Control of compressor surge

Abstract

This chapter presents the derivation, implementation and testing of the active surge controller developed in this book. The proposed control method employs the thrust AMB to servo control the axial clearance between the impeller tip and the static shroud. Through the modulation of the impeller axial position, the disturbances associated with the initiation of the surge instability can be counteracted, and surge can be suppressed before it reaches the full amplitude of the limit cycle. The surge controller derived in this chapter is first tested in simulation to verify the theory and assumptions needed for the design of the control algorithm, and then implemented on the experimental compressor test rig in order to validate the theory and demonstrate the effectiveness of the control method in an actual industrial compressor.