Output feedback control for stabilizable and incompletely observable nonlinear systems: jet engine stall and surge control

The problem of controlling surge and stall in jet engine compressors is of fundamental importance in preventing damage and lengthening the life of these components. In this paper, we use the mathematical model developed by Moore et al. (1986) to control these two instabilities by output feedback (only one of the three states is measurable). This problem is particularly challenging since the system is not completely observable and, hence, none of the output feedback control techniques found in the literature can be applied to recover the performance of a full state feedback controller. However, we show how to successfully solve it by using a novel output feedback approach for the stabilization of general stabilizable and incompletely observable systems. Simulation results confirm the success of this approach in solving this control problem