Method and system for identifying false detection according to time-dependent change of refrigerant concentration

Abstract

The invention provides a method for identifying false detection according to time-dependent change of refrigerant concentration, the method is applied to an air conditioning system, and the detection method comprises the following steps: determining whether the indoor refrigerant concentration exceeds a specified value or not through a refrigerant sensor; when the refrigerant concentration exceeds a specified value, an alarm is given, a safety device is started, and the change of the indoor refrigerant concentration is detected in real time; inputting the refrigerant concentration corresponding to each time into an error detection calculation model to calculate a fluctuation value of the leakage, and if the fluctuation value is greater than a standard fluctuation value, determining that the leakage belongs to error detection; if the fluctuation value is smaller than or equal to the standard fluctuation value, the leakage belongs to refrigerant leakage. The technical problem that the use experience of the air conditioner is seriously affected due to the fact that the refrigerant sensor may be affected by interfering substances in the detection process and the air conditioner is shut down due to false detection is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to a method and system for identifying misdetection based on temporal changes in refrigerant concentration. Background Art

[0002] In air conditioners, in order to prevent global warming, refrigerants with a small global warming potential (GWP) have begun to be used. However, most refrigerants with a small GWP are flammable, such as R32. In addition, in a multi-split system that uses one outdoor unit to control multiple indoor units, the risk of fire caused by refrigerant leakage increases due to the large amount of refrigerant filled. Therefore, in order to detect indoor refrigerant leakage as early as possible, a refrigerant sensor is used. The refrigerant sensor is installed as an external device inside the indoor unit of the air conditioner or indoors. In the case of an external refrigerant sensor, since the refrigerant is heavier than air, it is installed near the ground to quickly detect refrigerant leakage.

[0003] The problem is that the refrigerant sensor may be affected by interfering substances during the detection process, resulting in false detection and causing the air conditioner to shut down, seriously affecting the user experience of the air conditioner. Summary of the invention

[0004] The present invention solves the technical problem that the refrigerant sensor may be affected by interfering substances during the detection process, resulting in false detection and causing the air conditioner to shut down, which seriously affects the user experience of the air conditioner. The present invention detects the change of indoor refrigerant concentration in real time, and inputs the refrigerant concentration corresponding to each time into the false detection calculation model to calculate the fluctuation value of the leakage, thereby realizing the identification of false detection and effectively improving the user experience of the air conditioner.

[0005] To solve the above problems, the present invention provides a method for identifying false detections based on the time-dependent changes in refrigerant concentration, which is applied to air-conditioning systems. The detection method includes: determining whether the indoor refrigerant concentration exceeds a specified value through a refrigerant sensor; when the refrigerant concentration exceeds the specified value, sounding an alarm and activating a safety device, and detecting the changes in the indoor refrigerant concentration in real time; inputting the refrigerant concentration corresponding to each time into a false detection calculation model to calculate the fluctuation value of the leakage. If there is a fluctuation value greater than the standard fluctuation value, the leakage is a false detection; if there is a fluctuation value less than or equal to the standard fluctuation value, the leakage is a refrigerant leakage.

[0006] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by detecting the changes in indoor refrigerant concentration in real time and inputting the data into the false detection calculation model for analysis, it is possible to more accurately identify false detections and avoid false alarms caused by interfering substances. By calculating the fluctuation value of this leak and comparing it with the standard fluctuation value, it is possible to accurately determine whether it is a false detection or a real refrigerant leak, which helps to avoid misoperation of the system. Avoiding air conditioning shutdowns caused by false detections can improve the stability and reliability of the air conditioning system and enhance the user experience. Accurately identifying refrigerant leaks can avoid unnecessary maintenance and repair costs, save maintenance costs, and extend the service life of the air conditioning system.

[0007] Furthermore, the change of indoor refrigerant concentration is detected in real time, including: using a refrigerant sensor to detect and record the indoor refrigerant concentration in real time within a set time.

[0008] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: the sensor detects and records the indoor refrigerant concentration in real time, which can provide more accurate and continuous monitoring data compared with intermittent or threshold-based monitoring methods, and help to more accurately judge the refrigerant leakage. By detecting and recording the refrigerant concentration within the set time, the influence of interfering substances on the refrigerant sensor can be eliminated, and the recognition accuracy of the air conditioning system for false detection of refrigerant leakage can be increased.

[0009] Furthermore, the fluctuation value is based on the elapsed time t within the set time after the refrigerant concentration exceeds the specified value and the detected concentration corresponding to the elapsed time t. Sure.

[0010] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: the fluctuation value can reflect the actual fluctuation of the refrigerant concentration. Compared with the alarm mechanism of a single threshold, it can more accurately judge the change trend of the refrigerant concentration and reduce the occurrence of false detection. Determining the fluctuation value according to the elapsed time t within the set time and the corresponding detection concentration can increase the accuracy of the fluctuation value and improve the flexibility and adaptability of the system.

[0011] Furthermore, the fluctuation value is specifically determined by the following fluctuation value calculation formula: is the detection concentration; is the elapsed time; is the exponential function of the base e of the natural logarithm; A is a constant; B is a constant; Among them, constant A and constant B are determined by at least two groups of elapsed time t and the detected concentration corresponding to the elapsed time t. Calculated; the fluctuation value is the percentage change of constant A or constant B calculated at any two times.

[0012] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the fluctuation of refrigerant concentration can be monitored more accurately through the fluctuation value calculation formula, which improves the accuracy and reliability of monitoring. The fluctuation value is determined according to the percentage change value of constant A and constant B, and can be flexibly adjusted according to actual conditions, making the system more suitable for different environments and conditions. The fluctuation value calculation formula can improve the detection capability of the system, enable the system to more accurately judge and respond to the fluctuation of refrigerant concentration, and improve the stability of the system.

[0013] Furthermore, the standard fluctuation value is , the set time is thirty minutes; if the refrigerant concentration fluctuates within the set time of thirty minutes and the value is greater than the standard fluctuation value , then this leakage is a false detection.

[0014] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: by setting the standard of time and fluctuation value, it is possible to accurately judge whether the refrigerant concentration exceeds the specified value and continues to fluctuate, thereby reducing the false alarm rate and avoiding misjudgment of normal conditions. By setting the set time and standard fluctuation value, the accuracy of detection can be improved, ensuring that the alarm is triggered only when there is a real leak, reducing the occurrence of false alarms. In addition, the reliability of leakage judgment can be increased, making the judgment more objective and accurate, which helps to take timely countermeasures.

[0015] Furthermore, the fluctuation value calculation formula is determined based on the refrigerant leakage rate, the volume of the room, the ventilation volume of the room, the ventilation times and the detection concentration.

[0016] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by considering factors such as refrigerant leakage rate, room volume, ventilation volume, ventilation times and detection concentration, the fluctuation value calculation formula can more accurately determine the leakage situation and improve the accuracy of leakage detection. Based on comprehensive consideration of multiple factors, the fluctuation value calculation formula can establish a more reliable detection mechanism, reduce the false detection rate, and improve the stability and reliability of the system.

[0017] Furthermore, the fluctuation value calculation formula is derived through the following calculation formula: V is the volume of the room; Q is the ventilation volume of the room; is the number of ventilations; is the detection concentration; is the elapsed time; is the refrigerant leakage rate; in, from It gradually increases and eventually approaches ; .

[0018] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: the fluctuation value calculation formula can realize dynamic monitoring of refrigerant leakage, and the fluctuation value is calculated in real time to reflect the changing trend of leakage speed, making the monitoring more comprehensive and accurate. The derivation of the fluctuation value calculation formula takes into account factors such as room volume, ventilation volume, and ventilation frequency. Compared with traditional methods, the refrigerant leakage can be evaluated more accurately, and the detection accuracy is improved.

[0019] Furthermore, the air conditioning system uses a flammable refrigerant, and the specified value is one quarter of the lower limit flammable concentration of the flammable refrigerant.

[0020] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by taking one-quarter of the lower limit flammable concentration of the flammable refrigerant as the prescribed value, the sensitivity of the monitoring system to potential dangers can be improved, thereby more safely monitoring refrigerant leakage and reducing safety risks. By taking the prescribed value as the reference standard, the system can detect refrigerant leakage earlier, improve the effect of early warning, and help to take timely measures to avoid accidents. Taking one-quarter of the lower limit flammable concentration of the flammable refrigerant as the prescribed value helps the system comply with relevant safety standards and regulations, and improves the compliance and safety of the system.

[0021] Furthermore, the detection method includes: if the leakage is a false detection, cancelling the alarm processing start and cancelling the start of the safety device; if the leakage is a refrigerant leakage, sounding the alarm again.

[0022] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: by distinguishing between false detection and refrigerant leakage, the leakage type can be accurately determined, unnecessary alarms and safety device activation can be avoided, and the accuracy of detection can be improved. The processing method for canceling alarms and safety device activation is more intelligent, avoiding interference with normal operations and improving the intelligence of the system. In the case of refrigerant leakage, the system can issue an alarm again, so that the problem can be quickly detected and handled, improving the response speed of the system.

[0023] The present invention also provides an air-conditioning system that identifies false detections based on the temporal changes in refrigerant concentration. The air-conditioning system that identifies false detections based on the temporal changes in refrigerant concentration implements a method for identifying false detections based on the temporal changes in refrigerant concentration. The air-conditioning system includes a refrigerant sensor, an alarm, a safety device and a storage device; wherein the refrigerant sensor is connected to the storage device and is installed on a wall in a room; when the refrigerant concentration exceeds a specified value, the refrigerant concentration is written to the storage device; when the change in the indoor refrigerant concentration is detected in real time, the refrigerant concentration corresponding to each time is written to the storage device; when the false detection calculation model performs calculations, the false detection calculation model reads the refrigerant concentration corresponding to each time in the storage device.

[0024] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the air conditioning system can detect the change of indoor refrigerant concentration in real time, and write the refrigerant concentration data at each time point into the storage device, realizing the real-time monitoring and recording of the change of refrigerant concentration, which is helpful to find abnormal situations in time. By introducing the false detection calculation model, by reading the refrigerant concentration data corresponding to each time point in the storage device, the system can identify and calculate false detections, further improving the system's ability to handle false alarms. By monitoring and identifying the changes in refrigerant concentration over time, the system can more effectively ensure the safe operation of the air conditioning system, reduce the air conditioner stop caused by false detection, and improve the comfort of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flow chart of a method for identifying misdetection based on time-dependent changes in refrigerant concentration provided by an embodiment of the present invention; Figure 2 A graph showing changes in refrigerant concentration within a set time period provided by an embodiment of the present invention; Figure 3 A flow chart of system execution steps for identifying misdetection based on time-dependent changes in refrigerant concentration provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] See also Figures 1 to 3 This embodiment provides a method for identifying false detections based on the time-dependent change of refrigerant concentration, which is applied to an air conditioning system. The detection method includes: Through the refrigerant sensor, determine whether the indoor refrigerant concentration exceeds the specified value; when the refrigerant concentration exceeds the specified value, an alarm is issued and the safety device is activated, and the change of the indoor refrigerant concentration is detected in real time; the refrigerant concentration corresponding to each time is input into the false detection calculation model to calculate the fluctuation value of this leakage. If there is a fluctuation value greater than the standard fluctuation value, this leakage is a false detection; if there is a fluctuation value less than or equal to the standard fluctuation value, this leakage is a refrigerant leakage.

[0028] Specifically, in the present embodiment, the refrigerant sensor element includes a semiconductor type, an infrared type, a thermal conductivity type, etc. The refrigerant sensor element of the present embodiment can use any type of detection method as long as it has a component for false detection. For example, a semiconductor type refrigerant sensor exposes a heated semiconductor to the refrigerant gas, interacts with the semiconductor, and uses a change in the current passing through the semiconductor. The change in the current value is sent to the control unit as a refrigerant detection signal. However, it is known that in addition to the refrigerant, organic silicone compounds, for example, also interact with the semiconductor, and the current passing through the semiconductor changes. In addition, the infrared type used for the refrigerant sensor uses different absorption wavelengths of infrared light depending on the type of refrigerant. Ester compounds and the like also have absorption near the absorption wavelength of fluorine-based refrigerants, becoming interfering substances.

[0029] Specifically, this embodiment calculates the fluctuation value of the leakage through the false detection calculation model, and determines whether it is a false detection according to the size of the fluctuation value, because the influence of the interfering substance on the refrigerant sensor may cause the fluctuation value to be greater than the standard fluctuation value.

[0030] In one embodiment of the present application, real-time detection of changes in indoor refrigerant concentration includes: using a refrigerant sensor to detect and record the indoor refrigerant concentration in real time within a set time.

[0031] Specifically, in this embodiment, the set time can be thirty minutes, and the refrigerant sensor detects and records the change of the refrigerant concentration in the room in real time within thirty minutes. A representative example of false detection is the organic silicone gas contained in cosmetic spray, but spray products are not expected to be used continuously for more than 30 minutes, and the change within 30 minutes from the start of the leak detection can fully determine the false detection.

[0032] In one embodiment of the present application, the fluctuation value is based on the elapsed time t within a set time after the refrigerant concentration exceeds the specified value and the detected concentration corresponding to the elapsed time t. Sure.

[0033] Specifically, in this embodiment, the fluctuation value is determined by confirming that the time t has elapsed within 30 minutes from the leak detection and its corresponding detection concentration. The result is obtained through repeated calculations. The fluctuation value of normal refrigerant leakage will not exceed the standard fluctuation value within 30 minutes, while the fluctuation value caused by interfering substances will exceed the standard fluctuation value within 30 minutes.

[0034] In one embodiment of the present application, the fluctuation value is specifically determined by the following fluctuation value calculation formula: is the detection concentration; is the elapsed time; is an exponential function of the base e of the natural logarithm; A is a constant; B is a constant; wherein constant A and constant B are determined by at least two sets of elapsed time t and detected concentrations corresponding to elapsed time t. Calculated; the fluctuation value is the percentage change of constant A or constant B calculated at any two times.

[0035] Specifically, in this embodiment, the elapsed time is used and detection concentration relationship, , to determine whether the detected refrigerant leak is a refrigerant leak or a sudden gas release. and the detection concentration of the refrigerant sensor Start with a combination of 2 or more data The coefficients A and B are as follows. and the elapsed time When A or B of the repeatedly calculated values ​​corresponding to the detected concentration fluctuates by more than the standard fluctuation value, it is judged as a false detection. False detection means that the refrigerant sensor detects something other than refrigerant, for example, it means that the refrigerant sensor mistakenly detects temporary items such as cosmetic sprays and insecticides as refrigerant.

[0036] In one embodiment of the present application, the standard fluctuation value is , the set time is thirty minutes; if the refrigerant concentration fluctuates within the set time of thirty minutes and the value is greater than the standard fluctuation value , then this leakage is a false detection.

[0037] Specifically, in this embodiment, if A or B changes within 30 minutes from the time of leak detection, The above shows that the refrigerant sensor is affected by interfering substances, such as cosmetic sprays, pesticides, etc. These interfering substances will basically dissipate within 30 minutes, causing a significant change in the refrigerant concentration detected by the refrigerant sensor. Among them, the percentage change value refers to the value obtained by dividing the change between two values ​​by the original value and then multiplying it by 100, which is usually used to express the percentage of relative change.

[0038] In one embodiment of the present application, the fluctuation value calculation formula is determined based on the refrigerant leakage rate, the volume of the room, the ventilation volume of the room, the ventilation frequency and the detection concentration.

[0039] Specifically, in this embodiment, the change in refrigerant concentration when the indoor refrigerant leaks can be accurately calculated through fluid analysis. When the place where the refrigerant leaks is far enough from the ground, such as in a ceiling unit, there is no big difference even if the indoor concentration is considered uniform as shown below. The fluctuation value calculation formula derived from the refrigerant leakage rate, the volume of the room, the ventilation volume of the room, the ventilation frequency and the refrigerant concentration in the room has a more reliable detection efficiency and improves the stability of the air conditioning system.

[0040] In one embodiment of the present application, the fluctuation value calculation formula is derived by the following calculation formula: V is the volume of the room; Q is the ventilation volume of the room; is the number of ventilations; is the detection concentration; is the elapsed time; is the refrigerant leakage rate; in, from It gradually increases and eventually approaches ; .

[0041] Specifically, in this embodiment, the refrigerant leakage rate Maximum , ventilation times 0.5 to 10 times, the room volume Set as , set the ventilation frequency to 0.5 to 10 times, and calculate the time-dependent change of the refrigerant concentration, such as Figure 2 Here, R32 yes If the alarm setting value is set to ,but ,exist Figure 2 Even if the concentration exceeds the detection value , the refrigerant concentration will continue to rise, gradually approaching a certain value as when the ventilation frequency is 10 times ( .in, It is the lower limit flammable concentration of flammable refrigerant.

[0042] In one embodiment of the present application, the air conditioning system uses a flammable refrigerant, and the specified value is one quarter of the lower limit flammable concentration of the flammable refrigerant.

[0043] Specifically, the lower limit of the flammable refrigerant concentration refers to the lowest limit of the refrigerant concentration in the air. Below this concentration, the mixture of the refrigerant and the air will not burn or explode. The lower limit flammable concentration is , the prescribed value will be set to one-fourth of the lower limit of flammable concentration. In this way, even if the concentration slightly exceeds the prescribed value, measures can be taken in time to avoid potential safety risks. This practice can improve safety and protect personnel and equipment from potential dangers.

[0044] In one embodiment of the present application, the detection method includes: if the leakage is a false detection, canceling the alarm processing start and canceling the start of the safety device; if the leakage is a refrigerant leakage, issuing an alarm again.

[0045] Specifically, in this example, when the refrigerant concentration exceeds a specified value, such as LFL / 4, an alarm is sounded and an instruction to activate the safety device is issued. The alarm is built into the refrigerant sensor device, and there is no need to prepare an alarm device separately. The safety device is a safety shut-off valve and a fresh air device, a blower, etc. of the refrigeration cycle. Activating the alarm and safety device when the refrigerant concentration exceeds the specified value may be a false detection, and this is a crisis management measure to prevent safety from being compromised due to delayed action.

[0046] In one embodiment of the present application, a method for identifying false detections based on temporal changes in refrigerant concentration is implemented based on an air-conditioning system that identifies false detections based on temporal changes in refrigerant concentration, the air-conditioning system comprising a refrigerant sensor, an alarm, a safety device and a storage device; wherein the refrigerant sensor is connected to the storage device and is installed on a wall indoors; when the refrigerant concentration exceeds a specified value, the refrigerant concentration is written to the storage device; when the change in indoor refrigerant concentration is detected in real time, the refrigerant concentration corresponding to each time is written to the storage device; when the false detection calculation model performs calculations, the false detection calculation model reads the refrigerant concentration corresponding to each time in the storage device.

[0047] Specifically, in this embodiment, the refrigerant sensor is used in a ceiling unit or a wall-mounted unit, and the refrigerant sensor is installed on a wall in the room. The air conditioning system based on identifying misdetection based on time-varying refrigerant concentration of the present application includes the method for identifying misdetection based on time-varying refrigerant concentration of any technical solution of the present application, and therefore, it has all the beneficial effects of the method for identifying misdetection based on time-varying refrigerant concentration of any technical solution of the present application, which will not be repeated here.

[0048] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for identifying false detection based on the time-dependent change of refrigerant concentration, applied to an air conditioning system, characterized in that: The detection method comprises: Determining whether the indoor refrigerant concentration exceeds a specified value through the refrigerant sensor; When the refrigerant concentration exceeds the specified value, an alarm is sounded and a safety device is activated, and changes in the indoor refrigerant concentration are detected in real time; The refrigerant concentration corresponding to each time is input into the false detection calculation model to calculate the fluctuation value of this leakage. If the fluctuation value is greater than the standard fluctuation value, this leakage is a false detection; if the fluctuation value is less than or equal to the standard fluctuation value, this leakage is a refrigerant leakage.

2. The method for identifying misdetection based on temporal change of refrigerant concentration according to claim 1, characterized in that: The real-time detection of the change in the indoor refrigerant concentration includes: The refrigerant concentration in the room is detected and recorded in real time within a set time through the refrigerant sensor.

3. The method for identifying misdetection based on the temporal change of refrigerant concentration according to claim 2, characterized in that: The fluctuation value is based on the elapsed time t within the set time after the refrigerant concentration exceeds the specified value and the detected concentration corresponding to the elapsed time t Sure.

4. The method for identifying misdetection based on temporal change of refrigerant concentration according to claim 3, characterized in that: The fluctuation value is specifically determined by the following fluctuation value calculation formula: is the detection concentration; is the elapsed time; is the exponential function of the base e of the natural logarithm; A is a constant; B is a constant; Wherein, the constant A and the constant B are determined by at least any two groups of the elapsed time t and the detected concentration corresponding to the elapsed time t. Calculated; the fluctuation value is the percentage change value of constant A or constant B calculated at any two times.

5. The method for identifying misdetection based on the temporal change of refrigerant concentration according to claim 3, characterized in that: The standard fluctuation value is , the set time is thirty minutes; Among them, if the refrigerant concentration has a fluctuation value greater than the standard fluctuation value within the set time of thirty minutes , then this leakage is a false detection.

6. The method for identifying misdetection based on temporal change of refrigerant concentration according to claim 4, characterized in that: The fluctuation value calculation formula is determined based on the refrigerant leakage rate, the volume of the room, the ventilation volume of the room, the ventilation times and the detection concentration.

7. The method for identifying misdetection based on the temporal change of refrigerant concentration according to claim 6, characterized in that: The fluctuation value calculation formula is derived by the following calculation formula: V is the volume of the room; Q is the ventilation volume of the room; is the number of ventilations; is the detection concentration; is the elapsed time; is the refrigerant leakage rate; in, from It gradually increases and eventually approaches ; 。 8. The method for identifying misdetection based on temporal change of refrigerant concentration according to claim 1, characterized in that: The air conditioning system uses a flammable refrigerant, and the specified value is one quarter of the lower limit flammable concentration of the flammable refrigerant.

9. The method for identifying misdetection based on the temporal change of refrigerant concentration according to claim 1, characterized in that: The detection method comprises: If this leakage is a false detection, the alarm handling and safety device activation are canceled; if this leakage is a refrigerant leakage, the alarm is sounded again.

10. An air conditioning system for identifying false detections based on temporal changes in refrigerant concentration, characterized in that: The air conditioning system for identifying misdetection based on time-dependent changes in refrigerant concentration implements the method for identifying misdetection based on time-dependent changes in refrigerant concentration as described in any one of claims 1 to 9, wherein the air conditioning system includes a refrigerant sensor, an alarm, a safety device, and a storage device; Among them, the refrigerant sensor is connected to the storage device and installed on the indoor wall; when the refrigerant concentration exceeds the specified value, the refrigerant concentration is written into the storage device; when the change of the refrigerant concentration in the room is detected in real time, the refrigerant concentration corresponding to each time is written into the storage device; when the false detection calculation model performs calculation, the false detection calculation model reads the refrigerant concentration corresponding to each time in the storage device.

Images