Developing 48V through-the-road hybrid vehicle technology

The investment will help to further introduce advanced mild hybrid functionality to mainstream vehicles at significantly reduced cost to that of high voltage plug-in hybrid or pure EVs. The innovative electrified rear axle technology will be an important step in enabling OEMs to further improve both regulated and real world fuel economy in modern urban city driving conditions.

The objective of the two-year project is to achieve a CO₂ reduction of up to 15%, over the regulatory cycle, through the development of two through-the-road hybrid demonstrator vehicles. Integrating the electric motor within the rear axle will enable features such as low speed electric driving or e-creep, as well as electrically assisted all-wheel drive, which will deliver additional significant savings over a typical representative city drive cycle. The technology will allow a carmaker to reduce the in-use carbon dioxide emissions of such vehicles by approximately 25g/km.

CPT will lead the project and will be responsible for developing the electric motor and control system and will support their integration into the rear axle module. Provector has extensive experience in the control and management of advanced lead-carbon battery chemistry through projects such as ADEPT and its involvement with the Advanced Lead Acid Battery Consortium. Ricardo's key responsibilities within the project will be the design and analysis of the integrated 48V rear axle module, development of the supervisory vehicle control system, sub-system testing and project management support, building on its previous work on the ADEPT and ULTRAN projects. TMETC will supply the base vehicles, develop the suspension solution, and provide support for the application of the technology and overall vehicle integration and testing.

Peter Scanes, project director and senior manager responsible for vehicle OEM mild hybrid programmes, CPT, commented: “This programme will require a high level of project management and engineering cooperation. Not least in the unique application of a low voltage high temperature tolerant SRM, which has to be oil-cooled and packaged as efficiently as possible into a rear axle and suspension module complete with advanced lead-carbon battery.”

“The mass roll-out of electrification within the urban transportation fleet will require new and innovative power architectures that provide a performance, value and emissions trade-off that will be attractive to potential customers. Ricardo believes that a 48V electrified rear axle offering through-the-road hybrid performance - including significant ‘engine-off’ operation - will be highly attractive for many market segments but particularly for those that predominate in urban transportation,” added Stephen Doyle, head of the hybrid and electronic systems product group, Ricardo.

The FEVER project will run for two years and will culminate in the development of two through-the-road, 48V electrified rear axle demonstration vehicles.