Evaluation of Lyapunov-Based Observer Using Differential Mean Value Theorem for Multiphase Flow Characterization

Abstract

Summary In this paper, we present two new Lyapunov-based observers for the decentralized multiphase flow measurement that are based on the interconnections between the two subsystems to precisely estimate the states of the multiphase flow at the gas refinery. Because the system is composed of two interconnected subsystems, the states of the condensate and gas subsystems were separately estimated using the differential mean value theorem (DMVT), the sliding mode observer (SMOU), and the HYSYS® simulator (Hyprotech, Ltd., Calgary, Alberta, Canada) by considering the relationship between two subsystems, designing an observer, and converting the conditions to linear matrix inequality (LMI). Using the HYSYS simulator with the real process data, we found that both the observers are capable of estimating the states with some differences in performance, and the drift flux model (DFM) is sufficient for states estimation of the multiphase flow entering the gas refinery.