Research Of Multivariate Sliding Mode Control On Aero-Engine

Aero-engine is a nonlinear multivariable system, which introduces complexity and tight coupling when it works. The thermodynamic behavior varies as ambient environment and working condition change. To obtain better equalities, modern control methods are applied in the design of aero-engine control systems. Sliding mode control(SMC) is a particular nonlinear control technique, which is appropriate for aero-engine, because its greatest advantage is the robustness against environment disturbance and variances of system parameters.In this paper, linear models CMAPSS-1 and CMAPSS-40 k of a multi-input multi-output(MIMO) civil turbofan engine are used for simulation. Based on Simulink module in Matlab software, different sliding mode control methods are tested at linear steady-state points. Linear parameter varying(LPV) control is used to create nonlinear dynamic process for verification.The constant speed reaching law, exponential and power reaching law are proposed, influence of different reaching law is compared and exponential reaching law is designed for global fast terminal SMC. The design process of fuzzy SMC, adaptive SMC and adaptive fuzzy SMC is analyzed, which proves stability by theoretical inference. On this basis, the advantages and disadvantages are studied and optimized adaptive fuzzy SMC is obtained.At last, limit management of aero-engine using SMC is researched, which is of actual engineering significance. The limit managementwith SMC uses an2H/ H?sliding coefficient synthesis method to design, and it can constrain system outputs within limiting value, making sure system has the best response effect and robustness. Compared with linear regulator, the advantages of sliding mode limit management are verified. Combining intelligent SMC with limit management, we obtain adaptive fuzzy sliding mode limit control, which has favorable control performance in linear and nonlinear simulation.