Contribution on AC bar windings losses reduction for a high frequency and high performance machine for aeronautical application

摘要

This paper concerns the design of a high efficiency and high torque density machine developed for a direct-drive aircraft application. Minimizing the active material in electrical machines can be achieved by attaining higher electric frequencies (> 1.5 kHz). The increasing global losses need to be addressed and minimized as the heat exchange surfaces are limited. Higher slot fill factor allows reducing the active materials (i.e. shorter tooth) and then minimizing the iron loss. Bar-wound winding shows several advantages such as reduced end-winding volume and loss. Aluminium solid conductors are in this work identified to be an intriguing solution for the given specifications. The higher resistivity reduce its vulnerability to eddy currents linked phenomena. Furthermore, aluminium powder alloys such as AlSi10Mg are nowadays widely employed in additive manufacturing and their mass density is about three times less than copper.