Mitigation of AC Winding Losses for Aircraft Propulsion Motors

In this paper, the AC copper losses are investigated and mitigated for different permanent magnet synchronous motor designs. AC copper losses can represent a substantial share of the total loss in electrical machines. In an application such as aerospace, it is more demanding to optimise all aspects of the motor design. Recently, different approaches to modelling the AC copper losses have been proposed. This paper utilises simulation software to quantify the expected AC losses from six different propulsion motor designs. The motor designs are then modified to reduce the AC winding losses. Using two-dimensional finite element analysis, the motor slot openings are modified such that an optimum design with reduced losses is achieved. The paper considers distributed, fractional slot and concentrated windings, and the results show promising reductions across these different winding configurations.