Gas sensitive sensor testing system capable of rapidly switching testing atmosphere based on dynamic gas distribution

Abstract

The invention relates to a dynamic gas distribution-based gas sensitive sensor test system capable of rapidly switching test atmosphere, which belongs to the crossing field of sensor and gas sensitive element performance test, and comprises a dynamic gas distribution test device, a sensing signal acquisition gas chamber, a network switch and a computer. The dynamic gas distribution testing device is used for mixing background gas and hydrogen and continuously and stably outputting to-be-tested gas with set concentration to the sensing signal acquisition gas chamber; the sensing signal acquisition gas chamber is used for quickly switching gas to be tested and background gas, acquiring a response signal of the gas sensor and feeding back the signal to the dynamic gas distribution testing device; and the computer is used for monitoring, recording and storing response signals of the gas sensitive sensor on line. According to the invention, a mode of dynamic gas distribution and rapid test gas switching is adopted, so that the speed of the hydrogen concentration in the sensing signal acquisition gas chamber reaching the set concentration and the stability of the concentration can be greatly improved, thereby realizing accurate evaluation of various performance parameters of the sensor.

Description

Technical Field

[0001] The invention relates to the technical field of gas sensor performance testing, and in particular to a gas sensor testing system for rapidly switching test atmospheres based on dynamic gas distribution. Background Art

[0002] Hydrogen is considered to be the greenest and most environmentally friendly energy source and an ideal energy source for the transition to a low-emission or zero-emission global energy system. However, hydrogen itself is a flammable and explosive gas. Its colorless and odorless properties make it difficult to detect when hydrogen leaks. Therefore, hydrogen sensors are needed to monitor hydrogen leaks during hydrogen production, transportation, storage, and application (hydrogen fuel cell vehicles) to ensure hydrogen safety. In the research of hydrogen sensors, test devices that can accurately evaluate the performance of hydrogen sensors / gas-sensitive materials play an indispensable role.

[0003] At present, there are only a few commercial sensor test devices on the market. Among the existing hydrogen sensor test devices, patent CN114414647A provides an electrochemical gas sensor performance test system. The device adopts a static gas distribution method. Due to the low density of hydrogen (density: hydrogen 0.0899g / cm 3 、Nitrogen 1.2506g / cm 3 、Oxygen 1.429g / cm 3 ) There is stratification in the mixed gas, which causes uneven concentration distribution in the test gas chamber and slow gas mixing. Although a small fan is installed in the test gas chamber to increase gas disturbance to improve the gas mixing speed and uniformity, there is still a problem of long response time (greater than 20 seconds) in the test results; Patent CN116678997A introduces a multifunctional hydrogen sensor evaluation test device, which can measure temperature and humidity, interfering gas, etc., and can more comprehensively evaluate the sensor performance, but the device also uses static gas distribution and small fan disturbance, so the test electrochemical hydrogen sensor response time is as long as 90 seconds ; Patent CN116087277A invented a test method and test device for a light-excited semiconductor gas sensor, which solves the problem of the simultaneous promotion and inhibition of the existing (continuous) light excitation on the semiconductor gas sensor, and improves the response sensitivity of the sensor test, but the static gas distribution method still has the problem of long measured response time (greater than 60 seconds); Patent CN108918602A provides a semiconductor gas sensor performance test system and test method, which can realize automatic gas distribution and rapid testing process through computer control, but its test response time is greater than 30 seconds.

[0004] In summary, the hydrogen sensor test device has problems such as uneven hydrogen stratification concentration distribution and long gas mixing time during the gas distribution process, which leads to large data errors and long response time in the test results of the hydrogen sensor. It cannot accurately evaluate the various performance parameters of the gas sensor, which limits the research and application of the gas sensor. Therefore, there is an urgent need for a gas distribution test device with uniform concentration of the gas to be tested, fast mixing, and fast switching between background gas and test gas. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a gas sensor testing system based on dynamic gas distribution and rapid switching of test atmosphere in response to the above-mentioned deficiencies in the prior art. The system can use a computer to control the mass flow controller in the dynamic gas distribution testing device to automatically prepare the test gas of a set concentration, and continuously and stably deliver it to the sensor signal acquisition chamber in a dynamic manner, thereby overcoming the problems of hydrogen stratification, uneven concentration distribution and long gas mixing time in static gas distribution, and combining the test gas and background gas rapid switching technology to greatly improve the test accuracy of various performance parameters of the sensor.

[0006] The technical means adopted by the present invention are as follows:

[0007] A gas sensor test system for fast switching test atmosphere based on dynamic gas distribution, comprising: a dynamic gas distribution test device, a sensor signal collection chamber, a network switch and a computer;

[0008] The background gas cylinder is connected to the air inlet of the dynamic gas distribution device through gas pipeline I and gas pipeline II, and the hydrogen cylinder is connected to the air inlet of the dynamic gas distribution device through gas pipeline IV. The dynamic gas distribution test device dilutes the hydrogen into a hydrogen mixture of set concentration according to the instructions of the computer, and the diluted hydrogen mixture is continuously and stably transported to the sensor signal collection chamber through gas pipeline VI. The signal generated by the sensor arranged in the sensor plug-in plate in the test gas is transmitted to the dynamic gas distribution test device through the data transmission line, and then the test data is transmitted to the computer through the network switch.

[0009] Furthermore, the dynamic gas distribution test device includes: a shell, one side of which is provided with a background gas inlet and a hydrogen inlet, the other side of which is provided with a tail exhaust port, a mixed gas outlet, a network interface, and a data transmission interface, and the front end face is provided with an indicator light and a switch. The interior of the dynamic gas distribution test device also includes: a number of mass flow controllers and isolated explosion-proof components.

[0010] Furthermore, the sensor signal collection air chamber includes: a front end door, a front end plate, an upper end plate, a side end plate I, a side end plate II, a rear end plate and a sensor plug-in plate.

[0011] Furthermore, the front end panel is provided with a mixed gas inlet, a background gas inlet and a test gas switching lever, wherein the test gas switching lever is used to quickly switch the test atmosphere of the sensor between the background gas and the gas to be tested, so as to more accurately test the response time and recovery time of the hydrogen sensor.

[0012] Furthermore, one of the side surfaces of the upper end plate is provided with hinge hinge I, hinge hinge II, and hinge hinge III for opening / closing the upper end plate; the other side surface is provided with a buckle for fastening and fixing the upper end plate; a handle is provided in the middle of the end surface where the buckle is located to assist the opening / closing operation of the upper end plate.

[0013] Furthermore, a partition is disposed inside each of the side end plate I and the side end plate II, namely, partition I and partition II, and the partition is used to fix the sensor plug-in plate and divide the gas channel of the hydrogen mixed gas / background gas.

[0014] Furthermore, the rear end plate is provided with a mixed gas outlet and a background gas outlet.

[0015] Furthermore, the hydrogen concentration instruction set in the computer software operation interface is transmitted to the network switch by the network cable II, and then transmitted to the dynamic gas distribution test device by the network cable I. The dynamic gas distribution test device controls a number of hydrogen and air mass flow controllers to prepare a mixed gas of the set concentration according to the instruction. The mixed gas is transported to the sensor signal collection chamber through the gas pipeline VI. The response signal generated by the sensor in the chamber under the mixed gas condition is transmitted to the dynamic gas distribution test device via the data transmission line, and then transmitted to the network switch by the network cable I, and transmitted to the computer end via the network cable II for data monitoring, recording and storage.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The present invention utilizes an automated testing procedure to simplify the testing process and reduce the investment of manpower and time; it utilizes the assistance of dynamic gas distribution and test gas rapid switching technology to improve the reliability of sensor parameters obtained from the test, thereby facilitating the research and development, promotion and application of gas sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 The present invention is a schematic structural diagram of a gas sensor testing system for rapidly switching test gases based on dynamic gas distribution.

[0020] Figure 2 This is a schematic diagram of the structure of the sensor signal collection air chamber of the present invention.

[0021] Figure 3 This is a response curve obtained by testing an electrochemical hydrogen sensor under a condition where the hydrogen concentration is set to 1000 ppm using a gas sensor testing system for fast switching of test gas based on dynamic gas distribution in an embodiment of the present invention.

[0022] Figure 4 It is the response time obtained by testing an electrochemical hydrogen sensor under a condition of a set hydrogen concentration of 1000 ppm using a gas sensor testing system for fast switching of test gas based on dynamic gas distribution in an embodiment of the present invention.

[0023] Figure 5 It is the recovery time obtained by testing an electrochemical hydrogen sensor under a condition of a set hydrogen concentration of 1000 ppm using a gas sensor testing system for fast switching of test gas based on dynamic gas distribution in an embodiment of the present invention.

[0024] Among them, 101 is a background gas cylinder; 102 is a hydrogen cylinder; 201 is a gas pipeline I; 202 is a gas pipeline II; 203 is a gas pipeline III; 204 is a gas pipeline IV; 205 is a gas pipeline V; 206 is a gas pipeline VI; 207 is a gas pipeline VII; 208 is a gas pipeline VIII; 3 is a dynamic gas distribution test device; 301 is a background gas inlet; 302 is a hydrogen inlet; 303 is an indicator light; 304 is a switch; 305 is a tail exhaust port; 306 is a mixed gas outlet; 307 is a network interface; 308 is a gas chamber data transmission interface I; 309 is a shell; 4 is a sensor signal acquisition chamber; 401 is a mixed gas inlet; 402 is a background gas inlet; 4 03 is the test gas switching operating lever; 404 is the front door; 405 is the front plate; 406 is the upper plate; 407 is the side plate I; 408 is the bottom plate; 409 is the side plate II; 410 is the rear plate; 411 is the partition I; 412 is the partition II; 413 is the sensor plug-in plate; 414 is the sensor plug-in plate; 415 is the hinge I; 416 is the hinge II; 417 is the hinge III; 418 is the handle; 419 is the buckle; 420 is the power switch; 421 is the mixed gas outlet; 422 is the background gas outlet; 423 is the gas chamber data transmission interface II; 5 is the data transmission line; 6 is the network switch; 601 is the network cable I; 602 is the network cable II; 7 is the computer. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] like Figure 1 , 2 As shown, a gas sensor test system for fast switching test gas based on dynamic gas distribution includes a dynamic gas distribution test device 3, a sensor signal acquisition chamber 4, a network switch 6 and a computer 7. The background gas cylinder 101 (air or nitrogen) is connected to the background gas inlet 301 of the dynamic gas distribution test device 3 through gas pipelines I201 and II202, and the hydrogen cylinder 102 is connected to the hydrogen gas inlet 302 of the dynamic gas distribution test device 3 through gas pipelines IV204. The diluted mixed gas to be tested is continuously and stably transported to the sensor signal acquisition chamber 4 through gas pipelines VI206. The signal generated by the sensor installed in the sensor plug-in plate 414 in the test gas is transmitted to the dynamic gas distribution test device 3 through the data transmission line 5, and then the test data is transmitted to the computer 7 through the network switch 6.

[0028] The dynamic gas distribution test device 3 includes: a shell 309, a background gas inlet 301 and a hydrogen gas inlet 302 are arranged on one side end plate, a tail exhaust port 305, a mixed gas outlet 306, a network interface 307 and a gas chamber data transmission interface 308 are arranged on the other side end plate, and an indicator light 303 and a switch 304 are arranged on the front end plate. The interior also includes a number of mass flow controllers, isolated explosion-proof components, etc., which are used to safely mix flammable and explosive gases (hydrogen, etc.) with background gases (air, etc.) to a set concentration, and continuously and smoothly transport them from the outlet 306 to the sensor signal acquisition chamber 4 for collecting sensor response signals.

[0029] The sensing signal acquisition chamber 4 includes: a front door 404, a front plate 405, an upper plate 406, a side plate I407, a side plate II409, a rear plate 410 and a sensor insert 413. The front plate 405 is provided with a mixed gas inlet 401, a background gas inlet 402 and a test gas switching lever 403, wherein the test gas switching lever 403 is used to quickly switch the test atmosphere of the sensor between the background gas (air or nitrogen) and the gas to be tested (hydrogen mixed gas), so as to more accurately test the response time and recovery time of the hydrogen sensor. A hinge I415, a hinge II416, and a hinge III417 are provided on one side of the upper end plate 406 for opening / closing the upper end plate 406; a buckle 419 is provided on the other side for fastening and fixing the upper end plate 406; a handle 418 is provided in the middle of the end surface where the buckle 419 is located for assisting the opening / closing operation of the upper end plate 406. A partition is provided on the inner side of the side end plate I407 and the side end plate II409, which are respectively a partition I411 and a partition II412, and the partition is used to fix the sensor plug plate 414 and the gas channel for dividing the hydrogen mixed gas / background gas.

[0030] Preferably, in the present application, the materials of the front door 404, the front panel 405, the upper panel 406, the side panel I407, the bottom panel 408, the side panel II409, the rear panel 410, the partition I411, the partition II412, and the handle 418 include but are not limited to stainless steel, glass, ceramics, polymethyl methacrylate, etc.

[0031] The hydrogen concentration instruction set in the software operation interface of computer 7 is transmitted to the network switch 6 by network cable II602, and then transmitted to the dynamic gas distribution test device 3 by network cable I601. The dynamic gas distribution test device 3 controls a number of hydrogen and air mass flow controllers to prepare a mixed gas of set concentration according to the instruction. The mixed gas is transported to the sensor signal collection chamber 4 through the gas pipeline VI206. The response signal of the sensor under the mixed atmosphere is fed back to the dynamic gas distribution test device 3 through the data transmission line 5, and then transmitted to the network switch 6 by network cable I601, and then transported to the computer 7 through network cable II602 for online data monitoring, recording and storage.

[0032] Select an electrochemical hydrogen sensor, choose a corresponding type of sensor signal acquisition chamber 4, and install the sensor in the chamber; open the main valves, voltage dividers and ball valves of the air cylinder 101 and the hydrogen cylinder 102, and deliver hydrogen, air and other gases required for the test to the dynamic gas distribution test device 3; set the test parameters and process on the computer 7, click "Start", and the dynamic gas distribution test device 3 can prepare the mixed gas to be tested with the set concentration according to the instructions, and the mixed gas is delivered to the sensor signal acquisition chamber through the gas pipeline VI206. At the same time, the data transmission line 5 transmits the response signal fed back by the sensor signal acquisition chamber 4 to the computer 7; after the test program is completed, the computer saves the data, closes the main valve, voltage divider and ball valve of the gas cylinder, and completes the test.

[0033] Figure 3 The gas sensor test system of the present invention, which is based on dynamic gas distribution and fast switching of test gas, tests an electrochemical hydrogen sensor under the condition of a set hydrogen concentration of 1000ppm, and the response curve is obtained, and the response current is 4.88 microamperes.

[0034] Figure 4 The response time of the gas sensor test system based on the dynamic gas distribution and fast switching test gas of the present invention is 0.4 seconds when the electrochemical hydrogen sensor is tested under the condition of setting the hydrogen concentration to 1000ppm.

[0035] Figure 5 The recovery time is 0.4 seconds when the gas sensor test system of the present invention, which uses dynamic gas distribution to quickly switch test gas, tests an electrochemical hydrogen sensor under the condition of a set hydrogen concentration of 1000 ppm.

[0036] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments. In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gas sensor test system based on dynamic gas distribution and rapid switching of test atmosphere, characterized in that: include: Dynamic gas distribution test device (3), sensor signal collection chamber (4), network switch (6) and computer (7); The background gas cylinder (101) is connected to the gas inlet (301) of the dynamic gas distribution device through gas pipelines I (201) and II (202); the hydrogen cylinder (102) is connected to the gas inlet (302) of the dynamic gas distribution device through gas pipelines IV (204); the dynamic gas distribution test device (3) dilutes the hydrogen into a hydrogen mixed gas of a set concentration according to the instructions of the computer (7); the diluted hydrogen mixed gas is continuously and stably transported to the sensor signal collection chamber (4) through gas pipelines VI (206); the signal generated by the sensor arranged in the sensor plug-in plate (414) in the test gas is transmitted to the dynamic gas distribution test device (3) through the data transmission line (5); and the test data is then transmitted to the computer (7) through the network switch (6).

2. The gas sensor testing system for rapidly switching the test atmosphere based on dynamic gas distribution according to claim 1 is characterized in that: The dynamic gas distribution test device (3) comprises: a housing (309), one side of which is provided with a background gas inlet (301) and a hydrogen gas inlet (302), and the other side of which is provided with a tail outlet (305), a mixed gas outlet (306), a network interface (307), a data transmission interface (308), and a front end surface provided with an indicator light (303) and a switch (304). The interior of the dynamic gas distribution test device (3) also includes: a plurality of mass flow controllers and isolated explosion-proof components.

3. The gas sensor testing system for rapidly switching test atmosphere based on dynamic gas distribution according to claim 1 is characterized in that: The sensor signal collection air chamber (4) comprises: a front end door (404), a front end plate (405), an upper end plate (406), a side end plate I (407), a side end plate II (409), a rear end plate (410) and a sensor plug-in plate (414).

4. The gas sensor testing system for rapidly switching the test atmosphere based on dynamic gas distribution according to claim 3 is characterized in that: The front end plate (405) is provided with a mixed gas inlet (401), a background gas inlet (402) and a test gas switching operating lever (403), wherein the test gas switching operating lever (403) is used to quickly switch the test atmosphere of the sensor between the background gas and the gas to be tested, so as to more accurately test the response time and recovery time of the hydrogen sensor.

5. A gas sensor testing system for fast switching of test gas based on dynamic gas distribution according to claim 3, characterized in that: One side surface of the upper end plate (406) is provided with hinge hinge I (415), hinge hinge II (416), and hinge hinge III (417) for opening / closing the upper end plate (406); the other side surface is provided with a buckle (419) for fastening and fixing the upper end plate (406); a handle (418) is provided in the middle of the end surface where the buckle (419) is located to assist the opening / closing operation of the upper end plate (406).

6. A gas sensor testing system for rapidly switching test atmosphere based on dynamic gas distribution according to claim 3, characterized in that: A partition is disposed on the inner side of each of the side end plates I (407) and II (409), which are partition I (411) and partition II (412), respectively. The partition is used to fix the sensor plug plate (414) and to separate the gas channel of the hydrogen mixed gas / background gas.

7. A gas sensor testing system for rapidly switching test atmosphere based on dynamic gas distribution according to claim 3, characterized in that: The rear end plate (410) is provided with a mixed gas outlet (421) and a background gas outlet (422).

8. A gas sensor testing system for fast switching of test gas based on dynamic gas distribution according to claim 1, characterized in that: The hydrogen concentration instruction set in the software operation interface of the computer (7) is transmitted to the network switch (6) via the network cable II (602), and then transmitted to the dynamic gas distribution test device (3) via the network cable I (601). The dynamic gas distribution test device (3) controls a plurality of hydrogen and air mass flow controllers to prepare a mixed gas of the set concentration according to the instruction. The mixed gas is transported to the sensor signal collection chamber (4) through the gas pipeline VI (206). The response signal generated by the sensor in the chamber under the mixed gas condition is transmitted to the dynamic gas distribution test device (3) via the data transmission line (5), and then transmitted to the network switch (6) via the network cable I (601), and then transmitted to the computer (7) via the network cable II (602) for data monitoring, recording and storage.

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