Analysis Of Flywheel Disturbance Characteristics And Study Of Vibration Isolation Method

With the improvement of remote sensing satellite resolution,people put forward higher requirements on pointing accuracy and stability of satellite platform.There are some disturbance sources in the spacecraft,which are characterized by low amplitude and high frequency.These disturbances usually do not damage the structure of the spacecraft but affect the pointing accuracy and attitude stability of the payload.It is found that flywheel micro-vibration disturbance is the main source of disturbance in spacecraft.Therefore,the research on flywheel disturbance characteristics and vibration isolation method plays an outstanding role in improving the resolution of remote sensing satellite.In this paper,the micro-vibration disturbance of flywheel is studied by means of dynamic modeling,disturbance characteristic analysis and experiment.A flywheel vibration isolation method with high reliability is proposed for the disturbance characteristics of flywheel.The main work of this paper is as follows:Firstly,the supporting mode of the flywheel is simplified and modeled,and the dynamic model of the flywheel based on linear elastic support is established,and the main disturbance term of the flywheel is brought into the model as external excitation,which can effectively reflect the dynamic characteristics of the flywheel at medium and low speed.Then the strain-load inside the bearing is analyzed,the method of calculating the bearing stiffness by bearing parameters is given,and the flywheel dynamic model considering bearing vibration is further deduced.By analyzing the dynamic model of flywheel supported by linear elasticity,the expressions of natural frequencies of flywheel modes are obtained,and the excitation of flywheel mass imbalance to each mode is analyzed.Then the influence of mass imbalance of flywheel under nonlinear bearing supporting stiffness is studied and the method to improve bearing supporting stiffness is given.A method of calculating the main parameters of flywheel model based on the output harmonic disturbance of flywheel is proposed.Then the actual disturbance output of the flywheel is measured,and the correctness of the flywheel model is proved by comparing the output curve of the numerical example.Based on the analysis of single dof flywheel vibration isolation system,a vibration isolation method of series elastic support device on the bearing is proposed.Aiming at the inherent shortcomings of passive vibration isolation,an intelligent beam model based on velocity negative feedback is proposed.Through the above research,the influence of internal parameters of flywheel,the theoretical analysis of flywheel disturbance,the measurement of flywheel disturbance experiment,and the vibration isolation design of flywheel are given,which provides guidance for the production,selection,experiment and vibration isolation design of flywheel.