Analysis of Geostationary Spacecraft Solar Arrays Degradation From Solar Proton Flares

摘要

This paper describes the radiation-induced degradation of silicon-based solar arrays of the SESAT and the YAMAL commercial telecommunications spacecraft, operating in the geostationary Earth orbit since April 18, 2000 and September 6, 1999, respectively. A comparative study of the predicted and the observed behavior in the current generated by their photovoltaic arrays contained in this paper has revealed a significant impact of large solar flares on their performance in 2000-2001. On the basis of such data as duration, scale and spectral composition of the proton fluence registered during these solar flares, an assessment of the radiation-induced degradation of the photovoltaic arrays was made. The results of this work were corroborated by the downlinked telemetry data, with which monitoring of changes in the current generated by the solar arrays was performed.