Hybrid-Electric-Vehicles-国外的电动汽车详解资料

HybridelectricvehiclesAnextracreditpresentationbyHarryPapacharissiouWithsupplementationbyAndrewNafalski1HybridelectricvehiclesWhatisaHEV?WhyHEV’sAdvantagesofusingHEV’sTypesofHEV’sHEVcomponentsThefutureofHEV’s2WhatisaHEV?

Hybridelectricvehicles(HEVs)combinetheinternalcombustionengineofanormalvehiclewiththebatteryandelectricmotorofanelectricvehicle.Thisresultsintwicethefueleconomyofconventionalvehicles.Alsoofferstheextendedrangeandrapidrefuellingthatconsumersexpectfromanormalvehicle,withalltheenergyandenvironmentalbenefitsofanelectricvehicle.Canbeusedinawiderangeofapplications,frompersonaltransportationtocommercialhauling.3HybridElectricVehicleCombinationofpetrolengineandelectricmotorEnergydensityPetrol-12,500Wh/kgLeadAcidbattery-25Wh/kgNickel-metalhydridebattery–44Wh/kgSerieshybrids:petrolenginedrivesalternatortostoreenergyinbatteriesorsenttoelectricmotorwhichpowersthewheels.Petrolengineneversuppliesthewheelsdirectly.4WhyHEV’s?

Hybridpowersystemsweredesignedasawaytocompensatefortheshortfallinbatterytechnology.Becausebatteriescouldsupplyonlyenoughenergyforshorttrips,anonboardgenerator,poweredbyaninternalcombustionengine,couldbeinstalledandusedforlongertrips.ThisistheconceptoftheHEV.Electricvehiclesareonlybeingusedinselectedmarketapplicationswherefewerkilometresaretravelled.Conventionalmotorvehiclespoweredbyinternal-combustionengines(ICE)posesubstantialeconomic,environmentalandenergysecurityissuesfortheplanet.5WhyHEV’s?

Moreefficientcarscanmakeabigdifferencetosocietyintermsofenvironmentalbenefits,andthestateoftheurbanairhasmotivatedbuyerstopurchasecleanercars.

UseofproductionHEVswillreducesmog-formingpollutantsoverthecurrentnationalaverage.6WhyHEV’s?

Hybridswillneverbetruezero-emissionvehicles,however,becauseoftheirinternalcombustionengine.Butthefirsthybridsonthemarketwillcutemissionsofglobal-warmingpollutantsbyathirdtoahalf,andlatermodelsmaycutemissionsbyevenmore.TheHondaInsight7HEVAdvantagesOneofthemostimportantdifferencesbetweenaHEVandanormalvehicleistheHEV'sabilitytoreclaimaportionoftheenergylosttobraking.InaHEV,whenthedriverbrakes,themotorbecomesagenerator,usingthekineticenergyofthevehicletogenerateelectricitythatcanbestoredinthebatteryforlateruse.Traditionalbrakesarenecessary,aswellasaconsistentstrategyforsmoothlyblendingthetwobrakingsystems.Regenerativeandfrictionbrakesneedtobecontrolledelectronicallysothatstoppingabilityismaximizedtomakethedualbrakeoperationnotnoticeabletothedriver.8HEVAdvantagesRegenerativebraking(explainedabove)capabilityhelpsminimizeenergylossandrecovertheenergyusedtoslowdownorstopavehicle.Enginescanbesizedtoaccommodateaverageload,notpeakload,whichreducestheengine'sweight.Fuelefficiencyisgreatlyincreased(hybridsconsumesignificantlylessfuelthanvehiclespoweredbygasolinealone).Emissionsaregreatlydecreased.HEVscanreducedependencyonfossilfuelsbecausetheycanrunonalternativefuels.SpeciallightweightmaterialsareusedtoreducetheoverallvehicleweightofHEVs.9TypesofHEV’s

ManyconfigurationsarepossibleforHEVs.Essentially,ahybridcombinesanenergystoragesystem,apowerunit,andavehiclepropulsionsystem.Theprimaryoptionsforenergystorageincludebatteries,ultracapacitors,andflywheels.Althoughbatteriesarebyfarthemostcommonenergystoragechoice,researchisstillbeingdoneinotherenergystorageareas.Hybridpowerunitoptionsaresparkignitionengines,compressionignitiondirectinjectionengines,gasturbines,andfuelcells.10PracticalrealisationsParallelhybrid:twopowerpathseitherengineormotor,orbothpowerthewheelsdirectly.SerieshybridismoreefficientbutparallelhybridhashigherpoweroutputneededinpracticalconditionsHondaInsightvsToyotaPriusInsightispureparallel;Priususescombinationofboth(enginepowersplitalongtwopaths–wheelsandalternatorwhichdrivestheelectricmotorandalsochargesthebatteries)11TypesofHEV’s

Propulsioncancomeentirelyfromanelectricmotor,suchasinainline(series)configuration,ortheenginemightprovidedirectmechanicalinputtothevehiclepropulsionsysteminaV(parallel)system.ThereareseveraltransmissionoptionswhenitcomestoHEVsaswell—thedriverdetermineswhichtransmissionwillbemostefficient.Ahybrid'sefficiencyandemissionsdependontheparticularcombinationofsubsystems,howthesesubsystemsareintegratedintoacompletesystem,andthecontrolstrategythatintegratesthesubsystems.Ahydrogenfuelcellhybrid,forexample,wouldproduceonlywaterasaby-productandrunatgreateroverallefficiencythanabattery-electricvehiclethatuseswall-plugelectricity.12HEVComponents

13HEVComponents

AHEVisanoptimisedmixofmanycomponents.Thevehicledrivetrainconsistsof:Electrictractionmotors/controllersElectricenergystoragesystems,suchasbatteries,ultracapacitors,andflywheelsHybridpowerunitssuchassparkignitionengines,compressionignitiondirectinjection(diesel)engines,gasturbines,andfuelcellsFuelsystemsforhybridpowerunitsTransmissions14HEVComponents

ThereareotherkeydevelopmentsbeingmadetohelpreduceemissionsandimprovetheefficiencyofHEVs:EmissioncontrolsystemsEnergymanagementandsystemscontrolThermalmanagementofcomponentsLight-weightandaerodynamicbody/chassisLowrollingresistance(includingtires)Reductionofaccessoryloadsinthevehicle15ThefutureofHEV’sHEVsarenowattheforefrontoftransportationtechnologydevelopment.Theyarereducingcriticalresourceconsumption,dependenceonforeignoil,airpollution,andtrafficcongestion.Theirwidespreadpenetrationintotheautomotivemarketdependsmainlyontheeconomicsofproducingacomplexhybridpowersystem,ratherthantheinherentcapabilitiesofthetechnologyitself.TheToyotaPrius16ThefutureofHEV’sAswithanynewtechnology,theremaybeobstructionstoitsacceptancebyconsumers,Buttimewillsoontell.TheHondaInsightisavailabletoUnitedStatesconsumersnow,andsofaritsbeengettingalotofattention.TheToyotaPriushasbeenavailableforsaleinJapansinceDecember1997andha