Practical Switching Characteristics for Minimum-Time Position Control Using a Permanent-Magnet Motor

An attempt has been made to show how well a dc permanent-magnet motor fits the requirements of the minimum-time position control problem. Using a second-order mathematical model, phase plane trajectories are studied, and an approximate solution for the switching time has been obtained in an explicit form. It has been shown that the on-line estimation of three auxiliary parameters will permit the determination of the switching time even for the very difficult problem of load variations.