Xtrac announces multiple applications for flywheel hybrids in road cars

Transmission technology specialist Xtrac says the flywheel kinetic energy recovery systems (KERS) currently being developed for Formula One could be applied to road vehicles in a number of ways.

“By providing an additional boost of power, the F1 technology is particularly relevant to the trend to fit cars with smaller engines in pursuit of better fuel efficiency and lower CO2 output,” says Xtrac technical director Adrian Moore. 

“The technical challenge with engine downsizing is compensating for the loss of engine torque and drivability, which can be restored by applying flywheel technology. It is also possible that a mechanical KERS system could be used as a range extender in a battery electric hybrid vehicle or even to power vehicle auxiliaries.

“All are potential applications of the technology, subject to the size of the flywheel, compactness of the system and vehicle packaging requirements. These are all resolvable technical issues. The intent of the KERS technology in F1 is to consider energy recovery, storage and discharge, and to demonstrate that technology in a novel and effective way.”

Complementing its work in F1, the transmission technology provider is also an active partner in a new project to develop a flywheel hybrid system for premium cars.  Xtrac forms part of a consortium supported by the UK government’s Technology Strategy Board, which recently announced funding of £23 million for 16 low carbon vehicle development projects.

The flywheel hybrid project will involve the design and development of a mechanical KERS system for use in a premium segment passenger car as an alternative solution to other hybrid systems and to prove its effectiveness and viability for production. Jaguar is leading the project, which will be carried out by a consortium made up of Flybrid Systems, Ford, Prodrive, Ricardo, Torotrak and Xtrac.

“We are very excited about being part of a consortium that has successfully secured funding to undertake one of the major UK low carbon vehicle programs,” says Peter Digby, managing director of Xtrac. “Taking a technology that has been developed for motorsport and implementing it for road vehicles in order to improve fuel economy and reduce carbon emissions so quickly after the emergence of the base technology shows how rapidly the UK motorsport industry can react. It is no surprise that a number of our consortium members are successful motorsport engineering companies who have taken up the challenge.”

Xtrac has been involved in energy efficient motorsport initiatives since 2001 and more recently has played a key role in designing, developing and integrating a mechanical KERS system for F1 with partners Flybrid and Torotrak. Xtrac’s role is to provide the toroidal continuously variable transmission (CVT) between the flywheel and the vehicle powertrain.

Given the need to develop systems in time for the 2009 season, the CVT has already undergone rigorous bench testing on Torotrak and Flybrid test rigs. The three F1 project collaborators all strongly believe that the mechanics of this system can be transferred to other technology areas including road vehicles.

A published copy of Xtrac’s latest paper on the CVT development for the flywheel KERS for F1 and its potential for road vehicles is available from the International Council for Powertrain Engineering and Management (ICPEM), at www.gpc-icpem.org.