A rotor assembly for use in a radial flux electric motor assembly includes a rotor core having a plurality of rotor poles circumferentially spaced about a central axis, wherein the rotor core includes a first end and an opposing second end. The rotor assembly further includes a plurality of core magnets alternately spaced with the plurality of rotor poles. The plurality of rotor poles define a radial aperture between each pair of circumferentially adjacent rotor poles, and each radial aperture is configured to receive at least one core magnet of the plurality of core magnets therein. A plurality of end magnets are coupled to at least one of the first end and the second end, and at least one end plate coupled to the plurality of end magnets.

A rotor assembly for use in a radial flux electric motor assembly includes a rotor core having a plurality of rotor poles circumferentially spaced about a central axis, wherein the rotor core includes a first end and an opposing second end. The rotor assembly further includes a plurality of core magnets alternately spaced with the plurality of rotor poles. The plurality of rotor poles define a radial aperture between each pair of circumferentially adjacent rotor poles, and each radial aperture is configured to receive at least one core magnet of the plurality of core magnets therein. A plurality of end magnets are coupled to at least one of the first end and the second end, and at least one end plate coupled to the plurality of end magnets.

A motor assembly includes a housing having a motor cavity. A stator is disposed within the housing. A rotor rotates within the stator and within the motor cavity about a rotational axis. A controller is coupled with the stator having a filter circuit board and a main circuit board that are interconnected at a terminal header to define a multilayer circuit board assembly. The circuit board assembly has an electrical interface and a data interface attached to at least one of the filter circuit board and the main circuit board.

A motor assembly includes a housing having a motor cavity. A stator is disposed within the housing. A rotor rotates within the stator and within the motor cavity about a rotational axis. A controller is coupled with the stator having a filter circuit board and a main circuit board that are interconnected at a terminal header to define a multilayer circuit board assembly. The circuit board assembly has an electrical interface and a data interface attached to at least one of the filter circuit board and the main circuit board.

A rotor is a consequent pole rotor. The rotor includes a first magnetic pole region functioning as a first magnetic pole, a second magnetic pole region functioning as a second magnetic pole that is a pseudo-magnetic pole, a shaft disposed in a shaft insertion hole, and a nonmagnetic member coupling the shaft to the rotor core. The nonmagnetic member includes a beam extending from the shaft to the second magnetic pole region.

A rotor is a consequent pole rotor. The rotor includes a first magnetic pole region functioning as a first magnetic pole, a second magnetic pole region functioning as a second magnetic pole that is a pseudo-magnetic pole, a shaft disposed in a shaft insertion hole, and a nonmagnetic member coupling the shaft to the rotor core. The nonmagnetic member includes a beam extending from the shaft to the second magnetic pole region.

An aircraft propulsion system comprises a propulsor an electric motor coupled to the propulsor. The electric motor comprises a surface mounted permanent magnet electric machine comprising a rotor mounted radially inward of a stator. A Motor Diameter Ratio (MDR) is defined as an inner diameter (D.sub.stator,in) of the motor stator in metres divided by an outer diameter (D.sub.stator,out) of the motor stator in metres. The MDR of the electric motor stator is within 10% of the value given by the equation:

[00001]${\mathrm{MDR}=0.83\times (\frac{\mathrm{Torq}ue}{L_{active}}\times \frac{1}{U_{\mathrm{fan},\mathrm{tip}}})}^{0.08}$ where: T is the maximum torque rating of the electric motor in kilonewton metres; L.sub.active is the active length of the motor stator in metres; and U.sub.tip is the tip speed of the propulsor at the maximum rated torque of the electric motor in metres per second.

In the described embodiments, the MDR is less than 1.

A motor includes a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, and a resolver that is configured to detect rotation of the motor rotor.

A motor includes a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, and a resolver that is configured to detect rotation of the motor rotor.

Electric motors and methods of controlling electric motors are described herein. The electric motors include a mobile component having at least one permanent magnet coupled thereto and a stator spaced apart from the mobile component. The stator includes at least one stator pole having a ferromagnetic core and a coil wrapped around the ferromagnetic core. The ferromagnetic core is naturally attracted to the at least one permanent magnet. The motors also include a magnetic position control system configured to monitor a position of the at least one permanent magnet relative to the stator and controllably deliver an electric pulse to the coil of each stator pole to generate a repulsive magnetic flux on the ferromagnetic core to cancel an attraction force between the ferromagnetic core and the at least one permanent magnet to control movement of the mobile component.