ACTIVE VIBRATION CONTROL OF A MOTOR SYSTEM BY USING H-INFINITY CONTROL-THEORY

This paper considers the vibration control of a motor system which has a motor and a load connected with a flexible shaft. However, this system often generates a shaft torsional vibration. Traditional methods of treating this problem to adjust the PID controller so that the closed-loop frequency response is slower than that of the vibration mode. On the other hand, one method has already been proposed in which the vibration is suppressed by a disturbance observer. This paper proposes a new approach based on H(infinity) control theory. For comparison, a PI control system based on classical control theory also is constructed. The results of several experiments show that compared with the PI control system, the H(infinity) control system is effective in suppressing the vibration. Further, the H(infinity) controller obtained in the study consists of a PI controller and a series compensator that functions as an active vibration controller.