SOFT, VARIABLE-STRUCTURE BASED ADAPTIVE PI CONTROL FOR DC MOTOR POSITION CONTROL

Abstract

A soft variable-structure PI control is derived from the combination of genuine soft, variable-structure control and PI control. In a similar way, sliding, adaptive PI control is proposed on the basis of sliding-mode control. These new controls are termed adaptive PI control. They are essentially adaptive controls with a resetting mechanism. The adaptive process takes place during the transient time. The integral component governs the response during steady state. A position-control system for dc motor drives is proposed with a sliding, adaptive PI control used in the main loop for position control and a soft, variable-structure, PI control used in the minor loop for speed control. Simulation results demonstrate the adaptibility and robustness of the proposed position control system as well as the adaptive PI control.