Velocity control of a brushed DC-motor driven by a DC to DC buck power converter

This paper is concerned with velocity control of a brushed DC-motor when actuated using a DC to DC Buck power converter. We propose a controller which is proven to be asymptotically stable as long as the DC power supply can provide the necessary voltages at the converter inductor and capacitor. Our control scheme is the simplest controller proposed in the literature until now with a formal stability proof for this control problem. Moreover, the required number of computations are small and they are simple. Linear proportional-integral (PI) actions are used to regulate the motor electric current, the motor velocity and the converter capacitor voltage. This is important since it provides robustness to the control scheme and linear PI controllers are the main components used in the successful strategy used in industry to control brushed DC-motors. These results are tested experimentally in a setup constructed by the authors.