Patent 10008912 was granted and assigned to National Oilwell Varco on June, 2018 by the United States Patent and Trademark Office.
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.