Disturbance rejection control of turbofan engine large envelope with multiple performance indicators constraints

To provide prescribed multiple performances for turbofan engine subject to state disturbances, a robust nonlinear controller is designed based on the large-envelope nonlinear parameter-varying (NPV) model in this paper. Firstly, the influence of state disturbances on the turbofan system is regarded as the parameter uncertainty in the system parameters. Then, constraints on performance indicators are translated into constraints on state error. Next the exponential decay function is designed to limit the state error, so that the system can meet the prescribed performance indicators. Finally, the solvability conditions of the controller are obtained via sum of squares (SOS) technique, and the stability of the closed-loop system is proved by the Lyapunov stability theory. Simulation results on a two-axis turbofan engine show that the proposed control method can effectively suppress state disturbances on the turbofan engine and the control system meets the given performance index constraints such as adjustment time, overshoot, and steady-state error. © 2024 South China University of Technology. All rights reserved.