A Safety Protection Control Method for Aero-Engines Based on the Switched Equilibrium Manifold Expansion Model

In this paper, we investigate the problem of safety protection control for aero-engines. Without loss of generality, we consider one safety boundary which is the over-temperature. The outlet temperature of the high-pressure turbine, T35, is considered as the protected variable. Firstly, based on the switched equilibrium manifold expansion (SEME) model, the output, namely the protected temperature is modeled as a switched function. The switching law is on the basis of a proposed performance index which measures the accuracy of the expression for the temperature. Furthermore, based on the proposed output model, we construct an ideal temperature dynamic to design the temperature protection controller for any subsystem of the SEME model. The switching temperature protection controller can avoid the over-temperature for aero-engines effectively. Then we give a condition in order to guarantee the stability and safety simultaneously when the temperature protection controller takes over the aero-engine from the speed regulation controller. Finally, the proposed method is applied to a simulation of a two-spool turbofan engine model to verify the effectiveness.