Abstract: When hydraulic actuating cylinders of aeroengine guide vane control mechanisms fail under the conditions of high speed, high temperature and variable loads, the working states of hydraulic actuating cylinders will be limited and the actual physical parameters of the system will change abruptly, which further aggravates parametric uncertainties and unmodeled disturbances and deteriorates position tracking accuracy and even makes the system unstable. To improve the control performance and fault-tolerance ability of hydraulic actuating cylinders, this paper proposes an integral robust adaptive active fault-tolerant control strategy for motion tracking control of aeroengine hydraulic actuating cylinders under fault conditions. To reduce parametric uncertainties, a composite parameter adaptive law is developed based on both parameter estimation errors and the tracking error, which can not only achieve fast convergence rates of parameters, but also improve the active fault tolerance of the system. To eliminate the remaining parametric uncertainties and external disturbances, an integral robust adaptive active fault-tolerant control method is presented, which further enhances the fault-tolerant ability and tracking accuracy of the hydraulic actuating cylinder. On basis of the Lyapunov theory, it is demonstrated that the active fault-tolerant control strategy can realize asymptotic convergence of the tracking error under external disturbances. The simulation results show that the proposed active fault-tolerant control strategy has better parameter adaptive ability and anti-disturbance ability than existing fault-tolerant control methods, and the estimated parameters can converge quickly within 7 s.

Key words: aeroengine guide vane control mechanism, hydraulic actuating cylinder, active fault-tolerant control, adaptive control, integral robust control, asymptotic convergence