DC motor control with sliding mode switching modulator

In this paper a tracking problem for the position and angular speed of a DC motor is addressed. A continuous control law based on a sliding manifold approach is designed and a pulse ratio modulator is used as a switching amplifier. The combination of these two strategies guarantees robustness with respect to parameter variations and unmodeled dynamics, accurate tracking capabilities and a constant current ripple. The proposed control scheme results in a partial state feedback where only the mechanical variables of the motor are considered in the control law. The influeuce of the electrical variables on the closed loop system is also analyzed. Simulation results are presented to illustrate the effectiveness of the proposed approach