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Mild Hybrid cOst effective solutions for a fast Market penetratiON

Periodic Reporting for period 2 - THOMSON (Mild Hybrid cOst effective solutions for a fast Market penetratiON)

Reporting period: 2018-04-01 to 2020-03-31

Internal Combustion Engines (ICE) have reached today a high level of maturity, with an outstanding competitiveness with regard to the flexibility in use, being able to support a multiple combination of vehicle mission profiles. Nevertheless, to further and significantly reduce CO2 and pollutant emissions for post 2020 standards, the electrification of the powertrain will be a fundamental step, with a more important role (and beneficial effect) especially in high traffic density conditions in large urban agglomerations, where noxious pollutant emissions (especially NOx) are of most concern. In this context, the THOMSON project addresses very precise and consistent objectives to support a quick transition towards highly efficient, cleaner and affordable electrified powertrains, focusing on 48V architectures. The aim is to demonstrate how the right combination of advanced engine downsizing plus turbocharging technologies, coupled with a 48V motor-generator system, can provide the most cost-effective solution for a rapid electrification through conventional vehicles.
Conclusion of the action
The overall technology packages, for both demonstrator vehicles developed in the project, showed positive tendencies to accomplish future legislative boundaries (Euro 7 scenario) without further additional technologies. The technologies developed achieved the objective of demonstrating cost effective and optimised mild hybrid vehicles, and the tools and approaches developed will enable a fast market penetration by mitigating any potential adverse impacts on product time and cost because of the associated increase in vehicle complexity.
The following main results have been achieved in the project:
• Advanced cost-effective boosting system: The main focus of the project was a 2-stage electrified boosting system including turbocharger and electrically driven compressor. The system design trade-off was explored, to deliver the air handling to achieve engine power targets. A topology optimization process was also developed and applied to the intake ductwork, to optimize the flow into the second stage, achieving a 2% improvement in compressor efficiency. The project also looked at exhaust temperature management for diesel engines, with the introduction of an inner insulated turbocharger technology. A system model was developed and integrated into the energy optimization framework to show the potential of a 3% fuel consumption improvement at iso-NOx. An engine-independent transient boosting system test facility was created to demonstrate the benefits of this boosting system.
• Emission, energy and thermal management: development of a high-fidelity total vehicle model, representing both hybrid demonstrator vehicles. The toolchain developed is capable of identifying improved vehicle attributes at the same product cost and, incorporating a cost model, can inform cost/benefit decisions. Furthermore, it is also able to identify additional CO2 benefits from control strategies with complex interactions and reduces hybrid product development times. The impact of the technologies developed are significant reductions in the fuel consumption and pollutant emissions for future hybrid vehicles, achieved in a cost-effective manner.
• CRF together with Bosch, Faurecia and PoliMi developed a 48V mild hybrid demonstrator vehicle based on a FIAT 500X MT6 FWD equipped with a diesel 1.6 litre engine updated with a belt-starter generator (BSG), new boosting and EGR systems, and an advanced close coupled aftertreatment system including AdBlue dosing and “SCR on filter” catalyst, metallic DOC and electric Heated Catalyst (eHC). The assessment in terms of performance showed that the right matching of a new power-oriented turbocharger with the 48V eBooster allowed similar steady state and better transient performance to be achieved when compared to the reference 2.0 litre 140hp diesel engine. Thanks to engine downsizing (from 2.0 to 1.6 litres), new technologies (LP EGR, WCAC and VGT) and mild electrification, the vehicle demonstrated the achievement of the CO2 target (16% reduction on WLTC with respect to 500X 2.0 litre) and the fulfillment of all the emissions limits within Euro 6d final regulation. Moreover, it has been demonstrated that the use of 48V eHC clearly shows the potential to further reduce CO, HC and NOx emissions well below the current Euro 6d final threshold, both on the homologation cycle and under real driving conditions. In this perspective, a part of recovered energy needs to be used to heat the catalysts and, therefore, the CO2 benefit could be slightly reduced. Finally, the validation tests: WLTC and RDE tests performed in Ispra at the JRC (Joint Research Center) confirmed that the CRF demonstrator 500X 1.6 litre diesel achieved both the CO2 and emissions targets.
• Ford with his partners developed a C-Max 1.0 litre CNG mHEV with a P2 electric motor, new boosting (including eBooster), aftertreatment system with eHC and a 12/48V battery. The chosen P2 mild hybrid (48V) powertrain topology in combination with a modern, dedicated MTDI (Methane Turbo Direct Injection) internal combustion engine, fulfilled the project targets with regard to pollutant emissions, performance, driveability, cost and CO2 reduction. Furthermore, this powertrain concept enabled the development and integration of an altered level of 48V HEV user-experience introducing electrical manoeuvres and a two-pedal approach with a manual transmission. The 48V system was also used to implement an advanced boosting system. Concerning RDE, the demonstrator vehicle revealed that a CF=1 can be considered as feasible on this powertrain architecture and its performance can be at least designed to be equal or even better than a 1.5 litre EcoBoost derivative, but at approximately 34% lower CO2 emissions.
Dissemination: 19 actions were carried out along the project timeframe.
Approaches developed in the THOMSON project have demonstrated how the right combination of advanced engine downsizing plus turbocharging technologies, coupled with a 48V motor-generator system, can provide the most cost-effective solution for a rapid electrification through conventional vehicles. Thanks to the results obtained with the FIAT 500X, it is possible to state that this technology package is clearly an interesting solution for diesel applications to be considered in the 2025 timeframe, where the Euro 7 emission regulation needs to be fulfilled and further CO2 reduction is required to guarantee the new fleet targets. Concerning the mild hybrid technology developed by Ford on a CNG engine, the very good results obtained instil confidence in the possibility of introducing plug-in hybrid solutions based on just a 48V board-net, simplifying discussions around electric power supply infrastructure for plug-in hybrids enormously by simply using conventional, usual power sockets. Finally, the cost/benefit analysis performed by Ricardo showed that both demonstrator vehicles achieved excellent cost/benefit ratios compared to other technologies, thanks to the combination of the 48V systems and the advanced boosting systems, which enabled a relevant engine downsizing.
Ford Grand C-Max demo vehicle - Technical Content
FIAT 500X MT6 FWD with 1.6l Diesel Engine
Ford Grand C-Max demo vehicle with 1.0Methane Engine & P2-mHEV