Current Control of Stepper Motors Using Position Measurements Only

Abstract

In the previous chapters, voltage level controllers for stepper motors were presented which utilized full state feedback, i.e., position, velocity, and phase currents. Often, it is desirable to eliminate velocity sensors and thus reduce the cost and complexity of the overall system. Furthermore, the current dynamics are fast compared to the mechanical dynamics which permits us to neglect them in control design. In this chapter, current-level controllers for stepper motors are derived that utilize only the rotor position (i.e., the output) for feedback and maintain robustness to uncertainties and unmeasurable disturbances occurring in the mechanical dynamics [148]. The control design methodology is based on the results in Chap. 6.