Conference: The 16th Joint Conference on Magnetism and Magnetic Materials and Intermag (2025 Joint MMM-Intermag)
Authors: Jae-Hyun Kim, Yun-Jae Won, Soo-Hwan Park, Myung-Seop Lim
DOI:
Cogging torque in surface-mounted permanent magnet synchronous motors (SPMSMs) is an important design criterion for applications such as reaction force actuators in steer-by-wire systems and robotics. Ideally, the cogging torque in SPMSMs can be minimized by applying a skew with an appropriate angle, considering the pole-slot combination. However, due to manufacturing tolerances (MTs), additional cogging torque harmonics may occur, which cannot be disregarded. Similarly, differences in the saturation magnetic flux density between the rolling and counter rolling directions of non-oriented electrical steel can generate additional cogging torque harmonics. In this study, we investigated the impact of the anisotropic properties of non-oriented electrical steel on cogging torque. To differentiate the additional cogging torque caused by stator and rotor MTs from that caused by the anisotropic properties of non-oriented electrical steel, the effects of stator and rotor MTs were analyzed using 2D finite element analysis (FEA). Subsequently, 2D FEA was conducted by considering the anisotropic properties of non-oriented electrical steel. This analysis results confirmed that additional cogging torque harmonics, distinct from those caused by stator and rotor MTs, were generated. Finally, a prototype was fabricated to validate the analysis results, and the analysis results were confirmed through tests and 3D FEA.