Studies on tracking control and disturbance attenuation for dynamical systems

Abstract

This thesis deals with the design of tracking control for several types of dynamical control systems affected by exogenous disturbances, stochastic noises, nonlinear uncertainties and input delays. The process of state and output tracking performance is attained by the utilization of Modified Repetitive Control (MRC) design whereas the disturbance attenuation performance is dealt with the incorporation of Improved-Equivalent-Input-Disturbance (IEID) estimator together with the state observer. Moreover, in order to deal the input time-varying delay for a class of stochastic control systems subject to time-varying uncertainties and external disturbances, the Extended Smith Predictor (ESP) technique is used in which the disturbance is attenuated by inserting the IEID-estimator. The two-dimensional modified repetitive control based on IEID-estimator is designed to overcome the issue of state tracking for dynamical system describing the lateral motion of vehicle with state delay. In addition, the Equivalent-Input-Disturbance and Smith Predictor (EID-SP) based control is designed for tackling the concerns of output tracking problem of fractional-order positive switched systems. Also an MRC tracking strategy for a class of switched stochastic dynamical systems based on Smith predictor and IEID-estimator is developed. Further disturbance attenuation and output tracking control performance for singular Markovian jump systems with nonlinear uncertainties, exogenous disturbances and time-varying delays are discussed. At the end, the state tracking problem is investigated for the Takagi-Sugeno fuzzy systems on the basis of MRC and equivalent-input-disturbance estimator in accordance with Cholesky decomposition method. In the aforesaid discussions, various adequate conditions for ensuring the stabilization of the addressed control systems are newline