Embed Size (px)
Citation preview
1© Ricardo plc 2009RD.09/17905.3
FD807 Electric Vehicle Component Sizing
vs. Vehicle Structural Weight Report
Research Report
Conducted by Ricardo
for The Aluminum Association
2009 - 10
2© Ricardo plc 2009RD.09/17905.3
Scope of Work
This report was generated at the request of the Aluminum Association. The purpose of
this study is to evaluate the impact of vehicle structural weight reduction on Electric
Vehicle powertrain component size for various operating range targets.
Ricardo used previous data from the vehicle weight reduction study on fuel economy for
light duty vehicles [FB769] to modify the small car and SUV models for EV operation. The
FTP75 cycle was used to size the initial electric powertrain to achieve a 40 and 80 miles
range. Also reported in this report is the range based on the HWFET cycle and 45 / 70
mph steady state operation. The baseline EV performance [0-30 mph, 0-60 mph] were
kept comparable to the initial conventional vehicle.
For each iteration, the electrical powertrain weight was computed and deducted from the
original conventional powertrain. The vehicle structural weight was updated based the
new powertrain mass and size based on the Aluminum Association’s structural weight
computation. The electrical powertrain was then re-sized iteratively to keep range constant
at similar performance.
3© Ricardo plc 2009RD.09/17905.3
Content
This report consists of the following sections:
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
4© Ricardo plc 2009RD.09/17905.3
Conventional Powertrain Masses
The original conventional powertrain masses for the two vehicles were estimated in the table below.
The new EV powertrain masses will be estimated and compared for both vehicles. They do not
include the fuel tank and battery.
5© Ricardo plc 2009RD.09/17905.3
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
Content
6© Ricardo plc 2009RD.09/17905.3
EV Modeling General Assumptions
The EV vehicle was modeled and performance was measured using the following assumptions:
The base EV rolling resistance coefficient and aero coefficient were unchanged from the
baseline conventional numbers
The EV powertrain is simplified to only use 1 fixed final drive ratio
The number reported in this report for battery capacity represent the total capacity as opposed
to usable capacity unless noted otherwise
The usable SOC range was limited to a 0.9 to 0.25 range
No thermal system simulation was performed
The battery sizing was solely based on the FTP75 cycle results
The motor sizing was based on the FTP75, 0-60 mph acceleration and top speed
No additional performance for sizing was used in the analysis
No additional load were added to the battery other than the propulsion motor request
Motor was assumed to be capable of sustaining acceleration performance and top speed
within the simulated transient time
7© Ricardo plc 2009RD.09/17905.3
EV Models – Model Conversion from FB769
Conventional Small Vehicle Small Electric Vehicle
Battery Model
Control Module
Motor/Generator
model
Final Drive
Vehicle
Model
Driver
Model
Data Transferred
The following vehicle parameters were kept unchanged in the conversion from the Conventional
Powertrain from the previous study to the new Electrical Powertrain. The EV powertrain was modeled
using Ricardo EASY5 Powertrain Library.
Note: the constant portion of the rolling resistance is dependant on vehicle mass and hence will vary as vehicle mass is updated.
* Cd = aero coefficient, A = frontal area
* m2
8© Ricardo plc 2009RD.09/17905.3
Basic Modeling Inputs Description
The electric powertrain is populated with the following data :
Battery [Lithium Ion]
Open Circuit Voltage: 360 V
SOC range [usable]: 0.9 - 0.25
Usable energy to mass of pack: approx.115 W-h/kg
Usable energy to volume of pack: approx.155 W-h/L
Price for Total energy: $750/kWh as provided by the Aluminum Association
Electric Motor / Generator
Performance and Efficiency scaled based on UQM 125 kW motor,300 N.m machine
Motor and Generator Efficiency plotted on the right
Max Speed maintained at 8000 rpm
Power Density: approx. 3.05 kW/kg kept constant
Motor Controller
Control Electric Motor based on driver vehicle speed demand
95% Efficiency in Power Conversion
Regen-braking threshold set at 1000N braking, when throttle = 0
Mass approximated to 14 kg.
Fixed Final Drive
Sized for both vehicles, 98% efficiency
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
6
0.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92 0
.92
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
250
300
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.66
0.6
60.6
6
0.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.720.72
0.7
20.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
20.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.92
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
20
40
60
80
100
120
Motor Characteristics
Generator Characteristics
9© Ricardo plc 2009RD.09/17905.3
EV Models – Electrical Powertrain Modeling and Assumptions
The small car and SUV electric powertrain components [battery and motor size, final ratio] are sized in order to achieve the following vehicle performance:
Ranges:
40 miles
80 miles
Acceleration:
0-60 mph: similar to baseline conventional vehicles [within 1-2s]
Top Speed:
Around 90-110 mph [similar to published Volt, BMW Mini EV information]
As the vehicle weight will be modified, vehicle weight effect and its interactions with the rest of the electrical components is studied via Design of Experiments. The DoE design variables are:
Battery size: 10 – 40 kWh [usable energy]
Motor / Generator size [linear scaling of the torque axis in efficiency maps]: 80 – 150 kW
Final Drive Ratio: 4:1 – 8:1
Vehicle Weight Reduction: 0 – 700 kg
Max Torque Speed range [40% to 70% of motor speed range]
Data Columns BatterykWh MotorkW FDR
Scatterplot 3D
10© Ricardo plc 2009RD.09/17905.3
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
Content
11© Ricardo plc 2009RD.09/17905.3
Small Car EV Base Model Design [40 & 80 miles range]
The base Mini EV set up is based on FTP results for range, acceleration performance and top speed [limit 100mph].
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
6
0.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92 0
.92
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
100 mph
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.660.660.66
0.6
6
0.680.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.7
0.720.720.72
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
2
0.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.9
2
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
20
40
60
80
100
Conventional Vehicle
0-60 mph = 10.3s
Brake Regen accounts for 19.3%
of the achieved range
FTP motor operating
points [10Hz]
FTP generator operating
points [10Hz]11
Mass Constant @ 1304 kg
12© Ricardo plc 2009RD.09/17905.3
Small Car EV Base Model Operation
HWFET range is 39.4 miles with the 14.6 kWh [total] battery, and 77.5 mi with the 28.7 kWh [total] battery. Lower brake
regen is available on the HWFET.
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
6
0.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.740.7
4
0.7
4
0.760.760.7
6
0.7
6
0.780.780.7
8
0.7
8
0.80.80.8
0.8
0.820.820.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.860.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92 0
.92
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
Top Speed
100 mph
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.660.660.66
0.6
6
0.680.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.7
0.720.720.72
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
60.78
0.780.7
80.7
80.8
0.80.8
0.8
0.82
0.82
0.8
2
0.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.9
2
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
20
40
60
80
100
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
6
0.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92 0
.92
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.66
0.6
60.6
6
0.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.720.72
0.7
20.7
2
0.740.74
0.7
40.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
2
0.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.92
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
20
40
60
80
100
HWFET Operating Points FTP and Top Speed Operating Points
Brake Regen accounts for 4%
of the achieved range
Brake Regen accounts for 19.3%
of the achieved range
13© Ricardo plc 2009RD.09/17905.3
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
Content
14© Ricardo plc 2009RD.09/17905.3
HorizVert
BatterykWh
MotorkW
FDR
WeightReductionkg
RatedSpeedFactor
Factor
41.421811
92.703016
700
0
0.4
Current X
Range Formula
MotorEf f Formula
RMS Formula
0-30 time [s] Formula
0-60 time [s] Formula
Top Speed [mph] Formula
Response
40
0.705
91
13.75
12
102.5
Contour
134.4783
0.7573263
94.341806
5.1775784
11.918718
108.59275
Current Y
.
.
.
.
.
.
Lo Limit
.
.
.
.
.
.
Hi Limit
80
90
100
110
120
130
140
150
Moto
rkW
Range Formula
0-60 ti me [s ] Form ul a
Top Speed [mph] Formula
40 60 80 100 12014014
13
12
11
10
9
8
7
110
120
130
10 15 20 25 30 35 40 45
BatterykWh
0BatterykWh
MotorkW
Range Formula
0BatterykWh
MotorkW
MotorEff Formula
0BatterykWh
MotorkW
RMS Formula
0BatterykWh
MotorkW
0-30 ti me [s ] Form ul a
0BatterykWh
MotorkW
0-60 ti me [s ] Form ul a
0BatterykWh
MotorkW
Top Speed [mph] Formula
Contour Profiler
100 mph top speed line
85 mph top speed line
40
mi ra
ng
e [
FT
P]
80
mi ra
ng
e [
FT
P]
10s time on 0-60 mph
9s time on 0-60 mph
Mass Constant @ 1928 kg
Small SUV EV Base Model Design [40 & 80 miles range]
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
60.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92
0.9
2
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
250
300
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.66
0.6
60.6
6
0.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.720.72
0.7
20.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
20.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.92
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]P
ow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
10
20
30
40
50
60
70
80
90
100
Top Speed
91 mph
The base small SUV EV set up is based on FTP results for range, acceleration performance
and top speed [limit 90mph]. Higher FDR were needed to meet 0-60 mph acceleration
[10s vs. 9.3s conventional].
130 mph top speed line
Brake Regen accounts for 21.4%
of the achieved range
15© Ricardo plc 2009RD.09/17905.3
Small EV Base Model Operation
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
60.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92
0.9
2
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
250
300
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.66
0.6
60.6
6
0.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.720.72
0.7
20.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
20.8
2
0.84
0.84
0.8
40.8
4
0.86
0.86
0.8
6
0.8
6
0.88
0.88
0.88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.92
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
10
20
30
40
50
60
70
80
90
100
0.580.58 0.60.6 0.620.62
0.6
2
0.6
2
0.640.64
0.6
4
0.6
4
0.660.66
0.6
60.6
6
0.680.68
0.6
8
0.6
8
0.70.7
0.7
0.7
0.720.72
0.7
2
0.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
6
0.7
6
0.780.78
0.7
8
0.7
8
0.80.8
0.8
0.8
0.820.82
0.8
2
0.8
2
0.840.84
0.8
4
0.8
4
0.860.86
0.8
6
0.8
6
0.880.88
0.8
8
0.8
8
0.90.9
0.9
0.9
0.92
0.9
2
0.92
0.92
0.9
4
Motor Speed [RPM]
Moto
r T
orq
ue [
N.m
]
Operating Points [Motoring]
0 1000 2000 3000 4000 5000 6000 7000 80000
50
100
150
200
250
300
0.540.54 0.560.56 0.580.58 0.60.6
0.620.62
0.640.64
0.66
0.6
60.6
6
0.680.68
0.6
80.6
8
0.70.7
0.7
0.7
0.720.72
0.7
20.7
2
0.740.74
0.7
4
0.7
4
0.760.76
0.7
60.7
6
0.780.78
0.7
80.7
8
0.80.8
0.8
0.8
0.82
0.82
0.8
20.8
2
0.84
0.84
0.8
40.8
40.86
0.86
0.8
6
0.8
6
0.88
0.880.
88
0.8
8
0.9
0.9
0.9
0.9
0.9
2
0.92
0.92
0.9
2
0.9
2
0.9
4
Generator Speed [RPM]
Pow
er
[kW
]
Operating Points [Generator]
0 1000 2000 3000 4000 5000 6000 7000 80000
10
20
30
40
50
60
70
80
90
100
HWFET Operating PointsFTP Operating Points
Brake Regen accounts for 21.4%
of the achieved range Brake Regen accounts for 4%
of the achieved range
Top Speed
91 mph
HWFET range is also 37.5 miles with the 19.5 kWh [total] battery, and 73.5 mi with the 38.3 kWh [total] battery.
16© Ricardo plc 2009RD.09/17905.3
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
Content
17© Ricardo plc 2009RD.09/17905.3
Weight Iterations Cases
The Aluminum Association provided the new vehicle weights for 4 architecture cases. The new weights were plugged in the model and the battery was resized in order to keep the EVs’ range to 40 and 80 miles. Two iterations were performed in order to match the EV powertrain mass to the new vehicle mass. Battery rating and cost difference with the initial conventional vehicle weight is computed. The EV powertrain was also re-sized to further optimize for efficiency.
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure– Use Base Vehicle Steel Structure
– Partially removed the conventional powertrain weight to represent a Extended EV / Series Hybrid *
– Added EV Powertrain Weight
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure– Use Aluminum Structure
– Partially removed the powertrain weight to represent a Extended EV / Series Hybrid *
– Added EV Powertrain Weight
Case 3: Weight Represent a Full EV Configuration with Steel Structure– Use Steel Structure
– Removed the entire baseline conventional powertrain weight
– Added EV Powertrain Weight
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure– Use Aluminum Structure
– Removed the entire base baseline conventional powertrain weight
– Added EV Powertrain Weight
* Note: All performance runs are in full EV mode only.
18© Ricardo plc 2009RD.09/17905.3
Un-optimized Weight Iterations Results – Small Car
Two iterations are necessary to match the vehicle weight to the EV powertrain weight. The Aluminum
structure provided the opportunity to reduce battery cost by about $5,600. Further optimization is
necessary in order to match the motor rating to the new vehicle weight with a potential secondary effect on
downsizing the battery.
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure
Case 3: Weight Represent a Full EV Configuration with Steel Structure
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure
2
19© Ricardo plc 2009RD.09/17905.3
Un-optimized Weight Iterations Results – Small SUV
Two iterations are necessary to match the vehicle weight to the EV powertrain weight. The Aluminum
structure provided the opportunity to reduce battery cost by about $6,500. Further optimization is
necessary in order to match the motor rating to the new vehicle weight with a potential secondary effect on
downsizing the battery.
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure
Case 3: Weight Represent a Full EV Configuration with Steel Structure
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure
2
20© Ricardo plc 2009RD.09/17905.3
Powertrain Optimization
Response Surface Models [RSM]
are created for:
FTP Range [design target]
HWFET Range
Steady State at 45 and 70 mph
Acceleration: 0-30 & 0-60 mph
Top Speed
The RSM R2 are around 0.99, hence
the models are accurate to optimize
for range while constraining for
acceleration and top speed. Once
the design variables are set using
the RSM, the model is run to check
for the performance.
The table on the right shows the
prediction profile for the small car,
Case 4 [40 mi range].
All the RSM plots for each cases are
in Appendix A.
10
40
70
100
130
FT
P R
ange
Form
ula
40.1
8272
10
30
60
80
110
Range H
WF
ET
Form
ula
32.9
5398
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
5.0
23485
10
20
0-6
0 T
ime
Form
ula
9.9
36813
50
70
90
110
130
Top S
peed
mph F
orm
ula
102.9
036
10
40
70
100
130
45 m
ph R
ange
Form
ula
37.2
6913
10
30
50
70
70 m
ph R
ange
Form
ula
21.6
8829
10
20
5.9
BatterykWh
70
80
90
100
110
70
MotorkW
400
500
600
700
800
519.9
FDR
0
100
200
300
500
600
700
641.5
WeightReductionkg
0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.7
RatedSpeedFactor
Prediction Profiler
Profiler
21© Ricardo plc 2009RD.09/17905.3
Small Car Results
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure
Case 3: Weight Represent a Full EV Configuration with Steel Structure
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure
See Appendix A for plots
2
22© Ricardo plc 2009RD.09/17905.3
Small Car Results – Energy Usage
Case 1: 1205 kg[Regen = 20.9%]
Case 2: 1031 kg[Regen = 20%]
Case 3: 781 kg[Regen = 18.1%]
Case 4: 627 kg[Regen = 15.6%]
23© Ricardo plc 2009RD.09/17905.3
Small Car Results – Pareto Plots [Range]
Based on a quadratic regression analysis order, the pareto plots show that the main effects for vehicle
range improvement are driven by the battery size, vehicle weight reduction and the interaction between
battery size and weight reduction. The FTP range is also more sensitive to the vehicle weight than the
other cycle. FDR trends are negative but acceleration time would be inversely affected – multi-ratio
transmission would enable optimization of the range on a wider range of operation.
Note: The plot represents the effect of the design variables on
range while unconstrained by vehicle acceleration performance
24© Ricardo plc 2009RD.09/17905.3
Small SUV Results
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure
Case 3: Weight Represent a Full EV Configuration with Steel Structure
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure
See Appendix A for plots
2
25© Ricardo plc 2009RD.09/17905.3
Small SUV Results – Energy Usage
Case 1: 1719 kg[Regen = 22.7%]
Case 2: 1460 kg[Regen = 21.4%]
Case 3: 1132 kg[Regen = 18.3%]
Case 4: 927 kg[Regen = 15.6%]
Case 1: Weight Represent a Series Hybrid / Extended EV Configuration with Steel Structure
Case 2: Weight Represent a Series Hybrid / Extended EV Configuration with Aluminum Structure
Case 3: Weight Represent a Full EV Configuration with Steel Structure
Case 4: Weight Represent a Full EV Configuration with Aluminum Structure
26© Ricardo plc 2009RD.09/17905.3
Small SUV Results – Pareto Plots [Range]
Based on a quadratic regression analysis order, the pareto plots show that the main variables for vehicle
range improvement are the battery size, vehicle weight reduction and the interaction between battery size
and weight reduction. The FDR effect on the FTP is different than for the other cycles – hence an
optimized system for a wide range of operation would need more than 1 fixed ratio. The FTP sensitivity to
battery size is lower than the other cycles thanks to higher braking regeneration.
Note: The plot represents the effect of the design variables on
range while unconstrained by vehicle acceleration performance
27© Ricardo plc 2009RD.09/17905.3
Conventional powertrain mass estimates
EV Modeling and Assumptions
Small Car EV sizing results
Small Car design space evaluation
FTP and HWFET Results
Small SUV EV sizing Results
Small SUV design space evaluation
FTP and HWFET Results
Weight Iterations and further optimization
Conclusion.
Content
28© Ricardo plc 2009RD.09/17905.3
APPENDIX A –
RESPONSE SURFACE PREDICTIONS
PLOTS
29© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 1 [40 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
40.5
4453
10
30
60
80
110
Range H
WF
ET
Form
ula
37.3
1152
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.9
00769
10
20
0-6
0 T
ime
Form
ula
9.9
79422
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.1
949
10
40
70
100
130
45 m
ph R
ange
Form
ula
41.3
5998
10
30
50
70
70 m
ph R
ange
Form
ula
27.9
8062
10
20
8.7
BatterykWh
70
80
90
100
110
101.04
MotorkW
400
500
600
700
800
537.1
FDR
0
100
200
300
400
500
600
700
79.2
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.5837
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
30© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 2 [40 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
39.9
1969
10
30
60
80
110
Range H
WF
ET
Form
ula
36.1
4653
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.9
49335
10
20
0-6
0 T
ime
Form
ula
10.1
0303
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.4
789
10
40
70
100
130
45 m
ph R
ange
Form
ula
40.6
1051
10
30
50
70
70 m
ph R
ange
Form
ula
26.2
7386
10
20
7.88
BatterykWh
70
80
90
100
110
88.08
MotorkW
400
500
600
700
800
535.5
FDR
0
100
200
300
400
500
600
700
247.7
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.5837
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
31© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 3 [40 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
40.6
3395
10
30
60
80
110
Range H
WF
ET
Form
ula
35.0
2468
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.7
5367
10
20
0-6
0 T
ime
Form
ula
10.0
0644
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.1
156
10
40
70
100
130
45 m
ph R
ange
Form
ula
39.3
9013
10
30
50
70
70 m
ph R
ange
Form
ula
23.9
7209
10
20
6.77
BatterykWh
70
80
90
100
110
73.08
MotorkW
400
500
600
700
800
535.5
FDR
0
100
200
300
400
500
600
700
489.5
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.611
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
32© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 4 [40 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
40.5
3589
10
30
60
80
110
Range H
WF
ET
Form
ula
32.9
4017
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.8
44657
10
20
0-6
0 T
ime
Form
ula
9.5
89029
50
70
90
110
130
Top S
peed
mph F
orm
ula
99.7
3798
10
40
70
100
130
45 m
ph R
ange
Form
ula
36.9
2874
10
30
50
70
70 m
ph R
ange
Form
ula
21.7
946
10
20
5.93
BatterykWh
70
80
90
100
110
70
MotorkW
400
500
600
700
800
535.5
FDR
0
100
200
300
400
500
600
700
644.6
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.7
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
33© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 1 [80 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
79.5
0043
10
30
60
80
110
Range H
WF
ET
Form
ula
75.7
3133
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.8
43012
10
20
0-6
0 T
ime
Form
ula
9.9
66395
50
70
90
110
130
Top S
peed
mph F
orm
ula
101.1
807
10
40
70
100
130
45 m
ph R
ange
Form
ula
82.1
3254
10
30
50
70
70 m
ph R
ange
Form
ula
57.4
9835
10
20
18.35
BatterykWh
70
80
90
100
110
107.27
MotorkW
400
500
600
700
800
532
FDR
0
100
200
300
400
500
600
700
0
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.5812
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
34© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 2 [80 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
79.8
8444
10
30
60
80
110
Range H
WF
ET
Form
ula
73.8
7733
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.9
93579
10
20
0-6
0 T
ime
Form
ula
10.1
2485
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.5
438
10
40
70
100
130
45 m
ph R
ange
Form
ula
80.9
9948
10
30
50
70
70 m
ph R
ange
Form
ula
54.4
2493
10
20
16.53
BatterykWh
70
80
90
100
110
92.97
MotorkW
400
500
600
700
800
535.5
FDR
0
100
200
300
400
500
600
700
173.3
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.5812
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
35© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 3 [80 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
80.0
3113
10
30
60
80
110
Range H
WF
ET
Form
ula
69.6
6615
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.8
11465
10
20
0-6
0 T
ime
Form
ula
10.0
155
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.1
815
10
40
70
100
130
45 m
ph R
ange
Form
ula
77.0
787
10
30
50
70
70 m
ph R
ange
Form
ula
49.1
2826
10
20
13.99
BatterykWh
70
80
90
100
110
80.06
MotorkW
400
500
600
700
800
535.5
FDR
0
100
200
300
400
500
600
700
427.5
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.6219
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
36© Ricardo plc 2009RD.09/17905.3
Appendix A: Small Car – Case 4 [80 mi]
10
40
70
100
130
FT
P R
ange
Form
ula
80.2
4554
10
30
60
80
110
Range H
WF
ET
Form
ula
67.0
4866
3
5
7
9
11
13
0-3
0 T
ime
Form
ula
4.1
8504
10
20
0-6
0 T
ime
Form
ula
8.8
42494
50
70
90
110
130
Top S
peed
mph F
orm
ula
100.7
692
10
40
70
100
130
45 m
ph R
ange
Form
ula
74.6
2429
10
30
50
70
70 m
ph R
ange
Form
ula
45.7
035
10
20
12.42
BatterykWh
70
80
90
100
110
70
MotorkW
400
500
600
700
800
530.8
FDR
0
100
200
300
400
500
600
700
583.8
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.5823
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
37© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 1 [40 mi]
10
40
70
100
130
Range F
TP
Form
ula
40.0
1647
10
30
50
70
90
Range H
WF
ET
Form
ula
35.3
1922
10
20
0-3
0 T
ime
Form
ula
4.4
56241
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
22228
60
80
100
120
Top S
peed
mph F
orm
ula
90.9
8975
10
30
60
80
110
Range 4
5
mph F
orm
ula
39.7
5432
10
30
50
Range 7
0
mph F
orm
ula
24.2
5879
10
20
11.24
BatterykWh
70
80
90
100
110
96.21
MotorkW
400
500
600
700
800
700.9
FDR
-100
100
300
500
700
900
1100
107
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
38© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 2 [40 mi]
10
40
70
100
130
Range F
TP
Form
ula
39.9
5707
10
30
50
70
90
Range H
WF
ET
Form
ula
34.4
3219
10
20
0-3
0 T
ime
Form
ula
4.4
50365
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
98216
60
80
100
120
Top S
peed
mph F
orm
ula
90.8
4806
10
30
60
80
110
Range 4
5
mph F
orm
ula
39.4
0747
10
30
50
Range 7
0
mph F
orm
ula
23.3
7016
10
20
10.44
BatterykWh
70
80
90
100
110
84.02
MotorkW
400
500
600
700
800
700.9
FDR
-100
100
300
500
700
900
1100
359
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
39© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 3 [40 mi]
10
40
70
100
130
Range F
TP
Form
ula
40.2
0586
10
30
50
70
90
Range H
WF
ET
Form
ula
33.1
0242
10
20
0-3
0 T
ime
Form
ula
4.4
31501
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
26402
60
80
100
120
Top S
peed
mph F
orm
ula
97.5
5348
10
30
60
80
110
Range 4
5
mph F
orm
ula
38.8
3725
10
30
50
Range 7
0
mph F
orm
ula
21.9
6697
10
20
9.3
BatterykWh
70
80
90
100
110
71.37
MotorkW
400
500
600
700
800
645.7
FDR
-100
100
300
500
700
900
1100
678
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
40© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 4 [40 mi]
10
40
70
100
130
Range F
TP
Form
ula
40.2
5211
10
30
50
70
90R
ange H
WF
ET
Form
ula
31.6
736
10
20
0-3
0 T
ime
Form
ula
4.5
60895
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
8529
60
80
100
120
Top S
peed
mph F
orm
ula
101.3
98
10
30
60
80
110
Range 4
5
mph F
orm
ula
37.3
4725
10
30
50
Range 7
0
mph F
orm
ula
20.5
3309
10
20
8.44
BatterykWh
70
80
90
100
110
70
MotorkW
400
500
600
700
800
601.3
FDR
-100
100
300
500
700
900
1100
899
WeightReductionkg
0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4786
RatedSpeedFactor
Prediction Profiler
Profiler
Note: Battery size is Usable kWh
RSM R2 = 0.99
41© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 1 [80 mi]
10
40
70
100
130
Range F
TP
Form
ula
79.7
7395
10
30
50
70
90
Range H
WF
ET
Form
ula
72.7
9051
10
20
0-3
0 T
ime
Form
ula
4.5
04976
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
88453
60
80
100
120
Top S
peed
mph F
orm
ula
90.9
4564
10
30
60
80
110
Range 4
5
mph F
orm
ula
81.9
5155
10
30
50
Range 7
0
mph F
orm
ula
51.2
3838
10
20
24.06
BatterykWh
70
80
90
100
110
100.2
MotorkW
400
500
600
700
800
702
FDR
-100
100
300
500
700
900
1100
0
WeightReductionkg
0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
42© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 2 [80 mi]
10
40
70
100
130
Range F
TP
Form
ula
79.8
1661
10
30
50
70
90
Range H
WF
ET
Form
ula
69.8
3351
10
20
0-3
0 T
ime
Form
ula
4.4
55183
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
50771
60
80
100
120
Top S
peed
mph F
orm
ula
90.8
1802
10
30
60
80
110
Range 4
5
mph F
orm
ula
79.2
5614
10
30
50
Range 7
0
mph F
orm
ula
48.1
467
10
20
21.78
BatterykWh
70
80
90
100
110
89.1
MotorkW
400
500
600
700
800
702
FDR
-100
100
300
500
700
900
1100
255
WeightReductionkg
0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
43© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 3 [80 mi]
10
40
70
100
130
Range F
TP
Form
ula
80.2
289
10
30
50
70
90
Range H
WF
ET
Form
ula
66.7
34
10
20
0-3
0 T
ime
Form
ula
4.4
34153
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.9
47931
60
80
100
120
Top S
peed
mph F
orm
ula
94.7
7765
10
30
60
80
110
Range 4
5
mph F
orm
ula
76.9
6551
10
30
50
Range 7
0
mph F
orm
ula
44.4
1734
10
20
19.09
BatterykWh
70
80
90
100
110
74.34
MotorkW
400
500
600
700
800
670.2
FDR
-100
100
300
500
700
900
1100
591
WeightReductionkg
0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
44© Ricardo plc 2009RD.09/17905.3
Appendix A: Small SUV – Case 4 [80 mi]
10
40
70
100
130
Range F
TP
Form
ula
80.1
1264
10
30
50
70
90
Range H
WF
ET
Form
ula
63.6
8141
10
20
0-3
0 T
ime
Form
ula
4.3
87744
10
20
30
40
50
0-6
0 T
ime
Form
ula
9.7
66263
60
80
100
120
Top S
peed
mph F
orm
ula
95.5
0022
10
30
60
80
110
Range 4
5
mph F
orm
ula
73.7
5084
10
30
50
Range 7
0
mph F
orm
ula
41.4
9525
10
20
17.36
BatterykWh
70
80
90
100
110
70
MotorkW
400
500
600
700
800
663
FDR
-100
100
300
500
700
900
1100
812
WeightReductionkg0.4
0.4
5
0.5
0.5
5
0.6
0.6
5
0.7
0.4618
RatedSpeedFactor
Prediction Profiler
Profile r
Note: Battery size is Usable kWh
RSM R2 = 0.99
45© Ricardo plc 2009RD.09/17905.3
APPENDIX B –
ENERGY USAGE FTP vs. HWFET
46© Ricardo plc 2009RD.09/17905.3
1265 kJ Lower Rolling Resistance
[over 1 FTP75 cycle]
HWFET & FTP Energy Usage
Small Car, FTP75, Case 1: 1205 kg
[Regen = 20.9%]
Small Car, HWFET, Case 1: 1205 kg
[Regen = 5.3%]
Small Car, FTP75, Case 4: 627 kg
[Regen = 15.6%]
Small Car, HWFET, Case 4: 627 kg
[Regen = 2.8%]
1130 kJ Lower Rolling Resistance
[over 1 HWFET cycle]
47© Ricardo plc 2009RD.09/17905.3
APPENDIX C –
Brake Regeneration Plot
48© Ricardo plc 2009RD.09/17905.3
Small Car Brake Regen Example
Regen
brake
The EV motor and battery size allow for large
brake regeneration capture. No safety control
was implemented and a fixed threshold was
used to separate regen braking from
mechanical braking.
Note: Actual SOC range measured from 0.9 – 0.25
AMPS
FTP-75
