一种用于星上半导体制冷器的温度控制方法

A Method of Observing and Controlling Temperature of the Black-body Calibration Device in Infrared Radiation Camera

黑体定标是实现红外相机在轨非均匀性校正的主要手段,黑体温度的控温精度及稳定性决定了红外相机在轨定标的可靠性。小面源黑体多采用半导体制冷器对其进行制冷,以达到低温定标点。文章基于恒流源测温电路、静态温度标定法、PID控制方法提出了一种新的定标黑体高精度测温控温方法。本方法中基于恒流源测温方法的高精度测温电路较传统测温电路相比,采用温差取样的方法,可同时获得更宽的动态范围和更高的测量精度;本方法中为排除测温电路中放大器噪声带来的干扰,进一步提高测温精度,采用输入与输出直接标定的静态温度标定方法,并采用多项式拟合对标定数据进行拟合,使黑体的测温精度达到±0.05℃;本方法中采用分段式PWM控制方法结合PID算法,实现高精度温度控制,实现起来更方便更准确。本方法通过工程实践,并在试验室环境中进行了验证,通过跟踪黑体温度跟踪曲线,测温、控温精度均能达到指标要求。本方法较传统的黑体测温控温方法具有精度更高、更小型化,适应性更广、可移植性更强等优点,因此可以在红外相机中推广。

The black-body calibration is the major in orbit measure method of Infrared Radiation camera. The temperature controlling precision and stability of the device affect directly to the data validity of calibration. The refrigeration of blackbody facet is always realized by the semiconductor refrigeration. This paper introduces a design of a high accuracy temperature measuring and controlling method of the black-body based on constant current source temperature measuring circuit,static temperature calibration method and PID controlling method. Compared with the traditional temperature measurement circuit,the method of temperature difference sampling in this method can obtain a wider dynamic range and a higher measuring accuracy. In order to exclude the interference noise of amplifier in the temperature measurement circuit and improve the accuracy of temperature measurement,the method of input and output direct calibration of static temperature calibration,and polynomial fitting of the calibration data were used. The blackbody temperature measurement precision can reach± 0. 05℃. The piecewise PWM control method is combined with the PID algorithm to achieve high precision temperature control. The method is verified in the laboratory experiment. The temperature measurement and temperature control precision can reach the requirement of the index by tracking the temperature of the black body.This method has the advantages of higher precision,smaller size,wider applicability,and stronger transferability,so it can be widely used in infrared camera.