Magnetic drive devices, and related systems and methods
AssigneeNational Oilwell Varco, L.P.
InventorsKent R. Davey, David Cardellini, Cliff A. Swiontek
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Abstract
A magnetic drive device may comprise a stator comprising a plurality of windings for generating a first number of magnetic pole pairs and a rotor comprising a plurality of permanent magnets for generating a second number of magnetic pole pairs that differs from the first number of magnetic pole pairs. The magnetic drive device may further comprise a plurality of free-spinning interpole elements disposed within an air gap between the stator and the rotor. The interpole elements may produce a magnetomotive force and harmonically couple the magnetic pole pairs of the stator with the magnet pole pairs of the rotor.
Claims27
A magnetic drive device comprising:
- a stator comprising a plurality of windings for generating a first number of magnetic pole pairs;
- a rotor comprising a plurality of permanent magnets for generating a second number of magnetic pole pairs that differs from the first number of magnetic pole pairs;
- and
- a plurality of magnetized interpole elements disposed within an air gap between the stator and the rotor,
- wherein each magnetized interpole element of the plurality of magnetized interpole elements is configured to individually rotate about an axis of rotation respectively defined by each magnetized interpole element to produce a magnetomotive force and harmonically modulate the magnetic pole pairs of the stator with the magnetic pole pairs of the rotor.
A magnetic drive device comprising:
- a stator comprising a plurality of pole change windings for generating a first number of magnetic pole pairs, wherein the pole change windings are configured to change the generated first number of magnetic pole pairs;
- a rotor comprising a plurality of permanent magnets for generating a second number of magnetic pole pairs that differs from the first number of magnetic pole pairs;
- and
- a plurality of interpole elements positioned in an air gap between the stator and the rotor, wherein a size of the interpole elements and a circumferential spacing between adjacent interpole elements varies for at least some of the plurality of interpole elements so as to harmonically couple the magnetic pole pairs of the stator with the magnetic pole pairs of the rotor for each generated first number of magnetic pole pairs.
A method of varying a speed of a magnetic drive device, the method comprising:
- adjusting a number of magnetic pole pairs generated by a stator;
- harmonically coupling the magnetic pole pairs generated by the stator with magnetic pole pairs of a rotor for at least two differing numbers of magnetic pole pairs of the stator from the adjusting,
- wherein the harmonically coupling comprises individually rotating about a respective axis of rotation a plurality of magnetized interpole elements disposed within an air gap between the stator and the rotor.
Dependencies are inferred from the claim text.