Imbalance vibration control for rotor is the main factor affecting attitude control performance for satellite using magnetically suspended control moment gyro (MSCMG). The method for adaptive imbalance vibration control for the rotor of variable-speed MSCMG with active-passive magnetic bearings is investigated in this paper. Firstly, on the basis of feedforward compensation, a rotor model for the imbalance vibration of variable-speed MSCMG with active-passive magnetic bearings is built, and the main factor affecting imbalance vibration compensation is also analyzed. Then, power amplifier parameter modifier with control switches is designed to eliminate the effects of time-varying parameters on the imbalance vibration compensation precision. The adaptive imbalance vibration control based on this modifier not only has high compensation precision, but also can control the frequency of parameter adjustment according to the compensation precision. Besides, since the passive magnetic bearing displacement stiffness of the rotor of variable-speed MSCMG with active-passive magnetic bearings cannot be obtained accurately, displacement stiffness modifier is employed. Finally, stability analysis is made on the imbalance vibration control system, and the range of rotation speed to ensure system stability is derived. Simulation results show that, imbalance vibration control method proposed in this paper can suppress the imbalance vibration of the rotor of variable-speed MSCMG with active-passive magnetic bearings effectively and has high precision.

Identification of the static mass imbalance is critical to the control of magnetically suspended rotors. A static mass imbalance identification method without using the closed-loop transfer function is proposed in this paper. Then the null displacement control of the magnetically suspended rotor is realized by using the identified static mass imbalance. Because null vibration is the control target for the rotor of a magnetically suspended control moment gyro (MSCMG) with active-passive magnetic bearings, a null vibration control method depending on the displacement stiffness is introduced. However, the displacement stiffness of the passive magnetic bearing is hard to obtain accurately. Therefore, the least mean square method is utilized to adjust the uncertain displacement stiffness adaptively according to the centroid acceleration. Simulation results show that adaptive null vibration control based on the static mass imbalance identification can remove the synchronous magnetic bearing force effectively, thus enabling the rotor of the MSCMG with active-passive magnetic bearings to rotate about its initial axis.

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Double-gimbal control moment gyros can implement the satellite attitude maneuver efficiently. In order to reduce the energy consumption of double-gimbal control moment gyros and avoid the singularity state, an attitude maneuver path planning method is proposed by using the improved Fourier basis algorithm. Considering that the choice of the Fourier coefficients is important for the Fourier basis algorithm to converge quickly, a choosing method of the initial Fourier coefficients which can reduce the computational time of the path planning algorithm notably is proposed. Moreover, an attitude-tracking feedback controller based on the Fourier basis path planning algorithm is designed to acquire robustness. Simulation results show that the proposed path planning algorithm can implement attitude maneuver path planning in shortened time. Meanwhile, the feasibility of the attitude-tracking feedback controller which is based on the above path planning algorithm is verified in terms of the low energy consumption, high attitude-tracking precision, and the safe use of double-gimbal control moment gyros.