Identification of Stiffness and Damping of Auto-eliminating Clearance Auxiliary Bearing Devices Based on Finite Element Method

Abstract—In order to study the dynamic supportive stiffness and damping of auto-eliminating clearance auxiliary bearing devices (ACABD) after the rotor falls, this paper proposed an identification method of stiffness and damping based on finite element method. Fist, the model of the rotor supported by ACABD and the feasibility of the method was verified by simulation. Then, the test bench of magnetic bearing system contained the ACABD was designed. And the unbalanced responses were obtained by the experiment method of unbalanced excitation. In the end, the actual supportive stiffness and damping of ACABD were obtained by the parameter identification method based on finite element method. The results indicate that during the moderation process from 500Hz to 20Hz after the drop of the rotor, the values of supportive stiffness and damping of ACABD change continually, which generally decrease with the rotational speed.