Hybrid electric motor with self aligning permanent magnet and squirrel cage dual rotors magnetically coupled with permeant magnets and bars at synchronous speed

A method for transitioning from induction operation at startup to synchronous operation of a hybrid squirrel cage/permanent magnet motor comprising:

• obtaining a hybrid squirrel cage/permanent magnet motor comprising:
• a motor housing;
• a stator fixed to the motor housing and producing a rotating stator magnetic field;
• a motor shaft rotatably connected to the motor housing and extending from at least one end of the motor housing for attachment to a load;
• a squirrel cage inner rotor rotationally fixed to the motor shaft residing coaxial with the motor shaft and comprising:
• a second rotor core;
• second electrically conductive squirrel cage bars embedded angularly spaced apart in a second exterior surface of the second rotor core;
• and
• voids creating flux barriers inside the second rotor core, the flux barriers comprising concave paths connecting interior ends of the second electrically conductive squirrel cage bars and guiding the rotating stator magnetic field through the second rotor core during synchronous operation;
• and
• an outer rotor residing between the stator and squirrel cage inner rotor and coaxial with the motor shaft and not mechanically coupled to the motor shaft, the squirrel cage inner rotor, and the stator, and comprising:
• a first rotor core;
• first electrically conductive squirrel cage bars embedded in the first rotor core;
• and
• permanent magnets on an interior surface of the first rotor core;
• providing an Alternating Current (AC) signal to the stator;
• creating a rotating stator magnetic field inductively cooperating with the hybrid squirrel cage and permanent magnet outer rotor to create torque on the hybrid squirrel cage and permanent magnet outer rotor;
• beginning rotation of the hybrid squirrel cage and permanent magnet outer rotor;
• after the hybrid squirrel cage and permanent magnet outer rotor begins to rotate, the permanent magnets of the hybrid squirrel cage and permanent magnet outer rotor creating a second rotating magnetic field cooperating with the squirrel cage inner rotor;
• accelerating the hybrid squirrel cage and permanent magnet outer rotor towards synchronous engine speed;
• near synchronous engine speed, the hybrid squirrel cage and permanent magnet outer rotor and stator combining to form a joint rotating magnetic field;
• the joint rotating magnetic field inductively cooperating with the second electrically conductive squirrel cage bars of the squirrel cage inner rotor;
• the squirrel cage inner rotor approaching synchronous engine speed;
• and
• the hybrid squirrel cage and permanent magnet outer rotor and the squirrel cage inner rotor magnetically coupling at synchronous engine speed.

A method for transitioning from induction operation at startup to synchronous operation of an inductive/permanent magnet motor comprising:

• providing an Alternating Current (AC) signal to a fixed stator;
• creating a rotating stator magnetic field inductively cooperating with an inductive and permanent magnet rotor to create torque on the inductive and permanent magnet rotor, the hybrid inductive and permanent magnet rotor comprising:
• the inductive and permanent magnet rotor residing coaxial with a motor shaft and having a first rotor core, angularly spaced apart permanent magnets embedded in the first rotor core, and inductive elements, the inductive and permanent magnet rotor not rotationally mechanically coupled to the motor shaft at any time other than parasitic mechanical rotational coupling through bearings coupling the inductive and permanent magnet rotor to the motor shaft, and the inductive and permanent magnet rotor capable of rotating independently of the motor shaft, and solely mechanically coupled to all other motor elements through the bearings;
• the rotation of the inductive and permanent magnet rotor;
• after the inductive and permanent magnet rotor begins to rotate, the permanent magnets of the inductive and permanent magnet rotor creating a second rotating magnetic field cooperating with a squirrel cage rotor, the squirrel cage rotor comprising:
• the squirrel cage rotor residing coaxial with the motor shaft and having a second rotor core, flux barriers in the second rotor core, and second squirrel cage bars embedded in the second rotor core, and the squirrel cage second rotor rotationally fixed to the motor shaft;
• accelerating the inductive and permanent magnet rotor towards synchronous engine speed;
• near synchronous engine speed, the inductive and permanent magnet rotor, and the stator, combining to form a joint rotating magnetic field;
• the joint rotating magnetic field inductively cooperating with the second squirrel cage bars of the squirrel cage second rotor;
• the squirrel cage rotor approaching synchronous engine speed;
• at synchronous speed, the inductive and permanent magnet rotor, and the squirrel cage rotor, magnetically coupling with the rotating stator magnetic field cooperating with the permanent magnets;
• and
• at synchronous speed, the flux barriers guiding the rotating stator magnetic field though the second rotor core.