Air conditioner dirty blockage detection method and device

Abstract

The present application relates to air conditioner detection technical field, especially point to air conditioner dirty block detection method and device, the method includes: in air conditioner is in refrigeration / heat mode, obtain the current working frequency of compressor in air conditioner;Judge current working frequency whether greater than dirty block alarm frequency: if no, enter timing alarm stage;If yes, calculate dirty block early warning frequency, based on the current working frequency and the dirty block early warning frequency, get wind side load size;According to the sampling period obtained refrigerant superheat / cooling degree, ideal and actual outlet air temperature, comprehensive analysis wind side load size, superheat / cooling degree, ideal and actual outlet air temperature get dirty block detection result after entering timing alarm stage;In timing alarm stage, if timing time reaches the set alarm time threshold, send dirty block alarm signal.The present application can reduce material cost, from multiple dimensions comprehensive evaluation air conditioning system operation state, improve the accuracy and reliability of dirty block detection.

Description

Technical Field

[0001] This invention relates to the field of air conditioner testing technology, and in particular to a method and apparatus for detecting dirt and blockage in air conditioners. Background Technology

[0002] In air conditioning systems, dust filters (hereinafter referred to as "filters") play a crucial role. During air conditioner operation, the airflow process is as follows: first, it passes through the filter; then, it undergoes heat exchange through the heat exchanger; finally, the heat-exchanged air is discharged from the vents or ducts and enters the indoor space to achieve cooling or heating functions. However, because the air contains suspended dust and impurities, filters, especially those in air conditioners equipped with fresh air functions, are prone to dust accumulation. Large amounts of dust can clog the air inlet, hindering the flow of air into the heat exchanger and significantly reducing the performance of the air conditioner. Furthermore, numerous bacteria easily adhere to the dust clogging the filter and spread into the indoor environment with the airflow from the air conditioner. Over time, this can have adverse effects on human health.

[0003] Currently, the main methods for testing air conditioner filters are fan power measurement and differential pressure measurement across the filter. The fan power measurement method is based on the principle that a constant-speed fan outputs different power under varying air resistance conditions, thus determining the filter's condition. However, this method is affected by various factors such as air conditions, installation environment, equipment sealing performance, voltage fluctuations, and motor aging, leading to unreliable accuracy and a tendency to generate false alarms in practical applications, thus impacting the user experience. While the differential pressure measurement method offers higher accuracy, it requires two pressure sensors, increasing cost and requiring additional installation space. Summary of the Invention

[0004] To address the problems of high cost, large space occupation, and inaccurate detection due to environmental factors in existing filter clogging detection devices, this invention provides a method and device for detecting air conditioner clogging. The detection method comprises three steps, the first of which includes the following steps:

[0005] Step S1: With the air conditioner in cooling mode, obtain the current operating frequency of the compressor in the air conditioner;

[0006] Step S2: Calculate the compressor's dirt blockage alarm frequency and determine whether the current operating frequency is greater than the dirt blockage alarm frequency.

[0007] If not, proceed to step S4 to enter the timer alarm stage;

[0008] If so, calculate the compressor's dirt blockage warning frequency, and based on the current operating frequency and the dirt blockage warning frequency, obtain the wind-side load size;

[0009] Step S3: Obtain the superheat of the refrigerant, the ideal outlet air temperature and the actual outlet air temperature according to the preset data sampling period. Analyze the air-side load, the superheat, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirt blockage detection results, and then execute step S4.

[0010] Step S4: Enter the timing alarm stage and obtain the timing time t. j Update the time t using the data sampling period. 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 runtime threshold t? * :

[0012] If not, return to step S1 and continue to monitor the compressor operating frequency in real time;

[0013] If so, send an alarm signal for a clogged dust filter;

[0014] The dirt blockage alarm frequency and the dirt blockage early warning frequency both meet the following conditions:

[0015] f2≤f0≤f1≤f3 (1)

[0016] Where f0 represents the dirt blockage alarm frequency, f1 represents the dirt blockage warning frequency, f2 represents the compressor's minimum operating frequency, and f3 represents the compressor's maximum operating frequency.

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

[0018] Determine whether the current operating frequency is less than or equal to the sum of the dirt / clogging warning frequency and a constant term, wherein the constant term is used to set the fault tolerance range:

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

[0020] If so, it means that the wind-side load has decreased, and the compressor's operating frequency has decreased. Obtain the wind-side load size at this time.

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

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

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

[0024] If not, return to step S1 and continue to monitor the compressor operating frequency in real time;

[0025] If so, proceed to step S33;

[0026] Step S33: Set a temperature deviation threshold T10, and 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.

[0027] If not, return to step S1 and continue to monitor the compressor operating frequency in real time;

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

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

[0030] Step a: With the air conditioner in heating mode, obtain the current operating frequency of the compressor in the air conditioner;

[0031] Step b: Calculate the compressor's dirt blockage alarm frequency and determine whether the current operating frequency is greater than the dirt blockage alarm frequency:

[0032] If not, proceed to step d to enter the timer alarm stage;

[0033] If so, calculate the compressor's dirt blockage warning frequency, and based on the current operating frequency and the dirt blockage warning frequency, obtain the wind-side load size;

[0034] Step c: Obtain the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to the preset data sampling period. Analyze the air-side load, the subcooling degree, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirt blockage detection result. Then enter the timing alarm stage and execute step d.

[0035] Step d: Obtain the timing time t jUpdate the time t using the data sampling period. 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 runtime threshold t? * :

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

[0038] If so, send an alarm signal for a clogged dust filter;

[0039] The dirt blockage alarm frequency and the dirt blockage early warning frequency both meet the following conditions:

[0040] f2≤f0≤f1≤f3 (2)

[0041] Where f0 represents the dirt blockage alarm frequency, f1 represents the dirt blockage warning frequency, f2 represents the compressor's minimum operating frequency, and f3 represents the compressor's maximum operating frequency.

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

[0043] Determine whether the current operating frequency is less than or equal to the sum of the dirt / clogging warning frequency and a constant term, wherein the constant term is used to set the fault tolerance range:

[0044] If not, it means that the wind-side load is normal. Return to step a and continue to monitor the compressor operating frequency in real time.

[0045] If so, it means that the wind-side load has decreased, and the compressor's operating frequency has decreased. Obtain the wind-side load size at this time.

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

[0047] Step c1: Under the condition that the current operating frequency is less than or equal to the sum of the dirt blockage warning frequency and the constant term, 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 temperature T4 of the refrigerant output from the condenser outlet, the actual air outlet temperature T6 and the ideal air outlet temperature T7, and calculate the subcooling degree δ2 = (T2 - T4) of the refrigerant.

[0048] Step c2: Set the subcooling threshold T9 of the condenser and the heating temperature difference correction coefficient k. Adjust the subcooling threshold T9 using the heating temperature difference correction coefficient k to obtain the adjusted subcooling threshold. Determine 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's operating frequency in real time;

[0050] If so, proceed to step c3;

[0051] Step c3: Set the temperature deviation threshold T10. Adjust the temperature deviation threshold T10 using the heating temperature difference correction coefficient k to obtain the adjusted temperature deviation threshold. 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 adjusted temperature deviation threshold.

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

[0053] If so, after obtaining the dirt and blockage detection result, proceed to step a and enter the timing alarm stage.

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

[0055] Under environmental conditions with a relative humidity of n1, the inlet air temperature T is obtained, and the ideal heat exchange rate Q is obtained through data fitting. e1 The relationship between the air inlet temperature T and the air inlet temperature T is as follows:

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

[0057] Obtain the compressor's rated operating frequency f e And the rated cooling capacity Q0, based on the rated operating frequency f e The rated cooling capacity Q0 is used to obtain the cooling capacity Q1 at the dirt and blockage alarm frequency f0:

[0058] Q1 = Q0·f0 / f e (4)

[0059] Let the rated exhaust volume be V e If the exhaust volume after the blockage is V1, and the 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 an air conditioner, the total amount of heat absorbed and transferred from the indoor environment within the same time period is equal. Therefore:

[0062] Q e1 ·V1=Q1·V e (6)

[0063] Rearranging formulas (3) to (6), we get:

[0064]

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

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

[0067] Under environmental conditions with a relative humidity of n2, the inlet air temperature T is obtained, and the ideal heat exchange rate Q is obtained through data fitting. e2 The relationship between the air inlet temperature T and the air inlet temperature T is as follows:

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

[0069] Obtain the compressor's rated operating frequency f e And the rated cooling capacity Q0, based on the rated operating frequency f e The rated cooling capacity Q0 is used to obtain the cooling capacity Q2 at the dirt blockage warning frequency f1:

[0070] Q2 = Q0·f1 / f e (9)

[0071] Let the rated exhaust volume be V e If the exhaust volume after the blockage is V1, and the 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 an air conditioner, the total amount of heat absorbed and transferred from the indoor environment within the same time period is equal. Therefore:

[0074] Q e2 ·V1=Q2·V e (11)

[0075] Rearranging formulas (8) to (11), we get:

[0076]

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

[0078] Based on the same inventive concept as the above technical solutions, the present invention also provides a third method for detecting dirt and blockage in air conditioners. This method includes the steps of the first and second detection methods, comprising:

[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 device's continuous uptime;

[0081] If so, determine whether the equipment is in cooling or heating mode:

[0082] If the equipment is operating in cooling mode, the dust filter is tested for dirt and clogging using the corresponding first detection method to obtain the test results.

[0083] If the equipment is operating in heating mode, the dust filter is tested for dirt and clogging using the corresponding second testing method to obtain the test results.

[0084] The present invention also provides an air conditioner dirt and clogging detection device, including a control unit and multiple temperature sampling modules connected to the control unit. The control unit uses the air conditioner dirt and clogging detection method to detect dirt and clogging of the dust filter.

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

[0086] This invention provides a detection method for judging the dirt and blockage status of an air conditioner based on temperature values ​​from multiple measuring points. In existing equipment applications, if the equipment has sufficient reserved temperature sensor interfaces, temperature sensors can be added in a later stage, and the program can be updated to achieve a similar effect to that of a brand-new device using this detection method. This detection method has significant advantages: First, it eliminates the need for a wind pressure sensor required in traditional detection methods, effectively reducing the material cost of the air conditioner and playing a positive role in optimizing the product cost structure; Second, it can significantly reduce misjudgments caused by external interference or internal parameter fluctuations during system operation, improving the accuracy and reliability of detection; Third, it helps ensure that the air conditioning system is always in good operating condition, maintaining stable and efficient performance; Fourth, from the perspective of user experience, through accurate detection and stable operation, it effectively improves the customer's experience in using the air conditioner, enhancing user satisfaction and trust in the product. Attached Figure Description

[0087] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0088] Figure 1 This is a schematic flowchart of an air conditioner dirt and blockage detection method in cooling mode provided in an embodiment of the present invention;

[0089] Figure 2 This is a schematic diagram of a specific process for detecting dirt and blockage in an air conditioner in cooling mode, provided in an embodiment of the present invention.

[0090] Figure 3 This is a schematic flowchart of an air conditioner dirt and blockage detection method in heating mode provided in an embodiment of the present invention;

[0091] Figure 4 This is a schematic diagram of a specific process for detecting dirt and blockage in an air conditioner in heating mode, provided in an embodiment of the present invention.

[0092] Figure 5 This is a schematic flowchart of an air conditioner dirt and blockage detection method provided in an embodiment of the present invention;

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

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

[0095] Explanation of reference numerals in the accompanying drawings: 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 Implementation

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

[0097] Example 1

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

[0099] Step S1: When the air conditioner is in cooling 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.

[0100] Step S2: Calculate the compressor's blockage alarm frequency f0 using the evaporator's inlet air temperature T and the set blockage percentage η through a data fitting process. Then, determine whether the current operating frequency f is greater than the blockage alarm frequency f0.

[0101] If not, it indicates that the system is severely contaminated, and step S4 is executed to enter the timer alarm stage;

[0102] If so, it indicates that the current system may be in a certain degree of clogging and further monitoring is required. At this time, the clogging warning frequency f1 of the compressor is calculated through a data fitting process using the evaporator inlet air temperature T and the set clogging percentage η. Based on the current operating frequency f and the clogging warning frequency f1, the air-side load is obtained.

[0103] Step S3: Obtain the superheat of the refrigerant, the ideal outlet air temperature and the actual outlet air temperature according to the preset data sampling period. Analyze the air-side load, the superheat, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirt blockage detection results, and then execute step S4.

[0104] Step S4: Enter the timing alarm stage and obtain the timing time t. j Update the time t using the data sampling period. 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 runtime threshold t? * :

[0106] If not, return to step S1 and continue to monitor the compressor operating frequency in real time;

[0107] If so, send an alarm signal for a clogged dust filter;

[0108] In order to ensure that the dirt blockage alarm frequency f0 and the dirt blockage warning frequency f1 are within a reasonable range, and to provide a clear frequency definition basis for accurately determining whether the air conditioner is dirty and the different degrees of dirt blockage, both the dirt blockage alarm frequency and the dirt blockage warning frequency meet the following conditions:

[0109] f2≤f0≤f1≤f3 (1)

[0110] In the formula, f0 represents the dirt blockage alarm frequency, f1 represents the dirt blockage warning frequency, f2 represents the compressor's minimum operating frequency, and f3 represents the compressor's maximum operating frequency. Setting the dirt blockage alarm frequency f0 to be less than or equal to the dirt blockage warning frequency f1 can prevent the system from issuing a dirt blockage alarm when there are minor abnormalities.

[0111] As can be seen from the above technical solutions, this invention integrates multiple key parameters for dirt and clogging detection, enabling a comprehensive assessment of the air conditioning system's operating status from multiple dimensions, greatly improving the accuracy and reliability of dirt and clogging detection. The refrigerant superheat reflects the refrigerant's evaporation within the evaporator; the comparison between the ideal and actual outlet air temperature directly reflects the air conditioner's cooling effect; and the air-side load is closely related to the filter's ventilation. By comprehensively analyzing these parameters, it is possible to more accurately determine whether the filter is clogged and the degree of clogging, providing users with more precise maintenance recommendations.

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

[0113] Considering that the compressor frequency will fluctuate to some extent under actual operating conditions, a constant term is introduced to set a tolerance range to prevent misjudgments of abnormal air-side load or filter clogging due to normal frequency fluctuations. This further determines whether the current operating frequency f is less than or equal to the sum of the clogging warning frequency f1 and the constant term.

[0114] If not, it means that the wind-side load is within the normal range. Return to step S1 and continue to monitor the compressor operating frequency in real time.

[0115] If so, it means that the wind-side load has decreased, which in turn causes the compressor's operating frequency to decrease. Obtain the wind-side load size at this time.

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

[0117] Step S31: According to the preset data sampling period, obtain the temperature T1 when the liquid refrigerant absorbs heat and evaporates into a gaseous state in the evaporator, the refrigerant temperature T3 at the evaporator outlet, the actual air outlet temperature T6, and the ideal air outlet temperature T7. Based on the obtained T1 and T3, calculate the superheat of the refrigerant δ1 = (T3 - T1), so as to monitor the state change of the refrigerant in the evaporator in real time.

[0118] Step S32: To initially screen for potential abnormalities in the heat exchanger, a superheat threshold T9 is set for the evaporator, and it is determined 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. Return to step S1 and continue to monitor the operating frequency of the compressor in real time.

[0120] If so, it means that the refrigerant status may have been affected by some factor, and further in-depth judgment is needed. At this time, step S33 should be executed.

[0121] Step S33: Set a temperature deviation threshold T10, and 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.

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

[0123] If so, it indicates a significant difference between the actual airflow and the ideal condition. At this point, the timing alarm phase begins, and the timing time t is acquired. 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 running time threshold t is set. * This threshold must ensure that the following conditions are met simultaneously within the corresponding time period: the current operating frequency f is less than or equal to the sum of the filter clogging 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 clogging is accurately determined, the system should immediately issue an alarm signal.

[0125] Based on practical experience, the system runtime threshold t * A setting of 15 to 30 minutes is recommended. For systems with faster response times, a smaller value within this range can be selected to achieve more timely and accurate detection and alarm of dirt and blockage. The time t is then used to determine the desired response time. j * Is it greater than or equal to the system runtime threshold t? * :

[0126] If not, it indicates that the system has not yet reached a stable operating state, and an accurate diagnosis of dirt blockage 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 so, it means the system has completed stable adjustment, and the dirt / clogging detection result can be obtained based on the current operating data. Once the detection result shows that the dust filter is clogged, the system will immediately send a dust filter clog alarm signal to prompt relevant personnel to take timely maintenance measures.

[0128] Example 2

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

[0130] Step a: When the air conditioner is in heating mode, since the compressor's operating frequency can directly reflect its refrigerant discharge (enthalpy value), the current operating frequency f of the compressor in the air conditioner is obtained.

[0131] Step b: Calculate the compressor's clogging alarm frequency f0 based on the ambient temperature T and the set clogging percentage η, and determine whether the current operating frequency f is greater than the clogging alarm frequency f0.

[0132] If not, it indicates that the system is severely contaminated, and step S4 is executed to enter the timer alarm stage;

[0133] If so, it indicates that the current system may be in a certain degree of clogging and further monitoring is required. At this time, the clogging warning frequency f1 of the compressor is calculated through a data fitting process using the condenser inlet air temperature T and the set clogging percentage η. Based on the current operating frequency f and the clogging warning frequency f1, the air-side load is obtained.

[0134] Step c: Obtain the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to the preset data sampling period, analyze the air-side load, the subcooling degree, the ideal outlet air temperature and the actual outlet air temperature to obtain the dirt blockage detection results, and then execute step d;

[0135] Step d: Enter the timing alarm stage and obtain the timing time t. j Update the time t using the data sampling period. 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 runtime threshold t? * :

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

[0138] If so, send an alarm signal for a clogged dust filter;

[0139] The dirt blockage alarm frequency and the dirt blockage early warning frequency both meet the following conditions:

[0140] f2≤f0≤f1≤f3 (2)

[0141] Where f0 represents the dirt blockage alarm frequency, f1 represents the dirt blockage warning frequency, f2 represents the compressor's minimum operating frequency, and f3 represents the compressor's maximum operating frequency.

[0142] As can be seen from the above technical solutions, this invention integrates multiple key parameters for dirt and clogging detection, enabling a comprehensive assessment of the air conditioning system's operating status from multiple dimensions, greatly improving the accuracy and reliability of dirt and clogging detection. The subcooling of the refrigerant reflects its condensation status in the condenser; the comparison between the ideal and actual outlet air temperature directly reflects the air conditioner's heating effect; and the air-side load is closely related to the filter's ventilation. By comprehensively analyzing these parameters, it is possible to more accurately determine whether the filter is clogged and the degree of clogging, providing users with more precise maintenance recommendations.

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

[0144] Considering that the compressor frequency will fluctuate to some extent under actual operating conditions, a constant term is introduced to set a tolerance range to prevent misjudgments of abnormal air-side load or filter clogging due to normal frequency fluctuations. This is used to further determine whether the current operating frequency f is less than or equal to the sum of the clogging warning frequency f1 and the constant term. The constant term is used to set the tolerance range.

[0145] If not, it means that the wind-side load is normal. Return to step a and continue to monitor the compressor operating frequency in real time.

[0146] If so, it means that the wind-side load has decreased, and the compressor's operating frequency has decreased. Obtain the wind-side load size at this time.

[0147] Further, in step c, under the condition that the current operating frequency is less than or equal to the sum of the dirt blockage warning frequency and the constant term, the method for obtaining the dirt blockage detection result based on the wind-side load magnitude, the subcooling 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 after the gaseous refrigerant in the condenser releases heat and condenses into a liquid state, the temperature T4 of the refrigerant output from the condenser outlet, the actual air outlet temperature T6, and the ideal air outlet temperature T7. Based on the obtained T2 and T4, calculate the subcooling degree of the refrigerant δ2 = (T2 - T4), so as to monitor the state change of the refrigerant in the condenser in real time.

[0149] Step c2: To initially screen for potential anomalies in the heat exchanger, a subcooling threshold T9 needs to be set for the condenser. Since environmental factors are more significant during heating, a heating temperature difference correction coefficient k also needs to be set. Theoretically, T9 should be set to 0K to indicate that the heat exchanger has no superheat. However, temperature sensors are easily affected by ambient environmental factors, leading to measurement deviations; furthermore, if the sensor's accuracy is poor, the subcooling measurement value will fluctuate around 0K. Therefore, T9 is appropriately increased to 1K to eliminate the influence of system errors. The subcooling threshold T9 is adjusted using the heating temperature difference correction coefficient k, resulting in the adjusted subcooling threshold = k × T9. It is then 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. Return to step a and continue to monitor the compressor operating frequency in real time.

[0151] If so, it means that the refrigerant state may have been affected by some factor, and further in-depth judgment is needed. At this time, step c3 should be executed.

[0152] Step c3: Set the temperature deviation threshold T10. Adjust the temperature deviation threshold T10 using the heating temperature difference correction coefficient k to obtain the adjusted temperature deviation threshold = k × T10. 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 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 operating relatively normally. Return to step a and continue to monitor the compressor operating frequency in real time.

[0154] If so, it indicates a significant difference between the actual airflow and the ideal condition. At this point, the timing alarm phase begins, and the timing time t is acquired. 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 runtime threshold t is set. * This threshold must ensure that the following conditions are met simultaneously within the corresponding time period: the current operating frequency f is less than or equal to the sum of the filter clogging warning frequency f1 and the constant term; the refrigerant subcooling δ2 is less than or equal to the adjusted subcooling 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 clogged, the system should immediately issue an alarm signal.

[0156] Based on practical experience, the system runtime threshold t * A setting of 15 to 30 minutes is recommended. For systems with faster response times, a smaller value within this range can be selected to achieve more timely and accurate detection and alarm of dirt and blockage. The time t is then used to determine the desired response time. j * Is it greater than or equal to the system runtime threshold t? * :

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

[0158] If so, obtain the dirt and clogging detection result and send a dirt and clogging alarm signal for the dust filter.

[0159] Furthermore, Table 1 is the enthalpy difference table for cooling air, calculated under constant relative humidity, recording data such as wet-bulb temperature, water content, density, relative humidity, dew point temperature, enthalpy value, and enthalpy difference at different dry-bulb temperatures. Table 2 is the enthalpy difference table for heating air, calculated under a constant water content of 1 g / kg, similarly recording data such as humidity, density, dew point temperature, enthalpy value, and enthalpy difference 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 Enthalpy Difference of Refrigerated Air

[0161]

[0162] Table 2 Enthalpy Difference of Heating Air

[0163]

[0164] Comparing the enthalpy difference data in Tables 1 and 2, it was found that when the temperature difference is the same, the heating enthalpy difference is approximately 3.5 times that of the cooling enthalpy difference. This means that, under the condition of absorbing or releasing the same amount of energy, the temperature change during the heating process is 3.5 times that during the cooling process. However, the moisture content in the air will affect this ratio; in environments with high humidity, this ratio will decrease, even down to about 3 times. Considering the above factors, the range of the heating temperature difference correction coefficient k is determined to be between 2.4 and 3.5. In practical applications, an appropriate value of k should be flexibly selected based on the specific usage environment, sensor calibration accuracy, and other actual conditions.

[0165] Taking a common household wall-mounted air conditioner as an example, when the indoor unit's air intake parameters are 27 / 19.5℃, under the condition of maintaining constant relative humidity and air pressure, by consulting the air enthalpy data at different temperatures, it is calculated that the enthalpy difference change is approximately 83% of that at 35 / 28℃ when the temperature changes by the same amount. 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 a fresh air conditioning unit in Shenzhen, the meteorological parameters used are 33 / 27.9℃ (constant relative humidity). By consulting air enthalpy data under the same constant relative humidity and pressure conditions, it can be seen that the enthalpy difference change under the same temperature variation is approximately 68% of that at 35 / 28℃. According to the calculation method above, the k value at this time is k = 3.5 × 68% = 2.4. This method can also be used to correct the k value for other types of air conditioning equipment.

[0167] Example 3

[0168] Based on the same inventive concept as the above technical solutions, this invention also provides a third method for detecting dirt and blockage in air conditioners, wherein the detection method includes the steps of the first and second detection methods. See also Figure 5 As shown, the third method for detecting dirt and blockage in air conditioners includes:

[0169] Since the compressor requires a certain amount of time to stabilize, considering 3-5 minutes for a household system, the first time threshold is set to 5 minutes. Once the system stabilizes, the judgment loop begins to avoid false alarms due to system instability. The current continuous operating time t of the device is obtained, and it is determined whether the current continuous operating time is greater than the first time threshold t1.

[0170] If not, return to continue monitoring the device's continuous uptime t;

[0171] If so, determine whether the equipment is in cooling or heating mode:

[0172] If the equipment is in cooling mode, the dust filter is tested for dirt and clogging using the detection method in the corresponding embodiment 1, and the test results are obtained. The implementation process is the same as the implementation method described in embodiment 1, and will not be repeated here.

[0173] If the equipment is in heating mode, the dust filter is tested for dirt and clogging using the detection method described in Example 2. The detection results are obtained, and the implementation process is the same as that described in Example 2, so it will not be repeated here.

[0174] Furthermore, in Examples 1 to 3, the enthalpy difference varied depending on the outdoor environment, when the air conditioner treated the air to the target temperature of 12°C and the relative humidity of 95%. Given that the setting of the dirt / clogging alarm frequency f0 should favor more severe conditions that are more likely to trigger an alarm, to ensure consistency in calculation conditions, a relative humidity of 35% (relatively dry environmental humidity conditions) was used for all relevant calculations. Table 3 provides some calculation data for reference.

[0175] Table 3. Enthalpy Difference of Air at 35% Relative Humidity

[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 value 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 dirt blockage alarm frequency f0 is as follows:

[0178] Under specific environmental conditions with a relative humidity of n1 = 35%, the inlet air temperature T was collected (in cooling mode, this is the inlet air temperature of the evaporator; in heating mode, it is the inlet air temperature of the condenser). Subsequently, based on a constant mass flow rate, the ideal heat exchange rate Q was obtained using a data fitting method. e1 The functional relationship between the air temperature and the inlet air temperature T is as follows:

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

[0180] Assuming the compressor operates at its rated frequency f e =60Hz operates under rated summer conditions, with a dry-bulb temperature of 35℃, a wet-bulb temperature of 28℃, an enthalpy difference of 56.34kJ / kg, and an air density of 1.131kg / m³. 3 At this time, the corresponding rated cooling capacity Q0 = 64.44 kJ / m³ 3 .

[0181] Because the compressor operates at low frequencies, its speed is directly proportional to its displacement. Furthermore, under the same environmental parameters and without exceeding the heat exchanger's capacity, the displacement is directly proportional to the air conditioner's cooling or heating capacity. Simultaneously, under normal conditions with moderate load, the compressor speed is directly proportional to the air conditioner's cooling or heating capacity. Therefore, based on the aforementioned rated operating frequency f... e And the rated cooling capacity Q0, the cooling capacity Q1 at the dirt and blockage alarm frequency f0 is obtained:

[0182]

[0183] During the operation of an air conditioning system, if the filter becomes clogged or dirty, it will cause changes in airflow. Let the rated exhaust airflow be V. e If the exhaust volume after the blockage is V1, and the blockage percentage is η, then:

[0184] V1 = V e ·η (5)

[0185] According to the law of conservation of energy, in the cooling process of an air conditioner with the same compressor frequency and evaporation temperature (ignoring the minimal sensible heat exchange portion), regardless of whether there is dirt or blockage, the total amount of heat absorbed and transferred from the indoor environment in the same amount of time is equal. Therefore:

[0186] Q e1 ·V1=Q1·V e (6)

[0187] Rearranging formulas (3) to (6), we get:

[0188]

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

[0190] Furthermore, in Examples 1 to 3, the enthalpy difference of the air conditioning system varies depending on the outdoor environmental conditions when it processes the air to the target temperature (12°C) and the relative humidity reaches 95%. Since ordinary air conditioning equipment typically does not have the function of measuring outdoor wet-bulb temperature, to ensure consistency and feasibility of the calculations, a common relative humidity of 60% is used for the relevant calculations. Table 4 provides some calculation data for reference.

[0191] Table 4. Enthalpy Difference of Air at 60% Relative Humidity

[0192]

[0193]

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

[0195] Under specific environmental conditions with a relative humidity of n² = 60%, the inlet air temperature T was collected (in cooling mode, this is the inlet air temperature of the evaporator; in heating mode, it is the inlet air temperature of the condenser). Subsequently, based on a constant mass flow rate, the ideal heat exchange rate Q was obtained using a data fitting method. e2 The functional relationship between the air temperature and the inlet air temperature T is as follows:

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

[0197] Assuming the compressor operates at its rated frequency f e =60Hz operates under rated summer conditions, with a dry-bulb temperature of 35℃, a wet-bulb temperature of 28℃, an enthalpy difference of 56.34kJ / kg, and an air density of 1.131kg / m³. 3 At this time, the corresponding rated cooling capacity Q0 = 64.44 kJ / m³ 3 Obtain the compressor's rated operating frequency f. e And the rated cooling capacity Q0, based on the rated operating frequency f e The rated cooling capacity Q0 is used to obtain the cooling capacity Q2 at the dirt blockage warning frequency f1:

[0198]

[0199] During the operation of an air conditioning system, if the filter becomes clogged or dirty, it will cause changes in airflow. Let the rated exhaust airflow be V. e If the exhaust volume after the blockage is V1, and the 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 an air conditioner, regardless of whether there is dirt or blockage, the total amount of heat absorbed and transferred from the indoor environment within the same time period is equal. Therefore:

[0202] Q e2 ·V1=Q2·V e (11)

[0203] Rearranging formulas (8) to (11), we get:

[0204]

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

[0206] Example 4

[0207] See Figure 6 and Figure 7 As shown, the present invention also provides an air conditioner dirt blockage detection device, including a control unit 100 and a temperature sampling module 200 connected to the control unit 100. The control unit 100 uses the air conditioner dirt blockage detection method described in Embodiment 3 to detect dirt blockage in 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 located at the refrigerant outlet of the evaporator to acquire the refrigerant temperature T3 in cooling mode; the second sensor 20 is located at the refrigerant outlet of the condenser to acquire the refrigerant temperature T4 in heating mode; the third sensor 30 is placed on 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 location to measure the ambient temperature T.

[0209] The working principle of an air conditioner will be explained next:

[0210] In cooling mode, the liquid refrigerant rapidly vaporizes in the low-pressure environment of evaporator 1, absorbing a large amount of heat from the air through heat exchange, thus cooling the air and achieving a cooling effect. Simultaneously, water vapor in the air liquefies upon cooling and is discharged. The gaseous refrigerant discharged from evaporator 1 is compressed to a high-temperature, high-pressure state by compressor 3 and then transported to condenser 2. Condenser 2 acts as a "heat release end," where the high-temperature, high-pressure gaseous refrigerant releases heat to the external environment. This heat is dissipated outdoors using cooling devices such as fans. After the gaseous refrigerant cools and liquefies, it is depressurized by a throttling valve and re-enters evaporator 1. This cycle repeats continuously, transferring heat from indoors to outdoors.

[0211] In heating mode, the functions of evaporator 1 and condenser 2 are interchanged. Evaporator 1 acts as a heating condenser. Gaseous refrigerant, absorbing heat from the outside, enters evaporator 1, condenses into a liquid state, and releases heat, heating the air flowing through it. The heated air is then blown into the room to achieve heating. Liquid refrigerant flows out of evaporator 1 and is compressed into a high-temperature, high-pressure state by compressor 3 before entering condenser 2. Condenser 2, located indoors, acts as a heating evaporator, absorbing heat from the indoor air, causing the liquid refrigerant to vaporize into a gaseous state. The cooled air is then discharged outdoors, and the gaseous refrigerant re-enters compressor 3, starting a new heating cycle, thereby transferring outdoor heat to the room and raising the indoor temperature.

[0212] Furthermore, under cooling or heating conditions, the cooling evaporation temperature T1 and the heating condensation temperature T2 are obtained as follows: A suction pressure sensor is installed on the evaporator 1 side. Based on the principle of physics, when the type of refrigerant is known, there is a specific correspondence between pressure and temperature. Using this relationship, the corresponding temperature can be calculated by measuring the pressure value. Therefore, there is no need to set up separate sensors to measure the cooling evaporation temperature T1 and the heating condensation temperature T2.

[0213] Combination Figure 5 The monitoring method flow shown describes a process where, during a dirt / clogging monitoring operation, the control unit 100 acquires the current continuous operating time t of the equipment and determines whether the current continuous operating time is greater than the first time threshold t1.

[0214] If not, return to continue monitoring the device's continuous operating time t; if yes, determine whether the device's operating mode is cooling or heating.

[0215] If the determination result is cooling mode, the control unit 100 obtains the current operating frequency f of the compressor in the air conditioner, and calculates the compressor's dirt blockage alarm frequency f0 based on the inlet air temperature T and the set dirt blockage percentage η, and further determines whether the current operating frequency f is greater than the dirt blockage alarm frequency f0:

[0216] If not, proceed to the timing alarm stage; if yes, calculate the compressor's blockage warning frequency f1 based on the intake air temperature T and the set blockage percentage η, and determine whether the current operating frequency f is less than or equal to the sum of the blockage warning frequency f1 and a constant term, where the constant term represents the set fault tolerance range.

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

[0218] Based on the acquired T1 and T3, the control unit 100 calculates the superheat of the refrigerant δ1 = (T3 - T1), and determines whether the superheat δ1 is less than or equal to the superheat threshold T9. If not, it continues to monitor the operating frequency of the compressor 3 in real time. If yes, it determines 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 real-time monitoring of the operating frequency of compressor 3; if yes, enter the timing alarm stage, and the control unit 100 acquires the timing time t.j 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 runtime threshold t? * If not, return to continue real-time monitoring of the operating frequency of compressor 3; if yes, immediately send an alarm signal for dust filter clogging to prompt relevant personnel to take timely maintenance measures.

[0221] If the determination result is heating mode, the control unit 100 obtains the current operating frequency f of the compressor in the air conditioner, and calculates the compressor's dirt blockage alarm frequency f0 based on the inlet air temperature T and the set dirt blockage percentage η, and further determines whether the current operating frequency f is greater than the dirt blockage alarm frequency f0:

[0222] If not, proceed to the timing alarm stage; if yes, calculate the compressor's blockage warning frequency f1 based on the intake air temperature T and the set blockage percentage η, and determine whether the current operating frequency f is less than or equal to the sum of the blockage warning frequency f1 and a constant term, where the constant term represents the set fault tolerance range.

[0223] If not, continuously monitor the operating frequency of compressor 3 in real time; if so, according to the preset 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 state, measure the refrigerant temperature T4 output from the outlet of condenser 2 through the second sensor 1, obtain the actual air outlet temperature T6 through the third sensor 30, and set the ideal air outlet temperature T7 at the remote control terminal.

[0224] Based on the obtained T2 and T4, calculate the subcooling degree of the refrigerant δ2 = (T2 - T4), and determine whether the superheat degree δ1 is less than or equal to the product of the superheat threshold T9 and the heating temperature difference correction coefficient k: if not, continue to monitor the operating frequency of compressor 3 in real time; if yes, 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 updated using the heating temperature difference correction coefficient k.

[0225] If not, continue real-time monitoring of the operating frequency of compressor 3; if yes, enter the timing alarm stage, and the control unit 100 acquires 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 runtime threshold t? * If not, return to continue real-time monitoring of the operating frequency of compressor 3; if yes, immediately send an alarm signal for dust filter clogging to prompt relevant personnel to take timely maintenance measures.

[0227] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0228] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0229] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0230] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for detecting dirt and blockage in an air conditioner, characterized in that, The detection method includes the following steps: Step S1: With the air conditioner in cooling mode, obtain the current operating frequency of the compressor in the air conditioner; Step S2: Calculate the compressor's dirt blockage alarm frequency and determine whether the current operating frequency is greater than the dirt blockage alarm frequency. If not, proceed to step S4 to enter the timer alarm stage; If so, calculate the compressor's dirt blockage warning frequency, and determine whether the current operating frequency is less than or equal to the sum of the dirt blockage warning frequency and a constant term, where the constant term is used to set the fault tolerance interval. If not, it means that the wind-side load is normal. Return to step S1 and continue to monitor the compressor operating frequency in real time. If so, it means that the wind-side load has decreased, and the compressor's operating frequency has decreased. Proceed to step S3. Step S3: Obtain the superheat of the refrigerant, the ideal outlet air temperature, and the actual outlet air temperature according to the preset data sampling cycle. Analyze the superheat, the ideal outlet air temperature, and the actual outlet air temperature to obtain the dirt blockage detection result, and then proceed to step S4. Step S4: Enter the timing alarm stage and obtain the timing time. t j Update the time using the data sampling period. 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 runtime threshold? t * : If not, return to step S1 and continue to monitor the compressor operating frequency in real time; If so, send an alarm signal for a clogged dust filter; The dirt blockage alarm frequency and the dirt blockage early warning frequency both meet the following conditions: (1) in, Indicates the frequency of dirt and blockage alarms. Indicates the frequency of dirt and congestion warnings. This indicates the compressor's minimum operating frequency. Indicates the compressor's maximum operating frequency; In step S2, the frequency of compressor dirt blockage alarm is calculated. The method is as follows: Under environmental conditions with a relative humidity of n1, the inlet air temperature T is obtained, and the ideal heat exchange rate is obtained through data fitting. The relationship between the air inlet temperature T and the air inlet temperature T is as follows: (2) Obtain the compressor's rated operating frequency and rated cooling capacity Based on the rated operating frequency The rated cooling capacity The frequency of the dirt blockage alarm is obtained. cooling capacity : (3) Let the rated exhaust volume be The exhaust volume after the blockage is The percentage of dirt blockage is Then we have: (4) According to the law of conservation of energy, during the cooling process of an air conditioner, the total amount of heat absorbed and transferred from the indoor environment within the same time period is equal. Therefore: (5) Rearranging formulas (2) to (5), we get: (6) in, 、 、 All are fitted parameters; In step S2, the frequency of compressor dirt blockage warning is calculated. The method is as follows: Under environmental conditions with a relative humidity of n2, the inlet air temperature T is obtained, and the ideal heat exchange rate is obtained through data fitting. The relationship between the air inlet temperature T and the air inlet temperature T is as follows: (7) Obtain the compressor's rated operating frequency and rated cooling capacity Based on the rated operating frequency The rated cooling capacity The frequency of the dirt blockage warning was obtained. cooling capacity : (8) Let the rated exhaust volume be The exhaust volume after the blockage is The percentage of dirt blockage is Then we have: (9) According to the law of conservation of energy, during the cooling process of an air conditioner, the total amount of heat absorbed and transferred from the indoor environment within the same time period is equal. Therefore: (10) Rearranging formulas (7) to (10), we get: (11) in, 、 、 All are fitted parameters; In step S3, the method for analyzing the superheat, the ideal outlet air temperature, and the actual outlet air temperature to obtain the dirt 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 dirt blockage warning frequency and the constant term, according to the preset 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 from the evaporator outlet, the actual air outlet temperature T6, and the ideal air outlet temperature T7. Based on the obtained T1 and T3, calculate the superheat of the refrigerant δ1=(T3-T1). Step S32: Set the superheat threshold T9 of the evaporator, and determine whether the superheat δ1 is less than or equal to the superheat threshold T9: If not, return to step S1 and continue to monitor the compressor operating frequency in real time; If so, proceed to step S33; Step S33: Set a temperature deviation threshold T10, and 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. If not, return to step S1 and continue to monitor the compressor operating frequency in real time; If so, after obtaining the dirt and blockage detection result, proceed to step S4 to enter the timing alarm stage.

2. A method for detecting dirt and blockage in an air conditioner, characterized in that, The detection method includes the following steps: Step a: With the air conditioner in heating mode, obtain the current operating frequency of the compressor in the air conditioner; Step b: Calculate the compressor's dirt blockage alarm frequency and determine whether the current operating frequency is greater than the dirt blockage alarm frequency: If not, proceed to step d to enter the timer alarm stage; If so, calculate the compressor's dirt blockage warning frequency, and determine whether the current operating frequency is less than or equal to the sum of the dirt blockage warning frequency and a constant term, where the constant term is used to set the fault tolerance interval. If not, it means that the wind-side load is normal. Return to step a and continue to monitor the compressor operating frequency in real time. If so, it means the wind-side load has decreased, so the compressor's operating frequency has decreased, and step c should be executed. Step c: Obtain the subcooling degree, ideal outlet air temperature and actual outlet air temperature of the refrigerant according to the preset data sampling period, analyze the subcooling degree, ideal outlet air temperature and actual outlet air temperature to obtain the dirt blockage detection result, and then enter the timing alarm stage and execute step d; Step d: Enter the timing alarm stage and obtain the timing time. t j Update the time using the data sampling period. 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 runtime threshold? t * : If not, return to step a and continue to monitor the compressor's operating frequency in real time; If so, send an alarm signal for a clogged dust filter; The dirt blockage alarm frequency and the dirt blockage early warning frequency both meet the following conditions: (12) in, Indicates the frequency of dirt and blockage alarms. Indicates the frequency of dirt and congestion warnings. This indicates the compressor's minimum operating frequency. Indicates the compressor's maximum operating frequency; In step b, the frequency of compressor dirt blockage alarm is calculated. The method is as follows: Under environmental conditions with a relative humidity of n1, the inlet air temperature T is obtained, and the ideal heat exchange rate is obtained through data fitting. The relationship between the air inlet temperature T and the air inlet temperature T is as follows: (13) Obtain the compressor's rated operating frequency and rated cooling capacity Based on the rated operating frequency The rated cooling capacity The frequency of the dirt blockage alarm is obtained. cooling capacity : (14) Let the rated exhaust volume be The exhaust volume after the blockage is The percentage of dirt blockage is Then we have: (15) According to the law of conservation of energy, during the heating process of an air conditioner, the total amount of heat transferred to the indoor environment within the same time period is equal. Therefore: (16) Rearranging formulas (13) to (16), we get: (17) in, 、 、 All are fitted parameters; In step b, the frequency of compressor dirt blockage warning is calculated. The method is as follows: Under environmental conditions with a relative humidity of n2, the inlet air temperature T is obtained, and the ideal heat exchange rate is obtained through data fitting. The relationship between the air inlet temperature T and the air inlet temperature T is as follows: (18) Obtain the compressor's rated operating frequency and rated cooling capacity Based on the rated operating frequency The rated cooling capacity The frequency of the dirt blockage warning was obtained. cooling capacity : (19) Let the rated exhaust volume be The exhaust volume after the blockage is The percentage of dirt blockage is Then we have: (20) According to the law of conservation of energy, during the heating process of an air conditioner, the total amount of heat transferred to the indoor environment within the same time period is equal. Therefore: (21) Rearranging formulas (18) to (21), we get: (22) in, 、 、 All are fitted parameters; In step c, the method for analyzing the subcooling, the ideal outlet air temperature, and the actual outlet air temperature to obtain the dirt 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 dirt blockage warning frequency and the constant term, 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 temperature T4 of the refrigerant output from the condenser outlet, the actual air outlet temperature T6 and the ideal air outlet temperature T7, and calculate the subcooling degree of the refrigerant δ2=(T2-T4) based on T2 and T4. Step c2: Set the subcooling threshold T9 of the condenser and the heating temperature difference correction coefficient k. Adjust the subcooling threshold T9 using the heating temperature difference correction coefficient k to obtain the adjusted subcooling threshold. Determine 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's operating frequency in real time; If so, proceed to step c3; Step c3: Set the temperature deviation threshold T10. Adjust the temperature deviation threshold T10 using the heating temperature difference correction coefficient k to obtain the adjusted temperature deviation threshold. 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 adjusted temperature deviation threshold. If not, return to step a and continue to monitor the compressor's operating frequency in real time; If so, after obtaining the dirt and blockage detection result, proceed to step a and enter the timing alarm stage.

3. A method for detecting dirt and blockage in an air conditioner, characterized in that, The detection method includes the steps of the detection method as described in claim 1 or claim 2, 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 device's continuous uptime; If so, determine whether the equipment is in cooling or heating mode: If the equipment is in cooling mode, the dust filter is tested for dirt and clogging using the detection method described in claim 1 to obtain the test results; If the equipment is in heating mode, the dust filter is tested for dirt and clogging using the detection method described in claim 2, and the test results are obtained.

4. An air conditioner dirt and blockage detection device, characterized in that, The device includes a control unit and a temperature sampling module connected to the control unit. The control unit uses the air conditioner dirt clogging detection method as described in claim 3 to detect dirt clogging on the dust filter.

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