【作者】 胡海林；

【导师】 吕玉祥；

【作者基本信息】 太原理工大学 ， 物理电子学， 2008， 硕士

【摘要】 当今气体传感器技术发展日新月异,应用日益广泛,电化学气体传感器作为其中重要的一个分支,也得到了广泛的应用,但在气体浓度精确测量中主要存在两方面的问题:交叉灵敏度问题和气体传感器的特性漂移问题。这些问题长期以来一直困扰着人们,尤其在一些需要进行长期在线监测的场合。本文以导师项目(为某电力公司开发一套完整的环境参数监测系统)中的子项目为课题,开发了一套完善的电化学气体传感器性能参数测试系统,可获得传感器的最佳工作点,为由交叉灵敏度和特性漂移引起测量误差的修正补偿提供依据。根据实际测试需求,设计了测试电化学气体传感器系统的总体方案,由增强型51单片机构成的下位机与基于虚拟仪器技术的上位机共同组成测试系统,利用定电位电解二氧化硫传感器对该系统进行了相应的实验验证。下位机分为硬件部分与软件部分,主要包括下位机芯片的选择、下位机与上位机通讯端口的选择与实现、下位机模拟端口的配置、数据采集的实现以及与上位机通讯软件的设计;上位机主要是利用虚拟仪器技术,实现了仪器界面的设计和各功能模块软件的编写,具体包括串口通信设计、通道参数配置、零点漂移测量、线性相关测量、温度漂移测量、气体选择性测量、响应/恢复时间测量、结果数据存储以及报表生成等功能模块。通过对定电位电解二氧化硫传感器各种特性参数的实际测量得出:传感器的最佳工作温度为20℃左右;零点漂移为总量程的±2.3%;在气体浓度小于72.3ppm时,线性相关系数为0.993;响应时间为15s;恢复时间为19s;气体选择性方面,分别对浓度为100ppm的一氧化碳、硫化氢、一氧化氮进行了测量,传感器的输出电压值依次为0.227V、0.233V、0.208V。从实验结果可以看出,此系统可以很好地测量气体传感器各种特性的完整参数和曲线,为气体传感器的进一步研究和应用提供可靠的依据。更多还原

【Abstract】 Nowadays, gas sensor technology develops quickly and becomes more widely available. As one of the branches, electrochemical gas sensor is also widely applied. But on the aspect of precise measurement of gas concentration, there are two main problems. One is cross-sensitivity, the other is characteristic drift of gas sensor. These problems have puzzled people for a long time, particularly on a long-term on-line gas monitoring. This paper focuses on the sub-item of the supervisor’s research project （develop a comprehensive environmental parameters monitoring system tor a power company）, and develops a comprehensive test system for electrochemical gas sensor performance parameters. Therefore the best point of gas sensor can be available so as to provide a basis for the amendments compensation of measurement error caused by cross-sensitivity and characteristic drift.Taking into account the actual testing requirements, the author presented an overall scheme testing electrochemical gas sensors system, which is mainly made up of the enhanced 51 MCU and PC based on the virtual instrument technique. Moreover, the corresponding experimental verification for the designed system is also given by means of the fixed electric potential electroanalysis sulfur dioxide sensor. Slave computer is divided into the design of hardware and software parts, including the choice of chip for slave computer, the choice and implementation of communications port, the configuration of slave computer analog ports, the realization of data acquisition and the design of communication software. The program of PC realized the design of the instrument interface and the compilation of functional modules software primarily by virtue of virtual instrument technique. These modules include the serial communication design, channel parameters configuration, zero shift measurement, linear correlation measurement, temperature drift measurement , cross-sensitivity measurement, response / recovery time measurement, data storage, and the report program generator.It can be educed from the measurement of various characteristic parameters of the fixed electric potential electroanalysis sulfur dioxide sensor that the best operating temperature of the sensor is about 20℃, the zero shift takes up±2.3% of the full scale. When the gas concentration is less than 72.3 ppm, the linearly dependent coefficient is 0.993; response time is 15 s; and recovery time is 19 s. As for cross-sensitivity, the author separately measured CO, H₂S, and NO with the concentration of 100 ppm, the sensor output values are 0.227 V, 0.233 V, and 0.208V in sequence. From the experimental results, it can be seen that the integrity of the various parameters and curves of the gas sensor can be measured with this system, and it can provide a reliable basis for further study and application.更多还原