Collaboration develops wireless charging system for race cars

The Engineer
July 26, 2011

Inductive-charging group HaloIPT has teamed up with Drayson Racing Technology to develop its wireless charging technology for high-performance cars.

Drayson Racing, which develops and races ’green’ motorsport technology, plans to market HaloIPT’s technology to the motorsport industry as a replacement for the internal combustion engine and pit stops for fuel.

The system is based on Inductive Power Transfer (IPT) wireless charging, which uses strongly coupled magnetic resonance to transfer power from a transmitting pad hidden in the road or race track to a receiving pad on an electric car.

The pad in the ground is supplied with electrical power at a current typically in the range of 5–125A. The pad is inductive so compensation using series or parallel capacitors is used to reduce the working voltages and currents in the supply circuitry.

Within the car, pick-up coils are magnetically coupled to a primary coil. Power is transferred by tuning the pick-up coil to the operating frequency of the primary coil with a series or parallel capacitor.

According to HaloIPT, the technology automatically adjusts for changes in the vertical gap between the car and the surface. It also has the ability to intelligently distribute power so that there is a consistent delivery of power at speed.

Lord Drayson, co-founder of Drayson Racing, told The Engineer: ‘With current battery technology you’re limited to about a 20-minute race in an electric car and that’s why we’re excited about induction-charging technology.’

He added that it could one day be seen on roads. ’I think that it requires very significant investment into the infrastructure for charging, but it’s a lot safer than the use of cables and it enables you to optimise energy transfer for the use of the car as a tiny storage element in a distributed energy grid. It’s an exciting part of the future.’