等离子体环境下孤立导体表面充电时域特性研究

Characteristics plasma environment isolated conductor surface charging time domain

航天器在等离子体环境下的表面充放电受到多种因素影响,其中充电时间是影响静电放电频次的一个重要因素.本文从等离子体的微观结构出发,同时考虑材料参数特性,在对每个粒子运用力学原理的基础上,以统计方法推导出孤立导体球表面充电电位时域表达式.利用电位时域表达式推导出孤立导体球净电荷量时域表达式及静电场能量时域表达式.以较低非极地地球轨道和较高地球同步轨道为例对孤立导体球电位、净电荷量及静电场能量的时域特性进行了讨论,分析了空间环境参数和导体球半径大小对表面充电的影响,总结出等离子体环境下孤立导体表面充电时域特性规律.

Spacecraft surface charging and discharging in a plasma environment are affected by many factors, and the charging time is an important factor to influence the discharging frequency. In this paper, considering microstructure and material parameters of the plasma characteristics, appling the principles of mechanics to each particle, and using statistical methods, the expression of isolated conductor ball surface charging potential time-domain is deduced. Using the general expression of voltage, we deduce the expression of the time domain of electrostatic charging quantity of isolated conducting sphere and the expression of the time domain of the electrostatic field energy. Taking low earth orbit and geosynchronous orbit for example, we discuss the potential of isolated conducting sphere, static load and the characteristics of the electrostatic field energy. The influences of space environment parameters and the size of the conducting sphere radius on surface charging are analyzed. The laws of the time domain of isolated conductor surface charging in plasma environment are summarized.