采用单片机控制的变频调速系统

编号（学号）：12242018毕业论文（设计）（2012届本科）题目：采用单片机控制的变频调速系统学院：信息与电气工程学院专业：农业电气化与自动化姓名：指导教师：完成日期：2012年05月30日I摘要近年来，随着新型电力电子器件的不断涌现和计算机技术的飞速发展，高性能的交流电动机变频调速系统得到了广泛的应用，它的显著的节能效果和灵活的运行方式，让人们耳目一新。本论文首先论述了调速的基础技术，简述了它在我国的发展和应用以及今后在这方面应做的工作；其次对技术，变频电源技术，以及单片机接口技术做一个简单的论述。然后通过系统的主电路、控制电路、电气控制电路以及实现控制系统地阐述，并对调速系统的实施方案进行了论证。调速系统主电路采用了交直交型电路形式，并采用作为主电路的功率开关器件；根据波形的生成原理，配合采用为主动功率器件完成三相异步电动机的交流变频调速。在逆变器主电路中，个的导通和关断由控制来实现。本文通过软件仿真单片机产生可变频率的三角波与三相工频正弦共同组成了模块的信号波。再通过MATLAB仿真可以得到PWM变频调速的结果，最后和通过电路产生PWM控制波所得到的实验结果一致，进一步证明了基于51单片机的异步电动机变频调速PWM调制方法的正确性和可行性。关键词：51单片机；PWM；调速系统IIAbstractRecentlyseveralyears,alongwiththenewelectricpowerelectronicdeviceunceasingemergenceandthecomputertechnologyrapiddevelopment,thehighperformanceexchangeelectricallyoperatedadaptablefrequencymodulationfastsystemobtainedthewidespreadapplication,hisremarkableenergyconservationeffectandthenimblemovementway,havemadetheprofoundimpressiontothepeople.First,thebasictechniqueofspeedcontrolbyfrequencyvariationisintroducedbriefly,andthenthedevelopmentandapplicationinourcountryissummarizedandweshoulddoinfuture;Second,themaincircuit、controlcircuit、electricalcontrolcircuitandsoftwareandhardwareofthecontroldeviceisanalyzedsystematically.Basedontheforegoinganalyses,AC—DC—ACvoltagesourceinverter(VSI)andIGBTdevicesareselectedinthemaincircuit.AccordingtotheSPWMprofileproductionprinciplewithIGBTactivepowerdevicestocompletethethree-phaseasynchronousmotorpwmACvariablespeed.Intheinvertermaincircuit,thesixIGBTturn-onandturn-offthetoachieveSPWMcontrol.ProteussoftwareemulationMCUvariablefrequencytrianglewavewiththree-phasepowerfrequencysinetogethertoformthesignalwaveofSPWMmodule.MATLABsimulationcanbetheresultsofthePWMfrequencycontrol,thelastagreementwithexperimentalresultsobtainedbythePWMcontrolwaveandthroughthecircuit,furtherproofofthecorrectnessandfeasibilitybasedon51microcontrollerforasynchronousmotorofPWMmodulationmethod.Keyword:PWM;Variablefrequencysystem；51microcontrollerIII目录摘要...................................................................................................................................................................IAbstract............................................................................................................................................................II第一章概述................................................................................................................................................11.1PWM调速系统的组成和功能......................................................................................................11.1.1载波与信号波的产生..........................................................................................................11.1.2PWM信号模块....................................................................................................................11.1.3负载模块..............................................................................................................................21.2单片机概述.....................................................................................................................................21.2.1单片机及其发展历程..........................................................................................................21.2.2单片机的应用领域及发展趋势..........................................................................................21.3计算机仿真概述.............................................................................................................................31.4交流调速系统的发展概述.............................................................................................................31.4.1电力拖动发展过程..............................................................................................................31.4.2直流调速系统的问题..........................................................................................................41.4.3交流电动机的调速优势......................................................................................................41.4.4异步动机调速发展及特性..................................................................................................51.4.5变频调速的基本控制方式..................................................................................................61.5变频调速系统中的变频电路.........................................................................................................61.5.1变频器的分类......................................................................................................................71.5.2静止型常规变频器及特点..................................................................................................7第二章PWM变频控制技术........................................................................................................................82.1变频调速原理.................................................................................................................................82.2变频器控制方法.............................................................................................................................92.3SPWM模式下交直交变频器工作原理......................