低倾角轨道微小遥感卫星的热设计及验证

Thermal design and verification of micro remote-sensing satellite in low inclination orbit

为了满足卫星平台热控指标及空间相机桁架的精密控温需求,同时尽量降低卫星主动热控功耗,合理规划了卫星热传递网络,并进行了相机高精度控温设计。根据卫星结构布局、单机功耗分布和低倾角空间外热流特点进行了任务分析,确定了热设计的重点和难点。然后进行了卫星热控系统的详细设计,通过标定测温电路,采用多层表面均温措施和开设各组件间的热交换通道,合理利用整星资源进行了一体化热控设计,并进行了热仿真分析。最后开展了卫星热平衡试验,对热设计方案进行验证。卫星在轨飞行数据表明,卫星各单机温度处于-0.5~28.8℃,相机桁架的温度波动和均一性小于±0.15℃,在轨平均功耗为9.3 W,满足平台的控温指标与相机的成像需求。热控分系统质量为1.5 kg,仅占比整星质量的3%,为低成本商业遥感卫星的热设计奠定了良好的基础。

There is a need to satisfy the thermal control requirements of satellite platforms,achieve precise temperature control of space camera trusses,and minimize the power consumption of thermal control systems.In this study,the heat dissipation channel of the electronic equipment was planned reasonably,and the high-precision temperature control of a space camera was designed.First,mission analysis was performed based on the satellite structure layout,the power consumption of the electronic equipment,and the heat flow in low inclination orbit,and thus,the key and difficult points of the thermal design were identified.Next,a detailed design of the satellite thermal control system was carried out.A calibration method for the temperature measurement circuit was proposed,a multilayer-surface temperature equalization approach was adopted,and heat exchange channels between different components were opened.Hence,the entire satellite resources were reasonably used for integrated thermal control design.Finally,satellite thermal balance tests were performed to verify the thermal design.The temperature of the satellite in orbit indicates that the electronic equipment temperature ranges from-0.5 to 28.8℃,and the temperature fluctuation and uniformity of the camera truss are lower than±0.15℃.In addition,the average power consumption of the thermal control system in orbit is 9.3 W,which satisfies the temperature control index conditions of the platform and the focusing requirements of the camera.The weight of the thermal control subsystem is 1.5 kg,which accounted for only 3%of the total satellite weight.This study lays a good foundation for the thermal design of low-cost commercial remote-sensing satellites for future investigations.