Research On Dynamic Balance Control Method Of Beam Pumping Unit

At most of the time,The base motor of the oil field pumping unit is working in a light load operation,which not only results in low power utilization,but also seriously hinders the improvement of oil recovery efficiency.The alternating characteristics of the suspension load of the pumping unit are the main causes of this phenomenon.During the operation of the pumping unit,this kind of alternating characteristic will destroy the balance state of the related mechanism,cause the failure of some mechanism,shorten the service life of the reducer and motor,and cause the long-term destabilization of the ground oil production equipment.In order to alleviate the influence of this characteristic on pumping system,many scholars have studied how to work smoothly.It is a widely adopted method to increase the balance weight at different parts of the pumping unit and compensate the output of the motor by balancing its gravity characteristics.Reasonably solve the instability problem caused by the uneven load at the hanging point,reduce the output fluctuation of the motor as much as possible,not only can make the pumping unit run more smoothly,but also can improve the working efficiency of the motor.Starting from the load characteristics of the beam pumping unit,this paper studies the steady operation of the pumping unit in view of the fluctuation of the output shaft of the motor.After analyzing and analyzing the current status of the beam pumping unit and combining the corresponding relationship between the suspension point load and the crankshaft torque,the beam balance weight follow-up control scheme is proposed.Change the structure of the existing beam balance weight position to a single stop,adopt the form of changing the position with following the suspension point load change.The torque compensation of the balance heavy change is used to compensate the torque difference between the input and output of the crank shaft,reduce the output fluctuation of the reducer,stabilize the output of the motor,and then prolong the service life of the motor and rod,and achieve the energy saving control to a certain extent.According to the characteristics of the system,a fuzzy control method is adopted to dynamically adjust the balance on the upper end of the beam.Fuzzy control does not depend on the accurate mathematical model.It has strong practicability for the multi coupling and nonlinearity of the pumping unit system.The fuzzy controller can output the corresponding number of pulses according to the load change of the suspension point,and the position of the balance weight of the beam is updated indefinite by the absolute number of pulses.To verify the rationality and feasibility of the program,With the help of Matlab/Simulink toolbox,the dynamic simulation analysis is carried out,and the torque curve of crankshaft is obtained,which verifies the rationality of the proposed scheme theoretically.Then use the existing conditions of the laboratory,according to a certain proportion to build pumping unit model,the acquisition and analysis of data using fuzzy controller,sensor,servo system and measuring instruments,according to the variation of the power base of motor operation analysis and judgment of the proposed scheme is feasible and practical,Comparative analysis of changes in motor output power during and after the addition of a dynamic control scheme,The experimental results show that after adding the dynamic balance control scheme,the motor output power is more stable,the utilization efficiency is higher,and the power consumption is relatively low.The scheme proposed in this paper has a positive effect on the smooth operation of the motor in the traditional beam pumping unit,especially the structural stability of the oil recovery system,and can provide some reference and reference value for subsequent analysis and research.