低轨道太阳电池势垒效应及其对卫星绝对带电影响

Effect of Solar Array Potential Barrier on Floating Potential of Spacecraft in Low Earth Orbit

针对太阳电池正偏置工作电压和玻璃盖片表面负电位产生的势垒及其对低轨道航天器绝对带电的影响。本文首先基于轴对称模型结构分析了电池间隙裸露导体尺寸对太阳电池势垒效应的影响。研究结果表明,太阳电池势垒效应随着电池裸露导体尺寸增大而减弱。并且利用航天器与等离子体相互作用分析软件,通过PIC(Particle In Cell)方法研究了低轨道等离子体环境下太阳电池间隙裸露导体尺寸和工作电压对航天器悬浮电位的影响,并将仿真分析结果与无限大平板电流收集模型计算结果进行了对比分析,对比悬浮电位仿真分析与模型计算结果表明,太阳电池产生的势垒效应阻碍了航天器对电子电流的收集。

The correlation between thepotential barrier,originated from the positive operation voltage of the solar array and the negative potential on the insulating cover-glass,and the floating potential of spacecraft in low earth orbit was empirically simplified,mathematically modeled,theoretically analyzed in current balance theory and numerically simulated with PIC and Spacecraft Plasma Interaction software. The impact of the solar array＇s metal interconnect area exposed to dense cold plasma and the positive operation voltage of solar array,on the potential barrier of solar array and the floating potential of spacecraft was investigated. The calculated results show that the potential barrier increases with an increase of the metal interconnect area. As shown in the simulated results,the potential barrier of solar array has a negative impact on the electron current collection of metal interconnects of solar array and a major impact on the floating potential of spacecraft.