Hydrogen concentration detection method, device and system

Abstract

The application discloses a hydrogen concentration detection method, device and system. The method is executed by a hydrogen concentration detection device, comprising a metal palladium sensor unit, a heating unit, a flow rate detection unit and a control unit, wherein the metal palladium sensor unit, the heating unit, the flow rate detection unit and the control unit are in communication connection, the hydrogen concentration detection device is arranged in a gas flow pipeline, and the method comprises the following steps: acquiring a current gas flow rate value in the gas flow pipeline through the flow rate detection unit, and sending the current gas flow rate value to the control unit; controlling the heating unit to heat the metal palladium sensor unit according to the current gas flow rate value through the control unit; acquiring a resistance change value of the metal palladium sensor unit through the control unit; and determining a hydrogen concentration value in the gas flow pipeline according to the resistance change value through the control unit. The scheme can make the hydrogen detection result more stable.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and in particular to a method, apparatus and system for detecting hydrogen concentration. Background Technology

[0002] Hydrogen is a colorless, odorless, and explosive gas. In some scenarios where large amounts of hydrogen are used, it is necessary to prevent hydrogen leaks to ensure personnel safety. Therefore, it is necessary to detect the concentration of hydrogen in the air in specific locations to serve as an early warning system.

[0003] Currently, the most commonly used method for detecting hydrogen concentration is a hydrogen concentration sensor that uses palladium as an electrode. When this sensor adsorbs hydrogen, its resistance changes, and the hydrogen concentration in the air can be determined by calculating the functional relationship between the resistance change and the hydrogen concentration.

[0004] However, the resistivity of palladium is affected by ambient temperature. Fluctuations in ambient temperature can affect the sensor's detection, leading to unstable results. Therefore, a method is needed to make hydrogen detection results more stable. Summary of the Invention

[0005] This invention provides a method, apparatus, and system for detecting hydrogen concentration to solve the problem of unstable hydrogen concentration detection results when the ambient temperature fluctuates.

[0006] According to one aspect of the present invention, a method for detecting hydrogen concentration is provided, the method being executed by a hydrogen concentration detection device, the hydrogen concentration detection device comprising a palladium metal sensor unit, a heating unit, a flow rate detection unit, and a control unit, wherein the palladium metal sensor unit, the heating unit, and the flow rate detection unit are communicatively connected to the control unit, and the hydrogen concentration detection device is disposed within a gas flow pipeline, the method comprising:

[0007] The flow rate detection unit acquires the current gas flow rate value in the gas flow pipe and sends the current gas flow rate value to the control unit.

[0008] The control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate.

[0009] The resistance change value of the palladium sensor unit is obtained through the control unit;

[0010] The control unit determines the hydrogen concentration in the gas flow pipe based on the resistance change value.

[0011] Optionally, the heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire, wherein the first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the first surface and the second surface of the palladium metal sensor unit, wherein the first surface is the surface of the palladium metal sensor unit away from the wall of the gas flow pipe, and the second surface is the surface of the palladium metal sensor unit close to the wall of the gas flow pipe, and the supplementary heating wire is disposed inside the palladium metal sensor unit;

[0012] Accordingly, the control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate value, including:

[0013] The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value.

[0014] The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value.

[0015] The palladium sensor unit is heated by the first heating wire, the second heating wire, and the supplemental heating wire.

[0016] Optionally, the control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value, including:

[0017] The control unit calculates the compensation temperature value of the current heating wire using the following heating wire formula, wherein the formula includes:

[0018] T＝I 2 ×a×W×L×H×(K+bN) ;

[0019] Where T is the compensation temperature value of the current heating line, I is the target control current value, W is the width of the current heating line, L is the length of the current heating line, K is the temperature setting coefficient in the gas flow pipe, and N is the increase between the current gas flow rate and the preset gas flow rate in the gas flow pipe; the current heating line is any one of the first heating line, the second heating line, and the compensation heating line; a is the first temperature coefficient, and b is the second temperature coefficient.

[0020] Adjust the current temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire to the compensation temperature value.

[0021] Optionally, a reference palladium sensor unit is provided in an insulated and enclosed manner at a symmetrical position to the palladium sensor unit in the gas flow pipeline.

[0022] Accordingly, after obtaining the resistance change value of the palladium sensor unit through the control unit, the method further includes:

[0023] Determine the reference resistance value of the reference palladium sensor unit;

[0024] The resistance change value is obtained by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

[0025] Optionally, obtaining the resistance change value of the palladium sensor unit through the control unit includes:

[0026] The control unit determines a preset function representing the change in resistance and the change in hydrogen concentration.

[0027] The hydrogen concentration value is obtained by substituting the resistance change value into the change function.

[0028] According to another aspect of the present invention, a hydrogen concentration detection device is provided, comprising: a control unit, a palladium metal sensor unit, a heating unit, and a flow rate detection unit; wherein the palladium metal sensor unit, the heating unit, and the flow rate detection unit are disposed in a gas flow pipeline, and the hydrogen concentration detection device is communicatively connected to the palladium metal sensor unit, the heating unit, and the flow rate detection unit;

[0029] The flow rate detection unit is used to acquire the current gas flow rate value in the gas flow pipe and send the current gas flow rate value to the control unit;

[0030] The control unit is configured to control the heating unit to heat the palladium sensor unit according to the current gas flow rate; obtain the resistance change value of the palladium sensor unit; and determine the hydrogen concentration value in the gas flow pipeline based on the resistance change value.

[0031] According to another aspect of the present invention, a hydrogen concentration detection system is provided, comprising a hydrogen concentration detection device and a gas flow pipeline; the hydrogen concentration detection device is disposed within the gas flow pipeline;

[0032] The hydrogen concentration detection device is used to perform the hydrogen concentration detection method according to any one of claims 1-6.

[0033] Optionally, the system further includes: a reference metal palladium sensor unit;

[0034] The hydrogen concentration detection device is used to determine the reference resistance value of the reference palladium sensor unit.

[0035] The resistance change value is obtained by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

[0036] Optionally, the heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire, wherein the first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the upper and lower surfaces of the palladium sensor unit, and the supplementary heating wire is disposed inside the palladium sensor unit.

[0037] Optionally, it may further include: a thermal insulation unit;

[0038] The heat insulation unit is disposed on the inner wall and / or outer wall of the gas flow duct.

[0039] The technical solution of this invention, by setting a heating unit to heat the palladium sensor unit and controlling the temperature of the heating unit according to the detection result of the flow rate detection unit, keeps the palladium sensor unit in a relatively constant temperature environment, thus solving the problem that the detection result of the palladium sensor unit fluctuates greatly with changes in ambient temperature, and achieving the beneficial effect of making the hydrogen concentration detection result more stable.

[0040] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a flowchart of a hydrogen concentration detection method provided in Embodiment 1 of the present invention;

[0043] Figure 2 This is a flowchart of a method for heating a palladium sensor unit according to Embodiment 2 of the present invention;

[0044] Figure 3 This is a schematic diagram of a heating unit applicable to Embodiment 2 of the present invention;

[0045] Figure 4This is a flowchart of a method for determining the resistance change value according to Embodiment 3 of the present invention;

[0046] Figure 5 This is a schematic diagram of the structure of a hydrogen concentration detection device according to Embodiment 4 of the present invention;

[0047] Figure 6 This is a schematic diagram of a hydrogen concentration detection system provided in Embodiment 5 of the present invention. Detailed Implementation

[0048] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0049] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0050] Example 1

[0051] Figure 1 This is a flowchart of a hydrogen concentration detection method provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where the hydrogen concentration detection results are unstable due to fluctuations in ambient temperature. The method can be executed by a hydrogen concentration detection device, which includes a palladium metal sensor unit, a heating unit, a flow rate detection unit, and a control unit. The palladium metal sensor unit, heating unit, and flow rate detection unit are communicatively connected to the control unit. The hydrogen concentration detection device is installed within a gas flow pipeline. Figure 1 As shown, the method includes:

[0052] S110. Obtain the current gas flow rate value in the gas flow pipe through the flow rate detection unit, and send the current gas flow rate value to the control unit.

[0053] Among them, the gas flow pipeline is a channel for gas flow in scenarios where hydrogen leakage may occur. The flow rate detection unit can be set in the gas flow pipeline. When the gas flows in the pipeline, since the gas flow direction is only along one direction of the pipeline, the flow rate value of the gas can be determined by the flow rate detection unit.

[0054] S120. The control unit controls the heating unit to heat the palladium sensor unit according to the current gas flow rate value.

[0055] The palladium sensor unit uses palladium as its electrode to detect the concentration of hydrogen in the air. When it adsorbs hydrogen, the hydrogen releases electrons, which combine with oxygen ions in the chemisorption layer, causing a change in carrier concentration, i.e., a change in resistance. The real-time hydrogen concentration is then calculated based on this change. However, besides the significant change in resistance when hydrogen adheres, palladium is also sensitive to ambient temperature. Therefore, the palladium sensor unit needs to operate in a relatively stable temperature environment to eliminate the influence of ambient temperature and improve its measurement accuracy. The heating unit, under the control of the control unit, maintains a relatively stable ambient temperature for the palladium sensor unit. Since gas is not a static model but a constantly diffusing model, for example, when the gas flow rate increases, it carries away some heat from the environment, affecting the detection performance of the palladium sensor unit. Therefore, the heating unit is controlled to compensate for this by adjusting the heating based on the current gas flow rate. For example, the heating temperature is increased when the current gas flow rate increases, thus stabilizing the ambient temperature within a reasonable range so as not to affect the detection results of the palladium sensor unit.

[0056] S130. Obtain the resistance change value of the palladium sensor unit through the control unit.

[0057] As mentioned earlier, when palladium comes into contact with hydrogen, the hydrogen releases electrons, which combine with oxygen ions in the chemisorption layer, causing a change in the carrier concentration and a change in the resistance of palladium. The change in resistance is the degree of change in the resistance of palladium.

[0058] S140. The control unit determines the hydrogen concentration in the gas flow pipe based on the resistance change value.

[0059] The change in resistance of palladium is related to the change in hydrogen concentration, and the two are related as a function. Therefore, the hydrogen concentration can be calculated based on the functional relationship between the change in resistance and the hydrogen concentration.

[0060] The technical solution of this invention, by setting a heating unit to heat the palladium sensor unit and controlling the temperature of the heating unit according to the detection result of the flow rate detection unit, keeps the palladium sensor unit in a relatively constant temperature environment, thus solving the problem that the detection result of the palladium sensor unit fluctuates greatly with changes in ambient temperature, and achieving the beneficial effect of making the hydrogen concentration detection result more stable.

[0061] Example 2

[0062] Figure 2 This is a flowchart of a heating method for a palladium sensor unit according to Embodiment 2 of the present invention. This embodiment is an optimization based on Embodiment 1. Specifically, the optimization is as follows: the heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire. The first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the first surface and the second surface of the palladium sensor unit. The first surface is the surface of the palladium sensor unit away from the wall of the gas flow pipe, and the second surface is the surface of the palladium sensor unit close to the wall of the gas flow pipe. The supplementary heating wire is disposed inside the palladium sensor unit.

[0063] Accordingly, the control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate value, including:

[0064] The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value.

[0065] The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value.

[0066] The palladium sensor unit is heated by the first heating wire, the second heating wire, and the supplemental heating wire.

[0067] like Figure 2 As shown, the method includes the following steps:

[0068] S210. The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value.

[0069] Since the gas carries away heat from the detection environment when it flows, temperature compensation is required through the heating unit based on the gas flow rate in order to stabilize the ambient temperature within a certain range. One feasible method is to adjust the heating temperature of the heating unit by adjusting the control current value of the heating unit. The target control current value is the current value for adjusting the heating temperature of the heating unit based on the current gas flow rate, thereby achieving temperature compensation based on the gas flow rate.

[0070] S220. The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value.

[0071] The heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire. Figure 3 This is a schematic diagram of a heating unit. A first heating wire 310 and a second heating wire 320 are respectively disposed on the first and second surfaces of the palladium sensor unit 330 along the arrangement trajectory of the palladium sensor unit. A supplementary heating wire 340 is disposed inside the palladium sensor unit.

[0072] The first and second heating wires ensure that the heat on both surfaces of the palladium sensor unit is not reduced by airflow and effectively heat both surfaces. The supplementary heating wire is located inside the electrodes of the palladium sensor unit, heating it internally. To increase the contact area between the palladium sensor unit and the gas, and improve detection accuracy, the palladium sensor unit is serrated. Optionally, the first and second heating wires are also serrated to increase the heating wire range.

[0073] S230. The palladium sensor unit is heated by the first heating wire, the second heating wire and the supplementary heating wire.

[0074] Optionally, the control unit can be connected to three constant current sources, which are respectively connected to the first heating wire, the second heating wire, and the supplementary heating wire. The control unit controls the current of the constant current sources, thereby controlling the first heating wire, the second heating wire, and the supplementary heating wire to heat the palladium sensor unit.

[0075] In this embodiment of the application, optionally, the control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value, including:

[0076] The control unit calculates the compensation temperature value of the current heating wire using the following heating wire formula, wherein the formula includes:

[0077] T＝ I2×a×W×L×H×(K+bN) ;

[0078] Wherein, T is the compensation temperature value of the current heating line, I is the target control current value, W is the width of the current heating line, L is the length of the current heating line, K is the temperature setting coefficient in the gas flow pipe, and N is the increase between the current gas flow rate value and the preset gas flow rate value in the gas flow pipe; the current heating line is any one of the first heating line, the second heating line, and the compensation heating line; a is the first temperature coefficient, and b is the second temperature coefficient.

[0079] Adjust the current temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire to the compensation temperature value.

[0080] Where N is in m / s, it is a parameter obtained based on the air velocity relative to the space of the gas flow duct; K is the temperature setting coefficient of the enclosed space gas flow duct, which can be 20-60, the first temperature coefficient 'a' can be 5.56, and the second temperature coefficient 'b' can be 1.3. Since the first and second heating wires can be set as serrated, the length value L will be greater than that of the supplementary heating wire in the calculation. The compensation temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire should be slightly greater than the ambient temperature.

[0081] Example 3

[0082] Figure 4 This is a flowchart of a method for determining a resistance change value provided in Embodiment 3 of the present invention. This embodiment is a further optimization of the above embodiment, specifically: in the gas flow pipeline, a reference palladium sensor unit is provided in an insulated and sealed manner at a symmetrical position to the palladium sensor unit;

[0083] Accordingly, after obtaining the resistance change value of the palladium sensor unit through the control unit, the method further includes:

[0084] Determine the reference resistance value of the reference palladium sensor unit;

[0085] The resistance change value is obtained by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

[0086] like Figure 4 As shown, the method includes:

[0087] S410. Determine the reference resistance value of the reference palladium sensor unit.

[0088] The reference resistance value is the resistance value of the reference palladium sensor unit, which serves as a reference object. When the palladium sensor unit detects hydrogen concentration, the reference palladium sensor unit is insulated and sealed in the gas flow pipe and does not detect hydrogen concentration. Instead, it is used to further eliminate environmental interference to the palladium sensor unit.

[0089] S420. Subtract the reference resistance value from the actual resistance change value of the palladium sensor unit to obtain the resistance change value.

[0090] The hydrogen concentration value is obtained by the resistance change of the palladium metal sensor unit. Even though heating the palladium metal sensor unit can greatly reduce the influence of ambient temperature on the detection results, there will still be some error. Therefore, by subtracting the reference resistance value from the actual resistance change value of the palladium metal sensor unit, we can obtain the actual resistance change value of the palladium metal sensor unit due to the hydrogen concentration, making the detection of hydrogen concentration more accurate.

[0091] In one embodiment of the present invention, optionally, obtaining the resistance change value of the palladium sensor unit through the control unit includes:

[0092] The control unit determines a preset function representing the change in resistance and the change in hydrogen concentration.

[0093] The hydrogen concentration value is obtained by substituting the resistance change value into the change function.

[0094] Example 4

[0095] Figure 5 This is a schematic diagram of a hydrogen concentration detection device provided in Embodiment 4 of the present invention. Figure 5 As shown, the device includes: a control unit 510, a palladium sensor unit 520, a heating unit 530, and a flow rate detection unit 540; the palladium sensor unit 520, the heating unit 530, and the flow rate detection unit 540 are disposed in a gas flow pipeline, and the hydrogen concentration detection device is communicatively connected to the palladium sensor unit 520, the heating unit 530, and the flow rate detection unit 540;

[0096] The flow rate detection unit 540 is used to acquire the current gas flow rate value in the gas flow pipe and send the current gas flow rate value to the control unit 510;

[0097] The control unit 510 is used to control the heating unit 530 to heat the palladium sensor unit 520 according to the current gas flow rate; to obtain the resistance change value of the palladium sensor unit 520; and to determine the hydrogen concentration value in the gas flow pipeline according to the resistance change value.

[0098] Optionally, the heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire, wherein the first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the first surface and the second surface of the palladium metal sensor unit, wherein the first surface is the surface of the palladium metal sensor unit away from the wall of the gas flow pipe, and the second surface is the surface of the palladium metal sensor unit close to the wall of the gas flow pipe, and the supplementary heating wire is disposed inside the palladium metal sensor unit;

[0099] Accordingly, when the control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate value, it specifically performs the following:

[0100] The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value.

[0101] The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value.

[0102] The palladium sensor unit is heated by the first heating wire, the second heating wire, and the supplemental heating wire.

[0103] Optionally, when the control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire according to the target control current value, it specifically performs the following:

[0104] The control unit calculates the compensation temperature value of the current heating wire using the following heating wire formula, wherein the formula includes:

[0105] T ＝ I2×a×W×L×H×(K+bN) ;

[0106] Where T is the compensation temperature value of the current heating line, I is the target control current value, W is the width of the current heating line, L is the length of the current heating line, K is the temperature setting coefficient in the gas flow pipe, and N is the increase between the current gas flow rate and the preset gas flow rate in the gas flow pipe; the current heating line is any one of the first heating line, the second heating line, and the compensation heating line; a is the first temperature coefficient, and b is the second temperature coefficient.

[0107] Adjust the current temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire to the compensation temperature value.

[0108] Optionally, a reference palladium sensor unit is provided in an insulated and enclosed manner at a symmetrical position to the palladium sensor unit in the gas flow pipeline.

[0109] Accordingly, after acquiring the resistance change value of the palladium sensor unit, the control unit is further configured to perform:

[0110] Determine the reference resistance value of the reference palladium sensor unit;

[0111] The resistance change value is obtained by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

[0112] Optionally, when the control unit acquires the resistance change value of the palladium sensor unit, it specifically performs the following:

[0113] The control unit determines a preset function representing the change in resistance and the change in hydrogen concentration.

[0114] The hydrogen concentration value is obtained by substituting the resistance change value into the change function.

[0115] The hydrogen concentration detection device provided in this embodiment of the invention can execute the hydrogen concentration detection method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0116] Example 5

[0117] Figure 6 This is a schematic diagram of a hydrogen concentration detection system provided in an embodiment of this application, as shown below. Figure 6 As shown, the system includes a hydrogen concentration detection device 610 and a gas flow pipeline 620; the hydrogen concentration detection device 610 is installed inside the gas flow pipeline 620.

[0118] The hydrogen concentration detection device is used to perform the hydrogen concentration detection method described in any of the above embodiments.

[0119] Optionally, the system further includes: a reference metal palladium sensor unit;

[0120] The hydrogen concentration detection device is used to determine the reference resistance value of the reference palladium sensor unit.

[0121] The resistance change value is obtained by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

[0122] Optionally, the heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire, wherein the first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the upper and lower surfaces of the palladium sensor unit, and the supplementary heating wire is disposed inside the palladium sensor unit.

[0123] Optionally, the system further includes: a heat insulation unit; the heat insulation unit is disposed on the inner wall and / or outer wall of the gas flow duct.

[0124] For the gas flow duct, ceramic pipes can be selected. Ceramic pipes are thin, heat-resistant, and corrosion-resistant, making them suitable for gas flow. Ceramic pipes can be ordinary cylindrical or spiral-shaped. The heating unit can be connected to the control unit via the outer wall of the ceramic pipe. The insulation unit is a layer of insulation material, which can be installed on the inner wall, outer wall, or both walls of the ceramic pipe to prevent heat from diffusing outwards.

[0125] This application embodiment improves upon the traditional hydrogen sensor based on a palladium electrode, making the measurement results of the new hydrogen concentration detection system more accurate. It establishes a constant temperature space, effectively eliminating the influence of ambient temperature on the sensor measurement results.

[0126] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0127] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for detecting hydrogen concentration, characterized in that, The method is executed by a hydrogen concentration detection device, which includes a palladium metal sensor unit, a heating unit, a flow rate detection unit, and a control unit. The palladium metal sensor unit, heating unit, and flow rate detection unit are communicatively connected to the control unit. The hydrogen concentration detection device is installed within a gas flow pipeline. The method includes: The flow rate detection unit acquires the current gas flow rate value in the gas flow pipe and sends the current gas flow rate value to the control unit. The control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate. The resistance change value of the palladium sensor unit is obtained through the control unit; The control unit determines the hydrogen concentration in the gas flow pipe based on the resistance change value. The heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire. The first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the first surface and the second surface of the palladium metal sensor unit. The first surface is the surface of the palladium metal sensor unit away from the wall of the gas flow pipe, and the second surface is the surface of the palladium metal sensor unit close to the wall of the gas flow pipe. The supplementary heating wire is disposed inside the palladium metal sensor unit. Accordingly, the control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate value, including: The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value. The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value. The palladium sensor unit is heated by the first heating wire, the second heating wire, and the supplemental heating wire.

2. The method according to claim 1, characterized in that, In the gas flow pipeline, a reference palladium sensor unit is provided in an insulated and sealed manner at a position symmetrical to the palladium sensor unit. Accordingly, after obtaining the resistance change value of the palladium sensor unit through the control unit, the method further includes: Determine the reference resistance value of the reference palladium sensor unit; The resistance change value is updated by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

3. The method according to claim 1, characterized in that, The control unit determines the hydrogen concentration in the gas flow pipeline based on the resistance change value, including: The control unit determines a preset function representing the change in resistance and the change in hydrogen concentration. The hydrogen concentration value is obtained by substituting the resistance change value into the change function.

4. A hydrogen concentration detection device, characterized in that, include: The system includes a control unit, a palladium sensor unit, a heating unit, and a flow rate detection unit; the palladium sensor unit, the heating unit, and the flow rate detection unit are disposed within a gas flow pipeline, and the control unit is communicatively connected to the palladium sensor unit, the heating unit, and the flow rate detection unit. The flow rate detection unit is used to acquire the current gas flow rate value in the gas flow pipe and send the current gas flow rate value to the control unit; The control unit is configured to control the heating unit to heat the palladium sensor unit according to the current gas flow rate; acquire the resistance change value of the palladium sensor unit; and determine the hydrogen concentration value in the gas flow pipeline based on the resistance change value. The heating unit includes a first heating wire, a second heating wire, and a supplementary heating wire. The first heating wire and the second heating wire are respectively arranged in a sawtooth shape on the first surface and the second surface of the palladium metal sensor unit. The first surface is the surface of the palladium metal sensor unit away from the wall of the gas flow pipe, and the second surface is the surface of the palladium metal sensor unit close to the wall of the gas flow pipe. The supplementary heating wire is disposed inside the palladium metal sensor unit. Accordingly, when the control unit controls the heating unit to heat the palladium sensor unit based on the current gas flow rate value, it specifically performs the following: The control unit determines the target control current value corresponding to the current gas flow rate value based on the preset correspondence between the gas flow rate value and the control current value. The control unit adjusts the temperature values ​​of the first heating wire, the second heating wire, and the supplementary heating wire respectively according to the target control current value. The palladium sensor unit is heated by the first heating wire, the second heating wire, and the supplemental heating wire.

5. A hydrogen concentration detection system, characterized in that, It includes a hydrogen concentration detection device and a gas flow pipeline; the hydrogen concentration detection device is installed inside the gas flow pipeline; The hydrogen concentration detection device is used to perform the hydrogen concentration detection method according to any one of claims 1-3.

6. The system according to claim 5, characterized in that, The system further includes: a reference metal palladium sensor unit; The hydrogen concentration detection device is used to determine the reference resistance value of the reference palladium sensor unit. The resistance change value is updated by subtracting the reference resistance value from the actual resistance change value of the palladium sensor unit.

7. The system according to claim 5, characterized in that, The system further includes: a heat insulation unit; The heat insulation unit is disposed on the inner wall and / or outer wall of the gas flow duct.

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