3. Before We Start
This webinar will be available afterwards at
www.designworldonline.com & email
Q&A at the end of the presentation
Hashtag for this webinar: #DWwebinar
5. 10 April 2014 – Design World
Examining the difference in energy consumption
between a PMAC and an induction motor over various
drive cycles and how this impacts battery costs
Speaker/Co-author: Jay Schultz
Industry Market Manager
Vehicle Electrification
jschultz@parker.com
707-584-2417
Division: Electromechanical Division
North America
www.parker.com/hev
6. Outline
• About Jay Schultz
• About Parker Hannifin
• The HEV
• Electric Motors
• Induction Motors
• PMAC Motors
• The usage cycle
• Conclusions
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7. Jay W Schultz
• Industry Market Manager
• Leading product management
• Global marketing strategy
• Key business development
• Spoken at numerous industry
events on the subject of
motors
• Find/Connect with me on
LinkedIn
• QR Code to Download Full
Paper
http://www.linkedin.com/in/jaywschultz
www.parker.com/hev www.parker.com/racing
10. The HEV – Hybrid Electric Vehicle
• Powertrain
• Electric motors placed in the driveline to deliver
power to the wheels to help assist the engine
• Hydraulic Implement
• Hydraulic pumps are removed from PTO and electric
motors are then connected to hydraulic pump
• Engine can be off while electric motor provides power
to the hydraulic system
www.parker.com/hev www.parker.com/racing
11. The HEV – Hybrid Electric Vehicle
1. Internal combustion
engine (ICE)
2. Electric generator
3. Generator controller
4. Battery pack
5. Motor controller
6. Electric Motor
7.Axle/Wheel assembly
(powertrain)
8. Hydraulic pump
(EHA/ePump)
Powertrain
Electro-hydraulic/ePump
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12. Focus on Electric Motors
• When an OEM has a hybrid electric program,
two major motor choices:
• Induction Motors
• Permanent Magnet AC (PMAC) Motors
• IMs and PMAC motors are very similar
• Housings
• Shafts
• Copper
• Steel
• Electrical cables
• More
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13. Focus on Electric Motors
• Major Differences are in the rotor inserts:
Induction Motor:
Copper or aluminum
inserts
PMAC: Rare earth
permanent magnet
inserts
Isometric view. Induction motor active parts.
(Drawing source: www.infolytica.com)
www.parker.com/hev www.parker.com/racing
14. Focus on Electric Motors
• What areas are impacted when exchanging
copper bars for permanent magnets?
• Speed and torque characteristics
• Physical size and weight
• Efficiency
• Material costs
• Energy consumption over usage cycle
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15. Focus on Electric Motors
• Before moving on, we must create a fair
scenario
• Look at a “real” application, with real requirements
• Keep all other hybrid system parameters and
components constant
• Voltage and current on inverter
• Battery pack voltage and energy storage
• Create a PMAC motor and induction motor that
meets vehicle specifications
• Compare differences
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16. Focus on Electric Motors
• Required Vehicle Specifications
• This is a real customer requirement
• Vehicle specifics
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17. Focus on Electric Motors
• Software Methods
• Finite element analysis models used to create an optimized
induction motor and PMAC motor to meet specifications
• A variety of operating points were simulated and interpolation
used when a desired point fell between two simulated points
• Thousands of FEA simulations required for results
• Assumptions
• Both motors run at most efficient points
• Slip was adjusted (IM) to meet maximum efficiency
• Both motors have sufficient cooling, not necessarily equal
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18. Focus on Electric Motors
• Speed and Torque Characteristics
Required operating points
• Induction Motor (run at max efficiency)
• Tp = 600Nm, Pp = 115kw
• Tc = 300Nm, Pc = 60kw
• Top speed = 5000 rpm
• Meets all given specs
• PMAC Motor
• Tp = 600Nm, Pp = >200kw
• Tc = 400Nm, Pc = 160kw
• Top speed = 5000 rpm
• Meets and exceeds given specs
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19. Focus on Electric Motors
• Physical size and weight
• Induction Motor
• Volume: 15.5 liters
• Weight: 72.8 kg
• PMAC Motor
• Volume: 9.8 liters
• Weight: 49.8 kg
LIM
LPMAC
DPMAC
DIM
Dimensions of Active IM Components Value Unit
Diameter 290 mm
Length 234.4 mm
Total Volume 15.5 L
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20. Focus on Electric Motors
• Electromagnetic efficiency
• Does not include mechanical losses
• Induction Motor
• Lower efficiency across most
regions
• Best efficiency at low torque
and high speed
88%
90%
92%
• PMAC Motor
• Very large “sweet” spot for efficiency
• Lower losses at peak torque
• Higher losses at low torque and high
speed
90%
92%
94%
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21. Focus on Electric Motors
• Material costs of active components
• Based on actual procurement costs
• No labor or overhead
• No amortized tooling
Induction Motor: Copper
or aluminum inserts
PMAC: Rare earth
permanent magnet inserts
Isometric view. Induction motor active parts.
(Drawing source: www.infolytica.com)
www.parker.com/hev www.parker.com/racing
22. Focus on Electric Motors
• Initial Conclusions
• IM takes up ~60% more volume
• PMAC is ~32% lighter
• Max efficiency is comparable
• Both meet torque and power specs
• Active material of induction motor is 26% less
expensive
• If size and weight are not factors, Induction
Motor seems more attractive
• PMAC more attractive if weight and size are
important considerations
www.parker.com/hev www.parker.com/racing
23. The Usage Cycle
• What impact does “use” have?
• What losses are present at certain points
• Low speed, high torque
• Mid speed, mid torque
• High speed, low torque
• Looking at the energy over a usage cycle and total
losses
• Highly dynamic cycle, city driving
• Low dynamic cycle, rural driving
• Constant speed, freeway driving
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24. • Operating Point #1: Low Speed, High Torque
• Total Losses of PMAC = ~6kW
• Total Losses of IM = ~17kw (almost 3x)
The Usage Cycle
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PMAC IM
25. The Usage Cycle
• Operating Point #2: Mid Speed, Mid Torque
• Total Losses of PMAC = ~1.2kW
• Total Losses of IM = ~2.7kw (over 2x)
PMAC IM
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26. The Usage Cycle
• Operating Point #3: High Speed, Low Torque
• Total Losses of PMAC = ~1.2kW (over 1.3x)
• Total Losses of IM = ~0.9kw
PMAC IM
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27. The Usage Cycle
• Those three points give insight into what to look
for in a usage cycle
• How often does the motor change power points?
• How drastic are the changes between power points?
• How long does the application require the motor to
operate at each power point?
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28. The Usage Cycle
• Highly Dynamic Usage Cycle – City Driving
• Characterized by frequent changes in velocity
• Exhibits large amplitude
• Low to mid speed range (of the motor)
• Tendency for short periods (<50s)
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29. The Usage Cycle
• Highly Dynamic Usage Cycle
• Powertrain: City driving
• Average Speed: 7mph
• As this cycle is repeated, the PM motor would use 1
kwhr per hour less of stored energy
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30. The Usage Cycle
• Moderately Dynamic Usage Cycle – Rural Driving
• Characterized by less frequent changes in velocity
• Amplitude of demand, still might be high
• Medium speed range (of the motor)
• Much longer periods (150s to 300s)
• Average speed of ~30mph
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31. The Usage Cycle
• Moderately Dynamic Usage Cycle
• Powertrain: rural driving
• Average Speed: ~30mph
• As this cycle is repeated, the PM motor would use
0.3 kwhr per hour less of stored energy
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32. The Usage Cycle
• Low Dynamics Usage Cycle – Freeway Driving
• Characterized by little (or no) change in velocity
• Smaller amplitudes between peaks and valleys
• Higher speed range (of the motor)
• Very long periods, or rise to a constant demand
• Average speed: 57mph
RequiredPower
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33. The Usage Cycle
• Low Dynamics Usage Cycle
• Powertrain: freeway driving
• Average Speed: ~57mph
• As this cycle is repeated, the PM motor would use
0.1 kwhr per hour less of stored energy
www.parker.com/hev www.parker.com/racing
34. Conclusions (Value in use)
• PMAC motors are more efficient over a dynamic
usage cycle enabling lower energy storage costs
• $1000 to $30000 per vehicle in energy storage costs
• 35% less energy used yields:
• Cost reduction of $350 to $10500 per vehicle
• Significantly increased range per charge (customer proven)
• PMAC preferred choice when:
• Vehicle is very sensitive to size and weight
• If the application has a highly or moderately dynamic
usage cycle
• Large operating region of the motor is required
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35. Conclusions (Value in use)
• Induction motors have ~26% less upfront cost
than PMAC. Preferred choice when:
• Applications with higher constant speed and low
power draw
• Dynamic efficiency not a concern
• Size and weight optimization of vehicle are negligible
• Narrow performance range
www.parker.com/hev www.parker.com/racing
36. Examining the difference in energy consumption
between a PMAC and an induction motor over various
drive cycles and how this impacts battery costs
Speaker/Co-author: Jay Schultz
Industry Market Manager
Vehicle Electrification
jschultz@parker.com
707-584-2417
Division: Electromechanical Division
North America
www.parker.com/hev
10 April 2014 – Design World
39. CONFIDENTIAL DOCUMENT
The EV Motorcycle Exposed
39
Brammo Empulse R Production Electric Motorcycle
9.3 kWh Li-Ion Battery Pack
3kW on-board charger
42kW / 90Nm PMAC Motor
110 mph Top Speed
470 lbs.
Packaging, Weight, and Performance
40. CONFIDENTIAL DOCUMENT
Search for a new motor…
40
• PMAC showed promise in the 2009 race over brushed DC and ACIM
motors, but needed a custom, traction focused solution.
• Of 2 Brammo bikes entered in the 2009 IOMTT race, only one finished
due to motor overheating and demagnetization.
• In 2010, Brammo began working with Parker-Hannifin on a new bike
with a development of their “MPT” PMAC motor.
41. CONFIDENTIAL DOCUMENT
ACIM vs. PMAC for EV Racing Applications
41
PMAC preferred by Brammo due to:
Reduced Packaging Size and Weight
Torque/Speed characteristics supports a direct
drive or single stage reduction.
Lower rotor losses at high torque (racing
applications) lowers the cooling system
requirements.
More flexibility with magnetics architecture
(specific to Parker’s GVM design)
Great technical team and working relationship.
ACIM @ ~120kW PMAC @ ~120kW
550 lbs. 470 lbs.
42. CONFIDENTIAL DOCUMENT
Technology Development = High Pace
42
NOW2009
3.1 kWh 6.2 kWh 9.3 kWh
2x 3x
7.9 kWh
55 HP
90 mph
14.3 kWh
170 HP
170+ mph
Keeping pace with Tesla
87 Wh/kg 99 Wh/kg
145 Wh/kg
79 Wh/kg
129 Wh/kg
~125 Wh/kg
43. CONFIDENTIAL DOCUMENT
Brammo Powertrain Tech Overview
43
Samarium-Cobalt (SmCo) Internal Permanent Magnet (IPM)
motor developed for production with Parker-Hannifin through
Brammo Racing program.
Multiple diameters and stack lengths for different torque/power
levels. i.e. Flexible product architecture – scales up or down.
High continuous power (vs. just peak power) due to magnetics
design and Brammo’s cooling design. Smaller motors can be
used for a given application.
Transmission provide an option to do more with less. i.e. the
equivalent performance direct-drive system would be 1.5x the
power requirement.
PMAC EV Drivetrain Benefits:
High Specific Power/Volume
High Torque at low RPM w/good
efficiency.
Good speed range for traditional gear
ratios.
Good overall efficiency makes the most of
the on-board energy capacity.
44. CONFIDENTIAL DOCUMENT
Key Technology Focus – Systems Approach
44
Strong systems approach and understanding
will allow for more integrated solutions over time.
Range and performance improvements are not
just a battery problem.
Capturing and understanding data is key to
Brammo’s understanding and optimization of EV
systems.
Range Determined by:
Battery Capacity
System Efficiency
Charge Rate
47. Thank You
This webinar will be available at
designworldonline.com & email
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