应用于IGSO卫星的数字太阳敏感器热控设计

Thermal Control Design of Digital Sun Sensor on IGSO

相对于传统太阳敏感器(热耗为零)而言,国内新研制的数字太阳敏感器线路板上的芯片具有一定热耗。为解决其散热问题,以应用于倾斜地球同步轨道(IGSO)卫星的数字一体化太阳敏感器为例,提出了较为简单有效的热控方案,建立热物理模型对数字太阳敏感器进行组件级热分析,并通过在轨飞行数据验证了设计的合理性。结果表明:对于具有一定热流密度的小尺寸部件而言,在辐射换热面积增幅较为有限的条件下,有效增大其传导换热的热控方案要明显优于加强辐射换热的方案;同时要结合外热流情况,优化选择散热面。此方案可较好地满足印制电路板(PCB)上各芯片结温的一级降额温度指标要求,也可为同类产品的设计提供参考。

Comparing with traditional sun sensor which heat load is zero, a new sun sensor has certain heat load in chips on PCB. In order to solve the problem of heat dissipation, of the digital integrative sun sensor used in the IGSO orbit, a simple effective thermal control design is pro-posed in this paper. The thermal physics model of sun sensor is investigated with assembly level thermal analysis method by applying the I-DEAS software and the rationality of the design can al-so be proved by orbit data. The research results show that for the small dimension structures with some heat flux, on condition of limited increase radiation surface, the thermal control meth-od of enhancing heat conduction is much better than that of enhancing heat radiation. At the same time, considering the external heat flux, the selection of heat dissipation surface is optimized. The selected thermal control design meets not only the target temperature requirement of the shell outside surface, but also the primary derating requirement of chips junction temperature on PCB. In addition, it can provide scientific references for the design of other similar products.