50 these are inserted into sheet metal, and the magnets are quite soft and there can be some settling. This may require spinning of the rotor to full speed for settling followed by taking a second step for balancing, which can be an additional process step. It depends on the composition of the magnets and the twisting that is used. We published the concept for these high-speed systems in 2019 and it took six years for the systems to appear on the market after optimisation.” The weight of the motor has become a key issue. “Just a couple of years ago we saw a lot of large, heavy vehicles on the market and now we know the vehicle weight has an impact on cost, the manufacturing footprint and comfort. This is not so much on the efficiency as regenerative energy capture helps with this, but there are increasing taxes on vehicle mass.” Axial motors Current axial flux machines (AFMs) are almost exclusively dependent on rare earth magnets. To avoid the use of those cost-intensive and increasingly scarce resources, the radial flux synchronous reluctance machine (RF-SynRM) is generally considered a sustainable, robust and overloadcapable alternative, although it brings compromises in terms of installation space and torque density. The NAFTech project at the University of Aachen in Germany is working on an axial flux synchronous reluctance machine (AFSynRM) that combines the advantages of an AFM and an RF-SynRM. “Axial flow machines are currently characterised by relatively low production volumes, manufacturing processes that are not yet fully developed, and special requirements in terms of tolerances and design processes,” says Prof Kampker. An AF-SynRM enables stable production costs and reduces dependence on volatile prices, which are prevalent with rare earth magnets. “A magnet-free motor generally also reduces material costs by up to 50%, which can strengthen the competitiveness of SMEs and lower barriers to market entry,” says Prof Kampker. UK axial motor manufacturer YASA, part of Mercedes-Benz since 2021, has brought all its production under one roof in Oxfordshire, UK. This creates a seamless manufacturing ecosystem with more automation for the intricate production processes. The lines include four new, uniquely constructed coil and bar manufacturing cells with state-of-the-art CNC coil July/August 2026 | E-Mobility Engineering YASA’s new production line (Image: YASA) Hollow wires for hairpin cooling (Image: RWTH Aachen University) Deep insight | E-motor production technology
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