Two years ago when Williams F1 was preparing for the 2009 season it bought a small company named Automotive Hybrid Power Ltd in order to co-develop its KERS system. The company renamed as Williams Hybrid Power and the kinetic energy storage system that it designed may never raced in Formula 1 but it now faces a much wider potential of various uses. The first one is the hybrid powertrain of the new Porsche GT3R Hybrid.---



When KERS first announced a lot of concepts were discussed. The most popular were batteries and flywheels with only the former seeing any action. The implementation of a flywheel in order to assist an internal combustion engine is a difficult problem, apart from the crude use of a clutch the most known system is the Torotrak CVT, where a continuously variable gearbox links the flywheel with the transmission. This system may be functional and effective but the CVT introduces some significant losses and the packaging isn't very flexible.



WHP invested on flywheels but in a new and very innovative way to incorporate a flywheel in a hybrid powertrain. Instead of using the flywheel simply as a kinetic energy storage device by constructing it with magnetic properties it behaves like an electric motor/generator.

As you can see from the image above the core of the system is a composite rotor impregnated with metallic particles that are added as a powder in the resin in order to form a Halbach Array. This makes a very lightweight rotor (a metallic magnet would have been very heavy) that can gather inertia by spinning in very high revs. The case is also relatively light and the rotor spins in vacuum, thus minimizing aerodynamic losses and the need for cooling. Magnetic losses are also very low because the isolated particles do not induce eddy currents. The efficiency of the flywheel as a system is near 99% and it can be placed wherever suits the optimum weight distribution. Instead of mechanical link to the transmission, only simple wiring is needed.

WHP system can be applied to a variety of uses, from motorsport to wind turbines or public transport. An interesting fact is that WHP have worked with British Nuclear Fuels and Urenco for this flywheel system using the experience that these companies designing uranium enrichment centrifuges.

Williams Hybrid Power website: http://www.williamshybridpower.com