Abstract: Systems and methods for electric machine cooling. The electric machine, in one example, includes a cooling assembly with a coolant inlet that flows coolant into a first sealed chamber that is formed around end windings on a first axial side of the electric machine. The cooling assembly further includes a coolant outlet that receives coolant from a second sealed chamber that is formed around end windings on a second axial side of the electric machine and a coolant channel extending through a stator core and in fluidic communication with the coolant inlet and the coolant outlet.

Abstract: Systems and methods for electric machine cooling. The electric machine, in one example, includes a rotor that includes an outer circumferential surface with one or more spiral grooves, a stator that circumferentially surrounds the rotor and includes end windings, and an air passage radially extending from the stator to an air gap between the stator and the rotor. The electric machine further includes a cooling assembly configured to spray a coolant towards the end windings.

Abstract: Methods and systems for cooling an electric motor are provided. An electric motor system, in one example, comprises a rotor with a plurality of axial air conduits, a first balancing plate positioned on a first axial side of the rotor, the first balancing plate comprising an inlet air duct and an outlet air duct, and a second balancing plate positioned on a second axial side of the rotor, the second balancing plate comprising an inlet air duct and an outlet air duct. In the electric motor system, the inlet air duct in the first balancing plate is radially offset from the inlet air duct in the second balancing plate.

Abstract: An electric motor and inverter assembly and a method of assembly therefor, the electric motor and inverter assembly having a motor housing portion, a DC bus bar for electrically connecting a DC power source to an inverter power module where the DC bus bar is mounted on the housing portion, and a cooling channel disposed in between the housing portion and the DC bus bar for cooling the DC bus bar.

Abstract: Methods and systems are provided for an electric axle in a vehicle. An electric axle includes an electric motor having a stator and a rotor, a coolant manifold mounted to a first end plate of the rotor, the first end plate opposite a second end plate distal to the coolant manifold, wherein the coolant manifold is configured to flow coolant to rotor coolant lines extending axially through the rotor, and a spray ring comprising coolant lines coupled to the coolant manifold, wherein coolant flowing from the coolant manifold to the spray ring flows in a direction angled to an axial direction, wherein the spray ring is positioned circumferentially about axial stator end windings and configured to spray coolant onto an outer diameter of the end windings, wherein the first end plate and the second end plate are configured to spray coolant onto an inner diameter of the end windings.

Abstract: Systems and methods for electric motor cooling. The cooling system, in one example, includes a sealing ring coupled to or formed in a stator and including a flange that axially extends outward from an axial side of the stator. The cooling system further includes a first sealing sleeve with a first sealing interface that is formed between the sealing sleeve and a motor housing and a second sealing interface that is formed between the sealing sleeve and the flange, where a cavity is formed between the sealing sleeve and the sealing ring in which a stator end winding is at least partially immersed in a coolant.

Abstract: Systems for removing excess coolant oil and air from a radial air gap between a stator and a rotor of an electric motor are provided. In one example, the systems may include a ring covering the radial air gap, the ring configured to route coolant out of the radial air gap via one or more channels.

Abstract: Systems and methods for cooling an electric motor in an electric drive unit are provided. In one example, the electric motor includes a stator and an inverter power module positioned within a motor housing. The inverter power module forms an interface with a peripheral surface of an outer section of stator laminations of the stator, and the stator laminations include a plurality of cutouts forming axially extending oil ducts.

Abstract: The present document relates to an electric drive unit, comprising: a stator configured to produce a stator magnetic field, at least a first rotor including first rotor windings, the first rotor windings for instance including multi-phase windings, and at least a first inverter electrically connected with the first rotor windings and configured to produce an electric current in the first rotor windings for producing a first rotor magnetic field. The stator magnetic field is configured to interact with the first rotor magnetic field to exert a torque on the first rotor. The present document further relates to a method of operating the electric drive unit.

Abstract: Various methods and systems are provided for a system for cooling an electric motor that includes a rotor shaft rotatably mounted inside a motor housing, a lamination stack integrally connected to the rotor shaft, an encoder-end balance plate integrally connected to a first end of the lamination stack and a first end of the rotor shaft, an output-end balance plate integrally connected to a second end of the lamination stack and a second end of the rotor shaft, an oil supply coupled to the output-end balance plate and the rotor shaft. A closed-looped coolant pathway is formed between the transmission, the rotor shaft, the encoder-end balance plate, the lamination stack, and the output-end balance plate.

Abstract: Various systems and methods are provided for an electric motor of a vehicle, and particularly to an electric motor including a coolant spray ring. In one example, a spray ring for an electric motor comprises an outer circumferential surface including a plurality of axial grooves, an inner circumferential surface including a plurality of nozzle orifices in fluidic communication with the plurality of axial grooves, and a plurality of nozzle guide surfaces formed through the spray ring and extending from the plurality of axial grooves to the plurality of nozzle orifices in a direction toward a central opening of the spray ring.

Abstract: Methods and systems are provided for operating an electric motor including multiple rotor and stator sections. In one example, a system may include the multiple rotor sections configured to be mechanically coupled and decoupled from each other concurrently with multiple stator sections configured to be electrically coupled and decoupled from each other, within certain regimes of operation of the electric motor.

Abstract: The present disclosure relates to a transmission for a vehicle having a power source, the transmission comprising: an input member for receiving power from the power source; an output member for outputting power to at least one component of the vehicle; at least one power split gear set having a plurality of members and operatively connected between said input member and said output member; an electromagnetic variator having a stator, an outer rotor and an inner rotor; wherein the inner rotor is at least partially received in the outer rotor and the electromagnetic variator is configured to provide variable torque transmission ratios between the outer rotor and inner rotor; and wherein said first and second rotors are each operatively connectable to different ones of said members of said power split gear set and are each operatively connectable to the input member to be driven thereby.

Abstract: Systems for removing excess coolant oil and air from a radial air gap between a stator and a rotor of an electric motor are provided. In one example, the systems may include a ring covering the radial air gap, the ring configured to route coolant out of the radial air gap via one or more channels.

Abstract: Methods and systems are provided for operating an electric motor including multiple rotor and stator sections. In one example, a system may include the multiple rotor sections configured to be mechanically coupled and decoupled from each other concurrently with multiple stator sections configured to be electrically coupled and decoupled from each other, within certain regimes of operation of the electric motor.

Abstract: Systems are provided for an electric motor. In one example, a rotor assembly of the electric motor includes a shaft, a lubricant distributor inserted into the shaft, the lubricant distributor comprising a first section comprising a plurality of first nozzles and a second section comprising a plurality of second nozzles, the lubricant distributor further comprising an overflow portion arranged between the first and second sections, and a stationary lance positioned adjacent to the first section of the lubricant distributor, the lance comprising a plurality of radial nozzles. The rotor assembly controls coolant flow towards the rotor and bearings, helping to decrease drag losses.

Abstract: Various methods and systems are provided for thermal management of an electric motor via a coolant flow around portions of the electric motor, where the coolant flow is disrupted by an arrangement of pin-fins. In one example, an electric motor comprises: a casing including a coolant inlet arranged opposite to a coolant outlet across a central axis of the electric motor; a stator housed within the casing and forming a plurality of pin-fins extending straight outward radially, relative to the central axis, from outer circumferential surfaces of the stator in a staggered arrangement around an entire perimeter of the stator; and a plurality of clearances formed between adjacent pin-fins of the plurality of pin-fins, the plurality of clearances adapted to flow a coolant from the coolant inlet to the coolant outlet.

Abstract: Various methods and systems are provided for a system for cooling an electric motor. The cooling system includes a primary coolant passage through a rotor shaft linked to a plurality of secondary passages though lamination stacks of a rotor configured to receive coolant at a central region of the lamination stacks.

Abstract: Various methods and systems are provided for thermal management of an electric motor via a coolant flow around portions of the electric motor, where the coolant flow is disrupted by an arrangement of pin-fins. In one example, an electric motor comprises: a casing including a coolant inlet arranged opposite to a coolant outlet across a central axis of the electric motor; a stator housed within the casing and forming a plurality of pin-fins extending straight outward radially, relative to the central axis, from outer circumferential surfaces of the stator in a staggered arrangement around an entire perimeter of the stator; and a plurality of clearances formed between adjacent pin-fins of the plurality of pin-fins, the plurality of clearances adapted to flow a coolant from the coolant inlet to the coolant outlet.

Abstract: Methods and systems are provided to cool an electric machine. In one embodiment, an electric machine includes a rotor assembly that includes a rotor shaft and a stack of rotor laminations. The rotor assembly further includes one or more nozzles designed to receive pressurized coolant from a rotor shaft coolant passage and deliver the coolant to a set of open coolant channels in the stack of rotor laminations, wherein the set open coolant channels includes outlets that are profiled to direct the coolant towards a groove in a balancing plate that is coupled to the rotor assembly.