Page - 174 - in Emerging Technologies for Electric and Hybrid Vehicles

Energies 2017,10, 5 Secondly, inorder todemonstrate the improvementof theproposedbatterymodellingapproach duringthedynamicdrivingscenario, themodelandexperimentalvoltageoutputs in theconsecutive UDDSvalidation are plotted in Figure 15a, the corresponding calculated SoCprofile is shown in Figure15b,andthedetailedfigure from10,000s to12,000s isplotted inFigure15c. TheRMSEof the aforementionedestimationmethodsduringthewholeconsecutiveUDDStestarealsoshowninTable5. Figure15bshowsthat theconsecutiveUDDStest is startedfrom90%SoC, andterminatedwhenthe valueofSoCdropsbelow20%. It canbeobservedfromFigure15c thatparametersestimatedbythe improvedfittingfunctiongenerallydemonstrateabetterperformance,especiallyduringthedynamic period(rangingfrom10,000s to11,400s),becauseconsideringtheunsaturatedphenomenonof the long-termRCnetwork. It canalsobeconcludedthat themodelcontainingparametersestimatedby theprior1-hexperimentaldatafromtherestperiodgivesvoltageoutputwiththeleasterror,especially duringtheshort-timerestperiod. Inaddition, it canbeseenfromFigure5athat thereexistsarelatively long-timeandhighC-ratedischargingcurrent in theUDDScycleapproximatelyrangingfrom150s to 300s. Since larger timeconstantsareobtainedfromthedataof thewholerestperiod, thiscauses the correspondingvoltageoutputnot torecoverfastafterarelatively long-timedischargingcurrent,which leadstoanoffsetofvoltageerrors incomparisontothevoltageerrorcausedbytheproposedapproach. H[SHULPHQW FRQYHQWLRQDO LPSURYHG K LPSURYHG K 7LPH V (a) 7LPH V (b) Figure15.Cont. 174