Abstract: An electric motor assembly includes a rotor hub, and a rotor supported on the rotor hub. The rotor hub has first and second hub portions, and the rotor has first and second annular rotor segments supported for rotation on the respective first and second hub portions. Each of the rotor segments has a respective set of magnets spaced circumferentially therearound. The rotor hub and the rotor segments are configured so that at least one of the rotor segments moves about the axis of rotation relative to the other of the rotor segments as the rotor hub rotates. The movement of the at least one of the rotor segments is an amount that increases as the speed of the rotor hub increases to reduce back electromotive force. The movement may be due to centrifugal force, which increases as speed increases, without requiring a control system to effect the movement.

Abstract: A high frequency rotary transformer for an electrical machine includes a primary transformer component having a primary transformer winding, and a secondary transformer component having a secondary transformer winding. The primary transformer winding is configured to be coupled to a DC power source via a DC to AC converter. The secondary transformer winding is configured to be coupled to a winding of the rotor. Each of the primary and secondary transformer components are mechanically coupled to either the stator or the rotor. The secondary transformer component is configured to rotate with respect to the primary transformer component to produce a magnetic flux via the primary transformer winding and the secondary transformer winding.

Abstract: An electric motor assembly includes a stator having a first set of electrical windings. The motor assembly includes a rotor assembly rotatable about an axis of rotation and that has a rotor with first and second rotor segments. Each of the rotor segments has a respective set of magnets spaced therearound. The motor assembly has a phaser that includes a phaser actuator and a phaser gear mechanism. The phaser gear mechanism has a plurality of members. The phaser actuator and the first and second rotor segments are each operatively connected to a different respective one of the members. The phaser actuator is activatable to change an angular position of the member to which the phaser actuator is operatively connected, moving one of the rotor segments about the axis of rotation relative to the other of the rotor segments to reduce back electromotive force in the first set of stator windings.

Abstract: A stator core includes a first lamination and a second lamination. The first lamination is formed from a plurality of first segments and has a plurality of first mounting ears. The second lamination is formed from a plurality of second segments and has a plurality of second mounting ears. The first lamination and the second lamination are aligned with a common axis and are rotated about the common axis such that the first lamination is not aligned with the second lamination.

Abstract: A vehicle includes a power source, a motor, and a computing device. The power source provides electrical energy to the motor, and the motor generates rotational motion from the electrical energy received. The computing device is configured to estimate a temperature of the motor in real time based at least in part on a thermal model of the motor. The thermal model includes a plurality of nodes and at least one thermal resistance. Each node represents a region of the motor and each thermal resistance represents a heat transfer path between at least two of the nodes. A method includes solving one or more energy balance equations to determine a temperature change at each node and estimating the temperature of the motor in real time based at least in part on the temperature change at each node and at least one of the thermal resistances in the thermal model.

Abstract: An interior permanent magnet machine includes a rotor having a plurality of slots. First and second slots are disposed in a first pole and the third and fourth slots are disposed in a second pole. A first barrier is defined by the first, second, third and fourth slots. The slots are configured to be symmetric relative to their respective pole axes. A first angle is defined between the first and second slots. A second angle is defined between the third and fourth slots. The first angle is configured to be sufficiently different from the second angle so that torque ripple is minimized. Thus the rotor is configured such that the angular configuration of slots in a first pole is different from the angular configuration of slots in a second pole of the rotor.

Abstract: A conductor is provided for an electric machine having an axis, a radial direction extending outward from the axis, and a tangential direction perpendicular to the radial direction. The conductor includes a solid core, having radial faces substantially perpendicular to the radial direction of the electric machine and tangential faces substantially perpendicular to the tangential direction of the electric machine. At least one tangential depression is formed on at least one of the tangential faces. The tangential depression creates a tangential void within a rectangular envelope defined by the solid core. Therefore, the surface area of the solid core is greater than the surface area of the rectangular envelope.

Abstract: An integrated rotary transformer and resolver and a motor including an integrated rotary transformer and resolver is provided. The integrated rotary transformer and resolver may include, but is not limited to, a stator having an outer surface and a plurality of slots disposed along the outer surface, a plurality of sensing coils, the plurality of sensing coils disposed in at least some of the plurality of slots, a rotor having a surface varying from a first predetermined thickness to a second predetermined thickness, and a controller electrically coupled to the plurality of sensing coils and configured to determine a position of the rotor based upon a voltage induced in each of the coils due to a relative thickness of the rotor opposed to the respective sensing coil.

Abstract: A powertrain includes a first electric motor, a second electric motor and a transmission. The first electric motor includes an interchangeable winding set to provide the required power for the specific propulsion configuration utilized to propel the vehicle, i.e., a hybrid propulsion configuration or a full electric propulsion configuration. The transmission is operable in different powerflows to support operation of the powertrain in either of the hybrid propulsion configuration or the full electric propulsion configuration. The same powertrain may be used for either the hybrid propulsion configuration or the full electric propulsion configuration by switching the specific winding set installed into the first electric motor.

Abstract: A multi-filar conductor for an electric machine includes a first solid core and a second solid core. The first and second solid cores directly contact each other along a bare interface. An insulation layer surrounds the first and second solid cores. However, the insulation layer does not pass through the bare interface, such that there is no insulation between the first solid core and the second solid core.

Abstract: Systems and methods are provided for an automotive drive system using an absolute position sensor for field-oriented control of an induction motor. An automotive drive system comprises an induction motor having a rotor, and a position sensor coupled to the induction motor. The position sensor is configured to sense an absolute angular position of the rotor. A processor may be coupled to the position sensor and configured to determine a relative angular position of the rotor based on a difference between the absolute angular position and an initial angular position obtained when the induction motor is started. A controller may be coupled to the induction motor and the processor and configured to provide field-oriented control of the induction motor based on the relative angular position of the rotor.

Abstract: Method and systems for testing an electric motor are provided. A switching circuit coupled to the motor is operated in a first mode causing current to flow through the motor such that the motor is actuated with near zero torque. A magnitude of the current is repeatedly adjusted between first and second values. The current flow through the motor is monitored.

Abstract: A stator core includes a first lamination and a second lamination. The first lamination is formed from a plurality of first segments and has a plurality of first mounting ears. The second lamination is formed from a plurality of second segments and has a plurality of second mounting ears. The first lamination and the second lamination are aligned with a common axis and are rotated about the common axis such that the first lamination is not aligned with the second lamination.

Abstract: A method of manufacturing a stator core is disclosed. The method includes advancing a blank at each of a plurality of press cycles to form a segment at each of the press cycles and shaping the segments. Shaping the segments further includes activating a tooth punch, activating a mounting-ear punch, and activating an joint punch. The method also includes separating the segments from the blank.

Abstract: A conducting wire for a stator of an electric machine includes a cross section having a first side, a second side, a third side and a fourth side. The third side and the fourth side are parallel with each other, with the first side and the second side extending between the third side and the fourth side. The first side and the second side each define a concave depression.

Abstract: An electric motor assembly includes a rotor hub, and a rotor supported on the rotor hub. The rotor hub has first and second hub portions, and the rotor has first and second annular rotor segments supported for rotation on the respective first and second hub portions. Each of the rotor segments has a respective set of magnets spaced circumferentially therearound. The rotor hub and the rotor segments are configured so that at least one of the rotor segments moves about the axis of rotation relative to the other of the rotor segments as the rotor hub rotates. The movement of the at least one of the rotor segments is an amount that increases as the speed of the rotor hub increases to reduce back electromotive force. The movement may be due to centrifugal force, which increases as speed increases, without requiring a control system to effect the movement.

Abstract: Methods and apparatus are provided for a limp home operational mode for an electric motor system. The method includes determining whether a resolver has failed. When the resolver has not failed, operation of the electric motor system uses resolver signals. When the resolver fails, operation of the electric motor system uses sensorless rotor position and rotor speed signals.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engageable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations. The powertrain provides multiple operating modes between the input member and the output member, including an electric-only operating mode in which the engine is off and both electric motor/generators act as motors to provide torque at the output member.

Abstract: A vehicle includes a power source, a motor, and a computing device. The power source provides electrical energy to the motor, and the motor generates rotational motion from the electrical energy received. The computing device is configured to estimate a temperature of the motor in real time based at least in part on a thermal model of the motor. The thermal model includes a plurality of nodes and at least one thermal resistance. Each node represents a region of the motor and each thermal resistance represents a heat transfer path between at least two of the nodes. A method includes solving one or more energy balance equations to determine a temperature change at each node and estimating the temperature of the motor in real time based at least in part on the temperature change at each node and at least one of the thermal resistances in the thermal model.

Abstract: A rotor assembly is assembled by providing an elongated rectangular strip of material having a first edge and a second edge defining a width, cutting the elongated rectangular strip to form a first patterned strip having a first side corresponding to the first edge, winding the first patterned strip portion around the perimeter of the rotor core such that the first edge is adjacent to the perimeter and the patterned strip portion forms a continuous laminated ring structure. Two laminated ring structures can be cut from a single strip, thereby reducing waste material and forming a strong structure.