Identification and Robust Control of an Experimental Servo Motor

Abstract

In this work, the design of a robust controller for an experimental laboratory-scale position control system based on a DC motor drive as well as the corresponding identification and robust stability analysis are presented. In order to carry out the robust design procedure, firstly, a classic closed-loop identification technique is applied and then, the parameterization by internal model control (IMC) is used. The model uncertainty was evaluated by means of parametric and global representation. For the latter case, an interesting discussion about the conservativeness of this description is presented by means of the comparison between the uncertainty disk and the critical perturbation radius approaches. Finally, conclusions about the performance of the experimental system with the robust controller are discussed by means of comparative graphics of the controlled variable and the Nyquist stability margin as a robustness measurement.