屏蔽厚度对电路板充电防护仿真分析

Simulation of the influence of shielding layer's thickness on charging hazard of circuit board

卫星深层介质充放电是造成卫星异常的主要空间环境效应之一。本文基于地球同步轨道(GEO)为目标防护设计轨道,以NASA4002A上提出的GEO轨道最恶劣电子能谱作为环境输入参数,采用Geant4-RIC方法计算了不同屏蔽层厚度下,双面覆铜接地的厚度为2.0 mm的电路板介质的深层介质充电电场。计算结果表明,随着屏蔽层厚度的增加,介质内最大充电电场呈指数降低,当屏蔽层厚度大于1.4 mm等效Al时,充电电场小于106 V/m,没有深层介质放电风险。

Deep dielectric charging and discharge is one of the most harmful factors for spacecraft. In this paper,by using GEANT4-RIC method,the deep dielectric charging electric field of 2.0 mm thickness circuit board is calculated under the worst-case internal spectrum in Geostationary Earth Orbit(GEO) from NASA4002 A. The simulation result shows that the maximum dielectric charging electric field decreases exponentially with the increasing of the thickness of the shielding layer. When the thickness of the shielding layer is above 1.4 mm Al,the maximum electric field is below 106 V/m,which shows no deep dielectric discharge hazard.