Diagnosis Method Of Eccentric Wear Of Rod And Tube And Pump Condition Of Pumping Unit Based On Measured Electrical Parameters

At present,the rod sucker pump is still the main oil extraction method.Aiming at the shortcomings of the measured indicator diagram and the inverse demonstration power diagram,this paper has launched a comprehensive research on the inverse demonstration power diagram based on electrical parameters.On this basis,the intelligent early warning method of rod and tube eccentric wear based on the hanging point indicator diagram is studied.The intelligent diagnosis and production measurement methods of oil well working conditions based on the reverse demonstration power diagram and the downhole pump power diagram are studied.This article mainly carried out the following research:The actual crank angular velocity is expressed as a Fourier series with undetermined coefficients.Based on the theoretical calculation results and actual measurement results of the suspension displacement,the crank angular velocity optimization objective function is constructed using the principle of least squares.The immune-based particle swarm optimization algorithm is used to solve the extreme value of the objective function,and the actual motion law of the crank is fitted.Considering the influence of the system's inertial torque,an inversion model of the suspended load based on the measured motor input power is established according to the system energy balance relationship.Based on the extreme value method,the top and bottom dead center suspension loads are determined.Based on the arc transition curve,a simulation model of the suspension load near the top and bottom dead points of the inverse power diagram is established,which effectively solves the problem of the top and bottom dead center divergence of the inverse power diagram.The mechanical model and wave equation of the longitudinal vibration of the eccentrically worn rod column were established,and the pump end excitation,suspension displacement excitation and damping force excitation were comprehensively considered.The wave equation of the eccentrically worn rod column was solved based on the mode superposition method,and the rod column was simulated.The hanging point indicator diagram under partial wear.Based on the wavelet analysis,the four-layer wavelet coefficients of the suspended point load with different degrees of eccentric wear are extracted,and the total energy loss rate of wavelet is taken as the first characteristic parameter of eccentric wear.The stroke length of the loading line is determined based on the maximum value method of suspension load,and the loading line change rate is taken as the second characteristic parameter of eccentric wear of rod string.The rate of change of the loading line is regarded as the second characteristic parameter of the eccentric wear of the rod column.An early warning method for pole-column eccentric wear based on the hanging point indicator diagram is established.Taking the moment characteristics of the hanging point indicator diagram and the geometric characteristics of the downhole pump power diagram as the characteristic parameters describing the downhole working conditions,the characteristic parameter calculation model is established.Based on BP artificial neural network,the oil well condition diagnosis model is established.Based on the curvature of the pump work diagram,a calculation model for the effective displacement of the plunger and the oil well production based on the diagnosis of the opening point of the traveling valve is established.