Characteristic And Attenuation Method Research On The Disturbance Behavior Of Sun-tracking Solar Array

A sun-tracking solar array consists of one or several solar panels and a driving mechanism.The drive mechanism rotates the solar panels to keep them towards the direction of the sun all the time to continuously generate electricity for satellite operation.Sun-tracking solar array is an indispensable energy system for high-power satellites,especially for laser communication satellites,however,the speed and driving torque of the driving mechanism is fluctuant during the process of rotation,which will cause the vibration of the high-inertia flexible solar array.Micro-vibration of satellite,as the combined effects of driving mechanism reaction force and solar array vibration on satellite body,will affect the attitude stability and positioning accuracy of the satellite and thereby reduce the performance of the payload on the satellite.Therefore,research on the micro-vibration problem caused by sun-tracking solar arrays is crucial for improving the performance of spacecraft payloads.In this study,the disturbance characteristics of sun-tracking solar arrays,the influence of micro-vibration on spacecraft,and the disturbance suppression methods are systematically and deeply studied through theoretical analysis,numerical simulation,and ground test.The main contents are as follows:1.Vibration disturbance characteristics of the sun-tracking solar array were studied by building theoretical models and simulation analysis.First,built the dynamic model of SADA by linearizing the electromagnetic torque and that of the solar array by using the Lagrange equation;obtained the theoretical model of the disturbance torque of the sun-tracking solar array by analyzing the dynamic models of SADA and solar array simultaneously through the force;simulated the disturbance torque of the sun-tracking solar array by Matlab/Simulink software,then the disturbance characteristics are obtained by analyzing the simulation results.2.Micro-vibration of the whole satellite was analyzed by integrated modeling.Besides the disturbance characteristics model,continue to build model independently for finite element model and the attitude control link of the whole satellite and then integrate them,an integrated model of the whole satellite was obtained,with a whole chain from the disturbance source to the bit error rate index of the laser communication terminal.Using this integrated model,the effect of micro-vibration caused by the suntracking solar array on the payload performance can be evaluated at the system level of the whole satellite.3.A solar array simulator that can simulate the dynamic characteristics of the solar array was designed by analyzing the characteristics of a typical multi-fold solar array with SADA connecting rods.The micro-interference force/torque test bench,built based on the Kistler table test bench,was used to test the disturbance torque generated by the SADA-driven solar array simulation prototype.The accuracy of the theoretical model was verified through the comparison of the test results and the simulation results.4.The micro-vibration ground test is an effective method to study the influence of the vibration source on the satellite.Therefore,the whole satellite micro-vibration ground test system was designed and built on this subject.Considering the difference between the space environment and the ground test environment,a gravity unloading system is introduced into the system to simulate the on-orbit status of the whole satellite and the sun-tracking solar array.The vibration of the payload mounting surface caused by the disturbance of the sun-tracking solar array was measured by the test system,and according to the test results of which the influence of the disturbance of the sun-tracking solar array on the laser communication terminal was further analyzed.The integrated model was verified through the comparison of test results and the simulation results of the integrated model.5.The research of vibration suppression method has always been the core issue of micro-vibration study.According to the transmission path of the micro-vibration in the satellite,the micro-vibration control of the satellite can be divided into three types:vibration source control,transmission path control,and sensitive load control.In this subject,micro-vibration suppression is achieved by innovatively controlling the vibration source,using a pure mechanical passive vibration isolator with a "double S" shaped flexural structural vibration-damping leg as the core to suppress the microvibration caused by the sun-tracking solar array.The above-mentioned microinterference force/torque test bench was used to measure and compare the disturbance torque before and after the installation of the vibration isolator.The comparison results show that the vibration isolator has a very good effect.