电子节气门控制系统设计

电子节气门控制系统设计摘要I摘要电子节气门产品自20世纪80年代问世以来，已逐渐应用到各种中、高级轿车中。相对于传统的机械式节气门，电子节气门系统(ETCS)能根据驾驶员的驾驶意图以及整车行驶状况确定节气门的最佳开度，保证车辆具有最佳的动力性和燃油经济性，并能够为怠速控制(IDL)、驱动防滑控制(ASR)和巡航控制(CCS)等电子控制功能的实现奠定基础，从而提高安全性和乘坐舒适性。同时，对于混合动力汽车，为了实现能量的管理和分配，电子节气门也成为了必然的选择。本文对电子节气门系统进行了研究和开发，为电子节气门在混合动力轿车上的应用奠定了基础。本文分析了电子节气门系统的工作原理、基本结构以及机械结构中存在的非线性因素和各自的特性，如复位弹簧、气流的冲击、库伦+粘滑摩擦等。测定电子节气门的关键参数，建立了电子节气门系统的数学模型。为了适应电子节气门控制系统的快速动态特性，抑制由于电子节气门体的非线性因素对控制特性的影响，提出了一种新的模糊PID复合控制策略，通过模糊控制提高电子节气门系统的动态性能，用智能积分PID控制保证系统的稳态能，利用权重因子函数改善控制切换过程。电子节气门控制器采用飞思卡尔公司的MC9S12DG128单片机作为主控芯片,同时硬件系统还包括控制器的供电电源模块、直流电机的脉宽调制驱动模块、串行通信模块和CAN总线通信模块等。采用CodeWarrior编译的程序软件，完成了控制功能和调试功能。为了对系统状态实时显示和故障报警，以及在控制过程中进行数据采集，本文开发出基于LabWindows/CVI的串口通信系统。试验结果表明:模糊PID复合控制相对于PID控制和智能积分PID控制能够较精确地控制节气门开度，减小超调量，瞬态误差较小，滞后时间较短。所开发的模糊PID复合控制器能够完成电子节气门系统的控制功能要求。关键词：电子节气门；非线性；模糊PID复合控制策略AbstractIIAbstractSincetheelectronicthrottleproductwasdevelopedintheeightiesofthetwentiethCentury,ithasgraduallybeenappliedtohigh-gradeautomobile.Relativetothetraditionalmechanicalthrottle,theelectronicthrottlecontrolsystemcansensethedriveintentionfromthedriverandthecurrentsituationoftheauto,andthendecidethecorrectthrottle’sposition,sothatthedynamicperformanceandfueleconomycanbeimproved.Furthermore,it'shelpfultorealizesomeelectroniccontrolfunction,suchasIDL,ASRandCCS,therebythesecurityanddrivingcomfortcanbeimproved.Withtheappearanceofhybridvehicle,electronicthrottlebecomesaninevitablechoiceforthepowercontrolandmanagementforhybridvehicle.Inthispaper,theelectronicthrottlecontrolsystemwasresearchedanddeveloped,whichlaidthefoundationsofapplyingtheETCStovehicle.Theprincipleandbasicstructureoftheelectornicthrottlecontrolsystem(ETCS)wasanalyzed.Thenonlinearitycharacteristicsincludingnonlinearspring,aerodynamicimpact,coulombandviscousfrictioninthemechanicalpartofthethrotlebodywasstudiedtoo.AftertheanalysisoftheETCS,thekeyparametersofthethrottlewasmeasured.Thenumericalmodeloftheelectronicthrottlecontrolwasbuiltup.InordertoadapttheswiftdynamiccharacteristicsofETCSandrestraininfluenceoncontrolperformanceowingtononlinearityfactorsofETCS,anewFuzzy-PIDmultiplecompoundcontrolmethodisproposed.TherobustdynamiccharacteristicofETCSisattainedbyfuzzycontrolandthestaticperformanceisensuredbyintelligentintegralPIDcontrol,whileswitchingprocessbetweentwocontrolmethodsisimprovedbyusingweightingfactorfunction.ThemainmicrochipoftheelectrionicthrottlecontrollerisMC9S12DG128whichismanufacturedbyFreescale.Inthispaper,thepowersupplymodule,DCmotor’sPWMdrivemodule,serialcommunicationmodule,CANbusAbstractIIIcommunicationmoduleandsoon,wasdesigned.Thesoftware,whichisprogrammedwithCodeWarriorsoftwareformicrocontrolleraccomplishedcontrol,functionandserialcommunicationfunction.Inordertodisplaythestateofthesysteminrealtimeandgiveanalarmwhenmalfunctionoccurs,serialcommunicationsystembasedonLabWindows/CVIwasdesigned.TheresultsoftheexperimentsshowthattheFuzzy-PIDmultiplecompoundcontrolmethodcanexactlycontrolthethrottle’sposition,theovershootisreduced,thetransienttrackingerrorissmallandthehysteresisisshort,whilethePIDcontrolmethodandintelligentintegralPIDcontrolmethoddon’tworkwell.SotheETCS’scontrollerwhichwasdevelopedbasedonFuzzy-PIDcontrolstrategycanmeetETCS’sfunctionrequirements.KeyWords:ElectronicThrottle,Nonlinearity,Fuzzy-PIDMultipleCompoundControlStrategy目录IV目录摘要..............................................................................................................IABSTRACT.....................................................................................................II目录............................................................................................................IV第1章引言...................................................................................................11.1电子节气门产生的背景............................................................................11.2电子节气门在国内外的发展状况.............................................................21.2.1电子节气门在国外的发展状况...........................................................21.2.2电子节气门在国内的发展状况...........................................................21.3电子节气门存在的问题及未来的发展趋势...............................................31.3.1电子节气门存在的问题......................................................................31.3.2电子节气门系统发展的趋势...............................................................31.4本设计主要研究工作...............................................................................41.5本章小结.................................................................................................4第2章电子节气门的结构分析及工作原理..................................................................52.1电子节气门系统的结构和工作原理..........................................................52.1.1电子节气门体....................................................................................62.1.2加速踏板...........................................................................................82.1.3电控单元ECU...................................................................................92.2驱动电机的脉冲调制方式................................................................