Is this the technology for the future?
A highly integrated electric wheel drive for the City Car of tomorrow. It’s been developed by Schaeffler Technologies (known as Schaeffler Gruppe in Germany) they are a privately owned manufacturer of rolling and ball bearings for automotive, aerospace and industrial use.
This innovative electric drive system will be on display in a city vehicle created in cooperation with Ford and based on the Fiesta.
The Fiesta is driven using two Schaeffler E-Wheel Drives that are installed at the rear. All components required for the drive, braking, and safety, like the electric motor, power electronics, controller, brake, and cooling system are all housed inside the wheel rim.
The E-Wheel Drive power output rates at 40 kW per unit with a continuous output of 33 kW per unit. The wheel hub drive is liquid-cooled and has a total weight of 53 Kg’s, which is about 45 Kg’s more than a conventional wheel. All the components are inside a 16-inch wheel rim, which means that any complex wiring inside the vehicle can be eliminated.
Because all the technology sits inside the wheel rim, vehicle manufacturers could rethink the city car minus some of the old space restrictions. It could be a key factor for new vehicle concepts and automobile platforms for tomorrow. Electric vehicles used in urban environments, which may become obligatory in many densely populated cities, could look to the wheel hub drive to make previously unheard-of space savings a real possibility.
The Fiesta E-Wheel Drive development vehicle designed in close cooperation with Ford Research & Advanced Engineering Europe has been through a fully packed testing schedule including a Scandinavian winter. The test drives have clearly shown that the behaviour of the test vehicle in terms of comfort and safety has remained at the same level, despite the higher wheel-sprung weight compared to the conventional basic vehicle.
We have read reports saying that the Fiesta E-Wheel Drive displays extraordinary dynamics and in addition to regulating the stability of the driving dynamics, the two wheel hub drives also allow what’s called torque vectoring. We think that means the selective distribution of the torque to each wheel. Other benefits with the E-Wheel Drive provide significant advantages in terms of manoeuvrability, driving dynamics, and active safety in addition to the extra space.
Will this be the silver bullet or just another innovation in a group of many? Well it should play a significant role for the future. An electric wheel hub drive has the potential to become an important technology and a valuable addition to the range of drives that, from a global point of view, will continue to be governed by increasingly electrified drive trains.