In some embodiments, and as shown in FIGS. 1A and 1B, one or more of the stator windings 28 are disposed around and radially outside of the rotor 24. In other words, the stator poles 29 are be disposed around and radially outside of the rotor 24. This configuration may be called an internal-rotor motor. In some embodiments (not shown in the FIGS), one or more of the stator windings 28 are disposed within the rotor 24, with the rotor 24 extending around and radially outwardly of the stator windings 28. In other words, the stator poles 29 may be disposed radially inwardly from the rotor 24 with the rotor 24 annularly surrounding the stator poles 29. This configuration may be called an external-rotor motor.

In some embodiments, and as shown in FIGS. 1A and 1B, the rotor 24 is supported upon a layer of a lubricating fluid 31, such as oil. The lubricating fluid 31 may consist of petroleum-based and/or synthetic oil and may include additives such as, for example, corrosion inhibitors, viscosity stabilizers, and/or for maintaining a specific heat capacity. With the rotor 24 supported upon the lubricating fluid 31, the rotor 24 can be moved by electromagnetic force generated by the stator windings 28 in order to supply clearance space between the rotor 24 and the stator poles 29 for the lubricating fluid 31 to occupy. In some embodiments, the rotor 24 can be moved to supply the clearance space for the lubricating fluid 31 before the rotor 24 is begun to rotate.