Exploring the modular stator concepts in electric machines: mechanical and manufacturing aspects

This paper investigates the mechanical behaviour and manufacturability of a circumferentially segmented stator for a FreedomCAR compliant 12-slot/10-pole IPM traction motor. V-shape interlock laminations were fabricated and measured parasitic gaps (0.1 mm) were included in a transient structural model. Time varying electromagnetic surface forces at peak torque operation were post-processed into face-averaged excitations and applied to evaluate stresses, inter-segment deformation, and vibration characteristics. The results show that peak stresses remain well below the lamination yield strength, while the segmented architecture exhibits periodic opening and sliding at the interlocks. Frequency domain analysis reveals a dominant 2×fe component (~466 Hz) associated with slotting harmonics and the 12-segment circumferential periodicity, indicating potential links to vibration and acoustic behaviour. The study demonstrates a practical workflow for assessing modular stator concepts and highlights key structural considerations for segmented traction machine designs.