Improved propulsion motor design for a twelve passenger all-electric aircraft

This paper investigates the design of a 12-seater aircraft electric propulsion motor (ProMo). The design procedures aim to improve the performance of a previously designed motor, while adding further restrictions to the electrical and thermal boundaries. The main targets are to achieve the required output power of 550 kW, low torque ripple and an efficiency higher than 97%. The proposed procedures include an optimum slot/pole combination study, investigation on the winding configuration and connection, scaling of the airgap thickness and permanent magnet (PM) thicknesses, and finally minimising of the motor volume. The electromagnetic design is performed through a finite element electromagnetic software package, whereas the thermal analysis uses a lumped parameter thermal network-based. The mechanical stress above the rated speed of 2000 rpm is also examined. The final design fulfils the design requirements and meets the electrical and thermal constraints.