Anti-freezing control method and anti-freezing control device for air conditioner and air conditioner

Abstract

The invention relates to the field of electric appliances, and provides an anti-freezing control method and device of an air conditioner and the air conditioner, an outdoor unit of the air conditioner is internally provided with a variable shunting outdoor heat exchanger, and the method comprises the steps that in a refrigeration mode, the indoor coil pipe temperature of an air conditioner compressor is obtained; based on the fact that the indoor coil pipe temperature meets the anti-freezing starting condition, the air conditioner is controlled to execute anti-freezing protection; and under the anti-freezing protection, the frequency of the compressor is controlled to be reduced, and the shunting mode of the outdoor heat exchanger is adjusted to reduce the number of shunting flow paths. The refrigerating capacity loss can be effectively compensated, freezing is prevented, meanwhile, the indoor temperature is kept stable, and the defect that safety and comfort are difficult to give consideration to in the related technology is overcome.

Description

Technical Field

[0001] This invention relates to the field of electrical technology, and in particular to an anti-freeze control method, an anti-freeze control device, and an air conditioner. Background Technology

[0002] In existing technologies, when air conditioners implement freeze protection in low-temperature and high-humidity environments, they typically prevent the indoor coil from freezing simply by reducing the compressor frequency or partially closing the electronic expansion valve. While such methods can mitigate the risk of freezing, they lead to a significant decrease in cooling capacity and a rise in indoor temperature, severely impacting user comfort. Furthermore, the control measures are limited to local components and do not consider the overall matching of the system circulation, which can easily cause energy efficiency deterioration. Summary of the Invention

[0003] This invention provides an anti-freezing control method, an anti-freezing control device, and an air conditioner to address the deficiencies in the prior art and achieve the following effects: effectively compensating for cooling capacity loss, maintaining stable indoor temperature while preventing freezing, and solving the problem of difficulty in balancing safety and comfort in related technologies.

[0004] In a first aspect, the present invention provides an anti-freezing control method for an air conditioner, wherein a variable flow outdoor heat exchanger is installed in the outdoor unit of the air conditioner, the method comprising: In cooling mode, the indoor coil temperature of the air conditioner compressor is obtained; Based on the indoor coil temperature meeting the anti-freeze start-up conditions, the air conditioner is controlled to perform anti-freeze protection. Under the anti-freeze protection, the frequency of the compressor is reduced, and the flow distribution mode of the outdoor heat exchanger is adjusted to reduce the number of flow distribution paths.

[0005] According to some embodiments of the present invention, under the anti-freeze protection, the steps of reducing the frequency of controlling the compressor and adjusting the flow distribution mode of the outdoor heat exchanger to reduce the number of flow distribution paths specifically include: The frequency of the compressor is controlled to decrease from the set frequency variation. Based on the set change frequency, the number of flow paths to be reduced in the outdoor heat exchanger is determined, and the flow distribution mode of the outdoor heat exchanger is adjusted according to the number of flow paths to be reduced.

[0006] According to some embodiments of the present invention, the step of determining the number of flow path reductions in the branch flow path of the outdoor heat exchanger based on the set change frequency specifically includes: When the set change frequency is less than the maximum frequency threshold and greater than or equal to the first change frequency, the number of flow paths reduced is determined to be the first reduction number; When the set change frequency is less than the first change frequency and greater than or equal to the second change frequency, the flow path reduction amount is determined to be the second reduction amount; If the set change frequency is less than the second change frequency and greater than or equal to the minimum frequency threshold, the flow path reduction amount is determined to be the third reduction amount; Among them, the first reduction is less than the total number of flow paths of the outdoor heat exchanger, the second reduction is less than the first reduction, and the third reduction is less than the second reduction but greater than or equal to 1.

[0007] According to some embodiments of the present invention, the step of determining the number of flow path reductions in the branch flow path of the outdoor heat exchanger based on the set change frequency specifically includes: When the set change frequency is greater than or equal to the maximum frequency threshold, the number of flow paths to be reduced is determined to be the total number of flow paths of the outdoor heat exchanger minus 1. If the set change frequency is less than the minimum frequency threshold, the number of flow paths reduced is determined to be 0.

[0008] According to some embodiments of the present invention, before the step of controlling the compressor frequency to decrease the set frequency variation, the method further includes: Obtain the freezing warning temperature, current indoor temperature, target indoor temperature, current indoor humidity, and high humidity warning humidity; The set change frequency is calculated and determined based on the indoor coil temperature, the freeze warning temperature, the current indoor temperature, the target indoor temperature, the current indoor humidity, and the high humidity warning humidity.

[0009] According to some embodiments of the present invention, the formula for calculating the set change frequency is as follows: in: The set frequency of change is in Hz; This represents the current indoor coil temperature, in °C. Freezing warning temperature; The current indoor temperature is in °C. The target indoor temperature is expressed in °C. The current indoor humidity is expressed as % (%). High humidity warning; This refers to the temperature sensitivity coefficient of the coil. This is the temperature regulation coefficient; Humidity risk factor; This is the humidity correction factor, when hour, ,otherwise .

[0010] According to some embodiments of the present invention, the anti-freeze activation condition is: the indoor coil temperature is greater than 0 and less than or equal to the freeze warning temperature.

[0011] According to some embodiments of the present invention, after the step of obtaining the indoor coil temperature of the air conditioning compressor, the method further includes: If the indoor coil temperature is less than or equal to zero and remains so for at least a preset duration, the air conditioner will be controlled to perform forced defrosting or shutdown protection.

[0012] Secondly, the present invention also protects an anti-freeze control device for an air conditioner, wherein a variable flow outdoor heat exchanger is installed in the outdoor unit of the air conditioner, the device comprising: The acquisition module is used to acquire the indoor coil temperature of the air conditioner compressor in cooling mode. The first control module is used to control the air conditioner to perform anti-freeze protection based on the indoor coil temperature meeting the anti-freeze start condition; The second control module is used to control the compressor frequency to decrease under the anti-freeze protection and adjust the flow distribution mode of the outdoor heat exchanger to reduce the number of flow distribution paths.

[0013] Thirdly, the present invention also protects an air conditioner, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein a variable-flow outdoor heat exchanger is installed in the outdoor unit of the air conditioner, and the processor, when executing the computer program, implements the anti-freezing control method for the air conditioner as described in the first aspect of the present invention.

[0014] The anti-freezing control method for air conditioners according to embodiments of the present invention, while reducing frequency to prevent freezing, actively reduces the number of branch flow paths in the outdoor heat exchanger, optimizes system pressure and refrigerant phase, and improves the unit refrigerant cooling efficiency, thereby effectively compensating for cooling capacity loss. It maintains stable indoor temperature while preventing freezing, solving the core defect in related technologies where safety and comfort are difficult to balance. Furthermore, the method of the present invention has the following advantages compared to related technologies: (1) Less cooling capacity loss: By reducing the number of branch flow paths in the outdoor heat exchanger, optimizing the system condensing pressure and throttling pressure difference, the cooling efficiency per unit mass of refrigerant is improved, effectively compensating for the reduction in cooling capacity caused by compressor frequency reduction, and significantly slowing down the rise in indoor temperature. (2) Higher user comfort: There is no need to reduce the indoor fan speed or frequently start and stop the compressor, the air volume and noise level remain stable, avoiding the sudden change in body sensation caused by the sudden drop in capacity in traditional solutions. (3) Better system energy efficiency: Under anti-freezing conditions, a reasonable high-low pressure ratio and refrigerant dryness are maintained, avoiding ineffective energy consumption caused by excessive heat dissipation or flow mismatch, and improving the energy efficiency ratio when running at low load. (4) More precise control response: Based on the real-time triggering of indoor coil temperature, combined with the graded adjustable branch flow path structure, fine control matching the freezing risk level is achieved, avoiding over-protection or under-protection. (5) Strong hardware compatibility: Only a variable flow heat exchanger with electromagnetic valve control needs to be integrated in the outdoor unit. There is no need to modify the structure of the indoor unit or add complex sensors, so it is easier to promote and apply on the existing variable frequency air conditioning platform. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of the outdoor heat exchanger of the air conditioner provided by the present invention.

[0017] Figure 2 This is one of the flowcharts illustrating the anti-freezing control method for air conditioners provided by the present invention.

[0018] Figure 3 This is the second flowchart of the anti-freezing control method for air conditioners provided by the present invention.

[0019] Figure 4 This is a schematic diagram of the anti-freezing control device for air conditioners provided by the present invention.

[0020] Figure 5 This is a schematic diagram of the structure of the air conditioner provided by the present invention.

[0021] Figure label: 1. First intake solenoid valve; 2. Second intake solenoid valve; 3. Third intake solenoid valve; 4. Fourth intake solenoid valve; 5. First exhaust solenoid valve; 6. Second exhaust solenoid valve; 7. Third exhaust solenoid valve; 8. Fourth exhaust solenoid valve; 9. Main manifold solenoid valve; 10. Main intake solenoid valve; 11. Intake pipe; 12. Main outlet pipe; 20. Outdoor heat exchanger; 110. Acquisition module; 120. First control module; 130. Second control module. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0023] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0024] The anti-freeze control method, anti-freeze control device, and air conditioner proposed in this invention are described below with reference to the accompanying drawings. Before providing a detailed description of the embodiments of this invention, the overall application scenario is first described. The anti-freeze control method, anti-freeze control device, electronic device, and computer-readable storage medium of this invention can be applied locally to the air conditioner, to cloud platforms in the Internet field, or to other types of cloud platforms in the Internet field, or to third-party devices. These third-party devices may include various types such as mobile phones, tablets, laptops, in-vehicle computers, and other smart terminals.

[0025] The following description uses only the anti-freeze control method applicable to air conditioners as an example. It should be understood that the anti-freeze control method of this invention can also be applied to cloud platforms and third-party devices.

[0026] Before introducing the anti-freeze control method of the present invention, a brief description of the structure of the air conditioner on which this method is based will be given first: such as Figure 1 As shown, the outdoor unit of the air conditioner is equipped with a variable flow outdoor heat exchanger 20. The variable flow outdoor heat exchanger 20 includes multiple parallel heat exchange pipe groups. Each heat exchange pipe group has an independent inlet branch and an outlet branch, which are controlled by solenoid valves or check valves. Specifically, the heat exchanger is equipped with five inlet branches and five outlet branches, and the flow path combination control is achieved by ten solenoid valves / check valves.

[0027] like Figure 1 As shown, the first intake solenoid valve 1 (D1), the second intake solenoid valve 2 (D2), the third intake solenoid valve 3 (D3), and the fourth intake solenoid valve 4 (D4) are used to control the opening and closing of each intake branch, respectively; the first outlet solenoid valve 5 (D5), the second outlet solenoid valve 6 (D6), the third outlet solenoid valve 7 (D7), and the fourth outlet solenoid valve 8 (D8) are used to control the on / off of each outlet branch, respectively; the main manifold solenoid valve 9 (D9) is used to control whether the refrigerant after multiple heat exchanges merges into the main outlet pipe 12; and the main intake solenoid valve 10 (D10) is used to control the refrigerant to enter the main passage of the system from the main intake pipe 11.

[0028] In cooling mode, refrigerant enters through inlet pipe 11 and is controlled by different inlet solenoid valves to enter the corresponding heat exchange pipelines. After heat exchange is completed, the refrigerant is discharged to the main outlet pipe 12 through the outlet solenoid valve. In heating mode, refrigerant flows in reverse from the main outlet pipe 12, enters the heat exchange pipeline through the outlet solenoid valve, and is then guided to the main outlet pipe by the inlet solenoid valve before being output.

[0029] like Figure 1 As shown, a typical flow path control scheme in cooling mode is as follows: 1-in-1-out mode: Open the first inlet solenoid valve 1, the first outlet solenoid valve 5, and the main manifold solenoid valve 9; close the remaining solenoid valves. The refrigerant completes heat exchange only through the first heat exchange tube assembly. 1-in-2-manifold-1-out mode: Open the first inlet solenoid valve 1, the second outlet solenoid valve 6, the third outlet solenoid valve 7, and the main manifold solenoid valve 9; close the remaining solenoid valves. The refrigerant enters through the first path, exchanges heat in two separate paths, and then flows out through the combined flow. 1-in-2-manifold-1-out mode: Open the first inlet solenoid valve 1, the second outlet solenoid valve 6, the third outlet solenoid valve 7, and the main manifold solenoid valve 9; close the remaining solenoid valves. Similar to scheme 1, but different distribution ratios can be achieved by adjusting the opening degree of D6 / D7. 1-in-2-manifold-2-out mode: Open the first inlet solenoid valve 1, the second outlet solenoid valve 6, the third outlet solenoid valve 7, and the main manifold solenoid valve 9; close the remaining solenoid valves. The refrigerant exchanges heat in two separate paths and then flows out through D6 and D7 respectively, without converging. 1-in-3-combiner-1-out mode: Open the first inlet solenoid valve 1, the second outlet solenoid valve 6, the third outlet solenoid valve 7, the fourth outlet solenoid valve 8, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters through the first channel, and after heat exchange in the three channels, it flows out independently from D6, D7, and D8 respectively.

[0030] 2-inlet, 2-manifold, 1-outlet mode: Open the first inlet solenoid valve 1, the second inlet solenoid valve 2, the second outlet solenoid valve 6, the third outlet solenoid valve 7, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from the first and second lines, and after heat exchange, flows out through the combined outlet. 2-inlet, 1-manifold, 1-outlet mode: Open the first inlet solenoid valve 1, the second inlet solenoid valve 2, the first outlet solenoid valve 5, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from both lines, flows out from the first line after manifolding. 2-inlet, 1-manifold, 2-outlet mode: Open the first inlet solenoid valve 1, the second inlet solenoid valve 2, the second outlet solenoid valve 6, and the third outlet solenoid valve 7; close the remaining solenoid valves. Refrigerant enters from both lines, flows out from D6 and D7 respectively after heat exchange. 2-inlet, 3-manifold, 3-outlet mode: Open the first inlet solenoid valve 1, the second inlet solenoid valve 2, the second outlet solenoid valve 6, the third outlet solenoid valve 7, and the fourth outlet solenoid valve 8; close the remaining solenoid valves. The refrigerant enters from two streams and exits from three streams after heat exchange.

[0031] 3-inlet, 1-manifold, 1-outlet mode: Open the first intake solenoid valve 1, the second intake solenoid valve 2, the third intake solenoid valve 3, the first outlet solenoid valve 5, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters through three channels, merges, and exits through the first channel. 3-inlet, 2-manifold, 2-outlet mode: Open the first intake solenoid valve 1, the second intake solenoid valve 2, the third intake solenoid valve 3, the second outlet solenoid valve 6, and the third outlet solenoid valve 7; close the remaining solenoid valves. Refrigerant enters through three channels, exchanges heat in two channels, and then exits separately.

[0032] 4-inlet, 1-outlet mode: Open the first intake solenoid valve 1, the second intake solenoid valve 2, the third intake solenoid valve 3, the fourth intake solenoid valve 4, the first outlet solenoid valve 5, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from four channels and flows out from the first channel after converging. 5-inlet, 1-outlet mode: Open the first intake solenoid valve 1, the second intake solenoid valve 2, the third intake solenoid valve 3, the fourth intake solenoid valve 4, the fifth intake solenoid valve, the first outlet solenoid valve 5, and the main manifold solenoid valve 9; close D6-D8. Refrigerant enters from five channels and flows out from the first channel after converging. 5-inlet, 5-outlet mode: Open the first intake solenoid valve 1, the second intake solenoid valve 2, the third intake solenoid valve 3, the fourth intake solenoid valve 4, the fifth intake solenoid valve, the first outlet solenoid valve 5, the second outlet solenoid valve 6, the third outlet solenoid valve 7, the fourth outlet solenoid valve 8, and the main manifold solenoid valve 9; close none. The refrigerant enters through five channels and flows out through the five heat exchange channels.

[0033] like Figure 1 As shown, a typical flow path control scheme in heating mode is as follows: 1-in-1-out mode: Open the first outlet solenoid valve 5, the first inlet solenoid valve 1, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from the main outlet pipe 12, flows out from the first heat exchange path, and then exits from the first path. 1-in-2-manifold-1-out mode: Open the first outlet solenoid valve 5, the second outlet solenoid valve 6, the first inlet solenoid valve 1, the second inlet solenoid valve 2, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from the main outlet pipe 12, flows out from the two heat exchange paths, and then exits via the combined flow. 1-in-2-manifold-1-out mode: Open the first outlet solenoid valve 5, the third outlet solenoid valve 7, the first inlet solenoid valve 1, the second inlet solenoid valve 2, and the main manifold solenoid valve 9; close the remaining solenoid valves. Similar to scheme 1, but with a different outlet path.

[0034] 2-inlet, 1-manifold, 2-outlet mode: Open the second outlet solenoid valve 6, the third outlet solenoid valve 7, the second inlet solenoid valve 2, the third inlet solenoid valve 3, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from two lines, and after heat exchange, flows out from D6 and D7 respectively. 2-inlet, 2-manifold, 1-outlet mode: Open the second outlet solenoid valve 6, the third outlet solenoid valve 7, the second inlet solenoid valve 2, the third inlet solenoid valve 3, and the main manifold solenoid valve 9; close the remaining solenoid valves. Refrigerant enters from two lines, and after heat exchange, flows out through the combined flow. 2-inlet, 1-manifold, 1-outlet mode: Open the first outlet solenoid valve 5, the second inlet solenoid valve 2, and the third inlet solenoid valve 3; close the remaining solenoid valves. Refrigerant enters from two lines, and after converging, flows out from the first line.

[0035] 3-inlet, 1-merge, 1-outlet mode: Open the first outlet solenoid valve 5, the second inlet solenoid valve 2, the third inlet solenoid valve 3, and the fourth inlet solenoid valve 4; close the remaining solenoid valves. Refrigerant enters through three channels, merges, and exits through the first channel. 3-inlet, 2-merge, 2-outlet mode: Open the second outlet solenoid valve 6, the third outlet solenoid valve 7, the second inlet solenoid valve 2, the third inlet solenoid valve 3, and the fourth inlet solenoid valve 4; close the remaining solenoid valves. Refrigerant enters through three channels, exchanges heat, and exits through D6 and D7 respectively.

[0036] 4-in-1-combiner-1-out mode: Open the first outlet solenoid valve 5, the second inlet solenoid valve 2, the third inlet solenoid valve 3, the fourth inlet solenoid valve 4, and the fifth inlet solenoid valve; close the remaining solenoid valves. Refrigerant enters from four channels, converges, and flows out from the first channel. 5-in-5-out mode: Open the first outlet solenoid valve 5, the second outlet solenoid valve 6, the third outlet solenoid valve 7, the fourth outlet solenoid valve 8, the second inlet solenoid valve 2, the third inlet solenoid valve 3, the fourth inlet solenoid valve 4, and the fifth inlet solenoid valve; close D1 and D9. Refrigerant enters from five channels, exchanges heat in each channel, and then flows out separately.

[0037] The anti-freezing control method of the present invention is described below with reference to the accompanying drawings.

[0038] like Figure 2 and Figure 3 As shown, the anti-freezing control method for an air conditioner according to a first aspect embodiment of the present invention includes: Step S1: In cooling mode, obtain the indoor coil temperature of the air conditioner compressor.

[0039] It is understandable that the indoor coil temperature refers to the temperature of the copper tube surface of the evaporator in the indoor unit of the air conditioner or the area through which the refrigerant flows. It is usually collected in real time by a temperature sensor set in the middle of the evaporator or near the return pipe, which can reflect the risk of evaporator icing.

[0040] In step S1, after the air conditioning system enters the cooling operation state, the controller periodically reads the signal from the temperature sensor to obtain the current indoor coil temperature value. In this way, obtaining the above parameters can provide a direct basis for subsequent judgment on whether freeze protection is triggered, and the indoor coil temperature value can sensitively reflect the evaporator heat exchange status and potential frosting trend.

[0041] Step S2: Based on the indoor coil temperature meeting the anti-freeze start-up conditions, control the air conditioner to perform anti-freeze protection.

[0042] In step S2, the anti-freeze activation condition refers to the preset temperature threshold criterion. For example, if the indoor coil temperature is lower than the freezing warning temperature (e.g., 3°C) but higher than 0°C, it indicates that the evaporator is at risk of frosting but has not yet completely frozen.

[0043] Specifically, the controller compares the acquired indoor coil temperature with a preset threshold; if the activation conditions are met, the anti-freeze protection logic is activated, and the protection execution phase begins. This prevents frost or even ice buildup on the evaporator surface due to excessively low coil temperature, thus preventing malfunctions such as duct blockage, reduced heat exchange efficiency, and compressor liquid slugging.

[0044] Step S3: Under anti-freeze protection, control the compressor frequency to decrease and adjust the flow splitting mode of the outdoor heat exchanger 20 to reduce the number of flow splitting paths.

[0045] It should be explained that the flow splitting mode of the outdoor heat exchanger 20 refers to the way the refrigerant flows through the outdoor heat exchanger 20 by controlling the flow path of the refrigerant through the solenoid valve group; the number of flow splitting paths refers to the number of parallel flow paths that participate in heat exchange at the same time, such as 5 paths, 3 paths or 1 path.

[0046] In step S3, after entering anti-freeze protection mode, the system simultaneously performs two key operations: first, it controls the inverter compressor to reduce its operating frequency to decrease the refrigerant circulation flow, thereby inhibiting further cooling of the evaporator; second, it adjusts the flow distribution mode of the variable flow outdoor heat exchanger 20 installed in the outdoor unit to actively reduce the number of refrigerant flow paths involved in heat exchange. Thus, these two actions work synergistically: the former reduces the risk of freezing at the source, while the latter partially compensates for the cooling capacity loss caused by frequency reduction by optimizing the system's circulation characteristics, thereby achieving a balance between safety and comfort.

[0047] In related technologies, when traditional air conditioners operate in cooling mode in low-temperature and high-humidity environments, they typically only take passive measures such as reducing the compressor frequency or shutting down if the indoor coil temperature is detected to be too low. While this method can prevent freezing, it significantly weakens the cooling capacity, causing the indoor temperature to rise again, worsening the user's comfort, and even triggering frequent start-stop cycles, affecting system stability.

[0048] To address the shortcomings of the aforementioned related technologies, this invention proposes an anti-freezing control method based on system-level coordinated regulation. Under the premise of reducing the frequency to prevent coil freezing, the pressure and flow matching relationship of the refrigeration cycle is reconstructed by adjusting the outdoor flow state of the outdoor heat exchanger 20, thereby maintaining a high unit refrigerant refrigeration efficiency at a lower frequency.

[0049] Specifically, when the compressor frequency decreases, the total refrigerant flow rate decreases. If the outdoor heat exchanger 20 continues to operate in its entire flow path, it will lead to excessive condensation, low system pressure, insufficient refrigerant dryness after throttling, reduced latent heat of vaporization utilization, and further reduction in cooling capacity. To address this, the present invention integrates a heat exchanger with variable flow splitting function into the outdoor unit and actively reduces the number of effective flow splitting paths during anti-freeze protection. This moderately limits the heat exchange area on the outdoor side, maintaining a higher condensing pressure while simultaneously increasing the refrigerant flow rate and heat exchange intensity in the remaining flow path. With the expansion valve opening remaining essentially unchanged, the higher condensing pressure combined with a reasonable subcooling results in better evaporation characteristics for the two-phase refrigerant after throttling, enhancing the cooling capacity per unit mass of refrigerant. Therefore, despite the decrease in compressor frequency, the overall reduction in cooling capacity is effectively suppressed.

[0050] In summary, this method achieves a dual objective. On the one hand, by reducing the compressor frequency, it effectively suppresses the downward trend of coil temperature and resolves the risk of freezing. On the other hand, by reducing the number of 20-way flow paths in the outdoor heat exchanger, it optimizes the system condensing pressure and refrigerant phase, improves the unit refrigerant refrigeration efficiency, and compensates for the loss of cooling capacity caused by frequency reduction. Ultimately, it resolves the technical contradiction in related technologies of "sacrificing comfort for safety and taking risks for comfort".

[0051] Furthermore, based on the above working principle, the specific working process of the anti-freezing control method of the present invention is illustrated as follows: When the air conditioning system is running continuously in cooling mode, the controller monitors the indoor coil temperature in real time. When the environment is in a low temperature and high humidity condition, and the coil temperature gradually drops below the preset freezing warning threshold (e.g., 3°C) but has not yet reached 0°C, the system determines that it has entered the freezing risk zone and then initiates the anti-freezing protection process.

[0052] At this point, the controller first calculates the required reduction in compressor frequency and sends a command to the inverter drive module to gradually lower the compressor's operating frequency. Simultaneously, according to a preset strategy (such as switching the outdoor heat exchanger 20 from 5 channels to 2 channels by default), the controller sends a control signal to the solenoid valve group located inside the outdoor unit, closing some of the intake or exhaust solenoid valves to reduce the number of refrigerant flow paths involved in heat exchange.

[0053] With the reduction in the number of branch flow paths, the effective heat exchange area of ​​the outdoor heat exchanger 20 is correspondingly reduced, the condensation process is moderately suppressed, and the high-pressure side pressure of the system is maintained at a high level. This results in a higher latent heat of vaporization utilization rate of the refrigerant after throttling by the electronic expansion valve, thereby improving the refrigeration efficiency per unit of refrigerant. Therefore, although the reduction in compressor frequency leads to a decrease in total refrigerant flow, the overall reduction in cooling capacity can be significantly mitigated.

[0054] In this state, the heat load of the indoor evaporator is reasonably controlled, and the coil temperature no longer continues to drop. Instead, due to the optimized system circulation, it tends to stabilize or slightly rise, successfully avoiding the freezing point. Simultaneously, because the cooling capacity does not drop significantly, the indoor temperature fluctuations are minimal, and users perceive almost no difference. Thus, the entire process requires no shutdown or significant adjustments to the fan speed, ensuring both equipment safety and maintaining a good user experience.

[0055] In summary, the anti-freezing control method for air conditioners according to embodiments of the present invention, while reducing frequency to prevent freezing, actively reduces the number of branch flow paths in the outdoor heat exchanger 20, optimizes system pressure and refrigerant phase, and improves the unit refrigerant cooling efficiency, thereby effectively compensating for cooling capacity loss. It maintains stable indoor temperature while preventing freezing, solving the core defect in related technologies where safety and comfort are difficult to balance. Furthermore, the method of the present invention has the following advantages compared to related technologies: (1) Less cooling capacity loss: By reducing the number of branch flow paths in the outdoor heat exchanger 20, the system condensing pressure and throttling pressure difference are optimized, improving the cooling efficiency per unit mass of refrigerant, effectively compensating for the cooling capacity reduction caused by compressor frequency reduction, and significantly slowing down the rise in indoor temperature. (2) Higher user comfort: There is no need to reduce the indoor fan speed or frequently start and stop the compressor, the air volume and noise level remain stable, avoiding the sudden change in body sensation caused by the sudden drop in capacity in traditional solutions. (3) Better system energy efficiency: Under anti-freezing conditions, a reasonable high and low pressure ratio and refrigerant dryness are maintained, avoiding ineffective energy consumption caused by excessive heat dissipation or flow mismatch, and improving the energy efficiency ratio when running at low load. (4) More precise control response: Based on the real-time triggering of indoor coil temperature, combined with the graded adjustable branch flow path structure, fine control matching the freezing risk level is achieved, avoiding over-protection or under-protection. (5) Strong hardware compatibility: Only a variable flow heat exchanger with electromagnetic valve control needs to be integrated in the outdoor unit. There is no need to modify the structure of the indoor unit or add complex sensors, so it is easier to promote and apply on the existing variable frequency air conditioning platform.

[0056] like Figure 2 and Figure 3 As shown, according to some embodiments of the present invention, under antifreeze protection, the steps of controlling the compressor frequency to decrease and adjusting the flow distribution mode of the outdoor heat exchanger 20 to reduce the number of flow distribution paths specifically include: Control the compressor frequency to decrease the set frequency; Based on the set change frequency, determine the number of flow path reductions in the flow path of the outdoor heat exchanger 20, and adjust the flow path reduction mode of the outdoor heat exchanger 20 according to the number of flow path reductions.

[0057] It should be noted that this embodiment further clarifies the linkage logic between compressor frequency reduction and outdoor heat exchanger 20 diversion adjustment in antifreeze protection. That is, the system does not execute the two operations independently, but uses the set change frequency as an intermediate decision variable to coordinate frequency adjustment and flow path reconstruction.

[0058] Specifically, once the anti-freezing conditions are met, the controller first calculates the amount of compressor frequency reduction (i.e., the set frequency change) required to suppress the coil temperature drop. This value not only guides compressor frequency adjustment but also serves as a basis for judgment, thus mapping the number of 20 flow paths in the outdoor heat exchanger that should be reduced. For example, if the calculation shows a 10Hz frequency reduction is needed, indicating a higher risk of freezing, then a larger number of flow paths will be reduced (e.g., from 5 to 2); if only a 3Hz frequency reduction is needed, then only 1 flow path may be reduced or the current flow path may be maintained. This mapping relationship can be based on experimental calibration or preset rules to ensure that the flow path adjustment range matches the frequency reduction intensity.

[0059] For example, under a certain low temperature and high humidity condition, the system calculates that the set frequency of change is 8Hz. According to the preset strategy, 8Hz corresponds to a reduction of 2 flow paths, so the controller switches the outdoor heat exchanger 20 from a 5-path operation mode to a 3-path mode, and at the same time reduces the compressor frequency by 8Hz.

[0060] In this way, by using a set frequency change as a link to achieve the synergy of frequency reduction and flow regulation, it can accurately respond to the freezing risk level and dynamically compensate for the loss of cooling capacity. While ensuring anti-freezing safety, it can more effectively maintain indoor temperature stability and system operating efficiency.

[0061] In some specific embodiments of the present invention, the step of determining the number of flow paths to be reduced in the branch flow path of the outdoor heat exchanger 20 according to a set change frequency specifically includes: When the set change frequency is less than the maximum frequency threshold and greater than or equal to the first change frequency, the number of flow paths to be reduced is determined as the first reduction number; When the set change frequency is less than the first change frequency and greater than or equal to the second change frequency, the number of flow paths to be reduced is determined to be the second reduction number; If the set change frequency is less than the second change frequency and greater than or equal to the minimum frequency threshold, the number of flow path reductions is determined as the third reduction number.

[0062] Among them, the first reduction is less than the total number of flow paths of the outdoor heat exchanger 20, the second reduction is less than the first reduction, and the third reduction is less than the second reduction and greater than or equal to 1.

[0063] This embodiment sets multiple frequency threshold ranges, discretizes the continuously changing frequency into several levels, and matches each level with a corresponding flow path to reduce the number of flow paths, thereby achieving hierarchical and orderly flow regulation.

[0064] Specifically, the system presets a maximum frequency threshold (e.g., 12 Hz), a first frequency variation (e.g., 8 Hz), a second frequency variation (e.g., 4 Hz), and a minimum frequency threshold (e.g., 2 Hz), forming three effective control intervals. When the calculated set frequency variation falls within a certain interval, a specific flow path reduction strategy is activated.

[0065] If the frequency reduction is large (e.g., 8 Hz ≤ Δf < 12 Hz), it indicates a high risk of freezing. In this case, reduce more flow paths (first, reduce the number of paths, such as reducing 3 paths) to more effectively compensate for the loss of power and increase system pressure. If the frequency reduction is moderate (e.g., 4 Hz ≤ Δf < 8 Hz), reduce fewer flow paths (second, reduce the number of paths, such as reducing 2 paths). If the frequency reduction is small (e.g., 2 Hz ≤ Δf < 4 Hz), only fine-tune the flow paths (third, reduce the number of paths, such as reducing 1 path) to avoid excessive intervention.

[0066] Each reduction quantity is less than the total number of flow paths of the outdoor heat exchanger 20 (e.g., a total of 5 flow paths), and satisfies the following condition: First reduction quantity > Second reduction quantity > Third reduction quantity ≥ 1, ensuring that the adjustment action is both effective and not excessive.

[0067] For example, assuming that the outdoor heat exchanger 20 has 5 channels and the set change frequency is 6 Hz, which falls in the second interval (≥4 Hz and <8 Hz), then the number of flow paths is reduced by 2, and the system will switch the flow splitting mode from 5 channels to 3 channels.

[0068] In this way, the above-mentioned hierarchical mapping mechanism enables precise matching between flow path adjustment and freezing risk level. While preventing coil freezing, it can avoid pressure fluctuations or energy efficiency losses caused by sudden changes in flow path, thereby achieving stable, efficient, and adaptive anti-freezing control.

[0069] In some other embodiments of the present invention, the step of determining the number of flow paths to be reduced in the branch flow path of the outdoor heat exchanger 20 according to a set change frequency specifically includes: When the set change frequency is greater than or equal to the maximum frequency threshold, the number of flow paths to be reduced is determined to be the total number of flow paths of the outdoor heat exchanger 20 minus 1. When the set change frequency is less than the minimum frequency threshold, the number of flow paths reduced is determined to be 0.

[0070] In this embodiment, when the set frequency variation reaches or exceeds the preset maximum frequency threshold (e.g., 12 Hz), it indicates that the indoor coil temperature is severely low, and the risk of freezing is extremely high. At this time, the system reduces the number of flow paths by one less than the total number of flow paths in the outdoor heat exchanger 20, meaning only a single flow path is maintained in operation. This operation maximizes the refrigerant flow rate and heat transfer intensity in the remaining flow paths, significantly increases the condensing pressure, thereby rapidly improving the evaporator-side operating conditions and strongly suppressing the freezing trend.

[0071] Conversely, when the set frequency of change is lower than the minimum frequency threshold (e.g., 2 Hz), it indicates that the risk of freezing is extremely low, requiring only minor intervention. In this case, the system determines that there is no need to adjust the structure of the outdoor heat exchanger 20, sets the number of flow path reductions to 0, that is, maintains the current flow splitting mode unchanged, avoids unnecessary solenoid valve operation, reduces energy consumption and component wear, and maintains system operational stability.

[0072] For example, if the outdoor heat exchanger 20 has a total of 5 flow paths, and the calculated set change frequency is 13 Hz (that is, ≥ the maximum threshold of 12 Hz), then 4 flow paths will be reduced, leaving only 1 flow path in operation; if the set change frequency is 1.5 Hz (that is, < the minimum threshold of 2 Hz), then no flow paths will be reduced, and the flow splitting mode will remain unchanged.

[0073] In summary, by employing a boundary processing mechanism that covers both high and low ends, this solution ensures maximum protection under high freezing risk and avoids over-regulation under low risk, thereby improving the accuracy, response precision, and long-term reliability of the entire anti-freeze control system.

[0074] like Figure 2 and Figure 3 As shown, according to some embodiments of the present invention, before the step of controlling the compressor frequency to decrease the set change frequency, the anti-freeze control method further includes: Obtain the freezing warning temperature, current indoor temperature, target indoor temperature, current indoor humidity, and high humidity warning humidity; The set change frequency is calculated and determined based on the indoor coil temperature, freeze warning temperature, current indoor temperature, target indoor temperature, current indoor humidity, and high humidity warning humidity.

[0075] Specifically, before implementing compressor frequency reduction, the system first collects six key parameters: indoor coil temperature, freeze warning temperature, current indoor temperature and target indoor temperature, current indoor humidity, and high humidity warning humidity. The indoor coil temperature reflects the current risk of icing, the freeze warning temperature defines the safety threshold, the current indoor temperature and target indoor temperature characterize temperature control deviation, and the current indoor humidity and high humidity warning humidity assess the risk of increased frosting. These parameters together constitute a decision input set that integrates thermodynamic state and user comfort needs.

[0076] Based on this, the controller comprehensively judges the actual freezing risk level through a preset algorithm. For example, when the coil temperature is close to the freezing warning value, the indoor humidity is much higher than the high humidity warning value, and the room temperature is lower than the set value, it indicates that the system is in a triple unfavorable condition of "low temperature + high humidity + overcooling", requiring a significant frequency reduction; conversely, if only the coil temperature is slightly low but the room temperature is high and the humidity is normal, a small adjustment can be made. It can be understood that the above multi-parameter coupled calculation avoids the false triggering or insufficient response caused by traditional single threshold triggering.

[0077] In this way, by introducing parameters such as temperature, humidity and set temperature, the present invention makes the determination of the set change frequency more accurate and reasonable. This not only effectively avoids the risk of freezing, but also dynamically balances the cooling capacity and protection strength according to the actual environment, thereby significantly improving the intelligence, comfort and energy efficiency of antifreeze control.

[0078] Furthermore, the formula for calculating the frequency of change is set as follows: In the above calculation formula, To set the frequency of variation, the unit is Hz.

[0079] As the core anti-freezing item, this section reflects the degree to which the indoor coil temperature falls below the freezing warning threshold. The current indoor coil temperature is in °C and is collected in real time by a temperature sensor installed on the indoor evaporator. This is the preset freezing warning temperature, typically ranging from 2°C to 3°C, representing the critical temperature at which the coil begins to have a risk of frost formation. Ensure only when When the output of this item is positive, it triggers frequency reduction; if If the value is zero, then the anti-freeze frequency reduction will not be implemented. The coil temperature sensitivity coefficient ranges from 5Hz / ℃ to 8Hz / ℃, representing the frequency reduction that occurs when the coil temperature drops by 1℃ below the freezing warning temperature.

[0080] This is the temperature deviation correction item. This part is used to dynamically adjust the frequency reduction intensity based on the deviation between the current room temperature and the user-set temperature, so as to balance anti-freezing and cooling comfort. The current indoor temperature is in °C. The target indoor temperature is expressed in °C; when (Room temperature is too high), this item is negative, making Reduce, that is, appropriately suppress the frequency reduction amplitude, and prioritize maintaining cooling capacity; when (The room temperature is low), this item is positive, making Increase and strengthen frequency reduction to avoid excessive cooling and the risk of icing; This is a humidity correction factor, used to enhance the effect of this correction term in high humidity environments. Wherein, when... hour, ,otherwise . This is the temperature regulation coefficient, with a value ranging from 2Hz / ℃ to 4Hz / ℃.

[0081] This is a high humidity risk factor addition. This part is used to add an extra frequency reduction amount under high humidity conditions to cope with the accelerated frosting effect caused by increased humidity. The current indoor humidity is expressed as % (%). High humidity warning; Ensure that additional frequency reduction is only introduced when humidity exceeds a critical value; The humidity risk factor ranges from 0.3Hz / % to 0.5Hz / %, representing the additional frequency reduction that occurs for every 1% increase in relative humidity beyond the critical value.

[0082] Furthermore, to ensure the safe and stable operation of the system, the calculated frequency reduction amount must meet the following restrictions: (1) The actual compressor operating frequency after frequency reduction must not be lower than its minimum allowable operating frequency (e.g., 30 Hz); (2) If the indoor coil temperature is detected to be less than or equal to 0 and the duration exceeds the preset threshold, it is determined that freezing has occurred. At this time, the above formula is no longer relied upon, but the compressor frequency is forcibly reduced to the minimum, and the emergency processing logic is activated, such as briefly switching to the heating mode for 10–20 seconds to perform local defrosting.

[0083] In summary, this calculation model achieves a dynamic balance between anti-freeze protection and indoor temperature control targets by integrating three factors: coil temperature, room temperature deviation, and ambient humidity. In practical applications, the coefficient... Calibration and optimization can be performed based on the evaporator area, fan performance, and regional climate characteristics of the specific model to achieve the best control effect.

[0084] According to some embodiments of the present invention, the anti-freeze activation condition is: the indoor coil temperature is greater than 0 and less than or equal to the freeze warning temperature.

[0085] It should be explained that when the indoor coil temperature is above 0°C, it indicates that the evaporator has not yet frozen substantially. However, if it has dropped to the freezing warning temperature (usually 2°C to 3°C) or below, the surface condensate is very likely to frost rapidly in the low temperature and high humidity environment, and then develop into an ice layer. At this time, the system is in a "critical freezing" state, and intervention is urgently needed to prevent it from deteriorating.

[0086] Therefore, this embodiment limits the activation conditions to the range of temperatures greater than 0°C and less than or equal to the freezing warning temperature, which can effectively prevent the protection from being triggered only after the coil has frozen, thereby achieving proactive and preventative control; at the same time, it eliminates false triggering when the coil temperature is normal, thereby ensuring that the anti-freeze logic is activated only when a real risk exists.

[0087] like Figure 2 and Figure 3 As shown, according to some embodiments of the present invention, after the step of obtaining the indoor coil temperature of the air conditioning compressor, the anti-freeze control method further includes: If the indoor coil temperature is less than or equal to zero and remains so for at least a preset duration, the air conditioner will be controlled to perform forced defrosting or shutdown protection.

[0088] In this embodiment, it can be understood that after obtaining the indoor coil temperature of the air conditioner, the system further determines whether the temperature is less than or equal to 0°C and remains at or above a preset duration (e.g., 5 to 10 seconds). If this condition is met, it is determined that the indoor evaporator has undergone substantial freezing. At this point, the anti-freeze protection mechanism is no longer applicable, and a higher level of emergency response measures need to be initiated.

[0089] Specifically, the controller will control the air conditioner to perform forced defrosting or shutdown protection. Forced defrosting refers to briefly switching the system's operating state in cooling mode, such as instantly switching to heating mode via a four-way valve or activating the auxiliary electric heating device, so that the high-temperature refrigerant flows through the indoor evaporator to melt the ice layer; shutdown protection directly stops the compressor and fan to prevent the ice layer from aggravating the serious malfunctions such as air duct blockage, heat exchange failure, or compressor liquid slugging caused by the ice layer.

[0090] In summary, this step serves as a fallback safety mechanism for anti-freezing control, complementing the aforementioned preventative protection based on coil temperatures above 0°C. On one hand, the former is used to proactively intervene in critical risks; on the other hand, the latter is used to address existing freezing failures. Together, they constitute a complete indoor freezing protection system, thereby significantly improving the operational reliability and safety of the air conditioning system under low temperature and high humidity conditions.

[0091] In one specific embodiment of the present invention, when the indoor coil temperature is detected to be less than or equal to 0°C and the duration of this state reaches a preset duration (e.g., 30 seconds), the system determines that the indoor evaporator has frozen and then initiates the emergency defrosting process.

[0092] The specific execution steps are as follows: First, fully open the electronic expansion valve to increase the refrigerant flow and increase the refrigerant pressure and temperature entering the evaporator; at the same time, increase the indoor fan speed by two levels to enhance air turbulence and promote heat exchange and moisture evaporation on the ice surface; on this basis, activate the hot flow defrosting mode, that is, without switching the four-way valve, by increasing the compressor frequency and coordinating with the 20-way flow path adjustment of the outdoor heat exchanger, the system generates a relatively high temperature low-pressure refrigerant return flow in the refrigeration cycle, using its sensible heat to gently heat the frozen evaporator.

[0093] The system continues to perform the above defrosting operation and continuously monitors the indoor coil temperature change within 3 minutes. If the coil temperature rises above 0°C and the trend stabilizes, the defrosting is considered successful, and normal cooling operation is automatically restored; if the coil temperature does not show significant improvement within 3 minutes, the system is considered severely frozen and cannot be effectively thawed by heat flow. In this case, the compressor and fan are immediately shut down, and the system enters a shutdown protection state.

[0094] After a 3-minute shutdown, the system attempts to restart and checks the coil temperature again. If the temperature has returned to normal, cooling operation continues; if it remains frozen, the defrosting process can be repeated or the system can enter long-term protection mode to prevent equipment damage.

[0095] Thus, this embodiment, through a combination of fully opening the electronic expansion valve, increasing the fan speed, and using heat flow for defrosting, can effectively intervene in mild to moderate freezing without interrupting the cooling mode. It balances safety, energy efficiency, and user experience, and is significantly better than the traditional approach of directly shutting down the machine or forcibly switching to heating for defrosting.

[0096] The anti-freeze control device for air conditioners provided by the present invention will be described below. The anti-freeze control device for air conditioners described below can be referred to in correspondence with the anti-freeze control method for air conditioners described above.

[0097] like Figure 4 As shown, an anti-freeze control device for an air conditioner according to a second aspect embodiment of the present invention includes: The acquisition module 110 is used to acquire the indoor coil temperature of the air conditioner compressor in cooling mode. The first control module 120 is used to control the air conditioner to perform anti-freeze protection based on the indoor coil temperature meeting the anti-freeze start-up conditions. The second control module 130 is used to control the compressor frequency to decrease under anti-freeze protection and adjust the flow distribution mode of the outdoor heat exchanger 20 to reduce the number of flow distribution paths.

[0098] Figure 5 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 5As shown, the electronic device may include a processor 810, a communication interface 820, a memory 830, and a communication bus 840. The processor 810, communication interface 820, and memory 830 communicate with each other via the communication bus 840. The processor 810 can call logic instructions in the memory 830 to execute an anti-freeze control method for the air conditioner, including: in cooling mode, acquiring the indoor coil temperature of the air conditioner compressor; based on the indoor coil temperature meeting the anti-freeze start-up conditions, controlling the air conditioner to perform anti-freeze protection; under anti-freeze protection, controlling the compressor frequency to decrease and adjusting the flow distribution mode of the outdoor heat exchanger 20 to reduce the number of flow distribution paths.

[0099] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0100] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by the computer, the computer can execute the anti-freeze control method for the air conditioner provided by the above methods, including: in cooling mode, obtaining the indoor coil temperature of the air conditioner compressor; based on the indoor coil temperature meeting the anti-freeze start condition, controlling the air conditioner to perform anti-freeze protection; under anti-freeze protection, controlling the compressor frequency to decrease and adjusting the flow distribution mode of the outdoor heat exchanger 20 to reduce the number of flow distribution paths.

[0101] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described anti-freeze control methods for air conditioners, including: in cooling mode, acquiring the indoor coil temperature of the air conditioner compressor; based on the indoor coil temperature meeting the anti-freeze start-up conditions, controlling the air conditioner to perform anti-freeze protection; under anti-freeze protection, controlling the compressor frequency to decrease and adjusting the flow distribution mode of the outdoor heat exchanger 20 to reduce the number of flow distribution paths.

[0102] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0103] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preventing freezing in an air conditioner, characterized in that, The outdoor unit of the air conditioner is equipped with a variable flow outdoor heat exchanger, and the method includes: In cooling mode, the indoor coil temperature of the air conditioner compressor is obtained; Based on the indoor coil temperature meeting the anti-freeze start-up conditions, the air conditioner is controlled to perform anti-freeze protection. Under the anti-freeze protection, the frequency of the compressor is reduced, and the flow distribution mode of the outdoor heat exchanger is adjusted to reduce the number of flow distribution paths.

2. The anti-freezing control method for air conditioners according to claim 1, characterized in that, Under the anti-freeze protection, the steps of reducing the frequency of the compressor and adjusting the flow distribution mode of the outdoor heat exchanger to reduce the number of flow distribution paths specifically include: The frequency of the compressor is controlled to decrease from the set frequency variation. Based on the set change frequency, the number of flow paths to be reduced in the outdoor heat exchanger is determined, and the flow distribution mode of the outdoor heat exchanger is adjusted according to the number of flow paths to be reduced.

3. The anti-freezing control method for air conditioners according to claim 2, characterized in that, The step of determining the number of flow paths to be reduced in the outdoor heat exchanger based on the set change frequency specifically includes: When the set change frequency is less than the maximum frequency threshold and greater than or equal to the first change frequency, the number of flow paths reduced is determined to be the first reduction number; When the set change frequency is less than the first change frequency and greater than or equal to the second change frequency, the flow path reduction amount is determined to be the second reduction amount; If the set change frequency is less than the second change frequency and greater than or equal to the minimum frequency threshold, the number of flow paths reduced is determined to be the third reduction number; Among them, the first reduction is less than the total number of flow paths of the outdoor heat exchanger, the second reduction is less than the first reduction, and the third reduction is less than the second reduction but greater than or equal to 1.

4. The anti-freezing control method for air conditioners according to claim 2, characterized in that, The step of determining the number of flow paths to be reduced in the outdoor heat exchanger based on the set change frequency specifically includes: When the set change frequency is greater than or equal to the maximum frequency threshold, the number of flow paths to be reduced is determined to be the total number of flow paths of the outdoor heat exchanger minus 1. If the set change frequency is less than the minimum frequency threshold, the number of flow paths reduced is determined to be 0.

5. The anti-freezing control method for an air conditioner according to any one of claims 2 to 4, characterized in that, Before the step of controlling the compressor frequency to decrease the set frequency, the method further includes: Obtain the freezing warning temperature, current indoor temperature, target indoor temperature, current indoor humidity, and high humidity warning humidity; The set change frequency is calculated and determined based on the indoor coil temperature, the freeze warning temperature, the current indoor temperature, the target indoor temperature, the current indoor humidity, and the high humidity warning humidity.

6. The anti-freezing control method for air conditioners according to claim 5, characterized in that, The formula for calculating the set frequency of change is: in: The set frequency of change is in Hz; This represents the current indoor coil temperature, in °C. Freezing warning temperature; The current indoor temperature is in °C. The target indoor temperature is expressed in °C. The current indoor humidity is expressed as % (%). High humidity warning; This refers to the temperature sensitivity coefficient of the coil. This is the temperature regulation coefficient; Humidity risk factor; This is the humidity correction factor, when hour, ,otherwise .

7. The anti-freezing control method for an air conditioner according to any one of claims 1 to 4, characterized in that, The anti-freeze activation condition is: the indoor coil temperature is greater than 0 and less than or equal to the freeze warning temperature.

8. The anti-freezing control method for air conditioners according to claim 7, characterized in that, After the step of obtaining the indoor coil temperature of the air conditioner compressor, the method further includes: If the indoor coil temperature is less than or equal to zero and remains so for at least a preset duration, the air conditioner will be controlled to perform forced defrosting or shutdown protection.

9. An anti-freeze control device for an air conditioner, characterized in that, The outdoor unit of the air conditioner is equipped with a variable flow outdoor heat exchanger, and the device includes: The acquisition module is used to acquire the indoor coil temperature of the air conditioner compressor in cooling mode. The first control module is used to control the air conditioner to perform anti-freeze protection based on the indoor coil temperature meeting the anti-freeze start condition; The second control module is used to control the compressor frequency to decrease under the anti-freeze protection and adjust the flow distribution mode of the outdoor heat exchanger to reduce the number of flow distribution paths.

10. An air conditioner, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The outdoor unit of the air conditioner is equipped with a variable flow outdoor heat exchanger, and the processor executes the computer program to implement the anti-freezing control method of the air conditioner as described in any one of claims 1 to 8.

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