Refrigerant leakage detection method, device, system, equipment and storage medium

Abstract

The application discloses a refrigerant leakage detection method, device, system, equipment and storage medium. The method comprises the following steps: acquiring the real-time liquid storage amount of the liquid accumulator of an air conditioning system, and judging the detection state of the air conditioning system according to the real-time liquid storage amount; wherein the detection state comprises a first detectable state or an undetectable state; when the air conditioning system is in the first detectable state and the air conditioning system is in a first stable state, acquiring the expansion valve opening degree detection data set, and determining the leakage state of the refrigerant based on the expansion valve opening degree detection data set; or when the air conditioning system is in the undetectable state, adjusting the air conditioning system to a second detectable state, and when the air conditioning system is in a second stable state, acquiring the temperature detection data set, and determining the leakage state of the refrigerant based on the temperature detection data set. The embodiments of the application realize online remote detection of the leakage state of the refrigerant for any air conditioning system.

Description

Technical Field

[0001] This application belongs to the field of air conditioning and refrigeration technology, and in particular relates to a method, device, system, equipment and storage medium for detecting refrigerant leaks. Background Technology

[0002] Refrigerant leakage is a common malfunction in refrigeration and air conditioning systems. This malfunction not only leads to a decline in the performance of the air conditioning system but also causes air pollution. Multi-split systems typically have complex and long refrigerant piping, making them more susceptible to leakage. Currently, refrigerant leak detection for multi-split systems is usually performed annually: professional maintenance engineers control the unit to specific operating conditions, measure specific parameters, and compare the measured values ​​with thresholds to determine if a refrigerant leak has occurred. However, such periodic inspections cannot detect and prevent refrigerant leaks in a timely manner, and the operation is costly and negatively impacts the customer's air conditioning experience. Summary of the Invention

[0003] This application aims to at least partially address one of the technical problems in the related art. Therefore, one objective of this application is to provide a method, apparatus, system, device, and storage medium for detecting refrigerant leaks.

[0004] To address the aforementioned technical problems, embodiments of this application provide the following technical solutions:

[0005] A method for detecting refrigerant leaks, comprising:

[0006] The real-time liquid level in the receiver of the air conditioning system is obtained, and the detection status of the air conditioning system is determined based on the real-time liquid level; wherein, the detection status includes a first detectable status or an undetectable status;

[0007] When the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, the expansion valve opening detection dataset is acquired, and the refrigerant leakage state is determined based on the expansion valve opening detection dataset.

[0008] Alternatively, if the air conditioning system is in the undetectable state, the air conditioning system is adjusted to the second detectable state, and when the air conditioning system is in the second stable state, a temperature detection dataset is acquired, and the refrigerant leakage status is determined based on the temperature detection dataset.

[0009] Optionally, obtaining the real-time liquid level in the receiver of the air conditioning system and determining the detection status of the air conditioning system based on the real-time liquid level includes:

[0010] The configuration parameters of the air conditioning system are obtained, and the first liquid storage capacity of the condenser, the second liquid storage capacity of the evaporator, and the third liquid storage capacity of the liquid pipe are calculated based on the configuration parameters; wherein, the liquid storage includes the condenser, the evaporator, and the liquid pipe;

[0011] The sum of the first, second, and third liquid storage volumes is compared with the preset filling volume.

[0012] If the sum of the first, second, and third liquid storage volumes is greater than or equal to the preset filling volume, then the air conditioning system is determined to be in the first detectable state; or

[0013] If the sum of the first liquid storage volume, the second liquid storage volume, and the third liquid storage volume is less than the preset filling volume, then the air conditioning system is determined to be in the undetectable state.

[0014] Optionally, before acquiring the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, the method further includes:

[0015] The first real-time speed of the compressor of the air conditioning system is monitored, and multiple first abrupt change points of the first real-time speed are obtained;

[0016] Obtain multiple first real-time rotational speeds between every two adjacent first mutation points;

[0017] The first coefficient of variation is calculated based on multiple first real-time rotational speeds;

[0018] Compare the first coefficient of variation with the coefficient of variation threshold;

[0019] If the first coefficient of variation is less than the coefficient of variation threshold, then the air conditioning system is determined to be in the first stable state.

[0020] Optionally, when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, acquiring the expansion valve opening detection dataset includes:

[0021] The system acquires a first real-time operation dataset and a set of expansion valve opening measurement values ​​for the air conditioning system; wherein the first real-time operation dataset includes multiple first real-time operation parameters; and the set of expansion valve opening measurement values ​​includes a first expansion valve opening measurement value, a second expansion valve opening measurement value, and a third expansion valve opening measurement value.

[0022] Based on the first prediction model, the first real-time running dataset is calculated to obtain a set of predicted expansion valve opening values; wherein, the set of predicted expansion valve opening values ​​includes a first predicted expansion valve opening value, a second predicted expansion valve opening value, and a third predicted expansion valve opening value; wherein, the expansion opening detection dataset includes a set of measured expansion opening values ​​and a set of predicted expansion opening values.

[0023] Optionally, determining the refrigerant leakage state based on the expansion valve opening detection dataset includes:

[0024] A first deviation is obtained based on the first expansion valve opening measurement value and the first expansion valve opening prediction value; a second deviation is obtained based on the second expansion valve opening measurement value and the second expansion valve opening prediction value; and a third deviation is obtained based on the third expansion valve opening measurement value and the third expansion valve opening prediction value.

[0025] The target deviation is determined based on the first deviation, the second deviation, and the third deviation.

[0026] The target deviation is compared with a first determined threshold, and if the target deviation is greater than the first determined threshold, the air conditioning system is determined to be in a first leakage state.

[0027] Optionally, when the air conditioning system is in the undetectable state, adjusting the air conditioning system to the second detectable state includes:

[0028] When the air conditioning system is in the undetectable state, N sensors are installed in the gas-liquid separator of the air conditioning system to adjust the air conditioning system to the second detectable state; wherein, the multiple sensors are installed in different position ranges of the gas-liquid separator, and N is a positive integer.

[0029] Optionally, when the air conditioning system is in a second stable state, a temperature detection dataset is acquired, including:

[0030] When N=3, the second real-time operation dataset and temperature measurement value set of the air conditioning system are obtained; wherein, the second real-time operation dataset includes multiple second real-time operation data, and the temperature measurement value set includes a first temperature measurement value, a second temperature measurement value and a third temperature measurement value, and the first temperature measurement value is obtained based on a first sensor, the second temperature measurement value is obtained based on a second sensor, and the third temperature measurement value is obtained based on a third sensor;

[0031] Based on the second prediction model, the second real-time running dataset is calculated to obtain a temperature prediction set; wherein, the temperature prediction set includes a first temperature prediction value, a second temperature prediction value, and a third temperature prediction value; the temperature detection dataset includes a temperature measurement set and a temperature prediction set.

[0032] Optionally, determining the refrigerant leakage status based on the temperature detection dataset includes:

[0033] Based on the first predicted temperature value and the first measured temperature value, a first difference is calculated; based on the second predicted temperature value and the second measured temperature value, a second difference is calculated; based on the third predicted temperature value and the third measured temperature value, a third difference is calculated.

[0034] The target difference is calculated based on the first difference, the second difference, and the third difference.

[0035] The target difference is compared with a second determined threshold. If the target difference is greater than the second determined threshold, the air conditioning system is determined to be in a second leakage state.

[0036] Embodiments of this application also provide a refrigerant leak detection device, comprising:

[0037] The judgment module is used to obtain the real-time liquid storage volume of the liquid receiver of the air conditioning system, and to judge the detection status of the air conditioning system based on the real-time liquid storage volume; wherein, the detection status includes a first detectable status or an undetectable status.

[0038] The first determining module is used to acquire an expansion valve opening detection dataset and determine the refrigerant leakage state based on the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state.

[0039] The second determining module is used to adjust the air conditioning system to a second detectable state when the air conditioning system is in the undetectable state, and to acquire a temperature detection dataset when the air conditioning system is in a second stable state, and to determine the refrigerant leakage state based on the temperature detection dataset.

[0040] Embodiments of this application also provide an air conditioning system, including:

[0041] A liquid receiver, comprising a condenser, an evaporator, and a liquid pipe, is used to determine the detection status of the air conditioning system based on a first liquid storage volume in the condenser, a second liquid storage volume in the evaporator, and a third liquid storage volume in the liquid pipe; wherein the detection status includes a first detection status or an undetectable status;

[0042] A gas-liquid separator is connected to the evaporator; if the air conditioning system is in the undetectable state, the gas-liquid separator is further equipped with N sensors; where N is a positive integer.

[0043] Embodiments of this application also provide an electronic device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the method described above.

[0044] Embodiments of this application also provide a computer-readable storage medium, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the method described above.

[0045] The embodiments of this application have the following technical effects:

[0046] The above-mentioned technical solution of this application realizes a method for detecting the leakage state of different refrigerants matched with different air conditioning systems, which has strong versatility and wide application range. In addition, the embodiments of this application, after determining that the current air conditioning system is in a stable operating state, obtain stable and effective real-time operating data, and determine the leakage state of the refrigerant of the current air conditioning system based on the real-time and effective real-time operating data, which does not affect the operation of the unit and can accurately judge the fault in real time.

[0047] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of an air conditioning system provided in an embodiment of this application;

[0049] Figure 2 This is a schematic flowchart of a refrigerant leak detection method provided in an embodiment of this application;

[0050] Figure 3 This is a schematic diagram of the structure of a refrigerant leak detection device provided in an embodiment of this application. Detailed Implementation

[0051] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0052] To facilitate understanding of the embodiments by those skilled in the art, some terms are explained below:

[0053] Pettitt method: A nonparametric test method similar to the MK method.

[0054] like Figure 1 As shown, embodiments of this application also provide an air conditioning system, including:

[0055] A liquid receiver, comprising a condenser, an evaporator, and a liquid pipe, is used to determine the detection status of the air conditioning system based on a first liquid storage volume in the condenser, a second liquid storage volume in the evaporator, and a third liquid storage volume in the liquid pipe; wherein the detection status includes a first detection status or an undetectable status;

[0056] A gas-liquid separator is connected to the evaporator; if the air conditioning system is in the undetectable state, the gas-liquid separator is further equipped with N sensors; where N is a positive integer.

[0057] An optional embodiment of this application, such as... Figure 1 As shown, the air conditioning system also includes a compressor, a first expansion valve (EXVA), a second expansion valve (EXVi), and a third expansion valve (EXVC);

[0058] Specifically, the second end of the compressor is connected to the first end of the condenser, the second end of the condenser is connected to the first end of the first expansion valve (EXVA), the second end of the first expansion valve (EXVA) is connected to the first end of the liquid line, the second end of the liquid line is connected to the first ends of the second expansion valve (EXVi) and the third expansion valve (EXVC) respectively; the second end of the second expansion valve (EXVi) is connected to the first end of the evaporator, and the second end of the third expansion valve (EXVC) is connected to the first end of the gas-liquid separator.

[0059] The second end of the evaporator is connected to the second end of the gas-liquid separator, and the third end of the gas-liquid separator is connected to the second end of the compressor.

[0060] In an optional embodiment of this application, the air conditioning system is equipped with a built-in sensor or electrical signal to detect refrigerant leakage. That is, when the air conditioning system is in a first detectable state, the refrigerant leakage is detected based on the built-in sensor or electrical signal. However, when the air conditioning system is in an undetectable state, that is, the refrigerant leakage can no longer be detected based on the built-in sensor or electrical signal, in order to continue to detect the refrigerant leakage, this embodiment of the application installs multiple temperature sensors on the gas-liquid separator to obtain temperature detection data based on the sensors and determine the refrigerant leakage state.

[0061] In an optional embodiment of this application, when N=3, that is, the gas-liquid separator is equipped with a total of 3 sensors, namely a first sensor, a second sensor, and a third sensor; wherein, according to actual needs, the first sensor can be installed on the outer wall surface at the bottom of the gas-liquid separator; the second sensor can be installed on the outer wall surface in the middle of the gas-liquid separator; and the third sensor can be installed on the outer wall surface at the top of the gas-liquid separator; wherein, the first sensor is used to obtain a first temperature measurement value, the second sensor is used to obtain a second temperature measurement value, and the third sensor is used to obtain a third temperature measurement value.

[0062] like Figure 2 As shown, embodiments of this application provide a refrigerant leak detection method, applicable to, for example... Figure 1 The air conditioning system shown includes:

[0063] Step S21: Obtain the real-time liquid level in the receiver of the air conditioning system, and determine the detection status of the air conditioning system based on the real-time liquid level; wherein, the detection status includes a first detectable status or an undetectable status;

[0064] In an optional embodiment of this application, obtaining the real-time liquid level in the receiver of the air conditioning system and determining the detection status of the air conditioning system based on the real-time liquid level includes:

[0065] The configuration parameters of the air conditioning system are obtained, and the first liquid storage capacity of the condenser, the second liquid storage capacity of the evaporator, and the third liquid storage capacity of the liquid pipe are calculated based on the configuration parameters; wherein, the liquid storage includes the condenser, the evaporator, and the liquid pipe;

[0066] The sum of the first, second, and third liquid storage volumes is compared with the preset filling volume.

[0067] If the sum of the first, second, and third liquid storage volumes is greater than or equal to the preset filling volume, then the air conditioning system is determined to be in the first detectable state; or

[0068] If the sum of the first liquid storage volume, the second liquid storage volume, and the third liquid storage volume is less than the preset filling volume, then the air conditioning system is determined to be in the undetectable state.

[0069] In the embodiments of this application, in order to enable any air conditioning system to remotely and accurately determine the refrigerant leakage status online based on the real-time operating data of the air conditioning system, the detection status of the air conditioning system is first determined before determining the refrigerant leakage status, in order to determine whether the current status of the air conditioning system is suitable for determining the refrigerant leakage status.

[0070] Specifically, the configuration parameters of the air conditioning system are obtained; these parameters include the highest operating speed of the compressor and the corresponding set status parameters of the air conditioning system; these set status parameters include the set high pressure value, the set low pressure value, and the set superheat value, etc.

[0071] Then, based on the above configuration parameters of the air conditioning system, the first liquid storage capacity m of the condenser is calculated. cond The second liquid storage capacity m_evap of the evaporator and the third liquid storage capacity m_HL of the liquid pipe; wherein, the embodiments of this application assume that the refrigerant in the liquid pipe is pure liquid;

[0072] Obtain the first liquid storage volume m of the condenser cond The sum of the second liquid storage volume m_evap in the evaporator and the third liquid storage volume m_HL in the liquid pipe: m cond +m_evap+m_HL;

[0073] The preset filling amount M is not specifically limited in the embodiments of this application;

[0074] Furthermore, when (m cond +m_evap+m_HL) max If the value is ≥M, then it can be determined that the current air conditioning system cannot detect the refrigerant leakage status based on its built-in sensors or electrical signals, meaning that the current air conditioning system is in an undetectable state.

[0075] In an optional embodiment of this application, the determination of the detection status of the air conditioning system can also be based on the internal volume ratio of the gas-liquid separator to the evaporator.

[0076] Specifically, the content product ratio threshold can be preset according to actual needs, for example: [2, 3];

[0077] The content area ratio is compared with the content area ratio threshold. If the content area ratio exceeds the content area ratio threshold, it indicates that the current air conditioning system is in an undetectable state. Therefore, multiple temperature sensors need to be installed on the gas-liquid separator to adjust the current air conditioning system from an undetectable state to a second detectable state.

[0078] Step S22: When the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, acquire the expansion valve opening detection dataset, and determine the refrigerant leakage state based on the expansion valve opening detection dataset;

[0079] An optional embodiment of this application further includes, before acquiring the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state:

[0080] The first real-time speed of the compressor of the air conditioning system is monitored, and multiple first abrupt change points of the first real-time speed are obtained;

[0081] Obtain multiple first real-time rotational speeds between every two adjacent first mutation points;

[0082] The first coefficient of variation is calculated based on multiple first real-time rotational speeds;

[0083] Compare the first coefficient of variation with the coefficient of variation threshold;

[0084] If the first coefficient of variation is less than the coefficient of variation threshold, then the air conditioning system is determined to be in the first stable state.

[0085] In the embodiments of this application, before determining the refrigerant leakage status, it is first necessary to ensure that the data used to determine the leakage status is valid data, that is, the current air conditioning system is in a stable operating state.

[0086] Specifically, once it is determined that the current air conditioning system is in the first detection state, it is necessary to determine whether the current air conditioning system is operating stably. If the current air conditioning system is operating stably, the expansion valve opening detection data set can be obtained directly. Conversely, if the current air conditioning system is not operating stably, the operating status of the air conditioning system needs to be monitored until the air conditioning system is operating stably.

[0087] Furthermore, the first real-time speed of the compressor in the air conditioning system is monitored, and multiple first mutation points of the first real-time speed are obtained based on the Pettitt method; multiple first real-time speeds are set between every two first mutation points, and the coefficient of variation (COV) is calculated based on the multiple first real-time speeds between these two adjacent first mutation points.

[0088] COV = STD / MEAN;

[0089] Where STD is the standard deviation of multiple first real-time speeds between two adjacent first mutation points; MEAN is the average of multiple first real-time speeds between two identical adjacent first mutation points.

[0090] The coefficient of variation threshold δ is preset according to actual needs; however, the embodiments of this application do not specifically limit δ.

[0091] When COV < δ, it can be determined that the current air conditioning system is operating stably, and the expansion valve opening detection dataset can be obtained.

[0092] In an optional embodiment of this application, a first mutation point is obtained according to the time sequence. Then, the next first mutation point is determined based on the Pettitt method, and the corresponding COV is calculated based on the two adjacent first mutation points. The above steps are repeated until COV < δ.

[0093] In an optional embodiment of this application, the determination of whether the current air conditioning system is in a stable operating state can also be based on the unit root test method (ADF); wherein, the unit root test method (ADF) is used to determine whether a unit root exists in the sequence; if the sequence is stable or stationary, there is no unit root; if the sequence is unstable or non-stationary, there is a unit root.

[0094] Specifically, the null hypothesis (H0) of the unit root test (ADF) is that a unit root exists. If the obtained significance test statistic is less than three confidence levels (10%, 5%, 1%), then there is (90%, 95%, 99%) confidence to reject the null hypothesis (that a unit root exists), meaning that the current air conditioning system is in a stable operating state and the first real-time operating data can be obtained.

[0095] In an optional embodiment of this application, when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, acquiring the expansion valve opening detection dataset includes:

[0096] The system acquires a first real-time operation dataset and a set of expansion valve opening measurement values ​​for the air conditioning system; wherein the first real-time operation dataset includes multiple first real-time operation parameters; and the set of expansion valve opening measurement values ​​includes a first expansion valve opening measurement value, a second expansion valve opening measurement value, and a third expansion valve opening measurement value.

[0097] Based on the first prediction model, the first real-time running dataset is calculated to obtain a set of predicted expansion valve opening values; wherein, the set of predicted expansion valve opening values ​​includes a first predicted expansion valve opening value, a second predicted expansion valve opening value, and a third predicted expansion valve opening value; wherein, the expansion opening detection dataset includes a set of measured expansion opening values ​​and a set of predicted expansion opening values.

[0098] In the embodiments of this application, after determining that the air conditioning system is in a first stable state, a set of expansion valve opening measurement values ​​can be obtained based on measurements. Specifically, the first expansion valve opening measurement value corresponding to the first expansion valve, the second expansion valve opening measurement value corresponding to the second expansion valve, and the third expansion valve opening measurement value corresponding to the third expansion valve can be obtained based on existing measurement methods. The embodiments of this application do not impose specific limitations on this.

[0099] In an optional embodiment of this application, the predicted value set of expansion valve opening can be obtained based on a preset first prediction model and the obtained first real-time running dataset.

[0100] Specifically, in the embodiments of this application, the first prediction model can be based on any of the following implementations: multivariate linear regression equation, neural network model, random forest model, etc. The embodiments of this application do not impose specific limitations.

[0101] Furthermore, after obtaining the first real-time running dataset, the first real-time running dataset can be input into the first prediction model, and the predicted values ​​of the first expansion valve opening, the second expansion valve opening, and the third expansion valve opening can be output. For the first prediction model, a historical running dataset can be obtained before inputting the first real-time running dataset into the first prediction model, and the historical running dataset can be input into the first initial prediction model for multiple training sessions to finally obtain the first prediction model. In order to improve the accuracy of the output value of the first prediction model, in the early stage of the operation of the first prediction model, the first prediction model can be calibrated or corrected based on the real-time running data, and then the predicted values ​​of the first expansion valve opening, the second expansion valve opening, and the third expansion valve opening can be output respectively.

[0102] The predicted value of the first expansion valve opening / the predicted value of the second expansion valve opening / the predicted value of the third expansion valve opening can be calculated based on the following formula;

[0103] First expansion valve opening prediction value / Second expansion valve opening prediction value / Third expansion valve opening prediction value =

[0104] f(CompSPD,ODF,IDFs,Peco,Pe,Pc,T4,T5,T6B,T7C1);

[0105] Wherein, CompSPD is the real-time speed of the compressor; ODF is the speed of the indoor fan; IDFs is the speed of each indoor fan; Peco is the intermediate pressure of the compressor; Pe is the suction pressure of the compressor; Pc is the discharge pressure of the compressor; T4 is the outdoor temperature; T5 is the temperature before the indoor expansion valve; T6B is the outlet temperature of the economizer auxiliary side; and T7C1 is the discharge temperature of the compressor.

[0106] In an optional embodiment of this application, determining the refrigerant leakage state based on the expansion valve opening detection dataset includes:

[0107] A first deviation is obtained based on the first expansion valve opening measurement value and the first expansion valve opening prediction value; a second deviation is obtained based on the second expansion valve opening measurement value and the second expansion valve opening prediction value; and a third deviation is obtained based on the third expansion valve opening measurement value and the third expansion valve opening prediction value.

[0108] The target deviation is determined based on the first deviation, the second deviation, and the third deviation.

[0109] The target deviation is compared with a first determined threshold, and if the target deviation is greater than the first determined threshold, the air conditioning system is determined to be in a first leakage state.

[0110] In an embodiment of this application, a first expansion valve opening prediction value, a second expansion valve opening prediction value, and a third expansion valve opening prediction value are output based on a first prediction model. Based on the above algorithm, the first expansion valve opening measurement value, the second expansion valve opening measurement value, and the third expansion valve opening measurement value are obtained by measurement. Then, the corresponding items are subtracted to obtain multiple deviations, and the absolute value of each deviation is calculated. The three absolute values ​​are weighted to obtain the average deviation, which is the target deviation. The target deviation is compared with a first determined threshold to obtain the comparison result. Based on the comparison result, the refrigerant leakage status of the current air conditioning system is determined.

[0111] Specifically, the predicted value of the first expansion valve opening is subtracted from the measured value of the first expansion valve opening to obtain the first deviation, and then the absolute value α of the first deviation is obtained.

[0112] The difference between the predicted value of the second expansion valve opening and the measured value of the second expansion valve opening is used to obtain the second deviation, and then the absolute value β of the second deviation is obtained.

[0113] The difference between the predicted value of the third expansion valve opening and the measured value of the third expansion valve opening is used to obtain the third deviation, and then the absolute value of the third deviation χ is obtained.

[0114] Wherein, the weighting coefficient for the absolute value α of the first deviation is a; the weighting coefficient for the absolute value β of the second deviation is b; and the weighting coefficient for the absolute value χ of the third deviation is c.

[0115] Then the target deviation A=(a*α+b*β+c*χ) / 3;

[0116] Compare A with a first predetermined threshold γ; where 0 ≤ γ ≤ 0.1;

[0117] When A > γ, it can be determined that a refrigerant leak has occurred, that is, the refrigerant is in the first leakage state.

[0118] Conversely, if A ≤ γ, then it can be determined that no refrigerant leak has occurred.

[0119] Step S23: If the air conditioning system is in the undetectable state, adjust the air conditioning system to the second detectable state. When the air conditioning system is in the second stable state, acquire the temperature detection dataset and determine the refrigerant leakage state based on the temperature detection dataset.

[0120] In an optional embodiment of this application, adjusting the air conditioning system to a second detectable state when the air conditioning system is in the undetectable state includes:

[0121] When the air conditioning system is in the undetectable state, N sensors are installed in the gas-liquid separator of the air conditioning system to adjust the air conditioning system to the second detectable state; wherein, the multiple sensors are installed in different position ranges of the gas-liquid separator, and N is a positive integer.

[0122] In an optional embodiment of this application, in order to enable any air conditioning system to remotely determine whether a refrigerant leak has occurred online based on real-time operating data, it is necessary to first determine whether the current air conditioning system can detect the refrigerant leak before detecting the refrigerant leak status. If the current air conditioning system can detect the refrigerant leak status, then proceed to the next step; otherwise, the current air conditioning system needs to be adjusted to enable the detection of the refrigerant leak status.

[0123] Furthermore, in the embodiments of this application, after determining that the current air conditioning system cannot remotely detect the refrigerant leakage status online, multiple sensors are installed on the gas-liquid separator, and the real-time operating data of the air conditioning system is obtained through the sensors; this changes the previous data acquisition method of obtaining real-time operating data based on the air conditioning system's built-in sensors or electrical signals, and enables any air conditioning system to detect the refrigerant leakage status based on real-time operating data.

[0124] Furthermore, to ensure the validity of the real-time operating data obtained from the installed sensors, N sensors are installed at different locations within the gas-liquid separator.

[0125] In an optional embodiment of this application, before the air conditioning system reaches the second stable state, it is necessary to determine the operating state of the air conditioning system to determine whether the air conditioning system is in a stable operating state and to determine the validity of the obtained second real-time operating data.

[0126] Specifically, the second real-time speed of the compressor in the air conditioning system is monitored, and multiple second mutation points of the second real-time speed are obtained; multiple second real-time speeds between every two adjacent second mutation points are obtained; based on the multiple second real-time speeds, a second coefficient of variation is calculated; the second coefficient of variation is compared with a coefficient of variation threshold; if the second coefficient of variation is less than the coefficient of variation threshold, the air conditioning system is determined to be in a second stable state.

[0127] Furthermore, the calculation method for the second coefficient of variation is the same as that for the first coefficient of variation, and will not be repeated in the embodiments of this application.

[0128] In an optional embodiment of this application, when the air conditioning system is in a second stable state, acquiring a temperature detection dataset includes:

[0129] When N=3, the second real-time operation dataset and temperature measurement value set of the air conditioning system are obtained; wherein, the second real-time operation dataset includes multiple second real-time operation data, and the temperature measurement value set includes a first temperature measurement value, a second temperature measurement value and a third temperature measurement value, and the first temperature measurement value is obtained based on a first sensor, the second temperature measurement value is obtained based on a second sensor, and the third temperature measurement value is obtained based on a third sensor;

[0130] Based on the second prediction model, the second real-time running dataset is calculated to obtain a temperature prediction set; wherein, the temperature prediction set includes a first temperature prediction value, a second temperature prediction value, and a third temperature prediction value; the temperature detection dataset includes a temperature measurement set and a temperature prediction set.

[0131] In an embodiment of this application, three sensors are installed in the gas-liquid separator, including a first sensor, a second sensor, and a third sensor; wherein the first sensor, the second sensor, and the third sensor are all temperature sensors used to measure the real-time temperature;

[0132] Furthermore, when collecting temperature data, it is necessary to obtain the temperature data from the first sensor, the second sensor, and the third sensor respectively, and correspondingly obtain the first temperature measurement value, the second temperature measurement value, and the third temperature measurement value respectively.

[0133] The second real-time operating data of the air conditioning system is obtained and input into the second prediction model. The second prediction model processes the second real-time operating data and outputs the first temperature prediction value, the second temperature prediction value and the third temperature prediction value respectively.

[0134] Specifically, in the embodiments of this application, the second prediction model can be implemented based on any of the following: multivariate linear regression equation, neural network model, random forest model, etc. The embodiments of this application do not impose specific limitations. The training and debugging processes of the second prediction model are the same as those of the first prediction model, and the embodiments of this application will not elaborate on them further.

[0135] Furthermore, the first temperature prediction value / the second temperature prediction value / the third temperature prediction value can be calculated based on the following formula;

[0136] First temperature prediction / Second temperature prediction / Third temperature prediction =

[0137] f(CompSPD,ODF,IDFs,EXVAc,EXVic,EXVCc,Peco,Pe,Pc,T4,T5,T6B,T7C1);

[0138] Wherein, EXVAc is the measured opening value of the first expansion valve; EXVic is the measured opening value of the second expansion valve; and EXVCc is the measured opening value of the third expansion valve.

[0139] In an optional embodiment of this application, determining the refrigerant leakage state based on the temperature detection dataset includes:

[0140] Based on the first predicted temperature value and the first measured temperature value, a first difference is calculated; based on the second predicted temperature value and the second measured temperature value, a second difference is calculated; based on the third predicted temperature value and the third measured temperature value, a third difference is calculated.

[0141] The target difference is calculated based on the first difference, the second difference, and the third difference.

[0142] The target difference is compared with a second determined threshold. If the target difference is greater than the second determined threshold, the air conditioning system is determined to be in a second leakage state.

[0143] In an embodiment of this application, a first temperature prediction value, a second temperature prediction value, and a third temperature prediction value are output based on a second prediction model. Based on the above algorithm, a first temperature measurement value, a second temperature measurement value, and a third temperature measurement value are obtained. Then, the corresponding items are subtracted to obtain multiple difference values, and the absolute value of each difference value is calculated. The three absolute values ​​are weighted and averaged to obtain the target difference value. The target difference value is then compared with a second determined threshold to obtain the comparison result. Based on the comparison result, the refrigerant leakage status of the current air conditioning system is determined.

[0144] Specifically, the first predicted temperature value is subtracted from the first measured temperature value to obtain the first difference value, and then the absolute value of the first difference value is obtained.

[0145] The second temperature prediction value is subtracted from the second temperature measurement value to obtain the second difference value, and then the absolute value θ of the second difference value is obtained.

[0146] The difference between the predicted third temperature value and the measured third temperature value is obtained to get the third difference value, and then the absolute value ρ of the third difference value is obtained.

[0147] Among them, the absolute value of the first difference The weighting coefficient for the first difference is i; the weighting coefficient for the absolute value θ of the second difference is j; and the weighting coefficient for the absolute value ρ of the third difference is k.

[0148] Then the target difference A = (i*α + j*β + k*χ) / 3;

[0149] Compare A with the first predetermined threshold ζ; where 0 ≤ ζ ≤ 0.1;

[0150] When A > ζ, it can be determined that the refrigerant has leaked, that is, the refrigerant is in the second leakage state.

[0151] Conversely, if A ≤ ζ, then it can be determined that no refrigerant leak has occurred.

[0152] The embodiments of this application realize a method for detecting the leakage state of different refrigerants for different air conditioning systems, which has strong versatility and wide application range. In addition, the embodiments of this application, after determining that the current air conditioning system is in a stable operating state, obtain stable and effective real-time operating data, and determine the leakage state of the current air conditioning system's refrigerant based on the real-time and effective operating data, which does not affect the operation of the unit and can accurately judge the fault in real time.

[0153] like Figure 3 As shown, embodiments of this application also provide a refrigerant leak detection device 30, comprising:

[0154] The judgment module 31 is used to obtain the real-time liquid storage volume of the liquid receiver of the air conditioning system, and to judge the detection status of the air conditioning system based on the real-time liquid storage volume; wherein, the detection status includes a first detectable status or an undetectable status.

[0155] The first determining module 32 is used to acquire an expansion valve opening detection dataset and determine the refrigerant leakage state based on the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state.

[0156] The second determining module 33 is used to adjust the air conditioning system to a second detectable state when the air conditioning system is in the undetectable state, and to acquire a temperature detection dataset when the air conditioning system is in a second stable state, and to determine the refrigerant leakage state based on the temperature detection dataset.

[0157] Optionally, obtaining the real-time liquid level in the receiver of the air conditioning system and determining the detection status of the air conditioning system based on the real-time liquid level includes:

[0158] The configuration parameters of the air conditioning system are obtained, and the first liquid storage capacity of the condenser, the second liquid storage capacity of the evaporator, and the third liquid storage capacity of the liquid pipe are calculated based on the configuration parameters; wherein, the liquid storage includes the condenser, the evaporator, and the liquid pipe;

[0159] The sum of the first, second, and third liquid storage volumes is compared with the preset filling volume.

[0160] If the sum of the first, second, and third liquid storage volumes is greater than or equal to the preset filling volume, then the air conditioning system is determined to be in the first detectable state; or

[0161] If the sum of the first liquid storage volume, the second liquid storage volume, and the third liquid storage volume is less than the preset filling volume, then the air conditioning system is determined to be in the undetectable state.

[0162] Optionally, when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, acquiring the expansion valve opening detection dataset further includes:

[0163] The first real-time speed of the compressor of the air conditioning system is monitored, and multiple first abrupt change points of the first real-time speed are obtained;

[0164] Obtain multiple first real-time rotational speeds between every two adjacent first mutation points;

[0165] The first coefficient of variation is calculated based on multiple first real-time rotational speeds;

[0166] Compare the first coefficient of variation with the coefficient of variation threshold;

[0167] If the first coefficient of variation is less than the coefficient of variation threshold, then the air conditioning system is determined to be in the first stable state.

[0168] Optionally, when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, acquiring the expansion valve opening detection dataset includes:

[0169] The system acquires a first real-time operation dataset and a set of expansion valve opening measurement values ​​for the air conditioning system; wherein the first real-time operation dataset includes multiple first real-time operation parameters; and the set of expansion valve opening measurement values ​​includes a first expansion valve opening measurement value, a second expansion valve opening measurement value, and a third expansion valve opening measurement value.

[0170] Based on the first prediction model, the first real-time running dataset is calculated to obtain a set of predicted expansion valve opening values; wherein, the set of predicted expansion valve opening values ​​includes a first predicted expansion valve opening value, a second predicted expansion valve opening value, and a third predicted expansion valve opening value; wherein, the expansion opening detection dataset includes a set of measured expansion opening values ​​and a set of predicted expansion opening values.

[0171] Optionally, determining the refrigerant leakage state based on the expansion valve opening detection dataset includes:

[0172] A first deviation is obtained based on the first expansion valve opening measurement value and the first expansion valve opening prediction value; a second deviation is obtained based on the second expansion valve opening measurement value and the second expansion valve opening prediction value; and a third deviation is obtained based on the third expansion valve opening measurement value and the third expansion valve opening prediction value.

[0173] The target deviation is determined based on the first deviation, the second deviation, and the third deviation.

[0174] The target deviation is compared with a first determined threshold, and if the target deviation is greater than the first determined threshold, the air conditioning system is determined to be in a first leakage state.

[0175] Optionally, when the air conditioning system is in the undetectable state, adjusting the air conditioning system to the second detectable state includes:

[0176] When the air conditioning system is in the undetectable state, N sensors are installed in the gas-liquid separator of the air conditioning system to adjust the air conditioning system to the second detectable state; wherein, the multiple sensors are installed in different position ranges of the gas-liquid separator, and N is a positive integer.

[0177] Optionally, when the air conditioning system is in a second stable state, a temperature detection dataset is acquired, including:

[0178] When N=3, the second real-time operation dataset and temperature measurement value set of the air conditioning system are obtained; wherein, the second real-time operation dataset includes multiple second real-time operation data, and the temperature measurement value set includes a first temperature measurement value, a second temperature measurement value and a third temperature measurement value, and the first temperature measurement value is obtained based on a first sensor, the second temperature measurement value is obtained based on a second sensor, and the third temperature measurement value is obtained based on a third sensor;

[0179] Based on the second prediction model, the second real-time running dataset is calculated to obtain a temperature prediction set; wherein, the temperature prediction set includes a first temperature prediction value, a second temperature prediction value, and a third temperature prediction value; the temperature detection dataset includes a temperature measurement set and a temperature prediction set.

[0180] Optionally, determining the refrigerant leakage status based on the temperature detection dataset includes:

[0181] Based on the first predicted temperature value and the first measured temperature value, a first difference is calculated; based on the second predicted temperature value and the second measured temperature value, a second difference is calculated; based on the third predicted temperature value and the third measured temperature value, a third difference is calculated.

[0182] The target difference is calculated based on the first difference, the second difference, and the third difference.

[0183] The target difference is compared with a second determined threshold. If the target difference is greater than the second determined threshold, the air conditioning system is determined to be in a second leakage state.

[0184] Embodiments of this application also provide an electronic device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the method described above.

[0185] Embodiments of this application also provide a computer-readable storage medium, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the method described above.

[0186] Furthermore, other configurations and functions of the apparatus in the embodiments of this application are known to those skilled in the art, and will not be described in detail here to reduce redundancy.

[0187] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0188] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0189] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0190] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0191] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0192] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0193] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0194] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for detecting refrigerant leaks, characterized in that, include: The real-time liquid level of the receiver in the air conditioning system is obtained, and the detection status of the air conditioning system is determined based on the real-time liquid level; wherein, the detection status includes a first detectable status or an undetectable status; When the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, the expansion valve opening detection dataset is acquired, and the refrigerant leakage state is determined based on the expansion valve opening detection dataset. Alternatively, if the air conditioning system is in the undetectable state, the air conditioning system is adjusted to the second detectable state, and when the air conditioning system is in the second stable state, a temperature detection dataset is acquired, and the refrigerant leakage state is determined based on the temperature detection dataset. The step of obtaining the real-time liquid level in the receiver of the air conditioning system and determining the detection status of the air conditioning system based on the real-time liquid level includes: The configuration parameters of the air conditioning system are obtained, and the first liquid storage capacity of the condenser, the second liquid storage capacity of the evaporator, and the third liquid storage capacity of the liquid pipe are calculated based on the configuration parameters; wherein, the liquid storage includes the condenser, the evaporator, and the liquid pipe; The sum of the first, second, and third liquid storage volumes is compared with the preset filling volume. If the sum of the first, second, and third liquid storage volumes is greater than or equal to the preset filling volume, then the air conditioning system is determined to be in the first detectable state; or If the sum of the first liquid storage volume, the second liquid storage volume, and the third liquid storage volume is less than the preset filling volume, then the air conditioning system is determined to be in the undetectable state. When the air conditioning system is in the undetectable state, adjusting the air conditioning system to the second detectable state includes: When the air conditioning system is in the undetectable state, N sensors are installed in the gas-liquid separator of the air conditioning system to adjust the air conditioning system to the second detectable state; wherein, the multiple sensors are respectively installed in different position ranges of the gas-liquid separator, and N is a positive integer; When the air conditioning system is in the second stable state, a temperature detection dataset is acquired, including: When N=3, the second real-time operation dataset and temperature measurement value set of the air conditioning system are obtained; wherein, the second real-time operation dataset includes multiple second real-time operation data, and the temperature measurement value set includes a first temperature measurement value, a second temperature measurement value and a third temperature measurement value, and the first temperature measurement value is obtained based on a first sensor, the second temperature measurement value is obtained based on a second sensor, and the third temperature measurement value is obtained based on a third sensor; Based on the second prediction model, the second real-time running dataset is calculated to obtain a set of predicted temperature values; wherein, the set of predicted temperature values ​​includes a first predicted temperature value, a second predicted temperature value, and a third predicted temperature value; the temperature detection dataset includes a set of measured temperature values ​​and a set of predicted temperature values.

2. The method according to claim 1, characterized in that, Before acquiring the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, the method further includes: The first real-time speed of the compressor of the air conditioning system is monitored, and multiple first abrupt change points of the first real-time speed are obtained; Obtain multiple first real-time rotational speeds between every two adjacent first mutation points; The first coefficient of variation is calculated based on multiple first real-time rotational speeds; Compare the first coefficient of variation with the coefficient of variation threshold; If the first coefficient of variation is less than the coefficient of variation threshold, then the air conditioning system is determined to be in the first stable state.

3. The method according to claim 1, characterized in that, When the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state, the acquisition of the expansion valve opening detection dataset includes: The system acquires a first real-time operation dataset and a set of expansion valve opening measurement values ​​for the air conditioning system; wherein, the first real-time operation dataset includes multiple first real-time operation data; and the set of expansion valve opening measurement values ​​includes a first expansion valve opening measurement value, a second expansion valve opening measurement value, and a third expansion valve opening measurement value. Based on the first prediction model, the first real-time running dataset is calculated to obtain a set of predicted expansion valve opening values; wherein, the set of predicted expansion valve opening values ​​includes a first predicted expansion valve opening value, a second predicted expansion valve opening value, and a third predicted expansion valve opening value; wherein, the expansion opening detection dataset includes a set of measured expansion opening values ​​and a set of predicted expansion opening values.

4. The method according to claim 3, characterized in that, The determination of the refrigerant leakage state based on the expansion valve opening detection dataset includes: A first deviation is obtained based on the first expansion valve opening measurement value and the first expansion valve opening prediction value; a second deviation is obtained based on the second expansion valve opening measurement value and the second expansion valve opening prediction value; and a third deviation is obtained based on the third expansion valve opening measurement value and the third expansion valve opening prediction value. The target deviation is determined based on the first deviation, the second deviation, and the third deviation. The target deviation is compared with a first determined threshold, and if the target deviation is greater than the first determined threshold, the air conditioning system is determined to be in a first leakage state.

5. The method according to claim 1, characterized in that, The determination of the refrigerant leakage status based on the temperature detection dataset includes: Based on the first predicted temperature value and the first measured temperature value, a first difference is calculated; based on the second predicted temperature value and the second measured temperature value, a second difference is calculated; based on the third predicted temperature value and the third measured temperature value, a third difference is calculated. The target difference is calculated based on the first difference, the second difference, and the third difference. The target difference is compared with a second determined threshold. If the target difference is greater than the second determined threshold, the air conditioning system is determined to be in a second leakage state.

6. A refrigerant leak detection device, characterized in that, The refrigerant leak detection device is used to implement the method as described in any one of claims 1 to 5, including: The judgment module is used to obtain the real-time liquid storage volume of the liquid receiver of the air conditioning system, and to judge the detection status of the air conditioning system based on the real-time liquid storage volume; wherein, the detection status includes a first detectable status or an undetectable status. The first determining module is used to acquire an expansion valve opening detection dataset and determine the refrigerant leakage state based on the expansion valve opening detection dataset when the air conditioning system is in the first detectable state and the air conditioning system is in the first stable state. The second determining module is used to adjust the air conditioning system to a second detectable state when the air conditioning system is in the undetectable state, and to acquire a temperature detection dataset when the air conditioning system is in a second stable state, and to determine the refrigerant leakage state based on the temperature detection dataset.

7. An air conditioning system, characterized in that, include: The refrigerant leak detection device as described in claim 6; A liquid receiver, comprising a condenser, an evaporator, and a liquid pipe, is used to determine the detection status of the air conditioning system based on a first liquid storage volume in the condenser, a second liquid storage volume in the evaporator, and a third liquid storage volume in the liquid pipe; wherein the detection status includes a first detection status or an undetectable status; A gas-liquid separator is connected to the evaporator; if the air conditioning system is in the undetectable state, the gas-liquid separator is further equipped with N sensors; where N is a positive integer.

8. An electronic device, characterized in that, The method includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor, when executing the computer program, implements the method as claimed in any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device on which the computer-readable storage medium is located to perform the method as described in any one of claims 1 to 5.

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