Robust microprocessor control of a brushless D.C. motor driving variable inertia loads

Abstract

The integration of mechanical and electrical elements into a mechatronic design is facilitated, if unwanted interaction is minimized by means of a suitable control technique. The example of a brushless d.c. motor servomechanism, in which speed and position control must be robust in the presence of mechanical load changes, is considered. Torque pulsations are also removed by a software current controller. It is shown that, while classical control is adequate for current and speed controls, a nonlinear (sliding mode) controller is necessary for position. The design process is outlined and experimental results are shown.