ABSTRACT In this paper, we present a quasi‐3D multi‐material topology optimisation (MMTO) method to improve the torque density of a surface permanent magnet (SPM) motor. In the proposed MMTO approach, the 3D optimisation model is segmented into multiple layers along the axis of rotation. The material distributions and magnetisation directions of the permanent magnets in each layer are simultaneously optimised. Furthermore, we propose a hybrid quasi‐3D MMTO method that incorporates parameter optimisation to refine the height and radius of each layer. The resulting 3D‐optimised SPM motor exhibits higher torque density than both the reference model and its 2D‐optimised counterpart, as it directly accounts for 3D magnetic characteristics, including end effects.
Kinoshita et al. (Thu,) studied this question.