The Design, Analysis, and Verification of an Axial Flux Permanent Magnet Motor with High Torque Density

Abstract

Aiming at the defects of long axial size and low torque density of the existing radial flux permanent magnet motor, this paper proposes an axial flux permanent magnet synchronous motor (AFPMM) with a double-stator and single-rotor structure based on the design requirements of the motor for mechanical dogs’ electric drive joints. The finite element method is employed to evaluate the static magnetic field, load characteristics, and associated losses. The analysis indicates that the average magnetic flux density in the air gap reaches approximately 0.95 T, with a rated torque of around 2.72 N.m, a peak torque of 7.6 N.m, and an efficiency of approximately 87.73%. The electromagnetic torque model is developed using the Maxwell tensor method, allowing for the effects of critical structural parameters on torque to be investigated. By optimizing the design for torque density, an improvement of nearly 20% is achieved. A prototype was fabricated and tested, demonstrating good agreement between simulation and experimental results. This research introduces a novel approach for designing axial flux motors with high torque and power densities.