Comparative analysis of wave winding topologies and performance characteristics in ultra-thin printed circuit board axial-flux permanent magnet machine

Axial-flux permanent magnet synchronous machines (AF-PMSM) using printed circuit board (PCB) windings are attracting interest because of an increased demand for machines with thinner geometries. A critical element in designing these machines is the choice of its PCB winding which should ensure high-performance characteristics with an efficient use of the PCB surface. However, there is a gap in the knowledge regarding the performance of different PCB topologies. The research reported here is motivated by the need to compare common wave-type PCB windings stator topologies. Accordingly, overlapping parallel wave, non-overlapping radial wave and overlapping radial wave PCB winding topologies are assessed, using finite-element analysis, and compared based on their key performance characteristics such as the generated back-electromotive forces, inductances and electromagnetic torque. The PCB winding that provides the best torque production is then chosen and manufactured. Experimental tests on the prototyped PCB AF-PMSM provide validation.