Super-Twisting Algorithm for DC Motor Position Control via Disturbance Observer

This paper develops a Super-Twisting Algorithm controller via a nonlinear disturbance observer for a DC motor system subject to matched and unmatched uncertainties. The proposed controller is based upon a novel Nonlinear Disturbance Observer structure which uses the concept of total disturbance estimation in order to estimate simultaneously the matched and the unmatched uncertainties in the system. This estimation is incorporated then in a composite observer based controller where the stability analysis is given. Simulations results illustrate the effectiveness of the proposed controller compared to other some existing control designs and show its advantages in terms of disturbance rejection, nominal performance recovery and chattering reduction.