Archie Clayton Johnson

US Patent:

51987341, Mar 30, 1993

Filed:

Mar 9, 1992

Appl. No.:

7/848624

Inventors:

Archie C. Johnson - Cody WY

Assignee:

Marathon Oil Company - Findlay OH

International Classification:

H02P 300

US Classification:

318369

Abstract:

A method for stopping the backspinning of a submersible pump motor prior to restarting the motor. A control circuit is provided which rectifies A. C. control voltage and applies the resulting D. C. voltage to an induction motor. This sets up a stationary magnetic field in the stator of the motor which creates a braking effect on the rotor. By braking the backspinning to a stop or to a speed which will not harm the motor if restarted while still backspinning, the motor can be restarted without having to wait until the downward flow of fluid causing the backspinning stops.