Active-Control

1NVHActiveControlofVehicleIntakeandExhaustSystem2TheconceptofactivenoisecontrolwasfirstintroducedbyLuegin1933控制装置传感器扬声器•In1950s,Olsondidalotofresearchinduct,room,etc.•Sincethen,theresearchonthisfieldisslowLueg’sConcept3Theprogressonactivecontrolisslowuntil1980s.Reasons:1.ConstrainedbyElectronictechnologydevelopment.Nofaston-timecontroltechnology2.Theactivecontrolinvolvesmanysciences,suchaselectronictechnology,vibrationandacoustics,signalprocessing3.Whenthetechnologiesareready,costismajorreasonWhyistheactivecontrolneeded?SlowProgressonActiveControl•Enginepowerbecomesstrongerandstronger,thusthenoiseishigherandhigher•Ifconventionalmethodsareused,thepackagespaceislimited•Customersrequirementbecomemoreandmoresensitivetonoiseandvibration•ThePass-bynoiseiscontinuouslyreduced4Open-LoopandCloseloopControl•Openloopcontrol•CloseloopcontrolProcessHInputOutputuyDesiredoutputActualOutputyProcessHKuyyy5FeedbackandFeedforwardControl控制装置误差传感器扬声器控制装置误差传感器扬声器参考传感器•Feedforwardcontrolusesareferencesingle•Feedforwardisaself-adaptivecontrolFeedbackControlFeedforwardControl6ActiveControlandSemi-ActiveControlEngineFrameActuatorControllerExtraEnergySensorEngineFrameActuatorControllerSensorEngineFrameActuatorControllerClose-LoopSemi-ActiveControlActiveControlOpen-LoopSemi-ActiveControl•Mechanicalactuator•Sensor•Electroniccontroller•Extraenergysupplier7Stat-SpaceAnalysis)(tfkxxcxmxxxx2121xx)(121112tfmcxmkxmxxxxxX21umXcmkmX111010BuAXXDuCXYDynamicequation:Stateparameters:State-SpaceEquation:8ActiveNoiseControlinIntakeSystemWhy?•Noisecontrolandpowerlossreductionareapairofcontradiction•Packagespace’slimit.Largeresonatorvolumeisneededforstrongpowerengine发动机控制装置麦克风扬声器Intakefeedforwardcontrol9Example:a4-cylinderorificenoise加上控制的系统原系统声压dB(L)阶次频率(Hz)ActiveNoiseControlinIntakeSystemTheorificenoiseissignificantlyreducedafterthecontrolisadded10AdjustedResonatorZ2ccVlScf2cAclVWhy?Ifasystemhaveseveralnoisepeaks,suchasat66.7Hz,100Hzand200Hz,threeresonatorscouldbeused.1.TheHelmholtzresonatorfrequencydependsonVolume,necksectionareaandnecklength2.Iftheparametersarechanged,thetuningfrequencywillchange11Semi-ActiveControlValve空气过滤器空气过滤器Thepurposeofthe2ndinletorificeistoreducebackpressureathighrpm•Reducepowerloss•Increasenoise12Semi-ActiveMuffler:DualModeMufflerTwoKeyParametersinExhaustSystemDesignLowpowerloss:thebackpressuremustbereducedsimplemufflerlessrestriction---increasetailpipenoiseLownoiseLargemufflersMorerestrictioninmuffler---increasepowerlossTailpipenoiseandpowerlossisaconflictpair.Theymustbetradedoff.Example:Camry(Toyota):quite,11%powerlossTaurus(Ford):loud,6%powerlossSolution:DualModeMuffler13HowDualModeMufflerWorksAtlowenginespeed,thecontrolvalve(red)isclosed.HighrestrictionunderlowflowconditionistocontrollowfrequencynoiseAtmiddletohighenginespeed,thecontrolvalve(red)isopened.Lowrestrictionunderhighflowconditionistominimizebackpressure控制阀控制阀Semi-ActiveMuffler14Semi-ActiveMufflerInternalValveOutsideValve15rpmdB(A)阀门关闭阀门开启阀门关闭阀门开启压力rpmSemi-ActiveMuffler•Noiseproducedbyenginepulse.Valveclosewillbebenefitforinsertloss•Flowexcitednoiseathighrpm.Whenvalveisopen,theflownoiseisreduced•Thevalveisopen,thebackpressuredrops,sothepowerlossisdecreasedBenefittobothTailpipeNoiseandPowerLoss16•BestinNoiseControl/Reduction-NissanShowedUpto20dBTailpipeNoiseReduction(Though5dBWasTypical)•SomePowerImprovement-1987NissanCedricShowed150mmHgReductioninBackpressureat6400RPM•Upto10-30%ReductioninPowerlossw/EqualMufflerVolume•AllowsforReductioninMufflerVolumeApprox.5-10L/ValveBenefitsSemi-ActiveMuffler17Semi-ActiveMuffler•IncreasedWeight•IncreasedWarranty•Complexity/PackagingRequirements(ExternalValve)•Durability•$7-15InternalValve•$15-50ExternalValveDisadvantage18History•Implementedin1987NissanCedric,Gloria,andCimaseries•SAEpapers890612and891356ApplicationsinAsian/EuropeanMarkets•1996BMW328i•FerrariF50•1991-95Mazda929•1995-98HondaAcura•1999HondaAvancier•1990-99Mitsubishi3000(DodgeStealth)•1992-99MitsubishiGalant•1995-99MitsubishiDiamante•1988-92NissanLeopard•1987-91NissanCedric/Gloria/Cima•1993-97SkylinetypeS•2000NissanMaxima•1999VolkswagenLupo•1998VolkswagenPolo•2000Nissan/Sentra•2000InfinityG20•1996-99SuzukiGrandVitars•1997-99ToyotaMarkQualis•1996-99ToyotaLandCruiser/Caldina•1996-99ToyotaMark•1998-99ToyotaCamry•1995-99ToyotaCorolla•1998-99ToyotaLexusRX300•1987-91ToyotaCrown•1992-98ToyotaCamry/Scepter•1998-99RAV4•1996-99ToyotaAvalon•2000ToyotaEcho•2001FordMustang(Japan)•In1999,dualmodemufflershadbeenusedin35models•31modelswereJapanesevehicles•4wereEuropeanvehicles•NoapplicationonAmericanvehicles•GMandFordtriedtousethetechnologySemi-ActiveMuffler19909510010511011512020003000400050006000rpmdB(L)控制关闭控制打开ActiveControlValveActiveMuffler•TheActiveSAMvalveenablesopeningoftheexhaustondemandbyexternalvacuumcontrol.•TheValvecanbeclosedincruisingtoimproveacousticperformance•OpenedatWOTtogainmaximumtorque.20六缸三缸巡航巡航六缸三缸三缸时间VariableCylinderEngineandNoiseInternalNoiseControlImprovefueleconomy•6cylinders:ataccelerationa