便携式CO／CO2二合一不分光红外分析仪

简要介绍便携式ＣＯ／ＣＯ２二合一不分光红外分析仪的原理，结构，技术指标及其应用。     

基于非分散红外(NDIR)原理的煤矿甲烷检测仪

介绍了一种基于非分散红外(NDIR)原理的煤矿甲烷检测仪的总体设计。该检测仪使用进口红外检测元件,以新型电调制光源代替机械调制光源,实现了对煤矿井下大范围甲烷浓度的实时测量、液晶显示和超限声光报警等功能,并把甲烷浓度值转化为与煤矿其他设备兼容的4~20 mA标准模拟电信号,最后给出该检测仪在甲烷体积分数为0~10%的测量结果。     

非色散红外气体传感器稳态扩散高斯分布浓度校正方法

流程工业中气体浓度测量至关重要。非色散红外传感器是一种基于不同气体对红外光吸收强度差异性测量气体浓度的传感器,气体浓度测量精度高,广泛用于流程工业中CO₂和N₂O气体浓度测量。非色散红外传感器内气体不均匀扩散使气体浓度测量会产生原理性误差,需要得到气体在传感器气室内达到稳态扩散时间降低浓度测量误差,提高测量精度。本文提出一种非色散红外传感器高斯分布扩散模型预测气体稳态扩散时间计算方法,14组不同条件下CO₂和N₂O的仿真实验得到本文提出高斯扩散模型的拟合度分别为0.82和0.80,验证所提出高斯模型预测气体稳态扩散时间的鲁棒性。本文所提方法非色散红外传感器浓度测量不均匀扩散产生误差补偿提供保障。     

基于NDIR原理的红外CO浓度检测仪

该文介绍了一种基于非分散红外(NDIR)原理的红外CO浓度检测仪的总体设计,该检测仪使用新型红外传感器,以新型电调制光源代替机械调制光源,实现了对CO浓度的实时测量、LED显示和超限声光报警等功能,并通过后期的实验测试,验证了该检测仪在测量精度、范围等方面的优势。     

基于非分散红外(NDIR)原理的煤矿CH_4检测仪设计

非分散红外(NDIR)气体检测技术作为一种先进的气体分析技术逐渐发展起来。因其具有响应时间快、检测精度高、寿命长、性能稳定、检测范围宽和不受检测环境内其他气体干扰等特点,而被广泛应用于煤矿安全监控领域当中。对基于非分散红外(NDIR)原理的煤矿CH4检测仪设计进行分析,从非分散红外检测的理论基础、硬件结构、监测仪软件设计、试验和结果方面做出系统的论述。     

Methods of the gas concentration sinusoidal and step changes generation for dynamic properties of gas concentration meters testing

The generation methods of a gas concentration sinusoidal and step changes for dynamic properties assessment of the fast gas concentration meters are described. The need of such fast measurements occurs together with the rising scientists’ interest in contaminants and microorganisms dispersion in the air, especially during the tests of the risk of infection. While the laboratory tests are performed, the tracer gas instead of a infected air is used. Due to the high selectivity, good long-term stability and a wide measurement range, the infrared absorption method for measuring the gas concentration is used. The dynamic properties of this method are limited by the need of the exchange of the gas sample in the measuring chamber. Both constructed generators allow to obtain gas concentration changes with specified amplitude and frequency. The results of step and sinusoidal tests of selected CO₂ concentration meter were compared and they showed a good agreement.     

基于NDIR方法的机动车排放气体传感器

针对机动车尾气成分检测中存在的各种问题,根据不分光红外(NDIR)方法的基本原理设计了新的测量方案。传感器同时测得了CO、CO2、HC化合物3种气体的浓度,并以数字信号方式通过串行口输出测量结果,避免了传输过程中的干扰,可以很方便地应用到具有串口的各种数字处理设备中。用标准气体对传感器进行了实验标定,其结果表明传感器测量精度达到国家标准要求。     

Development of fast-response portable NDIR analyzer using semiconductor devices

In this paper, a novel fast response NDIR analyzer (FRNDIR), which uses an electrically pulsed semiconductor emitter and dual type PbSe detector for the PPM-level detection of carbon dioxide (CO₂) at a wavelength of 4.28 μm, is described. Modulation of conventional NDIR energy typically occurs at 1 to 20 Hz. To achieve real time highspeed measurement, the new analyzer employs a semiconductor light emitter that can be modulated by electrical chopping. Updated measurements are obtained every one millisecond. The detector has two independent lead selenide (PbSe) with IR band pass filters. Both the emitter accuracy and the detector sensitivity are increased by thermoelectric cooling of up to —20 degrees C in all semiconductor devices. Here we report the use of semiconductor devices to achieve improved performance such that these devices have potential application to CO₂ gas measurement and, in particular, the measurement of fast response CO₂ concentration at millisecond level.     

便携式非分光红外吸收型二氧化碳传感器

随着传感器和计算机技术的不断进步和完善,便携式仪器开始发展起来.根据国内目前红外二氧化碳气体传感器技术尚未成熟,研究了一种具有广泛开发的应用前景,并以其测量范围宽、灵敏度高、响应时间快、选择性好、抗干扰能力强、成本低等特点的红外吸收型便携式CO2气体传感器,迎合了气体传感器的发展方向.透过分析仪的红外检测技术原理和系统方案,给出其软硬件的实现.基于单片机AT89C52设计的红外二氧化碳浓度检测兼具报警功能的掌上型便携式传感器,实现了二氧化碳浓度检测的高精度、高稳定性和便携式智能化,也可以作为分布式传感系统和传感器网络化的传感器,用于实时、远程监控.     

基于GWO-BP神经网络补偿的SF6红外气体传感器

为实现电力系统中SF 6气体的有效监测与控制,本文基于非色散红外原理(NDIR),设计了一种SF 6气体传感器。但是,在实际的测量中,环境的温度与气压差异性容易影响SF 6气体浓度检测装置的检测精度,因此需要采取适当的方法消除环境引起的测量误差。本文采用灰狼智能优化算法—误差反向传播(GWO-BP)神经网络对环境温度与气压变化引起的测量误差进行了补偿,并与其他补偿方法作了比较。分析得出:进行补偿后的浓度数据在0~2000 ppm范围内误差为±15 ppm,满量程误差为0.75%FS,有效提升了传感器的测量精度与稳定性。相较于电路补偿法,该方法有更高的测量精度,并且降低了传感器的体积和成本。