The improved high speed electric motor

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A high speed, brushless, DC motor has a rotor comprising a solid rare earth magnet core magnetized diametrically. The rotor includes a sleeve surrounding the magnet core to radially constrain the core during high speed rotation thereof. The sleeve extends axially in both directions from the core to form a hollow shaft for the rotor. The sleeve is formed of non-magnetic, low electrical conductivity material. Control circuitry is provided including an electronic inverter of a predetermined rating, the control circuitry including means to maintain substantially constant power through the range of motor speeds from a base speed to a maximum speed while maintaining a power factor close to 1.