The article presents the problem solution of control of a cluster of gas wells with different productive characteristics. The mathematical model of operation of wells which products are collected into a single flowline is considered. The multidimensional extreme problem is solved on the basis on this mathematical model to optimize the technological mode of the well cluster and the gas-gathering system as a single system. As a part of the oil and gas condensate fields of the Yamalo-Nenets Autonomous District, the gas deposits developed by Gazprom Neft PJSC are characterized by cluster well placement. Rational hydrocarbon production systems are designed by the organization of operational management and optimization of operation of the gas cluster wells. Equipping wells with telemetry and remote-control systems requires the development of mathematical software and the high-speed models capable to control wells in real time. The optimization of the well cluster operation is difficult because the control of one well inevitably causes a change in the mode of operation of all other wells in the well cluster. Well shutdown may occur as a result of its self-kill if the bottom-hole gas velocity is below the critical value. Another reason is the hydrate formation if a well does not reach the optimum temperature due to its low flow rate and the permafrost presence. The upper limit on the flow rate limitation is determined by the maximum allowed pressure drawdown. The mathematical model containing a system of equations that describes the well cluster operation is proposed. The obtained calculation algorithms for parameters of the well cluster allow minimizing the loss of reservoir energy in the system “reservoir – well – gas gathering system” to ensure the flow rate of each well in a strictly specified range and maintain the parameters of the system in optimal condition.
Keywords: MATHEMATICAL MODEL, MULTIDIMENSIONAL EXTREME PROBLEM, OBJECTIVE FUNCTION, GAS WELLS OPERATION OPTIMIZATION.