中文摘要：

地球同步轨道航天器在地磁亚暴环境下处于向光面和背光面的两侧会产生电位差。本文利用高能电子和高能离子的双麦克斯韦分布拟合同步轨道环境等离子体并加入二次电子和光电子的影响,建立了航天器的三维计算模型,利用基于PIC（Particle In Cell）方法的仿真程序,计算了航天器表面各材料的充电电位及其附近的等离子体的电位分布,以及低能电子、高能电子、二次电子和光电子的密度分布和充电电流分布,最后探讨了航天器不同表面材料电势随时间的变化情况。

英文摘要：

The surface charging of geosynchronous orbit （GEO）spacecraft, originated from the large potential difference between sunlit and shadowed areas in geomagnetic sub-storms, was approximated, modeled, and simulated with particle-in-cell （PIC） software. The distributions of the high and low energy electrons and ions in the superposed plasma were fitted with double Maxwellian plasma model;the impact of the secondary electron and photoelectron on surface charging was evaluated. The charging potentials on the surfaces of different materials and the potential distributions of plasma around spacecraft were calculated, and the calculations also included the distributions of charging-current and density of cold and hot electrons, secondary electrons and photoelectrons. In addition, time evolutions of the surface potentials of the materials, such as glass, indium-tin-oxides, and Kapton-tape, were estimated. The simulated results were found to be con- sistent with those reported in the literature.