-
Chalmers University of Technology
Speed (rpm)
0 5000 10000
EM
Tor
que
(Nm
)
0
50
100
908050
9496
908050
94
Speed (rpm)
0 5000 10000
EM
Tor
que
(Nm
)0
50
100
98
9480
98
98
9480
98
SOC (%)0 20 40 60 80 100
Vol
tage
(V)
200
250
300
350
400
450
329 V
401 V
412 V
245 V
Voc
Vt @ P max
Vt, max
Vt, min
Time (s)0 500 1000 1500 2000
Spee
d (k
m/h
)
0
50
100
150
Speed (rpm)
2000 6000 10000
Torq
ue (N
m)
0
50
100
150
508090
95
98
• Wh• Wh/km• SOC(%)
Electric Drive system Scaling - Influence on Acceleration, Energy Use and Cost
Department of Energy and Environment
Emma Arfa GrunditzDivision of Electric Power Engineering
Investigates the consequence ono Performanceo energy consumptiono costwhile scaling the electric drive system 50%-200% of a Small and Large electric car.
Purpose
Conclusions
Results• Drive cycle energy consumption per distance (Wh/km)
o Low speedo Middle speedo High speed
• Acceleration time (s)o 0-50 km/ho 0-100 km/h
Method & Modelling• Axial scaling of the active length of
the permanent magnet motor…• … and rewinding to keep base speed• Scalable inverter module model• Vehicle Simulink model with load
dependent models
• Lowest Wh/km: 96% for Small car, 97% for Large Car • Down-scaling to 70% is possible and still manage all drive cycles • Then 0-100 increase 2 s• The cost decrease 10% for Small system and 15% for Large
M
Inverter
Battery
Electricmachine
VDC
Singlespeedgear
Driving wheel pair
Differential
200%50%
Cost estimation• Motor subparts
o Core laminationo Windingo Magnets (NdFeB)o Housingo Frame
• Inverter subpartso Power moduleo DC-Link capacitoro Driver and Controller cardso Busbarso Housing
Speed
Torq
ue
200%
50%
EM scaling (%)50 100 150 200
Nor
m. E
batt
ery
(%)
94
96
98
100
102
104
106
108
110
112ECEWLTC Low
jc08FTP72 (UDDS)WLTC MdlSC03NYCCArtemis URBANNEDC
WLTC HghArtemis RURALEUDCWLTCLA92 (UC)HWFETREP05
WLTC ExtrHghUS06ArtemisMW130
Small
EM scaling (%)50 100 150 200
Nor
m. E
batt
ery
(%)
96
98
100
102
104
106
108
110
112 ECEWLTC Low
jc08FTP72 (UDDS)WLTC MdlSC03NYCCArtemis URBANNEDC
WLTC HghArtemis RURALEUDCWLTCLA92 (UC)HWFETREP05
WLTC ExtrHghUS06ArtemisMW130
Large
0 100 200 300 400 5000
5
10
15
20
25
30
Tim
e (s
)
Max. EM Torque (Nm)
Small - 0-100km/hSmall - 0-50km/hLarge - 0-100km/hLarge 0-50km/h
1214
1618
21
111213
1518
21
Electric Drive system Scaling - Influence on Acceleration, Energy Use and Cost
