Abstract

Background and Introduction: The proposed control law is designed to provide fast reference tracking with minimal overshoot and to minimize the effect of unknown nonlinearities and external disturbances.

Methods: In this work, an enhanced composite nonlinear feedback technique using adaptive control is developed for a nonlinear delayed system subjected to input saturation and exogenous disturbances. It ensures that the plant response is not affected by adverse effect of actuator saturation, unknown time delay and unknown nonlinearities/ disturbances. The analysis of stability is done by Lyapunov-Krasovskii functional that guarantees asymptotical stability.

Results: The proposed control law is validated by its implementation on exothermic chemical reactor. MATLAB figures are provided to compare the results.

Conclusion: The simulation results of the proposed controller are compared with the conventional composite nonlinear feedback control which illustrates the efficiency of the proposed controller.

Keywords: Nonlinear delayed system, input saturation, composite nonlinear feedback control, adaptive control, linear matrix inequality, lyapunov-krasovskii analysis.