@inproceedings{oai:jaxa.repo.nii.ac.jp:00007907, author = {嶋田, 貴信 and 豊田, 裕之 and 久木田, 明夫 and 廣瀬, 和之 and 前田, 良知 and 満田, 和久 and Shimada, Takanobu and Toyota, Hiroyuki and Kukita, Akio and Hirose, Kazuyuki and Maeda, Yoshitomo and Mitsuda, Kazuhisa}, book = {第32回宇宙エネルギーシンポジウム, 32nd ISAS Space Energy Symposium}, month = {Mar}, note = {第32回エネルギーシンポジウム (2013年3月1日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)), 相模原市, 神奈川県, The Space Energy Symposium (March 1, 2013. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, This paper presents the analysis results for the on-orbit performance of a solar array paddle of the X-ray astronomy satellite Suzaku. Suzaku, formerly known as ASTRO-EII, is an X-ray astronomy satellite developed by Japan Aerospace Exploration Agency (JAXA) and has been successfully making observations since its launch in July 2005. However, the current generated by its solar array was confirmed to be gradually but continuously decreasing since the middle of 2011. Consequently, we estimated the degradation of the solar array output to simulate the on-orbit environment according to the JPL prediction method in the Solar Cell Radiation Handbook using the relative damage coefficient (RDC) obtained in ground tests. The analysis results indicated that greater on-orbit degradation of the solar cell occurred compared to the predicted performance degradation under the space environment where Suzaku was exposed to the orbit. We considered that this difference in the on-orbit data and analysis results could be attributed to (i) an increase in cell temperature or (ii) radiation degradation due to solar flares. The analysis results showed that the solar array operated at a lower current point in the constant voltage region of I-V curve when the cell temperature was higher. The deterioration can be explained under the assumption that the cell temperature rose up approximate 20 C higher than the nominal operating temperature of 73 C 6 years after launch. On the other hand, it was found that the proton fluxes observed by the GOES-13 satellite increased with frequent occurrences of solar flares since 2011, which corresponded to when degradation of the Suzaku solar array performance was observed. The calculated results showed good consistency with the on-orbit deterioration under the assumption that the solar cells were irradiated with an equivalent 1-MeV electron fluence of 3.0 × 10(exp 14) particles/cm2 for one year from 6 years after launch. At present, we are examining the equivalent fluence for its validity., 形態: カラー図版あり, 形態: PDF, Physical characteristics: Original contains color illustrations, Physical characteristics: PDF, 資料番号: AA0061912001, レポート番号: SES-2012-001}, publisher = {宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS), Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)}, title = {X線天文衛星すざく太陽電池パドルの軌道上発生電力解析}, year = {2013} }