Robust Optimal Design of SPMSM Considering Manufacturing Tolerances of Permanent Magnets

Servo motors are widely used in systems that require high speed, high precision, and accurate position control. One of the critical aspects of servo motor design is the minimization of cogging torque to reduce motor vibration and noise. To achieve this, surface permanent magnet synchronous motors (SPMSMs) are commonly employed. However, manufacturing tolerances that arise during the production process of servo motors can significantly affect performance. In particular, variations in cogging torque caused by permanent magnet manufacturing tolerances can lead to motor vibration and noise, negatively impacting system stability. Therefore, robust optimization design is essential to suppress cogging torque variations and ensure system stability. This paper presents a robust optimization design for SPMSMs to mitigate the cogging torque variations caused by permanent magnet manufacturing tolerances. First, experiments and the finite element method (FEM) were used to analyze cogging torque while considering the manufacturing tolerances of permanent magnets. Subsequently, robust optimization was performed using the Taguchi method based on the design of experiments (DOE).