Design of compound motor based on Halbach inner rotor magnetic gear

The magnetic gear composite motor has a compact structure, strong reliability, and high transmission efficiency, which can make great contributions to the development of the future industry, construction engineering, aerospace, and other fields. However, there are certain problems in many aspects of the current magnetic gear. Therefore, the research on the magnetic gear composite motor is of great significance. Based on the unique alternating structure and superior magnetic field characteristics of the Halbach array, Halbach magnetization was performed on the inner rotor of the designed magnetic gear in this study, and the performance of it was compared with that of radial magnetic gear, Halbach composite motor, and radial composite motor. The experimental results show that under the Halbach magnetization method, the three-layer air gap’s strength of magnetic gear is significantly improved, and the harmonic amplitude is reduced. Accordingly, the sinusoidal property is improved; the minimum torque of this composite motor is 22.11N·m, the maximum torque is 206.41N·m, and the maximum torque is 25.88%, which is obviously higher than the radial magnetization composite motor’s maximum torque. Torque ripple is lower than that of the radial composite motor, showing that the motor runs more smoothly. The eddy current loss represents a reduction of 86W, and the performance and effects are better than those of the radial composite motor in all aspects, which proves the effectiveness of this research method.