Method for judging refrigerant leakage and air conditioning unit

Abstract

The application discloses a kind of refrigerant leakage judging method and air conditioning unit, the refrigerant leakage judging method includes: obtaining the historical condition parameter of the unit to be detected, and the historical characteristic parameter corresponding to the historical condition parameter one by one;The current condition parameter and current characteristic parameter of the unit to be detected are detected;The historical characteristic parameter corresponding to the historical condition parameter closest to current condition parameter is calculated, and the deviation rate of current characteristic parameter;According to the deviation rate, it is judged that the unit to be detected exists refrigerant leakage.Compared with the prior art, the current operating data and historical operating data of the unit to be detected can be combined to accurately judge whether the unit to be detected exists refrigerant leakage, and the unit to be detected can be processed in advance to avoid damage to the unit to be detected.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of refrigeration, and in particular to a refrigerant leakage judgment method and air conditioning unit. BACKGROUND

[0002] Currently, air conditioning units achieve refrigeration, heating and other functions through refrigerant circulation, so the sealing of the air conditioning unit is extremely important. When the air conditioning unit has refrigerant leakage, the performance of the air conditioning unit will deteriorate, and in severe cases, the unit will be damaged.

[0003] In existing air conditioning units, after refrigerant leakage, the air conditioning unit cannot accurately determine whether refrigerant leakage exists, and cannot timely handle the situation after refrigerant leakage. Until the situation is serious, the air conditioning unit is damaged.

[0004] Some schemes simply judge the pressure and temperature of the air conditioning unit, but are easily affected by the valve control of the air conditioning unit, with a high false positive rate.

[0005] Therefore, how to design a refrigerant leakage judgment method and air conditioning unit that can accurately determine whether the air conditioning unit has refrigerant leakage is a technical problem that needs to be solved in the industry. SUMMARY

[0006] In view of the problem in the prior art that simple judgment of the pressure and temperature of the air conditioning unit to determine whether refrigerant leakage exists is easily affected by the valve control, and the false positive rate of refrigerant leakage in the air conditioning unit is extremely high, the present application provides a refrigerant leakage judgment method and air conditioning unit.

[0007] The technical scheme of the present application is to provide a refrigerant leakage judgment method, comprising:

[0008] Obtain the historical condition parameters of the to-be-detected unit and the historical characteristic parameters corresponding one-to-one to the historical condition parameters;

[0009] Detect the current condition parameters and current characteristic parameters of the to-be-detected unit;

[0010] Calculate the deviation rate of the historical characteristic parameters corresponding to the historical condition parameters closest to the current condition parameters and the current characteristic parameters;

[0011] Determine whether the to-be-detected unit has refrigerant leakage according to the deviation rate.

[0012] Further, when calculating the deviation rate, it further comprises:

[0013] Determine whether the current condition parameters are equal to the historical condition parameters closest to them;

[0014] If yes, the deviation rate is calculated by the historical characteristic parameter corresponding to the historical condition parameter closest to the current condition parameter and the current characteristic parameter;

[0015] If no, the historical characteristic parameter corresponding to the historical condition parameter closest to the current condition parameter is modified, and the deviation rate is calculated by the current characteristic parameter and the modified historical characteristic parameter.

[0016] Further, the calculation model for modifying the historical characteristic parameter corresponding to the historical condition parameter closest to the current condition parameter is:

[0017] Pg2= Pg0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0)

[0018] Pd2= Pd0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1)

[0019] Tp2= Tp0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0)

[0020] Fn2= Fn0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1);

[0021] Wherein, Pg0, Pd0, Tp0, Fn0 are unmodified historical characteristic parameters, Pg2, Pd2, Tp2, Fn2 are modified historical characteristic parameters, Tw1, Tn1, Y1 are current condition parameters, Tw0, Tn0, Y0 are historical condition parameters closest to the current condition parameters.

[0022] Further, the calculation model for the deviation rate is:

[0023] Px=0.25*{(1- Pg1 / Pg2)+(1- Pd1 / Pd2)+(1- Tp1 / Tp2)+(1- Fn1 / Fn2)};

[0024] Or Px=0.25*{(1- Pg1 / Pg0)+(1- Pd1 / Pd0)+(1- Tp1 / Tp0)+(1- Fn1 / Fn0)};

[0025] Wherein, Px is the deviation rate, Pg0, Pd0, Tp0, Fn0 are unmodified historical characteristic parameters, Pg1, Pd1, Tp1, Fn1 are current characteristic parameters, Pg2, Pd2, Tp2, Fn2 are modified historical characteristic parameters.

[0026] Further, according to the deviation rate, it is judged that the to-be-detected unit is refrigerant leakage, comprising:

[0027] determining whether the deviation rate is greater than a first preset deviation rate;

[0028] If yes, it is determined that the to-be-detected unit exists refrigerant leakage.

[0029] If no, it is determined that the to-be-detected unit does not exist refrigerant leakage.

[0030] Further, when it is determined that the to-be-detected unit exists refrigerant leakage, the method further comprises:

[0031] calculating a deviation rate corresponding to a unit operating current in the current characteristic parameter;

[0032] determining whether the determination result of the refrigerant leakage is a false positive according to the deviation rate corresponding to the unit operating current.

[0033] Further, determining whether the determination result of the refrigerant leakage is a false positive according to the deviation rate corresponding to the unit operating current comprises:

[0034] determining whether the deviation rate corresponding to the unit operating current is greater than a first preset deviation rate;

[0035] If yes, adjusting the opening degree of the electronic expansion valve in the to-be-detected unit, and detecting whether the current condition parameter changes, and when the current condition parameter does not change, determining that it is a false positive, otherwise, determining that it is not a false positive;

[0036] If no, determining that it is a false positive.

[0037] Further, when it is determined that the determination result of the refrigerant leakage is not a false positive, the method further comprises:

[0038] determining whether the deviation rate is less than a second preset deviation rate;

[0039] If yes, performing frequency limiting processing on the compressor in the to-be-detected unit;

[0040] If no, performing shutdown processing on the to-be-detected unit.

[0041] Further, the condition parameters of the to-be-detected unit include an outdoor environment temperature, an indoor environment temperature, and a compressor frequency.

[0042] The characteristic parameters of the to-be-detected unit include a unit module high pressure, a unit module low pressure, a unit exhaust temperature, an opening degree of an electronic expansion valve, and a unit operating current.

[0043] The application further provides an air conditioning unit, which has a refrigerant leakage judgment module, and the refrigerant leakage judgment module performs the above refrigerant leakage judgment method.

[0044] Compared with the prior art, the present application has at least the following beneficial effects:

[0045] 1、The present application can combine current condition parameters, current characteristic parameters, historical condition parameters and historical characteristic parameters to accurately determine whether the air conditioning unit has refrigerant leakage, thereby avoiding the problem that the air conditioning unit cannot be detected when refrigerant leakage occurs, leading to damage to the air conditioning unit.

[0046] 2、The present application further determines whether it is a false determination when determining that the air conditioning unit has refrigerant leakage, thereby improving the accuracy of the present application in determining whether the air conditioning unit has refrigerant leakage.

[0047] 3、The present application gives corresponding solutions for different refrigerant leakage conditions, thereby avoiding the problem that the performance of the air conditioning unit is deteriorated due to refrigerant leakage. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0049] Figure 1 for the overall flowchart of the refrigerant leakage determination method of the present application;

[0050] Figure 2 for the selection process of parameters in the refrigerant leakage determination method of the present application;

[0051] Figure 3 for the determination process of whether the refrigerant has leakage in the refrigerant leakage determination method of the present application;

[0052] Figure 4 for the determination process of whether the determination result of the refrigerant leakage is a false determination in the refrigerant leakage determination method of the present application;

[0053] Figure 5 for the strategy executed when the refrigerant leakage is determined in the present application;

[0054] Figure 6 for the specific flowchart of the refrigerant leakage determination method of the present application. DETAILED DESCRIPTION

[0055] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and examples.

[0056] Therefore, one feature indicated in the specification will be used to illustrate one feature of one embodiment of the present application, rather than implying that each embodiment of the present application must have the illustrated feature. In addition, it should be noted that the specification describes many features. Although certain features can be combined together to show possible system designs, these features can also be used in other combinations that are not explicitly described. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0057] The principles and structures of the present application will be described in detail below in conjunction with the accompanying drawings and examples.

[0058] In existing air conditioning units, the air conditioning unit cannot accurately determine whether there is refrigerant leakage after refrigerant leakage, and cannot timely handle the situation after refrigerant leakage, until the situation is serious, resulting in damage to the air conditioning unit.

[0059] Some solutions simply judge the pressure and temperature of the air conditioning unit, but are easily affected by the valve control of the air conditioning unit, and have a high false positive rate.

[0060] The present application proposes a refrigerant leakage judgment method to solve the above problems, please refer to Figure 1 The refrigerant leakage judgment method provided by the present application comprises the following steps:

[0061] Obtain the historical condition parameters of the to-be-detected unit and the historical characteristic parameters corresponding to the historical condition parameters one by one;

[0062] Detect the current condition parameters and the current characteristic parameters of the to-be-detected unit;

[0063] Calculate the deviation rate of the historical characteristic parameters corresponding to the closest historical condition parameters of the current condition parameters from the current characteristic parameters;

[0064] Judge whether the to-be-detected unit has refrigerant leakage according to the deviation rate.

[0065] The judgment idea of the application is that when the air conditioning unit is running, each set of condition parameters corresponds to a set of characteristic parameters, if the air conditioning unit does not exist refrigerant leakage, the corresponding relationship between the condition parameters and the characteristic parameters is relatively stable, that is, under the same condition parameter, the obtained characteristic parameter is relatively close, and the deviation rate is relatively small, on the contrary, if there is refrigerant leakage, at this time, under the same condition parameter, the deviation rate of the obtained characteristic parameter is relatively large, the application determines whether there is refrigerant leakage by the deviation rate;

[0066] Based on the above idea, after detecting the current condition parameter of the to-be-detected unit, the closest historical condition parameter to the current condition parameter is obtained, in theory, the current characteristic parameter is close to the selected historical condition parameter at this time, the application calculates the deviation rate of the current characteristic parameter and the historical condition parameter, which can be used to determine whether the to-be-detected unit has refrigerant leakage problem.

[0067] That is, the application can accurately determine whether the air conditioning unit has refrigerant leakage by combining the current condition parameter, the current characteristic parameter, the historical condition parameter and the historical characteristic parameter, thereby avoiding the problem that the air conditioning unit cannot be detected when the refrigerant leaks, resulting in damage to the air conditioning unit.

[0068] When the application obtains the historical condition parameter and the historical characteristic parameter, a plurality of data are obtained, and then when the current condition parameter and the current characteristic parameter of the to-be-detected unit are detected, there are two cases, the first case is that the current condition parameter detected at present has a historical condition parameter consistent with it, at this time, the historical characteristic parameter corresponding to the historical condition parameter can be directly compared with the current characteristic parameter;

[0069] The second case is that the current condition parameter detected at present cannot find a completely corresponding historical condition parameter in the historical condition parameters obtained before, at this time, a calibration action is performed to obtain the closest historical condition parameter and historical characteristic parameter, the historical condition parameter is scaled to the current condition parameter, and then the historical characteristic parameter is scaled according to the same scaling ratio, at this time, the historical characteristic parameter can be used as a reference to calculate the above deviation rate;

[0070] Please refer to Figure 2 Based on the above two cases, when the application calculates the deviation rate, the following steps are included:

[0071] Determine whether the current condition parameter is equal to the closest historical condition parameter;

[0072] If yes, calculate the deviation rate of the historical characteristic parameter corresponding to the closest historical condition parameter of the current condition parameter and the current characteristic parameter;

[0073] If no, the historical characteristic parameter corresponding to the historical condition parameter closest to the current condition parameter is modified, and the deviation rate is calculated based on the current characteristic parameter and the modified historical characteristic parameter.

[0074] Here, when the determination is yes, it is the first case, and the current condition parameter is consistent with the historical condition parameter, so the historical characteristic parameter does not need to be modified, and the deviation rate can be directly calculated based on the historical characteristic parameter and the current characteristic parameter.

[0075] When the determination is no, it is the second case, and the historical characteristic parameter needs to be modified, and then the deviation rate is calculated based on the modified historical characteristic parameter and the current characteristic parameter.

[0076] That is, when the current condition parameter deviates from the historical condition parameter, the historical characteristic parameter can be modified to avoid misjudgment of the refrigerant leakage caused by calculation error, and the accuracy of the refrigerant leakage judgment is improved.

[0077] Further, the calculation model for modifying the historical characteristic parameter corresponding to the historical condition parameter closest to the current condition parameter in the present application is:

[0078] Pg2= Pg0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0)

[0079] Pd2= Pd0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1)

[0080] Tp2= Tp0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0)

[0081] Fn2= Fn0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1);

[0082] Wherein, Pg0, Pd0, Tp0, Fn0 are unmodified historical characteristic parameters, Pg2, Pd2, Tp2, Fn2 are modified historical characteristic parameters, Tw1, Tn1, Y1 are current condition parameters, Tw0, Tn0, Y0 are historical condition parameters closest to the current condition parameters.

[0083] Here, Pg0 is the unmodified high pressure of the machine module in the machine group to be detected, Pd0 is the unmodified low pressure of the machine module in the machine group to be detected, Tp0 is the unmodified exhaust temperature of the machine group to be detected, and Fn0 is the unmodified opening degree of the electronic expansion valve in the machine group to be detected.

[0084] Pg2 is the corrected high pressure of the unit module in the unit to be detected, Pd2 is the corrected low pressure of the unit module in the unit to be detected, Tp2 is the corrected exhaust temperature of the unit module in the unit to be detected, and Fn2 is the corrected opening degree of the electronic expansion valve in the unit to be detected;

[0085] Tw1 is the current outdoor environment temperature, Tn1 is the current indoor environment temperature, and Y1 is the current compressor frequency;

[0086] Tw0 is the historical outdoor environment temperature, Tn1 is the historical indoor environment temperature, and Y0 is the historical compressor frequency;

[0087] As can be seen from the above calculation model, when each historical characteristic parameter is corrected, the ratio of all current condition parameters and historical condition parameters is considered, so that the historical characteristic parameter after correction is the historical characteristic parameter corresponding to the original historical condition parameter and the historical characteristic parameter under the condition that the historical condition parameter is consistent with the current condition parameter;

[0088] That is, by using the above calculation model, the historical condition parameter can be corrected to be equal to the current condition parameter, the historical characteristic parameter is corrected to be the historical characteristic parameter corresponding to the historical condition parameter at this time, and the deviation rate is calculated by using the historical characteristic parameter at this time and the current characteristic parameter to determine whether the unit to be detected has refrigerant leakage, so that the correctness of the determination is higher.

[0089] Further, the calculation model of the deviation rate in the present application is:

[0090] Px=0.25*{(1- Pg1 / Pg2)+(1- Pd1 / Pd2)+(1- Tp1 / Tp2)+(1- Fn1 / Fn2)};

[0091] Or Px=0.25*{(1- Pg1 / Pg0)+(1- Pd1 / Pd0)+(1- Tp1 / Tp0)+(1- Fn1 / Fn0)};

[0092] Wherein, Px is the deviation rate, Pg0, Pd0, Tp0, Fn0 are the uncorrected historical characteristic parameters, Pg1, Pd1, Tp1, Fn1 are the current characteristic parameters, and Pg2, Pd2, Tp2, Fn2 are the corrected historical characteristic parameters.

[0093] Here, Pg0 is the uncorrected high pressure of the unit module in the unit to be detected, Pd0 is the uncorrected low pressure of the unit module in the unit to be detected, Tp0 is the uncorrected exhaust temperature of the unit module in the unit to be detected, and Fn0 is the uncorrected opening degree of the electronic expansion valve in the unit to be detected.

[0094] Pg1 is the current unit module high pressure in the unit to be detected, Pd1 is the current unit module low pressure in the unit to be detected, Tp1 is the current unit exhaust temperature in the unit to be detected, and Fn1 is the current electronic expansion valve opening degree in the unit to be detected;

[0095] Pg2 is the corrected unit module high pressure in the unit to be detected, Pd2 is the corrected unit module low pressure in the unit to be detected, Tp2 is the corrected unit exhaust temperature in the unit to be detected, and Fn2 is the corrected electronic expansion valve opening degree in the unit to be detected;

[0096] As can be seen from the above calculation model, the calculation model of the deviation rate in the application is also divided into two cases, in the first case, the current characteristic parameter and the corrected historical characteristic parameter are used for calculation, which is used for the case that the current condition parameter and the historical condition parameter are not consistent in the foregoing;

[0097] In the second case, the current characteristic parameter and the uncorrected historical characteristic parameter are used for calculation, which is used for the case that the current condition parameter and the historical condition parameter are consistent in the foregoing;

[0098] As can be seen from the calculation model of the above two cases, the deviation rate of the application is actually the mean of multiple characteristic parameters, that is, the application uses the above calculation model to consider all the characteristic parameters, and the finally obtained deviation rate data is more effective.

[0099] Please refer to Figure 3 In the application, whether the unit to be detected has refrigerant leakage is judged according to the deviation rate, which comprises:

[0100] Whether the deviation rate is greater than a first preset deviation rate is judged.

[0101] If yes, it is determined that the unit to be detected has refrigerant leakage.

[0102] If no, it is determined that the unit to be detected does not have refrigerant leakage.

[0103] The part of the judgment logic is the foregoing, in the case that there is no refrigerant leakage, the current characteristic parameter detected is close to the historical characteristic parameter, that is, the deviation rate is small, and vice versa, in the case that there is refrigerant leakage, the current characteristic parameter detected is greatly different from the historical characteristic parameter, that is, the deviation rate is large.

[0104] Based on the judgment logic, the application can accurately determine whether the unit to be detected has refrigerant leakage according to the size of the deviation rate, so as to be used for the protection action of the unit to be detected to execute in advance.

[0105] Here, in a preferred embodiment of the application, the first preset deviation rate is 30%.

[0106] Further, when it is determined that the machine group to be detected has refrigerant leakage, the application further comprises:

[0107] calculating a deviation rate corresponding to the operating current of the machine group in the current characteristic parameter;

[0108] determining whether the determination result of the refrigerant leakage is a false positive according to the deviation rate corresponding to the operating current of the machine group.

[0109] The application sets up this process to further avoid the existence of false positives. When there is refrigerant leakage, the influence on the operating current of the machine group is the most intuitive, so the deviation rate corresponding to the operating current of the machine group can be directly calculated, and it is determined whether the previous determination result of the refrigerant leakage is a false positive.

[0110] Based on the above control process, the application can further avoid the occurrence of false positives in the determination result of the refrigerant leakage, and improve the determination accuracy of the refrigerant leakage.

[0111] See Figure 4 In the application, whether the determination result of the refrigerant leakage is a false positive is determined according to the deviation rate corresponding to the operating current of the machine group, which specifically comprises:

[0112] determining whether the deviation rate corresponding to the operating current of the machine group is greater than a first preset deviation rate;

[0113] If yes, the opening of the electronic expansion valve in the machine group to be detected is adjusted, and it is detected whether the current condition parameter has changed. If the current condition parameter has not changed, it is determined to be a false positive, otherwise it is determined to be a non-false positive.

[0114] If no, it is determined to be a false positive.

[0115] As described above, when there is refrigerant leakage, the influence on the operating current of the machine group is the most intuitive. If the deviation rate of the operating current of the machine group is less than the first preset deviation rate, it is reasonable to believe that the determination result of the refrigerant leakage at this time is a false positive, otherwise further detection is required.

[0116] The further detection scheme of the application is to adjust the opening of the electronic expansion valve, and then detect whether the current condition parameter has changed. Here, the opening of the electronic expansion valve is adjusted because the electronic expansion valve is used to adjust the refrigerant flow. If the opening of the electronic expansion valve is adjusted and the refrigerant flow does not change, the corresponding current condition parameter will not change at this time, and it is determined that the fault reason at this time is that the electronic expansion valve is stuck, not refrigerant leakage, so it needs to be determined to be a false positive.

[0117] If the current condition parameter changes, it indicates that the adjustment of the electronic expansion valve changes the refrigerant flow, and then adjusts the current adjustment parameter, at this time, the electronic expansion valve is in a normal state, and the fault reason is refrigerant leakage, and therefore, it is determined that it is not a misjudgment.

[0118] Based on the above control process, the present application can further avoid the misjudgment of the determination result of the refrigerant leakage, and improve the determination accuracy of the refrigerant leakage.

[0119] Please refer to Figure 5 When the determination result of the refrigerant leakage is determined to be non-misjudgment, the present application further comprises:

[0120] determining whether the deviation rate is less than a second preset deviation rate;

[0121] If yes, the compressor in the to-be-detected unit is subjected to frequency limiting treatment;

[0122] If no, the to-be-detected unit is subjected to shutdown treatment.

[0123] When the determination result of the refrigerant leakage is determined to be non-misjudgment, the present application further comprises:

[0124] If no, the to-be-detected unit is subjected to shutdown treatment.

[0125] That is, the present application gives corresponding solution strategies for different refrigerant leakage situations, avoiding the problem of performance deterioration of the air conditioning unit caused by refrigerant leakage.

[0126] In the present application, the condition parameters of the to-be-detected unit include: outdoor environment temperature, indoor environment temperature, and compressor frequency.

[0127] The characteristic parameters of the to-be-detected unit include: unit module high pressure, unit module low pressure, unit exhaust temperature, opening degree of the electronic expansion valve, and unit operating current.

[0128] Based on the above adjustment parameters and characteristic parameters, the present application can accurately determine whether the air conditioning unit has refrigerant leakage, avoiding the problem that the air conditioning unit cannot be detected when the refrigerant leaks, causing damage to the air conditioning unit.

[0129] Please refer to Figure 6 The specific process of the refrigerant leakage determination method in the present application is as follows:

[0130] The unit is started to operate, and the unit is the to-be-detected unit in the foregoing;

[0131] The air conditioning unit historical data is collected and recorded and stored to establish a large database, which contains condition parameters and characteristic parameter information, wherein the condition parameters contained in the database are actually the historical condition parameters in the foregoing, and the characteristic parameters are actually the historical characteristic parameters in the foregoing;

[0132] The condition parameters and characteristic parameters in the current unit operation data are detected in real time, wherein the condition parameters and characteristic parameters in the current unit operation data are actually the current condition parameters and the current characteristic parameters in the foregoing;

[0133] Whether there is current condition parameter corresponding operation data in the historical data of the large database is found, which is also the judgment of the two cases in the foregoing, if yes, it indicates that the large database has the historical condition parameters consistent with the current condition parameters, otherwise, it indicates that the large database does not have the historical condition parameters consistent with the current condition parameters;

[0134] When the judgment is yes, the current characteristic parameters are compared with the historical characteristic parameters, wherein Pg2=Pg0, Pd2=Pd0, Tp2=Tp0, Fn2=Fn0, and then the deviation rate is calculated by using the above-mentioned calculation model of the deviation rate; (in the foregoing, two calculation models are divided, in the flowchart, Pg2=Pg0, Pd2=Pd0, Tp2=Tp0, Fn2=Fn0 are directly set, and then the same calculation model is used, and both of the two implementation manners are feasible in actual application)

[0135] When the judgment is no, the historical characteristic parameters need to be corrected by using the calculation model for correcting the historical characteristic parameters, and then the deviation rate is calculated by using the above-mentioned calculation model of the deviation rate;

[0136] After the above-mentioned deviation rate is calculated, it is necessary to judge the range of the deviation rate, if less than 30%, that is, less than the first preset deviation rate, at this time, the action of continuing to observe and not processing is executed;

[0137] If it is in the interval of the first preset deviation rate and the second preset deviation rate, it is necessary to detect whether it is a false alarm, if not a false alarm, the compressor needs to be frequency-limited;

[0138] If it is greater than the second preset deviation rate, it is necessary to detect whether it is a false alarm, if not a false alarm, the compressor needs to be stopped.

[0139] From the above introduction, it can be seen that the present application has the following beneficial effects compared with the prior art:

[0140] 1、The present application can combine current condition parameters, current characteristic parameters, historical condition parameters and historical characteristic parameters to accurately determine whether the air conditioning unit has refrigerant leakage, avoiding the problem that the air conditioning unit cannot be detected when refrigerant leakage occurs, leading to damage to the air conditioning unit;

[0141] 2、The present application further determines whether it is a false judgment when determining that the air conditioning unit has refrigerant leakage, improving the accuracy of the present application in determining whether the air conditioning unit has refrigerant leakage;

[0142] 3、The present application gives corresponding solutions for different refrigerant leakage situations, avoiding the problem that the performance of the air conditioning unit deteriorates due to refrigerant leakage.

[0143] The present application also proposes an air conditioning unit, which has a refrigerant leakage judgment module that executes the above-mentioned refrigerant leakage judgment method.

[0144] The above is only a preferred embodiment of the present application and is not intended to limit the present application, and any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method of judging leakage of a refrigerant, characterized by, The method comprises the following steps: acquiring historical condition parameters of a to-be-detected unit and historical characteristic parameters corresponding to the historical condition parameters; detecting current condition parameters and current characteristic parameters of the to-be-detected unit; calculating a deviation rate of a historical characteristic parameter corresponding to the current condition parameter closest to the current condition parameter from the current characteristic parameter; judging whether the to-be-detected unit has refrigerant leakage according to the deviation rate; when calculating the deviation rate, further comprising the following steps: judging whether the current condition parameter is equal to the historical condition parameter closest to the current condition parameter; if yes, calculating the deviation rate from the historical characteristic parameter corresponding to the current condition parameter closest to the current condition parameter and the current characteristic parameter; if no, correcting the historical characteristic parameter corresponding to the current condition parameter closest to the current condition parameter, and calculating the deviation rate from the current characteristic parameter and the corrected historical characteristic parameter; the calculation model for correcting the historical characteristic parameter corresponding to the current condition parameter closest to the current condition parameter is as follows: Pg2= Pg0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0) Pd2= Pd0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1) Tp2= Tp0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y1 / Y0) Fn2= Fn0*(Tw1 / Tw0)*(Tn1 / Tn0)*(Y0 / Y1); wherein Pg0 is the uncorrected unit module high pressure of the to-be-detected unit, Pd0 is the uncorrected unit module low pressure of the to-be-detected unit, Tp0 is the uncorrected unit exhaust temperature of the to-be-detected unit, and Fn0 is the uncorrected electronic expansion valve opening degree of the to-be-detected unit; Pg2 is the corrected unit module high pressure of the to-be-detected unit, Pd2 is the corrected unit module low pressure of the to-be-detected unit, Tp2 is the corrected unit exhaust temperature of the to-be-detected unit, and Fn2 is the corrected electronic expansion valve opening degree of the to-be-detected unit; Tw1 is the current outdoor environment temperature, Tn1 is the current indoor environment temperature, and Y1 is the current compressor frequency; Tw0 is the historical outdoor environment temperature, Tn1 is the historical indoor environment temperature, and Y0 is the historical compressor frequency.

2. The method of claim 1, wherein judging whether the to-be-detected unit has refrigerant leakage according to the deviation rate comprises the following steps: judging whether the deviation rate is greater than a first preset deviation rate; if yes, determining that the to-be-detected unit has refrigerant leakage; if no, determining that the to-be-detected unit does not have refrigerant leakage.

3. The method of claim 2, wherein when determining that the to-be-detected unit has refrigerant leakage, further comprising the following steps: calculating a deviation rate corresponding to a unit operating current in the current characteristic parameter; judging whether the determination result of refrigerant leakage is a false positive according to the deviation rate corresponding to the unit operating current.

4. The method of claim 3, wherein judging whether the determination result of refrigerant leakage is a false positive according to the deviation rate corresponding to the unit operating current comprises the following steps: judging whether the deviation rate corresponding to the unit operating current is greater than a first preset deviation rate; If yes, the opening of the electronic expansion valve in the unit to be detected is adjusted, and whether the current condition parameter changes is detected, if the current condition parameter does not change, it is determined as a false judgment, otherwise it is determined as a non-false judgment. If no, it is determined as a false judgment.

5. The method of claim 3, wherein When the determination result of the refrigerant leakage is determined as a non-false judgment, further comprising: judging whether the deviation rate corresponding to the unit operating current in the current characteristic parameter is less than a second preset deviation rate; If yes, the compressor in the unit to be detected is frequency limited; If no, the unit to be detected is shut down.

6. An air conditioning unit characterized by, The air conditioning unit has a refrigerant leakage judgment module, and the refrigerant leakage judgment module executes the refrigerant leakage judgment method as claimed in any one of claims 1 to 5.

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