CN110243877A - A kind of fast gas quantitative testing device suitable for multiple gases - Google Patents
A kind of fast gas quantitative testing device suitable for multiple gases Download PDFInfo
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- CN110243877A CN110243877A CN201910540776.5A CN201910540776A CN110243877A CN 110243877 A CN110243877 A CN 110243877A CN 201910540776 A CN201910540776 A CN 201910540776A CN 110243877 A CN110243877 A CN 110243877A
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- 239000007789 gas Substances 0.000 title claims abstract description 110
- 238000012360 testing method Methods 0.000 title claims abstract description 21
- 239000000463 material Substances 0.000 claims abstract description 61
- 239000004065 semiconductor Substances 0.000 claims abstract description 58
- 238000004891 communication Methods 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims description 15
- 238000005070 sampling Methods 0.000 claims description 13
- 238000005259 measurement Methods 0.000 claims description 9
- 230000004044 response Effects 0.000 claims description 5
- XOLBLPGZBRYERU-UHFFFAOYSA-N SnO2 Inorganic materials O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 4
- 239000004020 conductor Substances 0.000 claims description 3
- 230000005611 electricity Effects 0.000 claims description 3
- 230000003321 amplification Effects 0.000 claims description 2
- 238000007689 inspection Methods 0.000 claims description 2
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims 4
- 230000035945 sensitivity Effects 0.000 claims 2
- 238000005516 engineering process Methods 0.000 abstract description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 6
- 238000001514 detection method Methods 0.000 description 6
- 238000012545 processing Methods 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
- G01N27/127—Composition of the body, e.g. the composition of its sensitive layer comprising nanoparticles
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- Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Pathology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Immunology (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Nanotechnology (AREA)
- Engineering & Computer Science (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
The invention belongs to gas sensing the field of test technology, more particularly to a kind of fast gas quantitative testing device suitable for multiple gases, including following part: semi-conductor gas sensitive material sensor (1), excitation-sample circuit (2), single-chip microcontroller (3), communication/power interface (4), display screen (5) and power module (6).The present invention can detect resistance and its variation of a variety of semiconductor gas sensor elements, output gas concentration information after calculating accurately, in real time.The device can be used in conjunction with a variety of semiconductor gas sensors, select sensor model number according to different target gas, thus the gaseous species that can detecte are extensive, concentration range is big, applied widely, there is very big application value.
Description
Technical field
The invention belongs to gas sensing the field of test technology, and in particular to a kind of fast gas suitable for multiple gases is quantitative
Detection device.
Background technique
Semiconductor gas sensor is a kind of low cost, highly sensitive gas-detecting device, can be widely applied to industry
The multiple fields such as production process monitoring, the Newly diagnosed of disease, atmosphere pollution detection, have highly important application value.Half
The resistance variations that the response of conductor gas sensor is generated based on semiconductor sensitive material when touching object gas, by resistance
Value output test result after signal processing.Presently commercially available semiconductor gas sensor is mostly type of alarm, i.e., is only determined
Property detection, sensor final output signal be 0 or 1, cannot accurately detect the concentration values of object gas.This kind of sensor is difficult
Meets the needs of high-precision quantitative detection occasion.And at present existing non-semiconductor quantitative gas detector rely on mostly optics,
The technologies such as electrochemistry, it is also different to the processing module of its output signal when detecting a variety of different gases, when not only testing
Between it is long, process is cumbersome, big quantity space and resource are also occupied, so that sensor manufacturing cost greatly increases.Therefore, one kind is designed
Fast gas quantitative testing device based on cheap semiconductor gas sensor will have great practical significance and application value.
Summary of the invention
What it is an object of that present invention to provide a set of based on semiconductor gas sensor be suitable for plurality of target gas it is quick,
Quantitative gas concentration detection apparatus.
The device includes following part: semi-conductor gas sensitive material sensor 1, excitation-sample circuit 2, single-chip microcontroller 3,
Communication/power interface 4, display screen 5 and power module 6, the semi-conductor gas sensitive material sensor 1 include semi-conductor gas
Sensitive material 101, semi-conductor gas sensitive material support base 102 and general semiconductor gas sensitive material sensor interface
103, the semi-conductor gas sensitive material 101 is placed or is coated in semi-conductor gas sensitive material support base 102, is partly led
Body gas sensitive material support base 102 is connected on general semiconductor gas sensitive material sensor interface 103, for spy
Determine gas and generates electric response；Excitation-the sample circuit 2 includes 5V voltage drive module 201, low current signal amplification-
Sampling module 202, electric current heating module 203, the 5V voltage drive module 201 are used to sense for semi-conductor gas sensitive material
Device 1 provides 5V driving voltage, and the electric current heating module 203 is used to provide power for semi-conductor gas sensitive material sensor 1
Continuous controllable heated current, the temperature of controllable semi-conductor gas sensitive material 101 is in room temperature to continuously may be used within the scope of 500 DEG C
It adjusts, the low current signal amplification-sampling module 202 passes through semi-conductor gas sensitive material sensor 1 for real-time measurement
Electric current, signal amplification factor is controllable, thus the sensor resistance variation of 100 Ω to 25G Ω ranges of measurement, detection error <
1%, output delay < 0.2s.
In the present invention, semi-conductor gas sensitive material sensor 1 is heater-type or directly-heated semiconductor gas sensor member
Part.The target response gas of different semiconductor sensitive materials, operating temperature, response concentration ranges are different, therefore can be with
According to practical application request, different semi-conductor gas sensitive materials is selected to be placed in semi-conductor gas sensitive material sensor 1,
Including but not limited to SnO2Material, block SnO2Material, nano ZnO material, nanometer WO3Material, powder WO3Material etc..According to inspection
Survey demand, the present apparatus design the required sensor element that can purposefully arrange in pairs or groups, and have broad applicability.
The single-chip microcontroller 3 is STM8S series monolithic, with the following functions:
(1) low current signal amplification-sampling module acquisition voltage signal is read by I2C bus；
(2) basis presets value and generates pwm signal control electric current heating module output power；
(3) according to presetting and sensor actual resistance, by numeral output control low current signal amplify-sample mould
The magnifying power of block；Based on multinomial algorithm, it is electric in real time that semi-conductor gas sensitive material sensor is calculated by the voltage signal read
Resistance value calculates gas concentration value to be detected further according to pre-set semi-conductor gas sensitive material working sensor curve；Storage
Deposit the setting of low current signal amplification-sampling module magnifying power, the heating power setting of electric current heating module and semi-conductor gas
The configuration informations such as sensitive material working sensor curve；
(4) UART bus can be forwarded to through CH340 chip by communication/power interface read or rewrite single-chip microcontroller with confidence
Breath, and read low current signal amplification-sampling module output voltage signal value and gas concentration Value Data to be detected；
(5) by I2C bus marco display screen, measurement result and single-chip microcontroller working condition are shown.
Communication/the power interface 4 is USB interface, and connection Shi Keyu single-chip microcontroller 3 carries out data communication, and is simultaneously electricity
Source module 6 is powered.Power module 6 is powered by communication/power interface 4, for excitation-sample circuit 2, single-chip microcontroller 3 and display
Screen 5 provides 3.3V, 5V and 9V voltage.The display screen 5 is LCD display.The power module 6 is rechargable power supplies or power supply
Adapter.
The present invention has following technical effect that the present invention can detect a variety of semiconductor gas sensors accurately, in real time
The resistance of element and its variation, output gas concentration information after calculating.The device can be used in conjunction with a variety of semiconductor gas sensors,
Sensor model number is selected according to different target gas, thus the gaseous species that can detecte are extensive, concentration range is big, the scope of application
Extensively, there is very big application value.
Detailed description of the invention
Structure composition figure Fig. 1 of the invention.
Specific embodiment
The following further describes the specific embodiments of the present invention with reference to the drawings, as shown in Figure 1, the fast gas
Quantitative testing device includes following part: semi-conductor gas sensitive material sensor 1, single-chip microcontroller 3, leads to excitation-sample circuit 2
News/power interface 4, display screen 5 and power module 6.
After circuit powers on, single-chip microcontroller 3 reads the configuration parameter of its storage inside first, and starting output frequency is 1kHz's
Pwm signal is used for driving current heating module 203, which is controlled by configuration parameter, can be in 0 to 100% range
It continuously adjusts；Pwm signal directly controls the on-off of pliotron in electric current heating module 203, and then controls semi-conductor gas
The effective power passed through in 1 heating circuit of sensitive material sensor, the final semi-conductor gas sensitive material sensor 1 that controls work
Temperature.Meanwhile single-chip microcontroller 3 can also export three parallel-by-bit digital controlled signals according to configuration parameter, by booster circuit, control small
Multiplexing chip CD4051 in current signal amplification-sampling module 202, according to semi-conductor gas sensitive material sensor 1
Resistance range chooses suitable magnifying power, to guarantee that resistance measurement is accurate.
1 both ends of semi-conductor gas sensitive material sensor by excitation-sample circuit 2 5V voltage drive module 201 it is steady
Chip 79L05 is pressed to guarantee that voltage difference all-the-time stable is 5V, the electric current exported from sensor low-pressure end is turned by two-stage amplifying circuit
0 to 4V voltage signal is turned to, amplified voltage signal is by the AD1115 mould in low current signal amplification-sampling module 202
Number conversion chip sampling, switchs to 14 position digital signals.
The single-chip microcontroller 3 is STM8S series monolithic, with the following functions:
(1) low current signal amplification-sampling module acquisition voltage signal is read by I2C bus；
(2) basis presets value and generates pwm signal control electric current heating module output power；
(3) according to presetting and sensor actual resistance, by numeral output control low current signal amplify-sample mould
The magnifying power of block；Based on multinomial algorithm, it is electric in real time that semi-conductor gas sensitive material sensor is calculated by the voltage signal read
Resistance value calculates gas concentration value to be detected further according to pre-set semi-conductor gas sensitive material working sensor curve；Storage
Deposit the setting of low current signal amplification-sampling module magnifying power, the heating power setting of electric current heating module and semi-conductor gas
The configuration informations such as sensitive material working sensor curve；
(4) UART bus can be forwarded to through CH340 chip by communication/power interface read or rewrite single-chip microcontroller with confidence
Breath, and read low current signal amplification-sampling module output voltage signal value and gas concentration Value Data to be detected；
(5) by I2C bus marco display screen, measurement result and single-chip microcontroller working condition are shown.
Embodiment 1:
In the present embodiment, it is further described so that hydrogen detects as an example:
Use semiconductor nano ZnO material as highly sensitive highly selective in semi-conductor gas sensitive material sensor 1
Hydrogen sensing device.Single-chip microcontroller 3 selects STM8S103F3 single-chip microcontroller, has 16MHz working frequency, using the main power supply electricity of 3.3V
Pressure, with digital input-output interfaces more than I2C bus interface, UART bus interface, PWM output interface and 5 lines.
In the present embodiment, adjustment heated current first makes heating power reach 660mW, and chooses signal magnifying power automatically.
After device resistance stablize after, test and record semi-conductor gas sensitive material element be exposed to 0ppm, 5ppm, 20ppm,
Resistance value in 100ppm, 500ppm hydrogen calibrating gas, is denoted as R0, R1, R2, R3, R4 respectively.R0, R1, R2, R3, R4 is defeated
Enter single-chip microcontroller 3, using fitting of a polynomial working curve and records preservation.Then the present apparatus is placed under test gas atmosphere, is swashed
Encourage-actually measured element resistance value is converted to digital signal and is sent to single-chip microcontroller 3 by sample circuit 2, then by gained signal
After being compared processing with working curve, by I2C bus marco LCD display 5, measurement result and working condition are shown.
Embodiment 2:
In the present embodiment, it is further described so that acetone gas detects as an example:
WO is used in semi-conductor gas sensitive material sensor 13Material, as highly sensitive highly selective acetone sensing
Device.Single-chip microcontroller 3 selects STM8S208 single-chip microcontroller, has 16MHz working frequency, using the main supply voltage of 3.3V, has I2C total
Digital input-output interfaces more than line interface, UART bus interface, PWM output interface and 5 lines.
In the present embodiment, adjustment heated current first makes heating power reach 750mW, and chooses signal magnifying power automatically.
After device resistance stablize after, test and record semi-conductor gas sensitive material element be exposed to 0ppm, 20ppb, 100ppb,
Resistance value in 500ppb, 2ppm, 10ppm acetone calibrating gas, is denoted as R0, R1, R2, R3, R4, R5 respectively.By R0, R1, R2,
R3, R4, R5 input single-chip microcontroller 3, using fitting of a polynomial working curve and record preservation.Then the present apparatus is placed under test gas
In atmosphere, actually measured element resistance value is converted to digital signal and is sent to single-chip microcontroller 3 by excitation-sample circuit 2, then will
After gained signal is compared processing with working curve, by I2C bus marco LCD display 5, measurement result and work are shown
State.
The present invention provides a kind of fast gas suitable for multiple gases to quantify sensing device, implements the technical side
The method of case is not limited to the above embodiments there are many kind.Therefore, without departing from the principle of the present invention, to this
The improvements and modifications that technical solution carries out also should be regarded as protection scope of the present invention.
Claims (8)
1. a kind of fast gas quantitative testing device suitable for multiple gases, it is characterised in that: including semi-conductor gas sensitivity
Material sensors (1), excitation-sample circuit (2), single-chip microcontroller (3), communication/power interface (4), display screen (5) and power module
(6), the semi-conductor gas sensitive material sensor (1) includes semi-conductor gas sensitive material (101), semi-conductor gas sensitivity
Materials for support pedestal (102) and general semiconductor gas sensitive material sensor interface (103), the semi-conductor gas are sensitive
Material (101) is placed or is coated in semi-conductor gas sensitive material support base (102), the support of semi-conductor gas sensitive material
Pedestal (102) is connected on general semiconductor gas sensitive material sensor interface (103), for generating telecommunications to specific gas
Number response；Excitation-the sample circuit (2) includes 5V voltage drive module (201), low current signal amplification-sampling module
(202), electric current heating module (203), the 5V voltage drive module (201) are used to be semi-conductor gas sensitive material sensor
(1) 5V driving voltage is provided, the electric current heating module (203) is used to provide for semi-conductor gas sensitive material sensor (1)
The continuous controllable heated current of power can control the temperature of semi-conductor gas sensitive material (101) in room temperature within the scope of 500 DEG C
Continuously adjustable, the low current signal amplification-sampling module (202) is passed for real-time measurement by semi-conductor gas sensitive material
The electric current of sensor (1), signal amplification factor is controllable, thus the sensor resistance variation of 100 Ω to 25G Ω ranges of measurement, inspection
Survey error < 1%, output delay < 0.2s.
2. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: half
Conductor gas sensitive material sensor (1) is heater-type or directly-heated semiconductor gas sensor element.
3. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 2, it is characterised in that: half
Conductor gas sensitive material sensor (1) is SnO2Material, block SnO2Material, nano ZnO material, nanometer WO3Material, powder
WO3Material.
4. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: institute
Stating single-chip microcontroller (3) is STM8S series monolithic.
5. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: institute
Stating communication/power interface (4) is USB interface, and connection Shi Keyu single-chip microcontroller (3) carries out data communication, and is simultaneously power module
(6) it powers.
6. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: institute
Stating display screen (5) is LCD display.
7. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: electricity
Source module (6) is powered by communication/power interface (4), for mentioning to excitation-sample circuit (2), single-chip microcontroller (3) and display screen (5)
For 3.3V, 5V and 9V voltage.
8. a kind of fast gas quantitative testing device for being suitable for multiple gases according to claim 1, it is characterised in that: institute
Stating power module (6) is rechargable power supplies or power supply adaptor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910540776.5A CN110243877A (en) | 2019-06-21 | 2019-06-21 | A kind of fast gas quantitative testing device suitable for multiple gases |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910540776.5A CN110243877A (en) | 2019-06-21 | 2019-06-21 | A kind of fast gas quantitative testing device suitable for multiple gases |
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| Publication Number | Publication Date |
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| CN110243877A true CN110243877A (en) | 2019-09-17 |
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| CN201910540776.5A Pending CN110243877A (en) | 2019-06-21 | 2019-06-21 | A kind of fast gas quantitative testing device suitable for multiple gases |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111157590A (en) * | 2020-01-21 | 2020-05-15 | 复旦大学 | Semiconductor type carbon monoxide sensor |
| CN112730527A (en) * | 2020-12-18 | 2021-04-30 | 中国科学技术大学 | Gas detection system based on MEMS gas sensor array |
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| CN1257202A (en) * | 1999-12-17 | 2000-06-21 | 中国科学院合肥智能机械研究所 | Selective poison gas alarm |
| CN1892207A (en) * | 2005-07-07 | 2007-01-10 | 中国科学院化学研究所 | Apparatus and method for detecting gas using single sensor |
| CN101545958A (en) * | 2009-05-11 | 2009-09-30 | 吉林大学 | Bidirectional magnetic saturated time difference fluxgate sensor |
| CN106645310A (en) * | 2017-02-05 | 2017-05-10 | 复旦大学 | Dynamic detection system for semiconductor gas sensor |
| CN211927764U (en) * | 2019-06-21 | 2020-11-13 | 启东纳睿新材料科技有限公司 | Quick gaseous quantitative determination device suitable for multiple gas |
-
2019
- 2019-06-21 CN CN201910540776.5A patent/CN110243877A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1257202A (en) * | 1999-12-17 | 2000-06-21 | 中国科学院合肥智能机械研究所 | Selective poison gas alarm |
| CN1892207A (en) * | 2005-07-07 | 2007-01-10 | 中国科学院化学研究所 | Apparatus and method for detecting gas using single sensor |
| CN101545958A (en) * | 2009-05-11 | 2009-09-30 | 吉林大学 | Bidirectional magnetic saturated time difference fluxgate sensor |
| CN106645310A (en) * | 2017-02-05 | 2017-05-10 | 复旦大学 | Dynamic detection system for semiconductor gas sensor |
| CN211927764U (en) * | 2019-06-21 | 2020-11-13 | 启东纳睿新材料科技有限公司 | Quick gaseous quantitative determination device suitable for multiple gas |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111157590A (en) * | 2020-01-21 | 2020-05-15 | 复旦大学 | Semiconductor type carbon monoxide sensor |
| CN111157590B (en) * | 2020-01-21 | 2023-03-07 | 复旦大学 | Semiconductor type carbon monoxide sensor |
| CN112730527A (en) * | 2020-12-18 | 2021-04-30 | 中国科学技术大学 | Gas detection system based on MEMS gas sensor array |
| CN112730527B (en) * | 2020-12-18 | 2022-05-13 | 中国科学技术大学 | Gas detection system based on MEMS gas sensor array |
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