ASYMMETRICAL STATOR GEOMETRY DESIGN FOR THREE-PHASE MACHINES WITH DISTRIBUTED WINDING

This work focuses in detail on the flux density distribution in three-phase distributed winding machines, showing how its asymmetries in the teeth and back iron can be evaluated, and eventually compensated for. In order to achieve uniform flux density distributions, an asymmetrical stator geometry is proposed. A new set of geometrical parameters has been defined to balance the flux densities in the stator, while maintaining the same slot geometry (i.e., current density and amount of copper) and iron volume. The comparison, between a classical geometry and the proposed asymmetrical one, is carried out with the results showing the differences on the stator flux densities and the resulting torque performance. The new concept of asymmetrical design is validated for a surface mounted permanent magnet (SPM) machine as a case study. The outcomes of this work highlight the potential benefits of the presented solution with respect to the core saturation.