Emil Motors has announced successful laboratory dynamometer testing of its initial full-scale magnet-free axial-flux induction motor research unit. The company says that this validation milestone demonstrates the feasibility of scalable, recyclable electric drive units without permanent magnets, targeting EV manufacturers and suppliers concerned with supply chain risks and rare-earth dependence.
Emil Motors reports that after detecting a stator stiffness issue in March, engineers corrected the problem by bonding stator segments and adding steel reinforcement with an axial bearing to maintain rotor air gap consistency. Early tests revealed a winding asymmetry that limited low-speed torque, traced to incorrectly transposed parallel strands. Engineers temporarily reconfigured these in series and switched the topology from star to delta, which improved high-speed torque and performance.
The test unit achieved peak torque near 270 newton-meters, sustained rotational speeds up to 7,000 RPM and shaft power close to 68 kW. To protect its only full-scale prototype, tests were limited to around 60 percent of the projected maximum torque and speed. A 16-minute high-power test confirmed thermal performance, with stable temperatures throughout. Some high-load points were not assessed due to voltage limits imposed by the interim winding configuration.
Simulation and real-world test results closely matched, prompting a set of immediate and future updates: correcting strand transposition, restoring the original star winding topology and tightening manufacturing tolerances to minimize inter-segment gaps. Planned enhancements for the next design iteration include a rotor with high-strength stainless steel layers for improved magnetic flux containment, a fully bonded rotor for increased durability and revised stator manufacturing methods to reduce cost and improve precision.
Emil Motors says it is ready to develop custom designs, scale production, and share raw test data with qualified partners under non-disclosure agreements for further evaluation.
Source: Emil Motors
