Development of control strategies for petroleum separation and pumping systems

Abstract

The modern control techniques are driven to maximize the performance of operational continuous plants. This technology is rather developed with several available commercial solutions, for instance, PID controller. However, some control processes of the oil industry, such as flow separation systems, that have to carry out the reservoir level control, must be considered under operation within stability band, and not only for holding the operational set point stability. Such problem must be treated no longer as an automation problem, but as a control one, in that the main focus is minimizing the control effort, that is, it is to diminish the actuator's interventions, allowing that the continuous process has the higher lifetime as possible. For this kind of process, the development of a new technology is still incipient. The purpose of this research is to study smart controllers that hold automatically the liquid level around the set point in submarine separators for oil wells, not considering the oscillations of the control signal within the admitted stability band. This controller focuses on the stabilization of the speed control signal of an electrical submersible pump - which is installed on the separator and that sends the separated oil to the petroleum platform -, in order to minimize the amount of pump's acceleration and deceleration activation ramps, thus enlarging its lifespan and therefore reducing operational costs, without preventing the liquid-gas separation efficiency. (AU)