EVS28 KINTEX, Korea, May 3-6, 2015 Power Rating of Hybrid Electric Vehicles for Vehicle Classification Dongseok Choi 1, Kihyeon Ryu, Jaewan Lee and Jaeseung Shin 1 Author 1 (corresponding author) TS Korea Automobile Testing and Research Institute, ( p g ) g, 200 Samjon-Ro, Songsan-Myun, Hwasung-Si, Gyeonggi-Do, 445-871, dsechoi@ts2020.kr
Introduction Current situation> - Mass production of HEVs and PHEVs for energy efficiency - Increased Electric Fraction of (P)HEVs for longer EV range - Clear demand from WLTP-SG-EV (P-to-M ratio, Downscaling Method, Gear Shift Model) Problems> - Representative power for HEVs and PHEVs - Vehicle classification and Taxation (vehicle occupation tax) - Not defined terminology on (P)HEV s power Suggested solution> - Concept of system power 2
Motivation Concept of system power What is the system power? The power is measured at the end side of the powertrain without tires. The power obtained the relationship between wheel torque and vehicle speed. Energy Storage Powertrain Energy Converter (ICE, E-Motor, Fuel cell, ) Drivetrain Wheel torque Wheel torque < Defined by UN/WP.29/GRPE/ VPSD IWG > 3
Objective ICE power E-Motor power HEVs System power ICE E-Motor P, T P T P, T T P P, T Vehicle P T N N V P : power T : torque N : speed V : vehicle speed 4
Background Related standards SAE J1491 : Vehicle Acceleration Measurement (2006) - Measuring launch response and acceleration performance - Passenger cars and light-duty trucks - Field test procedure - Uncertainty about test result -- Effect of ambient conditions on tire pressure and temperature -- Track coefficient of static and dynamic friction -- Non standard instrumentation -- Driver difference -- Track temperature SAE J2908 : HEV System Power Ratings (on going) - Powertrain power rating (Wheel torque and Power) - Electric assist - Electric-only power rating - Regen power rating 5
Powertrain test bed Test bed Dynamometer spec. Max power : 290 kw @1100 ~ 3000 rpm Max torque : 2500 Nm @ ~ 1100 rpm (40% overload : 3500 Nm) Wheel base : 1.8 ~ 3.8 m Thread : 1.2 ~ 2.2 m Control jig for accelerator pedal 6
Test vehicles Specification of powertrain for test vehicles Power Items Drivetrain Electric Fraction Test Type (EF) ICE E-Motor Vehicles [%] [kw] [kw] HEV 1 133.2 15 AT(6) 10.1 HEV 2 110.4 30 AT(6) 21.4 HEV 3 72.9 60.4 e-cvt 45.3 PHEV 72.9 60.4 e-cvt 45.3 HEV 4 116.3 105.2 e-cvt 47.5 EF = Motor power (ICE power + Motor power) X 100 7
Development process V min x, V max Vhil Vehicle warming Test cyclecle Da ssing ta proces 8
Test procedure and test method @ 90 ± 10 km/h for 20min RL adapted = RL track F powertrain loss @ 90 ± 10 km/h for 10min 9
Determination of max system power How to determine max system power? : 5% error bar Criterion for max power : < COV 2% 10
Test result of HEV 1 (EF = 10.1%) Belt Motor (15 kw) ICE (133.2 kw) AT Wheel Max. power : 103.4 kw Test No. Max M.S.P Vehicle V.S. System difference Speed difference Power (kw) (%) (km/h) (%) 1 103.4-0.4 139 0.5 2 103.0-0.8 137-1.0 3 105.0 1.2 139 0.5 Avg. 103.8-138 - 11
Test result of HEV 2 (EF = 21.4%) ICE (110.4kW) Motor(30kW) AT Wheel Max. power : 103.2kW Test No. Max M.S.P Vehicle V.S. System difference Speed difference Power (kw) (%) (km/h) (%) 1 102.4-0.4 147 0.7 2 102.7-0.1 146 0.0 3 103.2 0.4 145-0.7 Avg. 102.8-146 - 12
Test result of HEV 3 (EF = 45.3%) ICE (72.9 kw) Motor (60.4 kw) e-cvt Wheel Max. power : 74.4kW Test No. Max M.S.P Vehicle V.S. System difference Speed difference Power (kw) (%) (km/h) (%) 1 74.1-0.1 139 0.2 2 74.1-0.1 137-1.2 3 74.4 0.3 140 1.0 Avg. 74.2-139 - 13
Test result of PHEV (EF = 45.3%) ICE (72.9 kw) Motor (60.4 kw) e-cvt Wheel Max. power : 78.9kW Test No. Max M.S.P Vehicle V.S. System difference Speed difference Power (kw) (%) (km/h) (%) 1 78.9 0.3 150-1.7 2 78.5-0.2 156 2.2 3 78.6-0.1 152-0.4 Avg. 78.7-153 - 14
Test result of HEV 4 (EF = 47.5%) ICE (116.3 kw) Motor (105.2 kw) e-cvt Wheel Max. power : 119.7kW Test No. Max M.S.P Vehicle V.S. System difference Speed difference Power (kw) (%) (km/h) (%) 1 119.7 0.6 117 2.0 2 115.6-2.9 113-1.5 3 121.8 2.3 114-0.6 Avg. 119.0-115 - 15
Conclusions and future work Conclusions System power means the power is measured at the end side of the powertrain without a tire. For the determination of max system power, the criterion was the less than COV 2%. The test procedure for system power measurement was developed and the test result had a good repeatability within ±3 percent. Future work To validate the test procedure for various types of vehicles such as plug-in hybrid vehicles and electric vehicles with in-wheel motors 16
Acknowledgements This research was supported by the Ministry of Land, Infrastructure and Transport. It was also supported by the Korea Agency for Infrastructure Technology Advancement (Project No. : 13PTSI-C054118-05). htt // http://www.car.go.kr k 17