Additive Manufacturing of a Conformal Hybrid-Strand Concentrated Winding Topology for Minimal AC Loss in Electrical Machines

The power-density and reliability of electrical machines is ultimately limited by their ability to dissipate internally generated losses within the constraints of the temperature rating of the insulation systems and materials used. As the electrical windings are typically the dominant source of loss, their enhanced design is in the critical path to power-density improvement. Metal additive manufacturing has the potential to disrupt conventional winding design by removing restrictions on conductor profiles and topologies. In this paper, the concentrated windings of a high-speed Interior Permanent Magnet traction machine are redesigned in stages. At each stage, features to improve performance are introduced including non-uniform conductor shapes, hybrid-solid-stranded conductors and end-winding transposition, resulting in a conformal hybrid-strand concentrated winding topology yielding an overall 40 % reduction in loss over the baseline design.