LEVITATION AND MULTI-MODE VIBRATION CONTROL OF A FLEXIBLE ROTOR

This paper presents a new modeling method and a control system design procedure for a flexible rotor with many elastic modes using active magnetic bearings. The purpose of our research is to let the rotor rotate passing over the 1st and the 2nd critical speeds caused by flexible modes. To achieve this, it is necessary to control motion and vibration of the flexible rotor simultaneously. The new modeling method named as Extended Reduced Order Physical Model is presented to express its motion and vibration uniformly. By using this model, a PD (Proportional -Derivative) controller to levitate the rotor and a LQ (Linear-Quadratic) controller to suppress its vibration are designed and its performance is examined.