Air conditioner outdoor unit

Abstract

The invention discloses an air conditioner outdoor unit, and relates to the technical field of air conditioners. The air conditioner outdoor unit comprises a condenser, a compressor, an outdoor fan, a coil temperature sensor, an outdoor temperature sensor and a controller. The controller is configured to obtain the outdoor environment temperature detected by the outdoor temperature sensor and the coil pipe temperature detected by the coil pipe temperature sensor, and the difference value between the coil pipe temperature and the outdoor environment temperature is calculated to serve as a first difference value. If the first difference value is larger than or equal to the first set value, the target rotating speed of the outdoor fan is obtained according to the preset corresponding relation between the coil pipe temperature and the rotating speed of the outdoor fan; if the first difference value is smaller than the second set value, the first rotating speed serves as the target rotating speed of the outdoor fan; wherein the absolute value of the difference value between the current rotating speed of the outdoor fan and the first rotating speed is a first threshold value; if the first difference value is smaller than the first set value and larger than or equal to the second set value, the current rotating speed of the outdoor fan serves as the target rotating speed of the outdoor fan. According to the air conditioner outdoor unit, stable control over the rotating speed of the outdoor fan can be achieved under different outdoor environment temperature conditions, the stability of the heat dissipating capacity of the outdoor heat exchanger is guaranteed, and therefore it is guaranteed that the refrigerant pressure in an air conditioner system meets the safe operation condition.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioners, and in particular to an air conditioner outdoor unit. Background Art

[0002] As the refrigerant circulates between the condenser, evaporator and compressor, it transforms between the liquid phase and the gas phase, transferring heat to achieve cooling or heating operation of the air-conditioning system.

[0003] In the prior art, a fan is usually arranged around the condenser, and the operation of the fan increases the air flow speed, thereby increasing the heat exchange efficiency of the condenser. However, if the heat exchange amount between the condenser and the air is too large, the temperature of the refrigerant flowing out of the condenser will be low, which will cause the refrigerant pressure entering the evaporator to be low, which may cause the evaporator to freeze, and may even cause the refrigerant to evaporate incompletely in the evaporator, causing some liquid refrigerant to flow into the compressor and damage the compressor. On the contrary, if the heat exchange amount between the condenser and the air is too small, the temperature of the refrigerant flowing out of the condenser is high, resulting in a high temperature and high pressure of the refrigerant flowing into the evaporator, thereby weakening the heat absorption capacity of the evaporator and poor cooling effect. In addition, if the heat exchange amount between the condenser and the air fluctuates, it is easy to cause the temperature of the refrigerant flowing into the evaporator to be unstable, which will cause the refrigerant pressure in the system to fluctuate, and the compressor operation frequency will follow the high and low, which will not only reduce the service life of the air conditioner, but also seriously affect the user experience. Summary of the invention

[0004] In response to the shortcomings in the related technologies, the present application provides an air-conditioning outdoor unit, which adopts different control strategies to control the operation of the outdoor fan according to the temperature difference between the coil temperature of the outdoor heat exchanger and the outdoor ambient temperature. It can achieve stable control of the outdoor fan speed under different outdoor ambient temperature conditions, ensure the stability of the heat dissipation of the outdoor heat exchanger, and thus ensure that the refrigerant pressure in the air-conditioning system meets the safe operating conditions.

[0005] The present application provides an air conditioner outdoor unit, comprising:

[0006] Condenser, used for exchanging heat with outdoor air;

[0007] The compressor, together with the condenser and the evaporator, forms a refrigerant circulation loop. The compressor is used to compress the low-pressure refrigerant gas into a high-pressure refrigerant gas and drive the refrigerant to flow in the refrigerant circulation loop;

[0008] An outdoor fan, used to drive air into contact with the condenser;

[0009] Coil temperature sensor, used to detect the coil temperature of the condenser;

[0010] Outdoor temperature sensor, used to detect outdoor ambient temperature;

[0011] The controller is connected to the outdoor fan, the coil temperature sensor, and the outdoor temperature sensor respectively; the controller is configured as follows:

[0012] Acquire the outdoor ambient temperature detected by the outdoor temperature sensor and the coil temperature detected by the coil temperature sensor, and calculate the difference between the coil temperature and the outdoor ambient temperature as a first difference;

[0013] If the first difference is greater than or equal to the first set value, the target speed of the outdoor fan is obtained according to the preset corresponding relationship between the coil temperature and the outdoor fan speed;

[0014] If the first difference is less than the second set value, the first speed is used as the target speed of the outdoor fan; wherein the absolute value of the difference between the current speed of the outdoor fan and the first speed is the first threshold;

[0015] If the first difference is less than the first set value and greater than or equal to the second set value, the current rotation speed of the outdoor fan is used as the target rotation speed of the outdoor fan.

[0016] This technical solution calculates the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor to obtain the temperature difference between the coil temperature and the outdoor ambient temperature; according to the temperature difference between the coil temperature and the outdoor ambient temperature, different control strategies are adopted to control the operation of the outdoor fan to ensure the stability of the operating speed of the outdoor fan, thereby ensuring the stability of the heat exchange of the outdoor heat exchanger, and further ensuring the stability of the refrigerant pressure.

[0017] In some of the embodiments, the controller is further configured to: determine the upper limit and lower limit of the outdoor fan speed based on the corresponding relationship between the preset outdoor ambient temperature and the outdoor fan speed; if the target speed of the outdoor fan is less than the lower limit, control the outdoor fan to operate at the lower limit as the actual speed; if the target speed of the outdoor fan is greater than the upper limit, control the outdoor fan to operate at the upper limit as the actual speed; if the target speed of the outdoor fan is greater than or equal to the lower limit and less than or equal to the upper limit, control the outdoor fan to operate with the target speed as the actual speed.

[0018] The technical solution determines the upper and lower limits of the rotation speed of the outdoor fan according to the outdoor ambient temperature, and uses the upper and lower limits to limit the target rotation speed of the outdoor fan to avoid instability and unsafe operation of the air conditioner caused by abnormal coil temperature.

[0019] In some of the embodiments, the controller is further configured as follows: when the first difference is greater than or equal to the first set value, if the difference between the current speed of the outdoor fan and the target speed is less than or equal to the second threshold, the speed of the outdoor fan is controlled to operate with the target speed as the actual speed; if the difference between the current speed of the outdoor fan and the target speed is greater than the second threshold, the outdoor fan is controlled to finally operate with the second speed as the actual speed; wherein the difference between the current speed of the outdoor fan and the second speed is the second threshold.

[0020] This technical solution limits the target speed of the outdoor fan determined according to the coil temperature. When the difference between the current speed of the outdoor fan and the target speed is greater than a second threshold, the outdoor fan is controlled to finally operate at the second speed as the target speed to prevent the target speed from being too different from the current speed of the outdoor fan, resulting in an excessively large change rate of the outdoor fan.

[0021] In some of the embodiments, the controller is further configured to: when the first difference is greater than or equal to the first set value, if the target speed is less than the current speed of the outdoor fan, control the speed of the outdoor fan to change by at most a third threshold value.

[0022] This technical solution limits the variation range of the outdoor fan speed to prevent large changes in the outdoor fan speed from causing unsafe operation of the outdoor fan and refrigerant pressure fluctuations.

[0023] In some of the embodiments, the controller is configured to: determine the changing trend of the coil temperature based on the detection value of the coil temperature sensor; when the first difference is greater than or equal to the first set value, determine the operating speed of the outdoor fan based on the changing trend of the coil temperature and the detection value of the coil temperature sensor.

[0024] In the technical solution, by determining the operating speed of the outdoor fan according to the change trend of the coil temperature, the outdoor fan can have a better heat dissipation effect on the outdoor heat exchanger.

[0025] In some of the embodiments, the controller is further configured to: if the coil temperature changes in a stable trend, control the outdoor fan to continue to operate at the current speed.

[0026] The stable trend of the coil temperature in this technical solution indicates that the current speed of the outdoor fan meets the heat dissipation requirements of the outdoor heat exchanger. Controlling the outdoor fan to continue running at the current speed of the outdoor fan can maintain the current heat dissipation effect of the outdoor heat exchanger.

[0027] In some of the embodiments, when the first difference is the same, the target rotation speed determined when the temperature of at least part of the coil changes in an upward trend is smaller than the target rotation speed determined when the temperature of at least part of the coil changes in a downward trend.

[0028] In the technical solution, by making the target speed determined when the temperature of at least part of the coil changes in an upward trend lower than the target speed determined when the temperature of at least part of the coil changes in a downward trend, the target speed of the outdoor fan can be different according to the different trends of the coil temperature changes, so that the outdoor fan can have a better heat dissipation effect.

[0029] In some of the embodiments, the controller is configured to: determine the initial rotation speed of the outdoor fan according to the outdoor ambient temperature detected by the outdoor temperature sensor when the outdoor unit of the air conditioner starts cooling operation;

[0030] After the outdoor fan is controlled to run at an initial speed for a preset time, the detection value of the coil temperature sensor is obtained.

[0031] The technical solution determines the initial speed of the outdoor fan according to the outdoor ambient temperature, and obtains the detection value of the coil temperature sensor after the outdoor fan runs at the initial speed for a preset time, so as to ensure the accuracy of the detection value of the coil temperature sensor.

[0032] In some of the embodiments, the controller is configured as follows: among the initial speed of the outdoor fan, the upper limit value of the outdoor fan speed and the lower limit value of the outdoor fan speed determined based on the detection value of the same outdoor temperature sensor, the initial speed of the outdoor fan is greater than or equal to the upper limit value of the outdoor fan speed, and the initial speed of the outdoor fan is less than or equal to the lower limit value of the outdoor fan speed.

[0033] In the present technical scheme, the parameters determined according to the detection value of the same outdoor temperature sensor include: the initial speed of the outdoor fan, the upper limit value of the outdoor fan speed and the lower limit value of the outdoor fan speed. By making the initial speed of the outdoor fan greater than or equal to the upper limit value of the outdoor fan speed and the initial speed of the outdoor fan less than or equal to the lower limit value of the outdoor fan speed, the upper limit value and the lower limit value can limit the target speed of the outdoor fan.

[0034] In addition, the present application also provides an air conditioner outdoor unit, comprising:

[0035] Condenser, used for exchanging heat with outdoor air;

[0036] The compressor, together with the condenser and the evaporator, forms a refrigerant circulation loop. The compressor is used to compress the low-pressure refrigerant gas into a high-pressure refrigerant gas and drive the refrigerant to flow in the refrigerant circulation loop;

[0037] The outdoor fan is used to drive the air to contact the condenser; the outdoor fan has multiple gears, and each gear has a corresponding speed;

[0038] Coil temperature sensor, used to detect coil temperature;

[0039] Outdoor temperature sensor, used to detect outdoor ambient temperature;

[0040] A controller is connected to the outdoor fan, the coil temperature sensor and the outdoor temperature sensor respectively; the controller is configured as follows:

[0041] Acquire a detection value of an outdoor temperature sensor and a detection value of a coil temperature sensor, and calculate a difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor as a first difference;

[0042] Determining an initial target gear position of the outdoor fan according to a relationship between the first difference and the set value;

[0043] The initial target gear position of the outdoor fan is corrected, the final target gear position of the outdoor fan is obtained, and the outdoor fan is controlled to continue to operate at the final target gear position.

[0044] The technical solution calculates the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor to obtain the temperature difference between the coil temperature and the outdoor ambient temperature; determines the initial target gear position of the outdoor fan according to the temperature difference between the coil temperature and the outdoor ambient temperature, and corrects the initial target gear position of the outdoor fan to ensure the stability of the operating speed of the outdoor fan, thereby ensuring the stability of the heat exchange of the outdoor heat exchanger, and further ensuring the stability of the refrigerant pressure.

[0045] The above-mentioned air-conditioning outdoor unit adopts different control strategies to control the operation of the outdoor fan according to the temperature difference between the coil temperature of the outdoor heat exchanger and the outdoor ambient temperature. It can achieve stable control of the outdoor fan speed under different outdoor ambient temperature conditions, ensure the stability of the heat dissipation of the outdoor heat exchanger, and thus ensure that the refrigerant pressure in the air-conditioning system meets the safe operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram showing the flow of refrigerant when the outdoor unit of an air conditioner is in a cooling mode according to some embodiments;

[0047] Figure 2 A schematic diagram showing the flow of refrigerant when the outdoor unit of an air conditioner is in a heating mode according to some embodiments;

[0048] Figure 3 The control flow chart for determining the target speed of the outdoor fan in the air conditioner outdoor unit of the present application is exemplarily shown;

[0049] Figure 4 A control principle diagram for correcting the target speed in the air conditioner outdoor unit of the present application is shown;

[0050] Figure 5 The flowchart for judging the temperature variation trend of the coil in the outdoor unit of the air conditioner of the present application is shown as an example;

[0051] Figure 6 The control principle diagram of using the upper limit value and the lower limit value to correct the target speed in the air conditioner outdoor unit of the present application is exemplarily shown;

[0052] Figure 7 The control flow chart of the final speed of the outdoor fan in the air conditioner outdoor unit of the present application is exemplarily shown;

[0053] Figure 8 The working process of the air conditioner outdoor unit of the present application is shown as an example Figure 1 ;

[0054] Fig. 9 The working process of the air conditioner outdoor unit of the present application is shown as an example Figure 2 ;

[0055] Fig.10 A schematic diagram showing, by way of example, the upper limit gear position and the lower limit gear position of the outdoor fan at different outdoor ambient temperatures in one embodiment of the air-conditioning outdoor unit of the present application;

[0056] Fig.11 The control flow chart of the outdoor fan gear position in the air-conditioning outdoor unit of the present application is exemplified. DETAILED DESCRIPTION

[0057] In order to make the purpose and implementation method of the present application clearer, the exemplary implementation method of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0058] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and common meanings.

[0059] The terms "first", "second", "third", etc. in the specification and claims of this application and the above drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean to limit a specific order or sequence, unless otherwise noted. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances.

[0060] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0061] The air-conditioning outdoor unit provided in the embodiments of the present application may have various implementation forms, for example, it may be an outdoor unit of a wall-mounted air conditioner, an outdoor unit of a cabinet air conditioner, etc.

[0062] The air conditioner includes an indoor unit, which is usually located indoors. The indoor unit includes an indoor heat exchanger, which is located indoors and is used to exchange heat with indoor air, thereby heating or cooling the indoor environment.

[0063] The air conditioner includes an outdoor air conditioner, which is usually arranged outdoors. The outdoor air conditioner includes an outdoor heat exchanger, which is arranged outdoors and is used to exchange heat with outdoor air.

[0064] The air conditioner outdoor unit includes a compressor, and the compressor, outdoor heat exchanger and indoor heat exchanger together form a refrigerant circulation loop; the compressor is used to compress the refrigerant in a low-pressure state into a high-pressure state, and drive the refrigerant to circulate in the refrigerant circulation loop, so that the indoor heat exchanger can cool or heat the indoor air.

[0065] like Figure 1 As shown in the figure, when the outdoor unit of the air conditioner cools the indoor environment, the outdoor heat exchanger works as a condenser and the indoor heat exchanger works as an evaporator. After being compressed by the compressor, the refrigerant flows into the outdoor heat exchanger to release heat, then flows into the indoor heat exchanger to absorb heat, and finally flows into the compressor.

[0066] like Figure 2 As shown in the figure, when the outdoor unit of the air conditioner heats the indoor environment, the outdoor heat exchanger works as an evaporator and the indoor heat exchanger works as a condenser. After being compressed by the compressor, the refrigerant flows into the indoor heat exchanger to release heat, then flows into the outdoor heat exchanger to absorb heat, and finally flows into the compressor.

[0067] When the air conditioner is in cooling operation, the outdoor heat exchanger exchanges heat with the outdoor air, which reduces the temperature of the refrigerant flowing out of the outdoor heat exchanger. When the heat exchanged between the outdoor heat exchanger and the outdoor air is large, the temperature of the refrigerant flowing out of the outdoor heat exchanger is low, and accordingly, the temperature of the refrigerant flowing into the indoor heat exchanger is also low. The refrigerant requires more heat to evaporate in the indoor heat exchanger, and the indoor heat exchanger is prone to freezing. On the other hand, if the indoor heat exchanger does not absorb enough heat, the refrigerant in the indoor heat exchanger will not evaporate completely, causing some liquid refrigerant to flow into the compressor, which is easy to damage the compressor.

[0068] When the heat exchanged between the outdoor heat exchanger and the outdoor air is small, the temperature of the refrigerant flowing out of the outdoor heat exchanger is high, and the corresponding temperature of the refrigerant flowing into the indoor heat exchanger is high. The heat required for the refrigerant to evaporate in the indoor heat exchanger is small, and the heat exchange between the indoor heat exchanger and the indoor air is small, and the effect of lowering the temperature cannot be achieved.

[0069] In addition, when the refrigerant temperature is low, the refrigerant pressure is also correspondingly low, and when the refrigerant temperature is high, the refrigerant pressure is also correspondingly high. If the heat exchange rate between the outdoor heat exchanger and the outdoor air fluctuates and is unstable, it will easily cause the refrigerant pressure in the refrigerant circulation loop to fluctuate, and the operating frequency of the compressor will also fluctuate, which will not only reduce the service life of the air conditioner, but also provide a poor user experience.

[0070] In the prior art, the outdoor unit of the air conditioner includes an outdoor fan, which is used to increase the heat exchange effect of the outdoor heat exchanger; the operation of the outdoor fan causes air to flow, thereby increasing the heat exchange effect between the air and the outdoor heat exchanger.

[0071] The outdoor fan has an important influence on the heat exchange effect between the outdoor heat exchanger and the outdoor air. Generally, the faster the outdoor fan speed is, the higher the air flow rate is, the greater the heat exchange between the outdoor heat exchanger and the outdoor air is, and the better the heat exchange effect of the outdoor heat exchanger is; the slower the outdoor fan speed is, the lower the air flow rate is, the smaller the heat exchange between the outdoor heat exchanger and the outdoor air is, and the worse the heat exchange effect of the outdoor heat exchanger is.

[0072] In the present application, when the air conditioner cools the indoor environment, the speed of the outdoor fan is adjusted and controlled to ensure the stability of the heat exchange between the outdoor heat exchanger and the outdoor air, thereby preventing refrigerant pressure fluctuations and further preventing the compressor operating frequency from being unstable.

[0073] When the outdoor ambient temperature is the same, if the coil temperature of the outdoor heat exchanger is high and the temperature difference between the coil temperature of the outdoor heat exchanger and the outdoor ambient temperature is large, it is necessary to increase the outdoor fan speed and increase the heat exchange effect between the outdoor heat exchanger and the air to prevent the refrigerant temperature from being too high, thereby ensuring the refrigerant pressure is stable; if the coil temperature of the outdoor heat exchanger is low and the temperature difference between the coil temperature of the outdoor heat exchanger and the outdoor ambient temperature is small, it is necessary to reduce the outdoor fan speed and reduce the heat exchange effect between the outdoor heat exchanger and the air to prevent the refrigerant from being over-cooled, thereby ensuring the refrigerant pressure is stable.

[0074] In the present application, the operation of the outdoor fan is controlled according to two parameters, namely, the outdoor ambient temperature and the coil temperature of the outdoor heat exchanger, so as to achieve effective control of the outdoor fan.

[0075] The air conditioner outdoor unit includes an outdoor temperature sensor, and the outdoor temperature sensor is used to detect the outdoor ambient temperature.

[0076] The outdoor unit of the air conditioner includes a coil temperature sensor, which is used to detect the coil temperature of the outdoor heat exchanger.

[0077] In the present application, the temperature difference between the coil temperature and the outdoor ambient temperature is obtained by calculating the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor; according to the temperature difference between the coil temperature and the outdoor ambient temperature, different control strategies are adopted to control the operation of the outdoor fan to ensure the stability of the operating speed of the outdoor fan, thereby ensuring the stability of the heat exchange of the outdoor heat exchanger, and further ensuring the stability of the refrigerant pressure.

[0078] The air conditioner outdoor unit comprises a controller, which is respectively connected with an outdoor temperature sensor, a coil temperature sensor and an outdoor fan.

[0079] like Figure 3 As shown, the controller is configured to: obtain the detection value of the outdoor temperature sensor as the outdoor ambient temperature, obtain the detection value of the coil temperature sensor as the coil temperature of the outdoor heat exchanger, and calculate the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor as the first difference T1; determine the target speed Vs of the outdoor fan according to the relationship between the first difference T1 and the first set value S1 and the second set value S2; and control the outdoor fan to finally operate at the target speed Vs.

[0080] It should be noted that when the air conditioner is in cooling operation, the coil temperature of the outdoor heat exchanger is higher than the outdoor ambient temperature. When the temperature difference between the coil temperature and the outdoor ambient temperature is too large, the current speed Vt of the outdoor fan cannot meet the current heat dissipation requirement of the outdoor heat exchanger, and the outdoor fan speed needs to be increased; when the temperature difference between the coil temperature and the outdoor ambient temperature is too small, the current speed Vt of the outdoor fan exceeds the current heat dissipation requirement of the outdoor heat exchanger, and the speed of the outdoor fan is too high, and the speed of the outdoor fan needs to be reduced; when the temperature difference between the coil temperature and the outdoor ambient temperature is within a certain range, the current speed Vt of the outdoor fan meets the current heat dissipation requirement of the outdoor heat exchanger, and the outdoor fan can maintain the current speed Vt.

[0081] Specifically, the controller is configured to: if the first difference T1 is greater than or equal to the first set value S1, determine the target speed Vs of the outdoor fan according to the detection value of the coil temperature sensor. It should be noted that in this application, a corresponding relationship between the coil temperature and the target speed of the outdoor fan is preset, and the coil temperature can be obtained according to the detection value of the coil temperature sensor, and the target speed of the outdoor fan at the coil temperature is determined according to the coil temperature.

[0082] The first difference T1 is greater than or equal to the first set value S1, indicating that the temperature difference between the coil temperature and the outdoor ambient temperature is large, and the current speed Vt of the outdoor fan cannot meet the heat dissipation requirements. The speed of the outdoor fan needs to be increased to ensure the stability of the refrigerant pressure.

[0083] The controller is further configured to: if the first difference T1 is less than the second set value S2, the first speed is used as the target speed Vs of the outdoor fan, and the difference between the first speed and the current speed Vt of the outdoor fan is used as the first threshold.

[0084] The first difference T1 is smaller than the second set value S2, indicating that the temperature difference between the coil temperature and the outdoor ambient temperature is small, and the speed of the outdoor fan needs to be reduced to ensure the stability of the refrigerant pressure.

[0085] The controller is further configured to: if the first difference T1 is less than the first set value S1 and greater than or equal to the second set value S2, control the outdoor fan to use the current speed Vt as the target speed Vs of the outdoor fan, and control the outdoor fan to continue to operate at the current speed Vt.

[0086] The first difference T1 is less than the first set value S1 and greater than or equal to the second set value S2, indicating that the temperature difference between the coil temperature and the outdoor ambient temperature is within the required range, and the current speed Vt of the outdoor fan can meet the heat exchange requirements of the air conditioner. Controlling the outdoor fan to continue running at the current speed Vt can ensure the normal operation of the air conditioner.

[0087] The transition time of the outdoor fan from the current speed Vt to the target speed Vs is usually short. If the difference between the target speed Vs and the current speed Vt is too large, the speed change rate of the outdoor fan will be large, which may easily reduce the safety, reliability and stability of the outdoor fan.

[0088] Based on this, the target speed Vs of the outdoor fan is limited in the present application to prevent the gap between the current speed Vt and the target speed Vs from being too large, thereby causing refrigerant pressure fluctuations.

[0089] like Figure 4 As shown, the controller is configured as follows: when the first difference T1 is greater than or equal to the first set value S1, the difference between the current speed Vt and the target speed Vs is calculated as the second difference T2; if the second difference T2 is less than or equal to the second threshold, the speed of the outdoor fan is controlled to operate with the target speed Vs as the actual speed; if the second difference T2 is greater than the second threshold, the outdoor fan is controlled to operate with the second speed V2 as the target speed Vs for final operation; wherein the difference between the current speed Vt and the second speed V2 is the second threshold.

[0090] When determining the target speed Vs of the outdoor fan according to the coil temperature, if the second difference T2 is greater than the second threshold, the outdoor fan is controlled to perform final operation with the second speed V2 as the target speed Vs to prevent the target speed Vs from being too different from the current speed Vt, which would cause the outdoor fan to change too fast, thus easily reducing the safety of the outdoor fan operation. In addition, large changes in the outdoor fan speed would easily lead to a large change rate of the heat exchange of the outdoor heat exchanger, which would easily cause refrigerant pressure fluctuations and lead to unstable operation of the air conditioner.

[0091] In some embodiments of the present application, in order to prevent the outdoor fan speed from changing greatly, the speed change of the outdoor fan is limited to prevent the speed change rate of the outdoor fan from being too large, which will cause the heat dissipation of the outdoor heat exchanger to change greatly, thereby causing the refrigerant pressure to fluctuate, and further causing the air conditioner to operate unstable.

[0092] Specifically, the controller is configured to: control the speed of the outdoor fan to change in decrements by multiples of a first threshold; when the first difference T1 is greater than or equal to a first set value S1, control the speed of the outdoor fan to change in decrements by at most a third threshold; when the first difference T1 is less than a second set value S2, control the speed of the outdoor fan to change in decrements by at most the first threshold.

[0093] The changing trend of coil temperature is usually divided into three trends: rising, falling and stable. According to the changing trend of coil temperature, it can be inferred that the heat exchange of outdoor heat exchanger is also divided into three trends: rising, falling and stable. The changing trend of heat exchange of outdoor heat exchanger is the same as the changing trend of coil temperature and is affected by the changing trend of coil temperature.

[0094] Under the same coil temperature, when the coil temperature shows different change trends, the change in the heat exchange of the outdoor heat exchanger is also different, and the target speed Vs of the outdoor fan is also different accordingly. Therefore, by obtaining the change trend of the coil temperature, the change trend of the heat exchange of the outdoor heat exchanger can be predicted. Determining the operating speed of the outdoor fan according to the change trend of the heat exchange of the outdoor heat exchanger can make the outdoor fan have a better heat dissipation effect on the outdoor heat exchanger.

[0095] Specifically, the controller is configured to: regularly obtain the detection value of the coil temperature sensor, and judge the changing trend of the coil temperature according to the detection value of the coil temperature sensor; when the first difference T1 is greater than or equal to the first set value S1, determine the operating speed of the outdoor fan according to the changing trend of the coil temperature and the detection value of the coil temperature sensor.

[0096] It should be noted that when the detection values ​​of the coil temperature sensor are the same but the coil temperature presents different change trends, the target speed Vs of the outdoor fan is determined to be different.

[0097] like Figure 5As shown, the controller is configured to: obtain the detection value P1 of the coil temperature sensor at the current moment and the detection value P2 of the coil temperature sensor at the next moment, calculate the absolute value of the difference between the two as the third difference T3, if the detection value P1 of the coil temperature sensor at the current moment is less than the detection value P2 at the next moment and the third difference T3 is greater than or equal to the first reference value C1, then it is determined that the change of the coil temperature is an upward trend; if the detection value P1 of the coil temperature sensor at the current moment is greater than the detection value P2 at the next moment and the third difference T3 is greater than or equal to the first reference value C1, then it is determined that the change of the coil temperature is a downward trend; if the absolute value of the difference between the detection value P1 of the coil temperature sensor at the current moment and the detection value P2 at the next moment is less than the first reference value C1, then it is determined that the change of the coil temperature is a stable trend.

[0098] Theoretically, when the first difference T1 is the same, the target speed Vs of the outdoor fan determined when the same coil temperature is on an upward trend is different from the target speed Vs of the outdoor fan determined when the same coil temperature is on a downward trend. However, in actual applications, there are also some cases where the target speed Vs of the outdoor fan determined when the coil temperature is on an upward trend is the same as the target speed Vs of the outdoor fan determined when the same coil temperature is on a downward trend.

[0099] For the convenience of expression, the outdoor fan target speed Vs determined when the coil temperature changes in an upward trend is called an upward target speed Vss, and the outdoor fan target speed Vs determined when the coil temperature changes in a downward trend is called a downward target speed Vsj.

[0100] Theoretically, when the first difference T1 is the same, the rising target speed Vss determined by the same coil temperature is smaller than the falling target speed Vsj. However, in actual applications, there are also some coil temperatures where the rising target speed Vss is the same as the falling target speed Vsj.

[0101] It should be noted that when the coil temperature changes in a stable trend, it means that the heat exchange of the outdoor heat exchanger is in a stable trend and the refrigerant pressure is also in a stable trend. Therefore, the current speed Vt of the outdoor fan meets the operating requirements of the air conditioner.

[0102] The controller is configured to control the outdoor fan to continue running at the current speed Vt if the coil temperature changes in a stable trend.

[0103] When the air conditioner starts to run, the coil temperature may be temporarily abnormal. When the coil temperature is abnormal, the first difference T1 is likely to have a large error, making the target speed Vs of the outdoor fan inaccurate. Therefore, in this application, the target speed Vs of the outdoor fan is limited to an upper limit value Vmax and a lower limit value Vmin to ensure the safety, reliability and stability of the outdoor fan, thereby ensuring the safety, reliability and stability of the air conditioner.

[0104] Specifically, Figure 6 As shown, the controller is configured as follows: determining the upper limit Vmax and lower limit Vmin of the outdoor fan speed according to the detection value of the outdoor temperature sensor; when the target speed Vs of the outdoor fan is less than the lower limit Vmin, controlling the outdoor fan to operate at the lower limit Vmin as the speed; when the target speed Vs of the outdoor fan is greater than the upper limit Vmax, controlling the outdoor fan to operate at the upper limit Vmax as the speed; when the target speed Vs of the outdoor fan is greater than or equal to the lower limit Vmin and less than or equal to the upper limit Vmax, controlling the outdoor fan to operate at the target speed Vs.

[0105] It should be noted that in the present application, a correspondence between the outdoor ambient temperature and the outdoor fan speed is preset. The outdoor ambient temperature can be known according to the detection value of the outdoor temperature sensor, thereby determining the outdoor fan speed corresponding to the outdoor ambient temperature.

[0106] By determining the upper limit Vmax and lower limit Vmin of the outdoor fan speed according to the outdoor ambient temperature, the upper limit Vmax and lower limit Vmin are used to limit the target speed Vs of the outdoor fan to avoid instability and unsafe operation of the air conditioner caused by abnormal coil temperature.

[0107] like Figure 7 As shown, the control process of the outdoor fan in the above-mentioned air-conditioning outdoor unit is: determine the initial target speed Vs1 of the outdoor fan, then correct the initial target speed Vs1 of the outdoor fan to obtain the intermediate target speed Vs2 of the outdoor fan, and finally use the upper limit value Vmax and the lower limit value Vmin of the outdoor fan speed to correct the intermediate target speed Vs2 of the outdoor fan to obtain the final target speed Vs3 of the outdoor fan.

[0108] It should be noted that when the air conditioner is in cooling operation, the outdoor fan is initially operated at an initial speed V0 to allow air to flow around the outdoor heat exchanger, thereby making the detected coil temperature more accurate.

[0109] In the present application, the initial speed V0 of the outdoor fan is determined according to the outdoor ambient temperature. After the outdoor fan runs at the initial speed V0 for a preset time, the detection value of the coil temperature sensor is obtained to ensure the accuracy of the detection value of the coil temperature sensor.

[0110] The controller is configured to: determine the initial speed of the outdoor fan according to the outdoor ambient temperature detected by the outdoor temperature sensor when the air conditioner outdoor unit starts cooling operation; and obtain the detection value of the coil temperature sensor after controlling the outdoor fan to run at the initial speed for a preset time.

[0111] It should be noted that, the higher the outdoor ambient temperature, the greater the initial rotation speed V0 of the outdoor fan; and the lower the outdoor ambient temperature, the smaller the initial rotation speed V0 of the outdoor fan.

[0112] It should also be noted that when the air conditioner just starts cooling operation, the speed of the outdoor fan is the initial speed V0. After a logical judgment is made on the speed of the outdoor fan, the actual speed of the outdoor fan may change. During the cooling operation of the air conditioner, the control logic of the outdoor fan speed makes a judgment at regular intervals to ensure the control effect of the outdoor fan speed.

[0113] In the present application, the variables determined according to the parameter of outdoor ambient temperature include at least three, namely, the initial speed V0 of the outdoor fan, the upper limit value Vmax of the outdoor fan speed and the lower limit value Vmin of the outdoor fan speed. Among them, among the three variables determined by the same outdoor ambient temperature, the initial speed V0 of the outdoor fan is greater than the upper limit value Vmax of the outdoor fan speed, the initial speed V0 of the outdoor fan is less than or equal to the lower limit value Vmin of the outdoor fan speed, and the upper limit value Vmax of the outdoor fan speed is less than or equal to the lower limit value Vmin of the outdoor fan speed.

[0114] During the cooling operation of the air-conditioning outdoor unit, the operation process of the outdoor fan is roughly divided into two processes: preliminary operation and actual operation. During the preliminary operation, the outdoor fan operates at an initial speed V0; during the actual operation, the outdoor fan operates at a final target speed Vs3.

[0115] It should be noted that during actual operation, the controller uses different control logics to adjust and control the final target speed Vs3 of the outdoor fan according to the outdoor ambient temperature, coil temperature and the current speed Vt of the outdoor fan. The final target speed Vs3 is not a fixed value.

[0116] It should also be noted that the process in which the controller adjusts and controls the rotation speed of the outdoor fan includes multiple controls of the outdoor fan, and the multiple controls of the outdoor fan by the controller are performed in chronological order.

[0117] The following takes the example of the controller controlling the speed of the outdoor fan twice to introduce the control principle of the controller in detail.

[0118] like Figure 8 As shown, the controller is configured to: obtain the detection value of the outdoor temperature sensor when the air-conditioning outdoor unit is in initial cooling operation, and determine the initial speed V0 of the outdoor fan, the upper limit value Vmax of the outdoor fan speed, and the lower limit value Vmin of the outdoor fan speed according to the detection value of the outdoor temperature sensor.

[0119] The controller is further configured to: obtain the detection value of the coil temperature sensor after the outdoor fan runs at an initial speed V0 for a preset time, calculate the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor as the first difference T1, and obtain the change trend of the coil temperature.

[0120] The controller is further configured to: determine the initial target speed Vs1 of the outdoor fan based on the relationship between the first difference T1 and the first set value S1 and the second set value S2; determine the intermediate target speed Vs2 of the outdoor fan based on the relationship between the initial target speed Vs1 of the outdoor fan and the initial speed V0 of the outdoor fan; determine the final target speed Vs3 of the outdoor fan based on the relationship between the intermediate target speed Vs2 of the outdoor fan and the upper limit value Vmax and the lower limit value Vmin of the outdoor fan speed.

[0121] When determining the initial target speed Vs1 of the outdoor fan, the controller is configured as follows: if the first difference T1 is greater than or equal to the first set value S1, the initial target speed Vs1 of the outdoor fan is determined according to the detection value of the coil temperature sensor and the changing trend of the coil temperature; if the first difference T1 is less than the second set value S2, the first speed V1 is used as the initial target speed Vs1 of the outdoor fan, and the difference between the first speed V1 and the initial speed V0 is used as the first threshold; if the first difference T1 is less than the first set value S1 and greater than or equal to the second set value S2, the initial speed V0 is used as the initial target speed Vs1 of the outdoor fan.

[0122] When determining the intermediate target speed Vs2, the controller is further configured as follows: when the first difference T1 is greater than or equal to the first set value S1, if the initial speed V0 is greater than the initial target speed Vs1 and the difference between the two is greater than the second threshold, the outdoor fan is controlled to use the second speed V2 as the intermediate target speed Vs2; wherein the difference between the initial speed V0 and the second speed V2 is the second threshold; if the difference between the two is less than the second threshold, the outdoor fan is controlled to use the initial target speed Vs1 as the intermediate target speed Vs2. When the first difference T1 is less than the second set value S2, the outdoor fan is controlled to use the first speed V1 as the intermediate target speed Vs2.

[0123] When determining the final target speed Vs3 of the outdoor fan, the controller is configured as follows: when the initial target speed Vs1 of the outdoor fan is less than the lower limit value Vmin, the outdoor fan is controlled to use the lower limit value Vmin as the final target speed Vs3; when the initial target speed Vs1 of the outdoor fan is greater than the upper limit value Vmax, the outdoor fan is controlled to use the upper limit value Vmax as the final target speed Vs3; when the initial target speed Vs1 of the outdoor fan is greater than or equal to the lower limit value Vmin and less than or equal to the upper limit value Vmax, the outdoor fan is controlled to use the initial target speed Vs1 as the final target speed Vs3.

[0124] The controller is further configured to control the outdoor fan to operate at the final target speed Vs3. So far, the controller has completed the first control of the speed of the outdoor fan.

[0125] like Fig. 9 As shown, the controller is further configured to: obtain the detection value of the coil temperature sensor again, calculate the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor as the first difference T1, and obtain the change trend of the coil temperature.

[0126] The controller is further configured to: determine the initial target speed Vs1 of the outdoor fan based on the relationship between the first difference T1 and the first set value S1 and the second set value S2; determine the intermediate target speed Vs2 of the outdoor fan based on the relationship between the initial target speed Vs1 of the outdoor fan and the current speed Vt of the outdoor fan; determine the final target speed Vs3 of the outdoor fan based on the relationship between the intermediate target speed Vs2 of the outdoor fan and the upper limit Vmax and lower limit Vmin of the outdoor fan speed.

[0127] When determining the initial target speed Vs1 of the outdoor fan, the controller is configured as follows: if the first difference T1 is greater than or equal to the first set value S1, the initial target speed Vs1 of the outdoor fan is determined according to the detection value of the coil temperature sensor and the changing trend of the coil temperature; if the first difference T1 is less than the second set value S2, the first speed V1 is used as the initial target speed Vs1 of the outdoor fan, and the difference between the first speed V1 and the current speed Vt is used as the first threshold value; if the first difference T1 is less than the first set value S1 and greater than or equal to the second set value S2, the current speed Vt is used as the initial target speed Vs1 of the outdoor fan.

[0128] When determining the intermediate target speed Vs2, the controller is further configured as follows: when the first difference T1 is greater than or equal to the first set value S1, if the current speed Vt is greater than the initial target speed Vs1 and the difference between the two is greater than the second threshold, the outdoor fan is controlled to use the second speed V2 as the intermediate target speed Vs2; wherein the difference between the current speed Vt and the second speed V2 is the second threshold; if the difference between the two is less than the second threshold, the outdoor fan is controlled to use the initial target speed Vs1 as the intermediate target speed Vs2. When the first difference T1 is less than the second set value S2, the outdoor fan is controlled to use the first speed V1 as the intermediate target speed Vs2.

[0129] When determining the final target speed Vs3 of the outdoor fan, the controller is configured as follows: when the initial target speed Vs1 of the outdoor fan is less than the lower limit value Vmin, the outdoor fan is controlled to use the lower limit value Vmin as the final target speed Vs3; when the initial target speed Vs1 of the outdoor fan is greater than the upper limit value Vmax, the outdoor fan is controlled to use the upper limit value Vmax as the final target speed Vs3; when the initial target speed Vs1 of the outdoor fan is greater than or equal to the lower limit value Vmin and less than or equal to the upper limit value Vmax, the outdoor fan is controlled to use the initial target speed Vs1 as the final target speed Vs3.

[0130] The controller is further configured to control the outdoor fan to operate at the final target speed Vs3. At this point, the controller has completed the second control of the outdoor fan speed.

[0131] It should be noted that the current rotation speed Vt of the outdoor fan in the second control is the final target rotation speed Vs3 of the outdoor fan in the first control.

[0132] In practical applications, the controller usually controls the gear of the outdoor fan to control the speed of the outdoor fan. The outdoor fan usually includes multiple gears, and each gear corresponds to a corresponding speed. The controller controls the speed of the outdoor fan by controlling the gear of the outdoor fan, which is common knowledge in the art and will not be described in detail.

[0133] In the present application, the gears corresponding to the same coil temperature in different coil temperature change trends are not completely the same.

[0134] In this embodiment, the control principle of the outdoor fan is described in detail by taking the outdoor fan having 16 gears as an example.

[0135] The gear positions of the outdoor fan 16 are D1 to D16. When the detection value of the outdoor sensor is less than the first temperature value T1, the initial gear position of the outdoor fan is D5; when the detection value of the outdoor sensor is greater than or equal to the first temperature value T1 and less than the second temperature value T2, the initial gear position of the outdoor fan is D10; when the detection value of the outdoor sensor is greater than or equal to the second temperature value T2 and less than the third temperature value T3, the initial gear position of the outdoor fan is D15; when the detection value of the outdoor sensor is greater than or equal to the third temperature value T3, the initial gear position of the outdoor fan is D16.

[0136] like Fig.10 As shown, the upper limit gear position and the lower limit gear position of the outdoor fan are determined according to the outdoor ambient temperature, which will not be described in detail here.

[0137] In this embodiment, if the difference between the coil temperature at a later moment and the coil temperature at a previous moment is ≥1°C, the coil temperature change shows an upward trend; if the difference between the coil temperature at a later moment and the coil temperature at a previous moment is ≤-1°C, the coil temperature change shows a downward trend; otherwise, the coil temperature change shows a stable trend.

[0138] When the coil temperature changes in an upward trend, the corresponding relationship between the coil temperature and the outdoor fan gear is shown in Table 1. When the coil temperature changes in a downward trend, the corresponding relationship between the coil temperature and the outdoor fan gear is shown in Table 2.

[0139] Appendix 1: Correspondence between outer ring temperature and gear position during coil temperature rise

[0140]

[0141] Appendix 2: Correspondence between the outer ring temperature and the gear position during the coil temperature drop process

[0142]

[0143] like Fig.11 As shown, the detection value of the outdoor temperature sensor is obtained, and the initial gear position of the outdoor fan and the upper limit value and the lower limit value of the outdoor fan gear position are determined according to the detection value of the outdoor temperature sensor.

[0144] When the air conditioner starts cooling operation, after the outdoor fan runs at the initial gear for 3 minutes, the detection value of the coil temperature sensor is obtained, the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor is calculated as the first difference T1, and the change trend of the coil temperature is obtained;

[0145] If the first difference T1 is greater than or equal to the first set value S1, when the coil temperature changes in an upward trend, the initial target gear of the outdoor fan is determined according to the data in Table 1; when the coil temperature changes in a downward trend, the initial target gear of the outdoor fan is determined according to the data in Table 2; when the coil temperature changes in a stable trend, the initial gear of the outdoor fan is used as the initial target gear of the outdoor fan. It should be noted that when the initial target gear is lower than the initial gear, if the initial target gear is lowered by more than two gears compared to the initial gear, the outdoor fan is controlled to be at the gear after the initial gear is lowered by two gears as the intermediate target gear; if the initial target gear is lowered by no more than two gears compared to the initial gear, the outdoor fan is controlled to be at the initial target gear as the intermediate target gear.

[0146] If the first difference T1 is less than the second set value S2, the outdoor fan is controlled to use the gear position that is one gear lower than the current gear position as the intermediate target gear position.

[0147] If the first difference T1 is less than the first set value S1 and greater than or equal to the second set value S2, the outdoor fan is controlled to use the current gear as the intermediate target gear.

[0148] When the intermediate target gear of the outdoor fan is less than the lower limit value, the outdoor fan is controlled to operate with the lower limit value as the final gear; when the intermediate target gear of the outdoor fan is greater than the upper limit value, the outdoor fan is controlled to operate with the upper limit value as the final gear; when the intermediate target gear of the outdoor fan is greater than or equal to the lower limit value and less than or equal to the upper limit value, the outdoor fan is controlled to operate with the intermediate target gear as the final gear.

[0149] During the cooling operation of the air conditioner, the detection values ​​of the coil temperature sensor and the outdoor temperature sensor are re-obtained at regular intervals to re-judge the gear position of the outdoor fan.

[0150] When the above-mentioned air-conditioning outdoor unit is in cooling operation, it can achieve stable control of the outdoor fan speed under different outdoor ambient temperature conditions, thereby ensuring that the refrigerant pressure in the air-conditioning system meets safe operating conditions and does not fluctuate. At the same time, it can ensure that the refrigerant temperature in the outdoor heat exchanger has an ideal temperature difference with the outdoor ambient temperature, thereby ensuring the heat dissipation effect.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0152] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. An air conditioner outdoor unit, characterized in that: include: Condenser, used for exchanging heat with outdoor air; A compressor, which together with the condenser and the evaporator forms a refrigerant circulation loop, and the compressor is used to compress low-pressure refrigerant gas into high-pressure refrigerant gas and drive the refrigerant to flow in the refrigerant circulation loop; an outdoor fan, used to drive air to contact the condenser; A coil temperature sensor, used to detect the coil temperature of the condenser; Outdoor temperature sensor, used to detect outdoor ambient temperature; A controller is connected to the outdoor fan, the coil temperature sensor, and the outdoor temperature sensor respectively; the controller is configured as follows: Acquire the outdoor ambient temperature detected by the outdoor temperature sensor and the coil temperature detected by the coil temperature sensor, and calculate the difference between the coil temperature and the outdoor ambient temperature as a first difference; If the first difference is greater than or equal to a first set value, obtaining a target speed of the outdoor fan according to a preset correspondence between the coil temperature and the speed of the outdoor fan; If the first difference is less than the second set value, the first speed is used as the target speed of the outdoor fan; wherein the absolute value of the difference between the current speed of the outdoor fan and the first speed is a first threshold; If the first difference is smaller than the first set value and greater than or equal to the second set value, the current speed of the outdoor fan is used as the target speed of the outdoor fan.

2. The air conditioner outdoor unit according to claim 1, characterized in that: The controller is further configured to: determine the upper limit and lower limit of the outdoor fan speed according to the corresponding relationship between the preset outdoor ambient temperature and the outdoor fan speed; if the target speed of the outdoor fan is less than the lower limit, control the outdoor fan to operate at the lower limit as the actual speed; If the target speed of the outdoor fan is greater than the upper limit, the outdoor fan is controlled to operate at the upper limit as the actual speed; If the target rotation speed of the outdoor fan is greater than or equal to the lower limit value and less than or equal to the upper limit value, the outdoor fan is controlled to operate with the target rotation speed as the actual rotation speed.

3. The air conditioner outdoor unit according to claim 1 or 2, characterized in that: The controller is further configured to: when the first difference is greater than or equal to the first set value, if the difference between the current speed of the outdoor fan and the target speed is less than or equal to a second threshold, control the speed of the outdoor fan to operate with the target speed as the actual speed; If the difference between the current speed of the outdoor fan and the target speed is greater than a second threshold, the outdoor fan is controlled to finally operate at the second speed as the actual speed; wherein the difference between the current speed of the outdoor fan and the second speed is the second threshold.

4. The air conditioner outdoor unit according to claim 1, characterized in that: The controller is further configured to: when the first difference is greater than or equal to the first set value, if the target speed is less than the current speed of the outdoor fan, control the speed of the outdoor fan to change by at most a third threshold value.

5. The air conditioner outdoor unit according to claim 1, characterized in that: The controller is configured to: judge the changing trend of the coil temperature according to the detection value of the coil temperature sensor; when the first difference is greater than or equal to a first set value, determine the operating speed of the outdoor fan according to the changing trend of the coil temperature and the detection value of the coil temperature sensor.

6. The air conditioner outdoor unit according to claim 5, characterized in that: The controller is further configured to: if the coil temperature changes in a stable trend, control the outdoor fan to continue to operate at a current speed.

7. The air conditioner outdoor unit according to claim 5, characterized in that: In the case where the first difference is the same, the target rotation speed determined when at least part of the coil temperatures change in an upward trend is smaller than the target rotation speed determined when the coil temperatures change in a downward trend.

8. The air conditioner outdoor unit according to claim 1, characterized in that: The controller is configured to: determine the initial rotation speed of the outdoor fan according to the outdoor ambient temperature detected by the outdoor temperature sensor when the air conditioner outdoor unit starts cooling operation; After controlling the outdoor fan to run at the initial speed for a preset time, the detection value of the coil temperature sensor is obtained.

9. The air conditioner outdoor unit according to claim 8, characterized in that: The controller is configured as follows: among the initial speed of the outdoor fan, the upper limit value of the outdoor fan speed and the lower limit value of the outdoor fan speed determined based on the detection value of the same outdoor temperature sensor, the initial speed of the outdoor fan is greater than or equal to the upper limit value of the outdoor fan speed, and the initial speed of the outdoor fan is less than or equal to the lower limit value of the outdoor fan speed.

10. An air conditioner outdoor unit, characterized in that: include: Condenser, used for exchanging heat with outdoor air; A compressor, which together with the condenser and the evaporator forms a refrigerant circulation loop, and the compressor is used to compress low-pressure refrigerant gas into high-pressure refrigerant gas and drive the refrigerant to flow in the refrigerant circulation loop; An outdoor fan, used to drive air to contact the condenser; the outdoor fan is provided with a plurality of gears, each gear being provided with a corresponding rotation speed; Coil temperature sensor, used to detect coil temperature; Outdoor temperature sensor, used to detect outdoor ambient temperature; A controller is connected to the outdoor fan, the coil temperature sensor and the outdoor temperature sensor respectively; the controller is configured as follows: Acquire the detection value of the outdoor temperature sensor and the detection value of the coil temperature sensor, and calculate the difference between the detection value of the coil temperature sensor and the detection value of the outdoor temperature sensor as a first difference; Determining an initial target gear position of the outdoor fan according to a relationship between the first difference and a set value; The initial target gear position of the outdoor fan is corrected to obtain the final target gear position of the outdoor fan, and the outdoor fan is controlled to continue to operate at the final target gear position.

Images