Theoretical study and simulation of the operation processes of plunger units with linear electric submersible pump (LESP), presented by Rosneft Oil Company, showed that there is a maximum permissible value of the plunger speed, above which the pump cylinder filling factor (CFF) decreases due to increase of the released gas volume, which should be considered when choosing LESP operation mode to enable effective operation of the unit at low-yield wells. Rosneft Oil Company have developed a method to calculate the optimum plunger speed in the suction stroke that can be applied to develop an algorithm for linear drive control, which will improve the efficiency of submersible linear drive plunger units, as well as increase fluid flow rate when equipping low production wells with the following units. An important advantage of applying the optimization of the plunger movement algorithm based on the developed method is the reduction of costs related to complications in the unit operation. There were obtained the characteristics of LESP operation on the basis of analytical solution of presented equations for determination of CFF, pressure at the pump inlet and speed of LESP plunger. On the basis of the analytical solution of the equations it has been established that the pump cylinder filling efficiency depends on the plunger speed as well as on the volume of gas entering the pump. The performed analytical analysis of the dynamics of changes in the cylinder filling factor at different plunger speeds and the share of gas entering the cylinder has confirmed the expediency of the optimization of the linear drive control algorithm. The presented method for calculating the actual flow rate of the LESP is based on determining the extremum of the parabolic function of the dependence of the flow rate on the plunger velocity.
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