Control of Attitude and Vibration of a Tethered Space Solar Power Satellite

Abstract

Control algorithms are studied for the attitude motion and vibration of a tethered Space Solar Power Satellite (SSPS). Control abilities on the attitude motion of the system and on the vibration of solar panel are essential for the SSPS to accomplish the mission to collect solar power and deliver to the surface of the Earth. The SSPS is a rectangular solar panel connected a bus unit by four tethers to stabilize the system passively by use of the gravity gradient effect. The attitude motion is proposed to be control by a mass moving its position with respect to the solar panel through change of the length of tethers. Control algorithm will be studied by employing the skills of the proof–mass damper/actuators and classic and modern control algorithms are examined for the application. The vibration of the solar panel will be designed to be suppressed by actuation of tether tension. Two methods are studied for the control including the energy and wave absorbing controls, which analyze the solar panel as a continuous system and do not employ any such approximation for discretiztion of continuous system as the modal expansion method. Numerical simulator is constructed in order to implement the control algorithms to verify the validity of performances of the present control methods.