The Study of Optimal Controller Design for Magnetic Bearings System

• Main Authors: Lu Yuh-Ching, 盧郁青
• Other Authors: Chou Cang-Leh
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/14500252846142545869

碩士 === 中正理工學院 === 兵器系統工程研究所 === 87 === The design and research of the controllers used in magnetic bearings are discussed in this thesis. Due to the progresses in modern technology, we need faster revolving rate, lower vibration, higher precision and lower friction machines in industry. Therefore, the controlling technology of the active magnetic bearing not only enables the rotating shaft to float in the air, but also provides many advantages such as higher speed, more stability, no-noise and lower power consumption compared to traditional bearings. Two major parts are included in this thesis. The motion equations for this magnetic bearing system are derived in part one. The controllers used in the magnetic bearings are designed in part two. Originally, because magnetic bearing is an unstable system, we need a controller to keep its balance. The design of linear quadratic regulator (LQR) is used in this thesis. PD controller on two active magnetic bearings of the rigid-rotor system is set-up. Adjusting the bearing stiffness and damping by the optimal control method lets the whole system work very well. It does reduce the deviation of the rotational axis of the magnetic bearing and get better control results by choosing the LQR weighting matrixs Qc and Rc appropriately.