薄膜热电偶的动态特性及动态补偿研究

Investigation of the Dynamic Characteristic of the Thin film Thermocouple and Dynamic Compensation

针对用于瞬态高温测量薄膜热电偶的动态特性研究问题，本文提出了通过动态补偿来展宽其工作频带，以此来减小动态误差的方法。采用了一种脉冲激光法对薄膜热电偶进行了动态校准实验；利用基于沃尔什函数的建模方法建立了较好的薄膜热电偶动态模型；比一般的最小二乘法具有更高的拟合程度；通过对模型的极点和工作频带的分析，设计了动态补偿数字滤波器，改善薄膜热电偶的动态特性。

On the study of the dynamic characteristic of the thin film thermocouple used in transient high temperature measurement,a dynamic compensation method which can widen the working frequency band and reduce the dynamic error is reported. A pulse laser is used in the dynamic calibration of the thermocouple. A modeling method based on the Walsh function is used to get the dynamic model and the result is better than that by the common least square method.Through the analysis on the pole of the model and the required response time,a dynamic compensation digital filter is designed to improve the dynamic characteristic of the thin film thermocouple.