Influence of Different Rotor Positions on the Performance of a Coreless Axial-Flux Generator

Coreless axial-flux permanent-magnet machines benefit from high torque density, low weight, high power density, and low core loss, which are due to the absence of core material in the construction of these machines. In this study, different rotor positions of a surface-mounted coreless axial-flux pm generator are investigated. In this regard, the machine is modeled using the 3D finite element method (FEM), and four various positions of the rotor are selected and then characteristics of the machine such as electromagnetic torque, electromotive force (EMF), and total harmonic distortion (THD) are compared in these different rotor positions. Also, other parameters including rotor yoke height, magnets height, and so on are considered to be constant. The comparison between the results showed that the generator has better performance when rotors are in position 3.