Multi-three-phase FSCW High-speed High-power-dense Inset Bread-loaf PMSM for the Electric VTOL Application

Electric motors and propellers contribute significant weight in the electric vertical take-off and landing (eVTOL). High power-density electric motors are continuously sought and being developed by eVTOL industry. This paper reviews a few standard electric motors for the eVTOL application. The current motor power density needs to be improved significantly to extend the range of eVTOLs with the limited energy density of batteries. A high torque-, and power-dense inset bread-loaf permanent magnet synchronous motor (IBLPMSM) is proposed and designed using the multi-three-phase armature winding. The nine-phase armature winding is utilised to achieve higher power density with a lower requirement of the dc-link voltage to prevent any partial discharge (PD) issues at altitude conditions. The active power-, and torque-density are achieved as high as 36 kW/kg and 96 Nm/L, respectively.