the best motor for hybrid electric vehicle powertrains

The Best Motor for Hybrid Electric

Vehicle Powertrains

Thank You To Our Sponsor

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

http://www.designworldonline.com/

Moderator Presenters

Miles Budimir

Design World

Brian Wismann

Brammo

Jay SchultzParker Hannifin

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

[email protected]

707-584-2417

Division: Electromechanical Division North America

www.parker.com/hev

mailto:[email protected]

Outline

• About Jay Schultz• About Parker Hannifin• The HEV• Electric Motors• Induction Motors• PMAC Motors

• The usage cycle• Conclusions

www.parker.com/hev www.parker.com/racing

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


http://www.linkedin.com/in/jaywschultz

Parker Hannifin Today


$13 Billion Sales8 Product Groups140 Divisions250 Plants WW1,200 Markets2,750 Product Lines8,600 Distributors50,000 Employees525,000 Customers

1,000,000 ProductsHeadquarters - Cleveland, Ohio

Customer-Centered Structure


SealAerospace

Instrumentation

Fluid ConnectorsAutomation

Hydraulics

Automation Group:• Vehicle Electrification

• Traction, ISG, Aux• Vehicle Pneumatics

Climate & Ind’l Controls Filtration

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


The HEV – Hybrid Electric Vehicle

1. Internal combustion engine (ICE)2. Electric generator3. Generator controller4. Battery pack5. Motor controller6. Electric Motor7.Axle/Wheel assembly (powertrain)8. Hydraulic pump (EHA/ePump)

Powertrain

Electro-hydraulic/ePump


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



• 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)



• 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



• 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



• Required Vehicle Specifications• This is a real customer requirement

• Vehicle specifics



• 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



• 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



• 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 UnitDiameter 290 mmLength 234.4 mm

Total Volume 15.5 L



• 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%



• 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)



• 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


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


• Operating Point #1: Low Speed, High Torque

• Total Losses of PMAC = ~6kW• Total Losses of IM = ~17kw (almost 3x)

The Usage Cycle


PMAC IM

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


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


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?


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)


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


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


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


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

Req

uir

ed P

ow

er


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


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


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


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

[email protected]

707-584-2417

Division: Electromechanical Division North America

www.parker.com/hev

10 April 2014 – Design World


CONFIDENTIAL DOCUMENT

Brammo MotorcyclesCase Study

Design World Webinar / 4.10.2014

37


Brian Wismann Introduction

38


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 Speed470 lbs.

Packaging, Weight, and Performance


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.


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.


Technology Development = High Pace

42

NOW20093.1 kWh 6.2 kWh 9.3 kWh

2x 3x

7.9 kWh55 HP

90 mph

14.3 kWh170 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


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.


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


3 Seasons of Racing Success w/ PMAC

45

2012

2011

2013

Questions?

Miles Budimir

Design [email protected]: 440.234.4531Twitter: @DW_Motion

Brian [email protected]: 541-482-9555 ext.301Twitter: @BrammoDesigner

Jay SchultzParker [email protected] Phone: 707-584-2417




Thank You

This webinar will be available at designworldonline.com & email

Tweet with hashtag #DWwebinar

Connect with Design World

Discuss this on EngineeringExchange.com

http://www.designworldonline.com/

http://www.engineeringexchange.com/