Abstract: An apparatus has a stator having a first surface and a second surface, and a plurality of rotors magnetically coupled to the stator, with a first rotor facing the first surface of the stator through a first airgap and a second rotor facing the second surface of the stator through a second airgap. First slots, each containing first conductors and separated from each other by a first tooth, are distributed along the first surface. Second slots, each containing second conductors and separated from each other by a second tooth, is distributed along the second surface, where each second tooth is separated from a close-by first tooth by a yoke area. The first teeth are interleaved with the second teeth. Windings are configured using the first conductors and the second conductors. The first rotor and the second rotor are configured to produce mechanical torque in a same direction when currents flow in the windings in an operation mode.

Abstract: An apparatus has a plurality of poles facing an air gap, and the poles are configured to generate a magnetic field in the air gap. The poles include a group of unchanged poles and a group of reversible poles, where a polarity of each reversible pole is configured to be changed during an operation mode, and after the polarity has been changed, each reversible pole and at least an adjacent unchanged pole in effect merged into one augmented pole, such that the pole number of the magnetic field in the air gap is changed.

Abstract: A device includes a stator or a rotor configured to magnetically coupled through an air gap, a plurality of slots distributed along a perimeter of the stator or rotor, a plurality of metal bars each placed into one of the plurality of slots, and an end ring having plurality of openings. Each opening is configured to receive an end of one of the metal bars, and a lock feature is configured to improve a mechanical attachment between the end ring and the metal bar.

Abstract: A method includes configuring a motor drive system with a motor/generator and a plurality of inverters coupled to the motor/generator, configuring a plurality of active harmonic planes to generate a torque on each of the active harmonic planes, and applying a harmonic plane synchronization mechanism to the plurality of active harmonic planes so that torque components and magnetizing components of currents are controlled in coordination on different active harmonic planes to output a desired torque from the motor/generator.

Abstract: An apparatus includes a stator with an inner surface and an outer surface, a plurality of rotors magnetically coupled to the stator, wherein a first rotor faces the inner surface of the stator and a second rotor faces the outer surface of the stator, and a first airgap between the inner surface of the stator and the first rotor, and a second airgap between the outer surface of the stator and the second rotor, wherein first conductors, the first airgap, and the first rotor form a first submotor, and second conductors, the second airgap, and the second rotor form a second submotor, and wherein the first submotor and the second submotor are so configured that the first rotor and the second rotor produce mechanical torques in a same direction when currents flow in the plurality of windings in an operation mode.

Abstract: A system includes a motor having a plurality of windings, a rotor and a stator magnetically coupled to the rotor, a plurality of power inverters connected to respective windings, wherein the plurality of power inverters is configured to control currents of the plurality of windings, and a controller configured to determine an injection ratio of a high-order harmonic component to a fundamental component based on a performance index, and wherein the injection ratio for a magnetizing component is different from the injection ratio for a torque component at a same harmonic frequency.

Abstract: A system includes a vehicle having an engine, a first motor mechanically coupled to a shaft of the engine, a second motor configured to provide torque to the vehicle or the engine in combination with the first motor, and a first controller coupled to at least one of the first motor and the second motor, wherein the first controller is configured such that the first motor and the second motor provide a mechanical torque to rotate the shaft of the engine before the engine is running.