Parameter estimation and vibration control of rotor-bearing system

• Main Author: Zhou, Yu.
• Other Authors: Lim, Tau Meng
• Format: Theses and Dissertations
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Mechanical engineering::Control engineering
• Online Access: http://hdl.handle.net/10356/19870
• Institution: Nanyang Technological University

This thesis reports a practical and an effective algorithm for on-line identification of oil-film bearing coefficients and an adaptive vibration control strategy using radial magnetic bearing. Existing frequency-domain algorithms, used in identifying oil-film bearing coefficients have produced meaningful results from noisy data in comparison with the time-domain algorithm; however, they need large number of measurements and computational effort. The proposed algorithm in this report is based on the equations of motion of the bearing pedestal only. Therefore, measurement is confined to the pedestal and not the entire system. The modes of the system are continuously excited by applying multi-frequency test signals onto the rotor, and transfer function data are obtained. Results from computer simulation and experiments show that the proposed identification algorithm produces accurate and reliable estimates. The algorithm can be employed on rotor-bearing system with any degree of complexity and can be used for on-line identification, monitoring and diagnosing of rotating systems in the industries.