Innovative winding technology for the ultimate electric car

How do you build an engine that is half the size of current gasoline engines but delivers over 600 hp – for a car capable of over 1,000 hp? Schaeffler ELMOTEC STATOMAT delivers that solution.

In order to build these super electric car engines, Schaeffler ELMOTEC STATOMAT mastered the process of flat wire wave shaft winding. Compared with the traditional hairpin process, the flat wire wave is processed into a continuously mesh, significantly reducing the number of welds which are the primary cause of motor failure. These more compact windings lower electrical loss and result in more power and reliability.

In order to successfully wind these stators, the flat copper wires must be laid simultaneously with one another from several directions at the same time and without causing damage to the wires. Schaeffler ELMOTEC STATOMAT achieves this by utilizing twelve Franke bearing assemblies per winding machine. The bearing assemblies are aligned and move linearly to one other. "Because we receive the bearing assemblies as complete components from Franke, we avoid sum errors in the tolerances," explains Dominik Knopp, project manager at Schaeffler ELMOTEC STATOMAT. The precision in the Franke bearing assemblies makes it possible for these machines to hold the tight tolerances required.

Franke's wire race element technology allows for custom designed assemblies – materials, dimensional flexibility, and load capacity can be individually selected for optimization. Another advantage of Franke wire race bearings is their compactness and high center clearance. "With the Franke bearing assemblies, it was possible to ensure sufficient space for winding without going beyond the dimensions of the entire machine. The weight aspect is also important here: Thanks to the material aluminum in the bearing housings, we reduce the moving mass, which in turn benefits precision," explains Kai-Uwe Pahl.