Hybrid electric motor with self aligning permanent magnet and squirrel cage rotors

A hybrid squirrel cage and permanent magnet motor comprising:

• a motor housing;
• a stator fixed to the motor housing and producing a rotating stator magnetic field at a synchronous speed;
• a motor shaft rotatably connected to the motor housing and configured for attachment to a load;
• an inner rotor rotationally fixed to the motor shaft residing coaxial with the motor shaft and having an inner rotor core and inner electrically conductive squirrel cage bars embedded in the inner rotor core, and a number N of permanent magnets embedded in the inner rotor core;
• and an outer rotor residing between the stator and inner rotor and coaxial with the motor shaft and capable of rotating independently of the motor shaft, the inner rotor, and the stator, and having an outer rotor core and outer electrically conductive squirrel cage bars embedded in the outer rotor core, the outer rotor not rotationally coupled to any motor shaft at startup, and the outer rotor is not mechanically rotationally coupled to any motor shaft, load, or power input device during any operation or speed of the motor, other than mechanical rotational coupling through bearings supporting the outer rotor;
• and the outer rotor is magnetically rotationally coupled to the Inner rotor at the synchronous speed.

A hybrid squirrel cage and permanent magnet motor comprising:

• a motor housing;
• a stator fixed to the motor housing and producing a rotating stator magnetic field at a synchronous speed;
• a motor shaft rotatably connected to the motor housing and configured for attachment to a load;
• an inner rotor rotationally fixed to the motor shaft residing coaxial with the motor shaft and having an inner rotor core, and including inner electrically conductive squirrel cage bars embedded in the inner rotor core;
• and an outer rotor residing between the stator and inner rotor and coaxial with the motor shaft and capable of rotating independently of the motor shaft and having a number N of the permanent magnets embedded in an outer rotor core and outer electrically conductive squirrel cage bars embedded in the outer rotor core, the outer rotor not rotationally coupled to any motor shaft at startup, and the outer rotor is not mechanically rotationally coupled to any motor shaft, load, or power input device during any operation or speed of the motor, other than mechanical rotational coupling through bearings supporting the outer rotor;
• and the outer rotor is magnetically rotationally coupled to the inner rotor at the synchronous speed.