mild hibrid - 48 v - abdullah demir...48v mild hybrid systems market needs and technical solutions,...

MILD HIBRID - 48 V

Abdullah Demir, Dr.

Richard Kohler, BOSCH POWERTRAIN STRATEGIES, Powertrain Strategies for the 21stCentury Conference, University of Michigan, July 19th, 2017

ɛ=Compression RatioFR = Friction ReductionDI = Direct InjectionDZ= Downsizing w/ TurboSGDI = Stratified Lean BurnCDA= Cylinder Deactivationhigh ɛ= High CompressionBRS= Boost Rec. SystemCVT = Continuous VariableTra.cEGR= Cooled Exhaust GasAT8+ = 8/9/10 speedSimulation for FTP75 test cycle

Future PowertrainCO2 Reduction Roadmap

boost recuperation system (BRS)

Richard Kohler, BOSCH POWERTRAIN STRATEGIES, Powertrain Strategies for the 21stCentury Conference, University of Michigan, July 19th, 2017

48V Mild Hybrid Systems Market Needs and Technical Solutions, Ulf Stenzel, AVL Engineering and Technology, AVL UK Expo 2014 / Ulf Stenzel

12V/48V Electrical Architecture

48 VOLT: A PROVEN TECHNOLOGY TO REDUCE CO2 AND NOX EMISSIONS, www.clepa.eu, 2018

http://www.clepa.eu/

Electric Vehicle Architectures Nan Qin Oct. 17 2016

Power-Split Hybrid: Toyota Prius, Lexus CT200h, Lexus RX400h.Parallel Hybrid: Honda Insight Hybrid, VW Jetta Hybrid, Acura RLX Hybrid, Nissan Pathfinder Hybrid

http://www.bosch-presse.de/pressportal/de/media/migrated_download/de/BRS_Broschuere_RZ_en.pdf, 2013

Starter Motors and Generators - The BRS boost recuperation system:increased power, enhanced comfort and lower fuel consumption

http://www.bosch-presse.de/pressportal/de/media/migrated_download/de/BRS_Broschuere_RZ_en.pdf

48V Mild Hybrid Systems Market Needs and Technical Solutions, Ulf Stenzel, AVL Engineering and Technology, AVL UK Expo 2014 / Ulf Stenzel

12V/48V Electrical Architecture

Brian McKay, Ph.D., Benefits of a 48V P2 Mild Hybrid; www.continental-automotive.com; 30 September 2016 Powertrain Divisionhttps://www.arb.ca.gov/msprog/consumer_info/advanced_clean_cars/potential_efficiency_and_cost_benefits_of_48v_systems_and_synergistic_technologies.pdf

Powertrain Architecture - Optimized P2 Hybrid

http://www.continental-automotive.com/

48 VOLT: A PROVEN TECHNOLOGY TO REDUCE CO2 AND NOX EMISSIONS, www.clepa.eu, 2018

Range of 48V Technology Components DevelopedBy Clepa Members Today

http://www.clepa.eu/

https://www.powerelectronicsnews.com/technology/whatever-happened-to-the-42-volt-bus

For hybrids vehicles, there is actuallya “roadmap” for 48-V integration.The ratings (P0 through P4) actuallysignify the degree of electrification,where P0 signifies support forstop/start and P4, where almost allautomotive appliances derive powerfrom the motor/generator.Source: Continental (as reported by Jalopnik https://jalopnik.com/everything-you-need-to-know-about-the-upcoming-48-volt-1790364465 )

https://jalopnik.com/everything-you-need-to-know-about-the-upcoming-48-volt-1790364465

Cossale, Marco (2017). Multi-phase Starter-Generator for 48 V Mild-Hybrid Powertrains. PhD thesis, http://porto.polito.it/2667599/ since: March 2017; Published version: DOI:10.6092/polito/porto/2667599


Inverter: convert DC to AC

48 Volt Hybrid with e-drive features - Excellent fuel efficiency and Drivability; Electric & Electronic Systems in Hybrid and Electrical Vehicles and Electrical Energy Management ,17. – 18.05.2017, BambergStefan Lauer (Dr. rer. nat.), Continental Automotive GmbH, Regensburg; Friedrich Graf (Dipl.-Ing.), Continental Automotive GmbH, Regensburg; Moritz Springer (Dipl.-Ing.), Ford Werke GmbH, Cologne; Stefan Wechler (Dipl.-Ing. (FH)), Schaeffler Technologies AG

& Co.KG, Herzogenaurach

Figure 1: System architecture of the 48 volt P2 hybrid vehicle ‘GTC2’



P2 - System ArchitectureThe so-called P2 hybrid architecture was chosen for the GTC2 with the electric traction machine and theadditional K0 clutch being installed between the internal combustion engine (ICE) and the transmission (Figure1). Hence drag losses in hybrid states such as recuperation, coasting (rolling with open powertrain), sailing(driving electrically at constant speed) and pure electric driving are eliminated (Figure 2).Special aspects of the chosen configuration are on one hand the integration of the 48 volt electric machine andfurthermore of the standard mechanical climate compressor in an axial parallel configuration. Adding an electricin lieu of a conventional coolant pump it is thus possible to discard the conventional front end accessory drive.On the other hand, a manual transmission car was selected to demonstrate the feasibility of a hybrid conceptwhich avoids the additional on-cost of an automated transmission system.The combustion engine is the Ford 1.0L EcoBoost three cylinder gasoline engine modified with a highercompression ratio (CR=12.0) in combination with a ‘late intake valve closing’ concept. It is enhanced by anaccordingly matched RAAX turbocharger [1], a 200 bar fuel pressure injection system, an electrically heatedcatalyst (EHC, brand name EMICAT) and an engine control unit coordinating the entire powertrain. To counteractthe problem of knocking but also to further increase part load engine efficiency, the intake cam event length issignificantly increased (Late Intake Valve Closing (LIVC)). A further key engine component is the RAAXturbocharger with a low inertia radial-axial turbine, which generates high boost pressure and fast pressure buildup even at low engine speeds. At the same time, with high gas flow rate at the rated power point, the exhaustgas back pressure does not increase as strongly as it does with a standard turbocharger.



P2 - System Architecture (cont.)To comply with the emission legislation requirements and to maximize CO2 savings, anelectrically heated catalyst (EHC) is selected as ideal partner for a P2 hybrid system with itsfrequent engine shut downs. The implemented EHC is a metal foil catalyst with an operatingvoltage of 48 volt. It can be heated up rapidly with an electric power of 4 kW to its light offtemperature required for effective feed gas conversion.From installation point of view, the centerpiece of the P2 system is a compact ‘hybridmodule’ which is integrated between the internal combustion engine (‘ICE’) and the manualtransmission meeting the package requirements of an east-west installation. It comprises ofa housing, a drive clutch (K1) and a decoupling clutch (K0), a belt drive system withdecoupling tensioner, an electric machine with integrated power electronics and aconventional mechanical climate compressor. The E-machine is connected with an effectivetransmission ratio of 2.7 to the driveline. Both clutches K1 and K0 are designed as normallyclosed friction clutches and are controlled by corresponding clutch actuators along with adedicated clutch control software.



Figure 2: Powertrain operating states

Uli Christian Blessing , 48V: How much hybridization is possible with the new vehicle power?, 14th International VDI Congress, Friedrichshafen, GETRAG, 14th International VDI Congress, Drivetrain for Vehicles, Friedrichshafen June 2014, Uli Blessing

48V Comparison: Belt vs. Flanged vs. Integrated Solution

Remark: For simplicity reasons, only these three main-stream examples have been chosen


48V Comparison: Belt vs. Flanged vs. Integrated Solution

* depending on battery performance


Motivation for the 48 V P2 Topology

P2 topology attributes• Located between ICE and transmission• Max. recuperation capability (reduced drag

torque)• Engine-off coasting• Engine-off recuperation• Pure electric drive (‘active’ sailing)• Electric launch + electric creeping• Conservation of air conditioning (engine-off

coasting, S/S phases)



Clutch Module


https://www.powerelectronicsnews.com/technology/whatever-happened-to-the-42-volt-bus

Continental’s P2 design features adrivetrain pulley sandwichedbetween the engine andtransmission — and isolatedclutches when the vehicle ispowered with only electric power.When the engine-side clutch opens,the motor spins the transmissioninput shaft with the belt and drivetrain pulley.Source: Continental (as reported by Jalopnik) https://jalopnik.com/everything-you-need-to-know-about-the-upcoming-48-volt-1790364465

Belt Drive

https://jalopnik.com/everything-you-need-to-know-about-the-upcoming-48-volt-1790364465


Hybrid Transmission Kit: From 48V up to 360V Plug-In Hybrid

Changed stator windings and power connectors ensure easy scalability

Powertrain Electrification for the 21st Century by Dr. Matti Vint PTS Engineering R&D Director, 07/23/2014

By areas, Powertrain needs seem different…


In reality there are large similarities in each segment


Primary Electrification - Classification Groups


System Comparison Hybrid systems vs main functions


FE Benefits from Stop-Start to 12v-48v Hybrids


Electric Supercharger - A smart way to use ‘free’ regen energy

mild hibrid - 48 v - abdullah demir...48v mild hybrid systems market needs and technical solutions,...

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