LEO太阳电池一次放电模型研究

空间等离子体作用下,太阳电池一次放电是诱发二次放电的主要原因。目前缺乏适合工程应用的一次放电快速评估模型。文章借鉴辉光放电理论,针对太阳电池三联点结构提出一次放电一维简化模型,用于评估太阳电池设计对放电脉冲强弱的影响。模型计算结果表明,增加玻璃盖片厚度和电池串联间隙有助于提高一次放电起始电压,一次放电频率随着太阳电池偏压和表面二次电子发射系数增加而增大,放电电流随着太阳电池偏压和电池阵电容增加而增强。该模型计算结果与试验测试结果基本一致,且比其他模型计算过程简单,可以为太阳电池设计中一次放电现象快速评估提供参考。

1D modelling of primary arcs on LEO solar array

The primary arcs on the solar arrays are the main cause of secondary arcs, a serious threat to the safety of spacecraft operation. The primary arcs were widely studied but without a fast assessment model. A 1D model of the primary arcs is developed to explain the experimental results under different discharging conditions. Both effects of the electric field enhanced emission and the electron impact ionization are included by using an equivalent capacity model for the boundary condition. The primary arc characteristics under different conditions can be predicted. The effects of the differential surface potential, the cover glass thickness, and the secondary emission coefficient are studied. It is shown that the onset voltage of the primary arc grows with the increase of cover glass thickness and the solar cell gap distance, the discharging frequency is affected by the bias voltage and the secondary emission coefficient, and the peak current is proportional to the bias voltage and the solar array capacitance. The results are consistent with experiments and can provide a fast assessment of the primary arc in a solar array design.