Improved Analytical Model for Electromagnetic Analysis of Axial Flux Machines With Double-Sided Permanent Magnet Rotor and Coreless Stator Windings

Abstract

This paper deals with the experimental verification and electromagnetic analysis of an axial flux machine with a double-sided permanent magnet (PM) rotor and coreless stator windings, based on analytical field computation. Employing a magnetic vector potential and a 2-D analytical model, magnetic fields produced by PMs are obtained. The 3-D problem is solved by introducing a special function for the radial position. Then, the analytical solutions for back emf, electromagnetic torque, and efficiency of the PM-type axial flux machines are derived by using the magnetic field solutions and considering simple equivalent circuits. The analytical results are validated extensively by 3-D FE results. Test results such as back-emf, torque, and efficiency measurements are also presented to show the effectiveness of the analyses.