Global stabilization of axial compressors using nonlinear cancellation andbackstepping designs

Issues concerning the global stabilization of axial compressors are present ed Instead of locally stabilizing the bifurcated rotating stall equilibria to avoid suddern performance drop, control schemes are proposed to globally stabilize the unstalled nominal operating paints. These are achieved by em ploying nonlinear cancellation and backstepping designs via either throttle or direct mass flow rate control if the compressor characteristic satisfie s the 'left-tilt' property. The designs not only guarantee a safe operation close to the maximum achievable pressure rise, but the bifurcated system e quilibria are also found to be stabilized due to the elimination of the jum p phenomenon. Though both throttle and direct mass flow rate control scheme s can be implemented for global stabilization, numerical simulations demons trate that direct mass flow rate control achieves better post-stall system behaviour.