Page - 4 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 1217 butnone iscomparable to the little timerequiredtorefilla fuel tank.Chargingtimedependsonthe charger configuration, its infrastructure andoperatingpower level. AdvantagesofBEVsare their simpleconstruction,operationandconvenience. Thesedonotproduceanygreenhousegas (GHG), donot create anynoise and therefore beneficial to the environment. Electric propulsionprovides instant andhigh torques, even at lowspeeds. These advantages, coupledwith their limitationof range,makes themtheperfectvehicle touse inurbanareas; asdepicted inFigure2,urbandriving requires runningatslowormediumspeeds,andtheserangesdemandalotof torque.NissanLeafand Teslasaresomehigh-sellingBEVsthesedays,alongwithsomeChinesevehicles. Figure3showsbasic configurationforBEVs: thewheelsaredrivenbyelectricmotor(s)which is runbybatteries througha powerconvertercircuit. Figure2.FederalUrbanDrivingSchedule torque-speedrequirements.Mostof thedriving isdone in the2200 to4800rpmrangewithsignificantamountof torque. Lowerrpmsrequire torquesashighas 125Nm;urbanvehicleshave tooperate in this regionregularlyas theyface frequentstart-stops.Data from[4]. Figure3.BEVconfiguration. Thebattery’sDCpower is converted toACbythe inverter to run the motor.Adaptedfrom[5]. 2.2.HybridElectricVehicle (HEV) HEVsemploybothanICEandanelectricalpower train topower thevehicle. Thecombinationof these twocancomeindifferent formswhicharediscussed later.AnHEVuses theelectricpropulsion systemwhenthepowerdemandis low. It isagreatadvantageinlowspeedconditionslikeurbanareas; 4