METHOD FOR CONTROLLING VALVE-TYPE ELECTRIC MOTOR Russian patent published in 2003 - IPC

FIELD: electrical engineering; oil and gas extraction industry. SUBSTANCE: method involves starting of motor rotor and its setting in rotary motion in response to emf signals in free- of-current coils of electromechanical converter armature winding. Electromechanical-converter emf signals are applied to normalizer for their conversion to logical-level digital signals that arrive at microcontroller inputs to identify switching moments in armature winding coils when it does not build up rated torque nor builds up braking torque using mathematical model of valve-type motor for the purpose. Microcontroller automatically adjusts switching advance angle to current inductances of valve-type motor and its connecting cable, as well as load current and motor speed. In this way function of controlled rotor-position sensor is implemented with the result that motor efficiency and performance characteristics are enhanced. This makes it possible to dispense with rotor-position sensor for controlling valve-type inductor motors while maintaining adequate performance characteristics of the latter. Proposed method is most effective for motors using very long cables whose length is varied within comprehensive range, such as in oil extraction, boring holes, and the like. EFFECT: enhanced functional capabilities of valve-type motor control. 1 cl, 4 dwg