ABSTRACT
This chapter applies the adaptive integrator backstepping tools to the design of a position tracking controller for the permanent magnet stepper motor driving a mechanical load. The motor is viewed as a torque source and thus a desired torque signal is designed to ensure that the load follows the desired position trajectory. Since the developed motor torque is a function of rotor position and the electrical winding currents, a simple sinusoidal commutation strategy is utilized to restate the desired torque signal as a set of desired current trajectories. The voltage control inputs are then formulated to force the electrical winding currents to follow the desired current trajectories. That is, the electrical dynamics are taken into account through the current tracking objective, and hence the position tracking control objective is embedded inside the current tracking objective. Based on exact model knowledge of the electromechanical system and full state feedback, the position tracking controller is designed for the open loop dynamics.
