Control of Self-Excited Vibration of a Rotor System With Active Gas Bearings

This paper presents an experimental study on the active control of self-excited vibrations in a rotor-bearing system supported on a pair of externally pressurized thrust bearings in the axial direction and on actively controlled journal gas bearings in the radial direction. The active journal gas bearings used are of the tilting-pad type with one traditional passive pad and two active pads with embedded piezoelectric actuators. Feedback control systems are constructed with gap sensors for measuring the vibration of the rotor, embedded piezoelectric actuators, and PID controllers. The experimental results show that the self-excited vibration can be effectively suppressed with the designed feedback control system, if the gains of the PID controllers are properly tuned.