Torque Analysis and Measurements of Cylindrical Air-Gap Synchronous Permanent Magnet Couplings Based on Analytical Magnetic Field Calculations

This paper presents the torque analysis and measurements of cylindrical air-gap synchronous permanent magnet couplings based on analytical magnetic field calculations. Employing a magnetic vector potential and a 2-D analytical model with two polar coordinate systems, we obtain the magnetic fields produced by permanent magnets. Then, the analytical torque solutions are derived using these magnetic field solutions and a Maxwell stress tensor method. The analytical results are validated by nonlinear 2-D and 3-D finite element results. Finally, torque measurements are presented to show the effectiveness of the analysis.