Abstract: A high-speed rotor for an AC permanent magnet synchronous motor includes a stack of magnetically permeable rotor laminations. Each rotor lamination comprises a plurality of conductive bar slots for holding a starter winding and having openings facing outside for minimizing the flux leakage from the rotation magnetic field produced by primary windings on the stator, and magnet slots for holding permanent magnets to produce an even number of magnetic poles on the periphery of the rotor. The lamination further includes a plurality of flux barrier slots connected to the magnet slots for minimizing the flux leakage from the permanent magnets and forming bridges in a ring configuration between the conductive bar slots and the barrier slots so that the integrality of the lamination is very much enhanced, while the power loss is minimized.

Abstract: Alternating Current (A.C.) Motors are modified in such a way as to provide zero to full nameplate torque, by inserting magnetic rods into elongate control-rod-receptive channelways in the stator. By moving the rods in and out of their respective channelways the magnetic path of the stator flux will change. With the rods all the way out of the stator full nameplate torque is achieved. As the rods are inserted deeper into the stator, the output torque of the rotor will decrease proportionally to a minimum value.