Unbalance vibration control for active magnetic bearing using automatic balancing system and peak-of-gain control

This paper considers unbalance vibration for five-axes active magnetic bearing systems. To suppress the vibration, the automatic balancing system (ABS) and the peak-of-gain control (PGC) are utilized. By using the ABS (the PGC), the bearing stiffness at rotational frequency is increased (decreased). In previous works, implementation methods for these have not been presented fully. Thus, in this paper, we considered the implementation of the ABS and the PGC. Moreover, in the conventional PGC, the feedback gain must be tuned according to the rotational speed of the rotor. This results in the increase of tuning cost. In order to solve this problem, the structure of the PGC is improved. Practical advantages of the PGC/ABS are demonstrated by rotational tests of a turbo molecular pump.