- SKF.com

Vehicle electrification &
hybridization
Edward Holweg
Director, Product and Systems Development
Capital Markets day 2010
Technology challenges in the automotive industry
Key business drivers:
• Wheel end weight & friction reduction
• Transmission technologies & efficiency
• Engine downsizing & boosting
• Engine management
• Vehicle electrification & hybridization
Tesla Roadster
CMD 2010
Future powertrain - Two main streams
Powertrain today
Powertrain optimization
- Downsizing
- Boosting
- Weight reduction
- Friction reduction
- New transmission solutions
CMD 2010
Powertrain electrification
- Micro-, Mild-, Full Hybrids
- Energy recovery systems
- Range extenders
- E-Motors
- E-Accessories
Electrification challenges
CMD 2010
Car OEMs tackle the challenges with different
technologies
CMD 2010
Current industry fleet average 2006
Targeted industry fleet average 2012
Electrical hybridization and electric vehicle
Micro hybrid, Stop-Start
Current industry fleet average, 2006
Targeted OEM fleet average, 2012
Micro/Mild hybrid, KERS
Mild hybrid torque assist
Full hybrid electric drive
Plug-in hybrid
Battery electric vehicle
Fuel cell vehicle
160
CO2 Fleet average (gr/km)
CMD 2010
130
CO2 gr/km
120 CO2 gr/km (2012-2015)
Sensor integration technology
- A key competence
CMD 2010
Sensor-bearing technology
Main advantages of tight air
gap control between target
and sensor body are:
1. Temperature variations vs
bearing stiffness performance
2. Smaller air gap limits
sensitivity to external
magnetic field
AIRGAP
Hall sensor Hall plate
Target
CMD 2010
Bearing
outer ring
Bearing inner
ring
Sensor-bearing benefits
Enhance e-motor performance
• Increase motor efficiency
– High accuracy (1°accuracy ~ 2% efficiency saving)
• Minimize motor noise
– High resolution reduces torque ripple
Magnetic
Reduce total cost and increase
compactness
• Design flexibility and easy to assemble
(one single part, performance checked)
CMD 2010
Motor efficient map versus
sensor accuracy
Motor NVH signature
according to resolution
SKF sensor-bearings for vehicle electrification
SKF Rotor Positioning
Sensor-Bearing Unit
SKF Motor Encoder
Sensor-Bearing Unit
Traction Motor
SKF Commutation
Sensor-Bearing Unit
SKF Commutation
Sensor-Bearing Unit
SKF Rotor
Positioning Bearing
Stop-Start
EPS Motor
SKF Rotor Positioning
Sensor-Bearing Unit
CMD 2010
SKF Rotor Positioning Bearing
Challenge
• Rotor angle measurement compatible with
existing customer production process for
alternator products
Innovative solution
• Customized impulse ring integrated within
bearing, leveraging on innovative magnet
material development
Benefits
• Powerful, accurate, repeatable and durable
impulse ring magnetic field
• High resistance to harsh running condition
• High integration into customer application
CMD 2010
In series production since 2008
SKF Rotor Positioning Sensor-Bearing Unit
Challenge
• Extremely accurate and repeatable permanent
magnet e-motor angle measurement, to
increase motor efficiency
Innovative solution
• To provide accurate/high resolution angle
measurement minimizing the non-linearity
error leveraging on bearing performance
Benefits
Sine and cosine output
• Accurate and repeatable output signal
• Modular output interface
• Scalable performances independent by
customer manufacturing process
• High magnetic field immunity
CMD 2010
Incremental output
Modeling and simulation
CMD 2010
SKF Vehicle Environmental Performance
Simulation tool
S
SKF software to translate bearing friction into real-life
fuel savings and CO2 reduction, for a complete vehicle
CMD 2010
SKF Vehicle Environmental Performance
Simulation tool
Bearing
Target
Target Bearing
Target
TargetSensor
Signal
Sensor Signal
Conditioning
Conditioning
Target
Target
• SKF Rotor Positioning
Bearing
Sensor
Sensor
Tools designed for a 6 Sigma approach
X’s
Controllable
&
Noise factors
• Shaft Position Sensor
• SKF Commutation
Sensor-Bearing Unit
Y’s
Response
ÆDefine the target value for each
parameter (Xs) to optimize the response
ÆDetermine the variability of the outputs
ÆPredict accuracy of the sensor-bearing
aannccee
Benefits: To get a better and quicker design “Right first time” bbaallaannccee rffoorrm
m
er
GGoooodd
biilliittyy
n ttoo ppe
ssiiggn
aarriiaab
e
v
e
Æ Determine the sensor-bearing accuracy including both customers
specification
D
v
s
D
/
r
s
e
/
r
ccoosstt paarraam
meette
o
t
o
t
n
and SKF design parameters influence
p
g
n
e
D
Deessiig siddeerriinngg tthhe
n si
ÆDecrease prototyping cost and quicker design to fit ccoon
the customer’s needs by adjusting the parameters
CMD 2010
Conclusions
The automotive industry is undergoing a rapid change due to fuel
consumption and CO2 regulations
SKF is developing solutions in the following areas
•
•
•
•
•
Friction and weight reduction
Transmission technologies & efficiencies
Vehicle electrification and hybridization
Engine management
Engine down-sizing & boosting
Vehicle electrification and hybridization
• Fully integrated sensors solution for e-motor control in hybrid and electrical
powertrain architectures
• Enhance e-motor performance (efficiency and noise)
• Reduce total cost and improve overall packaging
CMD 2010
CMD 2010