Field of the Invention
The present application relates generally to electrical machines including, but not limited to electrical motors and electrical generators and more particularly, but not by way of limitation to electrical machines that are co-axially arranged with a magnetic gear.
History of the Related Art
Electrical machines have been utilized for a variety of purposes. Typically, the cost of an electric machine is proportional to the torque with which it must interact. For applications requiring a large torque at a low speed there are two generally accepted options. First, a high speed, low torque machine could be utilized in conjunction with a mechanical gear. Second, a larger low speed, high torque direct-drive machine could be utilized. Mechanical gears are generally viewed as unattractive options as they require considerable maintenance, produce acoustic noise, and have a shorter useful life.
Magnetic gears have attracted considerable attention as a possible replacement for traditional, mechanical gears. Unlike mechanical gears, which rely on the physical interaction between teeth, magnetic gears create a gearing action through the modulated interaction between magnetic flux generated by two means of inducing magnetic flux with different pole pair counts. Magnetic gears exhibit generally contactless operation and, as such, facilitate reduced maintenance, improved reliability, decreased acoustic noise, and physical isolation between input and output shafts.