Surge Disturbance Suppression of AMB-Rotor Systems in Magnetically Suspension Centrifugal Compressors
Xue Han, Gang Liu, Baodong Chen, Shiqiang Zheng
Abstract
Surge is one of the main factors affecting the stability of the centrifugal compressor. This article investigates surge disturbance suppression of active magnetic bearing (AMB)-rotor systems in magnetically suspension centrifugal compressors. An active disturbance control method is adopted to make the rotor stably levitate under surge disturbance. First, the dynamic model of the magnetic bearing rotor is established and simplified into a single-channel model. Second, a third-order linear extended state observer (LESO) and a linear active disturbance rejection controller are designed. The performance analysis of the controller shows that the estimation error accumulation of the observer is bounded and the estimation errors decrease with the increase of the observer bandwidth. Furthermore, the variable differential parameter added in the differential link of the controller can flexibly adjust the system damping. A method of tuning parameters for linear active disturbance rejection control (LADRC) is proposed to suppress surge disturbance while satisfying the stability of the system. Finally, the results of the experiment demonstrate that the proposed scheme is effective in suppressing the large-scale vibration effect of the surge disturbance on the rotor, and the magnetically suspended centrifugal compressor (MSCC) can run stably with low amplitude under the modified surge and mild surge.