大椭圆轨道航天器介质材料深层充电仿真分析

为研究大椭圆轨道(HEO)航天器介质深层充电规律特征,基于FLUMIC模型建立辐射带电子环境模式,初步分析了诱发HEO深层充电的高能电子环境,计算了介质材料在HEO环境下的充电特征,并与地球同步轨道(GEO)下的情况进行对比。结果表明,HEO电子平均积分通量与GEO的相比处于同一量级,但存在明显波动,这将导致卫星在轨运行时,其上介质平均充电电位上升,增加内带电的风险。HEO介质平均充电电位为GEO的1.3倍,瞬时电位以12 h周期波动,电位最大值较环境电子通量最大值有数十min延时。增加屏蔽层厚度和减小介质厚度均能有效减缓HEO卫星介质电位波动,并降低内带电的风险。

Simulation of deep dielectric charging for highly elliptic orbit spacecrafts

To determine the charging characteristics of the HEO satellite, a model is constructed based on the FLUMIC model of the ESA in the manner of electrons in the radiation belt, as in the HEO electron environment evaluation. The main characteristics of the deep dielectric charging on the HEO satellites are studied. The results are compared with those in the GEO. It can be concluded that the daily-averaged electron flux of the HEO and the GEO are in the same level, while the instantaneous flux sees significant fluctuations, which might increase the charged potential and the risk of the internal charging. It is shown that the average charged potential in the HEO is about 1.3 times higher than that in the GEO, while the instantaneous potential has a 12-hour period. The results demonstrate that the peaks of the charged potential have tens of minutes delay in contrast to the peaks of the electron flux. It is recommended that a thicker shield layer and a thinner dielectric layer can mitigate the fluctuations of the charged potential and reduce the risk of the internal charging during HEO missions.