"Pseudo" Direct Drive Electrical Machines With Alternative Winding Configurations

The integration of a magnetic gear and a brushless permanent magnet machine to realize a “pseudo” direct drive (PDD) with alternative winding configurations is investigated. It is shown topologies which facilitate the winding process and achieve a more robust stator construction exist. Comparisons with conventional PDD topologies which are essentially equipped with concentric windings have shown that similar efficiencies can be achieved, albeit at the expense of reduced torque densities. Furthermore, analysis of the magnetic forces exhibited by a pole piece has shown that both the average and dynamic forces are significantly affected by the rated load condition, exacerbating the radial forces.