Impact of soft magnetic material on construction of radial flux electrical machines

Electrical machines with distributed concentrated windings are challenging the selection of the soft magnetic materials due to stator design and power conversion efficiency. A shorter magnetisation path and relatively high magnetisation frequency establish a good potential for low permeability soft magnetic materials with low power losses in the core. The focus of this article is on the analysis of a three-phase machine with laminated and iron powder cores where the concern is on the modular winding design, torque capability and stator efficiency. Different iron powder cores are compared to laminated core on basis of 2D FEA. The three-phase machine torque is compared with the conventional distributed concentrated winding, an axially distributed wave winding, and a number of circumferentially distribute wave-winding segments. According to 3D FEA, the conventional coils are preferred if the permeability of the core is low