Presented are oleophobic surface treatments for electric machines, methods for making/using such electric machines, and vehicles employing traction motors having oleophobic treatments on select “non-target” surfaces. An electric machine includes a direct-cooling thermal management system that circulates a coolant fluid to the electric machine's outer housing. A stator assembly, which is attached to the housing, includes a stator core with one or more electromagnetic windings mounted to the stator core. A rotor assembly is rotatably mounted to the hosing adjacent the stator assembly. The rotor assembly includes a rotor core with one or more magnets mounted to the rotor core and spaced across an air gap from the winding(s). Select components of the outer housing, rotor assembly, and/or stator assembly have a target surface with an oleophobic surface treatment that reduces the non-target surface's wetted area and decreases the mass of coolant fluid contacting the non-target surface.

Presented are oleophobic surface treatments for electric machines, methods for making/using such electric machines, and vehicles employing traction motors having oleophobic treatments on select “non-target” surfaces. An electric machine includes a direct-cooling thermal management system that circulates a coolant fluid to the electric machine's outer housing. A stator assembly, which is attached to the housing, includes a stator core with one or more electromagnetic windings mounted to the stator core. A rotor assembly is rotatably mounted to the hosing adjacent the stator assembly. The rotor assembly includes a rotor core with one or more magnets mounted to the rotor core and spaced across an air gap from the winding(s). Select components of the outer housing, rotor assembly, and/or stator assembly have a target surface with an oleophobic surface treatment that reduces the non-target surface's wetted area and decreases the mass of coolant fluid contacting the non-target surface.

An electrical assembly for an aeronautical turbomachine, including an electric machine configured to be disposed in a turbomachine and comprising a stator and a rotor comprising magnets, the assembly including a short-circuit detecting means, a hot air injecting means configured to draw hot air off the turbomachine at a temperature greater than the temperature of demagnetization of the magnets of the rotor, and to inject the drawn hot air onto the magnets of said rotor when the short-circuit detecting means detects the presence of a short-circuit in the electric machine, and a cool air injecting means, configured to draw cool air off the turbomachine and to inject it into an inner chamber of the turbomachine, the temperature of the cool air drawn by the cool air injecting means being less than the temperature of the hot air drawn by the hot air injecting means.

An electrical assembly for an aeronautical turbomachine, including an electric machine configured to be disposed in a turbomachine and comprising a stator and a rotor comprising magnets, the assembly including a short-circuit detecting means, a hot air injecting means configured to draw hot air off the turbomachine at a temperature greater than the temperature of demagnetization of the magnets of the rotor, and to inject the drawn hot air onto the magnets of said rotor when the short-circuit detecting means detects the presence of a short-circuit in the electric machine, and a cool air injecting means, configured to draw cool air off the turbomachine and to inject it into an inner chamber of the turbomachine, the temperature of the cool air drawn by the cool air injecting means being less than the temperature of the hot air drawn by the hot air injecting means.

A stator structure and a flat wire motor are provided. The stator structure comprises a stator core, stator windings and an avoidance layer. The stator core has an inner cylinder cavity, and a plurality of iron core slots arranged at intervals in a circumferential direction on an end face of the stator core. The iron core slot is communicated with the inner cylinder cavity via a slot opening. The stator windings have a plurality of layers of flat wire conductor wound in the iron core slots. The avoidance layer is located between the slot opening and a first layer of flat wire conductor in a radial direction of the stator core. During the operation of the flat wire motor with this stator structure, the skin effect caused by the high-frequency change of the magnetic field will act on the avoidance layer, thereby reducing the skin effect generated at the first layer of flat wire conductor, weakening the influence of the slot leakage flux on the first layer of flat wire conductor, reducing the eddy current loss of the first layer of flat wire conductor, and further reducing the eddy current loss of the whole motor, and thus achieving the technical effect of improving the motor efficiency.

A stator structure is provided and includes a plurality of first lamination layers, a plurality of second lamination layers, two third lamination layers and two oil spraying rings. The second lamination layers are sandwiched in between the first lamination layers. The second lamination layer located in the middle of the stator structure is sandwiched in between the two third lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. Another stator structure is provided and includes a plurality of first lamination layers, a second lamination layer and two oil spraying rings. The second lamination layer is sandwiched in between two first lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. By means of the arrangement of the aforesaid stator structure, the invention can effectively improve heat dissipating effect for oil cooling.

A stator structure is provided and includes a plurality of first lamination layers, a plurality of second lamination layers, two third lamination layers and two oil spraying rings. The second lamination layers are sandwiched in between the first lamination layers. The second lamination layer located in the middle of the stator structure is sandwiched in between the two third lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. Another stator structure is provided and includes a plurality of first lamination layers, a second lamination layer and two oil spraying rings. The second lamination layer is sandwiched in between two first lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. By means of the arrangement of the aforesaid stator structure, the invention can effectively improve heat dissipating effect for oil cooling.

A rotor for an electric motor includes a rotor core defining a first face, a second face, and an opening extending from the first face to the second face. The rotor also includes an output shaft received by the opening of the rotor core and a valve disposed within a passageway of the output shaft. The valve controls a flowrate of the coolant and is actuated into a fully opened position at a maximum operating temperature of the rotor. The valve includes a stem having a first end portion and a second end portion, a plug disposed at the first end portion of the stem, a valve seat disposed opposite to the plug, and a shape memory alloy actuator that expands to urge the stem of the valve and the plug away from the valve seat and into the fully opened position at the maximum operating temperature.

A rotor for an electric motor includes a rotor core defining a first face, a second face, and an opening extending from the first face to the second face. The rotor also includes an output shaft received by the opening of the rotor core and a valve disposed within a passageway of the output shaft. The valve controls a flowrate of the coolant and is actuated into a fully opened position at a maximum operating temperature of the rotor. The valve includes a stem having a first end portion and a second end portion, a plug disposed at the first end portion of the stem, a valve seat disposed opposite to the plug, and a shape memory alloy actuator that expands to urge the stem of the valve and the plug away from the valve seat and into the fully opened position at the maximum operating temperature.

An electric machine includes a housing, a stator, an oil film, and at least one first seal. The housing has an internal surface defining an internal cavity. The stator has an outer peripheral surface and is disposed within the internal cavity such that a clearance gap is defined between an outer peripheral surface and the internal surface. The oil film is disposed within the clearance gap and is in contact with the internal surface and the outer peripheral surface. The at least one first seal is disposed along a first end of the stator and is configured to retain the oil film within the clearance gap along the first end of the stator.