Carbon dioxide real-time monitoring system based on Internet of Things

Abstract

The invention relates to the technical field of gas informatization monitoring, in particular to a carbon dioxide real-time monitoring system based on the Internet of Things. Carbon dioxide concentration and environment temperature and humidity are acquired based on a carbon dioxide sensor and a temperature and humidity sensor, and the sensors are periodically calibrated; and communication data transmission is carried out based on the transmission mode switching module, so that data transmission is more accurate and complete, compensation calculation is carried out on the carbon dioxide concentration data through the environment temperature and humidity data, and thus the obtained carbon dioxide concentration is more accurate. Whether the carbon dioxide concentration needs to be adjusted or not is accurately determined subsequently based on the carbon dioxide compensation value or the carbon dioxide compensation value increasing rate; and determining whether the monitoring state is qualified or not based on the average descent speed of the carbon dioxide compensation value within the preset duration after starting adjustment and the carbon dioxide compensation value at the end of the preset duration, and adjusting related parameters based on the monitoring state. The monitoring efficiency of carbon dioxide is improved.

Description

Technical Field

[0001] This invention relates to the technical field of gas information monitoring, and in particular to a real-time carbon dioxide monitoring system based on the Internet of Things. Background Technology

[0002] Carbon dioxide (CO2) is a key gas affecting human health and agricultural production efficiency. In indoor environments, excessively high CO2 concentrations can cause dizziness and difficulty concentrating; excessive CO2 concentrations in industrial workshops can lead to safety accidents; and in agricultural greenhouses, CO2 concentrations directly affect crop photosynthetic efficiency. Therefore, real-time and accurate monitoring of CO2 concentrations is of great importance.

[0003] Existing CO2 monitoring systems have the following shortcomings: low detection accuracy, significant influence from temperature and humidity, sensor drift after long-term use, and lack of effective compensation and calibration mechanisms; limited data transmission methods, mostly relying on single WiFi or wired transmission, which cannot adapt to the distance and power consumption requirements of different scenarios, and high data transmission latency, with massive amounts of data easily causing bandwidth congestion when directly uploaded to the cloud; and weak fault identification capabilities, failing to detect sensor or transmission module failures in a timely manner, affecting monitoring reliability.

[0004] Chinese Patent Publication No. CN108983687A discloses an Internet of Things (IoT) system for monitoring carbon dioxide concentration in greenhouses, comprising a signal analysis and acquisition module, a data storage module, a sensor module, and an acquisition and monitoring module; the signal analysis and acquisition module, the data storage module, and the sensor module are connected in sequence; the acquisition and monitoring module is connected to the data storage module and the sensor module respectively.

[0005] It is evident that existing technologies have the following problems: the accuracy and response of existing carbon dioxide monitoring systems are low, resulting in low monitoring efficiency. Summary of the Invention

[0006] To address this issue, the present invention provides a real-time carbon dioxide monitoring system based on the Internet of Things, which overcomes the problems of low accuracy and slow response in existing carbon dioxide monitoring systems, resulting in low monitoring efficiency.

[0007] To achieve the above objectives, the present invention provides a real-time carbon dioxide monitoring system based on the Internet of Things, comprising: The acquisition unit includes a carbon dioxide sensor for acquiring carbon dioxide concentration data, a temperature and humidity sensor for acquiring ambient temperature and humidity data, and a calibration module for periodically calibrating the carbon dioxide sensor and the temperature and humidity sensor based on a gas concentration curve plotted according to a preset standard carbon dioxide concentration. An edge processing unit includes a transmission mode switching module for transmitting data collected by the acquisition unit, and a calculation module for performing compensation calculations on the carbon dioxide concentration data based on the ambient temperature and humidity data to obtain a carbon dioxide compensation value. The detection unit is used to determine whether to adjust the carbon dioxide concentration based on the carbon dioxide compensation value and a preset safety threshold, or the rate of increase of the carbon dioxide compensation value within a preset time. The analysis unit is used to determine whether the monitoring status is qualified based on the average rate of decrease of the carbon dioxide compensation value within a preset time after the adjustment measures are initiated and the carbon dioxide compensation value at the end of the preset time. It also adjusts the preset time based on the monitoring status and adjusts the parameters in the calculation module based on the monitoring status after the preset time is adjusted.

[0008] Furthermore, the transmission mode switching module is also used to automatically determine the transmission mode based on the transmission signal strength and transmission time delay.

[0009] Furthermore, the calculation module is used to correct the carbon dioxide concentration using a compensation model, based at least on a preset reference temperature and a preset reference humidity, wherein the compensation model is... Where C is the carbon dioxide compensation value, and C1 is the collected carbon dioxide concentration. For the preset reference temperature, The preset baseline humidity is T, and the ambient temperature is T. For the collected ambient humidity, This is the temperature compensation coefficient. This is the humidity compensation coefficient.

[0010] Furthermore, the analysis unit is also used to adjust the preset time based on the ratio of the carbon dioxide compensation value to the preset value if the average rate of decrease of the carbon dioxide compensation value within a preset time is greater than or equal to the preset rate of decrease and the carbon dioxide compensation value is greater than the preset value when the monitoring status is unqualified. Specifically, if the average rate of decrease of the carbon dioxide compensation value within the preset time is less than the preset rate of decrease or the carbon dioxide compensation value is greater than the preset value, the monitoring status is determined to be unqualified.

[0011] Furthermore, the analysis unit is also used to increase a preset duration based on the ratio of the carbon dioxide compensation value to the preset value, and the increase in the preset duration is proportional to the ratio.

[0012] Furthermore, the acquisition unit also includes a sensor correction module, which is used to correct the sensor calibration cycle determined by a gas concentration curve plotted based on a preset standard carbon dioxide concentration. The analysis unit is also used to repeatedly adjust the preset time at least once if the monitoring status is unqualified after adjusting the preset time, until the number of adjustments is less than the preset number and the monitoring status is qualified, or the number of adjustments is equal to the preset number, at which point the adjustment stops. The analysis unit is also used to calculate the average of the absolute values ​​of multiple compensation residuals based on the carbon dioxide compensation values ​​acquired at multiple historical times and the carbon dioxide concentration collected at the corresponding times if the monitoring status is unqualified after the adjustment stops. The analysis unit is also used to start the sensor correction module if the average value is greater than the preset average value, and adjust the calibration cycle based on the difference between the average value and the preset average value.

[0013] Furthermore, the analysis unit is also used to reduce the calibration cycle based on the difference between the average value and the preset average value, and the reduction in the calibration cycle is proportional to the difference.

[0014] Furthermore, the analysis unit is also used to calculate a first correlation coefficient between the compensation residual sequence and the temperature sequence, and a second correlation coefficient between the compensation residual sequence and the temperature sequence, based on the carbon dioxide compensation values ​​acquired at multiple historical times, the carbon dioxide concentration collected at the corresponding times, and the ambient temperature and humidity at the corresponding times, when the monitoring status is unqualified after adjusting the calibration cycle; the analysis unit is also used to correct the situation using the compensation coefficient adjustment module in the edge computing unit when the absolute value of the first correlation coefficient is greater than a first preset threshold, or when the absolute value of the second correlation coefficient is greater than a second preset threshold, wherein both the first preset threshold and the second preset threshold are greater than zero.

[0015] Furthermore, the compensation coefficient adjustment module is used to adjust the temperature compensation coefficient based on the ratio of the absolute value of the first correlation coefficient to the first preset threshold; the compensation coefficient adjustment module is also used to adjust the humidity compensation coefficient based on the ratio of the absolute value of the second correlation coefficient to the second preset threshold.

[0016] Furthermore, the compensation coefficient adjustment module is further configured to: increase the temperature compensation coefficient based on the ratio of the first correlation coefficient to the first preset threshold when the first correlation coefficient is greater than zero and greater than the first preset threshold, wherein the increase in the temperature compensation coefficient is proportional to the ratio; decrease the temperature compensation coefficient based on the ratio of the absolute value of the first correlation coefficient to the first preset threshold when the first correlation coefficient is less than zero and the absolute value of the first correlation coefficient is greater than the first preset threshold, wherein the decrease in the temperature compensation coefficient is proportional to the ratio; increase the humidity compensation coefficient based on the ratio of the second correlation coefficient to the second preset threshold when the second correlation coefficient is greater than zero and greater than the second preset threshold, wherein the increase in the humidity compensation coefficient is proportional to the ratio; and decrease the humidity compensation coefficient based on the ratio of the absolute value of the second correlation coefficient to the second preset threshold when the second correlation coefficient is less than zero and the absolute value of the second correlation coefficient is greater than the second preset threshold, wherein the decrease in the humidity compensation coefficient is proportional to the ratio.

[0017] Compared with existing technologies, the advantages of this invention are as follows: This invention collects carbon dioxide concentration and ambient temperature and humidity data based on carbon dioxide and temperature / humidity sensors, and performs periodic calibration on the sensors; it also uses a transmission mode switching module for data transmission, resulting in more accurate and complete data transmission; and it performs compensation calculations on the carbon dioxide concentration data using ambient temperature and humidity data, making the obtained carbon dioxide concentration more accurate. This allows for more accurate determination of whether carbon dioxide concentration needs adjustment based on the carbon dioxide compensation value or the rate of increase of the carbon dioxide compensation value; and it determines whether the monitoring status is qualified based on the average rate of decrease of the carbon dioxide compensation value within a preset time after adjustment is initiated and the carbon dioxide compensation value at the end of the preset time, and adjusts relevant parameters based on the monitoring status. This invention improves the efficiency of carbon dioxide monitoring.

[0018] Furthermore, the present invention automatically determines the transmission mode based on the transmission signal strength and transmission time delay through the transmission mode switching module, which can transmit information more timely and accurately by automatically switching the transmission mode, thereby further improving the monitoring efficiency of carbon dioxide.

[0019] Furthermore, the present invention uses a compensation model to correct the carbon dioxide concentration based at least on a preset reference temperature and a preset reference humidity, which makes the obtained carbon dioxide concentration more accurate, thereby making subsequent adjustments based on the obtained carbon dioxide concentration more effective, and further improving the monitoring efficiency of carbon dioxide.

[0020] Furthermore, the present invention adjusts the preset duration based on the ratio of the carbon dioxide compensation value to the preset value, which can more effectively monitor the monitoring status after the adjustment measures are initiated, thereby further improving the monitoring efficiency of carbon dioxide.

[0021] Furthermore, this invention determines the cause of unqualified monitoring status based on carbon dioxide compensation values ​​at multiple historical moments and the carbon dioxide concentration collected at the corresponding moments. This can more effectively determine whether the unqualified monitoring status is caused by sensor drift, thereby enabling more effective adjustments in the future and further improving the efficiency of carbon dioxide monitoring.

[0022] Furthermore, the present invention adjusts the calibration cycle of the sensor based on the difference between the average value and the preset average value. This allows for a more effective adjustment of the sensor's calibration cycle, resulting in more accurate carbon dioxide concentration measurements and further improving the efficiency of carbon dioxide monitoring.

[0023] Furthermore, the present invention determines the cause of the monitoring status failure based on the relationship between the absolute value of the first correlation coefficient and the first preset threshold, or the relationship between the absolute value of the second correlation coefficient and the second preset threshold, thereby enabling more effective subsequent adjustments and further improving the monitoring efficiency of carbon dioxide.

[0024] Furthermore, the present invention adjusts the temperature compensation coefficient based on the ratio of the first correlation coefficient to the first preset threshold, and adjusts the humidity compensation coefficient based on the ratio of the second correlation coefficient to the second preset threshold, thereby enabling more accurate calculation of carbon dioxide compensation values ​​and further improving the monitoring efficiency of carbon dioxide. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the Internet of Things-based real-time carbon dioxide monitoring system according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the steps of the real-time carbon dioxide monitoring method based on the Internet of Things according to an embodiment of the present invention. Figure 3 This is a flowchart illustrating the steps of determining the carbon dioxide compensation value based on the average rate of decrease within a preset time period and the carbon dioxide compensation value at the end of the preset time period, according to an embodiment of the present invention. Figure 4 This is a flowchart illustrating the steps of determining the monitoring status based on the preset time duration in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0027] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0028] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] Please see Figure 1 As shown, it is a schematic diagram of the structure of the real-time carbon dioxide monitoring system based on the Internet of Things according to an embodiment of the present invention.

[0030] The system includes an acquisition unit, an edge processing unit, a detection unit, and an analysis unit.

[0031] The acquisition unit includes a carbon dioxide sensor for collecting carbon dioxide concentration data, a temperature and humidity sensor for collecting ambient temperature and humidity data, and a calibration module for periodically calibrating the carbon dioxide sensor and the temperature and humidity sensor based on a gas concentration curve plotted according to a preset standard carbon dioxide concentration. The edge processing unit is connected to the acquisition unit and includes a transmission mode switching module for transmitting data collected by the acquisition unit, and a calculation module for performing compensation calculation on the carbon dioxide concentration data based on the ambient temperature and humidity data to obtain a carbon dioxide compensation value. The detection unit is connected to the edge processing unit and is used to determine whether to adjust the carbon dioxide concentration based on the carbon dioxide compensation value and a preset safety threshold, or the rate of increase of the carbon dioxide compensation value within a preset time. The analysis unit is connected to the detection unit. It is used to determine whether the monitoring status is qualified based on the average rate of decrease of the carbon dioxide compensation value within a preset time after the adjustment measures are initiated and the carbon dioxide compensation value at the end of the preset time. It also adjusts the preset time based on the monitoring status and adjusts the parameters in the calculation module based on the monitoring status after the preset time is adjusted.

[0032] Specifically, in this embodiment, the carbon dioxide sensor is an infrared absorption sensor with a detection range of 0-5000 ppm and a response time of less than or equal to 10 seconds. An integrated optical filter reduces the influence of interfering gases and improves detection specificity. The temperature and humidity sensor is an SHT30 sensor with a temperature accuracy of ±0.3℃ and a humidity accuracy of ±2% RH. The collected data is used for temperature and humidity compensation of CO2 concentration, offsetting the influence of environmental factors on the detection results.

[0033] Specifically, based on a preset standard CO2 concentration curve (three calibration points: 0ppm, 1000ppm, and 5000ppm), the sensor self-calibration is periodically triggered. During the calibration process, reference gas is introduced through an internal pump to automatically correct detection deviations and solve the sensor drift problem.

[0034] Please see Figure 2 The diagram shown is a flowchart of the steps of the real-time carbon dioxide monitoring method based on the Internet of Things according to an embodiment of the present invention.

[0035] The steps involved in real-time carbon dioxide monitoring based on the Internet of Things include: S1, acquire carbon dioxide concentration data and ambient temperature and humidity data by acquiring carbon dioxide sensor and temperature and humidity sensor in the acquisition unit, and periodically calibrate carbon dioxide sensor and temperature and humidity sensor by plotting gas concentration curve based on preset standard carbon dioxide concentration. S2, the data collected by the acquisition unit is transmitted through the transmission mode switching module in the edge processing unit connected to the acquisition unit, and the calculation module performs compensation calculation on the carbon dioxide concentration data based on the ambient temperature and humidity data to obtain the carbon dioxide compensation value. S3, the detection unit connected to the edge processing unit determines whether to adjust based on the carbon dioxide compensation value and a preset safety threshold, or the rate of increase of the carbon dioxide compensation value within a preset time, in order to reduce the carbon dioxide concentration; S4, the analysis unit connected to the detection unit determines whether the monitoring status is qualified based on the average rate of decrease of the carbon dioxide compensation value within a preset time after the adjustment measures are initiated and the carbon dioxide compensation value at the end of the preset time. The preset time is adjusted based on the monitoring status, and the parameters in the calculation module are adjusted based on the monitoring status after the preset time is adjusted.

[0036] Please see Figure 3 The flowchart shown is a step-by-step diagram of the steps for determining the carbon dioxide compensation value based on the average rate of decrease of the carbon dioxide compensation value within a preset time period and the carbon dioxide compensation value at the end of the preset time period, according to an embodiment of the present invention.

[0037] Specifically, based on the physical response limit of the electrochemical carbon dioxide sensor and the long-term operational stability of the core module, and combined with the stringent fault tolerance requirements for early warning accuracy in high-risk environments, the system also deeply fits the massive historical concentration fluctuations, equipment drift, and false alarm event data accumulated through statistical analysis during long-term network observation. Based on this, the system sets the numerical values ​​of subsequent preset or critical parameters.

[0038] Specifically, in this embodiment, taking a residential indoor environment as an example, the preset value L0 = 1000 ppm and the preset descent rate P0 = 50 ppm / minute, the comparison process between the average descent rate P based on the carbon dioxide compensation value and the preset descent rate P, and between the carbon dioxide compensation value L and the preset value L0, is as follows: If the average rate of decrease P of the carbon dioxide compensation value is less than the preset rate of decrease P, or the carbon dioxide compensation value L is greater than the preset value L0, the monitoring status is determined to be unqualified. If the average rate of decrease of the carbon dioxide compensation value P is greater than or equal to the preset rate of decrease P and the carbon dioxide compensation value L is less than or equal to the preset value L0, the monitoring status is determined to be qualified.

[0039] Specifically, if the monitoring status is unqualified, and the average rate of decrease of the carbon dioxide compensation value within the preset time period is greater than or equal to the preset rate of decrease, and the carbon dioxide compensation value is greater than the preset value, it indicates that the preset adjustment time of the system is too short, and ventilation is stopped before the concentration drops below the safety line. The preset time period is then adjusted based on the ratio of the carbon dioxide compensation value to the preset value. The preset ratio of the carbon dioxide compensation value to the preset value is Q0 = 1.5. The comparison process between the ratio Q of the carbon dioxide compensation value to the preset value and the preset ratio Q0 is as follows: If the ratio Q of the carbon dioxide compensation value to the preset value is less than or equal to the preset ratio Q0, the preset duration will be adjusted to 1.3 times the original preset duration, where the adjusted preset duration will be rounded up. If the ratio Q of the carbon dioxide compensation value to the preset value is greater than the preset ratio Q0, the preset duration will be adjusted to 2.1 times the original preset duration, where the adjusted preset duration will be rounded up.

[0040] Please see Figure 4 The diagram shown is a flowchart illustrating the steps of determining the monitoring status based on the preset time duration in an embodiment of the present invention.

[0041] Specifically, if the monitoring status is unqualified after adjusting the preset duration, the preset duration is adjusted at least once until the number of adjustments is less than the preset number and the monitoring status is qualified, or the number of adjustments is equal to the preset number, at which point the adjustment stops. If the monitoring status is unqualified after stopping the adjustment, the average value of the absolute values ​​of multiple compensation residuals is calculated based on the carbon dioxide compensation values ​​at multiple historical moments and the carbon dioxide concentration collected at the corresponding moments. If the average value is greater than the preset average value, it indicates that the sensor has experienced systematic drift, making the compensation model unable to be effectively corrected. In this case, the sensor correction module is activated, and the calibration cycle is adjusted based on the difference between the average value and the preset average value. The compensation residual is the difference between the carbon dioxide compensation value and the carbon dioxide concentration at the corresponding historical moment.

[0042] Specifically, if the average of the absolute values ​​of multiple compensated residuals has a preset difference R0 = 5ppm compared to the preset average, then the comparison process based on the difference R between the average and the preset average and the preset difference R0 is as follows: If the difference R between the average value and the preset average value is less than or equal to the preset difference R0, the calibration period will be adjusted to 0.9 times the original calibration period, where the adjusted calibration period will be rounded up. If the difference R between the average value and the preset average value is greater than the preset difference R0, the calibration period will be adjusted to 0.76 times the original calibration period, where the adjusted calibration period is rounded up.

[0043] Specifically, if the monitoring status is unqualified after adjusting the calibration cycle, based on the carbon dioxide compensation values ​​at multiple historical moments, the carbon dioxide concentration collected at the corresponding moment, and the ambient temperature and humidity at the corresponding moment, the first correlation coefficient between the compensation residual sequence and the temperature sequence, and the second correlation coefficient between the compensation residual sequence and the humidity sequence are calculated. If the absolute value of the first correlation coefficient is greater than the first preset threshold, or the absolute value of the second correlation coefficient is greater than the second preset threshold, it indicates that the compensation coefficient in the compensation model is not suitable. Then, the compensation coefficient adjustment module in the edge computing unit is used for correction. The first preset threshold and the second preset threshold are both greater than zero.

[0044] Specifically, the compensation coefficient adjustment module is used to adjust the temperature compensation coefficient based on the ratio of the absolute value of the first correlation coefficient to the first preset threshold; the compensation coefficient adjustment module is also used to adjust the humidity compensation coefficient based on the ratio of the absolute value of the second correlation coefficient to the second preset threshold.

[0045] Specifically, if the absolute value of the first correlation coefficient is equal to the preset ratio T0 of the first preset threshold, then the comparison process based on the ratio T of the absolute value of the first correlation coefficient to the first preset threshold and the preset ratio T0 is as follows: When the first correlation coefficient is greater than zero, If the ratio T of the first correlation coefficient to the first preset threshold is less than or equal to the preset ratio T0, the temperature compensation coefficient is adjusted to 1.2 times the original temperature compensation coefficient, wherein the adjusted temperature compensation coefficient is retained to one decimal place. If the ratio T of the first correlation coefficient to the first preset threshold is greater than the preset ratio T0, the temperature compensation coefficient is adjusted to 1.7 times the original temperature compensation coefficient, wherein the adjusted temperature compensation coefficient retains one decimal place.

[0046] When the first correlation coefficient is less than zero, If the ratio T of the absolute value of the first correlation coefficient to the first preset threshold is less than or equal to the preset ratio T0, the temperature compensation coefficient is adjusted to 0.9 times the original temperature compensation coefficient, wherein the adjusted temperature compensation coefficient retains one decimal place. If the ratio T of the absolute value of the first correlation coefficient to the first preset threshold is greater than the preset ratio T0, the temperature compensation coefficient is adjusted to 0.76 times the original temperature compensation coefficient, wherein the adjusted temperature compensation coefficient is retained to one decimal place.

[0047] Specifically, if the absolute value of the second correlation coefficient is equal to the preset ratio U0 of the second preset threshold, then the comparison process based on the ratio U0 of the absolute value of the second correlation coefficient to the second preset threshold and the preset ratio U0 is as follows: When the second correlation coefficient is greater than zero, If the ratio U of the second correlation coefficient to the second preset threshold is less than or equal to the preset ratio U0, the humidity compensation coefficient is adjusted to 1.16 times the original humidity compensation coefficient, wherein the adjusted humidity compensation coefficient is retained to one decimal place. If the ratio U of the second correlation coefficient to the second preset threshold is greater than the preset ratio U0, the humidity compensation coefficient is adjusted to 1.62 times the original humidity compensation coefficient, wherein the adjusted humidity compensation coefficient is retained to one decimal place.

[0048] When the second correlation coefficient is less than zero, If the ratio U of the absolute value of the second correlation coefficient to the second preset threshold is less than or equal to the preset ratio U0, the humidity compensation coefficient is adjusted to 0.83 times the original humidity compensation coefficient, wherein the adjusted humidity compensation coefficient is retained to one decimal place. If the ratio U of the absolute value of the second correlation coefficient to the second preset threshold is greater than the preset ratio U0, the humidity compensation coefficient is adjusted to 0.69 times the original humidity compensation coefficient, wherein the adjusted temperature compensation coefficient is retained to one decimal place.

[0049] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A real-time carbon dioxide monitoring system based on the Internet of Things, characterized in that, include: The acquisition unit includes a carbon dioxide sensor for acquiring carbon dioxide concentration data, a temperature and humidity sensor for acquiring ambient temperature and humidity data, and a calibration module for periodically calibrating the carbon dioxide sensor and the temperature and humidity sensor based on a gas concentration curve plotted according to a preset standard carbon dioxide concentration. An edge processing unit includes a transmission mode switching module for transmitting data collected by the acquisition unit, and a calculation module for performing compensation calculations on the carbon dioxide concentration data based on the ambient temperature and humidity data to obtain a carbon dioxide compensation value. The detection unit is used to determine whether to reduce the carbon dioxide concentration based on the carbon dioxide compensation value and a preset safety threshold, or the rate of increase of the carbon dioxide compensation value within a preset time. The analysis unit is used to determine whether the monitoring status is qualified based on the average rate of decrease of the carbon dioxide compensation value within a preset time after the adjustment measures are initiated and the carbon dioxide compensation value at the end of the preset time. It also adjusts the preset time based on the monitoring status and adjusts the parameters in the calculation module based on the monitoring status after the preset time is adjusted.

2. The IoT-based real-time carbon dioxide monitoring system according to claim 1, characterized in that, The transmission mode switching module is also used to automatically determine the transmission mode based on the transmission signal strength and transmission time delay.

3. The IoT-based real-time carbon dioxide monitoring system according to claim 2, characterized in that, The calculation module is used to correct the carbon dioxide concentration using a compensation model, based at least on a preset reference temperature and a preset reference humidity. The compensation model is as follows: Where C is the carbon dioxide compensation value, and C1 is the collected carbon dioxide concentration. For the preset reference temperature, The preset baseline humidity is T, and the ambient temperature is T. For the collected ambient humidity, This is the temperature compensation coefficient. This is the humidity compensation coefficient.

4. The IoT-based real-time carbon dioxide monitoring system according to claim 3, characterized in that, The analysis unit is also used to adjust the preset time based on the ratio of the carbon dioxide compensation value to the preset value if the average rate of decrease of the carbon dioxide compensation value within a preset time period is greater than or equal to a preset rate of decrease and the carbon dioxide compensation value is greater than a preset value, in the event that the monitoring status is unqualified. If the average rate of decrease of the carbon dioxide compensation value within a preset time period is less than the preset rate of decrease or the carbon dioxide compensation value is greater than the preset value, the monitoring status is determined to be unqualified.

5. The IoT-based real-time carbon dioxide monitoring system according to claim 4, characterized in that, The analysis unit is also used to increase a preset duration based on the ratio of the carbon dioxide compensation value to the preset value, and the increase in the preset duration is proportional to the ratio.

6. The IoT-based real-time carbon dioxide monitoring system according to claim 5, characterized in that, The acquisition unit also includes a sensor correction module, which is used to correct the sensor calibration cycle determined by a gas concentration curve plotted based on a preset standard carbon dioxide concentration. The analysis unit is also used to repeatedly adjust the preset time at least once if the monitoring status is not qualified after adjusting the preset time, until the adjustment is stopped when the number of adjustments is less than the preset number and the monitoring status is qualified or the number of adjustments is equal to the preset number. The analysis unit is also used to calculate the average of the absolute values ​​of multiple compensation residuals based on the carbon dioxide compensation values ​​obtained at multiple historical times and the carbon dioxide concentration collected at the corresponding times when the monitoring status is unqualified after the adjustment is stopped. The analysis unit is also used to activate the sensor correction module when the average value is greater than the preset average value, and to adjust the calibration cycle based on the difference between the average value and the preset average value.

7. The IoT-based real-time carbon dioxide monitoring system according to claim 6, characterized in that, The analysis unit is also used to reduce the calibration cycle based on the difference between the average value and the preset average value, and the reduction in the calibration cycle is proportional to the difference.

8. The IoT-based real-time carbon dioxide monitoring system according to claim 7, characterized in that, The analysis unit is also used to calculate, based on the carbon dioxide compensation values ​​at multiple historical moments, the carbon dioxide concentration collected at the corresponding moment, and the ambient temperature and humidity at the corresponding moment, a first correlation coefficient between the compensation residual sequence and the temperature sequence, and a second correlation coefficient between the compensation residual sequence and the temperature sequence, when the monitoring status is unqualified after the calibration cycle is adjusted. The analysis unit is further configured to correct for the following conditions using the compensation coefficient adjustment module in the edge computing unit: if the absolute value of the first correlation coefficient is greater than a first preset threshold, or if the absolute value of the second correlation coefficient is greater than a second preset threshold. Both the first preset threshold and the second preset threshold are greater than zero.

9. The IoT-based real-time carbon dioxide monitoring system according to claim 8, characterized in that, The compensation coefficient adjustment module is used to adjust the temperature compensation coefficient based on the ratio of the absolute value of the first correlation coefficient to the first preset threshold. The compensation coefficient adjustment module is also used to adjust the humidity compensation coefficient based on the ratio of the absolute value of the second correlation coefficient to the second preset threshold.

10. The IoT-based real-time carbon dioxide monitoring system according to claim 9, characterized in that, The compensation coefficient adjustment module is further configured to increase the temperature compensation coefficient based on the ratio of the first correlation coefficient to the first preset threshold when the first correlation coefficient is greater than zero and greater than the first preset threshold, and the increase in the temperature compensation coefficient is proportional to the ratio. The compensation coefficient adjustment module is further used to reduce the temperature compensation coefficient based on the ratio of the absolute value of the first correlation coefficient to the first preset threshold when the first correlation coefficient is less than zero and the absolute value of the first correlation coefficient is greater than the first preset threshold, and the reduction of the temperature compensation coefficient is proportional to the ratio. The compensation coefficient adjustment module is also used to increase the humidity compensation coefficient based on the ratio of the second correlation coefficient to the second preset threshold when the second correlation coefficient is greater than zero and greater than the second preset threshold, and the increase in the humidity compensation coefficient is proportional to the ratio. The compensation coefficient adjustment module is further used to reduce the humidity compensation coefficient based on the ratio of the absolute value of the second correlation coefficient to the second preset threshold when the second correlation coefficient is less than zero and the absolute value of the second correlation coefficient is greater than the second preset threshold, and the reduction of the humidity compensation coefficient is proportional to the ratio.

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