Research on Nonlinear Control of AC Active Magnetic Bearings

Abstract:

For the five degree-of-freedom (5-DOF) AC active magnetic bearing (AMB), which is a multivariable, nonlinear and strongly coupled system, conventional single-variable controller cannot meet the control requirements. Based on the state space model of 5-DOF AC AMB and direct feedback linearization, the equations of coordinate transform and nonlinear state feedback can be simplified into differentiating output equations, which achieves the input-output linearization of 5-DOF AC AMB system. Then, the system can be decoupled into five independent 2-order linear subsystems and realizes the completely decoupling of 5-DOF. Finally, the internal model control (IMC) method is employed to synthesize the subsystems, in order to avoid the performance deteriorated due to the model error and external disturbance. The results of simulation example demonstrate that this decoupling control strategy can realize not only the dynamic decoupling of 5-DOF AC AMB, but also the good dynamic/static performance and robustness.

• Periodical: Advanced Materials Research (Volumes 562-564)
• Pages: 968-974
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.562-564.968
• Online since: August 2012
• Authors: De Hong Zhu, Rong Xu, Li Hu Lu, Hai Juan Liu
• Keywords: Active Magnetic Bearing (AMB), DOF, Internal Model Control, Mathematical Models

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