Three Phase Separators, Slug Handling, Robust Control, Process Control
Abstract
This paper presents an H_infinity approach for a three-phase gravity separator. A switching strategy is applied to chose between two controllers: one to damp oscillatory disturbances in the inflow of the separator, and one for better set-point tracking. The controller selection relies on the inflow disturbance measurement, which is unpractical or unreliable. Therefore, an H2 observer is designed to estimate the (multiphasic) inflow which in turn is utilized as the controller switching signal. The performance of the proposed strategy is compared to a traditional PI Zone controller normally used in industry. The results demonstrated that the proposed controller outperforms the performance achieved by classical PI Zone controllers allowing a good trade-off between slug attenuation and set-point tracking.
