Control method and device for air conditioning system and air conditioning system

Abstract

The invention relates to the technical field of refrigeration, and discloses a control method for an air conditioning system, which comprises the following steps: under the condition that the air conditioning system enters a double-evaporation-temperature refrigeration mode, determining a third target evaporation temperature of a first indoor heat exchanger, and determining a target evaporation temperature difference between the first indoor heat exchanger and a second indoor heat exchanger; the opening degree of a first throttling valve is adjusted so that the evaporation temperature of the first indoor heat exchanger can approach the third target evaporation temperature; and the opening degree of a second throttling valve is adjusted so that the evaporation temperature difference value of the first indoor heat exchanger and the second indoor heat exchanger can approach the target evaporation temperature difference value. The target evaporation temperature of the first indoor heat exchanger is set firstly, then the evaporation temperature of the second indoor heat exchanger is regulated and controlled based on the target evaporation temperature difference, gradient cooling of indoor air can be achieved, the comfortable experience of a user can be guaranteed, and the energy-saving effect of the air conditioning system is improved. The invention further discloses a control device for the air conditioning system and the air conditioning system.

Description

Technical Field

[0001] The present application relates to the field of refrigeration technology, for example, to a control method and device for an air-conditioning system and an air-conditioning system. Background Art

[0002] At present, the air conditioning system mainly includes components such as a compressor, a four-way valve, an indoor heat exchanger and an outdoor heat exchanger. When the air conditioner is operating in a cooling condition, the outdoor heat exchanger works as a condenser and the indoor heat exchanger works as an evaporator. However, since the indoor unit usually has only one heat exchanger, only one evaporation temperature can be achieved. In order to ensure the working effect in the cooling mode or dehumidification mode, it is often necessary to set the evaporation temperature lower. At this time, the pressure ratio of the compressor is relatively large, resulting in high energy consumption of the system, and the air supply temperature is too low, affecting the user's comfort experience. To this end, the relevant technology proposes to set two parallel heat exchangers in the indoor unit and control the evaporation temperatures of the two separately.

[0003] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0004] The operation mode of the air-conditioning system in the related technology is relatively simple, and it is difficult to reasonably set the two evaporation temperatures in combination with user or environmental needs. Therefore, there is still room for improvement in user comfort experience and system energy-saving effect.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0007] The embodiments of the present disclosure provide a control method, device and air-conditioning system for an air-conditioning system, which can achieve step-by-step cooling of indoor air, thereby ensuring the user's comfort experience and improving the energy-saving effect of the air-conditioning system.

[0008] In some embodiments, the air conditioning system includes: a compressor, including a medium-pressure cylinder and a low-pressure cylinder; a four-way valve, connected to the exhaust pipeline of the compressor and to the suction pipeline of the medium-pressure cylinder; a three-way valve, connected to the exhaust pipeline of the compressor and to the suction pipeline of the low-pressure cylinder; an outdoor heat exchanger, connected to the four-way valve; a first indoor heat exchanger, connected to the outdoor heat exchanger and to the four-way valve; a second indoor heat exchanger, connected in parallel with the first indoor heat exchanger and connected to the three-way valve; a first throttle valve, provided on the inlet pipeline of the first indoor heat exchanger in cooling mode; The second throttle valve is arranged on the inlet pipeline of the second indoor heat exchanger in the cooling mode; the method comprises: when the air-conditioning system enters the dual evaporation temperature cooling mode, determining the third target evaporation temperature of the first indoor heat exchanger and determining the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger; adjusting the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature; adjusting the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference.

[0009] In some embodiments, the device includes: a processor and a memory storing program instructions, and the processor is configured to execute the above-mentioned control method for the air-conditioning system when running the program instructions.

[0010] In some embodiments, the air-conditioning system includes: a compressor, including a medium-pressure cylinder and a low-pressure cylinder; a four-way valve, connected to the exhaust pipeline of the compressor and to the intake pipeline of the medium-pressure cylinder; a three-way valve, connected to the exhaust pipeline of the compressor and to the intake pipeline of the low-pressure cylinder; an outdoor heat exchanger, connected to the four-way valve; a first indoor heat exchanger, connected to the outdoor heat exchanger and to the four-way valve; a second indoor heat exchanger, connected in parallel with the first indoor heat exchanger and connected to the three-way valve; a first throttle valve, arranged on the inlet pipeline of the first indoor heat exchanger in cooling mode; a second throttle valve, arranged on the inlet pipeline of the second indoor heat exchanger in cooling mode; the above-mentioned control device for the air-conditioning system is electrically connected to the first throttle valve and the second throttle valve, respectively.

[0011] The control method, device and air conditioning system provided by the embodiments of the present disclosure can achieve the following technical effects:

[0012] In the disclosed embodiment, when the air conditioning system enters the dual evaporation temperature cooling mode, the third target evaporation temperature of the first indoor heat exchanger and the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are determined respectively. Then the disclosed embodiment adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the third target evaporation temperature. And adjust the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger gradually approaches the target evaporation temperature difference. Therefore, the disclosed embodiment first sets the target evaporation temperature of the first indoor heat exchanger, and then regulates the evaporation temperature of the second indoor heat exchanger based on the target evaporation temperature difference, so that the indoor air first passes through the first indoor heat exchanger for the first stage cooling, and then passes through the second indoor heat exchanger for the second stage cooling, so that the indoor air can be cooled step by step, which is conducive to reducing the irreversible loss of the heat transfer process. And the disclosed embodiment can adaptively increase the indoor air supply temperature, which is conducive to ensuring the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. As a result, the disclosed embodiment can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0013] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0015] Figure 1 is a structural schematic diagram of an air conditioning system provided by an embodiment of the present disclosure;

[0016] Figure 2 is a structural schematic diagram of another air conditioning system provided by an embodiment of the present disclosure;

[0017] Figure 3 is a schematic diagram of a control method for an air conditioning system provided by an embodiment of the present disclosure;

[0018] Figure 4 is a schematic diagram of another control method for an air conditioning system provided by an embodiment of the present disclosure;

[0019] Figure 5 is a schematic diagram of another control method for an air conditioning system provided by an embodiment of the present disclosure;

[0020] Figure 6 is a schematic diagram of another control method for an air conditioning system provided by an embodiment of the present disclosure;

[0021] Figure 7 is a schematic diagram of another control method for an air conditioning system provided by an embodiment of the present disclosure;

[0022] Figure 8 is a schematic diagram of a control device for an air conditioning system provided by an embodiment of the present disclosure;

[0023] Fig. 9 It is a schematic diagram of an air conditioner provided in an embodiment of the present disclosure.

[0024] Reference numerals:

[0025] 100: outdoor unit; 200: indoor unit; 10: compressor; 11: medium-pressure cylinder; 12: low-pressure cylinder; 21: four-way valve; 22: three-way valve; 30: outdoor heat exchanger; 41: first indoor heat exchanger; 42: second indoor heat exchanger; 51: first throttle valve; 52: second throttle valve; 53: third throttle valve; 61: outdoor fan; 62: indoor fan; 71: first gas-liquid separator; 72: second gas-liquid separator; 80: control device for air-conditioning system; 81: processor; 82: memory; 83: communication interface; 84: bus. DETAILED DESCRIPTION

[0026] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0027] The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0028] Unless otherwise stated, the term "plurality" means two or more.

[0029] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0030] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0031] The term "correspondence" may refer to an association relationship or a binding relationship. The correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

[0032] At present, the air conditioning system mainly includes components such as a compressor, a four-way valve, an indoor heat exchanger and an outdoor heat exchanger. When the air conditioner is operating in a cooling condition, the outdoor heat exchanger works as a condenser and the indoor heat exchanger works as an evaporator. However, since the indoor unit usually has only one heat exchanger, only one evaporation temperature can be achieved. In order to ensure the working effect in the cooling mode or dehumidification mode, it is often necessary to set the evaporation temperature lower. At this time, the pressure ratio of the compressor is relatively large, resulting in high energy consumption of the system, and the air supply temperature is too low, affecting the user's comfort experience. To this end, the relevant technology proposes to set two parallel heat exchangers in the indoor unit and control the evaporation temperatures of the two separately.

[0033] However, the operation mode of the air-conditioning system in the related technology is relatively simple, and it is difficult to reasonably set the two evaporation temperatures in combination with user or environmental needs. Therefore, there is still room for improvement in user comfort experience and system energy-saving effect.

[0034] Combination Figure 1-2 As shown, the embodiment of the present disclosure provides an air conditioning system, including: a compressor 10, a four-way valve 21, a three-way valve 22, an outdoor heat exchanger 30, a first indoor heat exchanger 41, a second indoor heat exchanger 42, a first throttle valve 51 and a second throttle valve 52. The compressor 10 includes a medium-pressure cylinder 11 and a low-pressure cylinder 12. The four-way valve 21 is connected to the exhaust pipeline of the compressor 10 and to the suction pipeline of the medium-pressure cylinder 11. The three-way valve 22 is connected to the exhaust pipeline of the compressor 10 and to the suction pipeline of the low-pressure cylinder 12. The outdoor heat exchanger 30 is connected to the four-way valve 21. The first indoor heat exchanger 41 is connected to the outdoor heat exchanger 30 and to the four-way valve 21. The second indoor heat exchanger 42 is connected in parallel with the first indoor heat exchanger 41 and is connected to the three-way valve 22. The first throttle valve 51 is provided in the inlet pipeline of the first indoor heat exchanger 41 in the cooling mode. The second throttle valve 52 is disposed on the inlet pipeline of the second indoor heat exchanger 42 in the cooling mode.

[0035] When the air conditioning system provided by the embodiment of the present disclosure is used and the dual evaporation temperature control is performed, the opening of the first throttle valve 51 is greater than the opening of the second throttle valve 52, and more refrigerant flows through the first indoor heat exchanger 41 to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder 11 of the compressor 10 through the four-way valve 21 to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger 42 to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder 12 of the compressor 10 through the three-way valve 22 to be compressed according to a larger pressure ratio. As a result, the embodiment of the present disclosure can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air conditioning system.

[0036] Optionally, the air conditioning system further includes a third throttle valve 53. The third throttle valve 53 is provided in the outlet pipe of the outdoor heat exchanger 30 in the cooling mode. When the dual evaporation temperature control is performed, the third throttle valve 53 is adjusted to the maximum opening, and at this time, the throttle control is realized only by the first throttle valve 51 and the second throttle valve 52, so as to avoid the suction pressure of the compressor 10 being too low, resulting in an increase in system energy consumption.

[0037] Optionally, the air conditioning system further includes an outdoor fan 61. The outdoor fan 61 is arranged relative to the outdoor heat exchanger 30. In this way, the embodiment of the present disclosure can enhance the heat exchange effect of the outdoor heat exchanger 30 through the outdoor fan 61, which is conducive to improving the working efficiency of the cooling mode and the dehumidification mode.

[0038] Optionally, the air conditioning system further includes an indoor fan 61. The indoor fan 61 is arranged relative to the second indoor heat exchanger 42. In this way, the embodiment of the present disclosure can enhance the heat exchange effect of the indoor heat exchanger through the indoor fan 61, which is conducive to improving the working efficiency of the cooling mode and the dehumidification mode. And the indoor fan 61 is arranged between the second indoor heat exchanger 42 and the air outlet of the indoor unit 200, so that the indoor air can be cooled step by step, which is conducive to reducing the irreversible loss of the heat transfer process.

[0039] Optionally, the air conditioning system further includes a first gas-liquid separator 71. The gas-liquid separator 71 is disposed on the air suction line of the medium pressure cylinder 11. Thus, by disposing the first gas-liquid separator 71 on the air suction line of the medium pressure cylinder 11, the embodiment of the present disclosure can prevent the liquid refrigerant from flowing back to the compressor 10 and causing liquid hammer, which is beneficial to ensure the normal operation of the air conditioning system.

[0040] Optionally, the air conditioning system further includes a second gas-liquid separator 72. The gas-liquid separator 72 is disposed on the air suction line of the low-pressure cylinder 12. In this way, by disposing the second gas-liquid separator 72 on the air suction line of the low-pressure cylinder 12, the embodiment of the present disclosure can prevent the liquid refrigerant from flowing back to the compressor 10 to cause liquid hammer, which is conducive to ensuring the normal operation of the air conditioning system.

[0041] Optionally, the volume of the medium-pressure cylinder 11 is greater than the volume of the low-pressure cylinder 12. The volume ratio of the medium-pressure cylinder 11 to the low-pressure cylinder 12 can be reasonably set according to the ratio of the sensible heat load to the latent heat load. In this way, since more medium-pressure gaseous refrigerant is compressed in the medium-pressure cylinder 11 with a small pressure ratio, the embodiment of the present disclosure can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0042] Optionally, the heat exchange area of ​​the first indoor heat exchanger 41 is larger than the heat exchange area of ​​the second indoor heat exchanger 42. In this way, since the heat exchange area of ​​the first indoor heat exchanger 41 with a relatively high evaporation temperature is larger, the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is conducive to better ensuring the user's comfort experience.

[0043] Optionally, the air conditioning system includes an outdoor unit 100 and an indoor unit 200. The outdoor unit 100 includes a compressor 10, a four-way valve 21, a three-way valve 22, and an outdoor heat exchanger 30. The indoor unit 200 includes a first indoor heat exchanger 41, a second indoor heat exchanger 42, a first throttle valve 51, and a second throttle valve 52. In this way, the embodiment of the present disclosure enables the refrigerant to exchange heat in the outdoor unit 100 and the indoor unit 200, respectively, and the corresponding operation mode is executed to ensure the comfort experience of indoor users.

[0044] Optionally, there are multiple indoor units 200, and the multiple indoor units 200 are arranged in parallel. In this way, the embodiment of the present disclosure constitutes a multi-split air conditioning system, which can serve multiple indoor spaces at the same time, which is conducive to ensuring the comfort experience of multiple users.

[0045] Optionally, the air conditioning system further includes a control device 80 for the air conditioning system. The control device 80 for the air conditioning system is electrically connected to the first throttle valve 51 and the second throttle valve 52, respectively. In this way, the embodiment of the present disclosure can execute a corresponding control method through the control device 80 to more reasonably operate the cooling mode or the dehumidification mode.

[0046] Combination Figure 3 As shown, the embodiment of the present disclosure provides a control method for an air conditioning system, comprising:

[0047] S301, when the air-conditioning system enters the dual evaporating temperature cooling mode, the processor determines a third target evaporating temperature of the first indoor heat exchanger, and determines a target evaporating temperature difference between the first indoor heat exchanger and the second indoor heat exchanger.

[0048] S302: The processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature.

[0049] S303: The processor adjusts the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference.

[0050] According to the control method for an air conditioning system provided by the embodiment of the present disclosure, when the air conditioning system enters the dual evaporation temperature cooling mode, the third target evaporation temperature of the first indoor heat exchanger and the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are determined respectively. Then, the embodiment of the present disclosure adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the third target evaporation temperature. And adjust the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger gradually approaches the target evaporation temperature difference. Therefore, the embodiment of the present disclosure first sets the target evaporation temperature of the first indoor heat exchanger, and then adjusts the evaporation temperature of the second indoor heat exchanger based on the target evaporation temperature difference, so that the indoor air first passes through the first indoor heat exchanger for the first stage cooling, and then passes through the second indoor heat exchanger for the second stage cooling, so that the indoor air can be cooled step by step, which is conducive to reducing the irreversible loss of the heat transfer process. And the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is conducive to ensuring the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. As a result, the disclosed embodiment can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0051] Optionally, the target evaporation temperature difference has a value range of [5°C, 10°C]. Preferably, the target evaporation temperature difference is 8°C, which can achieve step-by-step cooling of the indoor air and is beneficial to reducing the irreversible loss of the heat transfer process. The target evaporation temperature difference can also be adjusted according to the actual needs of the user, and can also be set to any other reasonable value such as 6°C or 9°C.

[0052] Optionally, the processor determines the third target evaporating temperature of the first indoor heat exchanger, including: the processor determines the target cooling temperature difference according to the difference between the indoor ambient temperature and the target setting temperature; the processor calculates the difference between the target setting temperature and the target cooling temperature difference to obtain the third target evaporating temperature of the first indoor heat exchanger. In this way, the embodiment of the present disclosure can reasonably set the target cooling temperature difference in combination with the difference between the current indoor ambient temperature and the target setting temperature to determine the extent to which the third target evaporating temperature is less than the target setting temperature, thereby controlling the actual cooling efficiency of the first indoor heat exchanger so that it can accurately match the current cooling process, which is conducive to taking into account both the cooling effect and the energy-saving effect of the air-conditioning system.

[0053] Optionally, the target cooling temperature difference is positively correlated with the difference between the indoor ambient temperature and the target set temperature. Specifically, in some embodiments, when the difference between the indoor ambient temperature and the target set temperature is greater than or equal to 6°C, the target cooling temperature difference is determined to be 5°C; or, when the difference between the indoor ambient temperature and the target set temperature is less than 6°C, the target cooling temperature difference is determined to be 3°C. The relevant values ​​can be adaptively adjusted according to the actual needs of the user, or can be set to any other values ​​that meet the above positive correlation.

[0054] In this way, when the indoor ambient temperature is much higher than the target setting temperature, the demand for cooling capacity is relatively large. The disclosed embodiment can set a relatively large target cooling temperature difference to determine a relatively lower third target evaporation temperature, so that the cooling efficiency of the first indoor heat exchanger can be appropriately improved to match the current larger cooling capacity demand. In this way, the cooling effect of the air-conditioning system can be reasonably improved, which is conducive to better ensuring the user's comfort experience. On the contrary, when the indoor ambient temperature is slightly higher than the target setting temperature, the demand for cooling capacity is relatively small. The disclosed embodiment can set a relatively large target cooling temperature difference to determine a relatively higher third target evaporation temperature, so that the cooling efficiency of the first indoor heat exchanger can be appropriately reduced to match the current smaller cooling capacity demand. While ensuring the cooling effect, the indoor air supply temperature can also be increased, which is conducive to ensuring the user's comfort experience, and can further reduce the system energy consumption, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0055] Optionally, the processor determines the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, including: the processor determines the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger according to the indoor environmental humidity. In this way, the disclosed embodiment can reasonably set the target evaporation temperature difference in combination with the current indoor environmental humidity to determine the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, thereby controlling the actual dehumidification amount of the second indoor heat exchanger so that it can accurately match the current indoor humidity condition, which is conducive to taking into account both the cooling effect and the dehumidification effect of the air-conditioning system.

[0056] Optionally, the target evaporation temperature difference is positively correlated with the indoor ambient humidity. Specifically, in some embodiments, when the indoor ambient humidity is less than 40%, the target evaporation temperature difference is determined to be 7°C; or, when the indoor ambient humidity is greater than or equal to 40% and less than 60%, the target evaporation temperature difference is determined to be 8°C; or, when the indoor ambient humidity is greater than or equal to 60%, the target evaporation temperature difference is determined to be 9°C. The relevant values ​​can be adaptively adjusted according to the actual needs of the user, or can be set to any other values ​​that meet the above positive correlation.

[0057] In this way, when the indoor environmental humidity is too low, the dehumidification amount in the dual evaporation temperature cooling mode should be reasonably controlled. The disclosed embodiment can set a smaller target evaporation temperature difference so that the evaporation temperature of the second indoor heat exchanger is relatively higher, thereby being able to appropriately reduce the dehumidification amount of the second indoor heat exchanger to avoid indoor air drying. At the same time, the indoor air supply temperature can also be increased, which is conducive to ensuring the user's comfort experience, and can further reduce the system energy consumption, which is conducive to improving the energy-saving effect of the air-conditioning system. On the contrary, when the indoor environmental humidity is too high, a certain amount of dehumidification is required while running the dual evaporation temperature cooling mode. The disclosed embodiment can set a larger target evaporation temperature difference so that the evaporation temperature of the second indoor heat exchanger is relatively lower, thereby being able to increase the dehumidification amount of the second indoor heat exchanger. In this way, the cooling effect and the dehumidification effect of the air-conditioning system can be taken into account, which is conducive to better ensuring the user's comfort experience.

[0058] Optionally, the processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature, including: when the evaporation temperature of the first indoor heat exchanger is greater than the third target evaporation temperature, the processor reduces the opening of the first throttle valve; or, when the evaporation temperature of the first indoor heat exchanger is less than the third target evaporation temperature, the processor increases the opening of the first throttle valve. In this way, when the evaporation temperature of the first indoor heat exchanger is greater than the third target evaporation temperature, it indicates that the evaporation temperature of the first indoor heat exchanger is too high at this time, and the cooling effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure reduces the opening of the first throttle valve, so as to reduce the refrigerant flow through the first indoor heat exchanger, so as to appropriately reduce the evaporation pressure of the first indoor heat exchanger, and then the evaporation temperature of the first indoor heat exchanger can be gradually reduced and approach the third target evaporation temperature. When the evaporation temperature of the first indoor heat exchanger is less than the third target evaporation temperature, it indicates that the evaporation temperature of the first indoor heat exchanger is too low at this time, and the energy-saving effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure increases the opening of the first throttle valve, thereby increasing the refrigerant flow rate flowing through the first indoor heat exchanger, so as to appropriately increase the evaporation pressure of the first indoor heat exchanger, and then the evaporation temperature of the first indoor heat exchanger can be gradually increased and approach the third target evaporation temperature. Therefore, the embodiment of the present disclosure can achieve accurate regulation of the evaporation temperature corresponding to the first indoor heat exchanger, so that it can gradually stabilize near the third target evaporation temperature that is less than the target setting temperature.

[0059] Optionally, the processor may use a PID (Proportional Integral Derivative) algorithm to increase or decrease the opening of the first throttle valve, and the corresponding PID adjustment value may be a fixed number of steps or a fixed ratio. Optionally, the PID adjustment value is positively correlated with the absolute value of the third real-time temperature difference between the evaporation temperature of the first indoor heat exchanger and the third target evaporation temperature. In this way, the embodiment of the present disclosure can achieve precise adjustment of the evaporation temperature corresponding to the first indoor heat exchanger, so that it can gradually stabilize near the third target evaporation temperature that is less than the target set temperature.

[0060] Optionally, the processor adjusts the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference, including: when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, the processor increases the opening of the second throttle valve; or, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, the processor reduces the opening of the second throttle valve. In this way, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is low at this time, and the energy-saving effect of the air-conditioning system is poor. Therefore, the embodiment of the present disclosure increases the opening of the second throttle valve, so that the refrigerant flow rate flowing through the second indoor heat exchanger can be increased to appropriately increase the evaporation pressure of the second indoor heat exchanger, and then the evaporation temperature of the second indoor heat exchanger can be gradually increased, so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger can be reduced and approached to the target evaporation temperature difference. When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is too high and the cooling effect of the air-conditioning system is poor. Therefore, the embodiment of the present disclosure reduces the opening of the second throttle valve, thereby reducing the refrigerant flow through the second indoor heat exchanger to appropriately reduce the evaporation pressure of the second indoor heat exchanger, and then the evaporation temperature of the second indoor heat exchanger can be gradually reduced, thereby increasing the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger and making it approach the target evaporation temperature difference. Therefore, the embodiment of the present disclosure can achieve precise adjustment of the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, so that it can gradually stabilize near the target evaporation temperature difference corresponding to the optimal performance condition.

[0061] Optionally, the processor may use a PID algorithm to increase or decrease the opening of the second throttle valve, and the corresponding PID adjustment value may be a fixed number of steps or a fixed ratio. Optionally, the PID adjustment value and the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are positively correlated with the absolute value of the fourth real-time temperature difference of the target evaporation temperature difference. In this way, the embodiment of the present disclosure can achieve precise adjustment of the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, so that it can gradually stabilize near the target evaporation temperature difference corresponding to the optimal performance condition.

[0062] Optionally, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, it also includes: when the evaporation temperature of the second indoor heat exchanger is greater than the first protection temperature, the processor maintains the opening of the second throttle valve unchanged and reduces the opening of the first throttle valve. In this way, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is low or the evaporation temperature of the first indoor heat exchanger is high. Therefore, the embodiment of the present disclosure can selectively increase the opening of the second throttle valve and / or reduce the opening of the first throttle valve to reduce the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger and make it close to the target evaporation temperature difference. Further, when it is detected that the evaporation temperature of the second indoor heat exchanger is greater than the first protection temperature, it indicates that the current evaporation temperature of the second indoor heat exchanger is too high, and the corresponding evaporation temperature of the first indoor heat exchanger is also high. At this time, the refrigeration efficiency of the air-conditioning system is low, and the actual refrigeration effect is poor. Therefore, the embodiment of the present disclosure does not change the opening of the second throttle valve, so as to avoid the evaporation temperature of the second indoor heat exchanger from further increasing so as to seriously affect the cooling effect of the air-conditioning system. Instead, the opening of the first throttle valve is appropriately reduced to reduce the refrigerant flow through the first indoor heat exchanger, so that the evaporation temperature of the first indoor heat exchanger can be gradually reduced, which is beneficial to improving the cooling efficiency of the air-conditioning system. Therefore, the embodiment of the present disclosure reasonably adjusts the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, so that it can gradually stabilize near the target evaporation temperature difference corresponding to the optimal performance condition, and at the same time can also improve the cooling effect of the air-conditioning system, which is beneficial to ensuring the user's comfort experience.

[0063] Optionally, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, it also includes: when the evaporation temperature of the second indoor heat exchanger is less than the second protection temperature, the processor maintains the opening of the second throttle valve unchanged and increases the opening of the first throttle valve. In this way, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is too high or the evaporation temperature of the first indoor heat exchanger is too low. Therefore, the embodiment of the present disclosure can selectively reduce the opening of the second throttle valve and / or increase the opening of the first throttle valve to increase the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger and make it approach the target evaporation temperature difference. Further, when it is detected that the evaporation temperature of the second indoor heat exchanger is less than the second protection temperature, it indicates that the current evaporation temperature of the second indoor heat exchanger is too low. At this time, the air-conditioning system may trigger the anti-freeze protection mode, thereby affecting the normal operation of the dual evaporation temperature refrigeration mode. Therefore, the embodiment of the present disclosure does not change the opening of the second throttle valve, so as to avoid the evaporation temperature of the second indoor heat exchanger from further decreasing to trigger the anti-freeze protection mode. Instead, the opening of the first throttle valve is appropriately increased to increase the refrigerant flow through the first indoor heat exchanger, so that the evaporation temperature of the first indoor heat exchanger can be gradually increased, which is beneficial to improving the energy-saving effect of the air-conditioning system. Therefore, the embodiment of the present disclosure reasonably adjusts the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, so that it can gradually stabilize near the target evaporation temperature difference corresponding to the optimal performance condition, and at the same time can also improve the energy-saving effect of the air-conditioning system, which is beneficial to ensuring the user's comfortable experience.

[0064] Combination Figure 4 As shown, the embodiment of the present disclosure provides another control method for an air conditioning system, comprising:

[0065] S401, when the air-conditioning system enters the dual evaporating temperature cooling mode, the processor determines a third target evaporating temperature of the first indoor heat exchanger, and determines a target evaporating temperature difference between the first indoor heat exchanger and the second indoor heat exchanger.

[0066] S402: The processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature.

[0067] S403: When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, the processor increases the opening of the second throttle valve.

[0068] S404: When the evaporation temperature of the second indoor heat exchanger is greater than the first protection temperature, the processor maintains the opening of the second throttle valve unchanged and reduces the opening of the first throttle valve.

[0069] S405: When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, the processor reduces the opening of the second throttle valve.

[0070] S406: When the evaporation temperature of the second indoor heat exchanger is lower than the second protection temperature, the processor maintains the opening of the second throttle valve unchanged and increases the opening of the first throttle valve.

[0071] Using the control method for an air conditioning system provided by the embodiment of the present disclosure, when the air conditioning system enters the dual evaporation temperature cooling mode, the third target evaporation temperature of the first indoor heat exchanger and the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are determined respectively. Then the embodiment of the present disclosure adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the third target evaporation temperature. And adjust the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger gradually approaches the target evaporation temperature difference. Specifically, when the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is low or the evaporation temperature of the first indoor heat exchanger is high. Therefore, the embodiment of the present disclosure can preferentially increase the opening of the second throttle valve to reduce the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger and make it approach the target evaporation temperature difference. Further, when it is detected that the evaporation temperature of the second indoor heat exchanger is greater than the first protection temperature, it indicates that the current evaporation temperature of the second indoor heat exchanger is too high, and the corresponding evaporation temperature of the first indoor heat exchanger is also high. At this time, the refrigeration efficiency of the air-conditioning system is low, and the actual refrigeration effect is poor. Therefore, the embodiment of the present disclosure does not change the opening of the second throttle valve, so as to avoid the evaporation temperature of the second indoor heat exchanger from further increasing so as to seriously affect the refrigeration effect of the air-conditioning system. Instead, the opening of the first throttle valve is appropriately reduced to reduce the refrigerant flow through the first indoor heat exchanger, so that the evaporation temperature of the first indoor heat exchanger can be gradually reduced, which is conducive to improving the refrigeration efficiency of the air-conditioning system. When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, it indicates that the evaporation temperature of the second indoor heat exchanger is high or the evaporation temperature of the first indoor heat exchanger is low. Therefore, the embodiment of the present disclosure can preferentially reduce the opening of the second throttle valve to increase the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger and make it close to the target evaporation temperature difference. Furthermore, when it is detected that the evaporation temperature of the second indoor heat exchanger is lower than the second protection temperature, it indicates that the current evaporation temperature of the second indoor heat exchanger is too low. At this time, the air-conditioning system may trigger the anti-freeze protection mode, thereby affecting the normal operation of the dual evaporation temperature refrigeration mode. Therefore, the embodiment of the present disclosure does not change the opening of the second throttle valve, so as to avoid the evaporation temperature of the second indoor heat exchanger from further decreasing to trigger the anti-freeze protection mode. Instead, the opening of the first throttle valve is appropriately increased to increase the refrigerant flow through the first indoor heat exchanger, so that the evaporation temperature of the first indoor heat exchanger can be gradually increased, which is beneficial to improving the energy-saving effect of the air-conditioning system. Therefore, the embodiment of the present disclosure reasonably adjusts the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, so that it can gradually stabilize near the target evaporation temperature difference corresponding to the optimal performance condition, while also taking into account the refrigeration effect and energy-saving effect of the air-conditioning system, which is beneficial to ensuring the user's comfortable experience.Therefore, the embodiment of the present disclosure sets the target evaporation temperature of the first indoor heat exchanger first, and then adjusts the evaporation temperature of the second indoor heat exchanger based on the target evaporation temperature difference, so that the indoor air first passes through the first indoor heat exchanger for the first stage cooling, and then passes through the second indoor heat exchanger for the second stage cooling, so that the indoor air can be cooled step by step, which is beneficial to reducing the irreversible loss of the heat transfer process. And the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is beneficial to ensure the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. Therefore, the embodiment of the present disclosure can further reduce the energy consumption of the system, which is beneficial to improving the energy-saving effect of the air-conditioning system.

[0072] Optionally, the first protection temperature can be set according to the indoor environmental conditions. Preferably, the first protection temperature can be set to the current dew point temperature to avoid the actual cooling efficiency being too low. The first protection temperature can also be adjusted according to the actual needs of the user, and can also be set to any other reasonable value.

[0073] Optionally, the second protection temperature can be set according to the indoor environmental conditions. Preferably, the second protection temperature can be set to 8°C to avoid triggering the anti-freeze protection mode. The second protection temperature can also be adjusted according to the actual needs of the user, and can also be set to any other reasonable value.

[0074] Combination Figure 5 As shown, the embodiment of the present disclosure provides another control method for an air conditioning system, comprising:

[0075] S501, when the air-conditioning system enters the dual evaporating temperature cooling mode, the processor determines a third target evaporating temperature of the first indoor heat exchanger, and determines a target evaporating temperature difference between the first indoor heat exchanger and the second indoor heat exchanger.

[0076] S502: The processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature.

[0077] S503: The processor adjusts the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference.

[0078] S504: The processor obtains the suction pressure of the medium-pressure cylinder and obtains the suction pressure of the low-pressure cylinder.

[0079] S505: When the difference between the suction pressure of the medium-pressure cylinder and the suction pressure of the low-pressure cylinder is less than a preset pressure difference, the processor increases the difference between the openings of the first throttle valve and the second throttle valve.

[0080] According to the control method for an air conditioning system provided by the embodiment of the present disclosure, when the air conditioning system enters the dual evaporation temperature cooling mode, the third target evaporation temperature of the first indoor heat exchanger and the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are determined respectively. Then, the embodiment of the present disclosure adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the third target evaporation temperature. And adjust the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger gradually approaches the target evaporation temperature difference. Therefore, the embodiment of the present disclosure first sets the target evaporation temperature of the first indoor heat exchanger, and then adjusts the evaporation temperature of the second indoor heat exchanger based on the target evaporation temperature difference, so that the indoor air first passes through the first indoor heat exchanger for the first stage cooling, and then passes through the second indoor heat exchanger for the second stage cooling, so that the indoor air can be cooled step by step, which is conducive to reducing the irreversible loss of the heat transfer process. And the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is conducive to ensuring the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. As a result, the disclosed embodiment can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system. In addition, the disclosed embodiment also monitors the suction pressure of the medium-pressure cylinder and the suction pressure of the low-pressure cylinder respectively, and appropriately increases the opening difference between the first throttle valve and the second throttle valve when the pressure difference between the two is less than the preset pressure difference, so as to increase the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger, and avoid the air-conditioning system from switching from a dual evaporation temperature refrigeration mode to a single evaporation temperature refrigeration mode, which affects the user's comfort experience and the energy-saving effect of the air-conditioning system.

[0081] Optionally, the preset pressure difference can be set according to the indoor environmental conditions. Preferably, the preset pressure difference can be set to 0.05MPa to ensure the stable operation of the dual evaporation temperature cooling mode. The preset pressure difference can also be adjusted according to the actual needs of the user, and can also be set to any other reasonable value such as 0.01MPa or 0.10MPa.

[0082] Optionally, the processor increases the opening difference between the first throttle valve and the second throttle valve, including: the processor increases the opening of the first throttle valve; and / or, the processor reduces the opening of the second throttle valve. In this way, when the suction pressure of the intermediate pressure cylinder and the suction pressure of the low pressure cylinder are less than the preset pressure difference, it indicates that the refrigerant flowing out of the first indoor heat exchanger and the refrigerant pressure flowing out of the second indoor heat exchanger are relatively close. At this time, the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is small, and the air conditioning system is about to switch from the dual evaporation temperature refrigeration mode to the single evaporation temperature refrigeration mode, which will affect the user's comfort experience and the energy-saving effect of the air conditioning system. Therefore, the embodiment of the present disclosure adaptively increases the opening of the first throttle valve, and / or reduces the opening of the second throttle valve, so as to expand the opening difference between the first throttle valve and the second throttle valve, so as to ensure that the first indoor heat exchanger and the second indoor heat exchanger can form a suitable evaporation temperature difference, which is conducive to taking into account the refrigeration effect and energy-saving effect of the air conditioning system.

[0083] Optionally, the processor may use a PID algorithm to increase or decrease the opening of the first throttle valve and / or the second throttle valve, and the corresponding PID adjustment value may be a fixed number of steps or a fixed ratio. Optionally, the PID adjustment value is negatively correlated with the difference in opening between the first throttle valve and the second throttle valve. In this way, the embodiment of the present disclosure can reasonably increase the difference in opening between the first throttle valve and the second throttle valve when the suction pressure of the medium-pressure cylinder and the low-pressure cylinder are relatively close, thereby ensuring the stable operation of the dual evaporation temperature refrigeration mode.

[0084] Combination Figure 6 As shown, the embodiment of the present disclosure provides another control method for an air conditioning system, comprising:

[0085] S601, the processor obtains the difference between the indoor ambient temperature and the target setting temperature.

[0086] S602: When the difference between the indoor ambient temperature and the target set temperature is greater than or equal to a first preset temperature difference, the processor controls the air conditioning system to enter a fast cooling mode. Or,

[0087] S603: When the difference between the indoor ambient temperature and the target set temperature is less than the first preset temperature difference and greater than or equal to the second preset temperature difference, the processor controls the air conditioning system to enter the dual evaporation temperature cooling mode. Or,

[0088] S604, when the difference between the indoor ambient temperature and the target set temperature is less than the second preset temperature difference, the processor controls the air conditioning system to enter a cool but not cold mode.

[0089] S605, when the air-conditioning system enters the dual evaporating temperature cooling mode, the processor determines a third target evaporating temperature of the first indoor heat exchanger, and determines a target evaporating temperature difference between the first indoor heat exchanger and the second indoor heat exchanger.

[0090] S606: The processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature.

[0091] S607: The processor adjusts the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference.

[0092] According to the control method for an air conditioning system provided by the embodiment of the present disclosure, when the air conditioning system receives a cooling instruction sent by a user, the difference between the indoor ambient temperature and the target setting temperature is obtained to automatically determine which cooling mode to enter. When the difference between the indoor ambient temperature and the target setting temperature is greater than or equal to the first preset temperature difference, the indoor ambient temperature is much greater than the target setting temperature. At this time, the cooling demand is more significant. The air conditioning system can be controlled to automatically enter the fast cooling mode to appropriately improve the cooling efficiency of the air conditioning system. When the difference between the indoor ambient temperature and the target setting temperature is less than the first preset temperature difference and greater than or equal to the second preset temperature difference, the indoor ambient temperature is slightly greater than the target setting temperature. At this time, the cooling demand is relatively general. The air conditioning system can be controlled to automatically enter the dual evaporation temperature dehumidification mode to take into account both the cooling efficiency and the energy saving effect. When the difference between the indoor ambient temperature and the target setting temperature is less than the second preset temperature difference, the indoor ambient temperature is close to the target setting temperature. At this time, the air supply temperature should be avoided as much as possible. The air conditioning system can be controlled to automatically enter the cool but not cold mode to take into account both the user comfort experience and the system energy saving effect. Among them, when the air conditioning system enters the dual evaporation temperature cooling mode, the third target evaporation temperature of the first indoor heat exchanger and the target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger are determined respectively. Then the embodiment of the present disclosure adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the third target evaporation temperature. And adjust the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger gradually approaches the target evaporation temperature difference. Therefore, the embodiment of the present disclosure first sets the target evaporation temperature of the first indoor heat exchanger, and then adjusts the evaporation temperature of the second indoor heat exchanger based on the target evaporation temperature difference, so that the indoor air first passes through the first indoor heat exchanger for the first stage of cooling, and then passes through the second indoor heat exchanger for the second stage of cooling, so that the indoor air can be cooled step by step, which is conducive to reducing the irreversible loss of the heat transfer process. And the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is conducive to ensuring the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. As a result, the disclosed embodiment can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0093] Optionally, the first preset temperature difference and the second preset temperature difference can be set according to actual needs of the user. Preferably, the first preset temperature difference can be set to 12°C, and the second preset temperature difference can be set to 3°C.

[0094] Optionally, the control method for the air conditioning system further includes: when the air conditioning system enters the rapid cooling mode, the processor determines the fifth target evaporation temperature of the first indoor heat exchanger and the second indoor heat exchanger; the processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the fifth target evaporation temperature; the processor adjusts the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger approaches the fifth target evaporation temperature. Wherein, the fifth target evaporation temperature is less than the third target evaporation temperature. In this way, when the difference between the indoor ambient temperature and the target setting temperature is greater than or equal to the first preset temperature difference, the indoor ambient temperature is much greater than the target setting temperature, and the cooling demand is more significant at this time, and the air conditioning system can be controlled to automatically enter the rapid cooling mode to appropriately improve the cooling efficiency of the air conditioning system. By determining the fifth target evaporation temperature that is the same for the first indoor heat exchanger and the second indoor heat exchanger in the rapid cooling mode, the embodiment of the present disclosure can control the air conditioning system to perform the single evaporation temperature cooling mode. And by adjusting the opening of the first throttle valve and the second throttle valve respectively, the evaporation temperatures of the first indoor heat exchanger and the second indoor heat exchanger are close to the fifth target evaporation temperature. Therefore, by setting a relatively low fifth target evaporating temperature, the disclosed embodiment can further improve the cooling efficiency of the air-conditioning system to match the current high indoor temperature conditions, which is conducive to better ensuring the user's comfort experience.

[0095] Optionally, the control method for the air conditioning system further includes: when the air conditioning system enters the cool but not cold mode, the processor determines the sixth target evaporation temperature of the first indoor heat exchanger and the second indoor heat exchanger; the processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the sixth target evaporation temperature; the processor adjusts the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger approaches the sixth target evaporation temperature. Wherein, the sixth target evaporation temperature is greater than the third target evaporation temperature. In this way, when the difference between the indoor ambient temperature and the target setting temperature is less than the second preset temperature difference, the indoor ambient temperature is close to the target setting temperature. At this time, the air supply temperature should be avoided as much as possible, and the air conditioning system can be controlled to automatically enter the cool but not cold mode to take into account the user's comfort experience and the system energy saving effect. By determining the sixth target evaporation temperature that the first indoor heat exchanger and the second indoor heat exchanger are the same in the cool but not cold mode, the embodiment of the present disclosure can control the air conditioning system to perform a single evaporation temperature cooling mode. And by adjusting the opening of the first throttle valve and the second throttle valve respectively, the evaporation temperatures of the first indoor heat exchanger and the second indoor heat exchanger are approached to the sixth target evaporation temperature. Therefore, by setting a relatively high sixth target evaporation temperature, the disclosed embodiment can adaptively increase the indoor air supply temperature, which is beneficial to ensuring the user's comfort experience, and can reduce system energy consumption, which is beneficial to improving the energy-saving effect of the air-conditioning system.

[0096] Combination Figure 7As shown, the embodiment of the present disclosure provides another control method for an air conditioning system, comprising:

[0097] S701, when the air conditioning system enters the dual evaporating temperature dehumidification mode, the processor determines a first target evaporating temperature of the first indoor heat exchanger and determines a second target evaporating temperature of the second indoor heat exchanger.

[0098] The first target evaporation temperature is greater than the dew point temperature, and the second target evaporation temperature is less than the dew point temperature.

[0099] S702: The processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the first target evaporation temperature.

[0100] S703: The processor adjusts the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger approaches the second target evaporation temperature.

[0101] Using the control method for an air conditioning system provided by the embodiment of the present disclosure, when the air conditioning system enters the dual evaporation temperature dehumidification mode, the first target evaporation temperature of the first indoor heat exchanger greater than the dew point temperature and the second target evaporation temperature of the second indoor heat exchanger less than the dew point temperature are determined respectively. Then the embodiment of the present disclosure adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger gradually approaches the first target evaporation temperature, so that the sensible heat load can be removed by the first indoor heat exchanger. And adjust the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger gradually approaches the second target evaporation temperature, so that the latent heat load can be removed by the second indoor heat exchanger. Therefore, the embodiment of the present disclosure sets the target evaporation temperatures corresponding to the first indoor heat exchanger and the second indoor heat exchanger respectively, so that the indoor air is first cooled by the first indoor heat exchanger, and then dehumidified by the second indoor heat exchanger, so that the indoor temperature and humidity can be controlled relatively independently. And the embodiment of the present disclosure can adaptively increase the indoor air supply temperature, which is conducive to ensuring the user's comfortable experience. At the same time, since the evaporation temperature of the first indoor heat exchanger is greater than the evaporation temperature of the second indoor heat exchanger, the opening of the first throttle valve is usually greater than the opening of the second throttle valve, and more refrigerant flows through the first indoor heat exchanger to form a medium-pressure gaseous refrigerant, and returns to the medium-pressure cylinder of the compressor through the four-way valve to be compressed according to a smaller pressure ratio. A small amount of refrigerant flows through the second indoor heat exchanger to form a low-pressure gaseous refrigerant, and returns to the low-pressure cylinder of the compressor through the three-way valve to be compressed according to a larger pressure ratio. As a result, the disclosed embodiment can further reduce the energy consumption of the system, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0102] Optionally, the processor determines the second target evaporation temperature of the second indoor heat exchanger, including: the processor determines the current dew point temperature according to the indoor ambient temperature and the indoor ambient humidity; the processor determines the second dehumidification temperature difference according to the indoor ambient humidity; the processor calculates the difference between the current dew point temperature and the second dehumidification temperature difference to obtain the second target evaporation temperature of the second indoor heat exchanger. In this way, the embodiment of the present disclosure can reasonably set the second dehumidification temperature difference in combination with the current indoor ambient humidity to determine the extent to which the second target evaporation temperature is less than the dew point temperature, thereby controlling the actual dehumidification efficiency of the second indoor heat exchanger so that it can accurately match the current indoor humidity condition, which is conducive to taking into account both the dehumidification effect and the energy-saving effect of the air-conditioning system.

[0103] Optionally, the second dehumidification temperature difference is positively correlated with the indoor ambient humidity. Specifically, in some embodiments, when the indoor ambient humidity is greater than or equal to 60% and less than 80%, the second dehumidification temperature difference is determined to be 5°C; or, when the indoor ambient humidity is greater than or equal to 80% and less than 90%, the second dehumidification temperature difference is determined to be 7°C; or, when the indoor ambient humidity is greater than or equal to 90%, the second dehumidification temperature difference is determined to be 10°C. The relevant values ​​can be adaptively adjusted according to the actual needs of the user, or can be set to any other values ​​that meet the above positive correlation.

[0104] In this way, when the indoor environmental humidity is low, the demand for dehumidification is low. The disclosed embodiment can set a relatively small second dehumidification temperature difference to determine a second target evaporation temperature that is slightly lower than the current dew point temperature, so that the dehumidification efficiency of the second indoor heat exchanger can be appropriately reduced to match the current smaller dehumidification demand. While ensuring the dehumidification effect, the indoor air supply temperature can also be increased, which is conducive to ensuring the user's comfort experience, and can further reduce the system energy consumption, which is conducive to improving the energy-saving effect of the air-conditioning system. On the contrary, when the indoor environmental humidity is high, the demand for dehumidification is high. The disclosed embodiment can set a relatively large second dehumidification temperature difference to determine a second target evaporation temperature that is much lower than the current dew point temperature, so that the dehumidification efficiency of the second indoor heat exchanger can be improved to match the current larger dehumidification demand. In this way, the dehumidification effect of the air-conditioning system can be reasonably improved, which is conducive to better ensuring the user's comfort experience.

[0105] Optionally, the processor determines the first target evaporation temperature of the first indoor heat exchanger, including: the processor determines the current dew point temperature according to the indoor ambient temperature and the indoor ambient humidity; the processor determines the first dehumidification temperature difference according to the difference between the indoor ambient temperature and the target comfort temperature; the processor calculates the sum of the current dew point temperature and the first dehumidification temperature difference to obtain the first target evaporation temperature of the first indoor heat exchanger. In this way, the embodiment of the present disclosure can reasonably set the first dehumidification temperature difference in combination with the difference between the current indoor ambient temperature and the target comfort temperature to determine the amplitude by which the first target evaporation temperature is greater than the dew point temperature, thereby controlling the actual cooling efficiency of the first indoor heat exchanger so that it can accurately match the current cooling and dehumidification process, which is conducive to taking into account both the cooling effect and the energy-saving effect of the air-conditioning system.

[0106] Optionally, the first dehumidification temperature difference is negatively correlated with the difference between the indoor ambient temperature and the target comfort temperature. Specifically, in some embodiments, when the difference between the indoor ambient temperature and the target comfort temperature (such as 27°C) is greater than or equal to 3°C, the first dehumidification temperature difference is determined to be 0.5°C; or, when the difference between the indoor ambient temperature and the target comfort temperature (such as 27°C) is less than 3°C, the first dehumidification temperature difference is determined to be 1°C. The relevant values ​​can be adaptively adjusted according to the actual needs of the user, and can also be set to any other values ​​that meet the above negative correlation.

[0107] In this way, when the indoor ambient temperature is much higher than the target comfort temperature, the demand for cooling capacity is relatively large. The disclosed embodiment can set a relatively small first dehumidification temperature difference to determine a first target evaporation temperature that is closer to the current dew point temperature, so that the cooling efficiency of the first indoor heat exchanger can be appropriately improved to match the current larger cooling capacity demand. In this way, the cooling effect of the air-conditioning system can be reasonably improved, which is conducive to better ensuring the user's comfort experience. On the contrary, when the indoor ambient temperature is close to the target comfort temperature, the demand for cooling capacity is relatively small. The disclosed embodiment can set a relatively large first dehumidification temperature difference to determine a first target evaporation temperature that is greater than the current dew point temperature, so that the cooling efficiency of the first indoor heat exchanger can be reduced to match the current smaller cooling capacity demand. While ensuring the cooling effect, the indoor air supply temperature can also be increased, which is conducive to ensuring the user's comfort experience, and can further reduce the system energy consumption, which is conducive to improving the energy-saving effect of the air-conditioning system.

[0108] Optionally, the processor adjusts the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the first target evaporation temperature, including: when the evaporation temperature of the first indoor heat exchanger is greater than the first target evaporation temperature, the processor reduces the opening of the first throttle valve; or, when the evaporation temperature of the first indoor heat exchanger is less than the first target evaporation temperature, the processor increases the opening of the first throttle valve. In this way, when the evaporation temperature of the first indoor heat exchanger is greater than the first target evaporation temperature, it indicates that the evaporation temperature of the first indoor heat exchanger is too high at this time, and the cooling effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure reduces the opening of the first throttle valve, so as to reduce the refrigerant flow through the first indoor heat exchanger, so as to appropriately reduce the evaporation pressure of the first indoor heat exchanger, and then the evaporation temperature of the first indoor heat exchanger can be gradually reduced and approach the first target evaporation temperature. When the evaporation temperature of the first indoor heat exchanger is less than the first target evaporation temperature, it indicates that the evaporation temperature of the first indoor heat exchanger is too low at this time, and the energy-saving effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure increases the opening of the first throttle valve, thereby increasing the refrigerant flow through the first indoor heat exchanger, so as to appropriately increase the evaporation pressure of the first indoor heat exchanger, thereby enabling the evaporation temperature of the first indoor heat exchanger to gradually rise and approach the first target evaporation temperature. Thus, the embodiment of the present disclosure can achieve precise regulation of the evaporation temperature corresponding to the first indoor heat exchanger, so that it can gradually stabilize near the first target evaporation temperature greater than the dew point temperature.

[0109] Optionally, the processor may use a PID algorithm to increase or decrease the opening of the first throttle valve, and the corresponding PID adjustment value may be a fixed number of steps or a fixed ratio. Optionally, the PID adjustment value is positively correlated with the absolute value of the first real-time temperature difference between the evaporation temperature of the first indoor heat exchanger and the first target evaporation temperature. In this way, the embodiment of the present disclosure can achieve precise adjustment of the evaporation temperature corresponding to the first indoor heat exchanger, so that it can gradually stabilize near the first target evaporation temperature greater than the dew point temperature.

[0110] Optionally, the processor adjusts the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger approaches the second target evaporation temperature, including: when the evaporation temperature of the second indoor heat exchanger is greater than the second target evaporation temperature, the processor reduces the opening of the second throttle valve; or, when the evaporation temperature of the second indoor heat exchanger is less than the second target evaporation temperature, the processor increases the opening of the second throttle valve. In this way, when the evaporation temperature of the second indoor heat exchanger is greater than the second target evaporation temperature, it indicates that the evaporation temperature of the second indoor heat exchanger is too high at this time, and the dehumidification effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure reduces the opening of the second throttle valve, so as to reduce the refrigerant flow through the second indoor heat exchanger, so as to appropriately reduce the evaporation pressure of the second indoor heat exchanger, and then the evaporation temperature of the second indoor heat exchanger can be gradually reduced and approach the second target evaporation temperature. When the evaporation temperature of the second indoor heat exchanger is less than the second target evaporation temperature, it indicates that the evaporation temperature of the second indoor heat exchanger is too low at this time, and the energy-saving effect of the air-conditioning system is not good. Therefore, the embodiment of the present disclosure increases the opening of the second throttle valve, thereby increasing the refrigerant flow through the second indoor heat exchanger, so as to appropriately increase the evaporation pressure of the second indoor heat exchanger, thereby enabling the evaporation temperature of the second indoor heat exchanger to gradually rise and approach the second target evaporation temperature. Thus, the embodiment of the present disclosure can achieve precise regulation of the evaporation temperature corresponding to the second indoor heat exchanger, so that it can gradually stabilize near the second target evaporation temperature that is less than the dew point temperature.

[0111] Optionally, the processor may use a PID algorithm to increase or decrease the opening of the second throttle valve, and the corresponding PID adjustment value may be a fixed number of steps or a fixed ratio. Optionally, the PID adjustment value is positively correlated with the absolute value of the second real-time temperature difference between the evaporation temperature of the second indoor heat exchanger and the second target evaporation temperature. In this way, the embodiment of the present disclosure can achieve precise adjustment of the evaporation temperature corresponding to the second indoor heat exchanger, so that it can gradually stabilize near the second target evaporation temperature that is less than the dew point temperature.

[0112] Optionally, after the processor determines the first target evaporation temperature of the first indoor heat exchanger and determines the second target evaporation temperature of the second indoor heat exchanger, it also includes: the processor obtains the first real-time temperature difference between the evaporation temperature of the first indoor heat exchanger and the first target evaporation temperature, and obtains the second real-time temperature difference between the evaporation temperature of the second indoor heat exchanger and the second target evaporation temperature; the processor determines the target adjustment object according to the first real-time temperature difference and the second real-time temperature difference, so as to adjust the opening of the first throttle valve and / or the opening of the second throttle valve according to the target adjustment object. In this way, considering that the refrigerant flowing through the first indoor heat exchanger and the refrigerant flowing through the second indoor heat exchanger will affect each other, the embodiment of the present disclosure also determines the target adjustment object according to the first real-time temperature difference and the second real-time temperature difference before adjusting the opening, so that the opening of the first throttle valve and / or the opening of the second throttle valve can be selectively adjusted to avoid the two opening adjustment actions interfering with each other and causing the evaporation temperature of a certain indoor heat exchanger to deviate from its corresponding target evaporation temperature.

[0113] Combination Figure 8 As shown, the embodiment of the present disclosure provides a control device 80 for an air conditioning system, including a processor 81 and a memory 82. Optionally, the control device 80 may also include a communication interface 83 and a bus 84. The processor 81, the communication interface 83, and the memory 82 may communicate with each other through the bus 84. The communication interface 83 may be used for information transmission. The processor 81 may call the logic instructions in the memory 82 to execute the control method for the air conditioning system of the above embodiment.

[0114] In addition, the logic instructions in the memory 82 described above may be implemented in the form of software functional units and when sold or used as independent products, may be stored in a computer-readable storage medium.

[0115] The memory 82 is a computer-readable storage medium that can be used to store software programs and computer executable programs, such as program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 81 executes the function application and data processing by running the program instructions / modules stored in the memory 82, that is, the control method for the air conditioning system in the above embodiment is implemented.

[0116] The memory 82 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required for at least one function; the data storage area may store data created according to the use of the terminal device, etc. In addition, the memory 82 may include a high-speed random access memory and may also include a non-volatile memory.

[0117] Combination Fig. 9As shown, an embodiment of the present disclosure provides an air conditioner, including: an indoor unit 200, and the above-mentioned control device 80 for an air conditioning system. The control device 80 for an air conditioning system is installed in the indoor unit 200. The installation relationship described here is not limited to being placed inside the indoor unit 200, but also includes installation connections with other components of the air conditioner, including but not limited to physical connections, electrical connections, or signal transmission connections. It can be understood by those skilled in the art that the control device 80 for an air conditioning system can be adapted to a feasible air conditioner body, thereby realizing other feasible embodiments.

[0118] An embodiment of the present disclosure provides a computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to execute the above-mentioned control method for an air-conditioning system.

[0119] The technical solution of the embodiment of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiment of the present disclosure. The aforementioned storage medium may be a non-transient storage medium, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes.

[0120] The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible changes. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. The parts and features of some embodiments may be included in or replace the parts and features of other embodiments. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and the claims, unless the context clearly indicates, the singular forms of "a", "an" and "the" are intended to include plural forms as well. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of listings containing one or more associated ones. In addition, when used in the present application, the term "comprise" and its variants "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method or device comprising the elements. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments may refer to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts can refer to the description of the method part.

[0121] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods for each specific application to implement the described functions, but such implementations should not be considered to exceed the scope of the embodiments of the present disclosure. The technicians may clearly understand that, for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above may refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

[0122] In the embodiments disclosed herein, the disclosed methods and products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units can be only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to implement this embodiment. In addition, each functional unit in the embodiment of the present disclosure may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

[0123] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A control method for an air conditioning system, It is characterized in that The air conditioning system comprises: a compressor, comprising a medium-pressure cylinder and a low-pressure cylinder; a four-way valve, connected to an exhaust pipeline of the compressor and to an air suction pipeline of the medium-pressure cylinder; a three-way valve, connected to an exhaust pipeline of the compressor and to an air suction pipeline of the low-pressure cylinder; an outdoor heat exchanger, connected to the four-way valve; a first indoor heat exchanger, connected to the outdoor heat exchanger and to the four-way valve; a second indoor heat exchanger, connected in parallel with the first indoor heat exchanger and connected to the three-way valve; a first throttle valve, provided at an inlet pipeline of the first indoor heat exchanger in a cooling mode; a second throttle valve, provided at an inlet pipeline of the second indoor heat exchanger in a cooling mode; the method comprises: When the air conditioning system enters the dual evaporation temperature cooling mode, determining a third target evaporation temperature of the first indoor heat exchanger, and determining a target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger; adjusting the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature; The opening degree of the second throttle valve is adjusted so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference.

2. The method according to claim 1, It is characterized in that Determining a third target evaporation temperature of the first indoor heat exchanger includes: Determine the target cooling temperature difference according to the difference between the indoor ambient temperature and the target set temperature; Calculating the difference between the target set temperature and the target cooling temperature difference to obtain a third target evaporation temperature of the first indoor heat exchanger; Among them, the target cooling temperature difference is positively correlated with the difference between the indoor ambient temperature and the target set temperature.

3. The method according to claim 1, It is characterized in that Determining a target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger includes: Determining a target evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger according to the indoor ambient humidity; Among them, the target evaporation temperature difference is positively correlated with the indoor ambient humidity.

4. The method according to claim 1, It is characterized in that Adjusting the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the third target evaporation temperature includes: When the evaporation temperature of the first indoor heat exchanger is greater than the third target evaporation temperature, reducing the opening of the first throttle valve; or, When the evaporating temperature of the first indoor heat exchanger is lower than the third target evaporating temperature, the opening degree of the first throttle valve is increased.

5. The method according to claim 1, It is characterized in that Adjusting the opening of the second throttle valve so that the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger approaches the target evaporation temperature difference includes: When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, increasing the opening of the second throttle valve; or, When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is smaller than the target evaporation temperature difference, the opening degree of the second throttle valve is reduced.

6. The method according to claim 5, It is characterized in that When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is greater than the target evaporation temperature difference, the method further includes: When the evaporation temperature of the second indoor heat exchanger is greater than the first protection temperature, the opening of the second throttle valve is maintained unchanged and the opening of the first throttle valve is reduced.

7. The method according to claim 5, It is characterized in that When the evaporation temperature difference between the first indoor heat exchanger and the second indoor heat exchanger is less than the target evaporation temperature difference, the method further includes: When the evaporation temperature of the second indoor heat exchanger is lower than the second protection temperature, the opening of the second throttle valve is maintained unchanged, and the opening of the first throttle valve is increased.

8. The method according to any one of claims 1 to 7, It is characterized in that Also includes: Obtain the suction pressure of the medium-pressure cylinder and the suction pressure of the low-pressure cylinder; When the difference between the suction pressure of the medium-pressure cylinder and the suction pressure of the low-pressure cylinder is smaller than the preset pressure difference, the opening difference between the first throttle valve and the second throttle valve is increased.

9. The method according to any one of claims 1 to 7, It is characterized in that Also includes: In response to a cooling instruction, obtaining a difference between an indoor ambient temperature and a target set temperature; When the difference between the indoor ambient temperature and the target set temperature is greater than or equal to a first preset temperature difference, the air conditioning system is controlled to enter a fast cooling mode; or, When the difference between the indoor ambient temperature and the target set temperature is less than the first preset temperature difference and greater than or equal to the second preset temperature difference, the air conditioning system is controlled to enter the dual evaporation temperature cooling mode; or, When the difference between the indoor ambient temperature and the target set temperature is less than the second preset temperature difference, the air conditioning system is controlled to enter a cool but not cold mode.

10. The method according to any one of claims 1 to 7, It is characterized in that Also includes: In the case where the air conditioning system enters the dual evaporation temperature dehumidification mode, determining a first target evaporation temperature of the first indoor heat exchanger, and determining a second target evaporation temperature of the second indoor heat exchanger; adjusting the opening of the first throttle valve so that the evaporation temperature of the first indoor heat exchanger approaches the first target evaporation temperature; adjusting the opening of the second throttle valve so that the evaporation temperature of the second indoor heat exchanger approaches the second target evaporation temperature; The first target evaporation temperature is greater than the dew point temperature, and the second target evaporation temperature is less than the dew point temperature.

11. A control device for an air conditioning system, comprising a processor and a memory storing program instructions, It is characterized in that The processor is configured to execute the control method for an air conditioning system according to any one of claims 1 to 10 when running the program instructions.

12. An air conditioning system, It is characterized in that include: A compressor, including an intermediate pressure cylinder and a low pressure cylinder; A four-way valve connected to the exhaust line of the compressor and to the suction line of the intermediate pressure cylinder; A three-way valve connected to the exhaust line of the compressor and to the suction line of the low-pressure cylinder; An outdoor heat exchanger is connected to a four-way valve; A first indoor heat exchanger is connected to the outdoor heat exchanger and is connected to the four-way valve; A second indoor heat exchanger is connected in parallel with the first indoor heat exchanger and is communicated with the three-way valve; a first throttle valve, arranged on an inlet pipeline of the first indoor heat exchanger in a cooling mode; a second throttle valve, arranged on the inlet pipeline of the second indoor heat exchanger in the cooling mode; The control device for an air conditioning system as claimed in claim 11 is electrically connected to the first throttle valve and the second throttle valve respectively.

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