Cogging Torque Cancellation Method by Periodic Boundary Symmetric Permanent Magnet Arrangement with Multiplying Waves for Axial Gap Motors

This paper proposes a method to reduce cogging torque by designing the permanent magnet shape of a single axial gap motor.This motor has a structure in which the rotor rotates opposite the stator and is capable of achieving both a flat structure and high torque density, but it has the problem of generating cogging torque, which causes noise and vibration.Previously, the authors proposed a multiplication wave type permanent magnet and confirmed that it is useful for reducing cogging torque.Based on this, in this study, we aimed to cancel out each harmonic component of the cogging torque by arranging the multiplication wave type permanent magnet symmetrically at the periodic boundary.Analysis using 3D-FEM confirmed that the cogging torque was significantly reduced while maintaining the torque.