Abstract: Covering more than 60% of the satellite surface, multi-layer thermal insulation is an important medium in restraining the sources of strong electromagnetic environment in space, as well as a necessary thermal control component. Compared with internal components, the satellite surface is directly impacted and acted upon by energetic particles, resulting in a serious electrostatic threat on orbit. The high energy electrons can easily penetrate the milli-meter thin film of the multi-layer insulation, deposit on the internal dielectric material of the insulation and finally form electric fields. According to the composite structure characteristics of multi-layer thermal insulation components, the reasonably optimized internal charged physical model and calculation model are established to simulate the electronic transport process of GEO environmental electrons in typical multi-layer thermal insulation components, and the electric field distribution characteristics of different layers are calculated. The simulation results show that the charging potential of the multi-layer spacer polyester mesh can be as high as 9.7×10⁸ V/m in the worst GEO electron radiation environment, where a risk of discharge exists. The strengths of the electric fields at the grounding edge and the corner of the polyester mesh are the highest and the amplitude of the electric field distortion is huge. The risk of multi-layer charge and discharge mainly comes from the poor grounding caused by the non-intimate contact between the polyester mesh and the reflective screen. It is recommended to increase the contact effect of the polyester mesh and the reflective screen by shortening the stitching distance of the cotton thread to reduce the risk of multi-layer charge and discharge.

Key words: multi-layer thermal insulation, GEO satellites, charge-discharge effect, internal charging, charge transport model