An electric machine is provided and includes a stator that includes teeth, conductive windings configured to be wound about the teeth and a rotor rotatable about the stator. The rotor includes an annular core defining first slots along a circumferential dimension and one or more second slots along the circumferential dimension between neighboring first slots, permanent magnets disposable in the first slots and cage windings disposable in the second slots.

A hybrid induction motor includes a fixed stator, an independently rotating outer rotor, and an inner rotor fixed to a motor shaft. The outer rotor is designed to have a low moment of inertia and includes angularly spaced apart first bars and permanent magnets on an inner surface of the outer rotor. The inner rotor includes angularly spaced apart second bars and interior flux barriers aligned with the second bars. The outer rotor is initially accelerated by cooperation of a rotating stator magnetic field with the first bars. As the outer rotor accelerates towards synchronous RPM, a rotating magnetic field of the permanent magnets cooperate with the second bars of the inner rotor to accelerate the inner rotor. At near synchronous speed the rotating stator magnetic field reaches through the outer rotor and into the inner rotor coupling the two rotors for efficient permanent magnet operation.

A hybrid induction motor includes a fixed stator, an independently rotating outer rotor, and an inner rotor fixed to a motor shaft. The outer rotor is designed to have a low moment of inertia and includes angularly spaced apart first bars and permanent magnets on an inner surface of the outer rotor. The inner rotor includes angularly spaced apart second bars and interior flux barriers aligned with the second bars. The outer rotor is initially accelerated by cooperation of a rotating stator magnetic field with the first bars. As the outer rotor accelerates towards synchronous RPM, a rotating magnetic field of the permanent magnets cooperate with the second bars of the inner rotor to accelerate the inner rotor. At near synchronous speed the rotating stator magnetic field reaches through the outer rotor and into the inner rotor coupling the two rotors for efficient permanent magnet operation.

A driving motor includes a rotor body that is rotatably installed inside a stator with a predetermined void therebetween and has a rotor coil wound on multiple rotator teeth. The rotor body includes: i) multiple wedges inserted between the rotor teeth of the rotor body in an axial direction and supporting the rotor coil; and ii) end coil covers mounted on both axial ends of the rotor body, respectively and connected with the wedge members. Each wedge member includes a wedge body disposed between the rotor teeth in the axial direction and connected with the end coil covers. Each wedge body is made of a metallic material having a conductivity and has an insulating layer formed on an outer surface other than both cross sections connected to the end coil covers. The end coil covers are also made of a metallic material having a conductivity and are connected with the ends of each wedge body.

A driving motor includes a rotor body that is rotatably installed inside a stator with a predetermined void therebetween and has a rotor coil wound on multiple rotator teeth. The rotor body includes: i) multiple wedges inserted between the rotor teeth of the rotor body in an axial direction and supporting the rotor coil; and ii) end coil covers mounted on both axial ends of the rotor body, respectively and connected with the wedge members. Each wedge member includes a wedge body disposed between the rotor teeth in the axial direction and connected with the end coil covers. Each wedge body is made of a metallic material having a conductivity and has an insulating layer formed on an outer surface other than both cross sections connected to the end coil covers. The end coil covers are also made of a metallic material having a conductivity and are connected with the ends of each wedge body.

A motor includes a stator having a cylindrical shape and a rotor having a cylindrical shape provided in the stator and is rotatable about a central axis of the stator and is used to drive a driving wheel of a vehicle by rotation of the rotor. The rotor has a cage and a plurality of permanent magnets provided on an inner side of the cage and disposed side by side in a circumferential direction. The cage includes a plurality of first secondary conductors extend in a radial direction. The plurality of first secondary conductors are configured such that the permanent magnet is interposed between inner parts of first secondary conductors on opposite sides in the circumferential direction.

A vehicle drive system includes a motor that has a cylindrical stator and a cylindrical rotor provided in the stator to be coaxially rotatable with a center axis of the stator and drives a front wheel of a vehicle by rotation of the rotor. The rotor has a cage section and a permanent magnet section provided on an inner circumferential side of the cage section and formed of a rare earth magnet. The vehicle drive system further includes a controller that executes a synchronous operation mode when a temperature of the permanent magnet section is lower than a predetermined temperature, and executes an asynchronous operation mode when the temperature of the permanent magnet section is equal to or higher than the predetermined temperature. In the synchronous operation mode, the rotor is rotated by using a magnetic force of the permanent magnet section.

A hybrid induction motor includes a fixed stator, an independently rotating Hybrid Permanent Magnet/squirrel Cage (HPMSC) outer rotor, and a Squirrel Cage (SC) inner rotor fixed to a motor shaft. The HPMSC rotor has spaced part permanent magnets and sets of first bars between consecutive permanent magnets. The SC rotor has groups of second bars, and slots in an outer surface between consecutive groups of the second bars. The HPMSC rotor is initially accelerated by cooperation of the stator with the first bars. The permanent magnets create a rotating magnetic field cooperating with the second bars to accelerate the SC rotor. As the HPMSC rotor accelerates towards synchronous RPM, the stator field reaches into the HPMSC rotor and cooperates with the permanent magnets to transition to synchronous operation. Salient poles created by cooperation of the permanent magnets with the slots lock the two rotors at synchronous RPM.

A hybrid induction motor includes a fixed stator, an independently rotating Hybrid Permanent Magnet/squirrel Cage (HPMSC) outer rotor, and a Squirrel Cage (SC) inner rotor fixed to a motor shaft. The HPMSC rotor has spaced part permanent magnets and sets of first bars between consecutive permanent magnets. The SC rotor has groups of second bars, and slots in an outer surface between consecutive groups of the second bars. The HPMSC rotor is initially accelerated by cooperation of the stator with the first bars. The permanent magnets create a rotating magnetic field cooperating with the second bars to accelerate the SC rotor. As the HPMSC rotor accelerates towards synchronous RPM, the stator field reaches into the HPMSC rotor and cooperates with the permanent magnets to transition to synchronous operation. Salient poles created by cooperation of the permanent magnets with the slots lock the two rotors at synchronous RPM.

A hybrid induction motor includes a fixed stator, an independently rotating outer rotor, and an inner rotor fixed to a motor shaft. In one embodiment the outer rotor includes spaced apart first bars and permanent magnets, and the inner rotor includes spaced apart second bars. In another embodiment the outer rotor includes angularly spaced apart first bars but no permanent magnets, and the inner rotor includes permanent magnets and may also include angularly spaced apart second bars. The outer rotor is initially accelerated by cooperation of a rotating stator magnetic field with the first bars. As the outer rotor accelerates towards synchronous RPM, the inner rotor is accelerated to transition to efficient synchronous operation. The outer rotor thus acts as a clutch to decouple the inner rotor from the rotating stator magnetic field at startup and to couple the inner rotor to the rotating stator magnetic field at synchronous speed.