Page - 165 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 5 7LPH V 6R& 6R& 6R& 6R& 6R& 6R& 7LPH V 6R& 6R& 6R& 6R& 6R& 6R& (a) (b) Figure4. (a) TheprofilesofVP atdifferentSoC intervalsduring thepulse-chargingperiod; (b) the profilesof|VP|atdifferentSoCpointsduringtherestperiod. Consequently, it canbeconcludedthat thevoltageresponseduringthepulse-chargingperiodcan betterdescribe thecharacteristicof theCCchargingprocessbecauseof thesimilarcurrentexcitation. 3.2. RCNetworkParameters for theDynamicDrivingScenario 3.2.1. TypicalDynamicDrivingScenarios For thedynamicdrivingscenario,especially for theurbandrivingscenario,vehiclesaccelerate andbrake frequently,whichcause the long lasting loadcurrent toseldomexist. Thereare twotypical kindsof standardurbandrivingcycles, namely theurbandynamometerdrivingschedule (UDDS) andtheworldwideharmonized lightvehicles testprocedure (WLTP),whichare theAmericanand Europeancertificationcycles, respectively. The loadcurrentprofilesandthe loadcurrentamplitude distributionsof the twodrivingcyclesareplotted inFigure5. It canbeobservedfromFigure5a,b that bothof thedynamiccurrentprofilesvary frequentlyover the test span.Meanwhile, fromFigure5c,d, it canbeconcludedthat: (1) thedischargingcurrentaccounts foramuch largerportion, compared to thechargingcurrentduringtheregenerativeprocess; (2)amongthe loadcurrents, the lowC-rate dischargingcurrent,particularlyaroundzero-valueamplitudes,accounts fora largerportion inboth tests.Hence, thevoltageresponseduring therestperiodcanbeemployedtoestimate theRCnetwork parameters for thedynamicdrivingscenario. 165