理及数学模型..........................................................82.4.2前级Boost升压电路工作原理.....................................................102.4.3后级单相全桥逆变器的工作原理................................................112.5最大功率点跟踪模块的原理及分析......................................................122.5.1最大功率点跟踪原理....................................................................122.5.2爬山法...........................................................................................132.6本章小结..................................................................................................15第3章光伏并网逆变器的控制及实现.............................................................163.1并网逆变器的SPWM技术.....................................................................163.1.1SPWM调制技术原理....................................................................163.1.2单相单极性SPWM逆变器...........................................................173.1.3单相双极性SPWM逆变器...........................................................173.2光伏并网逆变器的输出控制..................................................................183.2.1并网逆变器的控制目标................................................................183.2.2并网逆变器的输出控制模式........................................................183.3并网电流闭环控制系统数学模型..........................................................213.4本章小结..................................................................................................24第4章基于SPWM的并网系统MATLAB/Simulink仿真.............................254.1单相光伏并网逆变系统的仿真..............................................................254.2光伏电池模型仿真..................................................................................254.3并网逆变系统的仿真..............................................................................274.4系统仿真结果及分析..............................................................................28结论....................................................................................................................