Stability Analysis and Control of Rotating Stall

Abstract Issues of stability and control of rotating stall in axial flow compressor dynamics are considered. A stationary bifurcation analysis of compression system near the stall point is obtained, which shows that the stability of system can be predicted from either of two mathematical models of system, regarding the choice of state variables. If the amplitude of the first harmonic mode of rotating stall is selected as one of system states, the compression system may exhibit a pitchfork bifurcation. However, the system could have a transcritical bifurcation while the square of the amplitude of the first harmonic mode of rotating stall is one of system states. The dynamical behavior of compression system is found to be strongly dependent on the given compressor characteristic. It is observed that, to control the rotating stall, tools from stability analysis of bifurcation theory must be applied. A quadratic feedback control law is proposed, via throttle setting, to control system behavior near the stall point. Simulations illustrate the nature of the conclusions and demonstrate that the compressor characteristic significantly affect the post-stall behavior of compression systems.