Tracking Compensation Control for Nutation Mode of High-Speed Rotors with Strong Gyroscopic Effects

Due to the strong gyroscopic effects, the stable control for the nutation vibration of high-speed rotors is an important concern in magnetically suspended control moment gyros (MSCMGs). This paper addresses the two key challenges on the nutation mode control of AMB-rotor systems: using the complex coefficient representation method to obtain the accuracy nutation frequency, and proposing an adaptive tracking approach to ensure stable operations over the entire speed ranges. In order to improve the phase margin of the nutation mode, this paper proposes a nutation mode tracking compensation method based on the cross-feedback-control scheme. First, the analytical calculation for the nutation frequency of the high-speed rotor under the closed-loop condition is carried out. Then, the compensation control method using an adaptive tracking filter in the nutation control path is proposed to provide an adequate damping for the nutation mode. Simulation results show that the nutation mode tracking compensation provides a greater phase lead for the nutation mode compared to the conventional nutation mode filtering approach. Finally, the experimental results on a developed double-gimbal MSCMG prototype validate the effectiveness of the proposed method.