Air conditioner, control method and device thereof, storage medium and computer program product

Abstract

The application provides an air conditioner and a control method, device, storage medium and computer program product thereof. The method comprises: when the air conditioner is operated in a cooling mode under the condition that an outdoor ambient temperature is lower than a preset temperature value, collecting operation parameters and environmental parameters of the air conditioner; judging whether the collected operation parameters and / or environmental parameters meet a preset frosting risk condition; and if it is judged that the operation parameters and / or environmental parameters meet the preset frosting risk condition, adjusting the rotation speed of an outdoor fan of the air conditioner to perform anti-frosting control on the air conditioner. The scheme provided by the application can effectively prevent the indoor heat exchanger from frosting.

Description

Technical Field

[0001] This invention relates to the field of control, and more particularly to an air conditioner and its control method, apparatus, storage medium and computer program product. Background Technology

[0002] During the cooling operation of an air conditioner, when the ambient temperature is low (such as at night in spring and autumn or during transitional seasons), if cooling is still required indoors, a "low-temperature cooling" condition is likely to occur. At this time, due to the low temperature of the outdoor cold source, the condenser's heat dissipation capacity is too strong, while the indoor heat load is small, resulting in insufficient heat absorption capacity of the evaporator. This leads to a mismatch between the system's heat load and heat exchange capacity, causing an imbalance in the system's refrigerant circulation pressure ratio. The evaporator surface temperature can easily drop below 0°C. When the indoor air humidity is high, water vapor condenses and frosts on the fins of the indoor heat exchanger (evaporator), causing risks such as increased air resistance, decreased heat exchange efficiency, and compressor liquid return. Summary of the Invention

[0003] The main objective of this invention is to overcome the deficiencies of the aforementioned related technologies and provide an air conditioner and its control method, device, storage medium, and computer program product to solve the problem of indoor heat exchanger frosting under low-temperature refrigeration conditions in the related technologies.

[0004] The present invention provides a method for controlling an air conditioner, comprising: when the outdoor ambient temperature is lower than a preset temperature value, when the air conditioner is turned on for cooling, collecting the operating parameters and environmental parameters of the air conditioner; determining whether the collected operating parameters and / or environmental parameters meet preset frosting risk conditions; if the operating parameters and / or environmental parameters meet the preset frosting risk conditions, adjusting the speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner.

[0005] Optionally, the operating parameters include at least one of: indoor heat exchanger temperature, return gas pressure, indoor fan speed, outdoor fan speed, and compressor operating frequency; the environmental parameters include at least one of: outdoor ambient temperature, indoor ambient temperature, and indoor ambient humidity; the preset frosting risk conditions include at least one of: the indoor heat exchanger temperature is less than a first preset temperature threshold and continues to decrease within a first preset time period; the return gas pressure is less than a set pressure, wherein the set pressure is the minimum safe return gas pressure set at the current compressor operating frequency; the indoor ambient humidity is greater than a preset humidity threshold and the indoor heat exchanger temperature is less than a second preset temperature threshold.

[0006] Optionally, adjusting the outdoor fan speed of the air conditioner to control frost formation includes: reducing the outdoor fan speed of the air conditioner to a target speed value; wherein the target speed value is determined based on the indoor heat exchanger temperature.

[0007] Optionally, determining the target rotational speed based on the indoor heat exchanger temperature includes: calculating the target rotational speed based on the set outdoor fan speed, the set minimum indoor heat exchanger temperature, and the indoor heat exchanger temperature using the following formula:

[0008]

[0009] in, This refers to the external fan speed. Set the speed of the external fan. The indoor heat exchanger temperature. k is the adjustment coefficient used to set the minimum surface temperature of the indoor heat exchanger.

[0010] Optionally, the adjustment coefficient is determined based on a preset correspondence between the air conditioner's cooling capacity and / or horsepower and the adjustment coefficient.

[0011] Optionally, it also includes: if the speed of the outdoor fan has dropped to a preset minimum allowable speed and the temperature of the indoor heat exchanger is less than a first preset temperature threshold, then the operating frequency of the compressor is reduced to a preset frequency and the speed of the indoor fan is increased to a preset speed.

[0012] Optionally, it further includes: after performing anti-frost control on the air conditioner, when the operating parameters and / or the environmental parameters meet the conditions for exiting anti-frost control, exiting anti-frost control; wherein, the conditions for exiting anti-frost control include at least one of the following: the indoor heat exchanger temperature is greater than a second preset temperature threshold and lasts for a second preset duration; the temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to a preset deviation threshold; or the cooling mode is turned off or switched.

[0013] Another aspect of the present invention provides an air conditioner control device, comprising: a data acquisition unit, used to acquire operating parameters and environmental parameters of the air conditioner when the outdoor ambient temperature is lower than a preset temperature value and the air conditioner is turned on for cooling; and a judgment unit, used to judge whether the operating parameters and / or the environmental parameters acquired by the data acquisition unit meet preset frosting risk conditions.

[0014] The control unit is configured to adjust the speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner if the judgment unit determines that the operating parameters and / or the environmental parameters meet the preset frost risk conditions.

[0015] Optionally, the operating parameters include at least one of: indoor heat exchanger temperature, return gas pressure, indoor fan speed, outdoor fan speed, and compressor operating frequency; the environmental parameters include at least one of: outdoor ambient temperature, indoor ambient temperature, and indoor ambient humidity; the preset frosting risk conditions include at least one of: the indoor heat exchanger temperature is less than a first preset temperature threshold and continues to decrease within a first preset time period; the return gas pressure is less than a set pressure, wherein the set pressure is the minimum safe return gas pressure set at the current compressor operating frequency; the indoor ambient humidity is greater than a preset humidity threshold and the indoor heat exchanger temperature is less than a second preset temperature threshold.

[0016] Optionally, the control unit adjusts the speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner, including: reducing the speed of the outdoor fan of the air conditioner to a target speed value; wherein the target speed value is determined based on the indoor heat exchanger temperature.

[0017] Optionally, the control unit determines the target rotational speed value based on the indoor heat exchanger temperature, including: calculating the target rotational speed value according to the set outdoor fan speed, the set minimum indoor heat exchanger temperature, and the indoor heat exchanger temperature using the following formula:

[0018]

[0019] in, This refers to the external fan speed. Set the speed of the external fan. The indoor heat exchanger temperature. k is the adjustment coefficient used to set the minimum surface temperature of the indoor heat exchanger.

[0020] Optionally, the adjustment coefficient is determined based on a preset correspondence between the air conditioner's cooling capacity and / or horsepower and the adjustment coefficient.

[0021] Optionally, the control unit is further configured to: if the speed of the external fan has dropped to a preset minimum allowable speed and the temperature of the indoor heat exchanger is less than a first preset temperature threshold, then control the compressor operating frequency to decrease to a preset frequency and control the speed of the indoor fan to increase to a preset speed.

[0022] Optionally, the control unit is further configured to: after performing anti-frost control on the air conditioner, when the operating parameters and / or the environmental parameters meet the conditions for exiting anti-frost control, exit the anti-frost control; wherein the conditions for exiting anti-frost control include at least one of the following: the indoor heat exchanger temperature is greater than a second preset temperature threshold and lasts for a second preset duration; the temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to a preset deviation threshold; or the cooling mode is turned off or switched.

[0023] In another aspect, the present invention provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods described above.

[0024] In another aspect, the present invention provides an air conditioner, including a processor, a memory, and a computer program stored in the memory that can run on the processor, wherein the processor executes the program to implement the steps of any of the methods described above.

[0025] In another aspect, the present invention provides an air conditioner including any of the control devices described above.

[0026] In another aspect, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the steps of any of the methods described above.

[0027] According to the technical solution of the present invention, under low temperature refrigeration conditions, when the risk of frost formation in the air conditioner is detected, the heat dissipation capacity of the condenser is reduced by decreasing the speed of the outdoor fan, the heat dissipation capacity of the condenser side is reasonably controlled, and the heat exchange between the indoor and outdoor sides is balanced, thereby raising the temperature of the indoor heat exchanger (evaporator) to above the freezing point, effectively preventing frost formation on the indoor heat exchanger, while maintaining stable refrigeration output and reducing energy consumption.

[0028] This invention dynamically adjusts the external fan speed to increase the evaporation temperature, thereby suppressing frosting at its thermodynamic source, preventing compressor liquid return and ice blockage, and improving system reliability. It employs gradual adjustment to avoid noise and comfort fluctuations caused by sudden changes in airflow. The invention uses multi-parameter fusion judgment, resulting in a low false alarm rate and adaptability to different climate regions. Furthermore, this invention optimizes the control strategy without relying on electric heating devices, thus reducing cost and power consumption. Attached Figure Description

[0029] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0030] Figure 1 This is a schematic diagram of an embodiment of the air conditioner control method provided by the present invention;

[0031] Figure 2 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention;

[0032] Figure 3 This is a schematic diagram of a specific embodiment of the air conditioner control method provided by the present invention;

[0033] Figure 4 This is a structural block diagram of an embodiment of the air conditioner control device provided by the present invention. Detailed Implementation

[0034] 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 in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] In related technologies, anti-frost measures mainly include: 1) reducing the compressor frequency to reduce the cooling capacity; 2) stopping or reducing the speed of the internal fan; 3) adding electric heating to assist in raising the evaporation temperature. However, the above methods have obvious drawbacks: 1) reducing the compressor frequency affects the cooling capacity and cannot meet the load demand; 2) reducing the speed of the internal fan aggravates uneven airflow, which in turn promotes local frost formation; 3) electric heating has high energy consumption, slow response, and is prone to triggering overheat protection.

[0037] In addition, in the relevant technical control, the outdoor fan mostly adopts a fixed speed or simple temperature control start-stop method, which lacks the ability to dynamically perceive and actively adjust the thermodynamic state of the system, making it difficult to achieve refined anti-frost control.

[0038] This invention provides a method for controlling an air conditioner.

[0039] Figure 1 This is a schematic diagram of an embodiment of the air conditioner control method provided by the present invention.

[0040] like Figure 1 As shown, according to an embodiment of the present invention, the control method includes at least steps S110, S120 and S130.

[0041] Step S110: When the outdoor ambient temperature is lower than the preset temperature value, the operating parameters and environmental parameters of the air conditioner are collected when the air conditioner is turned on for cooling.

[0042] Specifically, under the low-temperature refrigeration condition (i.e., the air conditioner operates in refrigeration when the outdoor ambient temperature is lower than the preset temperature value), the operating parameters of the air conditioner and the indoor and outdoor environmental parameters are collected. The operating parameters may specifically include at least one of the indoor heat exchanger temperature (specifically, the surface temperature of the indoor heat exchanger, for example, the surface temperature of the evaporator) Teva, the suction pressure P 回气 , the speed Nin of the indoor fan, the speed Nout of the outdoor fan, and the operating frequency F of the compressor; the environmental parameters may specifically include at least one of the outdoor ambient temperature Tout, the indoor ambient temperature Tin, and the indoor ambient humidity RH.

[0043] For example, the indoor and outdoor environmental parameters and the operating parameters of the air conditioner system are collected by a parameter collection module. The parameter collection module may specifically include at least one of a temperature sensor, a humidity sensor, and a pressure sensor. The temperature sensor is used to detect the outdoor ambient temperature T out , the indoor ambient temperature T in , and the indoor heat exchanger temperature T eva (the lowest value can be taken by multi-point measurement). The humidity sensor is used to detect the indoor ambient humidity RH; the pressure sensor detects the suction pressure P 回气 . The speeds N in , N out of the indoor and outdoor fans and the operating frequency F of the compressor are obtained in real time during operation. For example, the air conditioner system monitors the real-time operating parameters during operation, and the real-time operating parameters are obtained through monitoring.

[0044] Step S120, determining whether the collected operating parameters and / or the environmental parameters meet the preset frosting risk conditions.

[0045] Specifically, if it is determined that the operating parameters and / or the environmental parameters meet the preset frosting risk conditions, it indicates that the air conditioner has a frosting risk. In a specific embodiment, the preset frosting risk conditions may specifically include at least one of the following:

[0046] (1) The indoor heat exchanger temperature Teva is less than the first preset temperature threshold T1 (Teva < T1) and continuously decreases within the first preset duration;

[0047] That is, the indoor heat exchanger temperature (i.e., the evaporator temperature, specifically, the surface temperature of the evaporator) within the first preset duration is detected, and it is determined whether the indoor heat exchanger temperature continuously decreases within the first preset duration. The first preset temperature threshold can be set between 0°C and 2°C. For example, the first preset temperature threshold T1 = 2°C, and the first preset duration is 3 min. When Teva < 2°C, the surface temperature of the evaporator is detected in real time, and its trend of rising or falling is judged based on the surface temperature data of the evaporator within 3 min.

[0048] Specifically, if it is determined that the temperature Teva of the indoor heat exchanger is less than the first preset temperature threshold T1, it indicates that the temperature of the indoor heat exchanger enters the critical frost formation area. If it is determined that the temperature of the indoor heat exchanger continues to drop within the first preset time period, that is, the change trend of the temperature of the indoor heat exchanger continues to drop, it indicates that the evaporator is about to frost.

[0049] (2)Suction pressure P 回气 Less than the set pressure P set (f);

[0050] That is, P 回气 < P set (f). Wherein, the set pressure P set (f) is the lowest safe suction pressure set at the current compressor operating frequency. If the system suction pressure is lower than the set pressure P set (f), it indicates that the pressure is too low, which may cause a low evaporation temperature, resulting in refrigerant subcooling and frost formation on the evaporator.

[0051] (3)The indoor environmental humidity RH is greater than the preset humidity threshold RH1 and the temperature T of the indoor heat exchanger eva Is less than the second preset temperature threshold T2;

[0052] That is, RH > RH1 and T eva < T2, for example, RH1 = 65%, T2 = 5°C. Considering the synergistic effect of humidity and temperature, the higher the humidity, the higher the dew point temperature. When the indoor environmental temperature is lower than the dew point temperature, condensation will occur. Coupled with a lower evaporation temperature, it is very easy to condense and frost under the action of the indoor fan. The second preset temperature threshold T2 (for example, 5°C) is the key demarcation point between the "dew point temperature of moist air" and the "frost formation risk temperature". The temperature T of the indoor heat exchanger eva Is less than the second preset temperature threshold T2, indicating that there is a risk of frost formation on the evaporator.

[0053] If any of the above three conditions is met, the anti-frost control is triggered to ensure high sensitivity and low false negative rate.

[0054] Step S130, if it is determined that the operating parameter and / or the environmental parameter meets the preset frost formation risk condition, adjust the rotational speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner.

[0055] If any preset frost formation risk condition is met, anti-frost control is performed on the air conditioner by adjusting the rotational speed of the outdoor fan of the air conditioner. Specifically, the rotational speed of the outdoor fan of the air conditioner is reduced to the target rotational speed. Wherein, the target rotational speed value is determined according to the temperature of the indoor heat exchanger. In a specific embodiment, according to the set rotational speed of the outdoor fan, the set minimum surface temperature of the indoor heat exchanger, and the temperature of the indoor heat exchanger, the target rotational speed value is calculated according to the following formula:

[0056]

[0057] in, This refers to the external fan speed. Set the speed of the external fan. The indoor heat exchanger temperature. To set the minimum surface temperature of the indoor heat exchanger, i.e. the minimum evaporator surface temperature that is expected to be maintained, for example, it can be set to 4℃. k is an adjustment coefficient, with a value range of, for example, 0.3~0.6.

[0058] The adjustment coefficient k is determined based on the cooling capacity and / or horsepower of the air conditioner. In one specific embodiment, the adjustment coefficient is determined according to a preset correspondence between the air conditioner's cooling capacity and horsepower and the adjustment coefficient. That is, the adjustment coefficient is determined according to the air conditioner's cooling capacity and / or horsepower, based on the correspondence. Specifically, the correspondence can be a table showing the relationship between cooling capacity and / or horsepower and the adjustment coefficient. This correspondence can be obtained through experimental testing or by statistically analyzing historical data. For example, Table 1 shows a mapping table of adjustment coefficient k and air conditioner cooling capacity and horsepower for different types of air conditioners adjusted according to their horsepower.

[0059] Table 1

[0060]

[0061] According to thermodynamic principles, the relationship between condensing pressure and refrigerant subcooling is as follows: reducing the outdoor fan speed → reducing condenser heat dissipation → increasing condensing pressure → increasing refrigerant subcooling → increasing refrigerant temperature before the expansion valve → increasing evaporation temperature. Experimental data shows that for every 10% reduction in outdoor fan speed, the evaporation temperature can increase by approximately 0.8~1.2℃.

[0062] In one specific implementation, the outdoor fan speed is proportionally reduced to the target speed value. For example, experimental data shows that for every 10% reduction in the rated speed of the outdoor fan, the evaporation temperature can increase by approximately 0.8℃ to 1.2℃. Using the outdoor fan speed as the target output, according to the aforementioned formula, the reduction in outdoor fan speed can be determined simply by controlling the temperature of the indoor heat exchanger. Employing PID closed-loop control, with the outdoor fan speed Nout as the execution variable and the evaporator temperature Teva as the feedback variable, dynamically adjusting the outdoor fan speed can stabilize the indoor heat exchanger temperature Teva between a first preset temperature threshold and a second preset temperature threshold (e.g., between 2℃ and 5℃).

[0063] Further, if the external fan speed has dropped to the preset minimum allowable speed and the temperature of the indoor heat exchanger is less than the first preset temperature threshold (i.e., Teva < T1), the operating frequency of the compressor is controlled to decrease by a preset frequency, and the speed of the internal fan is controlled to increase by a preset speed, so as to enhance the air disturbance on the evaporator surface and prevent the accumulation of local low temperature. When the speed drops to the lowest allowable speed and the evaporator temperature is still lower than the first preset temperature threshold, there is still a risk of frosting. Then, the frosting is further prevented by reducing the operating frequency of the compressor and increasing the speed of the internal fan. At the same time, corresponding prompt information can also be sent, for example, triggering a buzzer or remote alarm to prompt "low temperature frosting risk", and suggesting the user to adjust the set temperature or turn off the refrigeration. The present invention takes the adjustment of the external fan speed as the core means, combines frequency reduction and the increase of the internal fan speed, and realizes a cooperative protection mechanism with the external fan as the main part and the compressor and the internal fan cooperating with each other.

[0064] The preset minimum allowable speed can specifically be the first preset percentage of the rated speed. The first preset percentage is, for example, 30%. The preset frequency can specifically be the second preset percentage of the maximum operating frequency of the compressor. The value range of the second preset percentage can be, for example, 10% - 20%. The preset speed can specifically be the third preset percentage of the maximum speed of the internal fan. The value range of the third preset percentage can be, for example, 10% - 15%. For example, if the external fan speed has dropped to the lowest allowable speed (such as 30% of the rated speed) and the temperature Teva of the indoor heat exchanger is still lower than 2°C, the compressor frequency is further reduced by 10% - 20%, and the speed of the internal fan is increased by 10% - 15% to enhance the air disturbance on the evaporator surface and prevent the accumulation of local low temperature; simultaneously, a buzzer or remote alarm is triggered to prompt "low temperature frosting risk", and it is suggested that the user adjust the set temperature or turn off the refrigeration.

[0065] Figure 2 It is a schematic diagram of the method of another embodiment of the control method of the air conditioner provided by the present invention. As Figure 2 shown, based on the above embodiment, according to another embodiment of the present invention, the method further includes step S140.

[0066] Step S140, when the operating parameter and / or the environmental parameter meets the condition for exiting the anti - frosting control, the anti - frosting control is exited, and the external fan resumes to the normal operating state.

[0067] In a specific embodiment, the condition for exiting the anti - frosting control includes at least one of the following:

[0068] (1) The temperature Teva of the indoor heat exchanger is greater than the second preset temperature threshold T2 (Teva > T2) and lasts for the second preset duration;

[0069] For example, the second preset temperature threshold T2 = 5℃ and the second preset duration is 2 minutes. That is, if Teva > 5℃ and lasts for 2 minutes, the external fan will be gradually restored to normal operation.

[0070] (2) The temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to the preset deviation threshold;

[0071] Specifically, the temperature deviation between the indoor ambient temperature and the set temperature is the absolute value of the temperature difference between the indoor ambient temperature and the set temperature. When the temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to the preset deviation threshold (e.g., deviation ≤ 0.5℃), that is, when the indoor ambient temperature is close to the set temperature, the outdoor fan is controlled to gradually return to normal operation. Normal operation means operating at the rated speed.

[0072] (3) Turn off cooling or switch modes;

[0073] If the user turns off the cooling or climate mode, the outdoor fan will be gradually restored to normal operation.

[0074] The recovery process of gradually restoring the outdoor fan to normal operation adopts a ramp-up speed increase. For example, the speed is increased by the fourth preset percentage of the maximum speed of the outdoor fan within each preset speed increase time, such as increasing the maximum speed of the outdoor fan by 10% every 10 seconds, to avoid sudden changes in system pressure.

[0075] Taking a 24K floor-standing air conditioner as an example, under the cooling conditions on a spring night:

[0076] With an outdoor ambient temperature of 14℃, indoor humidity of 60%, indoor temperature of 27.5℃, and a set temperature of 26℃, after 30 minutes of operation, the system detected a drop in Teva to 1.8℃ and a return gas pressure P. 回气 =0.32MPa, which was determined to be a risk of frosting. Anti-frosting control was initiated, and the outdoor fan speed was gradually reduced from 100% to 55% of the maximum speed. After 5 minutes, Teva temperature rose back to 4.2℃, and the system operated stably without frosting.

[0077] To clearly illustrate the technical solution of the present invention, the execution flow of the air conditioner control method provided by the present invention will be described below with reference to a specific embodiment.

[0078] Figure 3 This is a schematic diagram of a specific embodiment of the air conditioner control method provided by the present invention. Figure 3 The illustrated embodiment includes steps S1 to S5.

[0079] Step S1, when the air conditioner operates in low-temperature refrigeration, collect indoor and outdoor environmental parameters and air conditioner operation parameters. The indoor and outdoor environmental parameters include the outdoor environmental temperature Tout, the indoor environmental temperature Tin, and the indoor environmental humidity RH. The air conditioner operation parameters include the indoor heat exchanger temperature Teva, the suction pressure P 回气 , the indoor fan speed Nin, the outdoor fan speed Nout, and the compressor operation frequency F.

[0080] Step S2, determine whether the frosting risk condition is satisfied. The frosting risk condition includes whether the evaporator surface temperature Teva satisfies Teva < T1 (for example, T1 = 2°C) and continues to decrease, or the suction pressure P 回气 whether satisfies P 回气 < P set (f), P set (f) is the lowest safe suction pressure set at the current frequency, or whether satisfies the indoor environmental humidity RH is greater than the preset humidity threshold (for example, RH > 65%) and the evaporator surface temperature Teva < T2 (for example, T2 = 5°C).

[0081] Step S3, if any frosting risk condition is satisfied, it is determined as the frosting risk state, and enter the anti-frosting control process, dynamically adjust the outdoor fan speed to make the evaporator surface temperature Teva stable between T1 and T2 (for example, 2°C to 5°C); if no frosting risk condition is satisfied, maintain the operation and wait for the next judgment.

[0082] Step S4, if the outdoor fan speed has dropped to the preset minimum speed and the evaporator surface temperature is less than the first preset temperature threshold (that is, Teva < T1), control the compressor operation frequency to decrease by a preset frequency (for example, decrease by 10% to 20% of the maximum compressor operation frequency), control the indoor fan speed to increase by a preset speed (for example, decrease by 10% to 15% of the maximum indoor fan speed), and simultaneously trigger a beeping alarm to prompt the user to intervene.

[0083] Step S5, if the evaporator surface temperature Teva > T2 (for example, Teva > 5°C) and lasts for 2 minutes, or the indoor temperature is close to the set temperature, or the user turns off the refrigeration or switches the mode, exit the anti-frosting control process and resume the normal mode.

[0084] The present invention also provides a control device for an air conditioner.

[0085] Figure 4 is a structural block diagram of an embodiment of the control device for an air conditioner provided by the present invention. As Figure 4 shown, the control device 100 includes: a collection unit 110, a judgment unit 120, and a control unit 130.

[0086] The acquisition unit 110 is configured to collect the operating parameters and environmental parameters of the air conditioner when the outdoor environmental temperature is lower than a preset temperature value and the air conditioner is operating in the cooling mode.

[0087] Specifically, under the low-temperature cooling condition (i.e., the air conditioner operates in the cooling mode when the outdoor environmental temperature is lower than the preset temperature value), the operating parameters of the air conditioner and the indoor and outdoor environmental parameters are collected. The operating parameters may specifically include at least one of the indoor heat exchanger temperature (specifically, the surface temperature of the indoor heat exchanger, for example, the surface temperature of the evaporator) Teva, the suction pressure P 回气 , the speed of the indoor fan Nin, the speed of the outdoor fan Nout, and the compressor operating frequency F; the environmental parameters may specifically include at least one of the outdoor environmental temperature Tout, the indoor environmental temperature Tin, and the indoor environmental humidity RH.

[0088] For example, the indoor and outdoor environmental parameters and the operating parameters of the air conditioner system are collected through a parameter acquisition module. The parameter acquisition module may specifically include at least one of a temperature sensor, a humidity sensor, and a pressure sensor. The temperature sensor is used to detect the outdoor environmental temperature T out , the indoor environmental temperature T in , and the indoor heat exchanger temperature T eva (the lowest value can be obtained by multi-point measurement). The humidity sensor is used to detect the indoor environmental humidity RH; the pressure sensor detects the suction pressure P 回气 . The speeds of the indoor and outdoor fans N in , N out , and the compressor operating frequency F are obtained in real time during operation. For example, the air conditioner system monitors the real-time operating parameters during operation and obtains the real-time operating parameters through monitoring.

[0089] The judgment unit 120 is configured to judge whether the operating parameters and / or the environmental parameters collected by the acquisition unit 110 meet the preset frosting risk conditions.

[0090] Specifically, if it is judged that the operating parameters and / or the environmental parameters meet the preset frosting risk conditions, it indicates that the air conditioner has a frosting risk. In a specific embodiment, the preset frosting risk conditions may specifically include at least one of the following:

[0091] (1) The indoor heat exchanger temperature Teva is less than the first preset temperature threshold T1 (Teva < T1) and continuously decreases within the first preset duration;

[0092] That is, the temperature of the indoor heat exchanger (i.e., the surface temperature of the evaporator) within the first preset duration is detected, and it is determined whether the temperature of the indoor heat exchanger continuously decreases within the first preset duration. For example, the first preset temperature threshold T1 = 2°C, and the first preset duration is 3 min. When Teva < 2°C, the surface temperature of the evaporator is detected in real time, and it is determined whether the trend is upward or downward based on the surface temperature data of the evaporator within 3 min.

[0093] Specifically, if it is determined that the temperature Teva of the indoor heat exchanger is less than the first preset temperature threshold T1, it indicates that the temperature of the indoor heat exchanger enters the critical frost formation area. If it is determined that the temperature of the indoor heat exchanger continuously decreases within the first preset duration, that is, the change trend of the temperature of the indoor heat exchanger continuously decreases, it indicates that the evaporator is about to frost.

[0094] (2) Suction pressure P 回气 Less than the set pressure P set (f);

[0095] That is, P 回气 < P set (f). Among them, the set pressure P set (f) is the lowest safe suction pressure set at the current compressor operating frequency. If the system suction pressure is lower than the set pressure P set (f), it indicates that the pressure is too low, which may cause a low evaporation temperature, resulting in refrigerant subcooling and frost formation on the evaporator.

[0096] (3) The indoor ambient humidity RH is greater than the preset humidity threshold RH1 and the temperature T of the indoor heat exchanger eva Is less than the second preset temperature threshold T2;

[0097] That is, RH > RH1 and T eva < T2. For example, RH1 = 65%, T2 = 5°C. Considering the synergistic effect of humidity and temperature, the higher the humidity, the higher the dew point temperature. When the indoor ambient temperature is lower than the dew point temperature, condensation will occur. Coupled with a relatively low evaporation temperature, it is very easy to condense and frost under the action of the indoor fan. The second preset temperature threshold T2 (such as 5°C) is the key demarcation point between the "dew point temperature of moist air" and the "frost formation risk temperature". The temperature T of the indoor heat exchanger eva Is less than the second preset temperature threshold T2, indicating that there is a risk of frost formation on the evaporator.

[0098] If any of the above three conditions is met, the anti-frost control is triggered to ensure high sensitivity and low false negative rate.

[0099] The control unit 130 is configured to adjust the rotational speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner if the determination unit 120 determines that the operating parameters and / or the environmental parameters meet the preset frost formation risk conditions.

[0100] If any preset frosting risk condition is met, the air conditioner's outdoor fan speed is adjusted to prevent frosting. Specifically, the outdoor fan speed is reduced to a target speed value. This target speed value is determined based on the indoor heat exchanger temperature.

[0101] In one specific implementation, the target rotational speed is calculated according to the following formula, based on the set outdoor fan speed, the set minimum surface temperature of the indoor heat exchanger, and the indoor heat exchanger temperature:

[0102]

[0103] in, This refers to the external fan speed. Set the speed of the external fan. The indoor heat exchanger temperature. To set the minimum surface temperature of the indoor heat exchanger, i.e. the minimum evaporator surface temperature that is expected to be maintained, for example, it can be set to 4℃. k is an adjustment coefficient, with a value range of, for example, 0.3~0.6.

[0104] The adjustment coefficient k is determined based on the cooling capacity and / or horsepower of the air conditioner. In one specific embodiment, the adjustment coefficient is determined according to a preset correspondence between the air conditioner's cooling capacity and horsepower and the adjustment coefficient. That is, the adjustment coefficient is determined according to the air conditioner's cooling capacity and / or horsepower, based on the aforementioned correspondence. Specifically, the correspondence can be a table showing the relationship between cooling capacity and / or horsepower and the adjustment coefficient. For example, Table 1 shows a mapping table of adjustment coefficient k and air conditioner cooling capacity and horsepower for different types of air conditioners adjusted according to their horsepower.

[0105] Table 1

[0106]

[0107] In one specific implementation, the outdoor fan speed is proportionally reduced to the target speed value. Experimental data shows that for every 10% reduction in the rated speed of the outdoor fan, the evaporation temperature can increase by approximately 0.8℃ to 1.2℃. Using the outdoor fan speed as the target output, according to the aforementioned formula, the reduction in outdoor fan speed can be determined simply by controlling the temperature of the indoor heat exchanger. Employing PID closed-loop control, with the outdoor fan speed Nout as the executed variable and the evaporator temperature Teva as the feedback variable, dynamically adjusting the outdoor fan speed can stabilize the indoor heat exchanger temperature Teva between a first preset temperature threshold and a second preset temperature threshold (e.g., between 2℃ and 5℃).

[0108] Further, the control unit 130 is further configured to: if the rotational speed of the external blower has dropped to the preset minimum allowable rotational speed and the temperature of the indoor heat exchanger is lower than the first preset temperature threshold (i.e., Teva < T1), then control the operating frequency of the compressor to decrease by a preset frequency and control the rotational speed of the internal blower to increase by a preset rotational speed, so as to enhance the air disturbance on the evaporator surface and prevent local low temperature accumulation.

[0109] When the rotational speed drops to the minimum allowable rotational speed and the evaporator temperature is still lower than the first preset temperature threshold, there is still a risk of frosting. Then, further prevent frosting by reducing the operating frequency of the compressor and increasing the rotational speed of the internal blower. At the same time, corresponding prompt information can also be sent, for example, triggering a buzzer or remote alarm to prompt "low temperature frosting risk", and suggesting that the user adjust the set temperature or turn off the refrigeration. The present invention takes the adjustment of the rotational speed of the external blower as the core means, combines frequency reduction and increasing the rotational speed of the internal blower, and realizes a collaborative protection mechanism with the external blower as the main and the compressor and the internal blower in coordination.

[0110] The preset minimum allowable rotational speed can specifically be the first preset percentage of the rated rotational speed. The first preset percentage is, for example, 30%. The preset frequency can specifically be the second preset percentage of the maximum operating frequency of the compressor. The value range of the second preset percentage can be, for example, 10% - 20%. The preset rotational speed can specifically be the third preset percentage of the maximum rotational speed of the internal blower. The value range of the third preset percentage can be, for example, 10% - 15%. For example, if the rotational speed of the external blower has dropped to the minimum allowable rotational speed (such as 30% of the rated rotational speed) and the temperature Teva of the indoor heat exchanger is still lower than 2°C, then further reduce the compressor frequency by 10% - 20% and increase the rotational speed of the internal blower by 10% - 15% to enhance the air disturbance on the evaporator surface and prevent local low temperature accumulation; simultaneously, trigger a buzzer or remote alarm to prompt "low temperature frosting risk", and suggest that the user adjust the set temperature or turn off the refrigeration.

[0111] Optionally, the control unit is further configured to: after performing the anti - frosting control on the air conditioner, when the operating parameters and / or the environmental parameters meet the conditions for exiting the anti - frosting control, exit the anti - frosting control, and the external blower resumes to the normal operating state.

[0112] [[ID=1@2]]In a specific implementation manner, the conditions for exiting the anti - frosting control include at least one of the following:

[0113] (1) The temperature Teva of the indoor heat exchanger is greater than the second preset temperature threshold T2 (Teva > T2) and lasts for the second preset duration;

[0114] For example, the second preset temperature threshold T2 = 5°C and the second preset duration is 2 minutes. That is, if Teva > 5°C and lasts for 2 minutes, then gradually resume the external blower to the normal operating state.

[0115] (2) The temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to the preset deviation threshold;

[0116] Specifically, the temperature deviation between the indoor ambient temperature and the set temperature is the absolute value of the temperature difference between the indoor ambient temperature and the set temperature. When the temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to a preset deviation threshold (e.g., deviation ≤ 0.5℃), that is, when the indoor ambient temperature is close to the set temperature, the outdoor fan is controlled to gradually return to normal operation.

[0117] (3) Turn off cooling or switch modes;

[0118] If the user turns off the cooling or climate mode, the outdoor fan will be gradually restored to normal operation.

[0119] The recovery process of gradually restoring the outdoor fan to normal operation adopts a ramp-up speed increase. For example, the speed is increased by the fourth preset percentage of the maximum speed of the outdoor fan within each preset speed increase time, such as increasing the maximum speed of the outdoor fan by 10% every 10 seconds, to avoid sudden changes in system pressure.

[0120] Taking a 24K floor-standing air conditioner as an example, under the cooling conditions on a spring night:

[0121] With an outdoor ambient temperature of 14℃, indoor humidity of 60%, indoor temperature of 27.5℃, and a set temperature of 26℃, after 30 minutes of operation, the system detected a drop in Teva to 1.8℃ and a return gas pressure P. 回气 =0.32MPa, which was determined to be a risk of frosting. Anti-frosting control was initiated, and the outdoor fan speed was gradually reduced from 100% to 55%. After 5 minutes, Teva temperature rose back to 4.2℃, and the system operated stably without frosting.

[0122] The present invention also provides a storage medium corresponding to the control method of the air conditioner, wherein a computer program is stored thereon, and the program, when executed by a processor, implements the steps of any of the aforementioned methods.

[0123] The present invention also provides an air conditioner corresponding to the control method of the air conditioner, comprising a processor, a memory, and a computer program stored in the memory that can run on the processor, wherein the processor executes the program to implement the steps of any of the aforementioned methods.

[0124] The present invention also provides an air conditioner corresponding to the control device of the air conditioner, including the control device of any of the aforementioned air conditioners.

[0125] The present invention also provides a computer program product corresponding to the control method of the air conditioner, including a computer program that, when executed by a processor, implements the steps of any of the aforementioned methods.

[0126] Accordingly, the solution provided by this invention takes the adaptive speed regulation of the external fan as the control core, judges the risk of frosting by multi-parameter fusion, adopts PID closed-loop regulation to improve the evaporation temperature, and combines multi-component collaborative protection to provide a low-temperature cooling anti-frost control method for air conditioners.

[0127] The solution provided by this invention reduces the heat dissipation capacity of the condenser by decreasing the external air volume, balances the heat exchange between the indoor and outdoor sides, and actively suppresses frost formation.

[0128] The solution provided by this invention constructs a frosting risk criterion that integrates multi-dimensional parameters such as evaporator surface temperature, return gas pressure, outdoor ambient temperature, indoor humidity, and compressor frequency, thereby enabling early warning and intelligent decision-making.

[0129] The solution provided by this invention employs a PID closed-loop control algorithm, using the external fan speed as the actuated variable and the evaporator temperature as the feedback quantity to achieve dynamic speed adjustment. Furthermore, when exiting the anti-frost mode, the external fan uses a ramp-up recovery method to avoid sudden changes in system pressure and improve operational stability.

[0130] The solution provided by this invention activates a linkage protection mechanism when the external fan has been reduced to its lowest speed but still cannot suppress frost formation: reducing the compressor frequency and increasing the internal fan speed, enhancing the turbulence on the evaporator surface, and realizing a three-dimensional anti-frost system with the external fan as the main component and multiple components working together.

[0131] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions can be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Other examples and embodiments are within the scope and spirit of this invention and the appended claims. For example, due to the nature of software, the functions described above can be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination thereof. Furthermore, the functional units can be integrated into a single processing unit, or each unit can exist physically separately, or two or more units can be integrated into a single unit.

[0132] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0133] The units described as separate components may or may not be physically separate. Similarly, the components of the control device may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0134] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it 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 related technologies, or all or 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 described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0135] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for controlling an air conditioner, characterized in that, include: When the outdoor ambient temperature is lower than the preset temperature value, the operating parameters of the air conditioner and the environmental parameters are collected when the air conditioner is turned on for cooling. Determine whether the collected operating parameters and / or environmental parameters meet the preset frosting risk conditions; If the operating parameters and / or the environmental parameters are determined to meet the preset frost risk conditions, the speed of the outdoor fan of the air conditioner is adjusted to control the air conditioner against frost.

2. The method according to claim 1, characterized in that, The operating parameters include at least one of the following: indoor heat exchanger temperature, return gas pressure, indoor fan speed, outdoor fan speed, and compressor operating frequency; The environmental parameters include at least one of the following: outdoor ambient temperature, indoor ambient temperature, and indoor ambient humidity; The preset frost risk conditions include at least one of the following: The indoor heat exchanger temperature is lower than the first preset temperature threshold and continues to decrease within the first preset time period; The return gas pressure is less than the set pressure, where the set pressure is the minimum safe return gas pressure set at the current compressor operating frequency; The indoor ambient humidity is greater than the preset humidity threshold and the indoor heat exchanger temperature is less than the second preset temperature threshold.

3. The method according to claim 1, characterized in that, Adjusting the speed of the outdoor fan of the air conditioner to control frost formation includes: The outdoor fan speed of the air conditioner is reduced to a target speed value; wherein the target speed value is determined based on the indoor heat exchanger temperature.

4. The method according to claim 3, characterized in that, Determining the target rotational speed value based on the indoor heat exchanger temperature includes: Based on the set outdoor fan speed, the set minimum indoor heat exchanger temperature, and the indoor heat exchanger temperature, the target speed value is calculated using the following formula: in, This refers to the external fan speed. Set the speed of the external fan. The indoor heat exchanger temperature. k is the adjustment coefficient used to set the minimum surface temperature of the indoor heat exchanger.

5. The method according to claim 4, characterized in that, The adjustment coefficient is determined based on the preset correspondence between the air conditioner's cooling capacity and / or horsepower and the adjustment coefficient.

6. The method according to any one of claims 3-5, characterized in that, Also includes: If the outdoor fan speed has dropped to the preset minimum allowable speed and the indoor heat exchanger temperature is less than the first preset temperature threshold, then the compressor operating frequency is reduced to the preset frequency, and the indoor fan speed is increased to the preset speed.

7. The method according to any one of claims 1-5, characterized in that, Also includes: After the air conditioner is subjected to anti-frost control, the anti-frost control is deactivated when the operating parameters and / or the environmental parameters meet the conditions for deactivating anti-frost control. The conditions for exiting anti-frosting control include at least one of the following: The indoor heat exchanger temperature is greater than the second preset temperature threshold and remains so for the second preset duration; The temperature deviation between the indoor ambient temperature and the set temperature is less than or equal to the preset deviation threshold. Turn off the cooling or switch modes.

8. A control device for an air conditioner, characterized in that, include: The data acquisition unit is used to collect the operating parameters and environmental parameters of the air conditioner when the outdoor ambient temperature is lower than the preset temperature value and the air conditioner is turned on for cooling. The judgment unit is used to determine whether the operating parameters and / or environmental parameters collected by the acquisition unit meet the preset frosting risk conditions. The control unit is configured to adjust the speed of the outdoor fan of the air conditioner to perform anti-frost control on the air conditioner if the judgment unit determines that the operating parameters and / or the environmental parameters meet the preset frost risk conditions.

9. A storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1-7.

10. An air conditioner, characterized in that, It includes a processor, a memory, and a computer program stored in the memory that can run on the processor, wherein the processor executes the program to implement the steps of any of the methods of claims 1-7, or includes the control device as described in claim 8.

11. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1-7.

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