MULTI-MODE OPTIMIZATION OF ELECTRIC SUBMERSIBLE PUMP SPEED FOR OIL WELLS

Abstract

The relevance of the research is associated with the means to increase the resource and energy efficiency of production modes of wells equipped with electric submersible pump with variable speed drive. Pump speed control is increasingly being used not only as a means of quickly responding to the complicating factors impact, but also as a tool for implementing enterprise policy in the circumstances of production quota or shortfalls compensation. The introduction of multi-mode control procedures modifies the criteria and methods for assigning base operating mode and well completion parameters. The main scope of the article is to formalize the optimization problem for the multi-mode operation schedule and electric submersible pump well completion parameters according to the daily profit criterion for the full life cycle of the submersible power unit, which determines the balance between performance, durability and energy consumption. Object of the research is the well equipped with electric submersible pump with variable speed drive. Methods: material and heat balances, hydrostatics, linearized kinetics of pressure losses in lift segments, factor analysis of failure risk, multi-parameter optimization with assessment of the responses surface using parallel computing technologies. Results and summary. The typification of operational mode diagrams and formation of the daily profit given criterion of electric submersible pump operation on its full run-life allowed formalizing the optimization problem of operating modes and well completion parameters using multi-mode operation programs. The results of computational analysis on the example of a thermobaric well model with parameters for the Middle Ob oil fields alongside with expert estimations for prices and sensitivity coefficients of the electric submersible pump resource model confirmed that, within the accepted constraints, optimal solutions deliver higher profits compared to the productivity potential schemes when implementing any multi-mode programs. The consistency of proposed optimization scheme is illustrated by the calculation of lost profits in situations when the selected control programs differ from the estimated optimal solutions for the same modes. The control of the factors of submersible unit accelerated wear and the use of the daily profit criterion makes it possible to calculate optimal solutions for any operating life-time potential without explicit information about its value.

Keywords

• models
• goal
• optimization
• multi-mode operating
• productivity potential
• run-time potential
• electric centrifugal pump
• profit
• resource and energy costs