Gas meter and gas leakage detection method

Abstract

The invention provides a gas meter which is assembled on a gas pipeline and comprises a pressure detection module, a component detection module and a control module. The pressure detection module is used for detecting the pressure in the gas pipeline to obtain a pressure value; the component detection module is used for detecting the gas concentration in the gas pipeline to obtain a concentration characterization value capable of characterizing the gas concentration; the control module is in communication connection with the pressure detection module and the component detection module, and receives a pressure value sent by the pressure detection module and a concentration characterization value sent by the component detection module; the control module is further used for sending an alarm signal, and the alarm signal is generated when the concentration characterization value exceeds a preset range and the pressure value is lower than a preset pressure threshold value. According to the gas meter provided by the invention, the gas leakage condition and the gas exchange condition can be distinguished, so that the preset range of the concentration characterization value can be narrowed, whether air is mixed into the gas pipeline or not can be detected in time, and the gas use safety is improved.

Description

Technical Field

[0001] The present application relates to the field of gas monitoring technology, and in particular to a gas meter and a gas leak detection method. Background Art

[0002] When air is mixed into the gas pipeline, it may cause explosion and pose a safety hazard.

[0003] Related technologies are unable to distinguish between different gas components and air-fuel mixtures. To prevent false alarms, the alarm must be activated only after air is detected. If the leakage is small, resulting in only partial air mixing into the meter and incomplete replacement with air, the gas meter will not detect the anomaly. In other words, existing solutions require that the change in the composition of the pipe reaches a certain limit before detection. The limit is usually set to nearly complete conversion to air. This is because it is necessary to distinguish between ventilation and leakage. If the limit is increased, ventilation and leakage may be confused, resulting in false alarms.

[0004] Therefore, the detection means for detecting whether air is mixed in the gas pipeline in the related art is not timely enough, and there are safety hazards. Summary of the Invention

[0005] The purpose of this application is to provide a technical solution to solve the problem of insufficient timeliness of air-fuel mixture detection in gas pipelines existing in the related art.

[0006] Based on the above problems, the present application provides a gas meter, which is assembled on a gas pipeline and includes: a pressure detection module, a component detection module and a control module.

[0007] The pressure detection module is used to detect the pressure in the gas pipeline and obtain the pressure value;

[0008] Used to detect the gas concentration in the gas pipeline and obtain a concentration characterization value that can characterize the gas concentration;

[0009] The control module is respectively connected to the pressure detection module and the component detection module for communication, and receives the pressure value sent by the pressure detection module and the concentration representation value sent by the component detection module;

[0010] The control module is further configured to send an alarm signal, which is generated when the concentration representation value exceeds a preset range and the pressure value is lower than a preset pressure threshold.

[0011] Furthermore, the component detection module includes an ultrasonic transceiver unit, which is used to detect the propagation speed of the ultrasonic wave. The propagation medium of the ultrasonic wave is the mixed gas in the gas pipeline, and the concentration representation value is the sound speed of the ultrasonic wave.

[0012] The control module is used to set a sound velocity threshold, wherein the difference between the sound velocity threshold and the second sound velocity is greater than or equal to 0.3 times the difference between the first sound velocity and the second sound velocity, and the difference between the sound velocity threshold and the second sound velocity is less than or equal to 0.9 times the difference between the first sound velocity and the second sound velocity, wherein the first sound velocity is a theoretical propagation velocity of ultrasonic waves in a mixed gas, and the second sound velocity is a propagation velocity of ultrasonic waves in air;

[0013] The control module is also used to send an alarm signal, which is generated when the ultrasonic transceiver unit detects that the ultrasonic sound velocity value is lower than the sound velocity threshold, and the pressure detection module detects that the pressure value is lower than the preset pressure threshold.

[0014] Furthermore, the gas meter also includes a communication module, which is connected to the remote monitoring platform to query the temperature of the area where the gas meter is located;

[0015] The gas meter also queries the theoretical propagation speed of ultrasonic waves in the mixed gas at the temperature to obtain the first sound speed;

[0016] The gas meter also queries the propagation speed of ultrasonic waves in air at the temperature to obtain the second sound speed;

[0017] The control module is used to set a sound speed threshold according to the first sound speed and the second sound speed.

[0018] Furthermore, the component detection module includes a thermal conductivity sensing unit, which is used to detect the thermal conductivity of the mixed gas in the gas pipeline;

[0019] The control module is provided with a thermal conductivity threshold value, wherein the difference between the thermal conductivity threshold value and the first thermal conductivity value is greater than or equal to 0.3 times the difference between the second thermal conductivity value and the first thermal conductivity value, and the difference between the thermal conductivity threshold value and the first thermal conductivity value is less than or equal to 0.9 times the difference between the second thermal conductivity value and the first thermal conductivity value, wherein the first thermal conductivity value is a theoretical thermal conductivity value of the mixed gas, and the second thermal conductivity value is a thermal conductivity value of air;

[0020] The control module is used to send an alarm signal, which is generated when the thermal conductivity of the mixed gas detected by the thermal conductivity sensing unit is higher than the thermal conductivity threshold, and the pressure detection module detects that the pressure value is lower than the preset pressure threshold.

[0021] Furthermore, the gas meter also includes a communication module, which is connected to the remote monitoring platform to query the temperature of the area where the gas meter is located;

[0022] The gas meter also queries a theoretical thermal conductivity value of the mixed gas at the temperature to obtain a first thermal conductivity value;

[0023] The gas meter also queries the thermal conductivity value of the air at the temperature to obtain a second thermal conductivity value;

[0024] The control module is configured to set a sound velocity threshold value according to the first thermal conductivity value and the second thermal conductivity value.

[0025] Furthermore, the gas meter also includes a communication module, which is connected to the remote monitoring platform to query the temperature of the area where the gas meter is located;

[0026] The control module is also used to set the pressure threshold. The control module adjusts the pressure threshold through self-learning based on the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

[0027] Furthermore, the gas meter is also connected to the gas-consuming device through the communication module, and the gas meter receives temperature information from the gas-consuming device;

[0028] Gas meters are also used to monitor flow conditions in gas pipelines;

[0029] The control module determines whether the gas-consuming equipment is using gas based on the temperature information of the gas-consuming equipment. If it is determined that the gas-consuming equipment is not using gas and the gas meter still detects flow in the gas pipeline, it is determined that there is a gas leak.

[0030] Furthermore, when the control module determines that the gas-consuming device is consuming gas, if the concentration characterization value exceeds a preset range, the control module is configured to send an alarm signal.

[0031] The present application also provides a gas leak detection method, the method comprising:

[0032] Detect the pressure in the gas pipeline and obtain the pressure value;

[0033] Detecting the gas concentration in the gas pipeline to obtain a concentration characterization value that can characterize the gas concentration;

[0034] When the concentration characteristic value exceeds the preset range and the pressure value is lower than the preset pressure threshold, an alarm signal is generated.

[0035] Furthermore, the method further comprises:

[0036] Check the temperature of the area where the gas meter is located;

[0037] The pressure threshold is adjusted through self-learning based on the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

[0038] According to the above description, the gas meter provided in this application can distinguish between gas leakage conditions and ventilation conditions. Therefore, the preset range of the concentration characterization value can be narrowed, so that whether air is mixed in the gas pipeline can be detected in time, thereby improving gas safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of the gas flow provided in the first embodiment of the present application;

[0040] Figure 2 A schematic diagram of the gas flow provided in the second embodiment of the present application;

[0041] Figure 3 This is a schematic diagram of the gas flow provided in the third embodiment of the present application;

[0042] Figure 4 A schematic diagram showing the connection between the gas meter and gas-consuming equipment provided in the embodiment of the present application;

[0043] Figure 5 This is a flow chart of the gas leak detection method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The present application will be described in detail below in conjunction with the specific embodiments shown in the accompanying drawings, but these embodiments do not limit the present application. Structural, methodological, or functional changes made by ordinary technicians in this field based on these embodiments are included in the scope of protection of the present application.

[0045] For the sake of convenience, in the embodiments of the present application, the gas in the gas pipeline is referred to as mixed gas.

[0046] like Figure 1 As shown, an embodiment of the present application provides a gas meter 100 , which is assembled on a gas pipeline. The gas meter 100 includes a pressure detection module 11 , a component detection module 12 and a control module 13 .

[0047] The pressure detection module 11 is used to detect the pressure in the gas pipeline and obtain a pressure value, and the component detection module 12 is used to detect the gas concentration in the gas pipeline and obtain a concentration characterization value that can characterize the gas concentration.

[0048] The control module 13 is in communication with the pressure detection module 11 and the component detection module 12, respectively, and receives the pressure value sent by the pressure detection module 11 and the concentration representative value sent by the component detection module 12. The control module 13 is also used to send an alarm signal. The alarm signal is generated when the concentration representative value exceeds a preset range and the pressure value falls below a preset pressure threshold.

[0049] Specifically, when a gas pipeline leaks, the gas concentration in the pipeline will decrease. When the gas concentration drops beyond a limit, an alarm is required to alert users of a gas leak. The drop in gas concentration can be reflected in the concentration representation value. Therefore, a preset range can be set according to the drop limit of the gas concentration. When the concentration representation value exceeds the preset range, an alarm can be issued.

[0050] In related technologies, concentration indicative values ​​can be the velocity of ultrasound in a gas mixture or the thermal conductivity of the gas mixture. However, in practical applications, gas supply sources may change. Depending on the gas source, the composition of the gas mixture within the gas pipeline may vary, resulting in different measured concentration indicative values. The concentration indicative value alone cannot distinguish between ventilation and leakage conditions in the gas pipeline. To avoid misjudgment, the preset range of concentration indicative values ​​is typically based on the air measurement values ​​of the component detection module 12.

[0051] For example, if component detection module 12 uses ultrasonic detection technology, component detection module 12 determines that the propagation speed of ultrasonic waves in air is approximately 340 m / s. Related technologies often use this as a benchmark, setting a sound speed threshold close to 340 m / s, for example, 350 m / s, to avoid misjudgments. However, while this approach can avoid misjudgments, it clearly does not provide timely detection of air contamination in gas pipelines, posing a safety hazard.

[0052] In this regard, the present application combines the concentration characterization value with the pressure value in the gas pipeline, so that the ventilation condition of the gas pipeline can be distinguished from the leakage condition.

[0053] Specifically, the gas meter 100 provided in this application can detect the pressure value and gas concentration within the gas pipeline. If a pressure change is detected within the gas pipeline, but the concentration representative value does not change significantly, the pressure change can be considered to be a fluctuation in the pipeline network. If no significant pressure change is detected within the gas pipeline, for example, the pressure value remains above a preset pressure threshold, while the concentration representative value exceeds a preset range, the change in the concentration representative value can be considered to be caused by switching the gas supply source, rather than a pipeline leak. If a significant change is detected in both the pressure value and the concentration representative value, for example, the concentration representative value exceeds a preset range and the pressure value is below a preset pressure threshold, it can be confirmed that the pipeline is damaged and a gas leak has caused a pressure drop within the gas pipeline. At the same time, air has also entered the pipeline, requiring an alarm for timely processing.

[0054] According to the above description, the gas meter 100 provided in this application can distinguish between gas leakage conditions and ventilation conditions. Therefore, the preset range of the concentration characterization value can be narrowed, so that whether air is mixed in the gas pipeline can be detected in time, thereby improving gas safety.

[0055] like Figure 2 As shown, as an optional implementation, in the gas meter 100 provided in the embodiment of the present application, the component detection module 12 includes an ultrasonic transceiver unit 121, which is used to detect the propagation velocity of the ultrasonic wave. The propagation medium of the ultrasonic wave is the mixed gas in the gas pipeline, and the concentration representation value is the sound velocity of the ultrasonic wave.

[0056] The control module 13 is used to set a sound speed threshold, where the difference between the sound speed threshold and the second sound speed is greater than or equal to 0.3 times the difference between the first sound speed and the second sound speed, and the difference between the sound speed threshold and the second sound speed is less than or equal to 0.9 times the difference between the first sound speed and the second sound speed, where the first sound speed is the theoretical propagation speed of ultrasonic waves in a mixed gas, and the second sound speed is the propagation speed of ultrasonic waves in air.

[0057] The control module 13 is also used to send an alarm signal. The alarm signal is generated when the ultrasonic transceiver unit 121 detects that the ultrasonic sound velocity value is lower than the sound velocity threshold, and the pressure detection module 11 detects that the pressure value is lower than the preset pressure threshold.

[0058] Specifically, this application defines the theoretical propagation velocity of ultrasound in a gas mixture as the first sound velocity. The theoretical propagation velocity refers to the speed of ultrasound when propagating through the gas mixture in a gas pipeline, assuming no gas pipeline leaks. The propagation velocity of ultrasound in gas is affected by factors such as pressure and temperature. For ease of explanation, the theoretical propagation velocity of ultrasound in a gas mixture is 450 m / s in the examples of this application.

[0059] This application also defines the second speed of sound as the propagation speed of ultrasound in air. For ease of explanation, in the embodiments of this application, 340 m / s is used as the second speed of sound. It should be noted that the first speed of sound and the second speed of sound need to be set according to actual conditions. For ease of explanation only, 450 m / s is used as the first speed of sound and 340 m / s is used as the second speed of sound.

[0060] In the embodiment of the present application, the control module 13 is used to set a sound speed threshold value, and the difference between the sound speed threshold value and the second sound speed is greater than or equal to 0.3 times the difference between the first sound speed and the second sound speed, and the difference between the sound speed threshold value and the second sound speed is less than or equal to 0.9 times the difference between the first sound speed and the second sound speed. According to the difference between the first sound speed and the second sound speed being 110m / s, it can be seen that the setting range of the sound speed threshold value of the present application is greater than or equal to 373m / s and less than or equal to 439m / s. In the embodiment of the present application, the sound speed threshold value can be taken as 400m / s.

[0061] According to the above configuration, when control module 13 detects that the ultrasonic propagation velocity in the gas mixture is less than 400 m / s and the pressure in the gas pipeline is less than a preset pressure threshold, a gas pipeline leak is detected. By combining ultrasonic velocity detection with pipeline pressure detection, there is no need to wait for the ultrasonic propagation velocity in the gas mixture to drop to approximately 340 m / s. This ensures accurate leak detection while providing an early alarm, enhancing gas safety.

[0062] As an optional implementation, the gas meter 100 further includes a communication module 14 , which is in communication with the remote monitoring platform 200 to query the temperature of the area where the gas meter 100 is located;

[0063] The gas meter 100 also queries the theoretical propagation speed of ultrasound in the mixed gas at the temperature of the area where the gas meter 100 is located to obtain a first sound speed; the gas meter 100 also queries the propagation speed of ultrasound in the air at the temperature of the area where the gas meter 100 is located to obtain a second sound speed; the control module 13 is used to set the sound speed threshold according to the first sound speed and the second sound speed.

[0064] According to the above description, the gas meter 100 provided in this application can adjust the sound velocity threshold according to the local temperature conditions, thereby avoiding the gas meter 100 from mistakenly judging the change in ultrasonic sound velocity caused by temperature fluctuations as a change in gas composition, thereby improving the detection accuracy of the gas meter 100.

[0065] As an optional implementation, the sound velocity threshold can also be set with reference to a preset pressure threshold. Specifically, based on a large amount of experimental data, the relationship between pressure changes and sound velocity changes when a gas pipeline leak occurs can be obtained. This allows the corresponding ultrasonic sound velocity range to be determined when the pressure in the gas pipeline equals the preset pressure threshold. The sound velocity threshold can then be set with reference to this ultrasonic sound velocity range. In this way, the sound velocity threshold can be set more reasonably.

[0066] like Figure 3 As shown, as another optional implementation, the component detection module 12 includes a thermal conductivity sensing unit 122, which is used to detect the thermal conductivity of the mixed gas in the gas pipeline;

[0067] The control module 13 is provided with a thermal conductivity threshold value, wherein the difference between the thermal conductivity threshold value and the first thermal conductivity value is greater than or equal to 0.3 times the difference between the second thermal conductivity value and the first thermal conductivity value, and the difference between the thermal conductivity threshold value and the first thermal conductivity value is less than or equal to 0.9 times the difference between the second thermal conductivity value and the first thermal conductivity value, wherein the first thermal conductivity value is a theoretical thermal conductivity value of the mixed gas, and the second thermal conductivity value is a thermal conductivity value of air;

[0068] The control module 13 is used to send an alarm signal. The alarm signal is generated when the thermal conductivity of the mixed gas detected by the thermal conductivity sensing unit 122 is higher than the thermal conductivity threshold, and the pressure detection module 11 detects a pressure value lower than a preset pressure threshold.

[0069] Specifically, if a gas pipeline leaks, air will enter the pipeline, causing the thermal conductivity of the mixed gas in the pipeline to increase. If the leak is determined solely based on the thermal conductivity, the alarm will generally not be triggered until the thermal conductivity rises close to that of air, thus eliminating the ventilation problem.

[0070] The present application combines the detection of the thermal conductivity value of the mixed gas with the detection of the gas pipeline pressure value, so that the thermal conductivity threshold value can be set higher than the thermal conductivity value of air, and the difference between the thermal conductivity threshold value and the first thermal conductivity value is greater than or equal to 0.3 times the difference between the second thermal conductivity value and the first thermal conductivity value, and the difference between the thermal conductivity threshold value and the first thermal conductivity value is less than or equal to 0.9 times the difference between the second thermal conductivity value and the first thermal conductivity value. This can ensure accuracy while ensuring early alarm and improve gas safety.

[0071] As an optional implementation, the gas meter 100 further includes a communication module 14 , which is connected to the remote monitoring platform 200 for communication to query the temperature of the area where the gas meter 100 is located.

[0072] The gas meter 100 also queries the theoretical thermal conductivity of the mixed gas at the temperature to obtain a first thermal conductivity value; the gas meter 100 also queries the thermal conductivity of the air at the temperature to obtain a second thermal conductivity value; the control module 13 is used to set the sound speed threshold according to the first thermal conductivity value and the second thermal conductivity value.

[0073] According to the above description, the gas meter 100 provided in the present application can adjust the thermal conductivity threshold according to the local temperature conditions, thereby preventing the gas meter 100 from mistakenly judging the change in the thermal conductivity value of the mixed gas caused by temperature fluctuations as a change in the gas composition, thereby improving the detection accuracy of the gas meter 100.

[0074] As an optional implementation, the pressure threshold may be set based on analysis of a large amount of experimental data and obtained using empirical data.

[0075] As another optional implementation, the gas meter 100 can communicate with the remote monitoring platform 200 via the communication module 14 to query the temperature of the area where the gas meter 100 is located. The control module 13 is also used to set a pressure threshold. The control module 13 adjusts the pressure threshold through self-learning based on the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

[0076] According to the above description, the gas meter 100 provided in the embodiment of the present application can autonomously adjust the pressure threshold according to the temperature of the area through machine learning, thereby avoiding false alarms caused by pressure changes in the gas pipeline caused by temperature.

[0077] like Figure 4As shown, as an optional implementation, the gas meter 100 can also be connected to the gas-consuming device 300 through the communication module 14, and the gas meter 100 receives temperature information of the gas-consuming device 300. The gas meter 100 can be used to monitor the flow condition in the gas pipeline.

[0078] The control module 13 determines whether the gas-consuming device 300 is using gas based on the temperature information of the gas-consuming device 300. If it is determined that the gas-consuming device 300 is not using gas and the gas meter 100 also detects flow in the gas pipeline, it is determined that there is a gas leak.

[0079] Specifically, gas-consuming device 300 may be a gas stove equipped with a temperature monitoring device to monitor the stove's temperature. When the stove is in use, the temperature monitoring device can detect a significant temperature rise. Control module 13 is in communication with gas-consuming device 300 and can determine whether gas is being used based on the temperature of gas-consuming device 300. If gas-consuming device 300 is not being used, but gas meter 100 detects gas flow in the gas pipeline, a gas leak is considered to have occurred.

[0080] According to the above description, this application installs temperature sensors on all gas-using equipment 300 and realizes wireless networking of the gas-using equipment 300 and the gas meter 100. When the gas meter 100 detects flow but there is no obvious temperature increase in all gas-using equipment 300, it can be determined that there is a gas leak.

[0081] As an optional implementation, when the control module 13 determines that the gas-consuming device 300 is consuming gas, if it is detected that the concentration characterization value exceeds a preset range, the control module 13 sends an alarm signal.

[0082] Specifically, the user's use of gas will inevitably cause the pressure in the gas pipeline to drop. At this time, whether the pressure value drops below the pressure threshold is no longer used as the criterion for judging whether there is a leak. As long as the concentration characterization value is detected to exceed the preset range, an alarm needs to be issued and the gas-using equipment 300 needs to be shut down to avoid accidents caused by open flames.

[0083] like Figure 5 As shown, the present application also provides a gas leak detection method, comprising the following steps:

[0084] S1. Detect the pressure in the gas pipeline and obtain the pressure value;

[0085] S2. Detecting the gas concentration in the gas pipeline to obtain a concentration characterization value capable of characterizing the gas concentration;

[0086] S3. When the concentration characteristic value exceeds the preset range and the pressure value is lower than the preset pressure threshold, an alarm signal is generated.

[0087] The method provided in this application also includes:

[0088] S4. Querying the temperature of the area where the gas meter 100 is located;

[0089] S5. Adjust the pressure threshold through self-learning based on the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

[0090] According to the above description, the gas leak detection method provided in this application can distinguish between gas leakage conditions and ventilation conditions, thereby narrowing the preset range of concentration characterization values, so that whether air is mixed in the gas pipeline can be detected in time, thereby improving gas safety.

[0091] The above disclosure is only a preferred embodiment of the present application, but it is not intended to limit the scope of rights of the present application. A person skilled in the art can understand that without departing from the spirit and scope of the present application and the appended claims, changes, modifications, substitutions, combinations, and simplifications should all be equivalent replacement methods and still fall within the scope of the invention.

Claims

1. A gas meter, the gas meter being mounted on a gas pipeline, comprising: A pressure detection module, the pressure detection module is used to detect the pressure in the gas pipeline and obtain a pressure value; A component detection module, used to detect the gas concentration in the gas pipeline and obtain a concentration characterization value capable of characterizing the gas concentration; A control module, wherein the control module is respectively connected to the pressure detection module and the component detection module for communication, and receives the pressure value sent by the pressure detection module and the concentration characterization value sent by the component detection module; The control module is further configured to send an alarm signal, wherein the alarm signal is generated when the concentration characterization value exceeds a preset range and the pressure value is lower than a preset pressure threshold.

2. The gas meter according to claim 1, characterized in that: The component detection module includes an ultrasonic transceiver unit, which is used to detect the propagation speed of the ultrasonic wave. The propagation medium of the ultrasonic wave is the mixed gas in the gas pipeline, and the concentration characterization value is the sound speed of the ultrasonic wave. The control module is used to set a sound velocity threshold, the difference between the sound velocity threshold and the second sound velocity is greater than or equal to 0.3 times the difference between the first sound velocity and the second sound velocity, and the difference between the sound velocity threshold and the second sound velocity is less than or equal to 0.9 times the difference between the first sound velocity and the second sound velocity, wherein the first sound velocity is a theoretical propagation velocity of an ultrasonic wave in the mixed gas, and the second sound velocity is a propagation velocity of an ultrasonic wave in air; The control module is also used to send the alarm signal, which is generated when the ultrasonic transceiver unit detects that the ultrasonic sound velocity value is lower than the sound velocity threshold, and the pressure detection module detects that the pressure value is lower than the preset pressure threshold.

3. The gas meter according to claim 2, characterized in that: The gas meter further comprises a communication module, which is connected to the remote monitoring platform for querying the temperature of the area where the gas meter is located; The gas meter further queries the theoretical propagation speed of the ultrasonic wave in the mixed gas at the temperature to obtain the first sound speed; The gas meter further queries the propagation speed of the ultrasonic wave in the air at the temperature to obtain the second sound speed; The control module is used to set the sound speed threshold according to the first sound speed and the second sound speed.

4. The gas meter according to claim 1, characterized in that: The component detection module includes a thermal conductivity sensing unit, and the thermal conductivity sensing unit is used to detect the thermal conductivity of the mixed gas in the gas pipeline; The control module is provided with a thermal conductivity threshold, the difference between the thermal conductivity threshold and a first thermal conductivity value is greater than or equal to 0.3 times the difference between a second thermal conductivity value and the first thermal conductivity value, and the difference between the thermal conductivity threshold and the first thermal conductivity value is less than or equal to 0.9 times the difference between the second thermal conductivity value and the first thermal conductivity value, wherein the first thermal conductivity value is a theoretical thermal conductivity value of the mixed gas, and the second thermal conductivity value is a thermal conductivity value of air; The control module is used to send the alarm signal, and the alarm signal is generated when the thermal conductivity of the mixed gas detected by the thermal conductivity sensing unit is higher than the thermal conductivity threshold, and the pressure detection module detects that the pressure value is lower than the preset pressure threshold.

5. The gas meter according to claim 4, characterized in that: The gas meter further comprises a communication module, which is connected to the remote monitoring platform for querying the temperature of the area where the gas meter is located; The gas meter further queries the theoretical thermal conductivity value of the mixed gas at the temperature to obtain the first thermal conductivity value; The gas meter further queries the thermal conductivity of the air at the temperature to obtain the second thermal conductivity; The control module is used to set the sound speed threshold according to the first thermal conductivity value and the second thermal conductivity value.

6. The gas meter according to claim 1, characterized in that: The gas meter further comprises a communication module, which is connected to the remote monitoring platform for querying the temperature of the area where the gas meter is located; The control module is also used to set the pressure threshold. The control module adjusts the pressure threshold by self-learning according to the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

7. The gas meter according to claim 6, characterized in that: The gas meter is also connected to the gas-consuming device through the communication module, and the gas meter receives the temperature information of the gas-consuming device; The gas meter is also used to monitor the flow condition in the gas pipeline; The control module determines whether the gas-consuming device is using gas based on the temperature information of the gas-consuming device. If it is determined that the gas-consuming device is not using gas and the gas meter also detects flow in the gas pipeline, it is determined that there is a gas leak.

8. The gas meter according to claim 7, characterized in that: When the control module determines that the gas-consuming device is consuming gas, if the concentration characterization value exceeds the preset range, the control module is configured to send an alarm signal.

9. A gas leak detection method, characterized in that: The method comprises: Detect the pressure in the gas pipeline and obtain the pressure value; Detecting the gas concentration in the gas pipeline to obtain a concentration characterization value capable of characterizing the gas concentration; When the concentration characterization value exceeds a preset range and the pressure value is lower than a preset pressure threshold, an alarm signal is generated.

10. The gas leak detection method according to claim 9, characterized in that: The method further comprises: Querying the temperature of the area where the gas meter is located; The pressure threshold is adjusted by self-learning according to the pressure data when there is no flow in the gas pipeline and the temperature data of the area.

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