Modeling and disturbance suppression for spacecraft solar array systems subject to drive fluctuation

Abstract

The vibration of flexible solar array during sun-tracking drive has been one of the challenging problems in modern space technology. In this work, the vibration disturbance of the drive induced solar array vibration (DISAV) to spacecraft platform is studied. A vibration disturbance model considering both the effect of rigid-flexible coupling and the drive unstable excitation is established for a typical solar array system. It extends the traditional dynamic model of the solar array system in terms of an explicit description for the vibration disturbance. Then, an external torque compensation scheme considering both vibration suppressing and driving reliability is proposed based on a failure-protection magnetorheological actuator. The extended minimal control synthesis algorithm is adopted to achieve the compensatory torque for vibration suppression. The numerical results indicate that the energy of the vibration disturbing the spacecraft is mainly provided by the unstable drive while the flexible vibration diffuses the disturbance. And the vibration disturbance suppression should be a main task for the vibration control during the sun-tracking drive. The reliability and effectiveness of the DISAV control with a magnetorheological actuator are theoretically demonstrated from the aspect of the failure protection and active control. The maximum disturbance torque is reduced up to 68.75% during the normal sun-tracking, which demonstrates the good suppression of DISAV by the proposed torque compensation scheme.