Air conditioner filth blockage detection method and device

Abstract

The invention relates to the technical field of air conditioner detection, in particular to an air conditioner filth blockage detection method and device.The method comprises the steps that when an air conditioner is in a refrigeration / heating mode, the current working frequency of a compressor in the air conditioner is obtained; judging whether the current working frequency is greater than the filth blockage alarm frequency; if not, entering a timing alarm stage; if yes, the filth blockage early warning frequency is calculated, and the wind side load size is obtained based on the current working frequency and the filth blockage early warning frequency; according to the refrigerant overheating / cooling degree, the ideal air outlet temperature and the actual air outlet temperature obtained according to the sampling period, the air side load size, the overheating / cooling degree, the ideal air outlet temperature and the actual air outlet temperature are comprehensively analyzed, and after filth blockage detection results are obtained, a timing alarm stage is started; in the timing alarm stage, if the timing time reaches a set alarm time threshold value, a filth blockage alarm signal is sent. According to the invention, the material cost can be reduced, the operation state of the air conditioning system is comprehensively evaluated from multiple dimensions, and the accuracy and reliability of filth blockage detection are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioner detection, and in particular to a method and device for detecting dirt and blockage of an air conditioner. Background Art

[0002] In the air conditioner system, the dust filter (hereinafter referred to as the "filter") occupies a key position. During the operation of the air conditioner, the air flow is as follows: first pass through the filter, then pass through the heat exchanger for heat exchange, and finally the heat-exchanged air is discharged from the air outlet or air duct and enters the indoor space to achieve cooling or heating functions. However, due to the suspended dust and impurities in the air, the filter, especially the filter of the air conditioner equipped with the fresh air function, is very easy to accumulate dust. A large amount of dust accumulation will block the air inlet, and then hinder the air from flowing into the heat exchanger for heat exchange, causing the performance of the air conditioner to drop significantly. In addition, many bacteria are easy to attach to the dust that blocks the filter, and spread to the indoor environment with the air outlet of the air conditioner. If this continues for a long time, it will have an adverse effect on human health.

[0003] At present, the main detection methods for air conditioner filters are fan power detection method and pressure difference detection method before and after the filter. The principle of fan power detection method is based on the fact that a constant speed fan will output different powers under different wind resistance conditions, so as to judge the state of the filter. However, this method is affected by many factors such as air conditions, installation environment, equipment sealing performance, voltage fluctuations, and motor aging, resulting in poor accuracy of the detection results. False alarms are prone to occur in actual application scenarios, which in turn affects the user experience. Although the pressure difference detection method before and after the filter has a high measurement accuracy, this method requires two pressure sensors, which not only increases the cost investment, but also takes up additional installation space. Summary of the invention

[0004] In order to solve the problems in the prior art that the filter blockage detection device is high in cost, occupies a large space, or is greatly affected by environmental factors and has inaccurate detection, the present invention provides an air conditioner blockage detection method and device, wherein the detection methods include three methods, and the first detection method includes the following steps:

[0005] Step S1, when the air conditioner is in cooling mode, obtaining the current operating frequency of the compressor in the air conditioner;

[0006] Step S2, calculating the dirty blockage alarm frequency of the compressor, and determining whether the current operating frequency is greater than the dirty blockage alarm frequency:

[0007] If not, execute step S4 to enter the timing alarm stage;

[0008] If yes, calculate the dirty blockage warning frequency of the compressor, and obtain the wind side load size based on the current working frequency and the dirty blockage warning frequency;

[0009] Step S3, obtaining the superheat, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to a preset data sampling period, analyzing the wind side load size, the superheat, the ideal outlet air temperature and the actual outlet air temperature to obtain a dirty blockage detection result, and then executing step S4;

[0010] Step S4: Enter the timing alarm phase and obtain the timing time t j , using the data sampling period to update the time t j , get the updated time t j * ;

[0011] Step S5: Determine the time t j * Is it greater than or equal to the set system running time threshold t * :

[0012] If not, return to step S1 to continue real-time monitoring of the compressor operating frequency;

[0013] If so, send a dust filter dirty blockage alarm signal;

[0014] Wherein, the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions:

[0015] f2≤f0≤f1≤f3 (1)

[0016] Among them, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor.

[0017] In one embodiment of the present invention, in step S2, the method for obtaining the wind side load size based on the current operating frequency and the dirt blockage warning frequency is as follows:

[0018] Determine whether the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and a constant term, where the constant term is used to set a fault tolerance interval:

[0019] If not, it means that the wind side load size is normal, and the process returns to step S1 to continue to monitor the compressor operating frequency in real time;

[0020] If so, it means that the wind side load becomes smaller, so the operating frequency of the compressor decreases, and the wind side load size at this time is obtained.

[0021] In one embodiment of the present invention, in step S3, the method for analyzing the wind side load size, the superheat, the ideal air outlet temperature and the actual air outlet temperature to obtain the dirty blockage detection result is as follows:

[0022] Step S31, under the condition that the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and the constant term, obtain the temperature T1 of the liquid refrigerant in the evaporator after absorbing heat and evaporating into a gaseous state, the refrigerant temperature T3 output at the evaporator outlet, the actual outlet air temperature T6 and the ideal outlet air temperature T7 according to the preset sampling period, and calculate the superheat degree of the refrigerant δ1=(T3-T1) based on T1 and T3;

[0023] Step S32: setting the superheat threshold T9 of the evaporator, and judging whether the superheat δ1 is less than or equal to the superheat threshold T9:

[0024] If not, return to step S1 to continue real-time monitoring of the compressor operating frequency;

[0025] If yes, execute step S33;

[0026] Step S33: setting a temperature deviation threshold value T10, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the temperature deviation threshold value T10:

[0027] If not, return to step S1 to continue real-time monitoring of the compressor operating frequency;

[0028] If yes, after obtaining the dirt and blockage detection result, step S4 is executed to enter the timing alarm stage.

[0029] The present invention also provides a second method for detecting dirt and blockage of an air conditioner, the method comprising the following steps:

[0030] Step a, when the air conditioner is in heating mode, obtaining the current operating frequency of the compressor in the air conditioner;

[0031] Step b, calculating the dirty blockage alarm frequency of the compressor, and determining whether the current operating frequency is greater than the dirty blockage alarm frequency:

[0032] If not, execute step d and enter the timing alarm stage;

[0033] If yes, calculate the dirty blockage warning frequency of the compressor, and obtain the wind side load size based on the current working frequency and the dirty blockage warning frequency;

[0034] Step c, obtaining the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to the preset data sampling period, analyzing the wind side load size, the subcooling degree, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirty blockage detection result, then entering the timing alarm stage, and executing step d;

[0035] Step d: Get the timing time t j, using the data sampling period to update the time t j , get the updated time t j * ;

[0036] Step e: Determine the time t j * Is it greater than or equal to the set system running time threshold t * :

[0037] If not, return to step a and continue to monitor the compressor operating frequency in real time;

[0038] If so, send a dust filter dirty blockage alarm signal;

[0039] Wherein, the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions:

[0040] f2≤f0≤f1≤f3 (2)

[0041] Among them, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor.

[0042] In one embodiment of the present invention, in step b, the method for obtaining the wind side load size based on the current operating frequency and the dirt blockage warning frequency is as follows:

[0043] Determine whether the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and a constant term, where the constant term is used to set a fault tolerance interval:

[0044] If not, it means that the wind side load size is normal, and the process returns to step a to continue real-time monitoring of the compressor operating frequency;

[0045] If so, it means that the wind side load becomes smaller, so the operating frequency of the compressor decreases, and the wind side load size at this time is obtained.

[0046] In one embodiment of the present invention, in step c, the method for analyzing the wind side load size, the supercooling degree, the ideal air outlet temperature and the actual air outlet temperature to obtain the dirty blockage detection result is as follows:

[0047] Step c1, under the condition that the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and the constant term, obtain the temperature T2 of the gaseous refrigerant in the condenser after releasing heat and condensing into liquid, the refrigerant temperature T4 output from the condenser outlet, the actual outlet air temperature T6 and the ideal outlet air temperature T7 according to the preset data sampling period, and calculate the refrigerant subcooling δ2=(T2-T4) based on T2 and T4;

[0048] Step c2, setting the subcooling threshold T9 and the heating temperature difference correction coefficient k of the condenser, adjusting the subcooling threshold T9 by using the heating temperature difference correction coefficient k, obtaining the adjusted subcooling threshold, and judging whether the subcooling δ2 is less than or equal to the adjusted subcooling threshold:

[0049] If not, return to step a and continue to monitor the compressor operating frequency in real time;

[0050] If yes, go to step c3;

[0051] Step c3, setting a temperature deviation threshold T10, adjusting the temperature deviation threshold T10 using the heating temperature difference correction coefficient k, obtaining an adjusted temperature deviation threshold, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the adjusted temperature deviation threshold:

[0052] If not, return to step a and continue to monitor the compressor operating frequency in real time;

[0053] If yes, after obtaining the dirty and blocked detection result, execute step a and enter the timing alarm stage.

[0054] In one embodiment of the present invention, the method for calculating the dirty blockage alarm frequency f0 of the compressor is as follows:

[0055] Under the environmental condition of relative humidity n1, the inlet air temperature T is obtained, and the ideal heat transfer Q is obtained by data fitting. e1 and the inlet air temperature T:

[0056] Q e1 =a1T 2 +b1T+c1 (3)

[0057] Get the rated operating frequency f of the compressor e and rated cooling capacity Q0, based on the rated operating frequency f e , the rated cooling capacity Q0, and the cooling capacity Q1 at the dirty blockage alarm frequency f0 is obtained:

[0058] Q1=Q0·f0 / f e (4)

[0059] Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then:

[0060] V1=V e ·η (5)

[0061] According to the law of conservation of energy, during the cooling process of the air conditioner, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so:

[0062] Q e1 V1=Q1·V e (6)

[0063] Arranging formulas (3) to (6) yields:

[0064]

[0065] Among them, a1, b1, and c1 are all fitting parameters.

[0066] In one embodiment of the present invention, the method for calculating the compressor dirty blockage warning frequency f1 is as follows:

[0067] Under the environmental condition of relative humidity n2, the inlet air temperature T is obtained, and the ideal heat transfer Q is obtained by data fitting. e2 and the inlet air temperature T:

[0068] Q e2 =a2T 2 +b2T+c2 (8)

[0069] Get the rated operating frequency f of the compressor e and rated cooling capacity Q0, based on the rated operating frequency f e , the rated cooling capacity Q0, and the cooling capacity Q2 at the dirty blockage warning frequency f1 is obtained:

[0070] Q2=Q0·f1 / f e (9)

[0071] Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then:

[0072] V1=V e ·η (10)

[0073] According to the law of conservation of energy, during the cooling process of the air conditioner, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so:

[0074] Q e2 V1=Q2·V e (11)

[0075] Arranging formulas (8) to (11) yields:

[0076]

[0077] Among them, a2, b2, and c2 are all fitting parameters.

[0078] Based on the same inventive concept of the above technical solution, the present invention also provides a third method for detecting dirty air conditioner blockage, the detection method includes the steps of the first detection method and the second detection method, including:

[0079] Obtain the current continuous running time of the device, and determine whether the current continuous running time is greater than a preset first time threshold:

[0080] If not, return to continue monitoring the continuous operation time of the device;

[0081] If yes, determine whether the device is operating in cooling mode or heating mode:

[0082] If the equipment operation mode is cooling mode, the dust filter is tested for dirtiness and blockage using the corresponding first detection method to obtain a detection result;

[0083] If the equipment operation mode is the heating mode, the dust filter is tested for dirtiness and blockage using the corresponding second detection method to obtain a detection result.

[0084] The present invention also provides an air conditioner dirt and blockage detection device, comprising a control unit and a plurality of temperature sampling modules connected to the control unit, wherein the control unit uses the air conditioner dirt and blockage detection method to perform dirt and blockage detection on the dust filter.

[0085] The above technical solution of the present invention has the following advantages compared with the prior art:

[0086] The present invention provides a detection method for judging the dirty and blocked condition of an air conditioner by relying on the temperature values ​​of multiple measuring points. In the application scenario of existing equipment, if the equipment has sufficient reserved temperature sensor interfaces, temperature sensors can be added in the subsequent stage, and the program can be updated to achieve an effect similar to that of a new device using the detection method. This detection method has significant advantages: first, it abandons the wind pressure sensor required in the traditional detection method, effectively reduces the material cost of the air conditioner, and plays a positive role in optimizing the product cost structure; second, it can significantly reduce the misjudgment caused by external interference or internal parameter fluctuations during the operation of the system, and improve the accuracy and reliability of the detection; third, it helps to ensure that the air conditioning system is always in a good operating state and maintains stable and efficient performance; fourth, from the perspective of user experience, with accurate detection and stable operation, it effectively improves the customer experience in the process of using the air conditioner and enhances the user's satisfaction and trust in the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0088] Figure 1 It is a flow chart of a method for detecting dirt and blockage of an air conditioner in a cooling mode provided in an embodiment of the present invention;

[0089] Figure 2 It is a specific flow chart of a method for detecting air conditioner dirtiness and blockage in cooling mode provided in an embodiment of the present invention;

[0090] Figure 3 is a flow chart of a method for detecting air conditioner dirtiness and blockage in heating mode provided in an embodiment of the present invention;

[0091] Figure 4 It is a specific flow chart of a method for detecting dirty blockage of an air conditioner in a heating mode provided in an embodiment of the present invention;

[0092] Figure 5 It is a flow chart of a method for detecting dirty air conditioner blockage provided in an embodiment of the present invention;

[0093] Figure 6 It is a structural schematic diagram of an air conditioner dirtiness and blockage detection device provided in an embodiment of the present invention;

[0094] Figure 7 is a schematic diagram of the installation position of the temperature sampling module provided in an embodiment of the present invention;

[0095] Explanation of the reference numerals in the specification: 100, control unit; 200, temperature sampling module; 1, evaporator; 2, condenser; 3, compressor; 10, first sensor; 20, second sensor; 30, third sensor; 40, fourth sensor. DETAILED DESCRIPTION

[0096] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0097] Embodiment 1

[0098] See also Figure 1 and Figure 2 As shown, the present invention provides a method for detecting dirt and blockage of an air conditioner, the detection method comprising the following steps:

[0099] Step S1, when the air conditioner is in cooling mode, the current operating frequency f of the compressor in the air conditioner is obtained because the operating frequency of the compressor can directly reflect its refrigerant displacement (enthalpy value);

[0100] Step S2, calculating the dirty blockage alarm frequency f0 of the compressor through a data fitting process using the air inlet temperature T of the evaporator and the set dirty blockage percentage η, and judging whether the current operating frequency f is greater than the dirty blockage alarm frequency f0:

[0101] If not, it indicates that the system is dirty and blocked in a serious impact range, and step S4 is executed to enter the timing alarm stage;

[0102] If yes, it means that the current system may have a certain degree of dirty blockage state and still needs further monitoring. At this time, the dirty blockage warning frequency f1 of the compressor is calculated through the data fitting process through the evaporator's inlet air temperature T and the set dirty blockage percentage η, and the wind side load size is obtained based on the current operating frequency f and the dirty blockage warning frequency f1;

[0103] Step S3, obtaining the superheat, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to a preset data sampling period, analyzing the wind side load size, the superheat, the ideal outlet air temperature and the actual outlet air temperature to obtain a dirty blockage detection result, and then executing step S4;

[0104] Step S4: Enter the timing alarm phase and obtain the timing time t j , using the data sampling period to update the time t j , get the updated time t j * ;

[0105] Step S5: Determine the time t j * Is it greater than or equal to the set system running time threshold t * :

[0106] If not, return to step S1 to continue real-time monitoring of the compressor operating frequency;

[0107] If so, send a dust filter dirty blockage alarm signal;

[0108] In order to make the dirty blockage alarm frequency f0 and the dirty blockage warning frequency f1 within a reasonable range, a clear frequency definition basis is provided for accurately judging whether the air conditioner is dirty blocked and the different degrees of dirty blockage, so the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions:

[0109] f2≤f0≤f1≤f3 (1)

[0110] In the formula, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor. Setting the dirty blockage alarm frequency f0 to be less than or equal to the dirty blockage warning frequency f1 can prevent the system from issuing a dirty blockage alarm when there is a slight abnormality.

[0111] It can be seen from the above technical solutions that the present invention integrates multiple key parameters to perform dirty blockage detection, which can comprehensively evaluate the operating status of the air-conditioning system from multiple dimensions, greatly improving the accuracy and reliability of dirty blockage detection. The superheat of the refrigerant reflects the evaporation of the refrigerant in the evaporator. The comparison between the ideal air outlet temperature and the actual air outlet temperature can intuitively reflect the cooling effect of the air conditioner, and the wind side load size is closely related to the ventilation condition of the filter. By comprehensively analyzing these parameters, it is possible to more accurately determine whether the filter is dirty and blocked and the degree of dirty blockage, providing users with more accurate maintenance suggestions.

[0112] Further, in step S2, when the current operating frequency f is greater than the dirty blockage alarm frequency f0, the method for obtaining the wind side load size based on the current operating frequency f and the dirty blockage warning frequency f1 is as follows:

[0113] Considering that the compressor frequency will fluctuate to a certain extent under actual operating conditions, in order to prevent misjudgment of abnormal wind side load or filter blockage due to normal frequency fluctuations, a constant term is introduced to set the fault tolerance interval to further determine whether the current operating frequency f is less than or equal to the sum of the blockage warning frequency f1 and the constant term:

[0114] If not, it indicates that the wind side load is within the normal range, and the process returns to step S1 to continue real-time monitoring of the compressor operating frequency;

[0115] If so, it means that the wind side load becomes smaller, which in turn causes the operating frequency of the compressor to decrease, and the wind side load size at this time is obtained.

[0116] Further, in step S3, under the condition that the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and the constant term, the method of analyzing the wind side load size, the superheat, the ideal air outlet temperature and the actual air outlet temperature to obtain the dirty blockage detection result is as follows:

[0117] Step S31, according to the preset data sampling period, obtain the temperature T1 when the liquid refrigerant in the evaporator absorbs heat and evaporates into gas, the refrigerant temperature T3 output from the evaporator outlet, the actual air outlet temperature T6 and the ideal air outlet temperature T7, and calculate the refrigerant superheat δ1=(T3-T1) based on the obtained T1 and T3, so as to grasp the state change of the refrigerant in the evaporator in real time;

[0118] Step S32: To preliminarily screen out the possible abnormalities of the heat exchanger, set the superheat threshold T9 of the evaporator, and determine whether the superheat δ1 is less than or equal to the superheat threshold T9:

[0119] If not, it indicates that there is no obvious abnormality in the state of the refrigerant in the current system, and the process returns to step S1 to continue to monitor the operating frequency of the compressor in real time;

[0120] If yes, it means that the refrigerant state may be affected by some factors and further judgment is required, and step S33 is executed;

[0121] Step S33: setting a temperature deviation threshold value T10, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the temperature deviation threshold value T10:

[0122] If not, it means that the actual air outlet temperature is close to the ideal air outlet temperature, and the system is running relatively normally, and the process returns to step S1 to continue to monitor the compressor operating frequency in real time;

[0123] If yes, it indicates that the actual air flow is significantly different from the ideal state. At this time, the timing alarm phase is entered and the timing time t is obtained. j , using the data sampling period t s Update the time t j , get the updated time t j * =t j +t s ;

[0124] Step S34: To avoid false alarms caused by various factors, a system operation time threshold t is set. * The threshold value must be guaranteed to meet the following conditions within the corresponding time period: the current operating frequency f is less than or equal to the sum of the dirty and blocked warning frequency f1 and the constant term, the refrigerant superheat δ1 is less than or equal to the superheat threshold T9, and the difference between the ideal outlet air temperature T7 and the actual outlet air temperature T6 is greater than or equal to the temperature deviation threshold T10. When the filter is accurately determined to be dirty and blocked, the system should immediately issue an alarm signal.

[0125] Based on practical experience, the system running time threshold t * The reference setting range is 15 to 30 minutes. For systems with a fast system adjustment response speed, a relatively small value can be selected within this range to achieve more timely and accurate dirt blockage detection and alarm. j * Is it greater than or equal to the system running time threshold t * :

[0126] If not, it indicates that the system has not yet reached a stable operating state, and accurate dirty and blocked judgment cannot be made at this time. In this case, return to step S1 and continue to monitor the compressor operating frequency in real time;

[0127] If yes, it means that the system has completed stable adjustment, and the dirty and blocked detection results can be obtained based on the current operating data. Once the test results show that the dust filter is dirty and blocked, the system will immediately send a dust filter dirty and blocked alarm signal to prompt relevant personnel to take maintenance measures in time.

[0128] Embodiment 2

[0129] See also Figure 3 and Figure 4 As shown, the present invention also provides a method for detecting dirt and blockage of an air conditioner, the detection method comprising the following steps:

[0130] Step a, when the air conditioner is in heating mode, since the operating frequency of the compressor can directly reflect its refrigerant displacement (enthalpy value), the current operating frequency f of the compressor in the air conditioner is obtained;

[0131] Step b, calculating the dirty blockage alarm frequency f0 of the compressor according to the ambient temperature T and the set dirty blockage percentage η, and judging whether the current operating frequency f is greater than the dirty blockage alarm frequency f0:

[0132] If not, it indicates that the system is dirty and blocked in a serious impact range, and step S4 is executed to enter the timing alarm stage;

[0133] If yes, it means that the current system may have a certain degree of dirty blockage state and still needs further monitoring. At this time, the dirty blockage warning frequency f1 of the compressor is calculated through the data fitting process through the inlet air temperature T of the condenser and the set dirty blockage percentage η, and the wind side load size is obtained based on the current operating frequency f and the dirty blockage warning frequency f1;

[0134] Step c, obtaining the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to a preset data sampling period, analyzing the wind side load size, the subcooling degree, the ideal outlet air temperature and the actual outlet air temperature to obtain a dirty blockage detection result, and then executing step d;

[0135] Step d: Enter the timing alarm phase and obtain the timing time t j , using the data sampling period to update the time t j , get the updated time t j * ;

[0136] Step e: Determine the time t j * Is it greater than or equal to the set system running time threshold t * :

[0137] If not, return to step a and continue to monitor the compressor operating frequency in real time;

[0138] If so, send a dust filter dirty blockage alarm signal;

[0139] Wherein, the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions:

[0140] f2≤f0≤f1≤f3 (2)

[0141] Among them, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor.

[0142] It can be seen from the above technical solutions that the present invention integrates multiple key parameters to perform dirty and blocked detection, which can comprehensively evaluate the operating status of the air-conditioning system from multiple dimensions, greatly improving the accuracy and reliability of dirty and blocked detection. The supercooling of the refrigerant reflects the condensation of the refrigerant in the condenser. The comparison between the ideal air outlet temperature and the actual air outlet temperature can intuitively reflect the heating effect of the air conditioner, and the wind side load size is closely related to the ventilation condition of the filter. By comprehensively analyzing these parameters, it is possible to more accurately determine whether the filter is dirty and blocked and the degree of dirty and blocked, providing users with more accurate maintenance suggestions.

[0143] Furthermore, in step b, when the current operating frequency f is greater than the dirty blockage alarm frequency f0, the method for obtaining the wind side load size based on the current operating frequency f and the dirty blockage warning frequency f1 is as follows:

[0144] Considering that the compressor frequency will fluctuate to a certain extent under actual operating conditions, in order to prevent misjudgment of abnormal wind side load or filter blockage due to normal frequency fluctuations, a constant term is introduced to set the fault tolerance interval, and further determine whether the current operating frequency f is less than or equal to the sum of the blockage warning frequency f1 and the constant term. The constant term is used to set the fault tolerance interval:

[0145] If not, it means that the wind side load size is normal, and the process returns to step a to continue real-time monitoring of the compressor operating frequency;

[0146] If so, it means that the wind side load becomes smaller, so the operating frequency of the compressor decreases, and the wind side load size at this time is obtained.

[0147] Further, in step c, under the condition that the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and the constant term, the method for obtaining the dirty blockage detection result according to the wind side load size, the supercooling degree, the ideal outlet air temperature and the actual outlet air temperature is as follows:

[0148] Step c1, according to the preset data sampling period, obtain the temperature T2 of the gaseous refrigerant in the condenser after releasing heat and condensing into liquid, the refrigerant temperature T4 output from the condenser outlet, the actual outlet air temperature T6 and the ideal outlet air temperature T7, and calculate the refrigerant supercooling δ2=(T2-T4) based on the obtained T2 and T4, so as to grasp the state change of the refrigerant in the condenser in real time;

[0149] Step c2: In order to preliminarily screen out possible abnormalities in the heat exchanger, it is necessary to set the subcooling threshold T9 of the condenser. Since the heating process is more affected by environmental factors, the heating temperature difference correction coefficient k also needs to be set. From a theoretical perspective, T9 should be set to 0K to indicate that the heat exchanger is not superheated. However, since the temperature sensor is easily affected by environmental factors, a certain measurement deviation will occur; and if the sensor itself is not accurate enough, the subcooling measurement value will fluctuate around 0K. Therefore, T9 is appropriately expanded to 1K to eliminate the impact of system errors. The subcooling threshold T9 is adjusted using the heating temperature difference correction coefficient k to obtain the adjusted subcooling threshold = k×T9, and it is determined whether the subcooling δ2 is less than or equal to the adjusted subcooling threshold:

[0150] If not, it indicates that there is no obvious abnormality in the state of the refrigerant in the current system, and the process returns to step a to continue to monitor the operating frequency of the compressor in real time;

[0151] If yes, it means that the refrigerant status may be affected by some factors and further judgment is needed. In this case, execute step c3;

[0152] Step c3, setting a temperature deviation threshold T10, adjusting the temperature deviation threshold T10 using the heating temperature difference correction coefficient k, obtaining an adjusted temperature deviation threshold = k × T10, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the adjusted temperature deviation threshold:

[0153] If not, it means that the actual air outlet temperature is close to the ideal air outlet temperature, and the system is running relatively normally. Return to step a and continue to monitor the compressor operating frequency in real time;

[0154] If yes, it indicates that the actual air flow is significantly different from the ideal state. At this time, the timing alarm phase is entered and the timing time t is obtained. j , using the data sampling period t s Update the time t j , get the updated time t j * =t j +t s ;

[0155] Step c4: To avoid false alarms caused by various factors, a system operation time threshold t is set. * The threshold value must be guaranteed to meet the following conditions within the corresponding time period: the current operating frequency f is less than or equal to the sum of the dirty and blocked warning frequency f1 and the constant term, the refrigerant subcooling degree δ2 is less than or equal to the adjusted subcooling degree threshold, and the difference between the ideal outlet air temperature T7 and the actual outlet air temperature T6 is greater than or equal to the adjusted temperature deviation threshold. When the filter is accurately determined to be dirty and blocked, the system should immediately issue an alarm signal.

[0156] Based on practical experience, the system running time threshold t * The reference setting range is 15 to 30 minutes. For systems with a fast system adjustment response speed, a relatively small value can be selected within this range to achieve more timely and accurate dirt blockage detection and alarm. j * Is it greater than or equal to the system running time threshold t * :

[0157] If not, return to step a and continue to monitor the compressor operating frequency in real time;

[0158] If so, the dirty and blocked detection result is obtained, and a dust filter dirty and blocked alarm signal is sent.

[0159] Furthermore, Table 1 is a cooling air enthalpy difference table, which is calculated according to constant relative humidity and records the corresponding wet bulb temperature, water content, density, relative humidity, dew point temperature, enthalpy value, enthalpy difference and other data at different dry bulb temperatures. Table 2 is a heating air enthalpy difference table, which is calculated according to a constant water content of 1g / kg and also records the relevant humidity, density, dew point temperature, enthalpy value, enthalpy difference and other data at different dry bulb temperatures. Based on the data in Tables 1 and 2, the method for obtaining the heating temperature difference correction coefficient k is as follows:

[0160] Table 1 Refrigeration air enthalpy difference table

[0161]

[0162] Table 2 Heating air enthalpy difference table

[0163]

[0164] By comparing the enthalpy difference data in Table 1 and Table 2, it is found that when the temperature difference is the same, the heating enthalpy difference is approximately 3.5 times the cooling enthalpy difference. This means that when absorbing or releasing the same amount of energy, the temperature change in the heating process is 3.5 times that in the cooling process. However, the water content in the air will affect this multiple relationship. In an environment with high humidity, this multiple will decrease, even as low as about 3 times. Taking the above factors into consideration, the value range of the heating temperature difference correction coefficient k is determined to be between 2.4 and 3.5. In actual application scenarios, it is necessary to flexibly select an appropriate k value based on the specific use environment, sensor graduation accuracy and other actual conditions.

[0165] Taking a common household wall-mounted air conditioner as an example, when the air inlet parameters of the indoor unit are 27 / 19.5℃, under the condition of keeping relative humidity and air pressure constant, by querying the air enthalpy value data at different temperatures, it is calculated that when the temperature changes, the enthalpy difference changes by about 83% of that at 35 / 28℃. Based on this proportional relationship, the k value to be selected at this time is k=3.5×83%=2.9.

[0166] For example, when customizing fresh air air conditioners in Shenzhen, the meteorological parameters used are 33 / 27.9℃ (constant relative humidity). When querying the air enthalpy value data under the same constant relative humidity and pressure conditions, it can be seen that the enthalpy difference change under the same temperature change is about 68% of that at 35 / 28℃. According to the above calculation method, the k value at this time is k=3.5×68%=2.4. For other types of air conditioning equipment, this method can also be used to correct the k value.

[0167] Embodiment 3

[0168] Based on the same inventive concept of the above technical solution, the present invention also provides a third method for detecting air conditioner dirtiness and blockage, which includes the steps of the first detection method and the second detection method. Figure 5 As shown, the third method for detecting dirty air conditioner blockage includes:

[0169] Since the compressor needs a certain amount of time to stabilize, the first time threshold is set to 5 minutes according to the 3-5 minutes of the home system. After the system stabilizes, the judgment cycle begins to avoid false alarms of system instability. Get the current continuous running time t of the device, and determine whether the current continuous running time is greater than the first time threshold t1:

[0170] If not, return to continue monitoring the continuous operation time t of the device;

[0171] If yes, determine whether the device is operating in cooling mode or heating mode:

[0172] If the operation mode of the device is the cooling mode, the dust filter is detected to be dirty and blocked by the detection method in the corresponding embodiment 1 to obtain the detection result. The implementation process is the same as the implementation method described in the embodiment 1, and will not be described here.

[0173] If the equipment operation mode is the heating mode, the dust filter is detected to be dirty and blocked by the detection method in the corresponding embodiment 2 to obtain the detection result. The implementation process is the same as the implementation method described in the embodiment 2 and will not be repeated here.

[0174] Furthermore, in Examples 1 to 3, for different outdoor environments, when the air conditioner processes the air to a target temperature of 12°C and a relative humidity of 95%, the enthalpy difference is different. In view of the fact that the setting of the dirty blockage alarm frequency f0 needs to be inclined to a more severe situation where the alarm is easier, in order to ensure the consistency of the calculation conditions, the relevant calculations are uniformly performed at a relative humidity of 35% (relatively dry ambient humidity conditions). Table 3 is part of the calculation data for reference.

[0175] Table 3 Enthalpy difference of air with relative humidity of 35%

[0176] Dry bulb temperature t 28 30 32 34 36 38 40 12 Wet bulb temperature ts 17.66 19.15 20.62 22.1 23.6 25.1 26.6 11.5 Moisture content 8.22 9.25 10.37 11.61 13.01 14.55 16.24 8.23 Relative humidity 34.9％ 35.0％ 34.9％ 34.9％ 34.9％ 34.9％ 34.9％ 94.3％ Density kg / m3 1.166 1.158 1.150 1.141 1.133 1.125 1.116 1.231 Enthalpy kj / kg 49.26 53.95 58.86 64.10 69.76 75.79 82.22 32.89 Enthalpy difference kj / kg 16.38 21.07 25.97 31.22 36.88 42.91 49.33 0.00

[0177] Therefore, the method for calculating the compressor's dirty blockage alarm frequency f0 is as follows:

[0178] Under the specific environmental condition of relative humidity n1=35%, the inlet air temperature T is collected (in cooling condition, the inlet air temperature is the inlet air temperature of the evaporator; in heating condition, it is the inlet air temperature of the condenser). Then, according to the constant mass flow calculation, the ideal heat exchange capacity Q is obtained by using the data fitting method. e1 The functional relationship between the inlet air temperature T is:

[0179] Q e1 =a1T 2 +b1T+c1=0.0451·T 2 -0.3256·T-9.806 (3)

[0180] Assume that the compressor operates at rated frequency f e =60Hz assumes rated summer conditions, under which the dry bulb temperature is 35°C, the wet bulb temperature is 28°C, the enthalpy difference is 56.34 kJ / kg, and the air density is 1.131 kg / m 3 At this time, the corresponding rated cooling capacity Q0 = 64.44 kJ / m 3 .

[0181] Since the compressor is in the low frequency band, the speed is proportional to the displacement, and when the environmental parameters are the same and do not exceed the heat exchange capacity of the heat exchanger, the displacement is proportional to the air conditioning cooling or heating capacity. At the same time, under normal conditions where the load is not too large, the compressor speed is proportional to the air conditioning cooling or heating capacity. Therefore, based on the rated operating frequency f e and the rated cooling capacity Q0, the cooling capacity Q1 at the dirty blockage alarm frequency f0 is obtained:

[0182]

[0183] During the operation of the air conditioning system, if the filter is dirty or blocked, the air volume will change. Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then:

[0184] V1=V e ·η (5)

[0185] According to the law of energy conservation, in the cooling process of air conditioners with the same compressor frequency and evaporation temperature (ignoring the sensible heat exchange part with very small heat exchange amount), regardless of whether there is dirt blockage, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so:

[0186] Q e1 V1=Q1·V e (6)

[0187] Arranging formulas (3) to (6) yields:

[0188]

[0189] Among them, a1=0.0451, b1=-0.3256, c1=-9.806 are all fitting parameters.

[0190] Furthermore, in Examples 1 to 3, for different outdoor environmental conditions, when the air conditioning system processes the air to the target temperature (12°C) and the relative humidity reaches 95%, the corresponding enthalpy difference shows differences. Since under normal circumstances, ordinary air conditioning equipment usually does not have the function of measuring the outdoor wet-bulb temperature, in order to ensure the consistency and feasibility of the calculation, the relevant calculations are uniformly performed according to the common relative humidity of 60%. Table 4 is part of the calculation data for reference.

[0191] Table 4 Enthalpy difference of air with relative humidity of 60%

[0192]

[0193]

[0194] Therefore, the method for calculating the compressor dirty blockage warning frequency f1 is as follows:

[0195] Under the specific environmental condition of relative humidity n2 = 60%, the inlet air temperature T is collected (in cooling condition, the inlet air temperature is the inlet air temperature of the evaporator; in heating condition, it is the inlet air temperature of the condenser). Then, according to the constant mass flow calculation, the ideal heat exchange capacity Q is obtained by using the data fitting method. e2 The functional relationship between the inlet air temperature T is:

[0196] Q e2 =a2T 2 +b2T+c2=0.0617·T 2 +0.137·T-15.989 (8)

[0197] Assume that the compressor operates at rated frequency f e =60Hz assumes rated summer conditions, under which the dry bulb temperature is 35°C, the wet bulb temperature is 28°C, the enthalpy difference is 56.34 kJ / kg, and the air density is 1.131 kg / m 3 At this time, the corresponding rated cooling capacity Q0 = 64.44 kJ / m 3 . Get the rated operating frequency f of the compressor e and rated cooling capacity Q0, based on the rated operating frequency f e , the rated cooling capacity Q0, and the cooling capacity Q2 at the dirty blockage warning frequency f1 is obtained:

[0198]

[0199] During the operation of the air conditioning system, if the filter is dirty or blocked, the air volume will change. Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then:

[0200] V1=V e ·η (10)

[0201] According to the law of conservation of energy, during the cooling process of the air conditioner, regardless of whether there is dirt or blockage, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so:

[0202] Q e2 V1=Q2·V e (11)

[0203] Arranging formulas (8) to (11) yields:

[0204]

[0205] Among them, a2=0.0617, b2=0.137, c2=-15.989 are all fitting parameters.

[0206] Embodiment 4

[0207] See also Figure 6 and Figure 7 As shown, the present invention also provides an air conditioner dirtiness and blockage detection device, including a control unit 100 and a temperature sampling module 200 connected to the control unit 100, and the control unit 100 uses the air conditioner dirtiness and blockage detection method described in Example 3 to detect dirtiness and blockage on the dust filter.

[0208] The temperature sampling module 200 includes a first sensor 10, a second sensor 20, a third sensor 30 and a fourth sensor 40. The first sensor 10 is arranged at the refrigerant outlet of the evaporator to obtain the refrigerant temperature T3 in the cooling mode; the second sensor 20 is arranged at the refrigerant outlet of the condenser to obtain the refrigerant temperature T4 in the heating mode; the third sensor 30 is placed at the air outlet side of the indoor unit to monitor the actual air outlet temperature T6; and the fourth sensor 40 is installed at a designated position to measure the ambient temperature T.

[0209] Next, the working principle of the air conditioner is explained:

[0210] In the cooling mode, the liquid refrigerant quickly vaporizes in the low-pressure environment of the evaporator 1, and absorbs a large amount of air heat through heat exchange with the air flowing through it, thereby cooling the air and achieving a cooling effect. At the same time, the water vapor in the air is cooled and liquefied and discharged. The gaseous refrigerant discharged from the evaporator 1 is compressed into a high-temperature and high-pressure state by the compressor 3 and then transported to the condenser 2. The condenser 2 serves as the "heat release end", in which the high-temperature and high-pressure gaseous refrigerant releases heat to the external environment, and dissipates the heat to the outside with the help of heat dissipation devices such as fans. After the gaseous refrigerant is cooled and liquefied, it is depressurized by the throttle valve and enters the evaporator 1 again. This cycle is repeated to achieve the transfer of indoor heat to the outside.

[0211] In heating mode, the functions of evaporator 1 and condenser 2 are interchanged. At this time, evaporator 1 acts as a heating condenser. The gaseous refrigerant that absorbs heat from the outside enters evaporator 1 and condenses into liquid and releases heat, heating the air passing through. The heated air is blown into the room to achieve heating. After the liquid refrigerant flows out of evaporator 1, it is compressed into a high-temperature and high-pressure state by compressor 3 and enters condenser 2. At this time, condenser 2 located indoors acts as a heating evaporator, absorbing the heat of the indoor air and vaporizing the liquid refrigerant into a gaseous state. After the air temperature is lowered, it is discharged to the outside. The gaseous refrigerant then enters compressor 3 to start a new heating cycle, thereby transferring outdoor heat to the room and raising the indoor temperature.

[0212] Furthermore, under cooling or heating conditions, the method for obtaining the cooling evaporation temperature T1 and the heating condensation temperature T2 is as follows: an intake pressure sensor is installed on the evaporator 1 side. Based on the principles of physics, when the type of refrigerant is known, there is a specific corresponding relationship between pressure and temperature. Using this relationship, the corresponding temperature can be converted by measuring the pressure value. Therefore, there is no need to separately set up sensors for measuring the cooling evaporation temperature T1 and the heating condensation temperature T2.

[0213] Combination Figure 5 In the monitoring method flow shown, when performing the dirty and blocked monitoring operation, the control unit 100 obtains the current continuous running time t of the equipment, and determines whether the current continuous running time is greater than the first time threshold t1:

[0214] If not, return to continue monitoring the continuous operation time t of the device; if so, determine whether the device operation mode is cooling mode or heating mode:

[0215] If the judgment result is cooling mode, the control unit 100 obtains the current operating frequency f of the compressor in the air conditioner, and calculates the dirty blockage alarm frequency f0 of the compressor according to the inlet air temperature T and the set dirty blockage percentage η, and further judges whether the current operating frequency f is greater than the dirty blockage alarm frequency f0:

[0216] If not, enter the timing alarm stage; if so, calculate the dirty blockage warning frequency f1 of the compressor according to the inlet air temperature T and the set dirty blockage percentage η, and determine whether the current operating frequency f is less than or equal to the sum of the dirty blockage warning frequency f1 and a constant term, where the constant term represents the set fault tolerance interval:

[0217] If not, continue to monitor the operating frequency of the compressor 3 in real time; if so, according to the pre-set data sampling period, use the above-mentioned suction pressure sensor to calculate and obtain the temperature T1 when the liquid refrigerant in the evaporator 1 absorbs heat and evaporates into gas, measure the refrigerant temperature T3 output from the outlet of the evaporator 1 through the first sensor 1, obtain the actual outlet air temperature T6 through the third sensor 30, and set the ideal outlet air temperature T7 at the remote control end.

[0218] Based on the obtained T1 and T3, the control unit 100 calculates the superheat δ1 of the refrigerant = (T3-T1), and determines whether the superheat δ1 is less than or equal to the superheat threshold T9: if not, continue to monitor the operating frequency of the compressor 3 in real time; if so, determine whether the temperature difference between the ideal outlet air temperature T7 and the actual outlet air temperature T6 is greater than or equal to the temperature deviation threshold T10:

[0219] If not, continue to monitor the operating frequency of the compressor 3 in real time; if so, enter the timing alarm stage, and the control unit 100 obtains the timing time tj , using the data sampling period t s Update the time t j , get the updated time t j * =t j +t s .

[0220] The control unit 100 continues to determine the time t j * Is it greater than or equal to the set system running time threshold t * : If not, return to continue real-time monitoring of the operating frequency of compressor 3; if so, immediately send a dust filter dirty blockage alarm signal to prompt relevant personnel to take maintenance measures in time.

[0221] If the judgment result is heating mode, the control unit 100 obtains the current operating frequency f of the compressor in the air conditioner, and calculates the dirty blockage alarm frequency f0 of the compressor according to the inlet air temperature T and the set dirty blockage percentage η, and further judges whether the current operating frequency f is greater than the dirty blockage alarm frequency f0:

[0222] If not, enter the timing alarm stage; if so, calculate the dirty blockage warning frequency f1 of the compressor according to the inlet air temperature T and the set dirty blockage percentage η, and determine whether the current operating frequency f is less than or equal to the sum of the dirty blockage warning frequency f1 and a constant term, where the constant term represents the set fault tolerance interval:

[0223] If not, continue to monitor the operating frequency of the compressor 3 in real time; if so, according to the pre-set data sampling period, use the above-mentioned suction pressure sensor to calculate and obtain the temperature T2 of the gaseous refrigerant in the condenser after releasing heat and condensing into liquid, measure the refrigerant temperature T4 output from the outlet of the condenser 2 through the second sensor 1, obtain the actual outlet air temperature T6 through the third sensor 30, and set the ideal outlet air temperature T7 at the remote control end.

[0224] Based on the obtained T2 and T4, the subcooling degree δ2 of the refrigerant is calculated as (T2-T4), and it is determined whether the superheat degree δ1 is less than or equal to the product of the superheat threshold value T9 and the heating temperature difference correction coefficient k: if not, the operating frequency of the compressor 3 is continuously monitored in real time; if so, it is determined whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the temperature deviation threshold value T10 updated by the heating temperature difference correction coefficient k:

[0225] If not, continue to monitor the operating frequency of the compressor 3 in real time; if so, enter the timing alarm stage, and the control unit 100 obtains the timing time t j , using the data sampling period t sUpdate the time t j , get the updated time t j * =t j +t s .

[0226] The control unit 100 continues to determine the time t j * Is it greater than or equal to the set system running time threshold t * : If not, return to continue real-time monitoring of the operating frequency of compressor 3; if so, immediately send a dust filter dirty blockage alarm signal to prompt relevant personnel to take maintenance measures in time.

[0227] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0228] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0229] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0230] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A method for detecting dirt and blockage of an air conditioner, characterized in that: The detection method comprises the following steps: Step S1, when the air conditioner is in cooling mode, obtaining the current operating frequency of the compressor in the air conditioner; Step S2, calculating the dirty blockage alarm frequency of the compressor, and determining whether the current operating frequency is greater than the dirty blockage alarm frequency: If not, execute step S4 to enter the timing alarm stage; If yes, calculate the dirty blockage warning frequency of the compressor, and obtain the wind side load size based on the current working frequency and the dirty blockage warning frequency; Step S3, obtaining the superheat, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to a preset data sampling period, analyzing the wind side load size, the superheat, the ideal outlet air temperature and the actual outlet air temperature to obtain a dirty blockage detection result, and then executing step S4; Step S4: Enter the timing alarm phase and obtain the timing time t j , using the data sampling period to update the time t j , get the updated time t j * ; Step S5: Determine the time t j * Is it greater than or equal to the set system running time threshold t * : If not, return to step S1 to continue real-time monitoring of the compressor operating frequency; If so, send a dust filter dirty blockage alarm signal; Wherein, the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions: f2≤f0≤f1≤f3 (1) Among them, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor.

2. The method for detecting dirty or blocked air conditioner according to claim 1, characterized in that: In step S2, based on the current operating frequency and the dirty blockage warning frequency, the method for obtaining the wind side load size is as follows: Determine whether the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and a constant term, where the constant term is used to set a fault tolerance interval: If not, it means that the wind side load size is normal, and the process returns to step S1 to continue to monitor the compressor operating frequency in real time; If so, it means that the wind side load becomes smaller, so the operating frequency of the compressor decreases, and the wind side load size at this time is obtained.

3. The method for detecting dirty or blocked air conditioner according to claim 2, characterized in that: In step S3, the method for analyzing the wind side load size, the superheat, the ideal air outlet temperature and the actual air outlet temperature to obtain the dirty blockage detection result is as follows: Step S31, under the condition that the current operating frequency is less than or equal to the sum of the fouling warning frequency and the constant term, according to the pre-set data sampling period, obtain the temperature T1 when the liquid refrigerant in the evaporator absorbs heat and evaporates into a gaseous state, the refrigerant temperature T3 output at the evaporator outlet, the actual air outlet temperature T6 and the ideal air outlet temperature T7, and calculate the refrigerant superheat δ1=(T3-T1) based on the obtained T1 and T3; Step S32: setting the superheat threshold T9 of the evaporator, and judging whether the superheat δ1 is less than or equal to the superheat threshold T9: If not, return to step S1 to continue real-time monitoring of the compressor operating frequency; If yes, execute step S33; Step S33: setting a temperature deviation threshold value T10, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the temperature deviation threshold value T10: If not, return to step S1 to continue real-time monitoring of the compressor operating frequency; If yes, after obtaining the dirty and blocked detection result, step S4 is executed to enter the timing alarm stage.

4. A method for detecting dirt and blockage of an air conditioner, characterized in that: The detection method comprises the following steps: Step a, when the air conditioner is in heating mode, obtaining the current operating frequency of the compressor in the air conditioner; Step b, calculating the dirty blockage alarm frequency of the compressor, and determining whether the current operating frequency is greater than the dirty blockage alarm frequency: If not, execute step d and enter the timing alarm stage; If yes, calculate the dirty blockage warning frequency of the compressor, and obtain the wind side load size based on the current working frequency and the dirty blockage warning frequency; Step c, obtaining the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to the preset data sampling period, analyzing the wind side load size, the subcooling degree, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirty blockage detection result, then entering the timing alarm stage, and executing step d; Step d: Enter the timing alarm phase and obtain the timing time t j , using the data sampling period to update the time t j , get the updated time t j * ; Step e: Determine the time t j * Is it greater than or equal to the set system running time threshold t * : If not, return to step a and continue to monitor the compressor operating frequency in real time; If so, send a dust filter dirty blockage alarm signal; Wherein, the dirty blockage alarm frequency and the dirty blockage warning frequency both meet the following conditions: f2≤f0≤f1≤f3 (2) Wherein, f0 represents the dirty blockage alarm frequency, f1 represents the dirty blockage warning frequency, f2 represents the minimum operating frequency of the compressor, and f3 represents the maximum operating frequency of the compressor.

5. The method for detecting dirt and blockage of an air conditioner according to claim 4, characterized in that: In step b, based on the current operating frequency and the dirty blockage warning frequency, the method for obtaining the wind side load size is as follows: Determine whether the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and a constant term, where the constant term is used to set a fault tolerance interval: If not, it means that the wind side load size is normal, and the process returns to step a to continue real-time monitoring of the compressor operating frequency; If so, it means that the wind side load becomes smaller, so the operating frequency of the compressor decreases, and the wind side load size at this time is obtained.

6. The method for detecting dirt and blockage of an air conditioner according to claim 5, characterized in that: In step c, the method for analyzing the wind side load size, the supercooling degree, the ideal air outlet temperature and the actual air outlet temperature to obtain the dirty blockage detection result is as follows: Step c1, under the condition that the current operating frequency is less than or equal to the sum of the dirty blockage warning frequency and the constant term, obtain the temperature T2 of the gaseous refrigerant in the condenser after releasing heat and condensing into liquid, the refrigerant temperature T4 output from the condenser outlet, the actual outlet air temperature T6 and the ideal outlet air temperature T7 according to the preset data sampling period, and calculate the refrigerant subcooling δ2=(T2-T4) based on T2 and T4; Step c2, setting the subcooling threshold T9 and the heating temperature difference correction coefficient k of the condenser, adjusting the subcooling threshold T9 by using the heating temperature difference correction coefficient k, obtaining the adjusted subcooling threshold, and judging whether the subcooling δ2 is less than or equal to the adjusted subcooling threshold: If not, return to step a and continue to monitor the compressor operating frequency in real time; If yes, go to step c3; Step c3, setting a temperature deviation threshold T10, adjusting the temperature deviation threshold T10 using the heating temperature difference correction coefficient k, obtaining an adjusted temperature deviation threshold, and determining whether the temperature difference between the ideal air outlet temperature T7 and the actual air outlet temperature T6 is greater than or equal to the adjusted temperature deviation threshold: If not, return to step a and continue to monitor the compressor operating frequency in real time; If yes, after obtaining the dirty and blocked detection result, execute step a and enter the timing alarm stage.

7. The air conditioner dirtiness and blockage detection method according to claim 1 or 4, characterized in that: The method for calculating the compressor's dirty blockage alarm frequency f0 is as follows: Under the environmental condition of relative humidity n1, the inlet air temperature T is obtained, and the ideal heat transfer Q is obtained by data fitting. e1 and the inlet air temperature T: Q e1 =a1T 2 +b1T+c1 (3) Get the rated operating frequency f of the compressor e and rated cooling capacity Q0, based on the rated operating frequency f e , the rated cooling capacity Q0, and the cooling capacity Q1 at the dirty blockage alarm frequency f0 is obtained: Q1=Q0·f0 / f e (4) Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then: V1=V e ·η (5) According to the law of conservation of energy, during the cooling process of the air conditioner, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so: Q e1 ·V1=Q1·V e (6) Arranging formulas (3) to (6) yields: Among them, a1, b1, and c1 are all fitting parameters.

8. The air conditioner dirtiness and blockage detection method according to claim 1 or 4, characterized in that: The method for calculating the compressor's dirty blockage warning frequency f1 is as follows: Under the environmental condition of relative humidity n2, the inlet air temperature T is obtained, and the ideal heat transfer Q is obtained by data fitting. e2 and the inlet air temperature T: <h2 style=";text-align:left;direction:ltr">Q<h2 style=";text-align:left;direction:ltr"> e2 <h2 style=";text-align:left;direction:ltr"> =a2T<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> +b2T+c2 (8) Get the rated operating frequency f of the compressor e and rated cooling capacity Q0, based on the rated operating frequency f e , the rated cooling capacity Q0, and the cooling capacity Q2 at the dirty blockage warning frequency f1 is obtained: Q2=Q0·f1 / f e (9) Let the rated exhaust volume be V e , the exhaust volume after dirty blockage is V1, and the dirty blockage percentage is η, then: V1=V e ·η (10) According to the law of conservation of energy, during the cooling process of the air conditioner, the total amount of heat absorbed and transferred from the indoor environment in the same time is equal, so: Q e2 ·V1=Q2·V e (11) Arranging formulas (8) to (11) yields: Among them, a2, A2, and c2 are all fitting parameters.

9. A method for detecting dirt and blockage of an air conditioner, characterized in that: The detection method comprises the steps of the detection method according to any one of claims 1 to 8, including: Obtain the current continuous running time of the device, and determine whether the current continuous running time is greater than a preset first time threshold: If not, return to continue monitoring the continuous operation time of the device; If yes, determine whether the device is operating in cooling mode or heating mode: If the operation mode of the equipment is the cooling mode, the dust filter is tested for dirtiness and blockage by the detection method according to any one of claims 1 to 3 to obtain a detection result; If the operation mode of the equipment is the heating mode, the dust filter is tested for dirtiness and blockage by the detection method as described in any one of claims 4 to 6 to obtain a detection result.

10. An air conditioner dirt and blockage detection device, characterized in that: It comprises a control unit and a temperature sampling module connected to the control unit, wherein the control unit uses the air conditioner dirtiness and blockage detection method as claimed in claim 9 to detect dirtiness and blockage on the dustproof filter.

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