Design of a high speed printed circuit board coreless axial flux permanent magnet machine

The use of printed circuit board stators in coreless axial flux permanent magnet machines allows to reduce manufacturing costs and to eliminate the main drawbacks of traditional implementations using Litz wire. This work investigates the design of a coreless axial flux permanent magnet machine having printed circuit board concentrated windings. The field model of the coreless machine is reviewed to obtain closed-form equations for torque, eddy current loss and circulating currents loss are presented. Furthermore, cardinal geometrical parameters of the printed circuit board stator and the latest manufacturing possibilities are investigated, followed by the presentation of important machine design details.