Vision measurement-based indicator diagram generation method of beam-pumping unit

Abstract

The invention discloses a method for generating an indicator diagram of a beam-pumping unit based on visual measurement, which comprises the following steps of: acquiring a shot video of a target pumping unit, and crank external parameters and walking beam external parameters of a corresponding camera; according to the crank external parameter and the walking beam external parameter, a crank vector and a walking beam vector in a shot video are converted and fitted, then a crank angle function, a crank angular velocity function, a walking beam angle function and a walking beam linear velocity function are obtained through solving, and a polished rod displacement function and a polished rod load function are obtained through further derivation; and generating an indicator diagram according to the polish rod displacement function and the polish rod load function. According to the method, the angle functions and the corresponding angular velocity functions of the crank and the walking beam are deduced, the polished rod displacement function and the polished rod load function are calculated in combination with the electrical parameter data to generate the indicator diagram, operation is simple and clear, and an efficient and accurate indicator diagram generation scheme is provided for the beam-pumping unit.

Images