空间遥感器CCD模块热设计与仿真分析

Thermal Design and Simulation of CCD Module in Space Borne Remote Sensor

某星载差分吸收光谱仪是一种高精度的空间光学遥感器,利用成像光谱仪成像到电荷耦合器件(charge coupled device,CCD)面阵探测器,获取高光谱、高空间分辨率的光谱信息。由于采用了多块CCD作为关键的探测器,CCD模块的温度水平、波动范围和速率、每轨温度波动及温度梯度对仪器的正常工作与测量精度有较大影响,温控指标要求较高。由于光机结构紧凑复杂,且需兼顾光路系统的温度要求,导致CCD模块的散热成为整个系统中的难点。综合分析了该太阳同步轨道载荷的外热流变化情况,针对CCD模块的结构布局特点及热耗分布情况,为满足探测器对温度环境的要求,提出了被动热控为主,主动热控为辅的设计方案;利用I-DEAS/TMG热分析软件对光谱仪CCD模块的在轨温度水平进行了仿真计算,得到典型工况下各CCD散热环节的温度分布及温度波动情况;计算结果显示:紫外光通道CCD发热面温度在22℃以下,可见光通道CCD发热面温度在15℃以下,每轨温度波动在2℃以内。光学箱侧板温度较均匀,设计的导热路径合理有效,能够将CCD模块热耗及时排散,同时将CCD发热面温度控制在较好的范围内。结果满足指标要求,热设计合理可行。

A space-borne differential absorption spectrometer is a high precision aerospace optical remote sensor. It obtains hyperspectral, high spatial resolution spectral information by using CCD （charge coupled device） detectors. Since they are key detectors, the performance of the entire instrument is largely determined by CCDs. The temperature of CCD modules has It leads to severe temperature target. Due to the a greater impact on the instrument measurement accuracy complex and compact structure, it gets harder to cool and control the CCD modules＇ temperature. To meet the detector temperature requirement, a thermal control scheme is presented by comprehensively analyzing the structure and power distribution feature of CCD modules as well as the space heat flux at sun-synchronous orbit. Thermal analysis tool I-DEAS/TMG is utilized to compute temperature distribution and fluctuations in several typical operating conditions. The results show that the temperature of CCD in ultraviolet channel is below 22 ℃, in visible channel is below 15 ℃ ; the fluctuation of temperature in different circle is under 2 ℃. The design of heat conduction path is verified to be rational and efficient to transfer heat from CCDs. The temperature of CCD heating surface is under control and within the preferred range