Active Vibration Control Of Variable Speed Tilting Flywheel

Variable Speed Tilting Flywheel(VSTF)is such an innovative device that are developed for the attitude control system of small spacecrafts.It can provide 3-DOF control torques and 2-DOF angular rate sensing owing to the advantages bringing in a spinning flex-gimbal suspension system.Because it integrates attitude-control and attitudesensitive functions,it is conducive to the development of spacecraft towards low cost,large scale,small mass and high integration.For a 3-DOF VSTF with high speed,the uneven mass distribution of the rotor,namely the unbalance,is inevitable which leads to undesirable vibration that has a bad effect for the stable and accurate operation of the rotor.Therefore,the rotor vibration control is of particularly significance.In this paper,two kinds of active vibration control methods are proposed and verified by simulation with the goal of suppressing vibration at the same frequency as speed of VSTF rotor.Firstly,according to the mechanical structure of the VSFT,a complete nonlinear dynamic equation of the VSTF system is established based on the Lagrange method,and the rotor unbalance response is modeled.The VSTF system is mechanically assembled by a multi-body dynamics software Sim Mechanics,and Simulink is used to build the simulation model,which laid a theoretical foundation and provided a simulation platform for the subsequent research.The vibration response of VSFT is analyzed based on derivation model and the Sim Mechnics model,and the effects of speed and unbalance on the tilt vibration are studied.Secondly,for the problem of active vibration control of VSTF,an unbalance compensation algorithm based on Adaptive Notch Filter(ANF)is proposed.Aiming at the failure of the traditional adaptive unbalance compensation algorithm during variable-speed rotor operation,an improved unbalance compensation algorithm based on the spatial is proposed.And using the simulation model of the VSTF,different operating conditions are designed to simulate,and the effectiveness of the designed control algorithm is verifiedFinally,an unbalance compensation algorithm different from that based on ANF is proposed.From the perspective of unbalance identification,several sets of torque are applied through the Torquer and the amplitude and phase of the correction torque are calculated using the influence coefficient method.And the correction torque is applied to the VFTF rotor by Torquer for the active vibration control of VSTF.Then,aiming at the problem that the correction torque is invalid when the rotor is running at a variable speed,an improved algorithm is proposed to change the form of the applied correction torque from frequency domain to the spatial.Simultaneously,the simulation model of VSTF is used to simulate on different operating conditions,and the effectiveness of the designed control algorithm is verified.