基于矩形窗时域滤波算法的热导检测系统设计与应用

变压器油中溶解气体在线监测的关键是气体检测的传感器技术，如何准确测量、分析油中二氧化碳气体的含量是这一技术的难点。为解决这一难题，设计了一种基于矩形窗时域滤波算法的热导检测系统。该系统采用新型热导传感器TCS208F，针对其输出信号小，采集分析难度大的问题，采用模拟滤波和数字滤波相结合的方法，完成热导检测系统的软硬件优化设计，实现二氧化碳气体微弱信号的采集与分析。该方法有效地抑制了各种类型的噪声干扰，提高了系统测量的精度与灵敏度，实现了微量气体浓度的准确测量，克服了传统气体热导检测的缺点。

Design and application of the thermal conductivity detection system based on the rectangular window time-domain filtering

The key of on-line monitoring of dissolved gas in transformer oil is the sensor technology of gas detection, in which how to accurately measure and analyze the content of carbon dioxide in oil is the technical difficulties. To solve this problem, this paper designs a thermal conductivity detection system based on rectangular window time-domain filtering algorithm. The system uses a new thermal conductivity sensor TCS208F, utilizes the combined method of analog and digital filtering for its small output signal and difficult issues in signal acquisition and analysis. Finally, this paper completes the optimum design of hardware and software of thermal conductivity detector system, realizes the collection and analysis of weak signal of carbon dioxide gas. This method effectively suppresses the noise of various types, improves the accuracy and sensitivity of system measurement, achieves the accurate measurement of trace gas concentrations, and overcomes the shortcomings of traditional gas thermal conductivity detection.