WO2023207050A1 - Air-conditioning system and control method for air-conditioning system - Google Patents

Abstract

An air-conditioning system, comprising an outdoor unit, an indoor unit and a controller. The outdoor unit comprises a compressor, an outdoor electronic expansion valve and an outdoor heat exchanger; and the indoor unit comprises an indoor electronic expansion valve and an indoor heat exchanger. The controller is configured to: acquire an opening degree of the indoor electronic expansion valve; and when the outdoor heat exchanger condenses a refrigerant, if a first preset condition is met, adjust an opening degree of the outdoor electronic expansion valve according to the relationship between a supercooling degree of the outdoor heat exchanger and a first target supercooling degree interval, and adjust the opening degree of the indoor electronic expansion valve according to the relationship between an exhaust superheating degree of the compressor and a target exhaust superheating degree interval. The first preset condition comprises the opening degree of the indoor electronic expansion valve being less than a first preset opening degree.

Description

Air conditioning system and control method of air conditioning system

This application claims the priority of the Chinese patent application with application number 202210439309.5 submitted on April 25, 2022, and the priority of the Chinese patent application with application number 202210609487.8 submitted on May 31, 2022, all of which The contents are incorporated into this application by reference.

Technical field

The present disclosure relates to the technical field of air conditioning, and in particular, to an air conditioning system and a control method of the air conditioning system.

Background technique

As people's living standards continue to improve, more and more places have installed air conditioning systems to bring people a better life experience. The amount of refrigerant in the air conditioning system affects its performance. Usually, the refrigerant charging amount in the air conditioning system is mostly obtained through the experience of the installer or precise calculations. Therefore, the refrigerant charging amount may be inaccurate, resulting in air conditioner failure. System performance is reduced.

Contents of the invention

In one aspect, an air conditioning system is provided. The air conditioning system includes an outdoor unit, an indoor unit and a controller. The outdoor unit includes a compressor, outdoor electronic expansion valve and outdoor heat exchanger; the indoor unit includes an indoor electronic expansion valve and indoor heat exchanger. Among them, the compressor compresses the refrigerant and discharges the compressed refrigerant, the outdoor heat exchanger condenses the compressed refrigerant, and the outdoor electronic expansion valve and the indoor electronic expansion valve respectively control the amount of refrigerant condensed by the outdoor heat exchanger. Adjustment, the indoor heat exchanger evaporates the refrigerant adjusted by the indoor electronic expansion valve. The controller is configured to: obtain the opening of the indoor electronic expansion valve; when the first preset condition is met, adjust the outdoor electronic expansion according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval. The opening of the indoor electronic expansion valve is adjusted based on the relationship between the exhaust superheat of the compressor and the target exhaust superheat range. When the first preset condition is not met, the opening of the outdoor electronic expansion valve and the opening of the indoor electronic expansion valve are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. Wherein, the first preset condition includes that the opening of the indoor electronic expansion valve is smaller than the first preset opening.

On the other hand, a control method for an air conditioning system is provided. The air conditioning system includes an outdoor unit, an indoor unit and a controller. The outdoor unit includes a compressor, outdoor electronic expansion valve and outdoor heat exchanger. The indoor unit includes an indoor electronic expansion valve and an indoor heat exchanger. Among them, the compressor compresses the refrigerant and discharges the compressed refrigerant, the outdoor heat exchanger condenses the compressed refrigerant, and the outdoor electronic expansion valve and the indoor electronic expansion valve respectively control the amount of refrigerant condensed by the outdoor heat exchanger. Adjustment, the indoor heat exchanger evaporates the refrigerant adjusted by the indoor electronic expansion valve. The control method of the air conditioning system includes: obtaining the opening of the indoor electronic expansion valve; when the first preset condition is met, adjusting the outdoor electronic expansion valve according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree range. The opening of the expansion valve and the opening of the indoor electronic expansion valve are adjusted based on the relationship between the exhaust superheat of the compressor and the target exhaust superheat range. When the first preset condition is not met, the opening of the outdoor electronic expansion valve and the opening of the indoor electronic expansion valve are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. Wherein, the first preset condition includes that the opening of the indoor electronic expansion valve is smaller than the first preset opening.

Description of drawings

In order to explain the technical solutions in the present disclosure more clearly, the drawings required to be used in some embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings in the following description are only the drawings of some embodiments of the present disclosure. , for those of ordinary skill in the art, other drawings can also be obtained based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of the present disclosure.

Figure 1 is a structural diagram of an air conditioning system according to some embodiments of the present disclosure;

Figure 2 is a schematic diagram of a controller according to some embodiments of the present disclosure;

Figure 3 is a schematic diagram of an air conditioning system according to some embodiments of the present disclosure;

Figure 4A is a schematic diagram of another air conditioning system according to some embodiments of the present disclosure;

Figure 4B is a pressure-enthalpy diagram according to some embodiments of the present disclosure;

Figure 5 is a flow chart of a control mode according to some embodiments of the present disclosure;

Figure 6 is a flow chart of another control mode according to some embodiments of the present disclosure;

Figure 7 is a flow chart of a control method for an air conditioning system according to some embodiments of the present disclosure;

Figure 8 is a flow chart of yet another control mode according to some embodiments of the present disclosure;

Figure 9 is a flow chart of yet another control mode according to some embodiments of the present disclosure;

Figure 10 is a flow chart of another control method of an air conditioning system according to some embodiments of the present disclosure;

Figure 11 is a structural diagram of yet another air conditioning system according to some embodiments of the present disclosure;

Figure 12A is a structural diagram of a liquid phase branch pipe according to some embodiments of the present disclosure;

Figure 12B is a structural diagram of another liquid phase branch pipe according to some embodiments of the present disclosure;

Figure 13 is a structural diagram of yet another liquid phase branch pipe according to some embodiments of the present disclosure;

Figure 14 is a structural diagram of a first flow tube according to some embodiments of the present disclosure;

Figure 15 is a structural view of the first flow tube along line A-A in Figure 14;

Figure 16 is a partially enlarged schematic diagram of part D in Figure 15;

Figure 17 is another partially enlarged schematic diagram of part D in Figure 15;

Figure 18 is another partially enlarged schematic diagram of part D in Figure 15;

Figure 19 is a structural view of the first flow tube along line B-B in Figure 14;

Figure 20 is a structural diagram of a first orifice plate mixed flow plate according to some embodiments of the present disclosure;

Figure 21 is a structural view of the first flow tube along line C-C in Figure 14;

Figure 22 is a structural diagram of a second orifice plate mixed flow plate according to some embodiments of the present disclosure;

Figure 23 is a structural diagram of another second orifice plate mixed flow plate according to some embodiments of the present disclosure;

Figure 24 is a structural diagram of yet another second orifice plate mixed flow plate according to some embodiments of the present disclosure;

Figure 25 is a schematic diagram of multiple flow mixing members in the first flow tube according to some embodiments of the present disclosure;

Figure 26 is a flowchart of yet another control method of an air conditioning system according to some embodiments of the present disclosure.

Detailed ways

The technical solutions in some embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments provided by this disclosure, all other embodiments obtained by those of ordinary skill in the art fall within the scope of protection of this disclosure.

Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and its other forms such as the third person singular "comprises" and the present participle "comprising" are used. Interpreted as open and inclusive, it means "including, but not limited to." In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific "example" or "some examples" and the like are intended to indicate that a particular feature, structure, material or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be included in any suitable manner in any one or more embodiments or examples.

Hereinafter, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

In describing some embodiments, expressions "coupled" and "connected" and their derivatives may be used. The term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integrated connection; it can be a direct connection or an indirect connection through an intermediate medium. The term "coupled" is used to indicate that two or more components are in direct physical or electrical contact. However, the terms "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited by the content herein.

"At least one of A, B and C" has the same meaning as "at least one of A, B or C" and includes the following combinations of A, B and C: A only, B only, C only, A and B The combination of A and C, the combination of B and C, and the combination of A, B and C.

"A and/or B" includes the following three combinations: A only, B only, and a combination of A and B.

As used herein, the term "if" is optionally interpreted to mean "when" or "in response to" or "in response to determining" or "in response to detecting," depending on the context. Similarly, depending on the context, the phrase "if it is determined..." or "if [stated condition or event] is detected" is optionally interpreted to mean "when it is determined..." or "in response to the determination..." or “on detection of [stated condition or event]” or “in response to detection of [stated condition or event]”.

The use of "suitable for" or "configured to" in this document implies open and inclusive language that does not exclude devices that are suitable for or configured to perform additional tasks or steps.

Additionally, the use of "based on" is meant to be open and inclusive in that a process, step, calculation or other action "based on" one or more stated conditions or values may in practice be based on additional conditions or beyond the stated values.

Refrigerant is a substance that can turn into a gas by absorbing heat and turn into a liquid by releasing heat. In the air conditioning system, the refrigerant transfers energy through evaporation or condensation in the indoor heat exchanger and outdoor heat exchanger respectively to produce cooling or heating effects. The amount of refrigerant contained in an air conditioning system is critical to its performance and reliability.

The amount of refrigerant in an air conditioning system is critical to system performance and reliability. When the amount of refrigerant is relatively too much, the amount of refrigerant remaining in the condenser will be large, the pressure will be high, the energy efficiency of the unit will be low, and the unit may have reliability problems; when the amount of refrigerant is relatively too small, the amount of refrigerant remaining in the condenser will be insufficient, the degree of subcooling will be small, The dryness entering the evaporator is large, resulting in reduced capacity.

Figure 1 is a structural diagram of an air conditioning system provided by some embodiments of the present disclosure. As shown in FIG. 1 , the air conditioning system 1 includes an outdoor unit 10 and an indoor unit 20 . Illustratively, in some embodiments of the present disclosure, the air conditioning system 1 may include multiple indoor units 20, such as the two indoor units 20 in Figure 1 .

Referring to Figure 1, in the air conditioning system 1, the outdoor unit 10 includes a gas-liquid separator 101, a compressor 102, an outdoor heat exchanger 103, an outdoor electronic expansion valve 104, a liquid side stop valve 105, a gas side stop valve 110 and a four-way Valve 111; the indoor unit 20 includes an indoor electronic expansion valve 107 (including a first indoor electronic expansion valve 1071 and a second indoor electronic expansion valve 1072), an indoor heat exchanger 108 (including a first indoor heat exchanger 1081 and a second indoor heat exchanger). Heater 1082). The first indoor unit 21 includes a first indoor electronic expansion valve 1071 and a first indoor heat exchanger 1081 , and the second indoor unit 22 includes a second indoor electronic expansion valve 1072 and a second indoor heat exchanger 1082 .

In some embodiments, the outdoor unit 10 and the indoor unit 20 may be connected through an online liquid pipe 106 and an online air pipe 109 respectively.

For example, the openings of the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 will affect the flow rate of the refrigerant in the air conditioning system 1 . For example, when the opening degrees of the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 change, the flow rate of the refrigerant in the air conditioning system 1 also changes.

In some embodiments, the outdoor unit 10 further includes an outdoor fan and/or an outdoor fan motor. Among them, the outdoor fan motor is used to drive or change the speed of the outdoor fan.

In some embodiments, the indoor unit 20 further includes one or more of the following: a display, an indoor fan, and an indoor fan motor. Among them, the display is used to display the indoor temperature or operating mode; the indoor fan motor is used to drive or change the speed of the indoor fan.

In some embodiments, the air conditioning system 1 further includes a controller. As shown in FIG. 2 , the controller 30 includes an outdoor controller 31 and an indoor controller 32 . The indoor controller 32 can be coupled with the outdoor controller 31 through wired or wireless communication. The outdoor controller 31 can be installed in the outdoor unit 10 , or can be installed independently outside the outdoor unit 10 . The outdoor controller 31 is used to control components in the outdoor unit 10 to perform relevant operations. The indoor controller 32 may be installed in the indoor unit 20 or may be installed independently outside the indoor unit 20 to control components in the indoor unit 20 to perform relevant operations.

For example, the controller 30 can be a central processing unit (Central Processing Unit, CPU), a general-purpose processor, a network processor (Network Processor, NP), a digital signal processor (Digital Signal Processing, DSP), a microprocessor, a microprocessor Controller, Programmable Logic Device (PLD) or any combination thereof. The controller 30 may also be other devices with processing functions, such as circuits, devices or software modules. The controller 30 can be used to control the operation of each component in the air conditioning system 1, so that each component in the air conditioning system 1 operates to achieve each predetermined function.

In some embodiments, as shown in FIG. 2 , the outdoor controller 31 may include a first memory 311 and the indoor controller 32 may include a second memory 321 . The first memory 311 and the second memory 321 may respectively include high-speed random access memory, or may also include non-volatile memory, such as a magnetic disk storage device, a flash memory device or other volatile solid-state storage devices. It should be noted that the division of components in some embodiments of the present disclosure is only functional division. For example, the outdoor controller 31 and the indoor controller 32 can also be integrated into one controller; the first memory 311 and the second memory 321 are, for example, It can also be integrated into a memory. This disclosure does not limit this.

For example, the first memory 311 is used to store application programs and data related to the outdoor unit 10, such as opening information of the outdoor electronic expansion valve 104, etc. The outdoor controller 31 executes various functions and data processing of the air conditioning system 1 by running the application program and data stored in the first memory 311 . The second memory 321 is used to store application programs and data related to the indoor unit 20 . The indoor controller 32 executes various functions and data processing of the air conditioning system 1 by running the application programs and data stored in the second memory 321 . For example, the opening degree information of the indoor electronic expansion valve 107, etc.

In some embodiments, there is a communication connection between the outdoor controller 31 and the outdoor unit 10 for controlling the outdoor unit 10 to perform relevant operations according to relevant instructions. For example, the outdoor controller 31 can control the opening of the outdoor electronic expansion valve 104 according to the exhaust superheat of the compressor 102; the outdoor controller 31 can also obtain the outdoor ambient temperature and store the obtained outdoor ambient temperature in the first memory 311 , and adjust the opening of the outdoor electronic expansion valve 104 according to the outdoor ambient temperature; the outdoor controller 31 can also control the rotation of the four-way valve 111 according to relevant instructions to control the air conditioning system 1 to perform cooling or heating.

In some embodiments, the indoor controller 32 is communicatively connected with the indoor unit 20 and is used to control the indoor unit 20 to perform relevant operations according to relevant instructions. For example, the indoor controller 32 can control the opening of the indoor electronic expansion valve 107 according to the exhaust superheat of the compressor 102; or, the indoor controller 32 can also obtain the indoor ambient temperature according to relevant instructions.

Figure 3 is a schematic diagram of an air conditioning system 1 provided by some embodiments of the present disclosure. In some embodiments, as shown in FIG. 3 , the air conditioning system 1 may further include a first temperature sensor 113 , a compressor exhaust pressure sensor 114 , a compressor exhaust temperature sensor 115 , and a second temperature sensor 113 , respectively coupled to the controller 30 . Temperature sensor 116, third temperature sensor 117, and communicator 118.

For example, the position distribution of the first temperature sensor 113, the compressor exhaust pressure sensor 114, the compressor exhaust temperature sensor 115, the second temperature sensor 116, and the third temperature sensor 117 is as shown in FIG. 4A. As shown in FIG. 4A , one end of the first temperature sensor 113 is connected to the outdoor electronic expansion valve 104 and the other end is connected to the outdoor heat exchanger 103 for detecting the temperature of the refrigerant at the outlet of the outdoor heat exchanger 103 . The compressor discharge pressure sensor 114 can be located at the discharge port of the compressor 102 and used to detect the pressure of the refrigerant gas discharged from the compressor 102 . The compressor exhaust temperature sensor 115 may also be set at the exhaust port of the compressor 102 to detect the temperature of the refrigerant gas discharged from the compressor 102 . One end of the second temperature sensor 116 is connected to the indoor electronic expansion valve 107, and the other end is connected to the indoor heat exchanger 108, for detecting the temperature of the refrigerant at the outlet of the indoor heat exchanger 108. The third temperature sensor 117 has one end connected to the indoor heat exchanger 108 and the other end connected to the online air pipe 109 for detecting the refrigerant temperature at the other outlet of the indoor unit heat exchanger.

In some embodiments, the communicator 118 is used to establish a communication connection with other network entities. For example, the communicator 118 can establish a communication connection with a terminal device. The air-conditioning system 1 can receive control instructions sent by the terminal device through the communicator 118 and perform the control according to the communicator 118. control instructions and execute corresponding processing to realize the interaction between the user and the air conditioning system 1. For example, the communicator 118 may include a radio frequency (Radio Frequency, RF) component, a cellular component, a Wireless Fidelity (WIFI) component, a GPS component, etc. For example, the RF component may be used to send received information to the controller 30 for processing and to send signals generated by the controller 30. Exemplarily, the RF component may include, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc.

In some embodiments, the air conditioning system 1 may also include a remote control, which may communicate with the controller 30 using infrared rays or other communication methods. For example, the user can perform various control operations on the air conditioning system 1 through the remote control to realize interaction between the user and the air conditioning system 1 .

For example, the refrigerant amount of the air conditioning system 1 includes the original amount of refrigerant in the air conditioning system 1 (such as the refrigerant charging amount of the outdoor unit 10) and the additional refrigerant amount. The additional amount of refrigerant needs to be determined based on the online piping between the outdoor unit 10 and the indoor unit 20 . For example, the length of the online liquid pipe 106 shown in FIG. 1 is usually related to the installation environment of the outdoor unit 10 and the indoor unit 20. Different pipe lengths require different additional amounts of refrigerant. Therefore, when installing the air conditioning system 1, the installer needs to calculate the additional amount of refrigerant based on the online piping length, pipe diameter, additional refrigerant calculation method and other information. If the additional refrigerant amount is inaccurate, the performance of the air conditioning system 1 will decrease.

In the related technology, the air conditioning system 1 can be added without additional refrigerant by adding components such as a liquid reservoir, but it is still necessary to provide sufficient refrigerant (i.e., the original amount of refrigerant plus the additional refrigerant amount) to ensure that the air conditioner The normal operation of system 1 has the problem of complex structure and high cost of air conditioning system 1.

The air conditioning system 1 provided by some embodiments of the present disclosure can realize the elimination of additional refrigerant, so that the air conditioning system 1 can still operate normally with the original amount of refrigerant, avoiding the air conditioning system after installation due to inaccurate calculation of the refrigerant by the installer. 1, the structure of the air conditioning system 1 is simplified, the cost is reduced, and the reliability of the air conditioning system 1 is improved.

For example, when the length of the online piping (such as the maximum charging-free online piping) is L0, the corresponding refrigerant charging amount of the air conditioning system in the related art is M1, and the refrigerant charging amount of the air conditioning system 1 provided by the embodiment of the present disclosure is M0. , M1>M0.

The following describes the working process of the air conditioning system 1 with reference to FIG. 4A , taking the cooling of the air conditioning system 1 as an example. For example, when the air conditioning system 1 performs cooling, the outdoor heat exchanger 103 is a condenser and the indoor heat exchanger 108 is an evaporator. The direction of the arrow in FIG. 4A is the flow direction of the refrigerant during cooling by the air conditioning system 1 . Among them, the compressor 102 controls the evaporation temperature of the indoor unit 20. The compressor 102 sucks the low-pressure superheated refrigerant from the gas-liquid separator 101 (the refrigerant state at point A in Figure 4A), and compresses it to high-temperature and high-pressure refrigerant, which flows through The four-way valve 111 is discharged back to the outdoor heat exchanger 103 (the refrigerant state at point B in Figure 4A); in the outdoor heat exchanger 103, the high-temperature and high-pressure refrigerant exchanges heat with the air and is cooled into high-pressure supercooled liquid refrigerant ( As shown in the refrigerant state at point C in Figure 4A); the outdoor electronic expansion valve 104 is in a fully open state, and the high-pressure supercooled liquid refrigerant passes through the outdoor electronic expansion valve 104 and is enthalpy-throttled to point D; the refrigerant at point D passes through the online liquid pipe 106 Isoenthalpic throttling reduces the pressure to point E; the indoor electronic expansion valve 107 controls the superheat of the indoor heat exchanger 108 and the exhaust superheat of the compressor 102, throttling the high-pressure liquid refrigerant to the low-pressure gas-liquid two-phase state ( Such as the refrigerant state at point F in Figure 4A); after the refrigerant at point F enters the indoor heat exchanger 108, it evaporates into a low-pressure superheated gas state (the refrigerant state at point G in Figure 4A).

FIG. 4B provides a pressure-enthalpy diagram according to an embodiment of the present disclosure, for example, a pressure-enthalpy diagram when the air conditioning system 1 is in the cooling mode. Among them, A-B'-C'-D'-E'-F' can be used to represent the pressure-enthalpy diagram of the operation of the air-conditioning system in the related art when the refrigerant amount is M0; A-B-C-D-E-F is the pressure-enthalpy diagram of the air-conditioning system 1 when the refrigerant amount is M0 Pressure-enthalpy diagram for operation at M0. Referring to Figure 4B, when the air-conditioning system in the related art operates with a refrigerant amount of M0, due to insufficient refrigerant amount, the outlet C' of the condenser will have no subcooling, and the outlet will be in a two-phase state. After fully open outdoor electronic expansion The pressure loss behind the valve 104 is reduced to the state of D' refrigerant, the pressure loss is reduced to the state of E' refrigerant through the online liquid pipe 106, and the indoor electronic expansion valve 107 is throttled to the state of F' refrigerant. Due to the lack of refrigerant, there is no subcooling at the condenser outlet, resulting in high dryness at the evaporator inlet and lack of liquid refrigerant, which leads to a decrease in the evaporation capacity of the evaporator and a decrease in the refrigeration performance of the air conditioning system 1. Continuing to refer to Figure 4B, in the air conditioning system 1, the subcooling degree of the refrigerant at point C at the condenser outlet is greater than the subcooling degree of the refrigerant at point C', which ensures that the refrigerant after the outdoor electronic expansion valve 107 is in a medium-pressure two-phase state and is online The amount of refrigerant in the liquid pipe 106 decreases, and the amount of refrigerant at the condenser outlet increases. Therefore, the dryness entering the evaporator decreases, and the cooling capacity of the air conditioning system 1 is improved. The heating process of the air conditioning system 1 is similar and will not be described again here.

The controller 30 detects the subcooling degree of the refrigerant at the outlet of the outdoor heat exchanger 103. When the subcooling degree of the refrigerant at the outlet of the outdoor heat exchanger 103 is less than the preset subcooling degree, the controller 30 will reduce the opening of the outdoor electronic expansion valve 104 to The refrigerant passing through the outdoor electronic expansion valve 104 is throttled to a gas-liquid two-phase state of medium and low pressure. That is to say, the refrigerant flowing through the online liquid pipe 106 is in a gas-liquid two-phase state, thereby reducing the amount of refrigerant in the online liquid pipe 106. The remaining amount increases the subcooling degree at the outlet of the outdoor heat exchanger 103, reduces the dryness of the indoor heat exchanger 108, and improves the cooling capacity of the indoor heat exchanger 108. For example, the amount of refrigerant that increases the subcooling degree of the outdoor heat exchanger 103 comes from the reduction of the refrigerant in the online liquid pipe 106 .

In some embodiments, the compressor 102 compresses the refrigerant and discharges the compressed refrigerant, the outdoor heat exchanger 103 condenses the compressed refrigerant, and the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 sequentially condense the outdoor heat exchanger. 103 adjusts the amount of condensed refrigerant, and the indoor heat exchanger 108 evaporates the refrigerant adjusted by the indoor electronic expansion valve 107 .

The controller 30 is configured to: obtain the opening of the indoor electronic expansion valve 107; and when the first preset condition is met, adjust according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval. The opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107 are adjusted based on the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval.

In some embodiments, the first preset condition includes that the opening of the indoor electronic expansion valve 107 is smaller than the first preset opening.

The outdoor heat exchanger 103 condenses the refrigerant. At this time, the air conditioning system 1 is in the cooling mode. When the air conditioning system 1 operates in the cooling mode, the controller 30 obtains the opening of the indoor electronic expansion valve 107 and determines whether the opening of the outdoor electronic expansion valve 104 is less than the first preset opening.

Illustratively, the opening of the indoor electronic expansion valve 107 that is smaller than the preset first opening includes: the indoor electronic expansion valve 107 in the indoor unit 20 in the running state in the air conditioning system 1 (such as the first indoor electronic expansion valve 1071 and the first indoor electronic expansion valve 107). The openings of the electronic expansion valves 1072) in the two chambers are both smaller than the first preset opening. In some embodiments, the first preset opening is smaller than the maximum opening of the indoor electronic expansion valve 107 . For example, the first preset opening may be 90 percent of the maximum opening of the indoor electronic expansion valve 107 .

The openings of the indoor electronic expansion valve 107 are all smaller than the first preset opening, indicating that the indoor electronic expansion valve 107 has room for adjustment. For example, the outdoor electronic expansion valve 107 can also be adjusted smaller. Correspondingly, the outdoor electronic expansion valve 104 also has corresponding space for adjustment. In this case, the controller 30 can adjust the opening of the outdoor electronic expansion valve 104 according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval, and adjust the opening of the outdoor electronic expansion valve 104 according to the exhaust gas flow rate of the compressor 102. The opening of the indoor electronic expansion valve 107 is adjusted based on the relationship between the heat and the target exhaust superheat range.

For example, the opening of the outdoor electronic expansion valve 104 can be expressed as EVO, the minimum opening of the outdoor electronic expansion valve 104 can be expressed as EVO _min , and the maximum opening of the outdoor electronic expansion valve 104 can be expressed as EVO _max ; the indoor electronic expansion valve 107 The opening of is expressed as EVI, the minimum opening of the indoor electronic expansion valve 107 is expressed as EVI _min , and the maximum opening of the indoor electronic expansion valve 107 is expressed as EVI _max .

In some embodiments, the controller 30 is configured to: if the subcooling degree of the outdoor heat exchanger 103 is greater than the upper limit of the first target subcooling degree interval, increase the opening of the outdoor electronic expansion valve 104; if the outdoor heat exchanger 103 If the subcooling degree of the heat exchanger 103 is less than the lower limit of the first subcooling degree interval, reduce the opening of the outdoor electronic expansion valve 104; if the subcooling degree of the outdoor heat exchanger 103 is greater than or equal to the first subcooling degree interval The lower limit value is less than or equal to the upper limit value of the first subcooling interval, and the opening of the outdoor electronic expansion valve 104 is controlled to remain unchanged.

For example, the degree of subcooling of the outdoor heat exchanger 103 can be expressed as ΔToSC, and the target degree of subcooling of the outdoor heat exchanger 103 can be expressed as ΔToSCo. Among them, the degree of subcooling ΔToSC of the outdoor heat exchanger 103=Tc-Te, Tc represents the saturation temperature corresponding to the pressure Pd measured by the compressor exhaust pressure sensor 114 and the compressor exhaust temperature sensor 115, and Te represents the saturation temperature measured by the compressor exhaust pressure sensor 114 and the compressor exhaust temperature sensor 115. A temperature sensor 113 measures the temperature of the refrigerant at the outlet of the outdoor heat exchanger 103.

The target subcooling degree ΔToSCo of the outdoor heat exchanger 103 may be different under working conditions of different ambient temperatures. In some embodiments, the target subcooling degree ΔToSCo of the outdoor heat exchanger 103=a×Ta+b, where a and b are constants, and Ta is the outdoor ambient temperature; for example, a≥0 (for example, 3≤a ≤30), b≤0 (for example, -2≤b≤0), 0℃≤ΔToSCo≤15℃.

Illustratively, the first target subcooling interval is related to the target subcooling degree ΔToSCo of the outdoor heat exchanger 103 . For example, the lower limit of the first target subcooling interval can be expressed as ΔToSCo-λ1, and the upper limit of the first target subcooling interval can be expressed as ΔToSCo+λ1, where λ1>0, for example, 0°C<λ1 <3℃. That is to say, the first target subcooling interval can be expressed as [ΔToSCo-λ1, ΔToSCo+λ1].

Therefore, when ΔToSC>ΔToSCo+λ1, it indicates that ΔToSC is too large, so EVO needs to be increased to reduce ΔToSC; when ΔToSC<ΔToSCo-λ1, it indicates that ΔToSC is too small, so EVO needs to be reduced to increase ΔToSC; and when When ΔToSCo-λ1≤ΔToSC≤ΔToSCo+λ1, ΔToSC is within the first target subcooling range, and the air conditioning system 1 is operating normally at this time, so there is no need to adjust EVO.

For example, each time the controller 30 adjusts (increases or decreases) the opening of the outdoor electronic expansion valve 104, the adjustment amount (increase or decrease) may be between 0.1% of the maximum opening of the outdoor electronic expansion valve 104. ~10% (for example, including 0.1% and/or 10%). For example, if the adjustment amount of the opening of the outdoor electronic expansion valve 104 is expressed as ΔEVO, then 0.1%×EVO _max ≤ ΔEVO ≤ 10%×EVO _max .

In some embodiments, the controller 30 is configured to: if the superheat degree of the compressor 102 is greater than the upper limit of the target exhaust superheat degree, increase the opening of the indoor electronic expansion valve 107; if the superheat degree of the compressor 102 is less than The lower limit of the target exhaust superheat degree reduces the opening of the indoor electronic expansion valve 107; if the superheat degree of the compressor 102 is greater than or equal to the lower limit of the target exhaust superheat range and less than or equal to the target exhaust superheat degree At the upper limit of the interval, the opening of the electronic expansion valve 107 in the control room remains unchanged.

For example, the exhaust gas superheat degree of the compressor 102 can be expressed as ΔTdSH, and the target exhaust gas superheat degree of the compressor 102 can be expressed as ΔTdSHo. Among them, the exhaust gas superheat degree ΔTdSH of the compressor 102 = Td - Tc, and Td represents the exhaust gas temperature of the compressor 102 measured by the compressor exhaust temperature sensor 115 .

For example, the target exhaust superheat range is related to the target exhaust superheat of the compressor 102, where the unit of the superheat is °C. For example, the lower limit of the target exhaust superheat range can be expressed as ΔTdSHo-δ, and the upper limit of the target exhaust superheat range can be expressed as ΔTdSHo+δ, where 20≤ΔTdSHo≤30; δ>0, for example, 0<δ<3, that is to say, the target exhaust superheat interval can be expressed as [ΔTdSHo-δ, ΔTdSHo+δ].

Therefore, when ΔTdSH > ΔTdSHo + δ, it indicates that ΔTdSH is too large, so EVI needs to be increased to reduce ΔTdSH; when ΔTdSH < ΔTdSHo-δ, it indicates that ΔTdSH is too small, so EVI needs to be reduced to increase ΔTdSH; and when When ΔToSCo-λ1≤ΔTdSH≤ΔToSCo+λ1, ΔTdSH is within the first target subcooling interval, and the air conditioning system 1 is operating normally at this time, so no EVI is required.

For example, the adjustment amount (increase or decrease) each time the controller 30 adjusts (increases or decreases) the opening of the indoor electronic expansion valve 107 may be between 0.1% of the maximum opening of the indoor electronic expansion valve 107 ~10%. For example, if the adjustment amount of the opening of the outdoor electronic expansion valve 104 is expressed as ΔEVO, then 0.1% EVI _max ≤ ΔEVO ≤ 10% EVI _max .

For example, the control process of the controller 30 when the first preset condition is met can be called control mode a. When the air conditioning system 1 is in the cooling mode, the controller 30 enters the control mode when the first preset condition is met. a. By adjusting the openings of the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104, the subcooling degree of the outdoor heat exchanger 103 is controlled to be within the first target subcooling degree interval, and the exhaust superheat degree of the compressor 102 is controlled to be within the target Within the exhaust superheat range, this can ensure that the refrigerant in the online liquid pipe 106 is in a two-phase state. Therefore, when the amount of refrigerant in the air conditioning system 1 is small, it can also ensure that the cooling capacity of the air conditioning system 1 is maintained at a good level. level, realizing the need for no additional refrigerant in the air conditioning system 1. At the same time, by adjusting the openings of the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104, stable operation of the air conditioning system 1 can also be ensured.

The control mode a will be described below with reference to Figure 5 .

Step 51: The indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 respectively operate at the current opening.

For example, when the air conditioning system 1 is running in the nth cycle, the opening of the indoor electronic expansion valve 107 can be expressed as EVI(n), and the opening of the outdoor electronic expansion valve can be expressed as EVO(n).

Step 52: Determine whether: ΔToSC-ΔToSCo>λ1 is satisfied.

If satisfied, it means that the subcooling degree ΔToSC of the outdoor heat exchanger 103 is greater than the upper limit of the first target subcooling degree ΔToSCo+λ1. In this case, EVO needs to be increased to reduce the subcooling degree of the outdoor heat exchanger 103. Make it be within the first target subcooling interval, therefore, step 521 can be performed; if not, continue to step 53.

Step 521: Determine whether EVO(n)<EVO _max is satisfied.

If it is satisfied, it indicates that the current opening EVO(n) of the outdoor electronic expansion valve 104 has not reached the maximum opening EVO _max of the outdoor electronic expansion valve 104, and there is still room for increase, and step 522 is continued; if it is not satisfied, it indicates that the outdoor electronic expansion valve 104 does not reach the maximum opening EVO max of the outdoor electronic expansion valve 104. The valve 104 has currently reached the maximum opening EVO _max and there is no room for increase. At this time, step 523 is executed.

Step 522, EVO(n+1)=EVO(n)+ΔEVO ₁ .

When the air conditioning system 1 enters the next cycle (ie, the n+1th cycle), the opening of the outdoor electronic expansion valve 104 will be increased, for example, EVO(n+1)=EVO(n)+ΔEVO ₁ , where ΔEVO ₁ is the increasing value of the opening of the outdoor electronic expansion valve 104.

Step 523, EVO(n+1)=EVO _max .

When the air conditioning system 1 enters the n+1th cycle, the opening EVO(n+1) of the outdoor electronic expansion valve 104 is maintained at EVO _max .

Step 53: Determine whether: ΔToSC-ΔToSCo<-λ1 is satisfied.

If satisfied, it means that the subcooling degree ΔToSC of the outdoor heat exchanger 103 is less than the lower limit value ΔToSCo-λ1 of the first target subcooling degree. In this case, it is necessary to reduce the opening EVO of the outdoor electronic expansion valve 104 to increase the subcooling degree of the outdoor heat exchanger 103 so that it is within the first target subcooling degree interval. Therefore, step 531 can be performed; if If not satisfied, continue to step 54.

Step 531, determine whether: EVO(n)>EVO _min is satisfied.

If it is satisfied, it indicates that the current opening EVO(n) of the outdoor electronic expansion valve 104 has not reached the minimum opening EVO _min of the outdoor electronic expansion valve 104 and there is still room for reduction, and step 532 is continued; if it is not satisfied, it indicates that the outdoor electronic expansion valve 104 has less opening EVO min . The valve 104 has currently reached the minimum opening EVO _min and there is no room for reduction. Step 533 is continued.

Step 532, EVO(n+1)=EVO(n)-ΔEVO ₂ .

In the n+1th cycle, the opening of the outdoor electronic expansion valve 104 is reduced, for example, EVO(n+1)=EVO(n)-ΔEVO ₂ , where ΔEVO ₂ is the decrease in the opening of the outdoor electronic expansion valve 104 . Small value.

Step 533, EVO(n+1)=EVO _min .

In the n+1th cycle, the opening EVO(n+1) of the outdoor electronic expansion valve 104 is maintained at EVO _min .

Step 54, EVO(n+1)=EVO(n).

In this case, it indicates that the subcooling degree of the outdoor heat exchanger 103 is within the first target subcooling degree interval, that is, it satisfies: λ1-≤ΔToSC-ΔToSCo≤λ1. Therefore, in the n+1th period, the outdoor electrons can be controlled The expansion valve 104 maintains the opening degree of the previous cycle (ie, the nth cycle), that is, EVO(n+1)=EVO(n).

Step 55: Determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

If satisfied, it means that the exhaust gas superheat degree ΔTdSH of the compressor 102 is greater than the upper limit value ΔTdSHo+δ of the target exhaust gas superheat degree. In this case, it is necessary to increase the opening EVI of the indoor electronic expansion valve 107 to reduce the exhaust superheat degree ΔTdSH of the compressor 102. Therefore, step 551 can be performed; if not satisfied, step 56 continues.

Step 551: Determine whether EVI(n)<EVI _max is satisfied.

If it is satisfied, it indicates that the current opening EVI(n) of the indoor electronic expansion valve 107 has not reached the maximum opening EVI _max of the indoor electronic expansion valve 107 and there is room for increase, and step 552 is continued; if it is not satisfied, it indicates that the indoor electronic expansion valve 107 has room for increase. The expansion valve 107 has currently reached the maximum opening EVI _max and there is no room for increase. Step 553 is continued.

Step 552, EVI(n+1)=EVI(n)+ΔEVI ₁ .

In the n+1th cycle, the opening of the indoor electronic expansion valve 107 is increased, for example, EVI(n+1)=EVI(n)+ _ΔEVI1 , where _ΔEVI1 is the increase in the opening of the indoor electronic expansion valve 107. Large value.

Step 553, EVI(n+1)= _EVImax .

In the n+1th cycle, the opening EVI(n+1) of the indoor electronic expansion valve 107 is maintained at EVI _max .

Step 56: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

If satisfied, it means that the exhaust superheat degree of the compressor 102 is less than the lower limit value ΔTdSHo-δ of the ΔTdSH target exhaust superheat degree interval. In this case, it is necessary to reduce the opening EVO of the indoor electronic expansion valve 107 to increase the exhaust superheat degree ΔTdSH of the compressor 102. Therefore, step 561 can be executed; if not satisfied, step 57 continues.

Step 561, determine whether it is satisfied: EVI(n)>EVI _min .

If it is satisfied, it indicates that the current opening EVO(n) of the indoor electronic expansion valve 107 has not reached the minimum opening of the indoor electronic expansion valve 107, and there is still room for reduction, and step 562 is continued; if it is not satisfied, it indicates that the indoor electronic expansion valve 107 The minimum opening EVI _min has currently been reached, and there is no room for reduction. Step 563 continues.

Step 562, EVI(n+1)=EVI(n) _-ΔEVI2 .

Therefore, in the n+1th cycle, the opening of the indoor electronic expansion valve 107 is reduced, for example, EVI(n+1)=EVI(n)-ΔEVI ₂ , where ΔEVI ₂ is the ratio of the opening of the indoor electronic expansion valve 107 Decrease the value.

Step 563, EVI(n+1)= _EVImin .

In the n+1th cycle, the opening EVI(n+1) of the indoor electronic expansion valve 107 is maintained at EVI _min .

Step 57, EVI(n+1)=EVI(n).

When the exhaust superheat degree of the compressor 102 is within the target exhaust superheat degree range, that is, when -δ≤ΔTdSH-ΔTdSHo≤δ is satisfied, therefore, at time n+1, the indoor electronic expansion valve 107 can be controlled to maintain the nth period. The opening EVI(n) operates, that is, EVI(n+1)=EVI(n).

The controller 30 is configured to: when the first preset condition is not met, adjust the opening of the outdoor electronic expansion valve 104 and the indoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval. The opening of the expansion valve 107.

It should be noted that when the exhaust superheat degree of the compressor 102 is not within the target exhaust superheat degree range, it indicates that the current operation of the compressor 102 is unstable and the air conditioning system 1 may malfunction. Therefore, it is necessary to adjust the outdoor electronic expansion valve 104 and The indoor electronic expansion valve 107 is adjusted to control the exhaust superheat of the compressor 102 to remain within the target exhaust superheat range, thereby ensuring the stable operation of the air conditioning system 1 .

In some embodiments, the controller 30 is configured to: if the exhaust superheat of the compressor 102 is greater than the upper limit of the target exhaust superheat interval, increase the opening of the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 If the exhaust superheat of the compressor 102 is less than the lower limit of the target exhaust superheat interval, reduce the opening of the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107; if the exhaust of the compressor 102 exceeds When the heat is within the target exhaust superheat range, the outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 are controlled to maintain their current openings.

For example, the controller 30 may first adjust the opening of the outdoor electronic expansion valve 104 and then adjust the opening of the indoor electronic expansion valve 107 based on the relationship between the exhaust superheat of the compressor 102 and the target exhaust superheat interval. Among them, the controller 30 adjusts the opening of the indoor electronic expansion valve 107 according to the relationship between the exhaust gas superheat degree of the compressor 102 and the target exhaust superheat degree interval. In some of the above embodiments, the controller 30 adjusts the opening of the indoor electronic expansion valve 107 according to the exhaust gas superheat degree of the compressor 102. The relationship between the superheat degree and the target exhaust superheat degree interval is similar to the process of adjusting the outdoor electronic expansion valve 104 and will not be described again here.

For example, when the first preset condition is not met, the control process of the controller 30 can be called control mode b. When the first preset condition is not met, it indicates that there are one or more indoor rooms in the operating state in the air conditioning system 1 The opening of the indoor electronic expansion valve 107 in the machine is greater than or equal to the first preset opening. In this case, the indoor electronic expansion valve 107 is close to the fully open state and is in an uncontrollable state. Therefore, the stability of the air conditioning system 1 will be affected. affected. At this time, the controller 30 will enter the control mode b, and adjust the opening of the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 so that the exhaust superheat of the compressor 102 is within the target exhaust superheat range to ensure that The stable operation of the compressor 102 ensures the stable operation of the air conditioning system 1 .

The operation process of control mode b will be described below with reference to Figure 6 .

Step 61: The indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 operate at the current opening degree respectively.

It is similar to step 51 in the above embodiment and will not be described again here.

Step 62: Determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

It is similar to step 55 in the above embodiment and will not be described again here. If satisfied, proceed to step 621; if not satisfied, proceed to step 63.

Step 621, determine whether the condition is met: EVO(n)<EVO _max .

It is similar to step 521 in the above embodiment and will not be described again here. If satisfied, proceed to step 622; if not satisfied, proceed to step 623.

Step 622, EVO(n+1)=EVO(n)+ΔEVO ₁ .

Step 623, EVO(n+1)=EVO _max .

Step 63: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

It is similar to step 56 in the above embodiment and will not be described again here. If satisfied, proceed to step 631; if not satisfied, proceed to step 64.

Step 631, determine whether: EVO(n)>EVO _min is satisfied.

It is similar to step 531 in the above embodiment and will not be described again here. If satisfied, proceed to step 632; if not satisfied, proceed to step 632.

Step 632, EVO(n+1)=EVO(n)-ΔEVO ₂ .

Step 633, EVO(n+1)=EVO _min .

Step 64, EVO(n+1)=EVO(n).

Step 65: Determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

It is similar to step 55 in the above embodiment and will not be described again here. If satisfied, proceed to step 651; if not satisfied, proceed to step 66.

Step 651: Determine whether EVI(n)<EVI _max is satisfied.

It is similar to step 551 in the above embodiment and will not be described again here. If satisfied, execute step 652; if not satisfied, execute step 653.

Step 652, EVI(n+1)=EVI(n)+ΔEVI ₁ .

Step 653, EVI(n+1)= _EVImax .

Step 66: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

It is similar to step 56 in the above embodiment and will not be described again here. If satisfied, proceed to step 651; if not satisfied, proceed to step 66.

Step 661: Determine whether EVI(n)>EVI _min is satisfied.

It is similar to step 561 in the above embodiment and will not be described again here. If satisfied, execute step 662; if not satisfied, execute step 663.

Step 662, EVI(n+1)=EVI(n) _-ΔEVI2 .

Step 663, EVI(n+1)= _EVImin .

Step 67, EVI(n+1)=EVI(n).

In some embodiments, the controller 30 is configured to: when the first preset condition is met and the second preset condition is met, based on the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval , adjust the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107. When the first preset condition is satisfied and the second preset condition is not satisfied, the opening of the outdoor electronic expansion valve 104 is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval. , and adjust the opening of the indoor electronic expansion valve 107 according to the relationship between the exhaust gas superheat degree of the compressor 102 and the target exhaust superheat degree interval.

In some embodiments, the second preset condition includes: the opening of the target indoor electronic expansion valve in the target indoor unit is greater than or equal to the second preset opening, and the superheat degree of the target indoor heat exchanger in the target indoor unit is greater than or equal to the second preset opening. or equal to the target superheat degree, and the exhaust gas superheat degree of the compressor 102 is greater than or equal to the upper limit of the target exhaust superheat degree interval.

For example, the target indoor unit is one indoor unit 20 among the plurality of indoor units 20 . Therefore, the target indoor electronic expansion valve is one of the plurality of indoor electronic expansion valves 107 , for example, the target indoor electronic expansion valve is the indoor electronic expansion valve 1071 or the indoor electronic expansion valve 1072 ; the target heat exchanger is a plurality of indoor heat exchangers 108 One of them, for example, the target indoor heat exchanger is the indoor heat exchanger 1081 or the indoor heat exchanger 1082.

It should be noted that in the cooling mode, the indoor heat exchanger 108 is used as an evaporator. If the opening EVI of the indoor electronic expansion valve 107 on the evaporator side is greater than the second preset opening, that is, when it is close to fully open, the indoor heat exchanger 108 is used as an evaporator. The superheat of the heater 108 will be too large, and when the exhaust superheat of the compressor 102 is greater than the upper limit of the target exhaust superheat interval, it indicates that the superheat of at least one indoor heat exchanger 108 is uncontrollable, so This will cause the compressor 102 to not operate stably.

Taking the control mode a and the control mode b in the above embodiment as an example, that is, after the air conditioning system 1 executes the control mode a, it still needs to determine whether the second preset condition is met. If the second preset condition is met, the air conditioning system 1 1 executes control mode a again. If the second preset condition is not met, the air conditioning system 1 enters control mode b.

In some embodiments, the second preset opening is greater than the first preset opening. For example, the second preset opening may be 97% of the maximum opening value of the indoor electronic expansion valve 107 .

For example, the superheat degree of the target indoor heat exchanger can be expressed as ΔSH, where ΔSH=Tg-Tl, Tg represents the temperature of the online air pipe 109 measured by the third temperature sensor 117, and Tl represents the temperature measured by the second temperature sensor 116. The temperature of the online liquid pipe 106 is obtained.

The control process of the controller 30 when the air conditioning system 1 is in the cooling mode will be described below with reference to FIG. 7 .

Step 71: Obtain the opening EVI of the indoor electronic expansion valve 107.

For example, at time n, the opening degrees of the plurality of indoor electronic expansion valves 107 are obtained as EVI(n).

Step 72: Determine whether the first preset condition is met.

For example, it is determined whether the opening EVI(n) of the indoor electronic expansion valve 107 is less than 90%×EVI _max , where 90%×EVI _max represents the first preset opening. If satisfied, proceed to step 73; if not satisfied, proceed to step 75.

Step 73: Run control mode a.

Perform step 51 to step 57 in the above embodiment.

Step 74: Determine whether the second preset condition is met.

For example, it is determined whether the superheat of the target indoor heat exchanger is greater than the target superheat, whether the opening of the target indoor electronic expansion valve is greater than the first preset opening, and the exhaust superheat of the compressor 102 exceeds the target exhaust superheat. The upper limit of the interval is to determine whether the conditions are met: ΔSH>e, at least one EVI(n)>97%×EVI _max and ΔTdSH-ΔTdSHo>δ+d. Among them, d>0 (for example, 5°C<d<10°C), e>0 (for example, 2°C<e<5°C). If satisfied, proceed to step 73; if not satisfied, proceed to step 75.

Step 75: Run control mode b.

Perform step 61 to step 67 in the above embodiment.

In summary, when the air conditioning system 1 provided by some embodiments of the present disclosure is in the cooling mode, by determining whether the first preset condition and the second preset condition are met, the air conditioning system 1 can obtain the information about the indoor heat exchanger 108 and the compressor 102 working state, and adjust the outdoor electronic expansion valve 104 and the indoor electronic expansion according to the relationship between the exhaust superheat degree of the compressor 102 and the target superheat degree interval or the relationship between the subcooling degree of the outdoor heat exchanger 103 and the target subcooling degree. The valve 107 is configured so that the subcooling degree of the outdoor heat exchanger 103 is within the first target subcooling degree range, and the exhaust gas superheat degree of the compressor 102 is within the target exhaust superheat degree range, thereby realizing the refrigerant in the air conditioning system 1 No additional addition is required, and the stable operation of the air conditioning system 1 can be ensured and the reliability of the air conditioning system 1 can be improved.

In some embodiments, the compressor 102 compresses the refrigerant and discharges the compressed refrigerant, the indoor heat exchanger 108 condenses the compressed refrigerant, and the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 sequentially condense the indoor heat exchanger. 108 to adjust the amount of condensed refrigerant, and the outdoor heat exchanger 103 evaporates the refrigerant adjusted by the outdoor electronic expansion valve 104. The controller 30 is also configured to: obtain the opening of the outdoor electronic expansion valve 104; when the third preset condition is met, based on the relationship between the subcooling degree of the indoor heat exchanger 108 and the second target subcooling degree interval, The opening of the indoor electronic expansion valve 107 is adjusted, and the opening of the outdoor electronic expansion valve 104 is adjusted based on the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval.

In some embodiments, the third preset condition includes that the opening of the outdoor electronic expansion valve 104 is less than the third preset opening.

When the air conditioning system 1 works in the heating mode, the outdoor heat exchanger 103 evaporates the refrigerant, the controller 30 obtains the opening of the outdoor electronic expansion valve 104, and determines whether the opening of the outdoor electronic expansion valve 107 is smaller than the third preset value. opening.

In some embodiments, the third preset opening is smaller than the maximum opening of the outdoor electronic expansion valve 104 . For example, the third preset opening may be 90% of the maximum opening of the outdoor electronic expansion valve 104 .

The opening of the outdoor electronic expansion valve 104 is smaller than the third preset opening, indicating that there is still room for adjustment of the opening of the outdoor electronic expansion valve 104 . In this case, the controller 30 can adjust the opening of the indoor electronic expansion valve 107 according to the relationship between the subcooling degree of the indoor heat exchanger 108 and the second target subcooling degree interval, and adjust the opening of the indoor electronic expansion valve 107 according to the exhaust gas flow rate of the compressor 102. The opening of the outdoor electronic expansion valve 104 is adjusted based on the relationship between the heat degree and the target exhaust superheat range.

For example, the degree of subcooling of the indoor heat exchanger 108 can be expressed as ΔTiSC, and the target degree of subcooling of the indoor heat exchanger 108 can be expressed as ΔTiSCo. Among them, the subcooling degree ΔTiSC of the indoor heat exchanger 108=Tc-Tl. For example, the target subcooling degree ΔTiSCo of the indoor heat exchanger 108 can also be set differently according to the air cooling ratio, where the air cooling ratio is used to indicate the ratio between the air volume and the capacity of the indoor unit 20 . For example, when the air cooling ratio is large, the air outlet temperature of the indoor unit is low. At this time, in order to prevent cold air from coming out, the target subcooling degree ΔTiSCo can be set smaller. For example, ΔTiSCo can be set at 5℃-8℃; When the air cooling ratio is small, the target subcooling degree ΔTiSCo can be set larger. For example, ΔTiSCo can be set at 12°C-20°C.

Illustratively, the second target subcooling interval is related to the target subcooling degree ΔTiSCo of the indoor heat exchanger 108 . For example, the lower limit of the second target subcooling interval can be expressed as ΔTiSCo-λ2, and the upper limit of the second target subcooling interval can be expressed as ΔTiSCo+λ2, where λ2 can be the same as λ1, that is, The second target subcooling interval can be expressed as [ΔTiSCo-λ2, ΔTiSCo+λ2].

It should be noted that when the air conditioning system 1 operates in the heating mode, the indoor heat exchanger 108 operates as a condenser. By adjusting the opening of the indoor electronic expansion valve 107, the degree of subcooling of the indoor heat exchanger 108 can be controlled. The outdoor heat exchanger 103 operates as an evaporator. By adjusting the opening of the outdoor electronic expansion valve 104, the superheat of the outdoor heat exchanger 103 and the exhaust superheat of the compressor 102 can be adjusted.

In some embodiments, the controller 30 is configured to: if the subcooling degree of the indoor heat exchanger 108 is greater than the upper limit of the second target subcooling degree interval, increase the opening of the indoor electronic expansion valve 107; If the subcooling degree of the heater 108 is less than the lower limit of the second target subcooling range, reduce the opening of the indoor electronic expansion valve 107; if the subcooling degree of the indoor heat exchanger 108 is greater than or equal to the second target subcooling degree The lower limit value of the interval is less than or equal to the upper limit value of the second target subcooling interval, and the opening of the electronic expansion valve 107 in the control room remains unchanged.

That is, when ΔTiSC>ΔTiSCo+λ2, it indicates that the degree of subcooling ΔTiSC of the indoor heat exchanger 108 is too large, so EVI needs to be increased to reduce ΔTiSC; when ΔTiSC<ΔTiSCo-λ2, it indicates that the degree of subcooling of the indoor heat exchanger 108 is too large. The degree ΔTiSC is too small, so EVI needs to be reduced to increase ΔTiSC; and when ΔTiSCo-λ2≤ΔTiSC≤ΔTiSCo+λ2, ΔTiSC is within the second target subcooling range, and the air conditioning system 1 is operating normally at this time, so no adjustment is required EVI.

In some embodiments, the controller 30 is configured to: if the superheat degree of the compressor 102 is greater than the upper limit of the target exhaust superheat degree, increase the opening of the outdoor electronic expansion valve 104; if the superheat degree of the compressor 102 is less than The lower limit of the target exhaust superheat degree reduces the opening of the outdoor electronic expansion valve 104; if the superheat degree of the compressor 102 is greater than or equal to the lower limit of the target exhaust superheat range and less than or equal to the target exhaust superheat degree At the upper limit of the interval, the opening of the outdoor electronic expansion valve 104 is controlled to remain unchanged.

For example, the control process of the controller 30 when the third preset condition is met can be called control mode c. When the air conditioning system 1 is in the heating mode, when the third preset condition is met, the controller 30 enters the control mode. In mode c, by determining whether the opening of the outdoor electronic expansion valve 104 is smaller than the third preset opening, the working status of the outdoor electronic expansion valve 104 can be obtained. When the opening of the outdoor electronic expansion valve 104 is less than the third preset opening, it means that the air conditioning system 1 is operating stably. By adjusting the openings of the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104, the process of the indoor heat exchanger 108 can be controlled. The cooling degree is within the second target subcooling degree interval, and the exhaust gas superheat degree of the compressor 102 is within the target exhaust superheat degree interval. Therefore, even when the amount of refrigerant in the air conditioning system 1 is small, the normal operation of the air conditioning system 1 can be ensured.

The operation process of control mode c will be described below with reference to Figure 8.

Step 81: The indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 respectively operate at the current opening.

It is similar to step 51 in the above embodiment and will not be described again here.

Step 82, determine whether: ΔTiSC-ΔTiSCo>λ2 is satisfied.

If satisfied, it means that the subcooling degree ΔTiSC of the indoor heat exchanger 108 is greater than the upper limit of the second target subcooling degree ΔTiSCo+λ2. In this case, EVI needs to be increased to reduce the subcooling degree of the indoor heat exchanger 108. Make it be within the second target subcooling interval, therefore, execute step 821; if not, continue to execute step 83.

Step 821, determine whether EVI(n)<EVI _max is satisfied.

It is similar to step 551 in the above embodiment and will not be described again here. If satisfied, execute step 822; if not satisfied, execute step 823.

Step 822, EVI(n+1)=EVI(n)+ΔEVI ₁ .

Step 823, EVI(n+1)= _EVImax .

Step 83, determine whether: ΔTiSC-ΔTiSCo<-λ2 is satisfied.

If satisfied, it means that the subcooling degree ΔTiSC of the indoor heat exchanger 108 is less than the lower limit value ΔTiSCo-λ2 of the second target subcooling degree. In this case, the EVI needs to be reduced to increase the subcooling degree of the indoor heat exchanger 108 so that it is within the second target subcooling degree interval. Therefore, step 831 is executed; if not satisfied, step 84 is executed.

Step 831, determine whether it is satisfied: EVI(n)>EVI _min .

It is similar to step 561 in the above embodiment and will not be described again here. If satisfied, execute step 832; if not satisfied, execute step 833.

Step 832, EVI(n+1)=EVI(n) _-ΔEVI2 .

Step 833, EVI(n+1)= _EVImin .

Step 84, EVI(n+1)=EVI(n).

Step 85, determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

It is similar to step 55 in the above embodiment and will not be described again here. If satisfied, execute step 851; if not satisfied, execute step 86.

Step 851, determine whether: EVO(n)<EVO _max is satisfied.

It is similar to step 521 in the above embodiment and will not be described again here. If satisfied, execute step 852; if not satisfied, execute step 853.

Step 852, EVO(n+1)=EVO(n)+ΔEVO ₁ .

Step 853, EVO(n+1)=EVO _max .

Step 86: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

It is similar to step 56 in the above embodiment and will not be described again here. If satisfied, execute step 861; if not satisfied, execute step 87.

Step 861, determine whether: EVO(n)>EVO _min is satisfied.

It is similar to step 531 in the above embodiment and will not be described again here. If satisfied, execute step 862; if not satisfied, execute step 863.

Step 862, EVO(n+1)=EVO(n)-ΔEVO ₂ .

Step 863, EVO(n+1)= _EVOmin .

Step 87, EVO(n+1)=EVO(n).

In some embodiments, the controller 30 is further configured to: when the third preset condition is not met, adjust the outdoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval. 104 and the opening of the indoor electronic expansion valve 107.

For example, the controller 30 may first adjust the opening of the indoor electronic expansion valve 107 and then adjust the opening of the outdoor electronic expansion valve 107 based on the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval. When the third preset condition is not met, the control process of the controller 30 is similar to the control process when the first preset condition is not met in the above embodiment, and will not be described again here.

For example, the control process of the controller 30 when the third preset condition is not met can be called control mode d. When the air conditioning system 1 is in the heating mode, and when the third preset condition is not met, it indicates that the outdoor The electronic expansion valve 104 is close to fully open and is in an uncontrollable state, and the stability of the air conditioning system 1 is affected. At this time, the controller 30 will enter the control mode d, and adjust the openings of the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 so that the exhaust superheat of the compressor 102 is within the target superheat range to ensure compression. The temperature of the machine 102 is maintained, thereby ensuring the stable operation of the air conditioning system 1.

The operation process of control mode d will be described below with reference to Figure 9. As shown in Figure 9, control mode d includes steps 91 to 97. Among them, steps 92 to 94 are similar to steps 65 to 67 in the above embodiment, and steps 95 to 97 are similar to steps 62 to 64 in the above embodiment.

Step 91: The indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 respectively operate at the current opening.

Step 92, determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

If satisfied, proceed to step 921; if not satisfied, proceed to step 93.

Step 921, determine whether EVI(n)<EVI _max is satisfied.

If satisfied, execute step 922; if not satisfied, execute step 923.

Step 922, EVI(n+1)=EVI(n)+ΔEVI ₁ .

Step 923, EVI(n+1)= _EVImax .

Step 93: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

If satisfied, continue to execute step 931; if not satisfied, continue to execute step 94.

Step 931, determine whether it is satisfied: EVI(n)>EVI _min .

If satisfied, execute step 932; if not satisfied, execute step 933.

Step 932, EVI(n+1)=EVI(n) _-ΔEVI2 .

Step 933, EVI(n+1)= _EVImin .

Step 94, EVI(n+1)=EVI(n).

Step 95: Determine whether: ΔTdSH-ΔTdSHo>δ is satisfied.

If satisfied, execute step 951; if not satisfied, proceed to step 96.

Step 951: Determine whether EVO(n)<EVO _max is satisfied.

If satisfied, execute step 952; if not satisfied, execute step 953.

Step 952, EVO(n+1)=EVO(n)+ΔEVO ₁ .

Step 953, EVO(n+1)=EVO _max .

Step 96: Determine whether: ΔTdSH-ΔTdSHo<-δ is satisfied.

If satisfied, execute step 961; if not satisfied, execute step 97.

Step 961, determine whether: EVO(n)>EVO _min is satisfied.

If satisfied, execute step 962; if not satisfied, execute step 963.

Step 962, EVO(n+1)=EVO(n)-ΔEVO ₂ .

Step 963, EVO(n+1)= _EVOmin .

Step 97, EVO(n+1)=EVO(n).

In some embodiments, the controller 30 is configured to: when the third preset condition is met and the fourth preset condition is met, according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval , adjust the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107. When the third preset condition is met and the fourth preset condition is not met, the opening of the indoor electronic expansion valve 107 is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger 108 and the second target subcooling degree interval. , and adjust the opening of the outdoor electronic expansion valve 104 according to the relationship between the exhaust gas superheat degree of the compressor 102 and the target exhaust superheat degree interval.

In some embodiments, the fourth preset condition includes: the opening of the outdoor electronic expansion valve 104 is greater than or equal to the fourth preset opening, and the exhaust superheat of the compressor 102 is greater than or equal to the target exhaust superheat interval. Upper limit.

It should be noted that in the heating mode, the outdoor heat exchanger 103 is used as an evaporator. If the opening EVO of the outdoor electronic expansion valve 104 on the evaporation side is greater than the fourth preset opening, at this time, the outdoor electronic expansion valve 104 It is in a nearly fully open state and the exhaust superheat of compressor 102 exceeds the upper limit of the target exhaust superheat. This means that compressor 102 in air conditioning system 1 is uncontrollable and the operation of air conditioning system 1 is unstable and requires outdoor electronic expansion. The valve 104 and the indoor unit electronic expansion valve 107 are adjusted to ensure the stable operation of the air conditioning system 1.

Taking the control mode c and the control mode d in the above embodiment as an example, that is, after the air conditioning system 1 executes the control mode c, it still needs to determine whether the fourth preset condition is met. If the fourth preset condition is met, the air conditioning system 1 1 executes control mode c again. If the fourth preset condition is not met, the air conditioning system 1 enters control mode d.

In some embodiments, the fourth preset opening is greater than the third preset opening. For example, the fourth preset opening may be 95% of the maximum opening value of the outdoor electronic expansion valve.

In some embodiments, the first preset opening, the second preset opening, the third preset opening and the fourth preset opening can be obtained through a large number of tests.

The following describes the control process of the controller 30 when the air conditioning system 1 is in the heating mode with reference to FIG. 10 .

Step 101: Obtain the opening EVO of the outdoor electronic expansion valve 104.

Step 102: Determine whether the third preset condition is met.

For example, it is judged whether the opening degree EVO(n) of the outdoor electronic expansion valve 104 is less than 90%×EVO _max , that is, it is judged that the condition is met: EVO(n)<90%×EVO _max , where 90%×EVO _max represents the third Preset opening. If satisfied, proceed to step 103; if not satisfied, proceed to step 105.

Step 103: Run control mode c.

Perform step 81 to step 87 in the above embodiment.

Step 104: Determine whether the fourth preset condition is met.

For example, it is determined that the opening of the outdoor electronic expansion valve is greater than the fourth preset opening, and the exhaust superheat of the compressor 102 is greater than the upper limit of the target exhaust superheat, that is, it is determined whether the condition is met: EVO(n)&gt; 95%×EVO _max and ΔTdSH-ΔTdSHo>δ+d. If satisfied, proceed to step 103; if not satisfied, proceed to step 105.

Step 105, run control mode d.

Perform step 91 to step 97 in the above embodiment.

In some embodiments, as shown in FIG. 11 , the air conditioning system 1 further includes a plurality of indoor units 20 (such as three indoor units 30 ) and a plurality of branch pipes 40 (such as four branch pipes 40 ), wherein the four Each branch pipe 40 may include two liquid phase branch pipes 41 and two gas phase branch pipes 42 . As shown in FIG. 11 , the direction from X to The second direction may be, for example, the direction from front (Y) to back (Y'). Among them, the two liquid phase branch pipes 41 are respectively located on one side of the indoor unit 20 (such as the Y side), and the two gas phase branch pipes 42 are respectively located on the other side of the indoor unit 20 (such as the Y' side).

For example, as shown in FIG. 11 , the liquid phase branch pipe 41 may include a first flow pipe 411 and two second flow pipes 412 , and one end of the two second flow pipes 412 may be connected to the first flow pipe 411 respectively. of the same end. Correspondingly, the two gas phase branch pipes 42 may include a third flow pipe 421 and two fourth flow pipes 422, and one ends of the two fourth flow pipes 422 may be connected to the same end of the third flow pipe 421 respectively.

Continuing to refer to Figure 11, when connecting the outdoor electronic expansion valve 104 and the three indoor units 20, the end of the first flow pipe 411 of the liquid phase branch pipe 41 located on the X side away from the second flow pipe 412 can be connected to the outdoor electronic expansion valve. 104 connection, which can be directly connected or connected through the extension of refrigerant pipe (such as steel pipe or aluminum pipe). One end of the second flow pipe 412 of the X-side liquid phase branch pipe 41 away from the first flow pipe can be connected to one end (such as the front end) of the first indoor electronic expansion valve 1071, and the other second flow pipe 412 can be connected to the X' side The first flow pipe 411 of the liquid phase branch pipe 41 is connected, and the two second flow pipes 412 of the X' side liquid phase branch pipe 41 can be connected to one end of the second indoor electronic expansion valve 1072 and the third indoor electronic expansion valve 1073 respectively. The outdoor electronic expansion valve 104 is connected to the three indoor units 20 respectively.

Continuing to refer to Figure 11, when connecting the four-way valve 111 with the three indoor units 20, the end of the third flow pipe 421 of the gas phase branch pipe 42 located on the X side away from the fourth flow pipe 422 can be connected to one end of the four-way valve 111. The connection can be directly connected or connected through the extension of the refrigerant pipe. One end of the fourth flow pipe 422 of the X-side gas phase branch pipe 42 away from the third flow pipe 421 can be connected to the rear end of the first indoor heat exchanger 1081 of the X-side indoor unit, and the other fourth flow pipe 422 can be connected to The third flow pipe 421 of the X' side gas phase branch pipe 42 is connected correspondingly, and the two fourth flow pipes 422 of the X' side gas phase branch pipe 42 can be connected with the second indoor heat exchanger 1082 and the third indoor heat exchanger respectively. The rear ends of 1083 are connected respectively, thereby realizing the communication between the four-way valve 111 and the three indoor units 20 respectively.

In some embodiments, when the air conditioning system 1 is in cooling mode, when the refrigerant charge is small, or when the gas phase refrigerant cannot be completely converted into liquid phase refrigerant, the outdoor heat exchanger 103 flows to the liquid phase. The refrigerant in the branch pipe 41 is generally a gas-liquid two-phase refrigerant. When the gas-liquid two-phase refrigerant is diverted from the liquid phase branch pipe 41 to the plurality of indoor units 20, due to the differences in the installation heights of the plurality of indoor units 20 and the lengths of the refrigerant pipes connected to the outdoor units 10, the gas-liquid two-phase After the refrigerant is diverted through one or more liquid phase branch pipes 41, the liquid phase refrigerant and the gas phase refrigerant are gradually separated, and a large amount of the gas phase refrigerant will be concentrated in the indoor heat exchanger 108 of one or more indoor units 20, causing the flow through The amount of refrigerant in this part of the indoor heat exchanger 108 is greatly reduced, resulting in a sharp decrease in the cooling capacity of this part of the indoor unit 20 .

To this end, as shown in FIG. 11 , the subcooling degree of the outdoor heat exchanger 103 can be obtained from the temperature measured by the first temperature sensor 113 . In some embodiments, when the subcooling degree of the outdoor heat exchanger 103 is greater than the preset subcooling degree, for example, the preset subcooling degree can be any temperature between 6°C and 15°C, the outdoor heat exchanger 103 flows out The refrigerants are all supercooled liquid phase refrigerants. In this case, by controlling the opening of the outdoor electronic expansion valve 104 and combining it with the temperature of the refrigerant in the refrigerant pipeline between the outdoor heat exchanger 103 and the outdoor electronic expansion valve 104 detected by the first temperature sensor 113, So that the refrigerant flowing out of the outdoor heat exchanger 103 is all supercooled liquid phase refrigerant.

In some embodiments, when the degree of subcooling of the refrigerant flowing out of the outdoor heat exchanger 103 is always greater than or equal to the preset degree of subcooling, it means that the refrigerant flowing through the outdoor heat exchanger 103 can fully release heat and be completely condensed into Liquid phase supercooling refrigerant. In this way, the opening of the outdoor electronic expansion valve 104 can be kept adjusted and maintained at the maximum value, which is beneficial to increasing the circulation speed of the refrigerant.

In other examples, when the subcooling degree of the refrigerant flowing out of the outdoor heat exchanger 103 is less than the preset subcooling degree, in order to avoid that the refrigerant flowing through the outdoor heat exchanger 103 cannot be fully condensed into liquid refrigerant. The opening of the outdoor electronic expansion valve can be adjusted smaller until the subcooling degree of the refrigerant flowing out of the outdoor heat exchanger 103 is equal to or slightly greater than the preset subcooling degree. That is, the flow speed of the refrigerant can be reduced so that all the refrigerant flowing out of the outdoor heat exchanger 103 is liquid phase refrigerant.

However, in some embodiments, even if the opening of the outdoor electronic expansion valve 104 is adjusted to the minimum, the subcooling degree of the outdoor heat exchanger 103 will still be less than the preset subcooling degree. At this time, the outdoor electronic expansion valve 104 is always kept At the minimum opening, the refrigerant flowing from the outdoor heat exchanger 103 to the liquid-phase branch pipe 41 is still a gas-liquid two-phase refrigerant; or, as can be seen from some of the above embodiments, the air conditioning system 1 needs to ensure that the online liquid pipe 106 is not required when no additional refrigerant is required. The refrigerant is a gas-liquid two-phase refrigerant. In this way, the amount of refrigerant flowing through each indoor heat exchanger 108 is still uneven, causing the cooling capacity of this part of the indoor unit 20 to drop sharply.

In order to solve the above problem, as shown in FIG. 12A , in some embodiments, the air conditioning system 1 further includes at least one flow mixing member 50 , and the first flow pipe 411 may include at least one flow mixing member 50 , and the mixing member 50 has a plurality of first flow mixing members 50 . Through holes (not shown in FIG. 12A ), a plurality of first through holes are used to connect both ends of the first flow tube 411 .

When the air conditioning system 1 is in cooling mode, if the refrigerant flowing from the outdoor heat exchanger 103 to the liquid phase branch pipe 41 is a gas-liquid two-phase refrigerant, the gas-liquid two-phase refrigerant can pass through the plurality of first through holes on the mixed flow member 50 It flows from one end of the first flow pipe 411 to the other end, and flows into the two second flow pipes 412 respectively, thereby flowing to the first indoor heat exchanger 1081 and the first flow pipe 411 of the next liquid phase branch pipe 41 respectively.

For example, the structure of the branch pipe 40 may be a T-shaped structure. For example, referring to FIG. 12A , the first flow tube 411 in the liquid phase branch pipe 41 can be directly connected to a second flow tube 412 along the X to X′ direction (that is, the axial direction of the first flow tube 411 is connected to the second flow tube 412 The axial direction of the tube 412 is parallel) and can be connected with another second flow tube 412 along the Y to Y' direction (that is, the axial direction of the first flow tube 411 is perpendicular to the axial direction of the other second flow tube 412 ). Alternatively, as shown in Figure 12B, the two second flow tubes 412 can also be connected in the same direction, that is, one end of the first flow tube 411 can be vertically connected between the two second flow tubes 412; or, as shown in Figure As shown in 13, one end of the first flow tube 411 is connected to one end of the two second flow tubes 412, and there is an included angle between the first flow tube 411 and the two second flow tubes 412. In some embodiments, The included angle between the first flow tube 411 and the two second flow tubes 412 may be the same, for example, the included angle may be 15°.

By way of example, the liquid phase branch tube 41 may include three, four or more second flow tubes 412 . For example, when the number of the second flow tubes 412 is three, the axes of the three second flow tubes 412 can be coplanar or out of plane, and the angle between the axes of two adjacent second flow tubes 412 can be The angle between the axis of the first flow tube 411 and the axis of the second flow tube 412 may also be the same.

It should be noted that since the number of indoor units 20 in the air conditioning system 1 may be two or more, when connecting the indoor heat exchanger 108 and the outdoor heat exchanger 103, the number of liquid phase branch pipes 41 may be determined by the liquid phase branch pipe 41. The number of second flow pipes 412 included in the branch pipe 41 is determined accordingly. For example, when the number of the second flow pipes 412 of the liquid phase branch pipe 41 is two, the number of the liquid phase branch pipe 41 may be one less than the number of the indoor units 20; or, when the number of the second flow pipes 412 of the liquid phase branch pipe 41 is When the number of pipes 412 is three, the number of liquid phase branch pipes 41 may be two less than the number of indoor units 20 .

In some embodiments, the indoor heat exchanger 108 and the four-way valve 111 may be connected through the gas phase branch pipe 42 . The structure of the gas phase branch pipe 42 is similar to the structure of the liquid phase branch pipe 41 in the above embodiment, or other three-way or multi-way structures can be used to connect multiple indoor heat exchangers 108 and the four-way valve 111 .

Therefore, after at least one mixing component 50 is installed in the first flow tube 411, when the gas-liquid two-phase refrigerant passes through the plurality of first through holes on the mixing component 50, the larger bubbles formed by the gas-phase refrigerant will pass through the multiple first through holes. When a first through hole is formed, it will be split by the first through hole under the action of inertia and form a plurality of smaller bubbles, which is conducive to improving the mixing degree of the gas phase refrigerant into the liquid phase refrigerant, thus significantly reducing the gas-liquid two-phase refrigerant. The gas-liquid splitting phenomenon in the process of branching from the first flow pipe 411 to the plurality of second flow pipes 412 allows the amount of refrigerant flowing through the indoor heat exchanger 108 in each indoor unit 20 to be distributed relatively evenly, so that each Each indoor unit 20 can reach the rated cooling capacity, which ensures that each indoor unit 20 has a good cooling effect and improves the stability of the air conditioning system 1 operating under cooling conditions.

For example, the number of flow mixing members 50 may be two or more to improve the cutting and crushing effect of large bubbles in the gas-liquid two-phase refrigerant, thereby improving the mixing degree of the gas-liquid two-phase refrigerant. Alternatively, a flow mixing component 50 can also be installed in the first flow pipe 411, which improves the mixing degree of the gas-liquid two-phase refrigerant and has a simple structure. In some embodiments, when the first flow tube 411 includes multiple flow mixing members 50 , as shown in FIG. 12B and FIG. 13 , the multiple flow mixing members 50 may be installed at intervals.

As shown in FIG. 14 , in some embodiments, the flow mixing member 50 includes at least one first mixing piece, and the first mixing piece has a mesh structure with a plurality of second through holes 513 (for example, refer to FIG. 16 ), the plurality of second through holes 513 are used to communicate with both ends of the first flow tube 411 .

For example, as shown in FIG. 14 , the first mixed flow sheet may be a woven mesh mixed flow sheet 51 , for example. FIG. 15 is a structural diagram of the first flow tube 411 along line A-A in FIG. 14 , that is, at least one mesh mixing plate 51 is provided inside the first flow tube 411 .

Figure 16 is a partially enlarged schematic diagram of part D in Figure 15. In some embodiments, as shown in FIG. 16 , the mesh mixed flow 51 may also include a plurality of wires 511 and a first mounting ring 512 . The wire 511 can be a metal wire or a wire made of non-metal material with a certain strength; the first mounting ring 512 can be a metal ring or a ring-shaped structure made of a non-metal material with a certain strength. Its shape can be adapted to the inner wall of the first flow tube 411. Both ends of the wire 511 can be connected to the inner wall of the first mounting ring 512 respectively, and a plurality of wires 511 are interlaced and woven to form a mesh structure with a plurality of second through holes 513 . The first mounting ring 512 can be placed in the first flow tube 411 and connected to the inner wall of the first flow tube 411, so that the plurality of second through holes 513 can connect both ends of the first flow tube 411, that is, the gas and liquid ends. The phase refrigerant can flow from one end of the first flow tube 411 to the other end through the plurality of second through holes 513 . For example, the wire 511 forming the second through hole 513 may have a smaller diameter, which is more conducive to cutting the flowing bubbles and improving the uniformity of the mixing of the gas-liquid two-phase refrigerant.

In other examples, as shown in FIG. 16 , the mesh mixed flow sheet 51 may only include a plurality of wires 511 . Wherein, both ends of the wire 511 can be connected to the inner wall of the first flow tube 411 respectively, so that the wire 511 is in a tight state, and a plurality of wires 511 can be interlaced and woven to form a mesh structure with a plurality of second flow tubes 411 . The through hole 513 is used to connect the two ends of the first flow tube 411 .

For example, the hole shape of the second through hole 513 may be a square as shown in Figure 16; or, the hole shape of the second through hole 513 may be a diamond shape as shown in Figure 17; or, the second through hole 513 The hole pattern can be a triangle as shown in Figure 18.

For example, as shown in Figure 14, in the first flow tube 411, at least one woven mesh mixed flow piece 51 can be installed along the X to X' direction, and the woven mesh mixed flow piece 51 can fill the first flow pipe in the radial direction. 411 interior space. In this way, when the gas-liquid two-phase refrigerant flows through the first flow tube 411, the bubbles of the gas-phase refrigerant can be cut by the plurality of wires to form a plurality of smaller bubbles (approximately The size of the second through hole 513), thereby improving the uniformity of mixing of the gas phase refrigerant and the liquid phase refrigerant.

In some embodiments, in the woven mesh mixed flow sheet 51, while ensuring the structural strength, the size of the plurality of wires 511 can be as fine as possible, so that the porosity of the woven mesh mixed flow sheet 51 is close to 100%, so that the third When the refrigerant in a flow tube 411 flows through the second through hole 513, it has a better flow effect. In the mesh mixed flow sheet 51, the mesh number of the second through holes 513 is the number of the second through holes 513 per square inch of the mesh mixed flow sheet 51, which can be expressed as the mesh number n=(24.5/(D1+D2) ) ² , where D1 is the diameter of the second through hole 513 and D2 represents the diameter of the wire 511 . For example, the mesh number of the first through holes 413 on the mesh mixed flow sheet 51 may be 40 to 635.

For example, when a plurality of woven mesh mixed flow pieces 51 are installed in the first flow tube 411, as shown in Figure 14, in the first flow pipe 411, along the direction from X to X', the woven mesh mixed flow can be made The mesh number of the second through holes 513 on the sheet 51 gradually increases. That is, from left to right, the diameter of the second through hole 513 on the mesh mixed flow sheet 51 gradually decreases. In this way, when the air-conditioning system 1 is in the cooling condition, the bubbles of the gas-phase refrigerant flowing through the plurality of woven mesh mixed flow sheets 51 from left to right can be cut into smaller-sized bubbles, which is beneficial to improve the efficiency of the gas-liquid two-phase refrigerant. degree of mixing.

Figure 19 is a structural diagram of the first flow tube 411 in Figure 14 along line B-B. In some embodiments, as shown in Figures 14 and 19, the flow mixing member 50 also includes at least one second mixing piece. The second mixing piece It includes a first sheet-like body 521, and a plurality of third through holes 522 are provided on the first sheet-like body 521, and the third through holes 522 are used to connect two ends of the first flow tube 411.

For example, as shown in FIG. 14 , the second mixed flow piece may be, for example, the first orifice plate mixed flow piece 52 .

In some embodiments, as shown in FIG. 19 , the first orifice mixing plate 52 may also include a second mounting ring 523 , and the edge of the first sheet body 521 may be connected to the inner wall of the second mounting ring 523 . The first orifice mixing plate 52 can be installed in the first flow tube 411 through the second installation ring 523, and the outer wall of the second installation ring 523 can be in contact with the inner wall of the first flow tube 411, so as to The first orifice mixing plate 52 is connected and installed at a preset position of the first flow pipe 411 .

In some embodiments, the first sheet-like body 521 and the second mounting ring 523 may be of a split structure, or the first sheet-like body 521 and the second mounting ring 523 may be of an integrated structure. For example, the edge of the first sheet-like body 521 can be bent axially toward the same side to form a flange structure similar to the second mounting ring 523 , and the shape of the flange structure can be adjusted accordingly to adapt to the first flow tube 411 inner wall. Alternatively, the first orifice plate mixed flow plate 52 can also be installed at a preset position of the first flow pipe 411; or a slot structure can also be provided on the inner wall of the first flow pipe 411 at a preset position, and The edge of the first sheet-shaped body 521 is clamped into the slot structure along the radial direction to complete the clamping installation of the first orifice plate mixing plate 52 . For example, when the first flow tube 411 and the first sheet-shaped body 521 are both of metal structure, the inner walls of the first sheet-shaped body 521 and the first flow tube 411 can also be directly welded to install the first orifice plate mixed flow plate 52 at the preset position in the first flow tube 411.

For example, as shown in FIG. 19 , the hole shape of the third through hole 522 of the first orifice plate mixed flow plate 52 may be hexagonal; or, the hole shape of the third through hole 522 may also be as shown in FIG. 20 round hole type.

In some embodiments, when the first orifice plate mixing plate 52 is made of metal material, holes can be directly punched on the first sheet body 521 to form a plurality of third through holes 522; or, they can also be directly cast to form the plurality of third through holes 522. The first sheet body 521 has a plurality of third through holes 522 . In other examples, when the first orifice plate mixing plate 52 is made of plastic or other non-metallic materials, an injection molding process can be used to directly produce the first sheet-like body 521 with a plurality of third through holes 522 .

In some embodiments, the first orifice plate mixed flow plate 52 may be provided with 25 to 60 third through holes 522, wherein the arrangement of the plurality of third through holes 522 on the first sheet body 521 can be Arranged in a matrix, it can also be arranged in a Z-shaped, K-shaped, 45° or 60° staggered arrangement to ensure that the first orifice plate mixed flow plate 52 has a high porosity to reduce the impact of pressure loss on the refrigerant. .

Figure 21 is a structural diagram of the first flow tube 411 in Figure 14 along line C-C. In some embodiments, as shown in Figures 14 and 21, the flow mixing member 50 also has at least one third mixing piece, and the third mixing piece includes The second sheet-like body 531 is provided with a plurality of fourth through holes 532 , and the plurality of fourth through holes 532 are used to connect two ends of the first flow tube 411 .

For example, as shown in FIG. 14 , the third mixed flow plate may be a second orifice plate mixed flow plate 53 .

Figure 22 is a structural diagram of a second orifice plate mixed flow plate 53. In some embodiments, the fourth through hole 532 has a coincident cross section with a plane parallel to the second sheet body 531 . Along the direction from X to X' in FIG. 22 (i.e., the flow direction of the refrigerant), the cross-sectional area of the fourth through hole 532 may gradually decrease from left to right (i.e., forward installation). 14, when the second orifice plate mixed flow plate 53 is installed in the first flow tube 411, for example, along the direction from X to X', the cross section of the fourth through hole 532 on the second orifice plate mixed flow plate 53 is The area can be gradually reduced. In this case, when the air conditioning system 1 is in the cooling condition, the pressure of the refrigerant flowing from X to The flow speed of the refrigerant in the four through holes 532.

In other examples, the second orifice plate mixing plate 53 can also be installed in the first flow tube 411 in reverse. That is, the second orifice plate mixing plate 53 is installed in the first flow tube 411 from left to right. In this case, the cross-sectional area of the fourth through hole 532 on the second orifice plate mixing plate 53 gradually increases. Therefore, when the air conditioning system 1 is in the cooling mode, the pressure of the refrigerant flowing from left to right continues to decrease when passing through the plurality of fourth through holes 532, which is beneficial to reducing the flow of the refrigerant flowing through the fourth through holes 532. speed.

For example, the second sheet-shaped body 531 in the second orifice plate mixed flow sheet 53 has a certain thickness along X to X’ (or the axial direction of the first flow tube 411). For example, the thickness of the second sheet-like body 531 may be 0.5 mm˜5 mm. For example, the second sheet-like body 531 with a plurality of fourth through holes 532 can be produced through punching, casting or through-hole injection molding.

In some embodiments, as shown in Figure 23, the third mixed flow piece also includes a plurality of sleeve members 533. The plurality of sleeve members 533 are respectively connected to the same side of the second sheet body 531, and one sleeve member 533 is connected to a third sleeve member 533. The four-through holes 532 are aligned to connect two ends of the first flow tube 411 .

For example, as shown in Figure 23 in the direction from X to Therefore, the fourth through hole 532 can extend in the X' direction along the axial direction of the second orifice plate mixing plate 53 . Alternatively, as shown in FIG. 24 , a plurality of sleeve members 533 can also be connected to the X side of the second sheet body 531 respectively, and one sleeve member 533 is aligned with a fourth through hole 532 , so that the fourth through hole 532 It can extend to the left along the axial direction of the second orifice plate mixing plate 53 .

In this case, when the thickness of the second sheet-like body 531 is thin, the length of the fourth through hole 532 in the axial direction is also extended by a plurality of second sleeve members 533 . Correspondingly, the sleeve member 533 may be provided with through holes along the X to X′ direction as an extension structure of the fourth through hole 532 . In some embodiments, the cross-sectional area of the sleeve member 533 may be larger or smaller than the cross-sectional area of the fourth through hole 532, and the sleeve member 533 may be smoothly connected to an inner wall edge of a fourth through hole 532, so that the third through hole 532 can be connected smoothly. The cross-sectional area of the four-through hole 532 may gradually increase or decrease when extending from the second sheet-shaped body 531 to the sleeve member 533 . Therefore, the fourth through hole 532 with a longer axial length is beneficial to control the flow of the refrigerant, so as to increase or slow down the flow rate of the refrigerant. Moreover, since there is no need to use the second sheet-shaped body 531 with a larger thickness, it is also beneficial to reduce the mass of the second orifice plate mixed flow piece 53 and save manufacturing materials.

For example, the sleeve member 533 can be an integral structure with the second sheet body 531. For example, the sleeve member can be formed by directly punching holes on the second sheet body 531 and extending the flange formed after punching. 533. Since no punching waste is formed, the utilization efficiency of the raw material of the second sheet body 531 is greatly increased, and the production method is very simple.

In some embodiments, at least two of the mesh mixed flow plate 51 , the first orifice plate mixed flow plate 52 and the second orifice plate mixed flow plate 53 can be respectively installed in the first flow tube 411 . In some embodiments, the number of the first orifice mixing plates 52 in the first flow tube 411 may be one or more. Correspondingly, the number of mesh mixed flow pieces 51 in the first flow tube 411 may be one or more.

When at least one mesh mixed flow plate 51 and the first orifice plate mixed flow plate 52 are installed in the first flow pipe 411, for example, at least one first orifice plate can be installed in the first flow pipe 411 from left to right. Mixing flow piece 52 and at least one mesh mixing flow piece 51. In some embodiments, the aperture of the second through hole 513 may be larger than the aperture of the third through hole 522 , that is, the cross-sectional area of the second through hole 513 is larger than the cross-sectional area of the third through hole 522 . At this time, when at least one (for example, one) first orifice plate mixed flow piece 52 and at least one mesh mixed flow piece 51 are installed in the first flow pipe 411 from left to right, when the air conditioning system 1 is in the cooling mode When the gas-liquid two-phase refrigerant flows through the first flow tube 411 from left to right, the larger bubbles in the gas-phase refrigerant can first pass through the second through hole 513 to cut the larger bubbles into multiple and the second through-holes 513. The through holes 513 have smaller bubbles with similar diameters. Subsequently, smaller bubbles can pass through the third through hole 522 and be cut by the wire 511 at the edge of the third through hole 522 to form multiple smaller bubbles (approximately the diameter of the third through hole 522 ). In this way, large bubbles in the gas phase refrigerant can be cut multiple times to form multiple smaller bubbles, which is beneficial to further improving the mixing degree of the gas phase refrigerant and the liquid phase refrigerant.

For example, as shown in Figure 14, along the flow direction of the refrigerant (the direction of the arrow shown in the figure, such as the flow direction of the refrigerant during refrigeration conditions), that is, the X to X' direction, the first flow tube 411 can sequentially The second orifice plate mixed flow piece 53, the first orifice plate mixed flow piece 52 and the mesh mixed flow piece 51 are provided to facilitate sequential cutting of bubbles formed by the gas phase refrigerant.

For example, as shown in FIG. 25 , a second orifice plate mixed flow piece 53 , a first orifice plate mixed flow piece 52 , and two woven mesh mixed flow pieces can be arranged at intervals along the X to X' direction in the first flow tube 411 . 51 and the second orifice plate mixed flow piece 53. Among them, the second orifice plate mixed flow plate 53 located on the The flow rate of the refrigerant of the plurality of fourth through holes 532 is high, and the second sheet-like body 531 at the edge of the fourth through holes 532 can preliminarily cut larger-sized bubbles in the gas phase refrigerant. In this way, by accelerating the refrigerant flowing through the fourth through hole 532 on the , so that the bubbles in the gas-phase refrigerant can be cut twice through the plurality of third through holes 522 to improve the mixing degree of the gas-liquid two-phase refrigerant.

Continuing to refer to FIG. 25 , since the diameter of the third through hole 522 is larger, in order to further cut and separate the bubbles in the gas phase refrigerant. Two woven mesh mixed flow plates 51 with gradually increasing mesh numbers (that is, gradually decreasing aperture diameter) can be installed on the X' side of the first orifice plate mixed flow plate 52. Since the cross-sectional area of the second through holes 513 of the woven mesh mixed flow plate 51 on the The separated bubbles are further divided into a plurality of bubbles approximately the same size as the second through hole 513 . Subsequently, when the refrigerant flows through the plurality of second through holes 513 on the X' side, since the diameter of the second through holes 513 is further reduced, the bubbles in the liquid phase refrigerant can continue to be cut and separated. In this way, by cutting and separating the gas-phase refrigerant four times, the uniformity of the mixing of the gas-liquid two-phase refrigerant is greatly improved, thereby preventing the gas-phase refrigerant in the mixed refrigerant from flowing concentratedly through the liquid-phase branch pipe 41 to some of the indoor units 20 for indoor heat exchange. in the device 108 to avoid the problem of sharp decline in the cooling capacity of some indoor units 20 and ensure that each indoor unit 20 has a better cooling effect.

It should be noted that in the first flow tube 411, since the hole structure of the flow mixing member 50 through which the refrigerant flows sequentially decreases, the local pressure increases, which increases the circulation speed of the refrigerant. In order to allow the refrigerant to have a longer contact time with the indoor heat exchanger 108 when flowing through the indoor heat exchanger 108, in some embodiments, as shown in Figure 25, X' of the two mesh mixed flow sheets 51 can be A reversely arranged second orifice plate mixing plate 53 is installed on the side, that is, the cross-sectional area (i.e., aperture) of the corresponding fourth through hole 532 increases sequentially from X to X'. In this way, when the uniformly mixed refrigerant flows through the plurality of fourth through holes 532 on the X' side, since the cross-sectional areas of the fourth through holes 532 increase sequentially from X to It is beneficial to reduce the flow speed of the refrigerant, so that the refrigerant can stay in the indoor heat exchanger 108 for a longer time to fully absorb heat through the indoor heat exchanger 108, thereby improving the cooling effect of the indoor unit 20.

In other examples, a forwardly arranged second orifice plate mixed flow piece 53 can also be installed at the left end of the first flow pipe 411 , and at the same time, a reversely arranged second orifice plate mixed flow piece 53 can be installed at the right end of the first flow pipe 411 53. The corresponding first orifice plate mixed flow piece 52 and/or the mesh mixed flow piece 51 can be installed between the two second orifice plate mixed flow pieces 53; The second orifice plate mixed flow piece 53 is installed on the X' side of the second orifice plate mixed flow piece 53 at the same time. The first orifice plate mixed flow piece 52 and/or the mesh mixed flow piece 51 is installed at the same time. Alternatively, a reversely arranged second orifice plate mixed flow piece 53 can also be installed at the right end of the first flow pipe 411, and at the same time, the first orifice plate mixed flow piece 52 and/or can be installed on the X side of the second orifice plate mixed flow piece 53. Mesh mixed flow piece 51.

Embodiments of the present disclosure provide a control method for an air conditioning system. 1 and 2 , the air conditioning system may be the air conditioning system 1 in any of the above embodiments. The air conditioning system 1 includes an outdoor unit 10 , an indoor unit 20 and a controller 30 . Among them, the outdoor unit 10 includes a compressor 102, an outdoor electronic expansion valve 104 and an outdoor heat exchanger 103; the indoor unit 20 includes an indoor electronic expansion valve 107 and an indoor heat exchanger 108. The compressor 102 compresses the refrigerant and discharges the compressed refrigerant. The outdoor heat exchanger 103 condenses the compressed refrigerant. The outdoor electronic expansion valve 104 and the indoor electronic expansion valve 107 sequentially condense the refrigerant in the outdoor heat exchanger 103. The amount of refrigerant is adjusted, and the indoor heat exchanger 108 evaporates the refrigerant adjusted by the indoor electronic expansion valve 107 . Figure 26 is a flow chart of a control method for an air conditioning system provided by some embodiments of the present disclosure. As shown in Figure 26, the control method of the air conditioning system includes steps 2610 to 2630.

Step 2610: Obtain the opening of the indoor electronic expansion valve 107.

Step 2620: When the first preset condition is met, adjust the opening of the outdoor electronic expansion valve 104 according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval, and adjust the opening of the outdoor electronic expansion valve 104 according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval. According to the relationship between the exhaust gas superheat degree and the target exhaust superheat degree interval, the opening of the indoor electronic expansion valve 107 is adjusted.

The first preset condition includes that the opening of the indoor electronic expansion valve 107 is smaller than the first preset opening.

Step 2630: If the first preset condition is not met, adjust the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107 according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval. opening.

In some embodiments, the indoor unit is a plurality of indoor units, and the control method of the air conditioning system further includes: when the first preset condition is met and the second preset condition is met, the exhaust superheat degree of the compressor 102 is determined. In relation to the target exhaust superheat interval, the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107 are adjusted; when the first preset condition is met and the second preset condition is not met, according to The relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling degree interval, adjusting the opening of the outdoor electronic expansion valve 104, and the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval, Adjust the opening of the indoor electronic expansion valve 107; wherein, the second preset condition includes: the opening of the target indoor electronic expansion valve in the target indoor unit is greater than or equal to the second preset opening, the target indoor air exchanger in the target indoor unit The superheat degree of the heater is greater than or equal to the target superheat degree, and the exhaust superheat degree of the compressor 102 is greater than or equal to the upper limit value in the target exhaust superheat degree range; the target indoor unit is one of the plurality of indoor units 20 ; The second preset opening is greater than the first preset opening.

In some embodiments, the opening of the outdoor electronic expansion valve 104 is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger 103 and the first target subcooling interval, including: if the subcooling degree of the outdoor heat exchanger 103 is greater than The upper limit value of the first target subcooling degree interval increases the opening of the outdoor electronic expansion valve 104; if the subcooling degree of the outdoor heat exchanger 103 is less than the lower limit value of the first target subcooling degree interval, decreases the opening degree of the outdoor electronic expansion valve 104. The opening of the expansion valve 104; if the subcooling of the outdoor heat exchanger is greater than or equal to the lower limit of the first target subcooling interval and less than or equal to the upper limit of the first target subcooling interval, the outdoor electronics are controlled. The opening of the expansion valve 104 remains unchanged.

In some embodiments, the opening of the indoor electronic expansion valve 107 is adjusted according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat range, including: if the exhaust superheat degree of the compressor 102 is greater than the target superheat degree If the exhaust superheat of the compressor 102 is less than the lower limit of the target superheat interval, reduce the opening of the indoor electronic expansion valve 107; if the compressor The exhaust superheat of 102 is greater than or equal to the lower limit of the target superheat interval and less than or equal to the upper limit of the target superheat interval, and the opening of the electronic expansion valve 107 in the control room remains unchanged.

In some embodiments, the compressor 102 compresses the refrigerant and discharges the compressed refrigerant, the indoor heat exchanger 108 condenses the compressed refrigerant, and the indoor electronic expansion valve 107 and the outdoor electronic expansion valve 104 sequentially condense the indoor heat exchanger. 108 to adjust the amount of condensed refrigerant, and the outdoor heat exchanger 103 evaporates the refrigerant adjusted by the outdoor electronic expansion valve 104. The control method of the air conditioning system also includes: obtaining the opening of the outdoor electronic expansion valve 104; when the third preset condition is met, based on the relationship between the subcooling degree of the indoor heat exchanger 103 and the second target subcooling degree interval, Adjust the opening of the indoor electronic expansion valve 107, and adjust the outdoor electronic expansion valve 104 according to the relationship between the superheat degree of the compressor 102 and the target exhaust superheat degree interval; if the third preset condition is not met, adjust the outdoor electronic expansion valve 104 according to the relationship between the superheat degree of the compressor 102 and the target exhaust superheat degree interval. The relationship between the superheat degree and the target exhaust superheat degree interval is to adjust the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107; wherein, the third preset condition includes that the opening of the outdoor electronic expansion valve 104 is smaller than the third Preset opening.

In some embodiments, the control method of the air conditioning system further includes: when the third preset condition is met and the fourth preset condition is met, based on the exhaust superheat degree of the compressor 102 and the target exhaust superheat degree interval. relationship, adjust the opening of the outdoor electronic expansion valve 104 and the opening of the indoor electronic expansion valve 107; when the third preset condition is met and the fourth preset condition is not met, according to the subcooling of the indoor heat exchanger 103 The opening degree of the indoor electronic expansion valve 107 is adjusted according to the relationship between the superheat degree and the second target subcooling degree interval, and the outdoor electronic expansion valve 104 is adjusted according to the relationship between the superheat degree of the compressor 102 and the target exhaust superheat degree interval; wherein, the fourth The preset conditions include: the opening of the outdoor electronic expansion valve 104 is greater than or equal to the fourth preset opening, and the exhaust superheat of the compressor 102 is greater than or equal to the upper limit of the target exhaust superheat interval; the fourth preset The opening is greater than the third preset opening.

In some embodiments, the opening of the indoor electronic expansion valve 107 is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger 103 and the second target subcooling interval, including: if the subcooling degree of the indoor heat exchanger 108 is greater than The upper limit of the second target subcooling interval increases the opening of the indoor electronic expansion valve 107; if the subcooling of the indoor heat exchanger 108 is less than the lower limit of the second target subcooling interval, decreases the opening of the indoor electronic expansion valve 107. The opening of the expansion valve 107; if the subcooling degree of the indoor heat exchanger 108 is greater than or equal to the lower limit of the second target subcooling interval and less than or equal to the upper limit of the second target subcooling interval, the control room The opening of the electronic expansion valve remains unchanged.

In some embodiments, the opening of the outdoor electronic expansion valve 104 is adjusted according to the relationship between the exhaust superheat degree of the compressor 102 and the target exhaust superheat range, including: if the exhaust superheat degree of the compressor 102 is greater than the target superheat degree If the exhaust superheat of the compressor 102 is less than the lower limit of the target superheat interval, reduce the opening of the outdoor electronic expansion valve 104; if the compressor If the exhaust superheat is greater than or equal to the upper limit of the target superheat interval and less than or equal to the lower limit of the target superheat interval, the opening of the outdoor electronic expansion valve 104 is controlled to remain unchanged.

The control method of the above air conditioning system has the same beneficial effects as the air conditioning system described in some of the above embodiments, and will not be described again here.

It should be noted that the steps described in a specific order in the drawings of the embodiments of the present disclosure do not require or imply that these steps must be performed in this specific order, or that all steps shown must be performed to achieve the desired results. Each step in the drawings may be appended, some steps may be omitted, multiple steps may be combined into one step for execution, or one step may be decomposed into multiple steps for execution, etc.

Those skilled in the art will understand that the disclosure scope of the present application is not limited to the specific embodiments described above, and certain elements of the embodiments may be modified and replaced without departing from the spirit of the application. The scope of the application is limited by the appended claims.

Claims (20)

1. An air conditioning system including:

   Outdoor unit, including compressor, outdoor electronic expansion valve and outdoor heat exchanger;

   The indoor unit includes an indoor electronic expansion valve and an indoor heat exchanger; wherein, the compressor compresses the refrigerant and discharges the compressed refrigerant, and the outdoor heat exchanger condenses the compressed refrigerant, so The outdoor electronic expansion valve and the indoor electronic expansion valve respectively adjust the refrigerant amount of the refrigerant after being condensed by the outdoor heat exchanger, and the indoor heat exchanger adjusts the refrigerant amount after being adjusted by the indoor electronic expansion valve. The refrigerant evaporates;

   Controller, configured as:

   Obtain the opening of the indoor electronic expansion valve;

   When the first preset condition is met, the opening of the outdoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval, and the opening of the outdoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval. The relationship between the exhaust superheat degree and the target exhaust superheat degree interval is used to adjust the opening of the indoor electronic expansion valve;

   When the first preset condition is not met, the opening of the outdoor electronic expansion valve and the indoor value are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. The opening of the electronic expansion valve;

   Wherein, the first preset condition includes that the opening of the indoor electronic expansion valve is smaller than the first preset opening.
2. The air conditioning system according to claim 1, wherein the indoor unit is a plurality of indoor units, and the controller is further configured to:

   When the first preset condition is met and the second preset condition is met, the outdoor electronic expansion valve is adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. and the opening of the indoor electronic expansion valve;

   When the first preset condition is met and the second preset condition is not met, the adjustment is performed according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval. The opening of the outdoor electronic expansion valve, and adjusting the opening of the indoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval;

   Wherein, the second preset condition includes: the opening degree of the target indoor electronic expansion valve in the target indoor unit is greater than or equal to the second preset opening degree, and the superheat degree of the target indoor heat exchanger in the target indoor unit is greater than or equal to the second preset opening degree. or equal to the target superheat degree, and the exhaust superheat degree of the compressor is greater than or equal to the upper limit value in the target exhaust superheat degree interval; the target indoor unit is one of the plurality of indoor units. ; The second preset opening is greater than the first preset opening.
3. The air conditioning system according to claim 1 or 2, wherein the controller is configured to:

   If the subcooling degree of the outdoor heat exchanger is greater than the upper limit of the first target subcooling degree interval, increase the opening of the outdoor electronic expansion valve;

   If the subcooling degree of the outdoor heat exchanger is less than the lower limit of the first target subcooling degree interval, reduce the opening of the outdoor electronic expansion valve;

   If the subcooling degree of the outdoor heat exchanger is greater than or equal to the lower limit of the first target subcooling interval and less than or equal to the upper limit of the first target subcooling interval, the outdoor heat exchanger is controlled to The opening of the electronic expansion valve remains unchanged.
4. The air conditioning system according to claim 1, wherein the compressor compresses the refrigerant and discharges the compressed refrigerant, the indoor heat exchanger condenses the compressed refrigerant, and the indoor electronic expansion The valve and the outdoor electronic expansion valve respectively adjust the amount of refrigerant condensed by the indoor heat exchanger, and the outdoor heat exchanger evaporates the refrigerant adjusted by the outdoor electronic expansion valve;

   The controller is also configured to:

   Obtain the opening of the outdoor electronic expansion valve;

   When the third preset condition is met, the opening of the indoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger and the second target subcooling degree interval, and the opening of the indoor electronic expansion valve is adjusted according to the compressor The relationship between the exhaust superheat degree and the target exhaust superheat degree interval is used to adjust the opening of the outdoor electronic expansion valve;

   If the third preset condition is not met, the opening of the outdoor electronic expansion valve and the indoor value are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. The opening of the electronic expansion valve;

   Wherein, the third preset condition includes that the opening of the outdoor electronic expansion valve is smaller than the third preset opening.
5. The air conditioning system according to claim 4, wherein the controller is further configured to:

   When the third preset condition and the fourth preset condition are met at the same time, the outdoor electronic expansion valve is adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. The opening degree and the opening degree of the indoor electronic expansion valve;

   When the third preset condition is met and the fourth preset condition is not met, the indoor heat exchanger is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger and the second target subcooling degree interval. the opening of the electronic expansion valve, and adjusting the opening of the outdoor electronic expansion valve according to the relationship between the exhaust superheat of the compressor and the target exhaust superheat interval;

   Wherein, the fourth preset condition includes: the opening of the outdoor electronic expansion valve is greater than or equal to the fourth preset opening, and the exhaust superheat degree of the compressor is greater than or equal to the target exhaust superheat degree. The upper limit of the interval; the fourth preset opening is greater than the third preset opening.
6. The air conditioning system according to claim 4 or 5, wherein the controller is configured to:

   If the subcooling degree of the indoor heat exchanger is greater than the upper limit of the second target subcooling degree interval, increase the opening of the indoor electronic expansion valve;

   If the subcooling degree of the indoor heat exchanger is less than the lower limit of the second target subcooling degree interval, reduce the opening of the indoor electronic expansion valve;

   If the subcooling degree of the indoor heat exchanger is greater than or equal to the lower limit of the second target subcooling interval and less than or equal to the upper limit of the second target subcooling interval, control the indoor The opening of the electronic expansion valve remains unchanged.
7. The air conditioning system according to any one of claims 1-6, wherein the controller is configured to:

   If the exhaust superheat of the compressor is greater than the upper limit of the target superheat interval, increase the opening of at least one of the outdoor electronic expansion valve and the indoor electronic expansion valve;

   If the exhaust superheat of the compressor is less than the lower limit of the target superheat interval, reduce the opening of at least one of the outdoor electronic expansion valve and the indoor electronic expansion valve;

   If the exhaust superheat of the compressor is greater than or equal to the upper limit of the target superheat interval and less than or equal to the lower limit of the target superheat interval, the outdoor electronic expansion valve and the multiplexer are controlled. The opening of at least one of the indoor electronic expansion valves remains unchanged.
8. The air conditioning system according to claim 1, further comprising:

   At least one liquid phase branch pipe, each liquid phase branch pipe includes: a first flow pipe and a second flow pipe, one end of the second flow pipe is connected with one end of the first flow pipe, and the second flow pipe The other end of the pipe is connected to the indoor electronic expansion valve; the liquid phase branch pipe is configured to: divide or converge the refrigerant flowing through the liquid phase branch pipe;

   Wherein, the first flow tube includes at least one flow mixing component, each mixing component has a plurality of first through holes, and the plurality of first through holes are used to connect two ends of the first flow tube.
9. The air conditioning system according to claim 8, wherein the flow mixing member includes:

   At least one first mixed flow plate, each first mixed flow plate has a mesh structure, the mesh structure has a plurality of second through holes, the plurality of second through holes are used to connect two sides of the first flow tube. end.
10. The air conditioning system according to claim 8 or 9, wherein the flow mixing member further includes:

    At least one second mixed flow plate, each second mixed flow plate includes a first sheet-like body, the first sheet-like body is provided with a plurality of third through holes, the third through holes are used to communicate with the first Both ends of the flow tube;

    Wherein, in the case where the flow mixing element includes at least one first flow mixing piece, the at least one second flow mixing piece is located on a side of the at least one first flow mixing piece away from the indoor electronic expansion valve.
11. The air conditioning system according to any one of claims 8-10, wherein the flow mixing member further includes:

    At least one third mixed flow plate, each third mixed flow plate includes a second sheet-like body, the second sheet-like body is provided with a plurality of fourth through holes, the fourth through holes are used to communicate with the first both ends of the flow tube.
12. The air conditioning system according to claim 11, wherein the third mixed flow piece further includes a plurality of sleeve members, the plurality of sleeve members are respectively connected to the same side of the second sheet body, and one sleeve member is connected to the same side of the second sheet body. A third through hole is aligned to connect two ends of the first flow tube.
13. A control method for an air conditioning system, wherein the air conditioning system includes an outdoor unit, an indoor unit and a controller; the outdoor unit includes a compressor, an outdoor electronic expansion valve and an outdoor heat exchanger; the indoor unit includes: an indoor electronic unit Expansion valve and indoor heat exchanger; the compressor compresses the refrigerant and discharges the compressed refrigerant, the outdoor heat exchanger condenses the compressed refrigerant, the outdoor electronic expansion valve and the The indoor electronic expansion valve respectively adjusts the amount of the refrigerant condensed by the outdoor heat exchanger, and the indoor heat exchanger evaporates the refrigerant adjusted by the indoor electronic expansion valve;

    The methods include:

    Obtain the opening of the indoor electronic expansion valve;

    When the first preset condition is met, the opening of the outdoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval, and the opening of the outdoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval. The relationship between the exhaust superheat degree and the target exhaust superheat degree interval is used to adjust the opening of the indoor electronic expansion valve;

    When the first preset condition is not met, the opening of the outdoor electronic expansion valve and the indoor value are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. The opening of the electronic expansion valve;

    Wherein, the first preset condition includes that the opening of the indoor electronic expansion valve is smaller than the first preset opening.
14. The method according to claim 13, wherein the indoor unit is a plurality of indoor units, and the method further includes:

    When the first preset condition is met and the second preset condition is met, the outdoor electronic expansion valve is adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. and the opening of the indoor electronic expansion valve;

    When the first preset condition is met and the second preset condition is not met, the adjustment is performed according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling degree interval. The opening of the outdoor electronic expansion valve, and adjusting the opening of the indoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval;

    Wherein, the second preset condition includes: the opening degree of the target indoor electronic expansion valve in the target indoor unit is greater than or equal to the second preset opening degree, and the superheat degree of the target indoor heat exchanger in the target indoor unit is greater than or equal to the second preset opening degree. or equal to the target superheat degree, and the exhaust superheat degree of the compressor is greater than or equal to the upper limit value in the target exhaust superheat degree interval; the target indoor unit is one of the plurality of indoor units. ; The second preset opening is greater than the first preset opening.
15. The method according to claim 13 or 14, wherein adjusting the opening of the outdoor electronic expansion valve according to the relationship between the subcooling degree of the outdoor heat exchanger and the first target subcooling interval includes:

    If the subcooling degree of the outdoor heat exchanger is greater than the upper limit of the first target subcooling degree interval, increase the opening of the outdoor electronic expansion valve;

    If the subcooling degree of the outdoor heat exchanger is less than the lower limit of the first target subcooling degree interval, reduce the opening of the outdoor electronic expansion valve;

    If the subcooling degree of the outdoor heat exchanger is greater than or equal to the lower limit of the first target subcooling interval and less than or equal to the upper limit of the first target subcooling interval, the outdoor heat exchanger is controlled to The opening of the electronic expansion valve remains unchanged.
16. The method according to claim 13 or 14, wherein adjusting the opening of the indoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval includes:

    If the exhaust superheat of the compressor is greater than the upper limit of the target superheat interval, increase the opening of the indoor electronic expansion valve;

    If the exhaust superheat of the compressor is less than the lower limit of the target superheat interval, reduce the opening of the indoor electronic expansion valve;

    If the exhaust superheat of the compressor is greater than or equal to the upper limit of the target superheat interval and less than or equal to the lower limit of the target superheat interval, control the opening of the indoor electronic expansion valve to maintain constant.
17. The method according to claim 13, wherein the compressor compresses the refrigerant and discharges the compressed refrigerant, the indoor heat exchanger condenses the compressed refrigerant, and the indoor electronic expansion valve and the outdoor electronic expansion valve respectively regulate the amount of refrigerant condensed by the indoor heat exchanger, and the outdoor heat exchanger evaporates the refrigerant adjusted by the outdoor electronic expansion valve; Methods also include:

    Obtain the opening of the outdoor electronic expansion valve;

    When the third preset condition is met, the opening of the indoor electronic expansion valve is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger and the second target subcooling degree interval, and the opening of the indoor electronic expansion valve is adjusted according to the compressor The relationship between the exhaust superheat degree and the target exhaust superheat degree interval is used to adjust the opening of the outdoor electronic expansion valve;

    If the third preset condition is not met, the opening of the outdoor electronic expansion valve and the indoor value are adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. The opening of the electronic expansion valve;

    Wherein, the third preset condition includes that the opening of the outdoor electronic expansion valve is smaller than the third preset opening.
18. The method of claim 17, further comprising:

    When the third preset condition is met and the fourth preset condition is met, the outdoor electronic expansion valve is adjusted according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval. and the opening of the indoor electronic expansion valve;

    When the third preset condition is met and the fourth preset condition is not met, the indoor heat exchanger is adjusted according to the relationship between the subcooling degree of the indoor heat exchanger and the second target subcooling degree interval. the opening of the electronic expansion valve, and adjusting the opening of the outdoor electronic expansion valve according to the relationship between the exhaust superheat of the compressor and the target exhaust superheat interval;

    Wherein, the fourth preset condition includes: the opening of the outdoor electronic expansion valve is greater than or equal to the fourth preset opening, and the exhaust superheat degree of the compressor is greater than or equal to the target exhaust superheat degree. The upper limit of the interval; the fourth preset opening is greater than the third preset opening.
19. The method according to claim 17 or 18, wherein adjusting the opening of the indoor electronic expansion valve according to the relationship between the subcooling degree of the indoor heat exchanger and the second target subcooling interval includes:

    If the subcooling degree of the indoor heat exchanger is greater than the upper limit of the second target subcooling degree interval, increase the opening of the indoor electronic expansion valve;

    If the subcooling degree of the indoor heat exchanger is less than the lower limit of the second target subcooling degree interval, reduce the opening of the indoor electronic expansion valve;

    If the subcooling degree of the indoor heat exchanger is greater than or equal to the lower limit of the second target subcooling interval and less than or equal to the upper limit of the second target subcooling interval, control the indoor The opening of the electronic expansion valve remains unchanged.
20. The method according to claim 17 or 18, wherein adjusting the opening of the outdoor electronic expansion valve according to the relationship between the exhaust superheat degree of the compressor and the target exhaust superheat degree interval includes:

    If the exhaust superheat of the compressor is greater than the upper limit of the target superheat interval, increase the opening of the outdoor electronic expansion valve;

    If the exhaust superheat of the compressor is less than the lower limit of the target superheat interval, reduce the opening of the outdoor electronic expansion valve;

    If the exhaust superheat of the compressor is greater than or equal to the upper limit of the target superheat interval and less than or equal to the lower limit of the target superheat interval, control the opening of the outdoor electronic expansion valve to maintain constant.

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