Modified MRAC based on Lyapunov theory for improved controller efficiency

In this paper, a control algorithm is derived by cascading a feedback controller with the conventional MRAC (Model Reference Adaptive Control) based on Lyapunov theory. The stability of the derived algorithm is proved using Lyapunov stability criterion. The proposed controller is designed to control a pneumatic globe control valve and simulation is performed using MATLAB/Simulink software. The pneumatic globe control valve is further simulated with the individual PI controller and the MRAC controller, and the response of the three controllers is compared. The results show that the proposed controller has a fast and smooth convergence of the plant output with respect to the reference model, thereby showing robustness of the controller.