The compact vehicle is driven using two Schaeffler E-Wheel Drives that are installed in the rear wheel arches. All components required for drive, deceleration, and driving safety in the highly-integrated wheel hub drive – like the electric motor, power electronics, controller, brake, and cooling system – are installed inside the wheel rim.
They boast technical key data of 40 kW per drive, and a continuous output of 2 x 33 kW. When viewed as a traditional reading, this equates to 110 and 90 horsepower, respectively. The liquid-cooled wheel hub drive, which is in its second (Beta) stage of development, also delivers up to 700 Nm of torque.
In comparison to the first-generation (Alpha) wheel hub drive, which was first exhibited in Schaeffler’s Opel Corsa-based Schaeffler Hybrid concept car in 2010, the E-Wheel Drive Beta thus features an output increase of one-third, as well as 75% more torque. The electrical voltage of the high-voltage drive is 360 – 420 V.
The highly-integrated wheel hub drive has a total weight of 53 kilograms, so the weight increase compared to a conventional wheel with a wheel bearing and brake is 45 kilograms. It has a 16-liter design envelope, which is housed inside a 16-inch wheel rim.
The highly-integrated wheel hub drive outweighs its Alpha-generation predecessor, which still featured power electronics installed in the vehicle, by an additional six kilograms.
Schaeffler’s E-Wheel Drive is now also part of a research project that is listed by the Federal Ministry of Economics and Technology – and is already being displayed in impressive fashion in the Fiesta E-Wheel Drive.
[source: Green Car Congress]
“The B-segment vehicle serves as a pre-production model. However, wheel hub drives have to be integrated into new vehicle concepts in order to demonstrate their strengths to the full,” explains Prof. Peter Gutzmer, Member of the Executive Board and CTO at Schaeffler, in his assessment of the drive technology innovation during the “auto, motor und sport” congress: “Thanks to this highly-integrated wheel hub drive, we can now re-think the city car without restrictions. It will be a key factor in new vehicle concepts and automobile platforms in the future. For electric vehicles used in urban environments, which may become obligatory in many densely populated areas, the wheel hub drive makes previously unheard-of space savings possible. In these new vehicle concepts, all components that are relevant for propulsion, braking, and driving safety are housed inside the wheel. The vehicle platform therefore provides maximum space for passengers, luggage, and for the battery, electronics, and communication systems. And vehicle manufacturers can use this as a basis for a range of different body designs. Automobile manufacture originally started in just the same way.”