太阳辐照度监测仪主动热控测试系统设计

太阳辐照度监测仪（SIM）作为某卫星的有效载荷，每个轨道周期从背阴区到光照区环境温度变化剧烈，而太阳辐照度监测仪的精密测量需要仪器处于稳定的温度环境下。为保证仪器在轨测量时工作在正常温度下，设计了太阳辐照度监测仪主动热控测试系统。根据热分析的结论，确定仪器测温点和加热区。以单片机和FPGA为硬件平台，完成各测温点温度的采集、处理和分析，从而控制各加热区的加热状态，实现仪器在背阴面时对仪器各加热回路的主动加热控制，并通过上位机进行实时监控。实验结果表明：在主动热控系统的控制下，仪器各测温点在模拟外热流环境下能够维持在目标温度平均误差小于0．1℃水平，该系统设计能够达到维持温度稳定的效果，满足太阳辐照度监测仪主动热控的设计要求。

Design of active thermal control test system for solar irradiance monitor

Solar irradiance monitor （SIM） operates as a satellite payload, on a sun-synchronous orbit, will experience a shady side and a light side each orbital period. From the shady area to light area, changes in the ambient temperature are intense, while the instrument needs to be in a stable temperature for accurate measurement of solar irradiance. When measured in-orbit,in order to ensure that the instruments work in a normal temperature,design an active thermal control test system for SIM. According to conclusion of thermal analysis, determine temperature measurement points and heating zone of instrument. By using MCU and FPGA as hardware platform, acquisition, processing and analysis work of each temperature measurement point are completed, so as to control heating state of each heating zone and achieve active heating control for all the heating circuits when the instrument in the shady area, and host computer is used for real-time monitoring. Experimental results show that the instrument can be maintained at the target temperature average error less than 0.1 ~C, in the environment simulating the external thermal flux, through control by active control test system, and the design of this system can meet requirements of active thermal control of SIM.