evaluation of end-of-life performance of gaas solar cell in gto mission using ion thruster

Paper number

IAC-17,C2,IP,5,x40830

Author

Dr. Xin Gao, Science and Technology on Vacuum Technology and Physics Laboratory, Lanzhou Institute of Physics, China

Year

2017

Abstract

The geosynchronous transfer orbit (GTO) is usually used as the intermediate orbits between the injection orbit and the Geosynchronous Orbit for communication satellites. GTO is characterized with an intense radiation environment, mainly composed of a combination of electrons and protons. However the transfer time may last as long as six months for ion thruster with a thrust of several tens of mN, compared to that of several days for a large thrust of thruster. Exposure to these charged particles typically degrades the electrical performance of solar array, thus limiting the lifetime of the missions. Therefore, to be used in the intense space radiation environments, understanding the radiation response of solar cell is extremely important for accurate predictions of the expected mission lifetime. 
    The effects of GTO radiation environments on the degradation of GaAs cells are investigated to provide the reference for solar array design. The on-ground irradiation experiments were performed to evaluate radiation effects of electrons and protons on these solar cells, and also to provide experimental data for predictions of the cell performances under the space radiation environments. For this cell type I-V characteristics were obtained as a function of radiation fluence using electrons (1.0, 1.5 and 2.0 MeV) and protons (3, 5, 8 and 10 MeV). The prediction results of the performance degradations of the GaAs cells are presented as a function of cell material and cover glass, using the displacement damage dose methodology for analyzing and modeling. This study provides reference data for the design of the GaAs solar array in the intense space radiation environments to ensure the security and reliability of on-orbit spacecrafts.

Abstract document

IAC-17,C2,IP,5,x40830.brief.pdf

Manuscript document

(absent)