Robust Control of Surge Instability in a Centrifugal Compressor

This paper proposes a robust design scheme for the control of surge phenomenon appearing in a centrifugal compressor. It is known the surge instability in compressor might lead to reduce the operating efficiency and even damage the machinery while both of unstable compressor characteristics and compressor load torque are hard to exactly measure in the practical application. Based on the assumption of local sector nonlinearity for system dynamics, a robust control law is proposed to cover the system nonlinearity and uncertainties while guaranteeing the stability of system equilibrium. This is achieved by using the actuation of the driving torque and closed-couple valve. Numerical simulations are given to demonstrate the success of the proposed robust controller design. KeywordsRobust control; Centrifugal compressor; Surge phenomenon; Compressor characteristic; Local sector nonlinearity