Control method for air conditioner

Abstract

The invention relates to the technical field of air conditioners, particularly provides a control method for an air conditioner, and aims to solve the problem of how to effectively delay frosting of an outdoor heat exchanger while reducing energy consumption. In order to achieve the purpose, according to the control method for the air conditioner, the dew-point temperature and the freezing-point temperature are determined through the outdoor environment temperature and the outdoor environment humidity, and then the spraying mechanism is controlled to spray the solution to the outdoor heat exchanger based on the surface temperature of the outdoor heat exchanger, the dew-point temperature and the freezing-point temperature. As the freezing point of the sprayed solution is smaller than that of water, the freezing point temperature of the surface of the outdoor heat exchanger can be reduced, frosting of the outdoor heat exchanger is effectively delayed, the heat exchange efficiency of the outdoor heat exchanger is ensured, and stable operation and the heating effect of the air conditioner are guaranteed. In addition, compared with an existing frosting delaying mode, the frosting time of the outdoor heat exchanger can be effectively delayed, a heating element does not need to be used, and energy consumption is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the field of air conditioners, and particularly provides a control method for an air conditioner. Background Art

[0002] When the air conditioner operates in heating mode for a long time in a low-temperature and high-humidity environment, the surface of the outdoor heat exchanger is prone to frosting, resulting in a significant decline in heat exchange performance. This not only affects the heating effect but also reduces the comfort of the indoor environment and the user experience. Currently, heating methods, thermal insulation methods, and hydrophobic surface treatment methods are usually used to delay the frosting of the outdoor heat exchanger. Among them, the heating method usually uses heating elements to keep the outdoor heat exchanger at a certain temperature. Although it can prevent the surface of the outdoor heat exchanger from frosting, the energy consumption is very high. The thermal insulation method usually covers the outdoor heat exchanger with thermal insulation materials to reduce heat dissipation. The hydrophobic surface treatment method is to treat the surface of the outdoor heat exchanger with hydrophobic or superhydrophobic materials to reduce the possibility of water vapor condensation. However, in actual applications, the effect of delaying frosting of these two methods is not ideal, and the surface of the heat exchanger is still prone to frosting, thereby affecting the heating effect of the air conditioner and the user experience.

[0003] Therefore, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0004] In order to solve at least one problem in the prior art, that is, to solve the problem of how to effectively delay the frosting of the outdoor heat exchanger while reducing energy consumption. For this purpose, the present application provides a control method for an air conditioner. The outdoor unit of the air conditioner includes an outdoor heat exchanger and a spraying mechanism. The freezing point of the solution sprayed by the spraying mechanism is less than the freezing point of water. The control method includes:

[0005] Obtain the outdoor ambient temperature, outdoor ambient humidity, and the first surface temperature of the outdoor heat exchanger;

[0006] Based on the outdoor ambient temperature and the outdoor ambient humidity, determine the dew point temperature and the freezing point temperature;

[0007] Compare the first surface temperature with the dew point temperature and the freezing point temperature respectively;

[0008] Based on the comparison results, selectively control the spraying of the solution from the spraying mechanism to the outdoor heat exchanger.

[0009] In a preferred technical solution of the above control method, the step of "based on the comparison results, selectively control the spraying of the solution from the spraying mechanism to the outdoor heat exchanger" further includes:

[0010] When the temperature of the first surface is less than the dew point temperature and greater than or equal to the freezing point temperature, control the spraying mechanism to spray a solution on the windward surface or the leeward surface of the outdoor heat exchanger; or

[0011] When the fan of the outdoor unit rotates forward, and the temperature of the first surface is less than the dew point temperature and greater than or equal to the freezing point temperature, control the spraying mechanism to spray a solution on the surface of the windward surface and the leeward surface that is away from the fan.

[0012] In a preferred technical solution of the above control method, after the step of controlling the spraying mechanism to spray a solution on the outdoor heat exchanger, the following steps are further included:

[0013] Obtain the temperature of the second surface of the outdoor heat exchanger again;

[0014] Compare the temperature of the second surface with the dew point temperature;

[0015] When the temperature of the second surface is greater than or equal to the dew point temperature, control the spraying mechanism to stop spraying.

[0016] In a preferred technical solution of the above control method, the control method further includes:

[0017] When the temperature of the first surface is less than the freezing point temperature, control the spraying mechanism to spray a solution on the windward surface and the leeward surface.

[0018] In a preferred technical solution of the above control method, after the step of "controlling the spraying mechanism to spray a solution on the windward surface and the leeward surface of the outdoor heat exchanger", the following steps are further included:

[0019] Obtain the temperature of the third surface of the outdoor heat exchanger again;

[0020] Compare the temperature of the third surface with the dew point temperature;

[0021] When the temperature of the third surface is greater than or equal to the dew point temperature, control the spraying mechanism to stop spraying.

[0022] In a preferred technical solution of the above control method, the outdoor unit further includes a cleaning mechanism. After the step of "controlling the spraying mechanism to stop spraying", the following steps are further included:

[0023] Control the cleaning mechanism to clean the spraying surface.

[0024] In a preferred technical solution of the above control method, after the step of "controlling the cleaning mechanism to clean the spraying surface", the following steps are further included:

[0025] Obtain the cleaning time of the cleaning mechanism;

[0026] Compare the cleaning time with the preset time;

[0027] When the cleaning time is greater than or equal to the preset time, control the cleaning mechanism to stop the cleaning work.

[0028] In a preferred technical solution of the above control method, before, after or at the same time as the step of "controlling the spraying mechanism to spray the solution on the windward surface and the leeward surface", the following steps are further included:

[0029] Control the fan of the outdoor unit to rotate in reverse and blow air to the outdoor heat exchanger.

[0030] In a preferred technical solution of the above control method, before, after or at the same time as the step of "controlling the cleaning mechanism to stop the cleaning work", the following steps are further included:

[0031] Control the fan to rotate forward.

[0032] In a preferred technical solution of the above control method, before the step of "acquiring the outdoor ambient temperature, the outdoor ambient humidity, and the first surface temperature of the outdoor heat exchanger", the following steps are further included:

[0033] The fan of the outdoor unit is in the forward rotation state.

[0034] Those skilled in the art can understand that the control method for the air conditioner of the present application determines the dew point temperature and the freezing point temperature through the outdoor ambient temperature and the outdoor ambient humidity, and then controls the spraying mechanism to spray the solution on the outdoor heat exchanger based on the comparison between the surface temperature of the outdoor heat exchanger and the dew point temperature and the freezing point temperature. Since the freezing point of the sprayed solution is lower than that of water, the freezing point temperature of the outdoor heat exchanger surface can be reduced, effectively delaying the frosting of the outdoor heat exchanger, thereby ensuring its heat exchange efficiency, guaranteeing the stable operation and heating effect of the air conditioner. In addition, compared with the existing methods for delaying frosting, the present application can effectively delay the frosting time of the outdoor heat exchanger and does not require the use of heating elements, significantly reducing energy consumption.

[0035] Further, when the surface temperature of the outdoor heat exchanger is less than the dew point temperature and greater than or equal to the freezing point temperature, by controlling the spraying mechanism to spray the solution on the windward surface or the leeward surface, the freezing point temperature of the outdoor heat exchanger surface can be reduced, delaying the frosting of the outdoor heat exchanger, thereby ensuring its heat exchange efficiency, guaranteeing the stable operation and heating effect of the air conditioner. In addition, when the fan rotates forward and the surface temperature of the outdoor heat exchanger is less than the dew point temperature and greater than or equal to the freezing point temperature, by controlling the spraying mechanism to spray the solution on the side of the windward surface and the leeward surface that is away from the fan, not only can the freezing point temperature of the outdoor heat exchanger surface be reduced, delaying the frosting of the outdoor heat exchanger, but also the solution can be prevented from being sucked into the fan to reduce the frosting delay effect and eliminate potential safety hazards.

[0036] Furthermore, when the second surface temperature of the outdoor heat exchanger is greater than or equal to the dew point temperature, unnecessary resource waste can be avoided by controlling the spraying mechanism to stop spraying.

[0037] Furthermore, when the first surface temperature is less than the freezing point temperature, by controlling the spraying mechanism to spray a solution on the outdoor heat exchanger, not only can the serious frosting problem of the outdoor heat exchanger be solved, but also the defrosting efficiency can be improved.

[0038] Furthermore, when the third surface temperature of the outdoor heat exchanger is greater than or equal to the dew point temperature, it indicates that the frost on the surface of the outdoor heat exchanger has basically melted. Unnecessary resource waste and problems that may be caused by excessive defrosting can be avoided by controlling the spraying mechanism to stop spraying.

[0039] Furthermore, after controlling the spraying mechanism to stop spraying, by controlling the cleaning mechanism to clean the residual solution on the spraying surface of the outdoor heat exchanger, the residual solution mixture can be effectively removed, the thermal resistance in the heat exchange process can be reduced, and thus the heat exchange efficiency can be improved.

[0040] Furthermore, before, after or simultaneously with spraying the solution on the windward surface and the leeward surface by the spraying mechanism, by controlling the fan to rotate in the reverse direction and blow air on the outdoor heat exchanger, the defrosting efficiency can be improved, and at the same time, the solution can be prevented from being sucked into the fan to reduce the defrosting effect and eliminate potential safety hazards.

[0041] Furthermore, after the cleaning mechanism completes the cleaning of the residual solution of the heat exchanger, by controlling the fan to rotate forward, the heating effect of the air conditioner can be effectively improved. Description of the Drawings

[0042] The preferred embodiments of the present invention will be described below with reference to the drawings, in which:

[0043] Figure 1 is a flowchart of the control method for an air conditioner of the present application;

[0044] Figure 2 is a structural diagram of the outdoor heat exchanger of the present application;

[0045] Figure 3 is a logic diagram of a possible implementation manner of the control method for an air conditioner of the present application.

[0046] Description of the Reference Numerals:

[0047] 1. Outdoor heat exchanger; 2. Fan; 3. First spraying mechanism; 4. First cleaning mechanism; 41. Track; 42. Brush. Detailed Embodiments

[0048] The preferred embodiments of the present application will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principle of the present application and are not intended to limit the protection scope of the present application.

[0049] It should be noted that in the description of the present application, terms indicating directions or positional relationships such as "upper", "lower", "inner", "bottom", "end" are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0050] In addition, it should also be noted that in the description of the present application, unless otherwise clearly specified and defined, terms such as "arranged", "connected", "communicated" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0051] First, in combination with Figure 1-2 , the control method for an air conditioner of the present application will be introduced.

[0052] As Figure 2 shown, in order to solve the problem of effectively delaying the frosting of the outdoor heat exchanger while reducing energy consumption. The outdoor unit of the air conditioner of the present application includes an outdoor heat exchanger 1 and a spraying mechanism. The freezing points of the solutions sprayed by the spraying mechanism are all lower than the freezing point of water, which can reduce the freezing point temperature on the surface of the outdoor heat exchanger 1, effectively delay the frosting of the outdoor heat exchanger 1, and further ensure its heat exchange efficiency, and guarantee the stable operation and heating effect of the air conditioner

[0053] It should also be noted that there is no limitation on the spraying solution in the present application, as long as the freezing point temperature of the spraying solution is lower than the freezing point temperature of water. For example, the spraying solution can be ethanol.

[0054] Then refer to Figure 2 , the outdoor unit of the air conditioner includes a housing with an air inlet (not shown in the figure) and an outdoor heat exchanger 1, a spraying mechanism, a fan 2 and a cleaning mechanism arranged in the housing. One side of the outdoor heat exchanger 1 close to the air inlet is the windward side, and the side far from the air inlet is the leeward side. Among them, the windward side and the leeward side are arranged along the second direction on the outdoor heat exchanger (such as Figure 2On both sides of the shown Y direction). The fan 2 is located on the leeward side, and the fan 2 is configured to be able to rotate forward and backward. When the fan 2 rotates forward, air can flow through the outdoor heat exchanger 1 from the air inlet, improving the heat exchange effect of the outdoor heat exchanger 1. When the fan 2 rotates backward, the wind generated by the fan 2 can blow towards the outdoor heat exchanger 1, improving the defrosting effect. The cleaning mechanism is arranged on the outdoor heat exchanger 1 for cleaning the outdoor heat exchanger 1 to reduce the increase in the thermal resistance of the outdoor heat exchanger 1 caused by solution residue and affect the heat exchange performance of the outdoor heat exchanger 1.

[0055] It should be noted that in the actual application process of the air conditioner, the windward side and the leeward side of the outdoor heat exchanger 1 mainly serve as heat exchange surfaces. Therefore, when defrosting or delaying frosting operations are carried out, these two surfaces are mainly targeted. Among them, in order to facilitate spraying the solution on the windward side and the leeward side of the outdoor heat exchanger 1, the spraying mechanism of the present application may include a first spraying mechanism 3 and a second spraying mechanism. In order to facilitate the cleaning work on the windward side and the leeward side of the outdoor heat exchanger 1, the cleaning mechanism includes a first cleaning mechanism 4 and a second cleaning mechanism. Specifically, as Figure 2 shown, the first spraying mechanism 3 and the first cleaning mechanism 4 (not shown in the figure) are both arranged on the windward side of the outdoor heat exchanger 1. The first spraying mechanism 3 is used for spraying the windward side of the outdoor heat exchanger 1, and the first cleaning mechanism 4 is used for cleaning the windward side of the outdoor heat exchanger 1. The second spraying mechanism and the second cleaning mechanism are both arranged on the leeward side of the outdoor heat exchanger 1. The second spraying mechanism is used for spraying the leeward side of the outdoor heat exchanger 1, and the second cleaning mechanism is used for cleaning the leeward side of the outdoor heat exchanger 1.

[0056] Of course, the setting position of the fan 2 in the present application is not fixed, and those skilled in the art can adjust it according to needs. For example, the fan 2 can also be located on the windward side. At this time, when the fan 2 rotates backward, the wind generated by the fan 2 can blow towards the outdoor heat exchanger 1.

[0057] Then refer to Figure 2 , the first spraying mechanism 3 is arranged on the windward side and close to the first side of the outdoor heat exchanger 1 in the third direction (such as Figure 2 shown in the X direction), which is beneficial for the first spraying mechanism 3 to spray the solution on the windward side. The first cleaning mechanism 4 includes a track 41 arranged on the windward side and a brush 42 slidably arranged on the track 41. The track 41 extends along the first direction and is close to the second side of the outdoor heat exchanger 1 in the third direction. The brush 42 extends along the second direction (such as Figure 2 shown in the Y direction) and can be in contact with the windward side, so that when the brush 42 moves along the track 41 in the first direction (such as Figure 2 shown in the Z direction), the brush 42 can clean the windward side. Among them, the first direction, the second direction, and the third direction are perpendicular to each other pairwise.

[0058] Among them, the structure of the second spraying mechanism is the same as that of the first spraying mechanism 3, and the structure of the second cleaning mechanism is the same as that of the first cleaning mechanism 4. Therefore, the second spraying mechanism and the second cleaning mechanism will not be elaborated here. Although the structure of the second spraying mechanism is the same as that of the first spraying mechanism 3, the second spraying mechanism can be arranged on the leeward surface and close to the first side of the outdoor heat exchanger 1 in the third direction. At this time, the track 41 of the second cleaning mechanism is arranged on the leeward surface and close to the second side of the outdoor heat exchanger 1 in the third wind direction; or the second spraying mechanism can also be arranged on the leeward surface and close to the second side of the outdoor heat exchanger 1 in the third direction. At this time, the track 41 of the second cleaning mechanism is arranged on the leeward surface and close to the first side of the outdoor heat exchanger 1 in the third wind direction.

[0059] The positions of the first spraying mechanism 3 and the second spraying mechanism in this application are not fixed, as long as the first spraying mechanism 3 can spray the solution onto the windward surface. For example, the first spraying mechanism 3 can be arranged on the first side of the outdoor heat exchanger 1 along the third direction, and / or the second spraying mechanism can also be arranged on the second side of the outdoor heat exchanger 1 along the third direction; or the first spraying mechanism 3 can also be arranged on the housing and on one side of the windward surface, and / or the second spraying mechanism can also be arranged on the housing and on one side of the leeward surface.

[0060] As Figure 1 shown, based on the above setting method, the control method for an air conditioner in this application includes:

[0061] S101. Obtain the outdoor ambient temperature, outdoor ambient humidity, and the first surface temperature of the outdoor heat exchanger 1. For example, the outdoor ambient temperature and outdoor ambient humidity are obtained by setting temperature sensors and humidity sensors on the outdoor unit; the first surface temperature of the outdoor heat exchanger 1 is obtained by setting temperature sensors on the surface of the outdoor heat exchanger 1.

[0062] S102. Determine the dew point temperature and the freezing point temperature based on the outdoor ambient temperature and outdoor ambient humidity. For example, after obtaining the outdoor ambient temperature and outdoor ambient humidity, the dew point temperature is determined based on the first comparison relationship between the outdoor ambient temperature and outdoor ambient humidity and the dew point temperature, such as a comparison table, empirical formula, or fitting formula. The freezing point temperature of the outdoor heat exchanger 1 is determined based on the second comparison relationship between the outdoor ambient temperature and outdoor ambient humidity and the freezing point temperature, such as a comparison table, empirical formula, or fitting formula.

[0063] S103. Compare the first surface temperature with the dew point temperature and the freezing point temperature respectively. For example, after determining the dew point temperature and the freezing point temperature, compare the magnitudes of the two by comparing whether the differences between the surface temperature and the dew point temperature, and the surface temperature and the freezing point temperature are greater than or equal to 0, or whether the ratios between the two are greater than or equal to 1, so as to determine the magnitudes of the surface temperature and the dew point temperature, and the surface temperature and the freezing point temperature respectively.

[0064] S104. Based on the comparison results, selectively control the spraying of the solution to the outdoor heat exchanger 1 in the spraying mechanism. For example, after determining the magnitudes of the surface temperature and the dew point temperature, and the freezing point temperature, the spraying of the solution to the outdoor heat exchanger 1 in the spraying mechanism can be controlled.

[0065] In this application, the dew point temperature and the freezing point temperature are determined through the outdoor ambient temperature and the outdoor ambient humidity, and then based on the magnitudes of the surface temperature of the outdoor heat exchanger 1 and the dew point temperature and the freezing point temperature, the spraying mechanism is controlled to spray the solution to the outdoor heat exchanger 1. Since the freezing point of the sprayed solution is lower than that of water, the freezing point temperature of the surface of the outdoor heat exchanger 1 can be reduced, effectively delaying the frosting of the outdoor heat exchanger 1, thereby ensuring its heat exchange efficiency and guaranteeing the stable operation and heating effect of the air conditioner. In addition, compared with the existing methods for delaying frosting, this application can effectively delay the frosting time of the outdoor heat exchanger 1 and does not require the use of heating elements, greatly reducing energy consumption.

[0066] The preferred embodiments of the control method for the air conditioner of this application are introduced below.

[0067] In one embodiment, before the step of "obtaining the outdoor ambient temperature, the outdoor ambient humidity, and the first surface temperature of the outdoor heat exchanger", it further includes:

[0068] The fan of the outdoor unit is in the forward rotation state.

[0069] It should be noted that it is described with the fan 2 usually located on one side of the leeward surface of the outdoor heat exchanger. Before delaying the frosting or defrosting of the outdoor heat exchanger 1, in order to improve the heat exchange effect of the outdoor heat exchanger 1, the fan rotates forward when the air conditioner starts, so that the air can flow through the outdoor heat exchanger 1 from the air inlet, improving the heat exchange effect of the outdoor heat exchanger 1. When the fan 2 is located on one side of the windward surface of the outdoor heat exchanger 1, the fan can also rotate forward when the air conditioner starts, but the heat exchange efficiency of the outdoor heat exchanger 1 is lower than that when the fan is located on one side of the leeward surface of the outdoor heat exchanger 1.

[0070] In one embodiment, the step of "selectively controlling the spraying of the solution to the outdoor heat exchanger 1 in the spraying mechanism" based on the comparison results further includes:

[0071] When the first surface temperature is less than the dew point temperature and greater than or equal to the freezing point temperature, the spraying mechanism is controlled to spray a solution onto the windward side or the leeward side of the outdoor heat exchanger.

[0072] It should be noted that usually the freezing point temperature is less than the dew point temperature. Therefore, when the first surface temperature is less than the freezing point temperature, the first surface temperature must also be less than the dew point temperature. In addition, the surface temperature of the outdoor heat exchanger 1 can be the temperature of the windward side, the temperature of the leeward side, or the average of the temperatures of the windward side and the leeward side, which can be selected by those skilled in the art according to needs.

[0073] It should also be noted that when the surface temperature of the outdoor heat exchanger 1 is less than the dew point temperature and greater than or equal to the freezing point temperature, frosting is likely to occur on the surface of the outdoor heat exchanger 1. To effectively delay frosting, the spraying mechanism can be controlled to spray a solution onto the windward side or the leeward side of the outdoor heat exchanger 1 to lower the freezing point temperature of the outdoor heat exchanger 1. In addition, since frosting has not occurred on the outdoor heat exchanger 1 yet, it is not necessary to spray the solution onto both the windward side and the leeward side at the same time. It is only necessary to spray the solution onto one of the windward side and the leeward side, so as to avoid unnecessary resource waste while delaying frosting. In addition, this step is carried out under the condition that the fan is not started when the air conditioner is in operation.

[0074] For example, taking the dew point temperature as 2°C, the freezing point temperature as 0°C, the first surface temperature as the windward side temperature, and the spraying mechanism including the first spraying mechanism 3 and the second spraying mechanism for illustration. When the windward side temperature is less than 2°C and greater than or equal to 0°C, since the leeward side is usually in a similar environmental condition to the windward side, the temperatures of the windward side and the leeward side are basically similar. It can be considered that the surface temperature of the outdoor heat exchanger 1 is between the dew point temperature and the freezing point temperature. At this time, frosting is likely to occur on the surface of the outdoor heat exchanger 1. To avoid frosting on the surface of the outdoor heat exchanger 1 and delay the frosting time of the outdoor heat exchanger 1, the first spraying mechanism 3 can be controlled to spray a solution onto the windward side, or the second spraying mechanism can be controlled to spray a solution onto the leeward side, which can lower the freezing point temperature at which frosting occurs on the outdoor heat exchanger 1 and delay frosting.

[0075] In one embodiment, the step of "selectively controlling the spraying mechanism to spray a solution onto the outdoor heat exchanger 1 based on the comparison result" further includes:

[0076] When the fan 2 rotates forward and the first surface temperature is less than the dew point temperature and greater than or equal to the freezing point temperature, the spraying mechanism is controlled to spray a solution onto the side of the windward side and the leeward side that is away from the fan 2.

[0077] It should be noted that when the fan 2 rotates forward and is on the leeward side of the outdoor heat exchanger 1, air blows from the air inlet towards the outdoor heat exchanger 1. If the spraying mechanism sprays the solution onto the leeward side at this time, the solution can be sucked into the fan 2 to reduce and delay the frosting effect. Therefore, to prevent the solution from being sucked into the fan 2 and reducing the frosting delay effect, the spraying mechanism is controlled to spray the solution onto the windward side. When the fan 2 rotates forward and is on the windward side of the outdoor heat exchanger 1, air blows towards the air inlet. If the spraying mechanism sprays the solution onto the windward side at this time, the solution can be sucked into the fan 2 to reduce and delay the frosting effect. Therefore, to prevent the solution from being sucked into the fan 2 and reducing the frosting delay effect, the spraying mechanism is controlled to spray the solution onto the leeward side.

[0078] For example, taking the dew point temperature as 2°C, the freezing point temperature as 0°C, and the surface temperature of the outdoor heat exchanger as the windward surface temperature, and the spraying mechanism including the first spraying mechanism 3 and the second spraying mechanism, the fan 2 is located on the leeward side of the outdoor heat exchanger 1 for illustration. When the fan 2 rotates forward and the windward surface temperature is less than 2°C and greater than or equal to 0°C, it indicates that the surface temperature of the outdoor heat exchanger 1 is between the dew point temperature and the freezing point temperature. At this time, frosting is likely to occur on the surface of the outdoor heat exchanger 1. To avoid frosting on the surface of the outdoor heat exchanger 1 and the solution being sucked into the fan 2 to reduce the frosting delay effect, the first spraying mechanism 3 can be controlled to spray the solution onto the windward side, which can lower the freezing point temperature of the outdoor heat exchanger 1 where frosting occurs and delay frosting.

[0079] In one implementation, after the step of controlling the spraying mechanism to spray the solution onto the outdoor heat exchanger 1, it further includes:

[0080] Obtain the second surface temperature of the outdoor heat exchanger 1 again;

[0081] Compare the magnitude of the second surface temperature and the dew point temperature;

[0082] When the second surface temperature is greater than or equal to the dew point temperature, then control the spraying mechanism to stop the spraying operation.

[0083] It should be noted that after the spraying mechanism sprays the solution onto the surface of the outdoor heat exchanger 1, the freezing point temperature of the surface of the outdoor heat exchanger 1 will be reduced. Therefore, the surface temperature of the outdoor heat exchanger 1 will change. So, it is necessary to obtain the temperature of the surface of the outdoor heat exchanger 1 again.

[0084] Among them, both the first surface temperature and the second surface temperature refer to the surface temperature of the outdoor heat exchanger 1. To facilitate the distinction of the temperature of the outdoor heat exchanger 1 at different step nodes, the first surface temperature and the second surface temperature are used to represent it. Among them, both the second surface temperature and the first surface temperature are used to refer to the temperature of the same side of the outdoor heat exchanger 1. For example, if the first surface temperature is the average value of the windward surface temperature and the leeward surface temperature, then the second surface temperature is also the average value of the windward surface temperature and the leeward surface temperature. Or if the first surface temperature is the temperature of the windward surface, then the second surface temperature is also the temperature of the windward surface. Or if the first surface temperature is the temperature of the leeward surface, then the second surface temperature is also the temperature of the leeward surface.

[0085] Illustrate with an example. Taking the dew point temperature as 2°C and the second spraying mechanism spraying the solution on the leeward surface for explanation. When the second surface temperature is greater than or equal to 2°C, it indicates that the second surface temperature exceeds the dew point temperature, meaning that frosting will not occur on the surface of the outdoor heat exchanger 1. In this case, the second spraying mechanism can be controlled to stop spraying to avoid unnecessary resource waste and problems that may be caused by overly delaying frosting. On the contrary, when the second surface temperature is less than 2°C, it indicates that there is still a risk of frosting on the outdoor heat exchanger 1. Therefore, it is necessary to maintain the second spraying mechanism to continue spraying the solution on the surface of the outdoor heat exchanger 1.

[0086] Illustrate with an example. Taking the dew point temperature as 2°C and the first spraying mechanism 3 spraying the solution on the windward surface for explanation. When the second surface temperature is greater than or equal to 2°C, it indicates that the second surface temperature exceeds the dew point temperature, meaning that frosting will not occur on the surface of the outdoor heat exchanger 1. In this case, the first spraying mechanism 3 can be controlled to stop spraying to avoid unnecessary resource waste and problems that may be caused by overly delaying frosting. On the contrary, when the second surface temperature is less than 2°C, it indicates that there is still a risk of frosting on the outdoor heat exchanger 1. Therefore, it is necessary to maintain the first spraying mechanism 3 to continue spraying the solution on the surface of the outdoor heat exchanger 1.

[0087] In one embodiment, the outdoor unit further includes a cleaning mechanism. After the step of "controlling the spraying mechanism to stop spraying", the following steps are also included:

[0088] Control the cleaning mechanism to clean the spraying surface.

[0089] Illustrate with an example. Taking the spraying mechanism including the first spraying mechanism 3 and the second spraying mechanism, the spraying surface being the windward surface, and the cleaning mechanism including the first cleaning mechanism 4 and the second cleaning mechanism for explanation. After the first spraying mechanism 3 stops spraying, control the first cleaning mechanism 4 to clean the windward surface.

[0090] Furthermore, after the step of "controlling the cleaning mechanism to clean the spraying surface of the outdoor heat exchanger 1", the following steps are also included:

[0091] Obtain the first cleaning time of the cleaning mechanism;

[0092] Compare the magnitude of the first cleaning time and the first preset time;

[0093] When the first cleaning time is greater than or equal to the first preset time, control the cleaning mechanism to stop the cleaning work.

[0094] For example, taking the first preset time as 5 minutes, the cleaning mechanism includes a first cleaning mechanism 4 and a second cleaning mechanism, and the spraying surface is the windward surface for illustration. After the first cleaning mechanism 4 cleans the windward surface of the outdoor heat exchanger 1, obtain the first cleaning time of the first cleaning mechanism 4. When the first cleaning time is greater than or equal to 5 minutes, it indicates that the first cleaning mechanism 4 has reached the preset cleaning time. At this time, control the first cleaning mechanism 4 to stop working, so as to ensure that the surface of the outdoor heat exchanger 1 is fully cleaned, and at the same time avoid waste of resources or unnecessary wear caused by excessive operation of the cleaning mechanism.

[0095] In one implementation, the control method further includes:

[0096] When the first surface temperature is less than the freezing point temperature, control the spraying mechanism to spray the solution on the windward surface and the leeward surface.

[0097] For example, taking the dew point temperature as 2°C, the freezing point temperature as 0°C, and the first surface temperature as the average of the windward surface and leeward surface temperatures, and the spraying mechanism includes a first spraying mechanism 3 and a second spraying mechanism for illustration. When the first surface temperature is less than 0°C, it indicates that the average of the windward surface and leeward surface temperatures is less than the freezing point temperature. Since the leeward surface is usually in a similar environmental condition as the windward surface, the temperatures of the windward surface and the leeward surface are basically similar. Therefore, it can be considered that the temperatures of both the windward surface and the leeward surface are less than the freezing point temperature. In this case, the water vapor in the air will solidify into frost on the surface of the outdoor heat exchanger 1 (leeward surface and windward surface). Therefore, control the first spraying mechanism 3 to spray the solution on the windward surface, and the second spraying mechanism to spray the solution on the leeward surface. Since the freezing point of the solution is lower than that of water, the solution can still remain liquid below the freezing point temperature, so that the frost can absorb the heat of the solution and melt, thereby achieving the defrosting effect.

[0098] Another example is given. Taking the dew point temperature as 2°C, the freezing point temperature as 0°C, and the first surface temperature as the windward surface temperature, the spraying mechanism includes a first spraying mechanism 3 and a second spraying mechanism for illustration. When the windward surface temperature is less than 0°C, since the leeward surface is usually in a similar environmental condition as the windward surface, the temperatures of the windward surface and the leeward surface are basically similar. Therefore, it can be considered that the temperature of the leeward surface is also less than the freezing point temperature. At this time, the water vapor in the air will solidify into frost on the windward surface, and frosting is likely to occur or has already occurred on the leeward surface. At this time, controlling the first spraying mechanism 3 to spray a solution on the windward surface can remove the frost on the windward surface, and the second spraying mechanism spraying a solution on the leeward surface can solve the problem of reducing the freezing point temperature of the leeward surface and delaying frosting under the condition that frosting is likely to occur on the leeward surface, and can also solve the problem that frosting has already occurred on the leeward surface.

[0099] Another example is given. Taking the dew point temperature as 2°C, the freezing point temperature as 0°C, and the first surface temperature as the temperature of the leeward surface, the spraying mechanism includes a first spraying mechanism 3 and a second spraying mechanism for illustration. When the temperature of the leeward surface is less than 0°C, that is, when the temperature of the leeward surface is less than the freezing point temperature, the temperature of the windward surface must also be less than the freezing point temperature. At this time, the water vapor in the air will solidify into frost on both the windward surface and the leeward surface. At this time, controlling the first spraying mechanism 3 to spray a solution on the windward surface and the second spraying mechanism to spray on the leeward surface can remove the frost on the surfaces of both.

[0100] Further, after the step of "controlling the spraying mechanism to spray a solution on the windward surface and the leeward surface of the outdoor heat exchanger 1", the following steps are also included:

[0101] Obtain the third surface temperature of the outdoor heat exchanger 1 again;

[0102] Compare the magnitude of the third surface temperature and the dew point temperature;

[0103] When the third surface temperature is greater than or equal to the dew point temperature, then control the spraying mechanism to stop the spraying operation.

[0104] It should be noted that after the spraying mechanism sprays a solution on the surface of the outdoor heat exchanger 1, the frost on the surface of the outdoor heat exchanger 1 will absorb the heat of the solution and melt, so the temperature of the surface of the outdoor heat exchanger 1 increases. Therefore, it is necessary to obtain the surface temperature of the outdoor heat exchanger 1 again.

[0105] Among them, both the first surface temperature and the third surface temperature refer to the surface temperature of the outdoor heat exchanger 1. To facilitate the distinction of the temperature of the outdoor heat exchanger 1 at different step nodes, the first surface temperature and the third surface temperature are used to represent it. Among them, both the third surface temperature and the first surface temperature are used to refer to the temperature of the same side of the outdoor heat exchanger 1. For example, if the first surface temperature is the average of the windward surface and the leeward surface temperatures, then the third surface temperature is also the average of the windward surface and the leeward surface temperatures. Or if the first surface temperature is the temperature of the windward surface, then the third surface temperature is also the temperature of the windward surface. Or if the first surface temperature is the temperature of the leeward surface, then the third surface temperature is also the temperature of the leeward surface.

[0106] For example, taking the dew point temperature as 2°C and the third surface temperature as the average of the windward surface and the leeward surface temperatures, and the spraying mechanism includes the first spraying mechanism 3 and the second spraying mechanism for illustration. Since the leeward surface is usually in similar environmental conditions as the windward surface, the temperatures of the windward surface and the leeward surface are basically similar. Therefore, when the third surface temperature is greater than or equal to 2°C, it can be considered that the temperatures of both the windward surface and the leeward surface exceed the dew point temperature. In this case, the frost on the surface of the outdoor heat exchanger 1 has basically melted. Therefore, the first spraying mechanism 3 and the second spraying mechanism can be controlled to stop the spraying operation to avoid unnecessary resource waste and problems that may be caused by excessive defrosting. On the contrary, when the second surface is less than 2°C, it can be considered that the temperatures of both the windward surface and the leeward surface do not exceed the dew point temperature, indicating that the frost has not completely melted. To ensure that the frost can be effectively removed, it is necessary to maintain the first spraying mechanism 3 and the second spraying mechanism to continue spraying the solution on the surface of the outdoor heat exchanger 1.

[0107] For example, taking the dew point temperature as 2°C and the third surface temperature as the temperature of the windward surface, and the spraying mechanism includes the first spraying mechanism 3 and the second spraying mechanism for illustration. When the third surface temperature is greater than or equal to 2°C, it indicates that the temperature of the windward surface exceeds the dew point temperature. Since the leeward surface is usually in similar environmental conditions as the windward surface, it can be considered that the temperature of the leeward surface is also greater than or equal to the dew point temperature. In this case, the frost on the surface of the outdoor heat exchanger 1 has melted. Therefore, the first spraying mechanism 3 and the second spraying mechanism can be controlled to stop the spraying operation to avoid unnecessary resource waste and problems that may be caused by excessive defrosting. On the contrary, when the temperature of the windward surface is less than 2°C, it can be considered that the temperature of the leeward surface is also less than 2°C, indicating that the surface temperature of the outdoor heat exchanger 1 is still relatively low and the frost has not been completely removed. Therefore, to ensure that the frost can be effectively removed, it is necessary to maintain the first spraying mechanism 3 and the second spraying mechanism to continue spraying the solution on the surface of the outdoor heat exchanger 1.

[0108] For example, taking the dew point temperature as 2°C, the third surface temperature as the leeward surface temperature, and the spraying mechanism including the first spraying mechanism 3 and the second spraying mechanism for illustration. Since the windward surface is usually in similar environmental conditions to the leeward surface, it can be inferred that the temperature of the windward surface is basically similar to that of the leeward surface. Then, when the leeward surface temperature is greater than or equal to 2°C, it can be considered that the temperature of the windward surface also exceeds the dew point temperature. In this case, the frost on the surface of the outdoor heat exchanger 1 has basically melted. Therefore, the first spraying mechanism 3 and the second spraying mechanism can be controlled to stop the spraying operation to avoid unnecessary resource waste and problems that may be caused by excessive defrosting. On the contrary, when the leeward surface temperature is less than 2°C, it can be considered that the windward surface temperature is also less than 2°C, indicating that the surface temperature of the outdoor heat exchanger 1 is still relatively low and the frost has not been completely removed. Therefore, to ensure that the frost can be effectively removed, it is necessary to maintain the first spraying mechanism 3 and the second spraying mechanism to continue spraying the solution on the surface of the outdoor heat exchanger 1.

[0109] In one embodiment, the outdoor unit further includes a cleaning mechanism. After the step of "controlling the spraying mechanism to stop the spraying operation", the following steps are further included:

[0110] Controlling the cleaning mechanism to clean the windward surface and the leeward surface.

[0111] It should be noted that after the spraying mechanism stops the spraying operation, a mixture of solution, water, and dust often remains on the windward surface and the leeward surface of the outdoor heat exchanger 1. These residues will increase the thermal resistance of the outdoor heat exchanger 1 and reduce the heat exchange effect of the outdoor heat exchanger 1. Therefore, it is necessary to use the cleaning mechanism to clean the windward surface and the leeward surface to ensure the cleanliness of its surface.

[0112] For example, taking the spraying mechanism including the first spraying mechanism 3 and the second spraying mechanism, and the cleaning mechanism including the first cleaning mechanism 4 and the second cleaning mechanism for illustration. After the first spraying mechanism 3 and the second spraying mechanism stop the spraying operation, control the first cleaning mechanism 4 to clean the windward surface and the second cleaning mechanism to clean the leeward surface.

[0113] Further, after the step of "controlling the cleaning mechanism to clean the windward surface and the leeward surface", the following steps are further included:

[0114] Obtaining the second cleaning time of the cleaning mechanism;

[0115] Comparing the second cleaning time with the second preset time;

[0116] When the second cleaning time is greater than or equal to the second preset time, then control the cleaning mechanism to stop the cleaning operation.

[0117] For example, taking the second preset time as 10 minutes, the cleaning mechanism includes a first cleaning mechanism 4 and a second cleaning mechanism for illustration. After the first cleaning mechanism 4 and the second cleaning mechanism clean the surface of the outdoor heat exchanger 1, the second cleaning time of the first cleaning mechanism 4 and the second cleaning mechanism is obtained. When the second cleaning time is greater than or equal to 10 minutes, it indicates that the two cleaning mechanisms have reached the preset cleaning time. At this time, the two cleaning mechanisms are controlled to stop the cleaning work, so as to ensure that the surface of the outdoor heat exchanger 1 is fully cleaned, and at the same time avoid resource waste or unnecessary wear caused by excessive operation of the cleaning mechanism.

[0118] In one implementation, before, after or at the same time as the step of "controlling the spraying mechanism to spray the solution on the windward surface and the leeward surface", the following steps are further included:

[0119] Control the fan 2 to rotate in the reverse direction to blow air to the outdoor heat exchanger 1.

[0120] It should be noted that when the air conditioner is in the heating mode and the fan 2 is on one side of the leeward surface, if the fan 2 is rotated in the reverse direction to blow air to the outdoor heat exchanger 1, although the heating effect may be slightly reduced, overall it will not have a substantial impact on the heating demand of the user.

[0121] For example, taking the fan 2 rotating forward when the air conditioner starts the heating mode, and the spraying mechanism includes a first spraying mechanism 3 and a second spraying mechanism for illustration. When the first spraying mechanism 3 and the second spraying mechanism spray the solution on the windward surface and the leeward surface of the outdoor heat exchanger 1 respectively, in order to prevent the solution from being sucked into the fan 2 and reducing the defrosting effect, the fan 2 can be controlled to rotate in the reverse direction before or at the same time as controlling the first spraying mechanism 3 and the second spraying mechanism to spray the solution on the outdoor heat exchanger 1, so that the air blows to the outdoor heat exchanger to improve the defrosting efficiency. In addition, after the fan 2 rotates forward and the spraying mechanism sprays the solution on the outdoor heat exchanger 1, if the fan 2 is quickly controlled to rotate in the reverse direction, since the time is short and the fan 2 will rotate in the reverse direction subsequently, this process will not affect the fan 2. Therefore, the fan 2 can also be controlled to rotate in the reverse direction after controlling the first spraying mechanism 3 and the second spraying mechanism to spray the solution on the outdoor heat exchanger 1.

[0122] Another example, taking the fan 2 not running when the air conditioner starts the heating mode, and the spraying mechanism includes a first spraying mechanism 3 and a second spraying mechanism for illustration. Since the fan 2 is not running, there is no need to consider the solution being sucked into the fan 2 and reducing the defrosting effect. Therefore, the fan 2 can be controlled to rotate in the reverse direction before, after or at the same time as the first spraying mechanism 3 and the second spraying mechanism spray the solution on the windward surface and the leeward surface of the outdoor heat exchanger 1, so that the air blows to the outdoor heat exchanger to improve the defrosting efficiency.

[0123] Furthermore, before, after or at the same time as the step of "controlling the cleaning mechanism to stop the cleaning work", the following steps are further included:

[0124] Control the fan 2 to rotate forward.

[0125] It should be noted that when the cleaning mechanism stops cleaning, it means that the defrosting work on the outdoor heat exchanger 1 has been completed. At this time, if the fan 2 is on the leeward side, controlling the fan 2 to rotate forward can improve the heat exchange efficiency of the outdoor heat exchanger 1, thereby enhancing the heating efficiency of the air conditioner.

[0126] The following will briefly describe Figure 3 a possible operation process of the control method for the air conditioner of the present application. Figure 3 It is a logic diagram of a possible implementation manner of the control method for the air conditioner of the present application.

[0127] S201. When the air conditioner operates in the heating mode, control the fan 2 on the leeward side to rotate forward, and then execute S202.

[0128] S202. Obtain the outdoor ambient temperature, outdoor ambient humidity, and the first surface temperature, and then execute S203.

[0129] S203. Based on the outdoor ambient temperature and outdoor ambient humidity, determine the dew point temperature and the freezing point temperature, and then execute S204.

[0130] S204. Determine whether the first surface temperature is ≥ 0°C? If yes, execute S205; otherwise, execute S214.

[0131] S205. Determine whether the first surface temperature is less than 2°C? If yes, execute S206; otherwise, execute S202.

[0132] S206. Control the first spraying mechanism 3 to spray the solution on the windward side of the outdoor heat exchanger 1, and then execute S207.

[0133] S207. Obtain the second surface temperature of the outdoor heat exchanger 1, and then execute S208.

[0134] S208. Determine whether the second surface temperature is greater than or equal to 2°C? If yes, execute S209; otherwise, execute S206.

[0135] S209. Control the first spraying mechanism 3 to stop spraying, and then execute S210.

[0136] S210. Control the first cleaning mechanism 4 to clean the windward side of the outdoor heat exchanger 1, and then execute S211.

[0137] S211. Obtain the first cleaning time of the first cleaning mechanism 4, and then execute S212.

[0138] S212. Determine whether the first cleaning time is greater than or equal to 5 minutes? If so, execute S213; otherwise, execute S210.

[0139] S213. Control the first cleaning mechanism 4 to stop the cleaning work, and then execute S202.

[0140] S214. Control the first spraying mechanism 3 and the second spraying mechanism to spray the solution on the windward side and the leeward side of the outdoor heat exchanger 1 simultaneously, and then execute S215.

[0141] S215. Control the fan 2 to rotate in the reverse direction to blow air towards the outdoor heat exchanger 1, and then execute S216.

[0142] S216. Obtain the third surface temperature of the outdoor heat exchanger 1, and then execute S217.

[0143] S217. Determine whether the third surface temperature is greater than or equal to 2°C? If so, execute S218; otherwise, execute S214.

[0144] S218. Control the first spraying mechanism 3 and the second spraying mechanism to stop the spraying work, and then execute S219.

[0145] S219. Control the first cleaning mechanism 4 and the second cleaning mechanism to clean the windward side and the leeward side of the outdoor heat exchanger 1, and then execute S220.

[0146] S220. Obtain the second cleaning time of the first cleaning mechanism 4 and the second cleaning mechanism, and then execute S221.

[0147] S221. Determine whether the second cleaning time is greater than or equal to 10 minutes? If so, execute S222; otherwise, execute S219.

[0148] S222. Control the first cleaning mechanism 4 and the second cleaning mechanism to stop the cleaning work, and then execute S223.

[0149] S223. Control the fan 2 to rotate in the forward direction, and then execute S202.

[0150] Those skilled in the art can understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the claims of the present application, any one of the claimed embodiments can be used in any combination.

[0151] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principle of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A control method for an air conditioner, characterized in that, The outdoor unit of the air conditioner includes an outdoor heat exchanger and a spray mechanism, the freezing point of the solution sprayed by the spray mechanism is lower than the freezing point of water, and the control method includes: Acquiring outdoor ambient temperature, outdoor ambient humidity, and a first surface temperature of the outdoor heat exchanger; Determining a dew point temperature and a freezing point temperature based on the outdoor ambient temperature and the outdoor ambient humidity; Comparing the first surface temperature with the dew point temperature and the freezing point temperature respectively; Based on the comparison result, the spray mechanism is selectively controlled to spray the solution toward the outdoor heat exchanger.

2. The control method according to claim 1, characterized in that, The step of "selectively controlling the spray mechanism to spray the solution to the outdoor heat exchanger based on the comparison result" further includes: When the first surface temperature is lower than the dew point temperature and greater than or equal to the freezing point temperature, the spray mechanism is controlled to spray the solution onto the windward surface or the leeward surface of the outdoor heat exchanger; or When the fan of the outdoor unit rotates forward and the first surface temperature is less than the dew point temperature and greater than or equal to the freezing point temperature, the spray mechanism is controlled to spray the solution onto one side of the windward surface and the leeward surface away from the fan.

3. The control method according to claim 2, wherein After the step of controlling the spray mechanism to spray the solution onto the outdoor heat exchanger, the step further includes: obtaining again a second surface temperature of the outdoor heat exchanger; comparing the second surface temperature with the dew point temperature; When the second surface temperature is greater than or equal to the dew point temperature, the spray mechanism is controlled to stop spraying.

4. The control method according to claim 2, wherein The control method further comprises: When the first surface temperature is lower than the freezing point temperature, the spray mechanism is controlled to spray the solution toward the windward surface and the leeward surface.

5. The control method according to claim 4, characterized in that After the step of "controlling the spray mechanism to spray the solution onto the windward side and the leeward side of the outdoor heat exchanger", the step further includes: obtaining again a third surface temperature of the outdoor heat exchanger; comparing the third surface temperature with the dew point temperature; When the third surface temperature is greater than or equal to the dew point temperature, the spray mechanism is controlled to stop spraying.

6. The control method according to claim 3 or 5, characterized in that, The outdoor unit further includes a cleaning mechanism, and after the step of "controlling the spray mechanism to stop spraying", the step further includes: The cleaning mechanism is controlled to clean the spray surface.

7. The control method according to claim 6, wherein The step of "controlling the cleaning mechanism to clean the spray surface" also includes: Obtaining the cleaning time of the cleaning mechanism; Compare the cleaning time with the preset time; When the cleaning time is greater than or equal to a preset time, the cleaning mechanism is controlled to stop cleaning.

8. The control method according to claim 7, characterized in that Before, after or simultaneously with the step of "controlling the spray mechanism to spray the solution onto the windward surface and the leeward surface", the following steps may also be included: The fan of the outdoor unit is controlled to reverse and blow air to the outdoor heat exchanger.

9. The control method according to claim 8, wherein Before, after or simultaneously with the step of "controlling the cleaning mechanism to stop cleaning work", the following steps may also be included: The fan is controlled to rotate forward.

10. The control method according to claim 1, wherein Before the step of "obtaining the outdoor ambient temperature, the outdoor ambient humidity and the first surface temperature of the outdoor heat exchanger", the step further includes: The fan of the outdoor unit is in a forward rotation state.

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