A gas detection device and method

Abstract

The application relates to a gas detection device and method. The gas detection device comprises a first sensor for intermittently detecting organic volatile gas based on photoionization technology to collect first gas data, and a second sensor for continuously detecting organic volatile gas based on semiconductor technology to collect second gas data. The first sensor and the second sensor are fused, and the use frequency of the first sensor is reduced by intermittently operating the first sensor, thereby prolonging the service life of the first sensor. A processing module for processing data can construct a calibration model based on at least the first gas data and the second gas data collected at the same time point, and calibrate the second gas data collected by the second sensor in real time based on the calibration model, so as to obtain the detection result of the gas detection device on the organic volatile gas.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and in particular to a gas detection device and method. Background Technology

[0002] VOCs (volatile organic compounds) have a significant impact on human health. When VOC concentrations in the environment reach a certain level, people may experience headaches, nausea, vomiting, and fatigue in a short period. In severe cases, they can cause convulsions, coma, and damage to the liver, kidneys, brain, and nervous system, leading to serious consequences such as memory loss. Outdoor VOCs mainly originate from fuel combustion and transportation; indoor VOCs mainly come from combustion products of coal and natural gas, smoke from smoking, heating, and cooking, as well as emissions from building and decoration materials, furniture, household appliances, cleaning agents, and the human body itself. VOC detection in the air is one of the most basic environmental monitoring procedures. Current technologies typically use semiconductor sensors and PID (Photo Ionization Detector) sensors for gas detection.

[0003] For example, patent CN115598184A discloses a measurement method for an air quality detection system, relating to the field of gas detection. It includes a microcontroller, a temperature and humidity sensor, and a gas sensor. The microcontroller is connected to the temperature and humidity sensor and the gas sensor. The temperature and humidity sensor is used to collect temperature and humidity information, and the gas sensor is used to collect the VOC concentration in the air. After collecting the temperature and humidity information and the VOC concentration, the microcontroller compensates and calibrates the air's VOC concentration based on the temperature and humidity information. This invention, based on the microcontroller's collection of temperature and humidity information and gas VOC concentration, further addresses the existing deficiency of moisture content affecting VOC concentration measurement by enabling the microcontroller to perform compensation calculations on the gas VOC concentration based on the temperature and humidity information, resulting in a more accurate gas VOC concentration value after the calculation.

[0004] Patent CN114487190A discloses a medical human exhaled VOC gas detection device based on an optical PID sensor, including an air inlet, a drying tube, an optical PID sensor, a main controller, and a display. The mixed VOC gas to be detected enters the drying tube through the air inlet. The dried mixed VOC gas is then passed through the optical PID sensor to detect the crude content and composition of the VOC gas. The detection data of crude content and composition are transmitted to the main controller, which transmits the data to the display. The display shows the molecules and their content in the detected mixed VOC gas.

[0005] Patent publication number CN207798618U discloses a gas detection device. The gas detection device includes a semiconductor VOC sensor, a PID sensor, a microcontroller, and a power control circuit. The power control circuit controls the electrical on / off state of the semiconductor VOC sensor and the PID sensor. The microcontroller controls the power control circuit to turn on the PID sensor for gas detection when the semiconductor VOC sensor detects that the concentration of volatile organic compounds in the gas exceeds a preset threshold, and controls the power control circuit to turn off the PID sensor when the semiconductor VOC sensor detects that the concentration of volatile organic compounds in the gas does not exceed the preset threshold.

[0006] Most existing technologies use semiconductor sensors or PID sensors for VOC gas detection. In semiconductor sensors, the resistance of the gas-sensitive material changes with the VOC content (concentration) in the mixed gas at high temperatures. The VOC content (concentration) is indirectly obtained by measuring the resistance of the gas-sensitive material (gas-sensitive resistor). However, in practical applications, the resistance of the gas-sensitive material is also affected by factors such as the moisture content in the mixed gas, temperature changes, and changes in the properties of the gas-sensitive material, resulting in data drift and inaccurate detection results. For example, if the gas-sensitive material uses a metal catalyst that is easily oxidized in air, the catalyst gradually oxidizes and becomes ineffective as the detection time increases, weakening the reaction between the gas-sensitive material and the VOC gas, thus causing data drift in the semiconductor sensor.

[0007] PID sensors, based on photoelectro-ionization technology, use high-energy ultraviolet light to photoionize organic gases. The magnitude of the current generated by the charged ions reflects the gas concentration. PID photoelectro-ionization gas sensors offer advantages such as fast response and accurate measurement. However, their drawbacks are also significant: they are expensive, and the ultraviolet lamps have a limited lifespan; continuous operation significantly reduces the sensor's lifespan. In the field of volatile organic compound (VOC) gas detection, volatilization is a slowly changing process, and the volatilized organic gases cause environmental changes that can affect biological health. Therefore, long-term monitoring of VOC concentrations is necessary to prevent excessively high concentrations from harming organisms. However, the need for long-term VOC monitoring contradicts the reduced lifespan of PID photoelectro-ionization gas sensors due to prolonged use. Furthermore, the ionization energy required for different VOC substances to be photoionized by ultraviolet light varies. Too low an ionization energy will result in inaccurate detection of VOC concentrations, while prolonged operation at high ionization energy will further drastically reduce the sensor's lifespan, leading to wasted resources and costs.

[0008] This invention aims to improve the detection method of VOC gas and proposes a gas detection device and method that can overcome the above-mentioned defects.

[0009] Furthermore, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the applicant studied a large number of documents and patents when making this invention, but due to space limitations, not all details and contents were listed in detail. However, this does not mean that the present invention does not possess the features of these prior art. On the contrary, the present invention already possesses all the features of the prior art, and the applicant reserves the right to add relevant prior art to the background art. Summary of the Invention

[0010] Existing gas detection devices mostly utilize sensors based on photoelectro-ionization technology or semiconductor technology. Photoelectro-ionization sensors offer higher detection accuracy and more precise results for volatile organic compounds compared to semiconductor-based sensors; however, their limited lifespan due to the ultraviolet lamp restricts long-term gas detection. Semiconductor-based sensors, on the other hand, have a longer lifespan and can operate continuously for extended periods, but their results are susceptible to drift due to changes in humidity, temperature, and material properties. Therefore, existing gas detection devices struggle to achieve a compromise between operating time and detection accuracy.

[0011] To address the shortcomings of existing technologies, this invention provides a gas detection device. The gas detection device includes: a first sensor, a second sensor, and a processing module. Preferably, the first sensor intermittently detects volatile organic compounds (VOCs) based on photoelectro-ionization technology to collect first gas data. Preferably, the second sensor continuously detects VOCs based on semiconductor technology to collect second gas data. The processing module is capable of obtaining the difference between the second gas data and the first gas data based on the first gas data collected by the first sensor and the second gas data collected by the second sensor at the same time point. The processing module calibrates the second gas data collected in real-time by the second sensor based on the difference, thereby obtaining the detection result of the gas detection device for VOCs.

[0012] Preferably, the gas detection device provided by the present invention detects gases by integrating a first sensor based on photoelectro-ionization technology and a second sensor based on semiconductor technology. The first sensor based on photoelectro-ionization technology has higher detection accuracy than the second sensor based on semiconductor technology, and its detection results for volatile organic gases are more accurate. However, the first sensor is limited by the lifespan of its ultraviolet lamp, making long-term gas detection difficult. The second sensor based on semiconductor technology has a longer lifespan than the first sensor based on photoelectro-ionization technology and can operate continuously for long-term gas detection. However, its detection results are subject to drift and are easily affected by environmental factors such as temperature. The present invention integrates a first sensor based on photoelectro-ionization technology and a second sensor based on semiconductor technology, wherein the second sensor operates continuously, while the first sensor operates intermittently. Preferably, by making the first sensor operate intermittently, the present invention reduces the frequency of use of the first sensor, thereby extending its lifespan. Furthermore, the present invention can construct a calibration model based on the first gas data collected by the first sensor and the second gas data collected by the second sensor at the same time point, and then calibrate the second gas data collected in real time by the second sensor using the calibration model, thereby achieving long-term accurate gas detection.

[0013] According to a preferred embodiment, the first sensor performs detection according to a first time period, and the second sensor performs detection according to a second time period. Preferably, the second time period is longer than the first time period. The first sensor performs detection intermittently within the first time period of the second sensor within the second time period, while the second sensor performs detection continuously within the second time period. Preferably, within the second time period, the data collected by the second sensor does not drift or drifts within a preset range. Preferably, the first sensor of the present invention performs detection based on the first time period. Compared with existing PID sensor systems or devices, in the same amount of detection time, while ensuring detection accuracy, the working time of the first sensor (PID sensor) is significantly reduced, thus significantly improving the service life of the first sensor.

[0014] According to a preferred embodiment, the gas detection device includes a processing module for processing data. The processing module is at least capable of determining the difference between the second sensor and the first sensor based on the first gas data and the second gas data collected at the same time point. The processing module calibrates the second gas data collected in real-time by the second sensor based on the difference, so that the second gas data collected in real-time by the second sensor is close to the first gas data collected by the first sensor, thereby obtaining the detection result of the gas detection device for volatile organic gases.

[0015] Preferably, the processing module can construct a calibration model based on the difference between the first gas data collected by the first sensor and the second gas data collected by the second sensor at the same time point. The processing module calibrates the second gas data collected in real time by the second sensor based on the calibration model, thereby eliminating measurement errors caused by data drift and other problems of the second sensor.

[0016] According to a preferred embodiment, the first sensor includes an illumination unit that ionizes a gas using ultraviolet light. Preferably, the illumination unit includes a plurality of ultraviolet lamps. The first sensor, in response to control by the processing module, adjusts the number of ultraviolet lamps in the illumination unit to regulate the ionization energy, such that the first sensor always operates by outputting an ionization energy less than or equal to that required for the current gas to be ionized.

[0017] Preferably, since the ionization energy required for different organic volatile gases to be ionized by ultraviolet light is inconsistent, if the ionization energy is too low, the concentration of organic volatile gases cannot be accurately detected. However, long-term operation at high ionization energy will lead to a further sharp decline in the service life of the PID photoelectric ionization gas sensor. In order to ensure detection accuracy, this invention adjusts the ionization energy by adjusting the number of ultraviolet lamps turned on in the illumination unit, so that the first sensor always performs detection work with an output less than or equal to the ionization energy required for the current gas to be ionized. This reduces the lifespan loss of the first sensor caused by long-term operation at high ionization energy and significantly improves the service life of the first sensor.

[0018] According to a preferred embodiment, the processing module is also capable of continuously acquiring second gas data collected by the second sensor. Preferably, the processing module is also capable of adjusting the start-up and shutdown of the first sensor in response to changes in the second gas data. Preferably, when a calibration model has been constructed, the processing module can wake up the first sensor in response to characteristic changes in the second gas data calibrated by the calibration model when the first sensor is in sleep mode.

[0019] Preferably, the present invention can extend the service life of the first sensor by reducing its operating time. Preferably, during gas detection, the present invention can detect second gas data of the environment using a continuously operating second sensor, and activate the first sensor when characteristic changes occur in the second gas data of the environment to obtain first gas data that more accurately reflects the properties of the gas in the environment at that time.

[0020] Preferably, when the gas detection device provided by the present invention is used in fields such as safety monitoring and gas leak early warning, the processing module can activate the first sensor to perform gas detection when the second gas data collected by the second sensor exceeds a preset threshold or abruptly changes after calibration by the calibration model, so as to obtain more accurate first gas data and determine whether the abnormal change in the second gas data is caused by gas or by problems such as data drift of the second sensor, thereby reducing false alarms.

[0021] The present invention also provides a gas detection method. The gas detection method includes: acquiring first gas data of volatile organic compounds using a first sensor based on photoelectro-ionization technology; acquiring second gas data of volatile organic compounds using a second sensor based on semiconductor technology; and calibrating the second gas data using the first gas data acquired at the same time point. Preferably, the first sensor performs detection according to a first time period, and the second sensor performs detection according to a second time period, wherein the second time period is longer than the first time period.

[0022] Preferably, the gas detection method provided by the present invention can perform preliminary gas detection based on the second sensor that can work for a long time, and perform precise gas detection using the first sensor that works intermittently. Furthermore, the present invention can calibrate the second gas data of organic volatile gases collected by the second sensor using the more accurate first gas data of organic volatile gases collected by the first sensor, thereby extending the service life of the first sensor while improving the accuracy of the second gas data of organic volatile gases collected by the second sensor, and thus achieving long-term accurate gas detection.

[0023] The present invention also provides a VOC gas detection device. The gas detection device includes a first sensor and a second sensor respectively connected to a processing module. The first sensor collects first gas data of volatile organic compounds based on photoelectro-ionization technology. The second sensor collects second gas data of volatile organic compounds based on semiconductor technology. The first sensor is configured with several ionization energies to output different ionization energies. The processing module adjusts the ionization energy of the first sensor in a manner that ensures the error between the first gas data and the second gas data is within a desired error range.

[0024] Preferably, the VOCs involved in this invention can be volatile organic compounds that meet the definition of VOCs by the U.S. Environmental Protection Agency (EPA), specifically any carbon compound that participates in atmospheric photochemical reactions other than CO, CO2, H2CO3, metal carbides, metal carbonates and ammonium carbonate.

[0025] Ordinary photoelectric ionization gas sensors cannot analyze the type of gas. They can only detect the gas by adjusting or customizing a photoelectric ionization gas sensor with a corresponding ionization energy after pre-determining the type of gas to be measured. Preferably, this invention uses a first sensor and a second sensor to detect the gas. Furthermore, this invention can adjust the ionization energy of the first sensor based on the second gas data collected by the second sensor. While ensuring detection accuracy, this ensures that the first sensor always operates with an output ionization energy less than or equal to that required to ionize the current gas, thereby reducing the lifespan of the first sensor caused by long-term high ionization energy operation and significantly improving its service life.

[0026] According to a preferred embodiment, the processing module collects the correspondence between the ionization energy and the first gas data by recording the first gas data at different ionization energies of the first sensor, thereby determining the gas type and gas concentration of the organic volatile gas.

[0027] Preferably, when the detected gas is a mixed gas, the processing module of the present invention can analyze and determine the gas composition and gas concentration in the mixed gas based on the ionization energy of the first sensor and the change of the first gas data determined by the current ionization energy. This eliminates the need to pre-customize a specific PID sensor according to the type of gas to be tested, thus significantly expanding the application range of the VOC gas detection device.

[0028] According to a preferred embodiment, the first sensor includes an illumination unit that ionizes a gas using ultraviolet light and a detection unit that processes the ionization signal. Preferably, the illumination unit includes a plurality of ultraviolet lamps. Preferably, the first sensor adjusts the number of ultraviolet lamps in the illumination unit to adjust the ionization energy in response to the control of the processing module, so that the detection unit detects the first gas data at different ionization energies.

[0029] Preferably, the present invention can adjust the ionization energy of the illumination unit by activating different numbers and positions of ultraviolet lamps, and drive the ultraviolet lamps to operate in a rotating manner, which significantly reduces the operating time of a single ultraviolet lamp in the illumination unit, thereby extending the service life of the ultraviolet lamps in the illumination unit and thus improving the service life of the first sensor.

[0030] This invention also provides a VOC gas detection method. The VOC gas detection method includes: acquiring first gas data of volatile organic compounds using a first sensor based on photoelectro-ionization technology; acquiring second gas data of volatile organic compounds using a second sensor based on semiconductor technology; adjusting the ionization energy of the first sensor in a manner that ensures the error between the first gas data and the second gas data is within a desired error range; and acquiring the correspondence between the ionization energy and the first gas data by recording the first gas data at different ionization energies, thereby determining the gas type and concentration of the volatile organic compounds. Preferably, the first sensor performs detection according to a first time period, and the second sensor performs detection according to a second time period, wherein the second time period is longer than the first time period.

[0031] Preferably, in this invention, the first sensor performs detection based on a first time period. Compared with existing PID sensor systems or devices, the working time of the first sensor is significantly reduced while ensuring detection accuracy during the same detection period. Furthermore, the first sensor always performs detection by providing less than or equal to the ionization energy required for the current gas to be ionized, thereby reducing the wear and tear of the first sensor from the perspective of time and energy output and extending the service life of the first sensor.

[0032] The present invention can also analyze and determine the gas composition and gas concentration based on the ionization energy of the first sensor and the change of the first gas data of the first sensor at the current ionization energy, without the need to pre-customize a specific PID sensor according to the type of gas to be measured, so that it can be used to identify and detect the concentration of different types of gases in a mixed gas. Attached Figure Description

[0033] Figure 1 This is a simplified schematic diagram of a gas detection device according to a preferred embodiment of the present invention;

[0034] Figure 2 This is a simplified schematic diagram of the first sensor according to a preferred embodiment of the present invention;

[0035] Figure 3 This is a simplified schematic diagram of a lighting unit according to a preferred embodiment of the present invention.

[0036] List of reference numerals

[0037] 100: First sensor; 110: Illumination unit; 111: First lamp array; 112: Second lamp array; 113: Third lamp array; 114: Fourth lamp array; 120: Detection unit; 200: Second sensor; 300: Processing module; 400: Air inlet; 500: Air pump. Detailed Implementation

[0038] The following is in conjunction with the appendix Figures 1 to 3 Please provide a detailed explanation.

[0039] Example 1

[0040] Most existing technologies use semiconductor sensors or PID sensors for VOC gas detection. In semiconductor sensors, the resistance of the gas-sensitive material changes with the VOC content (concentration) in the mixed gas at high temperatures. The VOC content (concentration) is indirectly obtained by measuring the resistance of the gas-sensitive material (gas-sensitive resistor). However, in practical applications, the gas-sensitive resistor is also affected by the moisture content in the mixed gas.

[0041] PID sensors are based on photoelectro-ionization technology. They use high-energy ultraviolet light to photoionize organic gases, and the magnitude of the current generated by the charged ions reflects the gas concentration. PID photoelectro-ionization gas sensors have the advantages of fast response and accurate measurement, but their disadvantages are also quite obvious. PID photoelectro-ionization gas sensors are expensive, and the ultraviolet lamp has a limited lifespan; continuous operation of the PID photoelectro-ionization gas sensor will significantly reduce its lifespan.

[0042] This embodiment provides a gas detection device. Preferably, the gas detection device includes: a first sensor 100, a second sensor 200, and a processing module 300. Preferably, the first sensor 100 detects volatile organic compounds (VOCs) based on photoelectro-ionization technology to collect first gas data. Preferably, the second sensor 200 detects VOCs based on semiconductor technology to collect second gas data. The processing module 300, used for processing the data, is capable of constructing a calibration model based at least on the first gas data collected by the first sensor 100 and the second gas data collected by the second sensor 200 at the same time point. The processing module 300 calibrates the second gas data collected in real time by the second sensor 200 based on the calibration model, thereby obtaining the detection result of the gas detection device for VOCs. Preferably, the first gas data and the second gas data include gas concentration values.

[0043] See Figure 1 Preferably, the gas detection device may include an air inlet 400, a gas pump 500, a first sensor 100, a second sensor 200, and a processing module 300. Preferably, the first sensor 100 and the second sensor 200 are disposed between the air inlet 400 and the gas pump 500, and connected via a gas delivery pipe. Under the action of the gas pump 500, the gas to be detected flows from the air inlet 400 along the gas delivery pipe, passing through the first sensor 100 and the second sensor 200 for detection.

[0044] Preferably, Figure 1 In the gas detection device shown, the positions of the first sensor 100 and the second sensor 200 can be interchanged. Preferably, the gas to be detected can pass through the first sensor 100 first and then the second sensor 200, or vice versa. Alternatively, the gas to be detected can enter the first sensor 100 and the second sensor 200 separately by setting a diversion channel or a separate air inlet channel. Preferably, the gas detection by the first sensor 100 and the second sensor 200 can be performed either in series or in parallel.

[0045] Preferably, the processing module 300 may be an intelligent processing device such as a computer, or a logic gate array, controller and arithmetic logic unit, digital signal processor, microcomputer, programmable logic controller, field-programmable gate array, programmable logic array, microprocessor, or any other device or combination of devices configured to respond to and execute instructions in a defined manner to achieve the desired result.

[0046] Preferably, the second sensor 200 can be a semiconductor gas sensor that detects volatile organic gases based on semiconductor technology. The semiconductor gas sensor obtains the gas concentration and type by detecting the change in the resistance value of the gas-sensitive material under high temperature conditions.

[0047] Preferably, the first sensor 100 can be a PID sensor for detecting volatile organic compounds based on photoelectro-ionization technology. Preferably, the PID sensor includes an ultraviolet light source and a detector. The ultraviolet light source emits energy to ionize the gas to be measured. Volatile organic compounds generate positive and negative ions under the excitation of the ultraviolet light source, which can then be easily detected by the detector. When gas molecules absorb high-energy ultraviolet radiation from the ultraviolet light source, they become ionized. Under this excitation, the molecules generate negative electrons and form positive ions. These ionized particles generate a current through the detector, and the magnitude of the current reflects the concentration of the gas.

[0048] The first sensor 100 uses a PID photoelectric ionization gas sensor, which has the advantages of fast response and accurate measurement. However, its disadvantages are also quite obvious: the PID photoelectric ionization gas sensor is expensive, and the ultraviolet lamp has a limited lifespan; continuous operation of the PID photoelectric ionization gas sensor will significantly reduce its lifespan. The second sensor 200 uses a semiconductor gas sensor with a long lifespan, but the high-temperature operating conditions of its gas-sensitive material make the second sensor 200 susceptible to interference from moisture in the gas. Furthermore, with increasing usage time, the second sensor 200 will also experience data drift, increasing the error of the detected data.

[0049] Preferably, the gas detection device provided in this embodiment detects gases by integrating a first sensor 100 based on photoelectro-ionization technology and a second sensor 200 based on semiconductor technology. The first sensor 100 based on photoelectro-ionization technology has higher detection accuracy than the second sensor 200 based on semiconductor technology, and its detection results for volatile organic gases are more accurate. However, the first sensor 100 is limited by the lifespan of its ultraviolet lamp, making long-term gas detection difficult. The second sensor 200 based on semiconductor technology has a longer lifespan than the first sensor 100 based on photoelectro-ionization technology and can operate continuously for long-term gas detection. However, its detection results are subject to drift and are easily affected by environmental factors such as temperature. This embodiment integrates the first sensor 100 based on photoelectro-ionization technology and the second sensor 200 based on semiconductor technology, wherein the second sensor 200 operates continuously, while the first sensor 100 operates intermittently. Preferably, by making the first sensor 100 operate intermittently, this embodiment reduces the usage frequency of the first sensor 100, thereby extending its lifespan. Furthermore, this embodiment can construct a calibration model based on the first gas data collected by the first sensor 100 and the second gas data collected by the second sensor 200 at the same time point, and then calibrate the second gas data collected by the second sensor 200 in real time through the calibration model, thereby achieving long-term accurate gas detection.

[0050] Preferably, the first sensor 100 performs detection according to a first time period, and the second sensor 200 performs detection according to a second time period, wherein the second time period is longer than the first time period.

[0051] Preferably, the first sensor 100 performs detection intermittently within a first time period during a second time period of the second sensor 200, while the second sensor 200 performs detection continuously within a second time period.

[0052] Preferably, the duration of the second time period can be more than twice the duration of the first time period, that is, within the second time period, the first sensor 100 can perform at least one first gas data acquisition operation with a duration of the first time period. Preferably, after performing one first gas data acquisition operation with a duration of the first time period, the first sensor 100 can enter a sleep state until the next first gas data acquisition.

[0053] Preferably, the second time period may include several first time periods. Preferably, within a second time period, the first sensor 100 may intermittently perform detection work by acquiring first gas data in one first time period, then going into a dormant state for one first time period, and then acquiring first gas data in another first time period. Preferably, within a second time period, the first sensor 100 may acquire first gas data in the first first time period, and then go into a dormant state in subsequent first time periods until the gas detection device enters a new second time period.

[0054] Preferably, during the second time period, the data collected by the second sensor 200 will not drift or will drift within a preset range.

[0055] Preferably, in the first time period of the second time period, the processing module 300 can acquire the first gas data collected by the first sensor 100 and the second gas data collected by the second sensor 200, and construct a calibration model based on the first gas data and the second gas data within the first time period. Preferably, the calibration model can adjust the second gas data to be the same as or close to the value of the first data. During the remaining time of the second time period, the processing module 300 can use the calibration model to calibrate the second gas data collected by the second sensor 200, so that the accuracy of the calibrated second gas data is close to that of the first gas data collected by the first sensor 100.

[0056] In the new second time period, the processing module 300 can acquire the first gas data collected by the first sensor 100 and the second gas data collected by the second sensor 200 in the first first time period to update the calibration model, and use the updated calibration model to calibrate the second gas data collected by the second sensor 200 in the remaining time of the second time period.

[0057] Preferably, the processing module 300 can also acquire the first gas data collected by the first sensor 100 and the second gas data collected by the second sensor 200 during the first time period when the first sensor 100 is working to construct or update a calibration model, and use the constructed or updated calibration model to calibrate the second gas data collected by the second sensor 200 when the first sensor 100 is in sleep mode. For example, when the first time period is one day and the second time period is one week, the first sensor 100 can collect the first gas data only on Monday, and the second sensor 200 can continuously collect the second gas data from Monday to Sunday. The processing module 300 can acquire the first gas data collected by the first sensor 100 on Monday and the second gas data collected by the second sensor 200 on Monday to construct a calibration model, and use the calibration model to calibrate the second gas data collected by the second sensor 200 from Tuesday to Sunday. After entering the second week, due to data drift of the second sensor 200, the previously constructed calibration model may have become invalid, and the processing module 300 needs to acquire the first gas data collected by the first sensor 100 on Monday of the second week and the second gas data collected by the second sensor 200 on Monday of the second week to update the calibration model.

[0058] Preferably, in this embodiment, the first sensor 100 performs detection based on a first time period. Compared with existing PID sensor systems or devices, the working time of the first sensor 100 (PID sensor) is significantly reduced while ensuring detection accuracy during the same detection period, thus significantly improving the service life of the first sensor 100.

[0059] Preferably, the processing module 300 can acquire first gas data collected by the first sensor 100 and second gas data collected by the second sensor 200 at the same time point as the first sensor 100 acquiring the first gas data to construct a calibration model. Preferably, the processing module 300 can construct a calibration model based on the first gas data and the second gas data at the same acquisition time point. Preferably, the processing module 300 can establish a calibration model based on the difference between the first gas data and the second gas data at the same acquisition time point, and then use the calibration model to calibrate the second gas data collected by the second sensor 200.

[0060] Preferably, the processing module 300 obtains the difference between the second gas data collected by the second sensor 200 and the more accurate first gas data collected by the first sensor 100, and uses the difference to compensate for the error of the second gas data subsequently collected by the second sensor 200, thereby obtaining a more accurate detection result when only the second sensor 200 is used to collect the second gas data.

[0061] Preferably, the first sensor 100 performs detection intermittently within a first time period during a second time period of the second sensor 200, while the second sensor 200 performs detection continuously within the second time period. Preferably, when the first sensor 100 acquires first gas data, the processing module 300 updates the calibration model. Preferably, the processing module 300 updates the calibration model by acquiring second gas data acquired by the second sensor 200 at the same time point when the first sensor 100 acquires the first gas data, thereby updating the difference between the first gas data and the second gas data, thus eliminating errors caused by data drift of the second sensor 200 and avoiding distortion of the detection results of the gas detection device.

[0062] Preferably, the first sensor 100 intermittently collects first gas data, and the second sensor 200 collects second gas data in real time. Preferably, the processing module 300 can also continuously acquire the second gas data collected by the second sensor 200. Preferably, the processing module 300 can also adjust the start and stop of the first sensor 100 in response to changes in the second gas data.

[0063] Preferably, when a calibration model has been constructed, the processing module 300 can wake up the first sensor 100 in response to a characteristic change in the second gas data calibrated by the calibration model when the first sensor 100 is in sleep mode.

[0064] Preferably, in this embodiment, the service life of the first sensor 100 can be extended by reducing the operating time of the first sensor 100. Preferably, when performing gas detection, in this embodiment, the second gas data of the gas in the environment can be detected by the continuously operating second sensor 200, and when the second gas data of the gas in the environment shows a characteristic change after calibration by the calibration model, the first sensor 100 is activated to obtain first gas data that can more accurately reflect the properties of the gas in the environment at this time.

[0065] Preferably, when the gas detection device provided in this embodiment is used in fields such as safety monitoring and gas leak early warning, the processing module 300 can continuously acquire the second gas data collected by the second sensor 200 and calibrate the second gas data using a calibration model, thereby obtaining the change curve of the second gas data after calibration and detection time. The processing module 300 can also adjust the start and stop of the first sensor 100 based on the characteristic changes of the change curve of the second gas data after calibration.

[0066] Preferably, the processing module 300 can perform routine monitoring via the second sensor 200. When the second gas data, after being calibrated by the calibration model, exhibits abrupt changes or exceeds a preset threshold, the processing module 300 can activate the first sensor 100 for detection to determine whether the abnormal change in the second gas data is caused by the gas.

[0067] When using the second sensor 200 for gas detection, data drift from the semiconductor sensor may cause the processing module 300 to trigger an alarm if the measurement error of the second gas data collected by the second sensor 200 exceeds a preset threshold, resulting in a false alarm. Preferably, in this embodiment, the processing module 300 can activate the first sensor 100 for gas detection when the second gas data collected by the second sensor 200 exceeds the preset threshold, to obtain more accurate first gas data and thus determine that the gas in the environment is within a safe range. Furthermore, since the second gas data collected by the second sensor 200 is prone to errors due to data drift, directly using the second gas data collected by the second sensor 200 to trigger the first sensor 100 for gas detection results in low detection accuracy. Preferably, this embodiment uses a calibration model to calibrate the second gas data, and triggers the first sensor 100 using the calibrated second gas data, thereby improving the accuracy of the wake-up timing. Preferably, in this embodiment, the start-up and shutdown of the first sensor 100 are adjusted by the second gas data calibrated by the calibration model. This not only extends the service life of the first sensor 100 by reducing its working time, but also, when performing gas detection, this embodiment can activate the first sensor 100 when characteristic changes occur in the second gas data calibrated by the calibration model in the environment, thereby obtaining first gas data that more accurately reflects the gas properties in the environment at that time, thus reducing false alarms.

[0068] Example 2

[0069] This embodiment provides a gas detection method. The gas detection method includes: collecting first gas data of volatile organic compounds using a first sensor 100 based on photoelectro-ionization technology; collecting second gas data of volatile organic compounds using a second sensor 200 based on semiconductor technology; and calibrating the second gas data using the first gas data collected at the same time point. Preferably, the first sensor 100 performs detection according to a first time period, and the second sensor 200 performs detection according to a second time period, wherein the second time period is longer than the first time period. Preferably, the first gas data and the second gas data include gas concentration values.

[0070] Preferably, the gas detection method provided in this embodiment can perform preliminary gas detection based on a second sensor 200 that can work for a long time, and perform precise gas detection using a first sensor 100 that works intermittently. Furthermore, this embodiment can calibrate the second gas data of organic volatile gases collected by the second sensor 200 using the more accurate first gas data of organic volatile gases collected by the first sensor 100, thereby extending the service life of the first sensor 100 while improving the accuracy of the second gas data of organic volatile gases collected by the second sensor 200, and thus achieving long-term accurate gas detection.

[0071] The first sensor 100 uses a PID photoelectric ionization gas sensor, which has the advantages of fast response and accurate measurement. However, its disadvantages are also quite obvious: the PID photoelectric ionization gas sensor is expensive, and the ultraviolet lamp has a limited lifespan; continuous operation of the PID photoelectric ionization gas sensor will significantly reduce its lifespan. The second sensor 200 uses a semiconductor gas sensor with a long lifespan, but the high-temperature operating conditions of its gas-sensitive material make the second sensor 200 susceptible to interference from moisture in the gas. Furthermore, with increasing usage time, the second sensor 200 will also experience data drift, increasing the error of the detected data.

[0072] Preferably, in this embodiment, a calibration model can be constructed by acquiring first gas data collected by the first sensor 100 and second gas data collected by the second sensor 200 at the same time point as the first gas data collected by the first sensor 100. Preferably, in this embodiment, a calibration model can be constructed based on the difference between the first gas data and the second gas data at the same acquisition time point, and the second gas data collected by the second sensor 200 can be calibrated using the calibration model.

[0073] Preferably, the calibration model can calibrate the second gas data collected by the second sensor 200 by obtaining the difference between the second gas data collected by the second sensor 200 and the more accurate first gas data collected by the first sensor 100 at the same collection time point, and using this difference to compensate for the error of the second gas data collected by the second sensor 200 in the future, so as to obtain a more accurate detection result when only the second sensor 200 is used to collect the second gas data.

[0074] Preferably, in this embodiment, the first sensor 100 performs detection intermittently within a first time period during a second time period of the second sensor 200, while the second sensor 200 performs detection continuously within a second time period. Preferably, when the first sensor 100 collects first gas data, this embodiment acquires second gas data collected by the second sensor 200 at the same time point, thereby updating the difference between the first and second gas data and eliminating errors caused by data drift or other issues caused by the second sensor 200.

[0075] Preferably, the first sensor 100 intermittently collects first gas data, while the second sensor 200 collects second gas data in real time. Preferably, this embodiment can also continuously acquire the second gas data collected by the second sensor 200, thereby obtaining a curve showing the change in the second gas data relative to the detection time. Preferably, this embodiment can also adjust the start / stop of the first sensor 100 based on the curve.

[0076] Preferably, in this embodiment, the service life of the first sensor 100 can be extended by reducing the operating time of the first sensor 100. Preferably, when performing gas detection, in this embodiment, the second gas data of the gas in the environment can be detected by the continuously operating second sensor 200, and when the second gas data of the gas in the environment shows characteristic changes, the first sensor 100 is activated to obtain first gas data that can more accurately reflect the properties of the gas in the environment at this time.

[0077] Preferably, in this embodiment, routine monitoring can be performed using the second sensor 200. When the second gas data collected by the second sensor 200 shows a sudden change or exceeds a preset threshold, this embodiment can activate the first sensor 100 for detection to determine whether the abnormal change in the second gas data is caused by the gas.

[0078] Example 3

[0079] This embodiment provides a VOC gas detection device. The gas detection device includes a first sensor 100 and a second sensor 200, both connected to a processing module 300. The first sensor 100 collects first gas data of volatile organic compounds based on photoelectro-ionization technology. The second sensor 200 collects second gas data of volatile organic compounds based on semiconductor technology. The first sensor 100 is configured with several ionization energies to output different ionization energies. The processing module 300 adjusts the ionization energy of the first sensor 100 in a manner that ensures the error between the first gas data and the second gas data is within a desired error range.

[0080] Furthermore, ordinary photoelectric ionization gas sensors cannot analyze the type of gas. They can only determine the type of gas to be measured in advance, and then adjust or customize a photoelectric ionization gas sensor with a corresponding ionization energy to detect the gas and obtain data for that type of gas. Preferably, this embodiment uses a first sensor 100 and a second sensor 200 to detect the gas. In this embodiment, the ionization energy of the first sensor 100 can be adjusted based on the second gas data collected by the second sensor 200. While ensuring detection accuracy, this ensures that the first sensor 100 always operates with an output of less than or equal to the ionization energy required to ionize the current gas, thereby reducing the lifespan of the first sensor 100 caused by long-term high ionization energy operation and significantly improving its service life.

[0081] Preferably, the processing module 300 obtains the correspondence between the ionization energy and the first gas data by recording the first gas data of the first sensor 100 at different ionization energies, thereby determining the gas type and gas concentration of the organic volatile gas.

[0082] Preferably, when the detected gas is a mixed gas, the processing module 300 of this embodiment can analyze and determine the gas composition and gas concentration in the mixed gas based on the ionization energy of the first sensor 100 and the change of the first gas data determined by the current ionization energy. This eliminates the need to pre-customize a specific PID sensor according to the type of gas to be tested, thus significantly expanding the application range of the VOC gas detection device.

[0083] See Figure 2 Preferably, the first sensor 100 includes an illumination unit 110 that ionizes the gas using ultraviolet light and a detection unit 120 that processes the ionization signal. Preferably, the illumination unit 110 includes a plurality of ultraviolet lamps. Preferably, the first sensor 100 adjusts the number of ultraviolet lamps in the illumination unit 110 to adjust the ionization energy in response to the control of the processing module 300, so that the detection unit 120 detects the first gas data at different ionization energies.

[0084] Preferably, in this embodiment, the ionization energy of the illumination unit 110 can be adjusted by activating different numbers and positions of ultraviolet lamps, and the ultraviolet lamps can be driven to run in a rotating manner, which significantly reduces the operating time of a single ultraviolet lamp in the illumination unit 110, thereby extending the service life of the ultraviolet lamps in the illumination unit 110 and thus improving the service life of the first sensor 100.

[0085] See Figure 3Preferably, the illumination unit 110 may include a uniformly distributed first lamp array 111, a second lamp array 112, a third lamp array 113, and a fourth lamp array 114. Preferably, the illumination unit 110 activates one of the lamp arrays individually at level one ionization energy, activates two lamp arrays at level two ionization energy, activates three lamp arrays at level three ionization energy, and activates four lamp arrays at level four ionization energy. Preferably, the illumination unit 110 can adjust the ionization energy by adjusting the number of lamp arrays. Preferably, the ionization energy of the illumination unit 110 increases as the number of activated lamp arrays increases.

[0086] Preferably, the processing module 300 can call the light emission modes of the first lamp array 111, the second lamp array 112, the third lamp array 113 and the fourth lamp array 114 in the illumination unit 110 based on the rotation method, so that the average working time of the ultraviolet lamps in each array of the illumination unit 110 is the same. Preferably, the first lamp array 111, the second lamp array 112, the third lamp array 113, and the fourth lamp array 114 are arranged in sequence. Within one cycle, a certain sequence is sequentially used to perform the time required for measuring an ionization energy level, and then it is sequentially placed at the end of the queue. For example, within one cycle, the first ionization energy is called by the first lamp array 111. After the measurement is completed, the second ionization energy needs to be called. At this time, the first lamp array 111 is placed after the fourth lamp array 114, and the second lamp array 112 and the third lamp array 113 are called at the same time. If the third ionization energy also needs to be called, the second lamp array 112 and the third lamp array 113 are first placed after the first lamp array 111, and then the fourth lamp array 114, the first lamp array 111, and the second lamp array 112 are called. If the current ionization energy level meets the requirements, the measurement is stopped, and the fourth lamp array 114, the first lamp array 111, and the second lamp array 112 are placed after the third lamp array 113. When calling the lamp arrays in the next cycle, they are called according to the current arrangement order.

[0087] Preferably, when the first gas data and the second gas data are within the expected error range, it indicates that the current ionization energy level of the first sensor 100 is capable of ionizing all gases in the mixed gas. The processing module 300 analyzes the changes in the first gas data measured by the first sensor 100 at each ionization energy level to distinguish the types of gases that can be ionized by the corresponding ionization energy level, and derives the concentration of the corresponding gas based on the change in gas concentration value.

[0088] PID sensors have high detection accuracy, while semiconductor sensors have a long service life and can work continuously. This embodiment uses a fusion of the two sensors, allowing the semiconductor sensor to work continuously while the PID sensor works intermittently.

[0089] This embodiment employs a fusion of two sensors to increase the selectivity of gas measurements. In detecting difficult-to-ionize gases, such as formaldehyde: because VOC gases require a certain electron potential for ionization by ultraviolet lamps, but some gases like formaldehyde have very high ionization energies, making PID ultraviolet lamps difficult to ionize them, the PID sensor will not register a reading, while the semiconductor sensor will show a clear reading. Therefore, fusing the two signals and using ultraviolet lamps of different energies can distinguish between various gases.

[0090] This embodiment uses a two-sensor fusion method to increase the PID lifespan: the semiconductor sensor works continuously to detect changes in various VOC gases in the environment. When a significant abnormal value of VOC gas appears, such as exceeding the warning value, the PID sensor is activated to obtain an accurate reading of the VOC gas in the environment at that time.

[0091] This embodiment also uses a two-sensor fusion method to calibrate semiconductor sensor readings and solve the baseline drift problem of semiconductor sensors: the PID sensor operates intermittently, such as working for five minutes every hour. The data from these five minutes can be used to calibrate the semiconductor sensor readings and solve typical problems in semiconductor sensors, such as baseline drift.

[0092] Example 4

[0093] This embodiment provides a VOC gas detection method. The VOC gas detection method includes: collecting first gas data of volatile organic compounds using a first sensor 100 based on photoelectro-ionization technology; collecting second gas data of volatile organic compounds using a second sensor 200 based on semiconductor technology; adjusting the ionization energy of the first sensor 100 in a manner that ensures the error between the first gas data and the second gas data is within a desired error range; and obtaining the correspondence between the ionization energy and the first gas data by recording the first gas data at different ionization energies, thereby determining the gas type and concentration of the volatile organic compounds. Preferably, the first sensor 100 performs detection according to a first time period, and the second sensor 200 performs detection according to a second time period, wherein the second time period is longer than the first time period.

[0094] Preferably, in this embodiment, the first sensor 100 performs detection based on a first time period. Compared with existing PID sensor systems or devices, the working time of the first sensor 100 is significantly reduced while ensuring detection accuracy during the same detection period. Furthermore, the first sensor 100 always performs detection by providing less than or equal to the ionization energy required for the current gas to be ionized, thereby reducing the wear and tear of the first sensor 100 from the perspectives of time and energy output, and thus extending the service life of the first sensor 100.

[0095] This embodiment can also analyze and determine the gas composition and gas concentration based on the ionization energy of the first sensor 100 and the change of the first gas data of the first sensor 100 at the current ionization energy. It does not require pre-customizing a specific PID sensor according to the type of gas to be measured, so it can be used to identify and detect the concentration of different types of gases in a mixed gas.

[0096] Preferably, in this embodiment, the correspondence between the ionization energy and the first gas data is obtained by recording the first gas data of the first sensor 100 at different ionization energies, thereby determining the gas type and gas concentration of the organic volatile gas.

[0097] Preferably, when the gas being detected is a mixture, this embodiment can analyze the gas composition and concentration in the mixture based on the ionization energy of the first sensor 100 and the change in the first gas data determined by the current ionization energy. This eliminates the need to pre-customize a specific PID sensor according to the type of gas to be tested, thus significantly expanding the application range of the VOC gas detection device.

[0098] It should be noted that the specific embodiments described above are exemplary. Those skilled in the art can devise various solutions inspired by the disclosure of this invention, and these solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification and its accompanying drawings are illustrative and do not constitute a limitation on the claims. The scope of protection of this invention is defined by the claims and their equivalents. Throughout the text, features introduced by "preferred" are merely optional and should not be construed as mandatory. Therefore, the applicant reserves the right to abandon or delete relevant preferred features at any time. This specification contains multiple inventive concepts. Phrases such as "preferred," "according to a preferred embodiment," or "optionally" indicate that the corresponding paragraph discloses an independent concept. The applicant reserves the right to file divisional applications based on each inventive concept.

Claims

1. A gas detection device, characterized in that, The gas detection device includes: The first sensor (100) intermittently detects volatile organic gases based on photoelectro-ionization technology to collect first gas data; The second sensor (200) continuously detects volatile organic gases based on semiconductor technology to collect second gas data; Processing module (300) for processing data; The processing module (300) is at least able to determine the difference between the second sensor (200) and the first sensor (100) based on the first gas data and the second gas data collected at the same time point; The processing module (300) calibrates the second gas data collected in real time by the second sensor (200) based on the difference, so that the second gas data collected in real time by the second sensor (200) can be close to the first gas data collected by the first sensor (100).

2. The gas detection device according to claim 1, characterized in that, The first sensor (100) performs detection according to a first time period, and the second sensor (200) performs detection according to a second time period, wherein the second time period is longer than the first time period; The first sensor (100) performs detection intermittently within a first time period during a second time period of the second sensor (200), while the second sensor (200) performs detection continuously within a second time period, thereby reducing the working time of the first sensor (100) and extending its service life.

3. The gas detection device according to claim 2, characterized in that, The processing module (300) can also continuously acquire the second gas data collected by the second sensor (200), and the processing module (300) can also adjust the start and stop of the first sensor (100) in response to changes in the second gas data, thereby extending the service life of the first sensor (100) by reducing the working time of the first sensor (100).

4. The gas detection device according to claim 3, characterized in that, The first sensor (100) includes an illumination unit (110) that ionizes a gas using ultraviolet light, wherein the illumination unit (110) includes a plurality of ultraviolet lamps; The first sensor (100) responds to the control of the processing module (300) to adjust the number of ultraviolet lamps turned on in the illumination unit (110) to adjust the ionization energy, so that the first sensor (100) always performs detection in a manner that outputs less than or equal to the ionization energy required for the current gas to be ionized.

5. A gas detection method, characterized in that, The gas detection method includes: First gas data of organic volatile gases are collected using a first sensor (100) based on photoelectro-ionization technology; Second gas data of volatile organic compounds are collected using a second sensor (200) based on semiconductor technology; The first sensor (100) performs detection according to a first time period, and the second sensor (200) performs detection according to a second time period, wherein the second time period is longer than the first time period. The second gas data is calibrated using the first gas data collected at the same time point.

6. A VOC gas detection device, characterized in that, The gas detection device includes a first sensor (100) and a second sensor (200) respectively connected to the processing module (300); The first sensor (100) collects first gas data of volatile organic compounds based on photoelectro-ionization technology; The second sensor (200) collects second gas data of volatile organic compounds based on semiconductor technology; The first sensor (100) is capable of outputting ionization energy of different magnitudes; The processing module (300) adjusts the ionization energy of the first sensor (100) in such a way that the error between the first gas data and the second gas data is within the desired error range.

7. The VOC gas detection device according to claim 6, characterized in that, The processing module (300) obtains the correspondence between the ionization energy and the first gas data by recording the first gas data of the first sensor (100) at different ionization energies, thereby determining the gas type and gas concentration of the organic volatile gas.

8. The VOC gas detection device according to claim 6 or 7, characterized in that, The first sensor (100) includes an illumination unit (110) that ionizes a gas using ultraviolet light and a detection unit (120) that processes the ionization signal. The illumination unit (110) includes a plurality of ultraviolet lamps; The first sensor (100) responds to the control of the processing module (300) to adjust the number of ultraviolet lamps turned on in the illumination unit (110) to adjust the ionization energy, so that the detection unit (120) can detect the first gas data under different ionization energies.

9. A method for detecting VOC gas, characterized in that, The VOC gas detection method includes: First gas data of organic volatile gases are collected using a first sensor (100) based on photoelectro-ionization technology; Second gas data of volatile organic compounds are collected using a second sensor (200) based on semiconductor technology; The ionization energy of the first sensor (100) is adjusted in such a way that the error between the first gas data and the second gas data is within the desired error range; The correspondence between the ionization energy and the first gas data is obtained by recording the first gas data of the first sensor (100) at different ionization energies, thereby determining the gas type and gas concentration of the organic volatile gas; The first sensor (100) performs detection according to a first time period, and the second sensor (200) performs detection according to a second time period, wherein the second time period is longer than the first time period.

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