Italian motorsport electronics specialist Magneti Marelli and UK high-speed flywheel specialist Flybrid Systems are collaborating to develop a new energy storage solution for Kinetic Energy Recovery Systems (KERS). The new product is targeted to be a high-power electrical storage system for hybrid racing cars capable of deep depths of discharge with no performance degradation and a long service life.
The new product—named the Flywheel Capacitor—consists of a high-speed carbon fiber flywheel incorporating Flybrid technology connected to a high-speed electric motor generator using technology from Magneti Marelli, all managed by Magneti Marelli’s control electronics.
The device works by applying to the electric motor generator the recovered electrical energy captured from the vehicle during braking events. The energy is stored into the Flywheel Capacitor by speeding up the flywheel. During the acceleration events of the vehicle, the energy stored into the flywheel capacitor is returned to the vehicle by transforming the kinetic energy of the flywheel into electrical energy via the motor generator.
The Flywheel capacitor will not use chemical battery-based energy storage systems.
The first Flywheel Capacitor to be developed will have a specification of 60 kW power and 600 kJ total storage capacity but the specification can be readily adapted to any vehicle requirements. Both partners will draw upon extensive experience with their own KERS products to deliver a working prototype in the next few months.
The electric motor and flywheel will rotate at up to 60,000 RPM and the flywheel will sit inside an evacuated chamber that includes special containment features to ensure complete safety. A small electric pump will occasionally top up the vacuum so that no regular maintenance is required.
State of the art magnetic design of the motor generator and high efficiency electronics are expected to deliver round trip storage efficiencies approaching 80%. The device has a low cooling requirement and contains no flammable materials. The complete flywheel capacitor including the associated electronics is expected to weigh just 20 kg.
This is an exciting new development that will deliver a high end product capable of exploitation in F1 but also suitable for more widespread use in motorsport. As well as offering low running costs the flywheel capacitor is a green alternative to regularly replacing batteries.—Jon Hilton, Flybrid Systems Managing Partner
The new flywheel capacitor product will be commercially available from both Magneti Marelli and Flybrid Systems. Both companies will continue to develop, manufacture and distribute their own existing KERS products—a battery-based system from Magneti Marelli and a flywheel-based system from Flybrid (earlier post).