Acceleration Control Design for Turbofan Aero-engines Based on A Switching Control Strategy

This paper studies the acceleration control design problem for the turbofan aero-engines. This is a multi-objective control design problem. The key point of the acceleration control scheme is to achieve the trade-off between temperature safety protection and acceleration response performance. To this end, a novel switching control strategy is proposed. In the proposed scheme, the acceleration procedure is divided into three stages, namely the acceleration stage, the safety protection stage, and the steady state stage. Three sub-controllers are designed corresponding to the three stages. Then, a switching logic is designed to activate the sub-controllers in turn to achieve the multi-objective. Compared to the existing works, filter for the acceleration signal and leading compensation for the measured high pressure turbine (HPT) outlet total temperature are taken into account. Control design thus becomes complicated. The proposed strategy is based on the equilibrium manifold expansion (EME) model. This nonlinear model gives a more accurate dynamical description for the aero-engines. Finally, a case study based on the nonlinear component-level (NCL) model of a two-spool turbofan engine is given. Simulation results verify the effectiveness of the proposed switching control strategy, and indicate that the proposed scheme brings improvement on both safety and transient performance.