One embodiment is an electric drive system including a plurality of redundant motors, wherein power generated by the plurality of motors is used to drive a rotor system comprising a rotor shaft having a plurality of rotor blades connected thereto via a swashplate; a gear box associated with the plurality of redundant motors; a cyclic actuation system for controlling an individual pitch of the rotor blades connected to the swashplate; and at least one structural element for retaining the redundant motors, the gear box, and the cyclic actuation system together as a single integrated unit.

One embodiment is an electric drive system including a plurality of redundant motors, wherein power generated by the plurality of motors is used to drive a rotor system comprising a rotor shaft having a plurality of rotor blades connected thereto via a swashplate; a gear box associated with the plurality of redundant motors; a cyclic actuation system for controlling an individual pitch of the rotor blades connected to the swashplate; and at least one structural element for retaining the redundant motors, the gear box, and the cyclic actuation system together as a single integrated unit.

An electric motor includes a housing, a shaft, a rotor, a stator, and at least one coolant supply channel. The shaft is rotatably mounted within the housing and has a longitudinal axis. The rotor is fixed to the shaft for rotation therewith. The stator is spaced apart from the rotor along the longitudinal axis of the shaft to yield at least one air gap between the stator and the rotor. The at least one coolant supply channel extends through at least one of the shaft and the stator and is configured to supply coolant flow to the at least one air gap.

An electric motor includes a housing, a shaft, a rotor, a stator, and at least one coolant supply channel. The shaft is rotatably mounted within the housing and has a longitudinal axis. The rotor is fixed to the shaft for rotation therewith. The stator is spaced apart from the rotor along the longitudinal axis of the shaft to yield at least one air gap between the stator and the rotor. The at least one coolant supply channel extends through at least one of the shaft and the stator and is configured to supply coolant flow to the at least one air gap.

A cooling system includes a first cooling loop, a second cooling loop and a heat exchanger configured to transfer heat from the first cooling loop to the second cooling loop. The first cooling loop includes a flow restrictor, an inertial separator, and a pressure relief valve cooperating to effect diversion of vapor present in the first cooling loop due to a leak between the first cooling loop and the second cooling loop.

A system and method of active endturn cooling of an electric motor of a vehicle is provided. The method comprises providing a motor having a coolant nozzle and a cam, and measuring speed, lateral acceleration, and road tilt angle of coolant due to road tilt. The method further comprises calculating coolant angle and coolant acceleration angle based on the road tilt angle and the lateral acceleration if the speed is greater than zero. The method further comprises comparing the coolant angle with a critical angle. The method further comprises calculating a first control angle and a first coolant distance based on the road tilt angle and the lateral acceleration of the vehicle if the acceleration angle is greater than the critical angle. The method further comprises determining a cam position based on the first control angle. The method further comprises moving the cam to the position to move the nozzle and compensate for the lateral acceleration such that coolant drops within a target area of the motor.

A system and method of active endturn cooling of an electric motor of a vehicle is provided. The method comprises providing a motor having a coolant nozzle and a cam, and measuring speed, lateral acceleration, and road tilt angle of coolant due to road tilt. The method further comprises calculating coolant angle and coolant acceleration angle based on the road tilt angle and the lateral acceleration if the speed is greater than zero. The method further comprises comparing the coolant angle with a critical angle. The method further comprises calculating a first control angle and a first coolant distance based on the road tilt angle and the lateral acceleration of the vehicle if the acceleration angle is greater than the critical angle. The method further comprises determining a cam position based on the first control angle. The method further comprises moving the cam to the position to move the nozzle and compensate for the lateral acceleration such that coolant drops within a target area of the motor.

A vehicle driving apparatus includes: a rotating machine; a cover covering the rotating machine and including a thick portion having a predetermined thickness in a direction of a rotation axis of the rotating machine; an oil pump attached to the cover; and a relief valve provided in the cover, and configured to discharge an oil supplied from the oil pump. The relief valve includes a cylinder room that is provided in the thick portion. The thick portion is provided with at least one cutout extending from an inner wall of the cylinder room in a direction substantially perpendicular to the rotation axis. The cover is provided with at least one rib each of which is disposed in a position opposed to a corresponding one of the at least one cutout and extends in the direction of the rotation axis.

A vehicle driving apparatus includes: a rotating machine; a cover covering the rotating machine and including a thick portion having a predetermined thickness in a direction of a rotation axis of the rotating machine; an oil pump attached to the cover; and a relief valve provided in the cover, and configured to discharge an oil supplied from the oil pump. The relief valve includes a cylinder room that is provided in the thick portion. The thick portion is provided with at least one cutout extending from an inner wall of the cylinder room in a direction substantially perpendicular to the rotation axis. The cover is provided with at least one rib each of which is disposed in a position opposed to a corresponding one of the at least one cutout and extends in the direction of the rotation axis.

A system and method of active endturn cooling of an electric motor of a vehicle is provided. The method comprises providing a motor having a coolant nozzle and a cam, and measuring speed, lateral acceleration, and road tilt angle of coolant due to road tilt. The method further comprises calculating coolant angle and coolant acceleration angle based on the road tilt angle and the lateral acceleration if the speed is greater than zero. The method further comprises comparing the coolant angle with a critical angle. The method further comprises calculating a first control angle and a first coolant distance based on the road tilt angle and the lateral acceleration of the vehicle if the acceleration angle is greater than the critical angle. The method further comprises determining a cam position based on the first control angle. The method further comprises moving the cam to the position to move the nozzle and compensate for the lateral acceleration such that coolant drops within a target area of the motor.