SuperGen – Novel low cost electro-mechanical mild hybrid

engineering the future

SuperGen – Novel low cost electro-mechanical mild hybrid and boosting systems for engine efficiency enhancements2nd Conference on Engine ProcessesJuly 02-03 2015, Berlin

Contents

• Quick overview of Integral Powertrain• Supergen Concept• Analysis of results• Test results from UltraBoost engine• Summary

Highly Confidential Integral Powertrain Ltd | Page 2

Integral Powertrain

Overview• UK-based powertrain engineering consultancy

• Founded in 1998 by the former Cosworth engineering management team

• ~170 engineering staff

Core Business• Powertrain and controls engineering

• E-Drive Systems engineering & manufacture

• JV business with Magna (high volume industrialisation of SuperGen)

Innovation• Electric machines and hybrid drives

• Boosting and turbo-compounding

Facilities• Engineering Centre and low volume E-Motor manufacturing, Bletchley,

Milton Keynes

• Emissions and Climatic Test Centre, Kiln Farm, Milton Keynes

• JV company location in Tanners Drive, Milton KeynesHighly Confidential Integral Powertrain Ltd | Page 3

Contents



• E1 is connected to the input and drives the annulus of the traction drive

• E2 is connected to the planet carrier of the traction drive

• Compressor input shaft is connected to the sun wheel

• Therefore the speed of E2 modifies the speed of the compressor

• E1 and E2 can be clutched together for stop-start, mild hybridization

• System replaces the alternator and is voltage agnostic

SuperGen B-ISG Subsystems


1. FEAD pulley, 2.5-3.5:1 ratio

2. Electrical machine, E1

3. Electrical machine stator(s)

4. Epicyclic traction drive, ~10:1 ratio

5. Electrical machine, E2

6. Bearing system

7. Radial flow compressor

8. Compressor Diffuser

9. Cooling jacket (Charge-cooler circuit)

10. Integrated 14V MOSFET inverters

11. Input shaft, connected to pulley & E1

12. Annulus

13. Planet

14. Planet Bearing

15. Planet carrier, connected to E2

16. Sun-shaft, connected to compressor

17. Compressor

• Mild hybridization • Stop/start, torque assist, anti-stall and other mild hybrid functions• Maximum brake energy recuperation between 4 and 17 kW depending

on version

• Boosting system • Independent of the vehicle battery (self-sustaining) - capable of

continuous operation • Traction drive planetary transmission – roller bearing technology

without gear teeth• Planetary ratio, Annulus/Sun, R 10:1, belt ratio typically R2 ~ 3.5

• Input power can split between the mechanical and electrical paths• Transmission is more electrical at low speeds, tending to 100%

mechanical at higher speeds• Steady-state boost is unaffected by a depleted battery• Higher boost performance and self-sustaining for less system cost

• System capable of up to 15 kW boost at 12 V

SuperGen operating functions


Contents



Base vehicle• SUV, ~1750kg Kerb Weight• 2.0L DI VVT W/G T/C ~100kW/L gasoline engine• 8/9-speed transmission, Stop-start as standard• NEDC cycle, CO2 = 163g/km

SuperGen system added to 2.0L baseline in the high-pressure (HP) position after LP turbocharger. Analysis conducted to investigate SuperGen benefits from: • Stop-start as per baseline system (no change to CO2 but more refined)• Further down-speeding by 20%• Hybrid functions (i.e. regenerative braking and torque assist) between 6kW and 10kW

for 14V, 14kW and 17kW for 48V• Supporting advanced combustion strategies i.e.. Miller cycle (early or late IVC), Dilute-

Homogenous, Stratified-Lean Burn• Extending down-sizing even further

SuperGen fuel economy analysis – baseline assumptions


Baseline Engine Results• Results summary for baseline combustion system• Down-speeding benefit 8.2g/km (5%) due to longer gearing• Regenerative braking benefit at 6kW is an additional 7g/km (4.3%)• Further reductions with increased power capability are limited by

available energy after road-load, aerodynamic drag, engine friction and other driveline drag losses

• 8kW 8.1g/km (5.0%), 10kW 8.9g/km (5.5%), 14kW 9.6g/km (5.9%), 17kW 10.2g/km (6.2%)

Summary• 14V SuperGen on ‘standard’ 2.0L engine can deliver up to -10.5%

CO2, +12% on mpg

SuperGen fuel economy analysis – results summary


Advanced Combustion Strategies Interactions & System Simulation Results• Utilise the Miller-cycle and/or advanced charge motion and EGR to extend knock limit (CR increase), reduce pumping and heat-rejection losses and

therefore achieve higher cycle efficiency• Most strategies not suited to pure turbocharged system due to the conflict between available exhaust enthalpy, compressor and turbine match and

combustion requirements• ‘Basic’ Miller-Cycle with increased compression ratio and three-way catalyst – 5%• Dilute homogenous mode with high EGR but Lambda=1 overall – 8%• Lean homogenous mode with EGR and true lean operation - LNT required for highest gains - 12%• Overall results with SuperGen, down-speeding and regen ranged from 15-22%

Future Stretch Opportunity to Down-size to >130kW/L• Results have indicated potential to down-sizing to over 130kW/L• Down-sizing to 1.6L vs. 2.0L reduces CO2 by further 9g/km (5%)• 14V SuperGen with conventional engine can deliver up to -16% CO2, +19% on mpg• With adv. combustion system this extends to -26% CO2 or +35% on mpg

SuperGen fuel economy analysis – results summary


Contents



Original UltraBoost charging system

• The original Ultraboost charging system comprised a Honeywell GT30 turbocharger (LP) and an Eaton R410 supercharger (HP)

• Charge coolers were provided both between the stages and after the supercharger

• To provide high system effectiveness at all times• A bypass was provided for the R410, which was clutched out above

3000 rpm• The system could not deliver target steady-state torque below 1500

rpm


HP Stage:Eaton R410

LP Stage:Honeywell GT30

Charge Coolers

UB200 Full-load performance


225

250

275

300

325

350

375

0

100

200

300

400

500

600

0 1000 2000 3000 4000 5000 6000 7000

BSFC

/ [g

/kW

h]

Torq

ue /

[Nm

]

Engine Speed / [rpm]

AJ133 Torque UB200 Torque UB200 BSFC

Exceeding the torque target above 1500 rpm proved straightforward

Peak torque and power targets were

met

The only project miss was in terms of low-speed

torque <1500 rpm

Full load, steady state: SuperGen matching AJ133 torque


250

300

350

400

450

500

550

0

100

200

300

400

500

600

750 1000 1250 1500 1750 2000 2250

Obs

erve

d B

SFC

/ [g

/kW

h]

Cor

rect

ed T

orqu

e / [

Nm

]

Engine Speed / [rpm]

AJ133 Torque SG matching AJ133 Torque UB200 TorqueUB200 BSFC SG matching AJ133 BSFC

1000 rpm torque now 358 Nm v 283 Nm for R410 (+26.5%)

Full-load target now met from 1250 rpm

Increase in BSFC over Eaton due to work associated with 75 Nm

greater torque generation

Same valve timing

Valve timing optimization improved 1000 rpm to 337 g/kWh and 1500

rpm to 263 g/kWh

2500rpm Torque Response on UltraBoost engine


0

100

200

300

400

500

600

0 1 2 3 4 5

Torq

ue /

[Nm

]

Time / [s]

2500 rpm Turbo Only 2500 rpm Turbo plus SuperGen

2500 rpm runs with and without SuperGen

At 2500 rpm, the target full-load performance is 478 Nm

With SuperGen, 10-90TTT is <1.2 s

Transient performance tests: 1000rpm torque response


0

50

100

150

200

250

300

350

400

0 1 2 3 4 5 6 7 8 9 10

Obs

erve

d To

rque

/ [N

m]

Time / [s]

SuperGen matching AJ133 torque SuperGen matching UB200 torque UB200

10-90% Time-to-Torque (s)

UB200/Eaton Baseline 2.52

SuperGen matching AJ133 torque 2.11

SuperGen matching UB200 torque 0.80

68% reduction in matched 10-90% TTT

Contents



Summary

• SuperGen can provide class leading mild hybrid capability with peak recuperation power potentially approaching 20 kW• However, due to the cost versus capability / life of the energy storage mediums required for optimum mild hybrid

performance, the best £/CO2 trade-off is achieved at 12V• SuperGen was designed as a boosting system with class leading response and sustainable, continuous operation

compressor powers beyond any pure e-Booster system• The boosting capability enables extreme downsizing and down speeding of both gasoline and Diesel engines

• The UltraBoost project has shown that SuperGen’s ability to improve low-speed torque and transient response may enable downsizing to be taken beyond 60%, with further significant fuel economy potential

• The ability to generated sustained mass flow and pressure ratio largely independent of engine speed and load also enables advanced combustion strategies in gasoline engines for significant thermal efficiency improvements and thus further reductions in fuel consumption

• Similarly, more capability can be added to Diesel engines at part load for emissions optimisation using SuperGen as an EGR pump for example


Questions?

Confidential Integral Powertrain Ltd | Page 19

Engineering Centre (EC)Denbigh RoadBletchleyMilton KeynesBuckinghamshireMK1 1DBUnited Kingdom+44 (0)1908 278 600

Emission and Climate Test Centre (ECTC)BrunleysKiln FarmMilton KeynesBuckinghamshireMK11 3EWUnited Kingdom+44 (0)1908 776 725

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SuperGen – Novel low cost electro-mechanical mild hybrid