Modular permanent-magnet electric motor

Abstract

A modular permanent-magnet electric motor assembly having a predetermined maximum power output for a submersible pump assembly, a stator having a plurality of electric coils adapted to be energized to create a magnetic field, and a rotor assembly disposed about a rotor shaft. The rotor assembly comprises a predetermined number of rotor modules sufficient to achieve the predetermined power output and a pair of bearing carriers separated by the rotor modules. Each rotor module comprises a rotor core and a plurality of magnets disposed about or otherwise associated with the rotor core. The magnetic field between the coils and the magnets causes rotation of the rotor modules, the rotor assembly, and, thus, the rotor shaft. The rotor assembly desirably also includes a protective sheath to prevent fluid from entering the rotor assembly and contacting the rotors. The predetermined number of rotor modules are installed on the shaft during the process of manufacturing the motor.

Dependencies are inferred from the claim text.