GEO卫星多层隔热组件充放电特性仿真

多层隔热组件包覆于卫星外表面，占据了整星表面的60%以上，既是必要的热控组件，也是抑制空间强电磁环境源的重要载体。相较于卫星内部组件，星表直接面临高能粒子的冲击与作用，导致其在轨面临的静电威胁极为严峻。其本质原因是高能电子穿透多层隔热组件的面膜，沉积于多层组件内部间隔层，进而在介质材料层形成了内建电场，造成静电放电效应。针对多层隔热组件的复合结构特点，建立了合理优化的内带电物理模型及其计算模型，模拟了GEO环境电子在典型多层隔热组件电子输运过程，进而计算明晰了间隔层涤纶网的电场分布特性。结果表明，在GEO恶劣电子辐射环境下，多层涤纶网充电电场强度可高达9.7×10⁸ V/m，存在放电风险；涤纶网接地边、角处的电场强度最高且电场畸变幅度巨大；多层充放电风险主要来自涤纶网与反射屏之间的非紧密接触而伴随的不良接地情况，建议通过加密棉线缝合间距以提升涤纶网与反射屏的接触效果，从而降低多层的充放电风险。

Simulation of internal charging characteristics for multi-layer thermal insulation in GEO satellites

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.