Method and apparatus for controlling a walking beam pump

摘要

Method for controlling an electric drive motor coupled to a reciprocating mechanical system such as an oil well walking beam pump by inserting a pair of power-off pulses in a reciprocation period of the pump motor energization cycle, with one pulse in a top-of-cycle region and the other pulse in a bottom-of-cycle region to reduce rod stress and motor electrical power consumption and increase pump displacement and efficiency.