Position control of permanent magnet stepper motors using conditional servocompensators

The application of the ´conditional servo compensator´ technique to position control of a permanent magnet stepper motor is studied. This is a recent approach to the output regulation of minimum-phase non-linear systems that results in better transient performance over ´conventional´ servo compensator-based design. Global regulation results are provided for state-feedback control and semi-global results under output feedback, with regional results when the control is constrained. The simulation results show that good tracking performance is achieved, in spite of partial knowledge of the machine parameters.