基于三线制热敏电阻的温度控制系统  

Temperature Control System Based on Three-wire Thermistor

作　　者：李幸 周凤星[1] 严保康[1] LI Xing;ZHOU Feng-xing;YAN Bao-kang(College of Information Science and Engineering,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学信息科学与工程学院

出　　处：《仪表技术与传感器》2019年第7期61-66,共6页Instrument Technique and Sensor

基　　金：国家自然科学基金项目(61174106);武汉科技大学大学生科技创新基金研究项目(17ZRC166)

摘　　要：为满足某氮氧化物(NO x)传感器精度测试系统“传感器内部温度应维持在750 ℃以确保测试结果的准确性”的要求,通过三线制加热电路加热传感器内部热敏电阻,利用滤波算法对所采集电压信号进行预处理,并借助于电阻-电压多项式拟合法及阻-温特性分段最小二乘法非线性校正得到温度-电压关系式,最后辅以模糊自适应PID控制以达到控温750 ℃的目的。实验证明:该温度控制系统能使传感器内部温度稳定在(750±2)℃,满足了检测系统的需要。To meet the requirement“the internaltemperature of the sensor should be maintained at 750 ℃ to ensure the accuracy of the test results”that a nitrogen oxide (NO x)sensor precision testing system proposed.In this paper,the collected voltage signal is preprocessed by the internal thermistor of the heating sensor of the three-wire heating circuit and the filtering algorithm.By means of resistance-voltage polynomial fitting method and piecewise least square nonlinear correction of resistance-temperature characteristic,the temperature-voltage relation is obtained.Finally,a fuzzy adaptive PID control is used to maintain the temperature at about 750 ℃.The experimental results show that the internal temperature of the sensor can be stabilized at 750 ℃± 2 ℃,which meets the needs of the testing system.

关 键 词：三线制加热 多项式拟合 最小二乘法 非线性校正 模糊自适应 PID 控制 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]