Improved Recursive-gradient-based Model-free Adaptive Control Algorithm

In this paper, the improved recursive-gradient-based model-free adaptive control algorithm is investigated where a momentum term is added in the form of parameter’s change at the previous moment. It is that not only the direction but also the amplitude of the gradient descent are considered, the convergence speed of the algorithm is accelerated and therefore the dynamic performance of the system is enhanced. By rigorous mathematical induction, the convergence of output tracking error and the BIBO stability of the closed-loop system are proved. Simulation results demonstrate the effectiveness and feasibility of the proposed algorithm.