Robust Control for Uncertain Linear System Subject to Input Saturation

Abstract EN

A robust control scheme using composite nonlinear feedback (CNF) technology is proposed to improve tracking control performance for the uncertain linear system with input saturation and unknown external disturbances.

A disturbance observer is presented to estimate the unknown disturbance generated by a linear exogenous system.

The designed gain matrix of the disturbance observer is determined by solving linear matrix inequalities (LMIs).

Based on the output of the designed disturbance observer, a robust CNF controller including a linear feedback control item and a nonlinear item is developed to follow the desired tracking signals.

The linear feedback controller is designed using LMIs and the stability of the closed-loop system is proved via rigorous Lyapunov analysis.

Finally, the extensive simulation results are presented to illustrate the effectiveness of the proposed control scheme.