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毕业设计（论文）三相四桥臂逆变器的控制策略研究系别：机电信息学院专业名称：电气工程及其自动化学生姓名：学号：指导教师姓名、职称：完成日期2011年12月19日I论文题目：三相四桥臂逆变器的控制策略研究专业：电气工程及其自动化本科生：（签名）指导教师：（签名）摘要为了适应平衡或不平衡负载、线性或非线性负载的要求，三相四桥臂逆变器是针对解决三相不平衡负载而提出的一种新型拓扑。这种拓扑最大的优点是在三相负载不平衡时保持三相输出电压的对称输出，而且和其他三相四线制逆变器相比，系统的体积和重量又比较小。首先，本文介绍了三相四桥臂逆变器的发展概况和一些比较常见的拓扑构，同时还介绍了几种三相四桥臂逆变器的调制策略。其次，本文通过建立四桥臂三相逆变器的数学模型，由数学模型可以得到四桥臂三相逆变器中输出电压和电感电流等各个变量之间的关系，从而实现对输出电压的控制。最后，三相四桥臂的控制策略主要有不对称分量法，滞环电流控制，空间矢量控制，PWM控制。电流滞环控制的硬件电路设计简单，但存在开关频率不固定，输出滤波器设计困难，输出波形质量差，空间矢量控制(SVM)技术具有较高的电压利用率，且通过对零矢量的合理控制可以降低谐波含量或降低开关损耗，因此是一种较好的控制方法。为了消除输出相电压的静态误差，本文讨论了一种基于PI调节器改进的电压调节方案。同时，空间矢量控制也可以应用到三相四桥臂逆变器中。此方法具有提高电压利用率，降低总谐波失真，减小开关频率的特点，并且实现简单。通过MATLAB仿真软件对上述的控制系统进行了仿真验证，结果证明了控制方案的有效。关键词:三相四桥臂逆变器；电流滞环;三维SVM控制IISubject:ControlStrategyofThree-PhaseFour-legInverterSpecialty:ElectricalEngineeringandAutomationName:JiaHonghua(Signature)Instructor:ZhangYufeng(Signature)AbstractInordertoadapttothebalanceornotbalancetheload,linearornonlinearloaddemand,threephasefourbridgearminverterissolvetheunbalancedthree-phaseloadandputforwardanewtypeoftopology.Thistopologyisthebiggestadvantagesinthree-phaseloadbalancenotkeepthree-phaseoutputvoltageofsymmetryoutput,andandotherthree-phasefourwireinverter,comparedthebulkandweightofthesystemandsmaller.First,thispaperintroducesthethreephasefourbridgearminverterthedevelopmentsituationandsomeofthemorecommontopologystructure,andalsointroducesseveralthree-phasefourbridgearminvertermodulationofthestrategy.Secondly,thispaperestablishfourbridgethree-phaseinverterarmofthemathematicalmodel,themodelcangetfourbridgethree-phaseinverterarmoftheoutputvoltageandcurrent,inductanceoftherelationshipbetweenthedifferentvariables,soitcanrealizetheoutputvoltagecontrol.Finally,threephasefourarmsofthebridgetotheasymmetriccontrolstrategyofmaincomponentmethod,hysteresiscurrentcontrol,thespacevectorcontrol,PWMcontrol.Currenthysteresiscontrolhardwarecircuitdesignissimple,buttheexistingswitchingfrequencyisnotfixed,outputfilterdesigndifficulties,poorqualityofoutputwaveform,thespacevectorcontrol(SVM)technologyhashighvoltageutilization,andthroughtothezerovectorcanreducethereasonablecontroloftheharmoniccontentorreduceswitchloss,soisabettercontrolmethod.Inordertoeliminatethephasevoltageoutputstaticerror,thispaperdiscussesthePIadjusterbasedonimprovedvoltageregulationscheme.Inthemeantime,thespacevectorcontrolcanalsobeappliedtothreephasefourbridgearminverter.Thismethodisraisingvoltageutilizationrate,reducethetotalharmonicdistortion,reducingswitchfrequency,andthecharacteristicofimplementationissimple.MATLABsimulationsoftwareoftheabovethroughthecontrolsystemissimulated,andtheresultsprovedeffectivecontrolscheme.Keyword:four-legthree-phaseinverter;hysteresiscurrentcontrol;three-dimensionalSVMcontrolIII目录第1章绪论...................................................................................................................................11.1课题背景............................................................................................................................11.2本文的主要研究内容.......................................................................................................2第2章三相四桥臂逆变器的发展概况.......................................................................................32.1三相四线逆变器的拓扑...................................................................................................42.2三相四桥臂逆变器调制策略概况...................................................................................72.2.1对称分量法..............................................................................................................72.2.2电流滞环控制.........................................................................................................82.2.3PWM控制................................................................................................................82.2.4二维空间矢量控制.................................................................................................92.2.5三维空间矢量调制.................................................................................................92.2.6基于载波的谐波注入调制.....................................................................................92.3本章小结..........................................................................................................................10第3章三相逆变器的数学模型.................................................................................................113.1在ABC静止坐标系中建立三相三桥逆变器的数学模型............................................113.2在ABC静止坐标系中建立三相四桥臂逆变器的数学模型[19]..................................153.3三相四桥逆变器在dqo旋转坐标系中的数学模型.....................................................163.4本章小结..........................................................................................................................18第4章三相四桥逆变器的空间矢量调制方案.........................................................................194.1空间矢量调制概述..........................................................................................................194.2空间合成矢量运动轨迹的确定.......................................................................