CN104950018A - Mixed gas detecting system - Google Patents

Mixed gas detecting system Download PDF

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CN104950018A
CN104950018A CN 201510411653 CN201510411653A CN104950018A CN 104950018 A CN104950018 A CN 104950018A CN 201510411653 CN201510411653 CN 201510411653 CN 201510411653 A CN201510411653 A CN 201510411653A CN 104950018 A CN104950018 A CN 104950018A
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gas
detecting
mixed
system
measuring
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CN 201510411653
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Chinese (zh)
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宋海声
吕耕耕
刘岸果
桑晓丹
张梦秋
金威
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西北师范大学
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Abstract

The invention discloses a mixed gas detecting system. The mixed gas detecting system comprises a computer, a NI Labwindows/CVI, a data collecting card, a sensor array, a measuring chamber, a transmitter, a signal conditioner, an A/D converter and a flow controller. The sensor array is installed in the measuring chamber. One end of the sensor array is connected with a terminal board through the signal conditioner and the transmitter. The terminal board is connected with the data collecting card through a cable. The transmitter is connected with the computer through a PCI bus inserting groove. The other end of the measuring chamber is connected with the signal conditioner, the A/D converter and the flow controller. The computer comprises a measuring controlling module, a data collecting module and a data processing and analyzing module. The mixed gas detecting system not only can be used for experiment teaching and studying but also can be used for detecting the content of combustible gas in a mine. The mixed gas detecting system can achieve testing of long-term stability of gas sensors and can serve as a tool for screening the sensors in batch. Thus, efficient and intelligent detecting is achieved.

Description

-种混合气体检测系统 - kind of mixed gas detection system

技术领域 FIELD

[0001] 本发明设及气体检测领域,具体设及一种混合气体检测系统。 Field of gas detection and the invention is provided, particularly a mixture of gases and provided detection system [0001] present.

背景技术 Background technique

[0002] 气体传感器的种类很多,常用的如固态电解质气敏传感器、半导体气敏传感器、声表面波气敏传感器等。 [0002] Many types of gas sensors, such as conventional solid electrolyte gas sensors, semiconductor gas sensors, surface acoustic wave gas sensor and the like. 各类气敏传感器性能差异较大,各自的主要检测对象也不一样,构成的测试系统也不同,然而,几乎所有的都不能用于多种气体检测。 Various types of gas sensors are quite different, the respective main detection target are not the same, the test system configuration is different, however, can not be used for almost all of the plurality of gas detection. 用传感器阵列检测多种气体,气体与传感器的活性材料反应,传感器把化学输入转换为电信号;计算机通过电路部分采集到该些电信号,然后采用模式识别对该些电信号进行处理,来分析和识别所测的气体它是一种基于测量和分析化学传感器中信号的微小变化的新方法W。 Detecting multiple gases, a gas sensor and a sensor array with the active material of the reaction, the chemical sensor is input into an electrical signal; Computer collected by the plurality of electrical circuit section, and the pattern recognition processing these electrical signals to analyze and identifying the test it is a new method for gas measurement and analysis of small changes in the chemical sensor based on a signal W. 采用传感器阵列检测多种气体最主要的应用之一是开发一种便携的、通用的电子鼻,电子鼻具有低能量消耗和较低的维护费用。 Gas sensor array detection using one of the most important applications is the development of a variety of portable, versatile electronic nose, the electronic nose having a low energy consumption and low maintenance costs.

发明内容 SUMMARY

[0003] 为解决上述问题,本发明提供了一种混合气体检测系统,不仅可用于实验教学和研究,也可用来检测矿井中可燃气体含量;能够实现气体传感器的长期稳定性的测试,而且还W作为传感器批量筛选的工具。 [0003] In order to solve the above problems, the present invention provides a hybrid gas detection system, not only for experimental research and teaching, may also be used to detect the combustible gas content mine; to achieve long-term stability of the test gas sensor, but also W sensor as a tool for batch screening. 从而实现了高效智能化检测。 Thereby achieving intelligent and efficient detection.

[0004] 为实现上述目的,本发明采取的技术方案为: [0004] To achieve the above object, the present invention takes technical solutions:

[0005] 一种混合气体检测系统,包括计算机、NIL油windows/CVI,数据采集卡、传感器阵列、测量室、变送器、信号调理器、A/D转换器和流量控制器,所述传感器阵列安装在所述测量室内,所述传感器阵列一端通过信号调理器和变送器连接有接线端子板,接线端子板通过电缆与数据采集卡相连,所述变送器通过PCI总线插槽与所述计算机相连,所述测量室另一端连接有信号调理器、A/D转换器和流量控制器,所述计算机包括测量控制模块, 数据采集模块和数据处理分析模块,测量控制模块提供了可视化的实验控制平台,利用各种菜单和按钮实现整个气体检测系统的功能,包括配制各种不同的气体样本,采集经信号调理电路调理后的各个传感器的输出响应并转换为相应的数字信号存储于文件中,利用Ubview应用软件进行数据处理和分析,最后得出结论并将结果显 [0005] A mixed gas detection system comprising a computer, NIL oil windows / CVI, data acquisition card, a sensor array, the measuring chamber, transmitter, signal conditioning, A / D converter and a flow controller, the sensor array is mounted in the measuring chamber, the sensor array has one end connected to the terminal board, the terminal board via the signal conditioner and a transmitter connected by a cable to the data acquisition card, a PCI bus slots by the transmitter and the said computer connected to said measuring chamber and the other end is connected to signal conditioning, a / D converter and a flow controller, said computer comprising a measurement control module, data acquisition module and the data analysis module, the control module provides a visual measurement of experimental control platform, using a variety of menus or buttons function of the whole gas detection system, comprising formulating a variety of sample gases, the output of each sensor is collected after signal conditioning circuit conditioning the response and converted into a corresponding digital signal is stored in the file utilizing Ubview application software for data processing and analysis, and the final draw significant conclusions results 示在屏幕上。 Shown on the screen.

[0006] 优选的,所述测量室由不诱钢的密闭的容器构成。 [0006] Preferably, the measurement chamber is composed of a sealed container does not induce steel.

[0007] 优选的,所述流量控制器采用JY-LUGB气体流量计。 [0007] Preferably, the flow controller using the JY-LUGB gas flow meter.

[000引优选的,所述数据采集卡采用PCI-1710HG数据采集卡。 [000 cited Preferably, the data acquisition card using PCI-1710HG data acquisition card.

[0009] 本发明具有W下有益效果: [0009] The present invention has the beneficial effects W:

[0010] 不仅可用于实验教学和研究,也可用来检测矿井中可燃气体含量;能够实现气体传感器的长期稳定性的测试,而且还W作为传感器批量筛选的工具。 [0010] Not only it can be used for teaching and research experiments, also be used to detect the combustible gas content mine; to achieve long-term stability of the test gas sensor, but also as a tool W sensor batch screening. 从而实现了高效智能化检测。 Thereby achieving intelligent and efficient detection.

附图说明 BRIEF DESCRIPTION

[0011] 图1为本发明实施例一种混合气体检测系统的原理图。 [0011] FIG. 1 embodiment of a mixed gas detection system schematic embodiment of the present invention.

[0012] 图2为本发明实施例中单个传感器的测量电路。 [0012] FIG 2 measuring circuit in a single sensor embodiment of the invention.

[0013] 图3为本发明实施例的检测系统软件流程图。 [0013] FIG. 3 is a flowchart of a software testing system embodiment of the present invention.

[0014] 图4为本发明实施例中MQ-4传感器电阻随电压变化曲线。 [0014] FIG. 4 embodiment MQ-4 sensor resistance varies with the voltage curve of embodiments of the present invention.

[001引图5为本发明实施例中MQ-3传感器电阻随电压变化曲线。 [001 in FIG. 5 of the present embodiment cited MQ-3 sensor resistance varies with the voltage curve of the invention.

[0016] 图6为本发明实施例中MQ-7传感器电阻随电压变化曲线。 [0016] FIG. 6 embodiment MQ-7 sensor resistance varies with the voltage curve of embodiments of the present invention.

[0017] 图7为本发明实施例中一个具体实施例的测试电路漂移图。 [0017] FIG. 7 embodiment a particular embodiment of the test circuit drift FIG embodiment of the present invention.

[0018] 图8为本发明实施例中另一个具体实施例的测试电路漂移图。 [0018] In another particular embodiment of FIG. 8 test circuit of the embodiment of FIG drift embodiment of the present invention.

[0019] 图9为本发明实施例中另一个具体实施例的测试电路漂移图。 [0019] In another particular embodiment of FIG. 9 embodiment drift test circuit embodiment of the present invention FIG.

具体实施方式 detailed description

[0020] 为了使本发明的目的及优点更加清楚明白,W下结合实施例对本发明进行进一步详细说明。 [0020] In order to make objects and advantages of the invention more comprehensible, the embodiments of the present invention, W is further described in detail. 应当理解,此处所描述的具体实施例仅仅用W解释本发明,并不用于限定本发明。 It should be understood that the specific embodiments described herein are only used to explain the present invention W, not intended to limit the present invention.

[0021] 如图1所示,本发明实施例提供了一种混合气体检测系统,包括计算机、 NIL油windows/CVI,数据采集卡、传感器阵列、测量室、变送器、信号调理器、A/D转换器和流量控制器,所述传感器阵列安装在所述测量室内,所述传感器阵列一端通过信号调理器和变送器连接有接线端子板,接线端子板通过电缆与数据采集卡相连,所述变送器通过PCI 总线插槽与所述计算机相连,所述测量室另一端连接有信号调理器、A/D转换器和流量控制器,所述计算机包括测量控制模块,数据采集模块和数据处理分析模块,测量控制模块提供了可视化的实验控制平台,利用各种菜单和按钮实现整个气体检测系统的功能,包括配制各种不同的气体样本,采集经信号调理电路调理后的各个传感器的输出响应并转换为相应的数字信号存储于文件中,利用Labview应用软件进行数据处理 [0021] 1, the embodiment of the present invention provides a mixed gas detection system comprising a computer, NIL oil windows / CVI, data acquisition card, a sensor array, the measuring chamber, transmitter, signal conditioner, A a / D converter and a flow controller, the sensor array is mounted in the measuring chamber, the sensor array has one end connected through a terminal board signal conditioning and transmitter, connected via a cable terminal board and the data acquisition card, the transmitter via a PCI bus slot and connected to the computer, the other end of said measuring chamber is connected to signal conditioning, A / D converter and a flow controller, said computer comprising a measurement control module, and a data acquisition module data processing and analysis module, the control module provides a visual measurement of experimental control platform, using a variety of menus or buttons gas detection function of the whole system, including the preparation of a variety of different gas samples collected each sensor after signal conditioning circuit conditioning output response and converted to a corresponding digital signal is stored in a file, the application using Labview software for data processing 和分析,最后得出结论并将结果显示在屏幕上。 And analyze, and finally concluded and the results are displayed on the screen.

[0022] 如图3所示,所述测量室由不诱钢的密闭的容器构成。 [0022] As shown in FIG. 3, the measurement chamber is composed of a sealed container does not induce steel. 所述流量控制器采用JY-LUGB气体流量计。 The flow controller using JY-LUGB gas flow meter. 所述数据采集卡采用PCI-1710HG数据采集卡。 The data acquisition card using PCI-1710HG data acquisition card.

[002引如图3所示,Rs。 [002 primer 3, Rs. . ,。 . 为气体传感器的电阻,R1为一定值反馈电阻,R2表示立端可调电阻的有效电阻,Rs、Cl构成低通滤波器,给气敏传感器两端施加的是由稳压二极管提供的参考电压Vuf。 Is the resistance of the gas sensor, a constant value of the feedback resistor Rl group, R2 represents the effective resistance of the standing ends adjustable resistor, Rs, Cl constitute a low pass filter, is applied to both ends of the gas sensitive sensor is a reference voltage provided by zener diode Vuf. 模拟输出信号引入数据采集卡。 The analog output signal into a data acquisition card. 图中Ri、R2W及运算放大器构成反向放大电路。 FIG Ri, R2W and operational amplifier inverting amplifier circuit. 根据"虚断、虚短"原理可得: The "virtual off, virtual short" principle can be obtained:

Figure CN104950018AD00041

[0026] 用S表不气体传感器响应信号。 [0026] The response signal S table is not the gas sensor.

[0027] [0027]

Figure CN104950018AD00042

[002引贝1JS值与气体传感电阻值RssmJ或正比。 [002 primer shell 1JS value and the resistance value of the gas sensor RssmJ or proportional. 因Ri,R2给定,测得V。 By Ri, R2 given, measured V. . ,就可得到气体传感器对被测气体产生的响应值。 , The gas sensor can be obtained in response to the measured value generated gas.

[0029] 电源电压的选择会改变传感器的两端电压,会对传感器的性能造成影响,图4-6 中可W看出传感器两端上的电压在1. 5~8. 5V之间,传感器电阻变化较小(1 %~3% )。 [0029] The selected power supply voltage will change the voltage across the sensor, the sensor will affect the performance, W can be seen in FIGS. 4-6 the voltage across the sensor between 1. 5 ~ 8. 5V, the sensor the resistance change is small (1% to 3%). 我们进行测试时,选择Vuf为10V。 When we test, select Vuf to 10V.

[0030] 在对系统的测试过程中,为尽量擬除传感器对采集电路的影响,我们采用不同阻值的精密电阻替代传感器接入测试电路测试,计算电路的精度和稳定度,表1为测试数据。 [0030] In the process of testing the system, except for the possible impact sensor proposed acquisition circuit, we used an alternative precision resistor of different resistance test access circuit test sensor, accuracy and stability of the circuit is calculated, Table 1 Test data. [003U从表1可W看出,匹配电阻选用100K系统的精确度和稳定度较高,图5为匹配电阻100KQ,经过一天测试电路的漂移图。 [003U W can be seen from Table 1, higher accuracy and stability of 100K matching resistor selection system, FIG 5 is a matching resistor 100KQ, drift through the day of testing the circuit of FIG.

[0032] 表1匹配电阻测试结果 [0032] Table 1 Test results matching resistor

[0033] [0033]

Figure CN104950018AD00051

[0034] 从图7-9中可W看出,电路的漂移为几十至几百欧,小于测试电阻阻值的1%。 [0034] can be seen in FIG 7-9 W, drift circuit is tens to hundreds of Europe, less than 1% of the test resistor. 因此对于此检测系统,在长期的测试情况下,电路是非常稳定的。 So for this detection system in the long term test, the circuit is very stable.

[0035] 本具体实施信号采样采用"电桥法",其测试的原理为;利用电学中"惠斯特电桥" 的方法,电桥的一个臂是两个标准电阻的串联,电桥另一个臂是一个标准电阻和传感器电阻的串联。 [0035] The particular embodiment of the present signal sample a "bridge method", the principle of the test; the arm by an electric "whist bridge" approach, the bridge is the series resistance of the two standards, the other bridge a series arm is a standard resistor and the sensor resistance. 由于传感器电阻的变化会导致电桥的不平衡,测出该种不平衡电压差就可W获得传感器电阻的变化。 Due to changes in sensor resistance will lead to an imbalance of the bridge, an imbalance measure the voltage difference W can obtain the change of the sensor resistance. 由于传感器在测试腔内,测试传感器的电压不是很方便,我们就转而测试匹配电阻的电压。 Since the sensor in the test chamber, the test sensor voltage is not very convenient, we turn to match the voltage resistance test. 通过换算我们可W得到传感器的电阻信号。 We obtained by converting W sensor resistance signal. 在该个系统中,匹配电阻的选择很重要,一般来说,当金属型氧化物传感器未与待测气体接触,其活性材料未吸附气体分子时,电阻值约为2MQ~20MQ;当传感器接触到气体并发生吸附时,其电阻值将会下降。 In the systems, the selection of the matching resistance is important, in general, when a metal oxide-type gas sensor is not in contact with a test, which when the active material non-adsorbed gas molecules, the resistance value of approximately 2MQ ~ 20MQ; when the sensor contacts and the gas adsorption occurs, the resistance value will decrease. 下降后的阻值一般为200KQ~2MQ。 Resistance generally decreases after 200KQ ~ 2MQ. 匹配电阻的阻值应该与传感器的阻值相适应, W保证测试电路输出的响应信号保持在可测试范围的中间部分,从而便于用户的观察W。 The resistance of the resistor should be adapted to match the sensor resistance, in response to the output signal W to ensure that the test circuit may be maintained at an intermediate portion of the test range, thereby facilitating the user to observe W. 还要能够使用户方便的更换匹配电阻,该样才能保证传感器电阻与匹配电阻阻值配合恰当如果传感器电阻变化非常小,还需要加上放大器对电流进行放大再测量,通过采集电路采集的电压信号需要通过数据采集卡进行采集,选用NI公司的1710采集卡,并将电压信号转换为计算机可W识别的数字信号。 Also enables the user to easily replace the matching resistor, to ensure that the sample sensor resistor matching resistor if appropriate with the sensor resistance change is very small, also need to add the current amplifier to amplify re-measurement, the voltage signal acquired by the acquisition circuit required by the data acquisition card, selected NI's 1710 acquisition card and a computer-voltage signal into a digital signal W identified. 为减少电源的波动加入滤波器电路。 Was added to reduce the fluctuation of the power supply filter circuit.

[0036]W上所述仅是本发明的优选实施方式,应当指出,对于本技术领域的普通技术人员来说,在不脱离本发明原理的前提下,还可W作出若干改进和润饰,该些改进和润饰也应视为本发明的保护范围。 [0036] W a only preferred embodiment of the present invention, it should be noted that those of ordinary skill in the art, in the present invention without departing from the principles of the premise, may make various improvements and modifications W, the these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (4)

  1. 1. 一种混合气体检测系统,其特征在于,包括计算机、NILabwindows/CVI,数据采集卡、 传感器阵列、测量室、变送器、信号调理器、A/D转换器和流量控制器,所述传感器阵列安装在所述测量室内,所述传感器阵列一端通过信号调理器和变送器连接有接线端子板,接线端子板通过电缆与数据采集卡相连,所述变送器通过PCI总线插槽与所述计算机相连,所述测量室另一端连接有信号调理器、A/D转换器和流量控制器,所述计算机包括测量控制模块,数据采集模块和数据处理分析模块,测量控制模块提供了可视化的实验控制平台,利用各种菜单和按钮实现整个气体检测系统的功能,包括配制各种不同的气体样本,采集经信号调理电路调理后的各个传感器的输出响应并转换为相应的数字信号存储于文件中,利用Labview应用软件进行数据处理和分析,最后得出结论 A mixed gas detection system, characterized by comprising a computer, NILabwindows / CVI, data acquisition card, a sensor array, the measuring chamber, transmitter, signal conditioning, A / D converter and a flow controller, said the sensor array is mounted in the measuring chamber, the sensor array has one end connected through a terminal board signal conditioning and transmitter, connected via a cable terminal board and the data acquisition card, said transducer via a PCI bus slot and the computer is connected to other end of the measuring chamber is connected to signal conditioning, a / D converter and a flow controller, said computer comprising a measurement control module, data acquisition module and the data analysis module, a measurement control module provides a visual experimental control platform, using a variety of menus and buttons to achieve the overall function of the gas detection system, comprising formulating a variety of sample gases, the output of each sensor is collected after signal conditioning circuit conditioning the response and converted into corresponding digital signals stored in the file, use Labview application software for data processing and analysis, and finally concluded 将结果显示在屏幕上。 The results are displayed on the screen.
  2. 2. 根据权利要求1所述的一种混合气体检测系统,其特征在于,所述测量室由不锈钢的密闭的容器构成。 A mixed gas detection system according to claim 1, characterized in that the measuring chamber consists of a stainless steel sealed container.
  3. 3. 根据权利要求1所述的一种混合气体检测系统,其特征在于,所述流量控制器采用JY-LUGB气体流量计。 A mixed gas detection system according to claim 1, wherein said flow controller using JY-LUGB gas flow meter.
  4. 4. 根据权利要求1所述的一种混合气体检测系统,其特征在于,所述数据采集卡采用PCI-1710HG数据采集卡。 A hybrid according to claim gas detection system according to claim 1, wherein said data acquisition card using PCI-1710HG data acquisition card.
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