Combustible gas concentration detection method

Abstract

The present invention discloses a method for detecting the concentration of combustible gas. The method for detecting the concentration of combustible gas comprises: obtaining the current reaction temperature inside the combustible gas sensor; determining the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity; determining the current combustible gas concentration according to the current response signal output by the combustible gas sensor and the target detection sensitivity. The technical solution of the embodiment of the present invention can improve the detection accuracy of the combustible gas concentration.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection, and in particular to a method for detecting the concentration of combustible gas. Background Art

[0002] When detecting the concentration of combustible gas, the combustible gas sensor usually directly calculates the gas concentration according to the response signal (such as voltage or current) output by the combustible gas sensor, resulting in low detection accuracy of the gas concentration. Summary of the invention

[0003] The present invention provides a combustible gas concentration detection method to improve the detection accuracy of the combustible gas concentration.

[0004] The present invention provides a method for detecting combustible gas concentration, comprising:

[0005] Get the current reaction temperature inside the combustible gas sensor;

[0006] Determining the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity;

[0007] The current combustible gas concentration is determined according to the current response signal output by the combustible gas sensor and the target detection sensitivity.

[0008] Optionally, the combustible gas sensor comprises: a heating circuit and a detection circuit; the heating circuit comprises a heating resistor, and the detection circuit comprises a detection element composed of a gas-sensitive material; the heating resistor and the detection element are arranged on the same substrate;

[0009] The obtaining of the current reaction temperature inside the combustible gas sensor includes:

[0010] The current temperature of the heating resistor is obtained as the current reaction temperature.

[0011] Optionally, a heating voltage is connected to both ends of the heating circuit; the heating circuit further comprises: a current detection component for detecting the current flowing through the heating resistor;

[0012] The obtaining of the current temperature of the heating resistor comprises:

[0013] detecting a current flowing through the heating resistor;

[0014] Determining a current resistance value of the heating resistor according to the current current and the heating voltage;

[0015] The current temperature is determined according to the corresponding relationship between the resistance value of the heating resistor and the temperature and the current resistance value of the heating resistor.

[0016] Optionally, the combustible gas concentration detection method further includes: during the combustible gas concentration detection process, controlling the heating voltage to remain constant.

[0017] Optionally, while obtaining the current reaction temperature inside the combustible gas sensor, it also includes:

[0018] Obtaining the current ambient temperature of the environment where the combustible gas sensor is located;

[0019] Accordingly, determining the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity includes:

[0020] According to the correspondence between the reaction temperature and the detection sensitivity at the current ambient temperature, the target detection sensitivity of the combustible gas sensor at the current reaction temperature is determined; wherein the correspondence between the reaction temperature and the detection sensitivity is different at different ambient temperatures.

[0021] Optionally, the process of establishing the corresponding relationship between the reaction temperature and the detection sensitivity at any ambient temperature includes:

[0022] At the ambient temperature, at each of a plurality of different reaction temperatures, the detection sensitivity of the combustible gas sensor at the reaction temperature is determined according to the response signals respectively outputted by the combustible gas sensor at a plurality of different combustible gas concentrations;

[0023] According to the multiple different reaction temperatures and the detection sensitivity of the combustible gas at the multiple different reaction temperatures, a corresponding relationship between the reaction temperature and the detection sensitivity at the ambient temperature is obtained.

[0024] Optionally, determining the current combustible gas concentration according to the current response signal output by the combustible gas sensor and the target detection sensitivity includes:

[0025] Calculating a difference between the current response signal and an initial response signal of the combustible gas sensor in the absence of combustible gas as a current response signal variation;

[0026] The current combustible gas concentration is determined according to the current response signal change amount and the target detection sensitivity.

[0027] Optionally, the combustible gas sensor includes: a load resistor and a detection element made of a gas-sensitive material; the detection element and the load resistor are connected in series to form a detection circuit, and a detection voltage is applied across the detection circuit; the voltage across the load resistor serves as a response signal of the combustible gas sensor.

[0028] Optionally, the combustible gas concentration detection method further includes: during the combustible gas concentration detection process, controlling the humidity of the gas entering the combustible gas sensor to remain within a preset humidity range.

[0029] Optionally, a desiccant or a gas filter is used to control the humidity of the gas entering the combustible gas sensor.

[0030] The technical solution of the embodiment of the present invention obtains the current reaction temperature inside the combustible gas sensor, and determines the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity. Furthermore, the current combustible gas concentration is determined according to the current response signal output by the combustible gas sensor and the target detection sensitivity. The embodiment of the present invention is equivalent to considering the influence of the reaction temperature on the response signal output by the combustible gas sensor. The target detection sensitivity can be understood as the corrected detection sensitivity obtained by considering the influence of the reaction temperature change. Compared with the scheme of calculating the combustible gas concentration with a fixed detection sensitivity, the error of the detection result can be effectively reduced, thereby improving the detection accuracy of the combustible gas concentration, and avoiding the problem of false alarm or missed alarm of the combustible gas sensor due to the influence of the reaction temperature, thereby enhancing safety.

[0031] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 A flow chart of a combustible gas concentration detection method provided according to an embodiment of the present invention;

[0034] Figure 2 A schematic diagram of the structure of a combustible gas sensor provided according to an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of a circuit structure of a combustible gas sensor provided according to an embodiment of the present invention;

[0036] Figure 4 The present invention is a flowchart of another combustible gas concentration detection method provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] 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.

[0038] 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 their variations 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 clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] Figure 1 A flow chart of a combustible gas concentration detection method according to an embodiment of the present invention is provided. Figure 1 , the combustible gas concentration detection methods include:

[0040] S101. Obtain the current reaction temperature inside the combustible gas sensor.

[0041] For ease of explanation, let's first combine Figure 2 and Figure 3 The structure and working process of the combustible gas sensor are briefly described. Figure 2 The combustible gas sensor includes a housing 100 and a detection component 101. The housing 100 is, for example, a metal cap with an air inlet hole on the top, and the detection component 101 is disposed inside the housing 100. The interior of the combustible gas sensor specifically refers to the internal space of the housing 100. The detection component 101 is, for example, a circuit board based on a ceramic substrate. Figure 3 Detailed circuit structure of the detection component 101 is shown. Figure 3 The detection component 101 of the combustible gas sensor includes: a heating circuit 10 and a detection circuit 11; the heating circuit 10 includes a heating resistor R H The detection circuit 11 includes a load resistor R2 connected in series and a detection element R composed of a gas-sensitive material. S .

[0042] A heating voltage VH is applied to both ends of the heating circuit 10, for example, a heating resistor R H A heating voltage VH is applied across the two ends, so that the heating resistor R H temperature rises, causing the detection element R S The temperature required to react with the combustible gas is reached. A detection voltage VCC is applied across the detection circuit 11, and the voltage V across the load resistor R2 is used as the response signal output by the combustible gas sensor. When combustible gas is introduced into the combustible gas sensor, the detection element R S The gas-sensitive material in the detector reacts with the combustible gas, causing the detection element R S The resistance value of the load resistor R2 changes, which causes the voltage V at both ends of the load resistor R2 to change. The reaction degree of different concentrations of combustible gas and gas-sensitive materials is different, resulting in the detection element R S The change in resistance value is different, so the change in voltage V across the load resistor R2 is also different. Accordingly, the response signal output by the combustible gas sensor can represent the concentration of the combustible gas. For example, the combustible gas sensor can be a semiconductor sensor.

[0043] Since the detection element R S When the gas-sensitive material in the combustible gas reacts with the combustible gas to release heat, the reaction temperature inside the combustible gas sensor will be different, and the characteristics of the gas-sensitive material at different reaction temperatures are different, which affects the response signal output by the combustible gas sensor. Therefore, it is necessary to detect the current reaction temperature of the combustible gas sensor. Specifically, the current reaction temperature inside the combustible gas sensor can be measured by a temperature detection device combined with a hardware circuit, and then the current reaction temperature can be obtained according to the output result of the temperature detection device.

[0044] S102: Determine the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity.

[0045] Among them, the detection sensitivity of the combustible gas sensor is: the proportional relationship between the change in the response signal of the combustible gas sensor and the change in the concentration of the combustible gas entering the combustible gas sensor, or the change in the response signal caused by the change in the unit concentration of the combustible gas. Here, illustratively, the detection sensitivity of the combustible gas sensor is the proportional relationship between the change in the voltage V across the load resistor R2 and the change in the concentration of the combustible gas. Exemplarily, when the reaction temperature is 420°C, the combustible gas concentration is 100ppm, and the response signal of the combustible gas sensor is 210mV; when the reaction temperature is 420°C, the combustible gas concentration is 200ppm, and the response signal of the combustible gas sensor is 290mV; at this time, ΔV=80mV, ΔP=100ppm, and the detection sensitivity corresponding to the reaction temperature of 420°C is 0.8mV / ppm.

[0046] Specifically, the reaction temperature and the detection sensitivity of the combustible gas sensor are in a one-to-one correspondence. That is, when the reaction temperature is different, the detection sensitivity is also different. When the current reaction temperature inside the combustible gas sensor is determined, the detection sensitivity obtained by substituting the current reaction temperature into the corresponding relationship between the reaction temperature and the detection sensitivity is the target detection sensitivity.

[0047] Exemplarily, the correspondence between the reaction temperature and the detection sensitivity can be stored in the form of a graph or a table. In the actual detection process, the target detection sensitivity can be obtained by looking up the graph. In the case where the current reaction temperature is not recorded in the graph or table, the detection sensitivity at the reaction temperature closest to the current reaction temperature can be selected as the target detection sensitivity, or fitting can be performed according to the data recorded in the graph or table to obtain the detection sensitivity at the current reaction temperature from the fitting data as the target detection sensitivity.

[0048] S103: Determine the current combustible gas concentration according to the current response signal output by the combustible gas sensor and the target detection sensitivity.

[0049] Specifically, the combustible gas concentration calculated by the correlation signal between the target detection sensitivity and the current response signal output by the combustible gas sensor is the current combustible gas concentration.

[0050] The technical solution of the embodiment of the present invention obtains the current reaction temperature inside the combustible gas sensor, and determines the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity. Furthermore, the current combustible gas concentration is determined according to the current response signal output by the combustible gas sensor and the target detection sensitivity. The embodiment of the present invention is equivalent to considering the influence of the reaction temperature on the response signal output by the combustible gas sensor. The target detection sensitivity can be understood as the corrected detection sensitivity obtained by considering the influence of the reaction temperature change. Compared with the scheme of using a fixed detection sensitivity to measure the combustible gas concentration, the error of the detection result can be effectively reduced, thereby improving the detection accuracy of the combustible gas concentration, and avoiding the problem of false alarm or missed alarm of the combustible gas sensor due to the influence of the reaction temperature, thereby enhancing safety.

[0051] On the basis of the above embodiment, optionally, there are multiple methods for obtaining the current reaction temperature inside the combustible gas sensor, which are described below respectively.

[0052] In one embodiment, optionally, an additional temperature sensor and its peripheral circuits can be integrated inside the combustible gas sensor, the current reaction temperature can be measured by the temperature sensor, and a voltage signal or digital signal proportional to the temperature can be directly output, and the current reaction temperature can be obtained based on the voltage signal or digital signal.

[0053] In another embodiment, optionally, the current reaction temperature can be determined based on the temperature of a heating resistor (such as a thermistor), which is described in detail below.

[0054] Specifically, the heating resistor R H With the detection element R S Set on the same substrate, so the heating resistor R H The temperature and detection element R S The temperature of the heating resistor R H The temperature of the detection element R is increased according to the heating voltage VH. S When combustible gas is introduced into the combustible gas sensor, the detection element R S The gas-sensitive material in the heating resistor R H The temperature of the heating resistor R H The temperature and detection element R S The temperature of the heating resistor R changes synchronously, and the two temperatures remain the same. H The temperature and detection element R S The temperature of the detection element R S The temperature is the reaction temperature.

[0055] Optionally, a heating resistor R H With the detection element R S It can be set on both the front and back sides of the substrate.

[0056] Then, obtaining the current reaction temperature inside the combustible gas sensor includes: obtaining the current temperature of the heating resistor as the current reaction temperature.

[0057] Continue to refer Figure 3 Optionally, the heating circuit 10 further includes: a current detection component for detecting the current flowing through the heating resistor R H There are many structures of current detection components and detection processes, several of which are described below, but they are not intended to limit the present invention.

[0058] See also Figure 3 In one embodiment, optionally, the current detection component may include a voltage divider resistor R1, and the resistance of the voltage divider resistor R1 is known. HThe heating circuit 10 is formed in series, and the heating voltage VH can be applied to the voltage divider resistor R1 and the heating resistor R H The two ends of the series structure. Accordingly, the current temperature of the heating resistor is obtained, including:

[0059] 1) Detect the current flowing through the heating resistor.

[0060] Specifically, the current voltage across the voltage-dividing resistor R1 is detected, and the current flowing through the heating resistor R is determined according to the current voltage and the resistance value of the voltage-dividing resistor R1. H The current of

[0061] 2) Determine the current resistance of the heating resistor based on the current current and the heating voltage.

[0062] Specifically, the heating resistor R is determined according to the current voltage across the voltage divider resistor R1 and the heating voltage VH. H The current voltage is based on the heating resistor R H The current voltage and current determine the heating resistance R H The current resistance value.

[0063] 3) Determine the current temperature based on the corresponding relationship between the resistance value of the heating resistor and the temperature and the current resistance value of the heating resistor.

[0064] Specifically, the heating resistor R H With a fixed temperature-resistance curve, when the heating resistor R H When the resistance value is known, the heating resistance R can be determined by the temperature-resistance curve H The current temperature. For example, the heating resistor R H It can be a metal resistor, whose resistance increases with increasing temperature.

[0065] In another optional embodiment of the present invention, the current detection component may include a current transformer, and the detection component of the current transformer may be sleeved on the heating resistor R H The power supply line is used to detect the current flowing through the heating resistor R H In this case, the heating voltage VH is directly applied to the heating resistor R H Correspondingly, the current temperature of the heating resistor is obtained, including: directly measuring the current flowing through the heating resistor R through the current transformer H The current of the heating resistor R H The current and heating voltage VH determine the heating resistance R H The current resistance value of the heating resistor R H The corresponding relationship between the resistance value and temperature and the heating resistance R H The current resistance value of the heating resistor R H The current temperature.

[0066] Based on the above embodiments, optionally, during the process of detecting the concentration of combustible gas, the detection voltage VCC of the combustible gas sensor remains constant. In this way, the voltage V at both ends of the load resistor R2 is only affected by the detection element R S The influence of resistance value change can avoid the influence of detection voltage VCC change on the detection result.

[0067] Optionally, during the detection of the combustible gas concentration, the heating voltage VH is controlled to be constant. H The current and resistance value present a unique corresponding relationship. This setting is helpful to improve the detection accuracy of the reaction temperature.

[0068] Alternatively, the detection voltage VCC and the heating voltage VH may be the same.

[0069] Figure 4 This is a flow chart of another combustible gas concentration detection method provided according to an embodiment of the present invention, referring to Figure 4 , the combustible gas concentration detection method may specifically include:

[0070] S201. Acquire the current reaction temperature inside the combustible gas sensor and the current ambient temperature of the environment where the combustible gas sensor is located.

[0071] That is, while obtaining the current reaction temperature inside the combustible gas sensor, the current ambient temperature of the environment where the combustible gas sensor is located is also obtained.

[0072] Since the ambient temperature affects the intake temperature of the combustible gas, when the ambient temperature is different, the intake temperature of the combustible gas is different, thereby affecting the response signal output by the combustible gas sensor. Based on this, it can be considered that the ambient temperature will also affect the response signal output by the combustible gas sensor. Then, the current reaction temperature inside the combustible gas sensor is obtained while the current ambient temperature is obtained to reduce the error of the response signal output by the combustible gas sensor. Specifically, the current ambient temperature of the environment where the combustible gas sensor is located can be measured by a temperature sensor. Among them, the temperature sensor can be set in the external environment of the combustible gas sensor.

[0073] S202. Determine the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity at the current ambient temperature; wherein the corresponding relationship between the reaction temperature and the detection sensitivity is different at different ambient temperatures.

[0074] Specifically, the correspondence between the reaction temperature and the detection sensitivity under different ambient temperatures can be stored separately; or, the correspondence between the reaction temperature and the detection sensitivity under different ambient temperatures can be integrated to form a correspondence between the ambient temperature, the reaction temperature and the detection sensitivity for storage.

[0075] When the reaction temperature of the combustible gas sensor under the current ambient temperature is determined, the corresponding detection sensitivity obtained by substituting the current reaction temperature into the corresponding relationship between the reaction temperature and the detection sensitivity under the current ambient temperature is the target detection sensitivity.

[0076] S203. Determine the current combustible gas concentration according to the current response signal output by the combustible gas sensor and the target detection sensitivity.

[0077] This embodiment provides a detection process for combustible gas concentration through S201-S203. The technical solution of the embodiment of the present invention, based on the consideration of the influence of the reaction temperature on the response signal output by the combustible gas sensor, further considers the influence of the ambient temperature on the reaction temperature and the response signal output by the combustible gas sensor. It can avoid the problem that the change in ambient temperature will cause the change in the oxygen partial pressure inside the combustible gas sensor, thereby affecting the accuracy of the output signal of the combustible gas sensor. The target detection sensitivity can be understood as the corrected detection sensitivity obtained by considering the influence of the change in ambient temperature and the change in reaction temperature. Compared with the solution of using a fixed detection sensitivity to measure the combustible gas concentration, it can effectively reduce the error of the detection result, thereby improving the detection accuracy of the combustible gas concentration. It can avoid the problem of false alarm or missed alarm caused by the influence of ambient temperature and reaction temperature of the combustible gas sensor, thereby enhancing safety.

[0078] On the basis of the above embodiments, optionally, determining the current combustible gas concentration according to the current response signal output by the combustible gas sensor and the target detection sensitivity includes:

[0079] 1) Calculate the difference between the current response signal and the initial response signal of the combustible gas sensor in the absence of combustible gas as the change in the current response signal.

[0080] The initial response signal can be specifically understood as the response signal of the combustible gas sensor when the concentration of the combustible gas is 0 at the current reaction temperature. Specifically, when the concentration of the combustible gas is 0, the response signal of the combustible gas sensor at the current reaction temperature is recorded as the initial response signal V0. When the concentration of the combustible gas increases, the response signal of the combustible gas sensor at the current reaction temperature is recorded as the current response signal V1. At this time, the change in the current response signal is V=V1-V0.

[0081] 2) Determine the current combustible gas concentration based on the current response signal change and target detection sensitivity.

[0082] Specifically, the current combustible gas concentration is calculated by dividing the current response signal change by the target detection sensitivity. For example, when the initial response signal is 10mV, the current response signal is 210mV, and the current reaction temperature at the current ambient temperature is 420°C, the current combustible gas concentration is (210mV-10mV) / (0.8mV / ppm)=250ppm.

[0083] Optionally, the process of establishing the corresponding relationship between the reaction temperature and the detection sensitivity at any ambient temperature includes:

[0084] 1) Under the ambient temperature, at each of a plurality of different reaction temperatures, the detection sensitivity of the combustible gas sensor at the reaction temperature is determined according to the response signals outputted by the combustible gas sensor at a plurality of different combustible gas concentrations.

[0085] Specifically, at the same ambient temperature, the reaction temperature of the combustible gas sensor can be fixed or adjusted by the heating device, and the combustible gas concentration can be accurately controlled by the mixed gas generator. Furthermore, at different reaction temperatures, for each combustible gas concentration, the response signal of the combustible gas sensor is recorded. Then, the detection sensitivity of the combustible gas sensor at the reaction temperature is determined.

[0086] 2) According to a plurality of different reaction temperatures and the detection sensitivity of the combustible gas at a plurality of different reaction temperatures, a corresponding relationship between the reaction temperature and the detection sensitivity at the ambient temperature is obtained.

[0087] Based on the above embodiments, optionally, during the detection of the combustible gas concentration, the humidity of the gas entering the combustible gas sensor is controlled to be maintained within a preset humidity range.

[0088] Since the factors affecting the response signal output by the combustible gas sensor include: the current reaction temperature of the combustible gas, the intake humidity of the combustible gas and the concentration of the combustible gas, by controlling the humidity of the gas entering the combustible gas sensor to be within the preset humidity range, the output response signal of the combustible gas sensor can be affected only by the two factors of the current reaction temperature of the combustible gas and the concentration of the combustible gas. This can further improve the detection accuracy of the combustible gas concentration.

[0089] The preset humidity range can be specifically understood as a humidity range set according to the working characteristics of the sensor, the application environment, the effect of humidity on the sensor performance, and industry standards. In this embodiment, for example, the preset humidity range can be to set the humidity to a fixed value (for example, the humidity value recorded in the sensor data manual) or to fix the humidity range to a smaller range by technical means.

[0090] Optionally, a desiccant or a gas filter device is used to control the humidity of the gas entering the combustible gas sensor.

[0091] Among them, the desiccant may include silica gel, molecular sieve, calcium chloride, etc., and the gas filtering device may include a membrane filter, a drying tube, etc., which is not specifically limited in this embodiment.

[0092] By setting a desiccant or gas filter to control the humidity of the gas entering the combustible gas sensor, water vapor in the combustible gas can be effectively removed and humidity fluctuations can be reduced, thereby ensuring that the combustible gas sensor can work stably in a dry environment and improving the accuracy of combustible gas concentration measurement. At the same time, by controlling humidity, corrosion, oxidation, and other chemical reactions inside the sensor caused by moisture can be avoided, thereby extending the service life of the combustible gas sensor and reducing maintenance and replacement costs.

[0093] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0094] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting combustible gas concentration, characterized in that: include: Get the current reaction temperature inside the combustible gas sensor; Determining the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity; The current combustible gas concentration is determined according to the current response signal output by the combustible gas sensor and the target detection sensitivity.

2. The combustible gas concentration detection method according to claim 1, characterized in that: The combustible gas sensor comprises: a heating circuit and a detection circuit; the heating circuit comprises a heating resistor, and the detection circuit comprises a detection element composed of a gas-sensitive material; the heating resistor and the detection element are arranged on the same substrate; The obtaining of the current reaction temperature inside the combustible gas sensor includes: The current temperature of the heating resistor is obtained as the current reaction temperature.

3. The combustible gas concentration detection method according to claim 2, characterized in that: The two ends of the heating circuit are connected to a heating voltage; the heating circuit further comprises: a current detection component for detecting the current flowing through the heating resistor; The obtaining of the current temperature of the heating resistor comprises: detecting a current flowing through the heating resistor; Determining a current resistance value of the heating resistor according to the current current and the heating voltage; The current temperature is determined according to the corresponding relationship between the resistance value of the heating resistor and the temperature and the current resistance value of the heating resistor.

4. The combustible gas concentration detection method according to claim 3, characterized in that: Also includes: During the detection of the combustible gas concentration, the heating voltage is controlled to remain constant.

5. The combustible gas concentration detection method according to claim 3, characterized in that: While obtaining the current reaction temperature inside the combustible gas sensor, it also includes: Obtaining the current ambient temperature of the environment where the combustible gas sensor is located; Accordingly, determining the target detection sensitivity of the combustible gas sensor at the current reaction temperature according to the corresponding relationship between the reaction temperature and the detection sensitivity includes: According to the correspondence between the reaction temperature and the detection sensitivity at the current ambient temperature, the target detection sensitivity of the combustible gas sensor at the current reaction temperature is determined; wherein the correspondence between the reaction temperature and the detection sensitivity is different at different ambient temperatures.

6. The combustible gas concentration detection method according to claim 5, characterized in that: The process of establishing the corresponding relationship between the reaction temperature and the detection sensitivity at any ambient temperature includes: At the ambient temperature, at each of a plurality of different reaction temperatures, the detection sensitivity of the combustible gas sensor at the reaction temperature is determined according to the response signals respectively outputted by the combustible gas sensor at a plurality of different combustible gas concentrations; According to the multiple different reaction temperatures and the detection sensitivity of the combustible gas at the multiple different reaction temperatures, a corresponding relationship between the reaction temperature and the detection sensitivity at the ambient temperature is obtained.

7. The combustible gas concentration detection method according to claim 1, characterized in that: Determining a current combustible gas concentration according to a current response signal output by the combustible gas sensor and the target detection sensitivity includes: Calculating a difference between the current response signal and an initial response signal of the combustible gas sensor in the absence of combustible gas as a current response signal variation; The current combustible gas concentration is determined according to the current response signal change amount and the target detection sensitivity.

8. The combustible gas concentration detection method according to any one of claims 1 to 7, characterized in that: The combustible gas sensor comprises: a load resistor and a detection element made of a gas-sensitive material; the detection element and the load resistor are connected in series to form a detection circuit, and a detection voltage is applied across the detection circuit; the voltage across the load resistor serves as a response signal of the combustible gas sensor.

9. The combustible gas concentration detection method according to any one of claims 1 to 7, characterized in that: Also includes: During the detection of the combustible gas concentration, the humidity of the gas entering the combustible gas sensor is controlled to be maintained within a preset humidity range.

10. The combustible gas concentration detection method according to claim 9, characterized in that: A desiccant or a gas filter is used to control the humidity of the gas entering the combustible gas sensor.

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