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基于CCM的单相BoostPFC电路的设计与仿真摘要近年来，为了避免“电网污染”，如何抑制谐波电流、提高功率因数成了备受关注的问题，而有源功率因数校正技术正是行之有效的方法。尤其是在单相Boost型电路中得到了广泛的应用。它是在桥式整流器与负载接一个DC-DC变换器，应用控制电路的电压电流双环反馈，使电网输入电流波形趋于正弦化且相位保持与输入电压相同，从而大幅降低THD,使得PF接近于1。交流输入电压通过全桥后，得到全波整流电压，再经过MOS管的开关控制使输入电流自动跟随输入电压基准的正弦化脉动，并获得稳定的升压输出，给负载提供直流电压源。本文先简要介绍了功率因数校正技术的现状与发展，着重讨论了有源功率因数校正的原理、拓扑结构、控制方式等内容，然后对控制器UC3854进行了简单的构造分析，最后设计出基于UC3854芯片CCM工作模式的BoostPFC电路。关键词：有源功率因数校正，Boost变换器，电流连续模式，平均电流控制，UC38542ABSTRACTInrecentyears,inordertoavoidgridpollution,howtosuppresstheharmoniccurrent,improvethepowerfactorhasbecomeaconcern,andactivepowerfactorcorrectiontechnologyisaneffectivemethod.Especiallyinsingle-phaseBoost-typecircuithasbeenwidelyused.ItisinthebridgerectifierandtheloadconnectedtoaDC-DCconverter,theapplicationofthecontrolcircuitvoltageandcurrentdoubleloopfeedback,sothatthegridinputcurrentwaveformtendstobesinusoidalandphasetomaintainthesamewiththeinputvoltage,therebysignificantlyreducingtheTHD,makingPFcloseIn1.ACinputvoltagethroughthefullbridge,thefull-waverectifiervoltage,andthenthroughtheMOStubeswitchcontrolsothattheinputcurrentautomaticallyfollowstheinputvoltagereferencesinusoidalpulsation,andobtainastableboostoutputtotheloadtoprovideDCvoltagesource.Inthispaper,thepresentsituationanddevelopmentofpowerfactorcorrectiontechnologyarebrieflyintroduced.Theprinciple,topologyandcontrolmodeofactivepowerfactorcorrectionarediscussedemphatically.Then,thesimplestructureanalysisofcontrollerUC3854iscarriedout.Finally,ChipCCMoperatingmodeBoostPFCcircuit.Keywords:ActivePowerFactorCorrection,Boostconverter,CurrentContinuousMode,Averagecurrentcontrol,UC38541目录1绪论.......................................................................................................................................................11.1功率因数校正的背景意义............................................................................................................11.2功率因数校正的发展概述............................................................................................................11.3功率因数校正的实现方法分类.....................................................................................................21.3.1按PFC电路使用的元器件分类.................................................................................................21.3.2按供电方式分类.........................................................................................................................21.3.3按PFC电路的级联方式分类....................................................................................................21.3.4按PFC电路的电路拓扑结构分类............................................................................................21.4本文所做的主要工作....................................................................................................................22功率因数校正原理...............................................................................................................................42.1功率因数........................................................................................................................................42.1.1功率因数的定义.........................................................................................................................42.1.2功率因数与总谐波失真系数（THD）的关系.........................................................................42.1.3功率因数校正的任务..................................................................................................................42.1.4电源电流波形失真原因简析......................................................................................................52.2有源功率因数校正的基本原理....................................................................................................52.3有源功率因数校正的拓扑结构....................................................................................................62.4有源功率因数校正的工作模式及控制方式................................................................................72.4.1电流断续模式（DiscontinuousCurrentMode,DCM）.............................................................72.4.2电流临界模式（BoundaryConductionMode,BCM）..............................................................82.4.3电流连续模式（ContinuousCurrentMode,CCM）..................................................................93PFC主电路主要元器件的参数设计..................................................................................................133.1本PFC电路的设计指标..............................................................................................................133.2Boost变换器的工作原理.............................................................................................................133.3主电路元器件的参数设计...........................................................................................................153.1.1开关频率的选择........................................................................................................................153.1.2升压电感的选择........................................................................................................................1523.1.3输出电容的选择...............................................................................................