TOP DRIVE DRILLING SYSTEM AND OTHER APPLICATIONS USING A LOW SPEED DIRECT DRIVE AC MOTOR

摘要

A top drive drilling system that includes an electric motor for producing sufficient torque to rotate a drill string and a drill bit during drilling operations; a stator assembly having stator packs that are longitudinally spaced to form radially directed channels for the movement of ambient or cooling air; a rotor assembly having rotor packs that are also longitudinally spaced to form channels for movement of ambient or cooling air; a pulse width modulated variable speed drive for generating a signal to drive the electric motor at the desired speed of the drill bit, which avoids the need for speed reduction equipment; and a cooling system to pass air through the radially directed channels in the stator and rotor assemblies.