Page - 2 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 1217 notuseanystoredenergyorcauseanyemissionwhile idling, is capableof frequentstart-stopdriving, provides the total torque fromthestartup,anddoesnot require trips to thegasstation. Itdoesnot contributeeither toanyof thesmogmaking thecityairhighlypolluted. The instant torquemakes it highlypreferable formotor sports. Thequietness and low infrared signaturemakes it useful in militaryuseaswell. Thepowersector isgoingthroughachangingphasewhererenewablesourcesare gainingmomentum.Thenextgenerationpowergrid, called ‘smartgrid’ isalsobeingdeveloped. EVs arebeingconsideredamajorcontributor to thisnewpowersystemcomprisedofrenewablegenerating facilitiesandadvancedgridsystems[2,3].All thesehave ledtoarenewedinterestanddevelopment in thismodeof transport. The idea toemployelectricmotors todriveavehiclesurfacedafter the innovationof themotor itself. From1897to1900,EVsbecame28%of the totalvehiclesandwerepreferredover the internal combustionengine (ICE)ones [1]. But the ICEtypesgainedmomentumafterwards,andwithvery low oilprices, theysoonconqueredthemarket,becamemuchmorematureandadvanced,andEVsgot lost intooblivion.Achanceof resurrectionappeared in the formof theEV1concept fromGeneralMotors, whichwas launchedin1996,andquicklybecameverypopular.Other leadingcarmakers, including Ford,Toyota,andHondabroughtout theirownEVsaswell. Toyota’shighlysuccessfulPrius, thefirst commercialhybridelectricvehicle (HEV),was launched in Japan in1997,with18,000units sold in thefirstyearofproduction[1]. Today,almostnoneof those twentiethcenturyEVsexist; anexception canbeToyotaPrius, still goingstrong inabetterandevolvedform.Nowthemarket isdominated byNissanLeaf,ChevroletVolt, andTeslaModelS;whereas theChinesemarket is in thegripofBYD AutoCo.,Ltd. (X’anNationalHi-techIndustrialDevelopmentZone,Xi’an,China). EVscanbeconsideredasacombinationofdifferentsubsystems. Eachof thesesystemsinteract with each other tomake theEVwork, and there aremultiple technologies that can be employed tooperate thesubsystems. InFigure1,keypartsof these subsystemsandtheir contribution to the total systemisdemonstrated. Someof thesepartshavetoworkextensivelywithsomeof theothers, whereassomehaveto interactvery less.Whatever thecasemaybe, it is thecombinedworkofall these systemsthatmakeanEVoperate. Figure1.MajorEVsubsystemsandtheir interactions. Someof thesubsystemsareverycloselyrelated whilesomeothershavemoderated interactions.Data from[4]. 2