Abstract: The principle of two type of passive vibration reduction of auxiliary magnetic bearing is discussed. And the principle is tested using an experimental rotor system adopting auxiliary magnetic bearing. The results show that active magnetic actuator with constant voltage provides not only stiffness but also damping which varies with the frequency of the motion of the rotor. And the additional stiffness also consists of two items, namely the static stiffness and the dynamic stiffness in which the former one is negative and the latter one is positive. While active magnetic actuator with constant current just provides the static stiffness.

Key words: Active magnetic damper, Passive vibration, Vibration reduction