An air conditioner self-cleaning method, electronic equipment and air conditioner

Abstract

The application provides an air conditioner self-cleaning method, electronic equipment and an air conditioner. The method can accurately control the triggering time of the defrosting program by dynamically judging the frosting state of the heat exchanger in the heating mode, thereby improving the effectiveness of defrosting. The method avoids the problem of poor cleaning effect caused by the inflexible defrosting control method. When the first condition and the second condition of the heat exchanger both meet the set condition, the preset defrosting program is timely called, and after the defrosting is completed, the dirt is blown away by reversing the fan, thereby greatly reducing the accumulation of dust and dirt on the surface of the heat exchanger. The method significantly improves the accuracy and effectiveness of the air conditioner self-cleaning process by combining multi-level judgment and control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioners, and in particular to an air conditioner self-cleaning method, an electronic device and an air conditioner. BACKGROUND

[0002] Self-cleaning of an air conditioner refers to cleaning key components such as heat exchangers and filters inside and outside the air conditioning equipment through automatic programs and technical means during normal operation to reduce the accumulation of dust, dirt and impurities.

[0003] In the application scenario of air conditioner self-cleaning, there is a technical problem that the self-cleaning effect is poor due to the inflexible defrosting control method. SUMMARY

[0004] The present application aims to overcome the above technical deficiencies and provide an air conditioner self-cleaning method, an electronic device and an air conditioner to solve the technical problem of poor self-cleaning effect due to the inflexible defrosting control method in related technologies.

[0005] To achieve the above technical purpose, the present application adopts the following technical solutions:

[0006] In a first aspect, the present application provides an air conditioner self-cleaning method, which comprises:

[0007] In response to an instruction for air conditioner self-cleaning, operating the air conditioner in a heating mode to at least reduce the surface temperature of an outdoor unit heat exchanger;

[0008] In the case where the air conditioner has not entered defrosting is not detected, and the air conditioner has been running in a heating mode for a preset time, determining whether the outdoor unit heat exchanger meets the first condition and the second condition at the same time; wherein the first condition is a condition for determining whether the temperature difference of the refrigerant in a certain time window meets a temperature threshold, and the second condition is a condition for determining whether the current refrigerant can cause the outdoor unit heat exchanger to frost; wherein the refrigerant is the refrigerant in the outdoor unit heat exchanger, and the certain time window is within the preset time;

[0009] In the case where the first condition and the second condition are met at the same time, calling a preset defrosting program to defrost the outdoor unit of the air conditioner;

[0010] After the defrosting program ends, controlling the fan of the air conditioner outdoor unit to perform reverse rotation to at least blow off the dirt-carrying melt water on the outdoor unit heat exchanger.

[0011] In a second aspect, the present application provides an electronic device, comprising: a memory, and one or more processors connected with the memory in communication; the memory has stored instructions executable by the one or more processors, and the instructions are executed by the one or more processors to cause the one or more processors to implement the method described above.

[0012] In a third aspect, the present application provides an air conditioner which adopts the method described above, or comprises the electronic device described above.

[0013] Advantages:

[0014] The present application can accurately control the triggering time of the defrosting program by dynamically judging the frosting state of the heat exchanger in the heating mode, thereby improving the effectiveness of defrosting. The method avoids the problem of poor cleaning effect caused by the inflexible defrosting control method, timely calls the preset defrosting program when the first condition and the second condition of the heat exchanger both meet the set condition, and blows away dirt after defrosting through reversing the fan, thereby greatly reducing the accumulation of dust and dirt on the surface of the heat exchanger. This method significantly improves the accuracy and effectiveness of the self-cleaning process of the air conditioner by combining multi-level judgment and control. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a flowchart of an air conditioner self-cleaning method provided by an embodiment of the present application;

[0016] Figure 2 is a flowchart of an air conditioner self-cleaning method provided by an embodiment of the present application;

[0017] Figure 3 is a flowchart of an air conditioner self-cleaning method provided by an embodiment of the present application;

[0018] Figure 4 is a block diagram of an electronic device adopted by an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to enable personnel in the technical field to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor should fall within the scope of protection of the present application.

[0020] In the related art, the service life of existing air conditioners is relatively long, and with the increase of the use time, the air inlet side of the air conditioner, such as the heat exchanger, filter screen and the like, will inevitably accumulate a lot of dust, garbage and other sundries. These sundries may at least affect the heat exchange efficiency of the refrigeration system, increase energy consumption, and in severe cases, even trigger system protection, resulting in the air conditioning system unable to operate normally. The indoor unit is located indoors, and there is a filter in front of the heat exchanger, so it is relatively simple to clean, and normal cleaning only needs to remove and clean the filter. The outdoor unit of the air conditioner is located outdoors, and is usually located on the outer wall. In general, only professional personnel can clean it. Even large-capacity air-cooled multi-split units are mostly located outdoors on the roof, etc. Since the outdoor heat exchanger is basically not equipped with a filter, the cleaning device can only be moved to the vicinity of the outdoor unit for cleaning, which is extremely inconvenient. Therefore, a control program is needed that can accurately determine the dirty and clogged condition of the outdoor heat exchanger and perform a certain degree of self-cleaning, thereby reducing or even eliminating the need for manual cleaning. The heat exchanger can be kept in a good heat exchange state, reducing the energy consumption caused by the dirty and clogged heat exchanger, and allowing the refrigeration system to operate within a relatively stable range.

[0021] In a feasible technical solution, the self-cleaning of the outdoor unit of the air conditioner can be achieved through a frosting stage and a defrosting stage. Specifically, in the frosting stage, the air conditioner operates in a heating mode to condense the moisture in the outdoor air in the form of water droplets on the surface of the heat exchanger of the outdoor unit. As the heating mode operates, the surface temperature of the heat exchanger of the outdoor unit further decreases, causing the water droplets on the surface of the heat exchanger to freeze into a frost layer. The frost layer combines with the dust on the surface of the heat exchanger and peels off. In the defrosting stage, the air conditioner operates in a cooling mode, the temperature of the outdoor heat exchanger increases, the frost layer melts, and then is blown off.

[0022] Existing air conditioners usually have a defrosting program, but different manufacturers' defrosting programs have different precision in detecting frost layer. Some defrosting programs have low precision and may not be able to detect thin frost layer, resulting in failure to start the defrosting program in time. In this case, although the surface of the heat exchanger has already frozen, the frost layer is too thin to be detected, affecting the normal cleaning effect of the air conditioner. In some cases, the surface of the heat exchanger may never form a frost layer, causing the defrosting program to fail to trigger. In some technical solutions, if no frost is detected, the heating mode will continue to operate to reduce the surface temperature of the outdoor heat exchanger to promote frosting (the surface of the heat exchanger may have already frozen, but the frost has not been detected by the preset defrosting program). In some cases, no matter how long the air conditioner operates, it cannot form frost. For example, the air humidity is too low, the air conditioner operates at a low load, or the fan speed is too low, causing the water vapor to fail to effectively contact and condense on the surface of the heat exchanger. Therefore, this control method will cause the air conditioner to be in an invalid heating state for a long time, increasing energy consumption and causing equipment wear and tear, but still failing to trigger the defrosting program. Accordingly, it will also affect the self-cleaning effect of the air conditioner.

[0023] In some technical solutions, a timed defrosting strategy can be adopted, that is, a defrosting program is forcibly triggered once within a set time interval regardless of whether frost is detected. However, this can cause unnecessary defrosting in the absence of frost, wasting energy. More importantly, the working conditions on site are complex, and it is difficult to accurately set the time interval. For example, in one case, the outdoor unit has been running for a period of time without frosting but will soon frost, but the timed defrosting strategy causes it to be unable to frost all the time, and can also cause the condensation water on the surface of the heat exchanger to be evaporated. It can be understood that the evaporation of condensation water will affect the blowing effect of the outdoor unit fan, and thus affect the self-cleaning effect of the air conditioner. In some technical solutions, the user is prompted to manually set the air conditioner to enter the defrosting mode, especially when the system cannot automatically detect frosting. However, this requires the user to actively intervene and cannot achieve true self-cleaning.

[0024] Therefore, in summary, in the application scenario of air conditioner self-cleaning, there is a technical problem that the self-cleaning effect is not good due to the inflexible defrosting control method.

[0025] As shown in Figure 1 The present embodiment provides an air conditioner self-cleaning method, which can include:

[0026] Step S102: in response to the instruction of air conditioner self-cleaning, operating the air conditioner in a heating mode to at least reduce the surface temperature of the outdoor unit heat exchanger.

[0027] In the heating mode, the refrigerant absorbs heat and evaporates in the heat exchanger of the outdoor unit, causing the surface temperature of the heat exchanger to gradually decrease. When the temperature decreases to near or below the dew point, the water vapor in the air begins to condense on the surface of the heat exchanger, forming condensation water. If the temperature continues to drop below 0°C, these condensation waters will further frost. Frosting is a prerequisite for defrosting. By reducing the surface temperature of the heat exchanger in the heating mode, frost can be formed on the surface of the heat exchanger under appropriate environmental conditions (such as lower ambient temperature and higher humidity). This provides a basis for subsequent defrosting operation. By operating the air conditioner in the heating mode to make the heat exchanger surface frost and enter the defrosting program, the dust and dirt attached to the surface of the heat exchanger can be effectively peeled off. After defrosting is completed, the fan is reversed to blow off these dirt together with the melted water, thereby improving the self-cleaning effect of the air conditioner and maintaining the operating efficiency and performance of the equipment.

[0028] In the present embodiment, operating the air conditioner in the heating mode can not only reduce the surface temperature of the outdoor unit heat exchanger, but also reduce the outdoor unit fan and metal components, connecting pipes, and the shell of the outdoor unit, etc. It can be understood that when the air conditioner is operated in the heating mode, the outdoor unit fan can be in a state of forward rotation.

[0029] In the embodiment, the self-cleaning instruction of the air conditioner can be a self-cleaning instruction manually triggered by a user. Specifically, the user manually sends the self-cleaning instruction through an air conditioner remote controller, a smartphone or other terminal device. After receiving the instruction, the controller of the air conditioner first confirms whether the air conditioner is currently in an idle state or a mode suitable for performing a self-cleaning operation (such as a non-cooling mode). After confirming that the self-cleaning condition is met, the controller can operate the air conditioner in a heating mode, for example, activates the compressor, adjusts the reversing valve, starts the outdoor unit and indoor unit fan, and the like, so that the air conditioner enters a heating state.

[0030] In the embodiment, the air conditioner is built-in with a dirty blockage identification rule. For example, the sensor can detect the air flow condition, temperature distribution, refrigerant pressure and other parameters of the heat exchanger to automatically determine whether the heat exchanger has a dirty blockage phenomenon. When a dirty blockage is identified, the controller automatically generates and triggers a self-cleaning instruction. The controller automatically executes the self-cleaning instruction, first determines the current operating state of the air conditioner. If the air conditioner is in a state suitable for performing a self-cleaning operation (such as a non-cooling mode), it switches to a heating mode. After switching to the heating mode, the controller controls the compressor, reversing valve, fan and other components to enter a working state.

[0031] In some embodiments, the air conditioner is built-in with a dirty blockage identification rule. When a dirty blockage is detected, the controller generates a self-cleaning request and prepares to notify the user. The controller sends a request notification to the user's terminal device (such as a smartphone or tablet computer). The notification content prompts the user that the air conditioner has detected a dirty blockage condition and asks the user to specify a cleaning time through the terminal device. This cleaning time will be used as the trigger condition for the controller to perform a self-cleaning operation. After receiving the request notification, the user can set a specific cleaning time through the terminal device and send an instruction back to the air conditioner. The instruction contains the cleaning time parameter. After receiving the instruction sent by the user, the controller records the cleaning time set by the user and sets a timing task internally to trigger the self-cleaning operation at the scheduled time. When the scheduled cleaning time arrives, the controller automatically switches the air conditioner to a heating mode. The specific operation includes starting the compressor, adjusting the reversing valve, starting the outdoor unit and indoor unit fan, and the like, to ensure that the air conditioner enters a heating state and the surface temperature of the outdoor unit heat exchanger is reduced to a level suitable for frosting.

[0032] Step S104: In the case that the air conditioner is not detected to enter defrosting, and the air conditioner has accumulated running in the heating mode for a preset time, it is judged whether the outdoor unit heat exchanger meets the first condition and the second condition at the same time; wherein the first condition is a condition for judging whether the temperature difference of the refrigerant in a certain time window meets a temperature threshold, and the second condition is a condition for judging whether the current refrigerant can cause the outdoor unit heat exchanger to frost; wherein the refrigerant is the refrigerant in the outdoor unit heat exchanger, and the certain time window is within the preset time.

[0033] In some cases, the defrosting program of the air conditioner may not accurately detect the formation of frost, especially when the frost is thin, the defrosting program may not be triggered. Therefore, it is necessary to accurately determine whether frost has formed by other means. Therefore, when the air conditioner has been running in the heating mode for a preset time, and the defrosting has not been detected, the heat exchange efficiency of the air conditioner may have been affected by the frost. By judging whether the first condition and the second condition are met, the air conditioner can further confirm whether there is frost. Even if the defrosting program is not triggered, it is considered that the air conditioner has frosted at this time when the first condition and the second condition are met at the same time.

[0034] In the present embodiment, the controller can detect whether the preset defrosting program is running. When the preset defrosting program has been in a running state, it indicates that the air conditioner has entered a defrosting state. Specifically, by monitoring the running state of the air conditioner, especially the starting condition and running state of the preset defrosting program, it can be judged whether the current air conditioner has entered the defrosting state. If it is detected that the air conditioner is executing the defrosting program, it means that the air conditioner has entered the defrosting state. In some embodiments, in addition to detecting whether the preset defrosting program is running to determine whether the air conditioner enters defrosting, the change of system low pressure (saturation temperature of refrigerant) can also be monitored, the temperature of the refrigerant can be monitored, for example, during the defrosting process, the surface temperature of the outdoor unit heat exchanger will gradually rise, which may cause the temperature of the refrigerant to also rise. The change of compressor power can also be detected. In some embodiments, the preset defrosting sensor can also be used to detect whether the air conditioner has entered the defrosting state, for example, some air conditioners are equipped with special defrosting sensors, which directly monitor the frost thickness or the change of heat exchanger surface temperature. When the sensor feedback reaches the preset value, it means that the air conditioner has entered the defrosting state. It can be understood that considering the diversity of the field operation environment, the above methods cannot guarantee to stably and accurately detect whether the air conditioner enters defrosting.

[0035] In this embodiment, the preset time is represented as a period of time during which the air conditioner is operated in the heating mode, to ensure that the surface temperature of the outdoor unit, particularly the heat exchanger, can be sufficiently reduced to meet the frosting condition. The preset time can be flexibly set, such as 1 hour, 1.5 hours, 2 hours, etc., and can be adjusted according to actual working conditions and requirements. It can also be set through experiments under various environmental conditions. Specifically, the preset time is set to ensure that the air conditioner is continuously operated in the heating mode, so that the outdoor unit heat exchanger has sufficient time to reduce the surface temperature. If the air conditioner fails to continuously operate for the preset time, it may indicate that the temperature reduction is not sufficient, and the heat exchanger surface temperature has not reached the level that can frost. The preset time is not a fixed value, but is flexibly set according to specific environmental conditions, the operating condition of the air conditioner, and user requirements, etc. For example, in some cases, 1 hour may be sufficient to make the heat exchanger surface reach the frosting condition, while in other cases, it may take 1.5 hours or 2 hours to achieve the same effect. The presence of the preset time allows the controller to determine whether the air conditioner has been operated for a sufficient period of time to achieve sufficient temperature reduction. If the air conditioner fails to continuously operate for the preset time, it may indicate that the system has not been sufficiently cooled and needs to continue operating to achieve the desired frosting condition.

[0036] In this embodiment, the first condition is a condition for determining whether the temperature difference of the refrigerant in a certain time window meets the temperature threshold, and the certain time window is within the preset time.

[0037] In this embodiment, meeting the temperature threshold can mean being equal to or greater than the temperature threshold.

[0038] In this embodiment, the certain time window can be a time window in the early part of the preset time, for example, in the case of a preset time of 1 hour, the certain time window can be the first 10 minutes (e.g., 10 minutes to 20 minutes) of the hour for measuring and determining the temperature difference of the refrigerant. The certain time window can be a time window in the middle of the preset time, for example, in the case of a preset time of 1 hour, the certain time window can be the middle 10 minutes (e.g., 30 minutes to 40 minutes) of the hour for measuring and determining the temperature difference of the refrigerant. The certain time window can be a time window in the late part of the preset time, for example, in the case of a preset time of 1 hour, the certain time window can be the last 10 minutes (e.g., 50 minutes to 60 minutes) of the hour for measuring and determining the temperature difference of the refrigerant.

[0039] In the present embodiment, the time window can be set to a short period, such as 5 minutes or 10 minutes, for quickly determining the change of the refrigerant temperature. The time window can also be set to a long period, such as 15 minutes or 20 minutes, for more robustly detecting the change trend of the refrigerant temperature.

[0040] In the present embodiment, the first condition can be based on the change of the saturation temperature of the refrigerant, and in a certain time window, it is compared whether the drop value of the saturation temperature reaches or exceeds a temperature threshold (such as ≥ 2℃). The first condition can also be based on the change of the actual temperature of the refrigerant, and in a certain time window, it is compared whether the drop value of the actual temperature reaches or exceeds a temperature threshold. The threshold of the first condition can be set to a fixed value, for example, 2℃. The temperature threshold can also be dynamically adjusted according to different environmental conditions, refrigerant types or system states, and can fluctuate between 1℃ and 5℃.

[0041] In some embodiments, multiple time windows can also be set, such as 10-20 minutes, 30-40 minutes and 50-60 minutes, to detect the change of the refrigerant temperature difference respectively, and the results are combined for comprehensive judgment.

[0042] In the present embodiment, the temperature threshold is a preset temperature difference value, which can be 2℃, 3℃, 5℃, etc. The temperature threshold is determined by experiments.

[0043] In the present embodiment, the second condition is a condition for determining whether the current refrigerant can cause the outdoor unit heat exchanger to frost. It should be noted that the second condition can be to determine whether the refrigerant has the ability to promote the heat exchanger to frost only from the physical properties of the refrigerant itself under the condition of excluding external influencing factors.

[0044] In the present embodiment, in the second condition, the judgment can also be based on the saturation temperature of the refrigerant, for example, it can be determined whether the saturation temperature of the current refrigerant (in the case of a preset time of 1 hour, the current point is 60 minutes) is lower than 0℃. If the saturation temperature is lower than 0℃, it is considered that the refrigerant has the condition to promote the heat exchanger to frost.

[0045] In some embodiments, in the second condition, the judgment can also be based on the actual temperature of the refrigerant. For example, it can be determined whether the actual temperature of the current refrigerant (in the case of a preset time of 1 hour, the current point is 60 minutes) is lower than 0℃. If the actual temperature is lower than 0℃, the refrigerant can cause the heat exchanger surface to frost.

[0046] In some embodiments, in a complex environmental condition, such as a high humidity or high temperature environment, the second condition can also be a judgment of whether the actual temperature of the refrigerant is significantly lower than the ambient temperature. When the actual temperature of the refrigerant is significantly lower than the ambient temperature, it is considered that the refrigerant has the condition to promote the frosting of the heat exchanger.

[0047] In some embodiments, in the second condition, it can also be a judgment based on the heat conduction characteristics of the refrigerant. The heat conduction performance of the refrigerant can change with temperature and pressure changes, especially when it is close to the frosting point, the heat conduction coefficient can decrease. By detecting the change of the heat conduction coefficient of the refrigerant at the current time, it can be judged whether it is close to the frosting condition.

[0048] In some embodiments, the multiple physical properties of the refrigerant (such as temperature, pressure, flow, heat conductivity, etc.) are analyzed to determine whether the current time has the ability to promote the frosting of the heat exchanger.

[0049] In one possible specific embodiment, the first condition can be that the saturation temperature of the refrigerant at the 50th minute - the saturation temperature of the refrigerant at the 60th minute ≥ 2℃ in the case of a preset time of 1 hour. In the heating mode, the saturation temperature of the refrigerant decreases significantly between 50 minutes and 60 minutes. This decrease is usually due to the formation of a layer of frost on the surface of the heat exchanger. The formation of the frost layer reduces the heat exchange efficiency, causing the evaporator temperature to further decrease, resulting in a significant decrease in system low pressure. Therefore, the significant decrease in the saturation temperature of the refrigerant is an important feature of the frosting of the surface of the heat exchanger.

[0050] The second condition can be that the saturation temperature of the refrigerant at the 60th minute < 0℃ in the case of a preset time of 1 hour. The saturation temperature of the refrigerant is lower than 0℃, which means that the temperature of the outdoor unit heat exchanger is very low, which is enough to cause the condensate water on the surface of the heat exchanger to freeze into a frost layer. The low temperature condition is the direct cause of the formation of the frost layer. When the saturation temperature of the refrigerant is lower than 0℃, it means that the temperature of the surface of the heat exchanger has reached or is lower than the frost point temperature, further verifying the existence of the frost layer.

[0051] The above embodiments overcome the precision deficiency of the existing defrosting control method by introducing a double judgment condition based on the saturation temperature of the refrigerant and the temperature drop. This method can dynamically monitor and real-time judge the frosting condition of the heat exchanger within a preset time, thereby avoiding the misjudgment or missed defrosting opportunity that may be caused by the traditional timed defrosting. By triggering the defrosting program in time when the heat exchanger tends to or has already frosted, the embodiments ensure that the heat exchanger can be effectively cleaned under suitable conditions.

[0052] Step S106: In the case where the first condition and the second condition are satisfied at the same time, a preset defrosting program is called to perform defrosting treatment on the outdoor unit of the air conditioner.

[0053] In the present embodiment, the preset defrosting program can be a reverse defrosting program for the heat pump, for example, reversing the flow direction of refrigerant by reversing valve, converting the outdoor heat exchanger (evaporator) to condenser, delivering heat to it, and increasing its temperature to melt the frost. Specifically, the controller triggers the reversing valve to switch and reverse the flow direction of refrigerant. The outdoor heat exchanger starts to absorb heat from the refrigerant and its temperature rises. The frost or ice gradually melts into water, which can be understood as water carrying dirt at this time.

[0054] The preset defrosting program can also be to control the electric heating wire to perform heating, which is preset around the outdoor heat exchanger. When the defrosting program is triggered, the controller energizes the heating to raise the temperature of the heat exchanger surface and melt the frost.

[0055] In some embodiments, the preset defrosting program can also be intermittent shutdown defrosting, especially in the case of high outdoor temperature, when the air conditioner is shut down, the frost will melt on its own within a period of time due to the outdoor environment temperature being higher than the temperature of the frost.

[0056] Step S108: After the defrosting program ends, the fan of the outdoor unit of the air conditioner is controlled to perform reverse rotation to at least blow off the water carrying dirt on the outdoor heat exchanger.

[0057] In the present embodiment, the reverse rotation can be performed at the maximum speed to at least blow off the water carrying dirt on the outdoor heat exchanger. In the case of more dirt, the maximum speed reverse rotation can produce strong airflow to completely remove the water and stubborn dirt on the surface of the heat exchanger.

[0058] In the present embodiment, the reverse rotation can also be performed at the medium speed to at least blow off the water carrying dirt on the outdoor heat exchanger. In the case of less dirt, the medium speed reverse rotation can effectively remove most of the water and slight dirt on the surface of the heat exchanger, while reducing the wear and tear on the fan and the system.

[0059] In some cases, the reverse rotation can be performed at variable speed, which can use higher speed at the beginning of cleaning, gradually reduce to medium or lower speed, to adapt to the cleaning needs of different dirt and frost thickness.

[0060] In this embodiment, the dirt can be dust and small particles. It can be understood that, in the normal operation process, dust and small particles in the air can adhere to the surface of the heat exchanger. The dirt can also be fallen leaves and weeds. If the outdoor unit of the air conditioner is installed in an area close to trees or grass, fallen leaves and small plant fragments can be brought to the surface of the heat exchanger by the wind. Small plant debris such as weeds and branches can also enter the heat exchanger area with the wind. The dirt can also be insects and small animal carcasses. Small insects sometimes enter the interior of the outdoor unit and adhere to the heat exchanger, especially in summer. The dirt can also be light garbage such as plastic bags and paper scraps. When the wind blows or the garbage falls, light plastic bags, paper scraps and the like can be brought to the surface of the outdoor unit heat exchanger by the wind.

[0061] In this embodiment, after the defrosting program ends, the fan of the outdoor unit of the air conditioner is controlled to perform reverse rotation. In addition to being able to blow off the dirt-carrying melt water on the surface of the outdoor unit heat exchanger, it can also blow off the dirt-carrying melt water on the surface of the fan blades, the outdoor unit shell and the shell grating, the connecting pipeline and the pipeline interface, and the outer surface of the electrical components. Specifically, when the fan is reversed, the melt water adhering to the fan blades can be blown off. The surface of the outdoor unit shell can form a water film due to the condensation water or the melting of the frost, and the airflow when the fan is reversed can blow off these water droplets or water film from the surface of the shell. The grating part also serves as an air inlet and outlet passage, and melt water can also accumulate in this area. The reverse rotation of the fan can effectively blow away the water in these areas and prevent water from remaining and causing corrosion. The refrigerant pipeline (especially the part exposed to the outside) can form condensation water during operation, and the airflow of the fan reversed can help blow off the melt water outside the pipeline. The connection interface can accumulate melt water due to the connection seal and the like, and the reverse rotation of the fan can remove the water in these interfaces. The outer surface of the electrical control box or other external electrical components can adhere to the melt water after defrosting, and the airflow of the reversed fan can blow away the water.

[0062] In this embodiment, the melt water can be melt water of frost or melt water of ice.

[0063] In the air conditioner self-cleaning method provided in this embodiment, by dynamically judging the frosting state of the heat exchanger in the heating mode, the triggering time of the defrosting program can be accurately controlled, thereby improving the effectiveness of the defrosting. Especially when the first condition and the second condition of the heat exchanger both meet the set condition, the preset defrosting program is called in time, and after the defrosting ends, the dirt is blown off by the reverse rotation of the fan, which greatly reduces the accumulation of dust and dirt on the surface of the heat exchanger. In this way, the air conditioner can continuously maintain a high heat exchange efficiency, while reducing the need for manual cleaning, improving the operation reliability and energy saving effect of the air conditioner.

[0064] In some embodiments, the first condition is a condition for determining whether a temperature difference of a decrease of the saturation temperature of the refrigerant within a certain time window satisfies a temperature threshold; and the second condition is a condition for determining whether the saturation temperature of the current refrigerant can cause the outdoor unit heat exchanger to frost.

[0065] In the present embodiment, the certain time window can be a time window in the early stage within the preset time. It can also be a time window in the middle stage within the preset time, and it can also be a time window in the early stage within the preset time. The time window can be a larger time window, for example, it can account for one-fifth of the preset time. It can also be a smaller time window, for example, it can account for one-tenth of the preset time.

[0066] In the present embodiment, the temperature threshold is a preset temperature difference value, which can be 2°C, 3°C, 5°C, etc. The temperature threshold is determined by experiment.

[0067] In a specific embodiment, the first condition can be: in the case of a preset time of 1 hour, the saturation temperature of the refrigerant at the 50th minute - the saturation temperature of the refrigerant at the 60th minute ≥ 2°C.

[0068] It can be understood that first, the saturation temperature corresponding to the system low pressure is calculated based on the pressure state of the entire refrigeration system, which reflects the overall state of the refrigerant in the system under the current pressure. Compared with the actual temperature, the system low pressure can provide a comprehensive evaluation of the running state of the entire system, and is more suitable for judging whether a system-level phenomenon such as frosting occurs. Second, measuring the system pressure and converting it to the saturation temperature is often simpler and more reliable than directly measuring the actual temperature of the refrigerant. The system low pressure can be measured by a pressure difference sensor, and the temperature is indirectly judged by measuring the pressure, which not only simplifies the system design, but also reduces potential measurement errors. The measurement of the actual temperature value can be affected by many factors, such as the arrangement position of the sensor, the refrigerant flow rate, the sensor accuracy, etc. These factors can cause the measured actual temperature value to not completely reflect the state of the refrigerant on the entire heat exchanger surface. In contrast, the measurement of the system pressure is more stable and reliable, and the saturation temperature value calculated from it can more accurately represent the frosting conditions of the entire system. Finally, in actual working conditions, the actual temperature of the refrigerant can vary at different parts of the heat exchanger, while the system low pressure and the corresponding saturation temperature provide an average reflection of the working conditions of the entire system. This is particularly important for determining whether the frosting condition is met, because the frosting process involves temperature changes on the entire heat exchanger surface, not just the actual temperature at a certain point.

[0069] Therefore, in summary, in the present embodiment, the first condition evaluates the cooling effect of the air conditioner in a certain time window by determining whether the temperature difference of the saturation temperature of the refrigerant decreases to meet the temperature threshold, thereby ensuring the effective reduction of the surface temperature of the heat exchanger. The second condition directly determines whether the refrigerant has the potential to make the outdoor unit heat exchanger frost based on the current saturation temperature of the refrigerant. The saturation temperature, as the phase change temperature of the refrigerant under a certain pressure, can accurately reflect the overall thermodynamic state of the system and the frosting capacity of the refrigerant, and is not affected by local temperature fluctuations or sensor location, thereby improving the accuracy of the judgment and the operating efficiency of the system. This way can ensure that the defrosting program is started in time under suitable conditions, optimize the self-cleaning effect of the air conditioner and prolong the service life of the equipment.

[0070] In some embodiments, the step of calling the preset defrosting program to defrost the outdoor unit of the air conditioner includes:

[0071] In the defrosting program, when it is detected that the defrosting temperature is greater than zero degrees Celsius, the fan of the outdoor unit of the air conditioner is controlled to perform reverse rotation to blow off the loose frost or ice layer carrying dirt.

[0072] In this embodiment, in this step, the control of the fan of the outdoor unit of the air conditioner to perform reverse rotation can be to perform reverse rotation at a medium speed, or to perform reverse rotation at a maximum speed. It can also be to perform reverse rotation at a dynamically variable speed.

[0073] Understandably, firstly, when the temperature of frost and ice rises above 0°C, although they haven't completely melted, they have partially detached from the heat exchanger surface. At this point, the frost and ice on the surface are loose but may still continue to melt, forming a water film. As the defrosting temperature rises, the meltwater that hasn't been blown away in time will gradually evaporate, especially as the temperature rises further, this moisture will evaporate quickly. This process not only consumes the air conditioner's heat energy but may also make the dust and condensate on the heat exchanger surface more tightly bound, making it difficult to remove. By immediately reversing the fan when the defrosting temperature is >0°C, the frost layer and the dirt it contains can be blown away before a large amount of meltwater has formed, reducing the generation and evaporation of condensate, thus keeping the heat exchanger surface clean and ensuring efficient system operation. Secondly, when the defrosting temperature exceeds 0°C, the structure of the frost layer has become fragile and easily detached. The powerful airflow from the fan, which can be reversed at maximum speed, can quickly remove these fragile frost layers and ice chips, exposing the heat exchanger surface. Finally, when the temperature of the frost and ice layers rises above 0°C, although they haven't completely melted, they have partially detached from the heat exchanger surface. At this point, the loosened frost and ice may continue to melt, forming a water film. This water film easily combines with dust and dirt on the heat exchanger surface. If not removed promptly, this water film containing dirt may re-adhere to the heat exchanger surface in subsequent processes, significantly reducing the cleaning effect. By reversing the fan at this point to blow away the loosened frost and ice, the re-adhesion and accumulation of dirt can be effectively prevented, thereby improving the self-cleaning effect.

[0074] Therefore, in summary, during the defrosting process, when the defrosting temperature is detected to be >0℃, the outdoor unit's fan should be immediately reversed to blow away loose frost or ice layers carrying dirt. The advantage of this implementation is that when the frost or ice layer has largely detached from the heat exchanger surface at temperatures above 0℃ but has not yet completely melted, the fan reversal can promptly remove these loose residues, preventing them from continuing to melt and forming a water film containing dirt, thus avoiding the recombination of dust and condensate. This operation removes dirt before defrosting is complete, helping to optimize the cleaning effect on the heat exchanger surface, reducing impurities that may remain during the melting of frost or ice, improving overall cleaning efficiency, and extending the service life of the air conditioner.

[0075] like Figure 2 As shown, in some embodiments, if the first condition and / or the second condition are not met, the method further includes:

[0076] Step S110: Directly control the fan of the outdoor unit of the air conditioner to reverse so as to blow away at least the condensate carrying dirt on the heat exchanger of the outdoor unit.

[0077] In this embodiment, during this step, controlling the outdoor unit fan of the air conditioner to reverse can be done at a medium speed, at the maximum speed, or at a dynamically variable speed.

[0078] Understandably, if an air conditioner has been running in heating mode for a period of time without triggering the defrost procedure or meeting the conditions required for frosting (i.e., not meeting the first and / or second conditions), it indicates that the air conditioner may never be able to frost under the current environment and operating conditions. At this point, continuing to attempt frosting and defrosting is pointless, as the air conditioner has never entered a frosted state. By directly controlling the fan to reverse and promptly blowing away any remaining condensate, unnecessary energy consumption and equipment load can be avoided, ensuring that the air conditioner maintains its basic self-cleaning function even in complex or adverse environments. This method takes immediate action upon detecting that the frosting conditions cannot be met, rather than waiting for the entire defrost procedure to run. This flexibility allows the air conditioner to quickly adapt to different environmental conditions, avoiding lengthy defrosting processes and improving the efficiency of self-cleaning operations. When frosting conditions are insufficient, quickly blowing away condensate also ensures that the system promptly returns to normal operation, avoiding prolonged ineffective waiting and energy waste.

[0079] like Figure 3 As shown, in some embodiments, after the step of operating the air conditioner in heating mode and before the step of determining whether the outdoor unit simultaneously meets the first condition and the second condition, the method further includes:

[0080] Step S1032: Determine whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature; wherein, the target saturation temperature is used to measure whether the outdoor unit heat exchanger is tending to frost; wherein, when the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, it indicates that the outdoor unit heat exchanger is tending to frost or has already frostted.

[0081] In this embodiment, the target saturation temperature is a parameter used to measure whether the outdoor unit heat exchanger is prone to frosting. The target saturation temperature can be a predetermined fixed value or a dynamic value. Specifically, in some cases, the target saturation temperature can be set to a fixed value based on long-term experience or standards under specific operating conditions. This method is simple, reliable, and suitable for scenarios with relatively stable or minimally changing environmental conditions.

[0082] In some embodiments, the target saturation temperature can be set as a dynamic value, for example, the target saturation temperature can be dynamically adjusted according to the change of the ambient temperature. For example, at a higher ambient temperature, the target saturation temperature can be appropriately increased, because at this time the refrigerant needs a lower temperature to reach the frosting condition. Conversely, at a lower ambient temperature, the target saturation temperature can be set to a lower value, to adapt to the situation that the refrigerant is more likely to reach the frosting point. This dynamic adjustment helps to more accurately control the system under different temperature conditions, so that the frosting and defrosting process is more efficient. The target saturation temperature can also be dynamically adjusted with the change of the ambient humidity. When the humidity is high, the moisture content in the air is large, and the refrigerant is more likely to frost on the surface of the heat exchanger, so the target saturation temperature can be set higher to ensure suitable frosting conditions. While in a low humidity environment, the target saturation temperature can be set lower to enhance the frosting ability of the refrigerant, to make up for the difficulty of frosting caused by insufficient humidity. This dynamic adjustment method can better adapt to changes in humidity and improve the defrosting efficiency of the system.

[0083] In some embodiments, the target saturation temperature can also be dynamically adjusted based on the comprehensive change of the ambient temperature and humidity. The air conditioner can monitor the current ambient temperature and humidity in real time through sensors, comprehensively analyze the influence of these two factors on the frosting conditions, and dynamically adjust the target saturation temperature. For example, in a high temperature and high humidity environment, the target saturation temperature may need more accurate regulation to ensure that the system can effectively frost and not trigger the defrosting program too early.

[0084] In some embodiments, the target saturation temperature is also self-adaptively learned and adjusted through historical data and running experience. For example, according to the running effect of the air conditioner under different environmental conditions, the setting of the target saturation temperature is continuously optimized to form a dynamic and self-adaptive target temperature regulation mechanism, further improving the intelligent level and running efficiency of the air conditioner.

[0085] In a specific embodiment, the target saturation temperature can be set by the following method.

[0086] First, detect the current outdoor ambient temperature T1, and set the target saturation temperature by the following rules:

[0087] When T1<-15℃, the target saturation temperature = outdoor ambient temperature T1-5℃;

[0088] When -15℃≤T1≤5℃, the target saturation temperature = outdoor ambient temperature T1-10℃;

[0089] When 5℃

[0090] When T1 > 24℃, the target saturation temperature = T1 - 10℃.

[0091] Step S1034: If the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, determine whether the air conditioner is in the defrosting state.

[0092] In this embodiment, the power consumption of the air conditioner compressor can be increased by 10% based on the original power consumption. For different models and powers of compressors, the increase in power consumption can vary between 5% and 20%. A smaller increase (e.g. 5%) is suitable for compressors with higher power to avoid excessive load, while a larger increase (e.g. 15%-20%) is suitable for compressors with lower power to ensure sufficient cooling capacity. The air conditioner can dynamically adjust the power consumption increase according to real-time refrigerant temperature, environmental conditions, compressor load, and other factors. For example, in high ambient temperature conditions, the compressor may require a larger power consumption increase (e.g. 15%) to sufficiently reduce the refrigerant temperature; while in low ambient temperature conditions, a smaller power consumption increase (e.g. 5%) can be selected to save energy.

[0093] In this embodiment, the several minutes can be three minutes, four minutes, five minutes, or the like. In some cases, a short period of increased power operation of 1-2 minutes can be sufficient to significantly reduce the refrigerant temperature and quickly reach the target saturation temperature. In more severe environmental conditions, such as high temperature and high humidity environments, the compressor may need to run for 4-5 minutes to reduce the refrigerant temperature below the target temperature. In this case, longer periods of increased power operation can ensure sufficient cooling effect, which is suitable for cases where the heat exchanger cooling is more difficult.

[0094] In some embodiments, the several minutes can also be dynamically adjusted according to the response speed of the air conditioner and actual needs.

[0095] The embodiment measures whether the current outdoor unit heat exchanger tends to frost by judging whether the refrigerant saturation temperature is less than or equal to the target saturation temperature after the air conditioner is operated in the heating mode, and takes corresponding measures to optimize the defrosting process. The advantage of this embodiment is that by accurately monitoring the relationship between the refrigerant saturation temperature and the target saturation temperature, it ensures that the heat exchanger surface is as frosty as possible under different working conditions to facilitate the removal of dirt on the heat exchanger by the melting water after frosting and defrosting, thereby achieving more effective self-cleaning operation. If the refrigerant saturation temperature does not reach the frosting condition, the compressor power consumption is increased to further reduce the temperature, thereby increasing the possibility of frosting and ultimately improving the defrosting efficiency. This method not only improves the accuracy of frosting and defrosting, but also enhances the self-adaptive ability of the system in complex environments, ensuring that the air conditioner can maintain efficient cleaning and stable operation under various operating conditions.

[0096] In some embodiments, after the step of judging whether the air conditioner is in a defrosting state, the method further comprises:

[0097] When the air conditioner is not in a defrosting state, judging whether the air conditioner has accumulated running for a preset time in the heating mode.

[0098] It can be understood that by checking whether the air conditioner has accumulated running for a preset time, it is ensured that the system is running sufficiently so that the temperature of the heat exchanger surface is low enough to promote frosting. In this way, the situation that the heat exchanger fails to reach the frosting condition due to insufficient running time is avoided, ensuring that the air conditioner attempts to trigger the defrosting program only under suitable conditions, thereby improving the accuracy and effectiveness of defrosting.

[0099] In the present embodiment, the preset time can be one hour, but also two hours or three hours, etc. The preset time of one hour is suitable for the case where the environmental conditions are relatively mild and the heat exchanger cooling speed is relatively fast. In this case, the heat exchanger usually reaches the frosting condition within a short period of time, so one hour of running time is sufficient to ensure that the air conditioner has the necessary cooling and frosting capacity. The preset time of two hours is suitable for the case where the environmental conditions are slightly challenging, such as high environmental temperature or low humidity. In this case, the system may need longer running time to sufficiently cool the heat exchanger to reach the frosting threshold. The two-hour time period provides more time to achieve this goal. The preset time of three hours or more is suitable for extreme environmental conditions, such as very high environmental temperature, low humidity or heavy system load. In this case, the heat exchanger cooling speed may be slow, and more time is needed to ensure sufficient cooling to promote frosting. Long running time ensures that the air conditioner has enough time for heat exchange to reach effective frosting conditions. It can be understood that the present embodiment does not limit whether it is several hours or half an hour.

[0100] If the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, it is further determined whether the air conditioner enters a defrosting state.

[0101] In the present embodiment, real-time determination means that the controller continuously monitors and compares the saturation temperature of the refrigerant with the target saturation temperature. When the air conditioner is in the heating mode, the controller collects the saturation temperature data of the refrigerant in real time through the sensor and compares it with the preset target saturation temperature immediately. Once it is detected that the saturation temperature of the refrigerant is lower than or equal to the target saturation temperature, the controller will immediately perform the subsequent operation, such as determining whether it is necessary to enter the defrosting state.

[0102] In the present embodiment, periodic determination means that the controller collects the saturation temperature of the refrigerant periodically in a preset time interval and compares it with the target saturation temperature. For example, the controller can perform temperature determination once every 5 minutes, 10 minutes or longer time interval. In this way, it is not necessary to continuously monitor, but to collect and determine the temperature data through the time triggered way.

[0103] The present embodiment ensures that the air conditioner triggers the defrosting program only when it has sufficient cooling and frost forming conditions by further determining whether the air conditioner has accumulated operation to the preset time when it is not in the defrosting state, and monitoring in real time or periodically whether the saturation temperature of the refrigerant is lower than the target saturation temperature when the preset time is not reached. This mechanism effectively avoids the invalid defrosting operation caused by insufficient operation, improves the accuracy and effect of defrosting, optimizes the system energy consumption, prolongs the service life of the equipment, and enhances the intelligent and adaptive ability of the air conditioner under different environmental conditions.

[0104] In some embodiments, before the step of determining whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, the method further comprises:

[0105] controlling the fan of the outdoor unit of the air conditioner to perform reverse rotation at the maximum speed for preliminary cleaning.

[0106] In this embodiment, by controlling the fan of the air conditioner outdoor unit to perform reverse rotation at maximum speed to perform preliminary cleaning before determining whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, the dust, debris and loose dirt adhering to the surface of the heat exchanger can be effectively removed. This preliminary cleaning is performed before the defrosting and defrosting process, which not only helps to improve the uniformity and effect of frosting, but also reduces the re-attachment of dirt during the defrosting process, avoiding the combination of dirt and frost layer affecting the defrosting efficiency. By removing surface contaminants at an early stage, subsequent frosting and defrosting operations are more efficient, thereby prolonging the service life of the equipment and improving the overall operating efficiency and reliability of the system.

[0107] In some embodiments, after the step of controlling the fan of the air conditioner outdoor unit to perform reverse rotation at maximum speed to perform preliminary cleaning, and before the step of determining whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, the method further comprises:

[0108] Detecting the current outdoor temperature.

[0109] Determining the target saturation temperature based on the current outdoor temperature and a preset target saturation temperature setting rule.

[0110] In this embodiment, the target saturation temperature setting rule can be a rule for determining the required saturation temperature of the refrigerant of the air conditioner under different environmental conditions.

[0111] In this embodiment, the target saturation temperature setting rule can be a target saturation temperature setting rule based on outdoor temperature, a target saturation temperature setting rule based on environmental humidity, or a target saturation temperature setting rule considering comprehensive environmental factors. In some embodiments, in this embodiment, after preliminary cleaning by controlling the fan of the air conditioner outdoor unit to perform reverse rotation at maximum speed, the current outdoor temperature is further detected, and the target saturation temperature is determined based on this temperature and the preset target saturation temperature setting rule, which can achieve more accurate temperature control. This process ensures that the target saturation temperature fully considers real-time external environmental factors, so that the system can dynamically adjust the conditions of frosting and defrosting, thereby optimizing the operating state of the refrigerant and improving the accuracy of frosting and the effectiveness of defrosting. By combining real-time environmental data and setting rules, the system can adaptively adjust under different environmental conditions, ensuring that the air conditioner can operate efficiently under various climate conditions, while reducing energy consumption and prolonging the service life of the equipment.

[0112] In a specific embodiment, the target saturation temperature can be set in the following way.

[0113] First, detect the current outdoor temperature T1, and set the target saturation temperature by the following rule:

[0114] When T1<-15℃, target saturation temperature = outdoor environment temperature T1-5℃;

[0115] When -15℃≤T1≤5℃, target saturation temperature = outdoor environment temperature T1-10℃;

[0116] When 5℃

[0117] When T1>24℃, target saturation temperature = outdoor environment temperature T1-10℃.

[0118] In some embodiments, before the step of operating the air conditioner in the heating mode to at least reduce the surface temperature of the outdoor unit heat exchanger, the method further comprises:

[0119] identifying whether the outdoor unit of the air conditioner has dirty blockage based on a preset air conditioner outdoor unit dirty blockage identification rule set; wherein the air conditioner outdoor unit dirty blockage identification rule set at least includes the following dirty blockage identification rule: in the case that the pressure difference before and after the air conditioner outdoor unit heat exchanger reaches a pressure difference threshold value and the rotation speed of the outdoor unit fan is lower than a rotation speed threshold value, the outdoor unit of the air conditioner is identified as dirty blockage.

[0120] In the present embodiment, the air conditioner outdoor unit dirty blockage identification rule set can be represented as a set composed of a plurality of rules for identifying the dirty blockage condition of the outdoor unit of the air conditioner. These rules judge whether there is a dirty blockage phenomenon by analyzing and judging various operating parameters of the outdoor unit, such as the pressure difference before and after the heat exchanger, the fan rotation speed, the air flow, the temperature change, etc. For example, the air conditioner outdoor unit dirty blockage identification rule set can include: a pressure difference identification rule, a fan rotation speed identification rule, an air flow identification rule, and a temperature change identification rule, etc.

[0121] In the present embodiment, the pressure difference threshold value can be represented as a critical standard that the pressure difference before and after the heat exchanger of the outdoor unit of the air conditioner reaches or exceeds a certain value. The pressure difference threshold value can be used to judge whether the heat exchanger has a situation of air flow obstruction. In the case of identifying that the outdoor unit of the air conditioner has dirty blockage, an instruction of air conditioner self-cleaning is generated, or a request of air conditioner self-cleaning is generated; wherein the request is sent to the user and is used to indicate the request of generating the instruction of air conditioner self-cleaning.

[0122] In the embodiment, when it is identified that the outdoor unit of the air conditioner is dirty and blocked, the controller can generate a request for air conditioner self-cleaning and send the request to the user, for example, to the user's smart phone or the air conditioner remote controller. The request can inform the user of the current operation state of the device and suggest the user to take corresponding actions. Specifically, the request not only informs the user that the air conditioner may be dirty and blocked, but also explicitly prompts the user to generate a self-cleaning instruction to restore the normal operation efficiency of the device. In the embodiment, by identifying whether the outdoor unit of the air conditioner is dirty and blocked based on the preset air conditioner outdoor unit dirty and blocked identification rule set and generating an instruction or request for air conditioner self-cleaning when the dirty and blocked condition is identified, the device can be actively maintained at an early stage of the problem. This method uses key parameters such as the pressure difference before and after the heat exchanger and the fan speed to effectively identify the dirty and blocked state of the heat exchanger, thereby avoiding system performance degradation, increased energy consumption, or device damage caused by dirty and blocking. By automatically triggering a self-cleaning instruction or reminding the user to perform cleaning operations when dirty and blocking occurs, the air conditioner can restore normal operation efficiency in a timely manner, prolong the service life of the device, and reduce the risk of failure. This preventive maintenance strategy improves the reliability and intelligence level of the air conditioner, providing a more convenient user experience.

[0123] In one possible specific implementation, the preset air conditioner outdoor unit dirty and blocked identification rule set can include the following specific identification rules:

[0124] Rule 1: Install a pressure difference switch before and after the heat exchanger (i.e., when the pressure difference between the two points is greater than a certain set value, the pressure difference switch is triggered), and set the pressure difference switch trigger value to X Pa (recommended 50, which can be determined according to actual conditions for different heat exchangers and use conditions). When the unit is operating normally, the fan speed is continuously detected to be ≤ Y r / min (recommended fan rated speed, which can be determined according to actual conditions for different units) for a short period of time, and the pressure difference switch is in the triggered state. Then mark that the heat exchanger is dirty and blocked.

[0125] Rule 2: Each time the machine is turned on, the outdoor fan is first operated at a set speed (recommended rated speed and rated speed * 50% of the two set speeds to avoid false positives) for about 1 minute, and the fan operating current, fan speed, and outdoor temperature are detected and recorded. Take the minimum fan operating current recorded during normal operation as the reference (or set a corresponding reference value). If the corresponding fan current is detected to be > fan current reference value * 110% (recommended value, which can be determined according to actual conditions), mark that the heat exchanger is dirty and blocked.

[0126] Rule 3: Equipped with pressure sensors installed before and after the heat exchanger, detect the atmospheric pressure before and after the heat exchanger, calculate the pressure difference before and after, and refer to method 1 for the rest of the method. When the corresponding pressure difference is greater than 1.5 times the pressure difference reference value (recommended value, which can be determined according to actual conditions), it is marked as the heat exchanger has been dirty and blocked. Or use a pressure difference switch instead of the pressure sensors before and after the heat exchanger, set the appropriate trigger value (recommended 50, different heat exchangers and use conditions can be determined according to actual conditions), refer to method 1 for detection, and if the pressure difference switch is triggered, it is marked as the heat exchanger has been dirty and blocked.

[0127] In one possible embodiment, in the case of detecting that the heat exchanger is dirty and blocked, the user can be prompted to inquire about the time of the scheduled automatic cleaning, and the user can input the specific scheduled time through the intelligent terminal.

[0128] First, when the scheduled time is reached, the controller starts the heating mode of the air conditioner, and in the heating mode, the fan of the outdoor unit of the air conditioner is controlled to reverse for a few minutes, for example, it can be reversed for 2 minutes, and further, it can be reversed at the maximum speed for 2 minutes to blow off some easily blown off garbage and debris attached to the outdoor unit of the air conditioner. For example, some large particles of dust, plastic bags, etc. Therefore, the maximum speed for 2 minutes can achieve preliminary cleaning. It can be understood that after switching to the heating mode, the heat exchanger of the air conditioner outdoor unit is actually the evaporator, and the high-temperature low-pressure liquid refrigerant evaporates continuously in the heat exchanger. At this time, the temperature of the copper pipe of the heat exchanger is continuously reduced, and when it is lower than the dew point temperature, water will be condensed, and when the temperature is reduced to below zero degrees, the surface will be frozen.

[0129] Then, based on the current outdoor environment temperature T1, the speed of the outdoor unit fan is reduced to a target value. Specifically, the current outdoor environment temperature T1 can be detected, and it can be understood that the specific value of the current outdoor environment temperature T1 can be detected by the temperature sensor configured on the outdoor unit of the air conditioner. For different outdoor environment temperatures T1, the speed of the outdoor unit fan can be reduced to different degrees, which can be:

[0130] When T1 < -15℃, the outdoor unit fan is reduced to 2 / 3 of the normal control speed, and the other normal control;

[0131] When -15℃ ≤ T1 ≤ 5℃, the outdoor unit fan is reduced to 1 / 2 of the normal control speed, and the other normal control;

[0132] When 5℃ < T1 ≤ 24℃, the outdoor unit fan is reduced to 1 / 3 of the normal control speed, and the other normal control;

[0133] When T1 > 24℃, the outdoor unit fan is reduced to the minimum control speed, and the other normal control.

[0134] It can be understood that different ambient temperatures have different effects on frosting, and are also related to air humidity. For a scene that is more prone to frosting, the fan speed can be increased to increase air circulation, so that more water vapor in the air adheres to the outer surface of the heat exchanger. The lower the room temperature, the lower the water vapor content in the air. Therefore, increasing air circulation can promote frosting. Correspondingly, the higher the room temperature, the higher the water vapor content in the air. Therefore, the fan does not need to run very fast, because the water vapor is sufficient. As long as the temperature of the outer surface of the heat exchanger is lower than the dew point temperature, water can be condensed. If it is lower, it can be below 0°C to frost and freeze.

[0135] Then, the current system low pressure is detected, and the detected saturation temperature is compared with a preset target saturation temperature in size, wherein the setting rule of the target saturation temperature is related to the current outdoor ambient temperature T1, and specifically:

[0136] When T1<-15℃, the target saturation temperature is ambient temperature-5℃;

[0137] When-15℃≤T1≤5℃, the target saturation temperature=ambient temperature-10℃;

[0138] When 5℃

[0139] When T1>24℃, the target saturation temperature=ambient temperature-10℃.

[0140] In the case of saturation temperature>target saturation temperature, the load of the compressor is increased and runs continuously for several minutes. For example, the current load of the compressor can be increased by 10% and run continuously for 3 minutes. After running for several minutes, the size between the current detected system low pressure and the preset target low pressure is judged again. It can be understood that the purpose of judging the size between the current saturation temperature and the preset target saturation temperature is to make the outdoor unit of the air conditioner, especially the outer wall of the heat exchanger, frost as much as possible under different working conditions. Frosting can strip off dirt and other dirt on the outer wall of the heat exchanger or other outer walls by condensing water, so as to be blown away after defrosting. Therefore, it is necessary to judge whether the saturation temperature is less than or equal to the target saturation temperature. In the case of saturation temperature≤target saturation temperature, it can be further judged whether the air conditioner outdoor unit has entered the defrosting state. Correspondingly, if the saturation temperature>target saturation temperature, it means that the air conditioner outdoor unit has a low possibility of frosting. Correspondingly, if the saturation temperature>target saturation temperature, the air conditioner can continue to run in heating mode, and the load can be increased by 10% based on the original load, so that the temperature of the heat exchanger of the air conditioner outdoor unit can be further reduced, and the saturation temperature≤target saturation temperature.

[0141] When the saturation temperature is less than or equal to the target saturation temperature, further detection is needed to determine if the outdoor unit of the air conditioner has entered defrosting mode. It's understandable that many air conditioners are now equipped with a control program that automatically enters defrosting mode when the outdoor unit is frosted, in order to remove the frost layer. Conversely, if the outdoor unit is not detected to be in defrosting mode—for example, if the outdoor unit is indeed not frosted, the preset defrosting program is not automatically triggered; or if the outdoor unit is frosted, but the frost layer is not thick enough, the preset defrosting program is not automatically triggered either. In this case, it is necessary to further determine whether the air conditioner has accumulated one hour of operation. This one hour is simply a preset value; it could be 1.5 hours, 2 hours, etc. This further determination of whether the air conditioner has accumulated one hour of operation means determining whether the air conditioner has been running in heating mode for one hour. In other words, it is necessary to determine whether the outdoor unit of the air conditioner has been operating sufficiently to achieve adequate cooling. Therefore, this one hour is merely a preset value for determining whether the air conditioner has been operating sufficiently. If the air conditioner has not been running continuously for 1 hour, the surface of the air conditioner is not running sufficiently, and the outer surface of the outdoor unit, especially the heat exchanger, has not been cooled sufficiently. Therefore, the air conditioner needs to run sufficiently. This sufficient running can be for 1 hour, or it can be determined after running for 1 hour, or every few minutes. It is understandable that the current system low pressure and the preset target low pressure can be determined only after the condition of running for 1 hour is met, or the current system low pressure and the preset target low pressure can be determined every few minutes. For example, the air conditioner may directly enter the defrosting state at the 25th minute, so there is no need to further determine whether it has run for 1 hour. Correspondingly, if it has been running continuously for 1 hour, then it is necessary to further determine whether conditions (1) and (2) are met simultaneously. Condition (1): The system low pressure at the 50th minute - the system low pressure at the 60th minute ≥ 2℃; Condition (2): The system low pressure at the 60th minute < 0℃. If both conditions are met, it means that the heat exchanger casing is already frosted, but the preset defrosting program has not been triggered. In this case, the existing defrosting level needs to be called to defrost the outdoor unit of the air conditioner. Correspondingly, if either condition (1) or condition (2) is not met, it means that the heat exchanger is not frosted but has condensation. If it continues to run, it may not be able to frost. Therefore, in this case, the air conditioner can be stopped directly, and only the outdoor unit fan can be reversed to blow away the liquid water on the outdoor unit, thus achieving self-cleaning of the outdoor unit. It is understandable that if the heat exchanger surface is frosted, the system low pressure will decrease, so condition (1) is added.

[0142] Finally, in the case that the air conditioner outdoor unit has entered the defrosting state is detected, and the defrosting temperature > 0 ℃ is further detected, the fan of the air conditioner outdoor unit is controlled to reverse at the maximum speed for 1 minute, then the fan is paused, and the end of the defrosting program of the air conditioner is waited. After the end of the defrosting program, the air conditioner can be controlled to stop running, and only the fan of the outdoor unit is controlled to reverse at the highest speed, for example, it can be reversed for 10 min to blow off the liquid water on the outdoor unit. It can be understood that the defrosting temperature > 0 is detected, and the fan is directly reversed. Because at this time the frost and ice layer has not been completely defrosted. But the surface combined with the heat exchanger has basically melted, and actually has been separated from the heat exchanger. The surface of the heat exchanger will form a water film, which will combine with the dust on the surface of the heat exchanger, continue to defrost, and then evaporate the condensed water. Affect the combination effect of the condensed water and the dust. At this time, the reverse is clean, and the cleaning effect is relatively obvious. Therefore, in this case, the fan can be directly controlled to reverse and blow off without waiting for the end of the defrosting program. It can be understood that at this time the blowing off may be garbage and ice debris. After the end of the defrosting program, a large part of the garbage and ice debris has been blown off, and the frost and ice layer that has not been blown off has also been defrosted into liquid water because of the defrosting program. At this time, the fan of the outdoor unit can be controlled to reverse at the highest speed for 10 min to achieve the maximum degree of self-cleaning.

[0143] It can be understood that, whether it is liquid water formed after frosting due to defrosting program, or condensate water formed by condensation throughout the process without frosting, all of them carry dust and dirt, and through this cleaning method, the difficult-to-remove dirt on the outdoor unit can be removed to a great extent. It can also be understood that, although some larger garbage and debris can be removed through the above preliminary cleaning, some garbage and debris that can be easily blown away, such as plastic bags, can be removed. However, some stubborn dust adhering to the outdoor unit of the air conditioner, especially the outer wall of the heat exchanger, is difficult to be blown away through the preliminary cleaning method, because in this method, the heating mode is first run to reduce the temperature of the outdoor unit of the air conditioner, especially the surface temperature of the heat exchanger. When the surface temperature of the heat exchanger is reduced to the dew point temperature, the water vapor in the air will form condensate water on the outdoor unit of the air conditioner, especially on the surface of the heat exchanger, and the condensate water will wet the stubborn dirt on the surface of the heat exchanger. For example, some stubborn dust. By continuously running the heating mode, the surface temperature of the outdoor unit of the air conditioner, especially the heat exchanger, is further reduced, and when it is reduced to below zero, the condensate water will freeze. The role of frosting is to separate the stubborn dirt wetted from the surface of the heat exchanger. After frosting is completed, a preset defrosting program is triggered to defrost, and the frost layer mixed with stubborn dirt is defrosted into condensate water mixed with stubborn dirt. Before the defrosting program ends, but when the defrosting temperature is detected to be greater than 0℃, the fan is first reversed for a short time (for example, 1 minute) to blow away a part of the ice layer and the frost layer mixed with dirt that has been separated. After the defrosting program ends, the fan can be reversed at the maximum speed for a long time (for example, 10 minutes) to completely blow away the dirt.

[0144] According to an embodiment of the present application, an electronic device is provided, referring to Figure 4 The electronic device in the embodiment can include one or more of the following components: a processor, a network interface, a memory, a non-volatile memory, and one or more application programs, wherein the one or more application programs can be stored in the non-volatile memory and configured to be executed by the one or more processors, and the one or more programs are configured to perform the method as described in the foregoing method embodiments.

[0145] According to an embodiment of the present application, an air conditioner is provided, including the air conditioner self-cleaning method and the electronic device described above.

[0146] According to an embodiment of the present application, a computer readable storage medium is provided, which stores a computer program, and the computer program is executed by a computer to make the computer execute the method described in any of the above embodiments.

[0147] According to the embodiments of the present application, a computer program product including instructions, which, when executed by a computer, causes the computer to perform the method described in any of the embodiments.

[0148] It should be noted that the terms "first", "second" and the like in the description and in the claims of the present application are intended to distinguish between similar objects and not necessarily in an ordinal sense. It will be understood that the terms so used are interchangeable under appropriate circumstances and embodiments of the application described herein are capable of operating in other sequences than described or illustrated herein. Moreover, the terms "comprise", "have" and any variations thereof are intended to cover a non-exclusive inclusion, for example, a process, method, article, or apparatus that comprises a list of steps or units can not necessarily be limited to those steps or units, but can include additional steps or units not expressly listed or inherent to such process, method, article, or apparatus.

[0149] Optionally, the specific examples in the embodiments can refer to the examples described in the above embodiments, and the embodiments will not be described here again.

[0150] The serial numbers of the embodiments of the present application are only for description, not representing the advantages and disadvantages of the embodiments.

[0151] In the above-described embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0152] The above only describes the preferred embodiments of the present application, and it should be pointed out that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered as the protection scope of the present application.

Claims

1. A self-cleaning method for an air conditioner, characterized in that, The method includes: In response to the air conditioner's self-cleaning command, the air conditioner is operated in heating mode to at least reduce the surface temperature of the outdoor unit's heat exchanger. If the air conditioner has not entered defrost mode and has been running in heating mode for a preset time, determine whether the outdoor unit heat exchanger simultaneously meets a first condition and a second condition. The first condition is used to determine whether the temperature difference of the refrigerant within a certain time window meets a temperature threshold. The second condition is used to determine whether the current refrigerant is sufficient to cause frost formation on the outdoor unit heat exchanger. The refrigerant is the refrigerant in the outdoor unit heat exchanger, and the certain time window is within the preset time period. If the first and second conditions are met simultaneously, a preset defrosting program is invoked to defrost the outdoor unit of the air conditioner. After the defrosting process is completed, the fan controlling the outdoor unit of the air conditioner reverses to at least blow away the melted water carrying dirt on the outdoor unit's heat exchanger. After the step of operating the air conditioner in heating mode and before the step of determining whether the outdoor unit simultaneously meets the first condition and the second condition, the method further includes: Determine whether the refrigerant's saturation temperature is less than or equal to the target saturation temperature; wherein, the target saturation temperature is used to measure whether the outdoor unit's heat exchanger is tending towards frosting; wherein, when the refrigerant's saturation temperature is less than or equal to the target saturation temperature, it indicates that the outdoor unit's heat exchanger is tending towards frosting or has already frosted. If the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, determine whether the air conditioner is in defrosting mode. If the refrigerant saturation temperature is greater than the target saturation temperature, after increasing the power consumption of the air conditioner compressor and running it continuously for several minutes, it is then determined whether the refrigerant saturation temperature is less than or equal to the target saturation temperature. Specifically, after determining whether the air conditioner is in defrosting mode, the method further includes: If the air conditioner is not in a defrosting state, determine whether the air conditioner has been running in heating mode for a preset time. If the preset running time has not been accumulated, the air conditioner continues to run in heating mode, and within the preset time, it is determined in real time or periodically whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature. If the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, it is further determined whether the air conditioner has entered the defrosting state.

2. The method according to claim 1, characterized in that, The first condition is used to determine whether the temperature difference in the decrease of the refrigerant's saturation temperature within a certain time window meets the temperature threshold; the second condition is used to determine whether the current saturation temperature of the refrigerant is sufficient to cause the outdoor unit's heat exchanger to frost.

3. The method according to claim 1, characterized in that, The step of calling a preset defrosting program to defrost the outdoor unit of the air conditioner includes: During the defrosting process, when the defrosting temperature is detected to be above zero degrees Celsius, the fan of the outdoor unit of the air conditioner is controlled to reverse to blow away the loose frost or ice layer carrying dirt.

4. The method according to claim 1, characterized in that, If the first condition and / or the second condition are not met, the method further includes: Directly control the fan of the outdoor unit of the air conditioner to reverse so as to blow away at least the condensate carrying dirt from the heat exchanger of the outdoor unit.

5. The method according to claim 1, characterized in that, Before the step of determining whether the saturation temperature of the refrigerant is less than or equal to the target saturation temperature, the method further includes: Control the outdoor unit fan of the air conditioner to reverse at maximum speed for initial cleaning.

6. The method according to claim 5, characterized in that, After the step of controlling the outdoor unit fan of the air conditioner to reverse at maximum speed for preliminary cleaning, and before the step of determining whether the refrigerant saturation temperature is less than or equal to the target saturation temperature, the method further includes: Detect the current outdoor temperature; The target saturation temperature is determined based on the current outdoor temperature and the preset target saturation temperature setting rules.

7. The method according to claim 1, characterized in that, Prior to the step of operating the air conditioner in heating mode to at least reduce the surface temperature of the outdoor unit heat exchanger, the method further includes: Based on a preset set of rules for identifying dirt and blockage in the outdoor unit of an air conditioner, the system identifies whether the outdoor unit of the air conditioner is dirty or blocked. The set of rules for identifying dirt and blockage in the outdoor unit of an air conditioner includes at least the following rules: if the pressure difference across the heat exchanger of the outdoor unit reaches a pressure difference threshold and the speed of the outdoor unit fan is lower than a speed threshold, the outdoor unit of the air conditioner is identified as dirty or blocked. If dirt or blockage is detected in the outdoor unit of the air conditioner, a self-cleaning instruction or a self-cleaning request for the air conditioner is generated; wherein, the request is sent to the user and is used to instruct the generation of the self-cleaning instruction for the air conditioner.

8. An electronic device, characterized in that, include: A memory, and one or more processors communicatively connected to the memory; The memory stores instructions that can be executed by the one or more processors to cause the one or more processors to implement the method as described in any one of claims 1 to 7.

9. An air conditioner, characterized in that, It employs the method according to any one of claims 1-7, or includes the electronic device as described in claim 8.

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