Feedback Controllers for the Simulation of Field Processes

Abstract

Summary Control systems with feedback controllers are useful in reservoir simulation because they enable the maintenance of desired operating conditions of a field. This, in turn, helps to establish the value of implementing automated mechanisms in the field, and also in determining long-term field operating strategies. A generic controller framework is constructed within a reservoir simulator that enables the usage of different kinds of controller algorithms for managing a variety of field processes. In this study, three field processes are considered. First, average pressure within a reservoir region is maintained by adjusting the voidage-replacement ratio between a group of injectors and producers. Second, control systems are used for the prevention of gas/water coning for single and multiple wells. Finally, the average temperature within a reservoir region is maintained at a critical value by controlling flow into the formation, so as to operate with the desired mobility of heavy oil. Traditional proportional, integral, derivative (PID) controllers, as well as linear and nonlinear fuzzy controllers, are considered. The advantages and disadvantages of the approaches are discussed. Tuning control systems is a difficult process in practice. Several methods for tuning the parameters of these controllers are investigated, and rule-of-thumb values are suggested in this study. Synthetic and real reservoir models are used.