Effect of Slot-Pole Combination on Performance of a Dual Rotor Halbach-Array Axial Flux Permanent Magnet Machine Enabled by Additively Manufactured Winding

The demand of high-performance electrical machines for challenging applications like aerospace has impelled the exploration of advanced manufacturing materials for the various machine parts. As a result, the concept of Additive Manufacturing (AM) can be utilized for fabricating the coils of the electric machine to increase slot fill factor , enable integrated thermal management, and reduce the conductor losses. This paper adopts the AM coils in a fractional-slot concentrated winding Dual-Rotor Halbach Array Axial Flux Permanent Magnet (AFPM) machine and investigates the influence of different slot-pole combinations on the losses and various other performance parameters of the machine. The analysis results are obtained by varying the conductor current density and rotor speed for machines with both the solid and hollow type conductors. The comparison of the results indicates an increasing trend in Alternating Current (AC) losses for lower slot per pole per phase (SPP) designs and lower current density. Various observations are gathered and concluded at the end.