Air conditioning system and control method thereof

Abstract

The embodiment of the application provides an air conditioning system and a control method thereof, relates to the technical field of air conditioning, and is used for reducing abnormal noise during defrosting of the air conditioning system. The air conditioning system comprises an outdoor heat exchanger and an indoor heat exchanger; an indoor expansion valve; a water-fluorine heat exchanger; a four-way valve; a first expansion valve and a first electromagnetic valve; a second expansion valve; a third expansion valve; and a controller configured to: acquire an operation mode of the air conditioning system, wherein the operation mode comprises a refrigeration mode, a heating mode and a hot water mode; determine whether the air conditioning system satisfies a defrosting condition in the hot water mode; in the hot water mode, the four-way valve is in a first working state, the first expansion valve is in a closed state, the first electromagnetic valve is in an open state, the second expansion valve is in an open state, the third expansion valve is in a throttling state, and the indoor expansion valve is in a closed state; and in the case that the defrosting condition is satisfied, the first electromagnetic valve is controlled to be closed, the first expansion valve is controlled to be opened, the third expansion valve is controlled to be slowly opened, and the indoor expansion valve is controlled to be throttled.

Description

Technical Field

[0001] This application relates to the field of air conditioning technology, and in particular to an air conditioning system and its control method. Background Technology

[0002] With the development of the economy and society, air conditioning systems are being used more and more widely in various places such as entertainment, home and work.

[0003] When an air conditioning system is in heating mode, frost inevitably forms on the outdoor heat exchanger. Over time, the frost layer thickens, gradually reducing the air conditioning capacity. Therefore, defrosting is necessary to maintain the system's heat exchange capacity. Currently, defrosting can cause abnormal noise in the air conditioning system. Summary of the Invention

[0004] This application provides an air conditioning system and its control method to reduce abnormal noise during defrosting.

[0005] To achieve the above objectives, this application adopts the following technical solution.

[0006] In a first aspect, embodiments of this application provide an air conditioning system, comprising: an outdoor heat exchanger and an indoor heat exchanger; wherein one functions as a condenser and the other as an evaporator; a water-refrigerant heat exchanger for exchanging heat between refrigerant and water; a four-way valve for controlling the refrigerant flow direction in the refrigerant circuit, wherein the outdoor heat exchanger functions as a condenser when the four-way valve is in a first operating state; and as an evaporator when the four-way valve is in a second operating state; a first expansion valve and a first solenoid valve for controlling the refrigerant flow direction in the system piping; wherein one end of the first expansion valve is connected to the four-way valve and the other end is connected to the indoor heat exchanger. An outdoor heat exchanger; one end of a first solenoid valve is connected to a gas-liquid separator, and the other end is connected in parallel with one end of a first expansion valve to the outdoor heat exchanger; a second expansion valve is used to control the flow rate of refrigerant to the outdoor heat exchanger; a controller is configured to: acquire the operating mode of the air conditioning system, including cooling mode, heating mode, and hot water mode; when the operating mode is hot water mode, determine whether the air conditioning system meets the defrosting conditions; wherein, in hot water mode, the four-way valve is in a first working state, the first expansion valve is in a closed state, and the first solenoid valve is in an open state; when the defrosting conditions are met, control the first solenoid valve to close and the first expansion valve to open.

[0007] The technical solution provided in this application provides at least the following beneficial effects: This application provides an air conditioning system that, in hot water mode and when defrosting conditions are met, controls the first solenoid valve to close and the first expansion valve to open. It is understood that since the four-way valve is already in its first working state in hot water mode, it does not need to readjust its working state when defrosting conditions are met. This prevents abnormal noise caused by the four-way valve switching during defrosting.

[0008] In some embodiments, in the cooling mode, the four-way valve is in a first working state, the first expansion valve is in an open state, and the first solenoid valve is in a closed state.

[0009] In some embodiments, the air conditioning system further includes a water pump connected to a water-refrigerant heat exchanger to form a water system for providing power for the circulation of water within the water system; a temperature sensor disposed on the outdoor heat exchanger for detecting the ambient temperature; a high-pressure sensor disposed on the compressor's exhaust pipe for detecting the high-pressure of the air conditioning system; and a controller configured to: acquire the ambient temperature via the temperature sensor and acquire the high-pressure of the air conditioning system via the high-pressure sensor; control the second expansion valve and the water pump to open when the ambient temperature is greater than or equal to a preset temperature and the high-pressure is greater than or equal to a preset threshold; or control the second expansion valve and the water pump to close when the ambient temperature is greater than or equal to the preset temperature and the high-pressure is less than the preset threshold.

[0010] In some embodiments, the controller is further configured to shut down the second expansion valve and the water pump when the ambient temperature is lower than a preset temperature.

[0011] In some embodiments, the air conditioning system further includes: a third expansion valve for controlling the flow rate of refrigerant to the indoor heat exchanger; an outdoor fan for dissipating heat from the outdoor heat exchanger; and a controller further configured to: acquire the indoor unit load when the air conditioning system is simultaneously operating in cooling mode and hot water mode; and when the indoor unit load is greater than a preset load, control the first expansion valve to open, the first solenoid valve to close, and adjust the opening degree of the second expansion valve to a first preset opening degree, the opening degree of the third expansion valve to a second preset opening degree, and the rotation speed of the outdoor fan to a preset rotation speed.

[0012] In some embodiments, the controller is further configured to: control the first expansion valve to close, control the first solenoid valve to open, and adjust the opening of the second expansion valve to a third preset opening and the opening of the third expansion valve to a fourth preset opening when the indoor unit load is less than a preset load.

[0013] In some embodiments, the controller is further configured to: when the indoor unit load is equal to a preset load, control the first expansion valve to close, the first solenoid valve to open, the third expansion valve to close, and adjust the opening of the second expansion valve to a fifth preset opening.

[0014] Secondly, embodiments of this application provide a control method for an air conditioning system. The method is applied to an air conditioning system and includes: acquiring the operating mode of the air conditioning system, including a cooling mode, a heating mode, and a hot water mode; when the operating mode is hot water mode, determining whether the air conditioning system meets the defrosting conditions; wherein, in the hot water mode, the four-way valve is in a first working state, the first expansion valve is in a closed state, and the first solenoid valve is in an open state; when the defrosting conditions are met, controlling the first solenoid valve to close, the first expansion valve to open, and the second expansion valve to open.

[0015] Thirdly, embodiments of this application provide a controller, including: one or more processors; one or more memories; wherein the one or more memories are used to store computer program code, the computer program code including computer instructions, and when the one or more processors execute the computer instructions, the controller executes any of the air conditioning system control methods provided in the second aspect.

[0016] Fourthly, embodiments of this application provide a computer-readable storage medium including computer instructions that, when executed on a computer, cause the computer to perform any of the air conditioning system control methods provided in the second aspect.

[0017] Fifthly, embodiments of the present invention provide a computer program product that can be directly loaded into a memory and contains software code. After being loaded and executed by a computer, the computer program product can realize any of the air conditioning system control methods provided in the second aspect.

[0018] It should be noted that the aforementioned computer instructions may be stored, in whole or in part, on a computer-readable storage medium. This computer-readable storage medium may be packaged together with the controller's processor, or it may be packaged separately from the controller's processor; this application does not impose any limitations on this.

[0019] The beneficial effects described in aspects two through five of this application can be referred to the analysis of the beneficial effects of aspect one, and will not be repeated here. Attached Figure Description

[0020] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0021] Figure 1 This is a schematic diagram of the composition of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0022] Figure 2 This is a schematic diagram of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0023] Figure 3 This is a hardware configuration block diagram of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0024] Figure 4 This is a schematic diagram of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0025] Figure 5 This is a schematic diagram of the circulation principle of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0026] Figure 6 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0027] Figure 7 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0028] Figure 8 This is a flowchart of a control method for an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0029] Figure 9 This is a schematic diagram of the component states of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0030] Figure 10 This is a schematic diagram of the component states of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0031] Figure 11 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0032] Figure 12 This is a schematic diagram of the component states of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0033] Figure 13 This is a schematic diagram of the component states of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0034] Figure 14 This is a schematic diagram of the component states of an air conditioning system provided in accordance with an exemplary embodiment of this application;

[0035] Figure 15This is a flowchart of another air conditioning system control method provided in this application according to an exemplary embodiment;

[0036] Figure 16 This is a flowchart of another air conditioning system control method provided in this application according to an exemplary embodiment;

[0037] Figure 17 This is a flowchart of another air conditioning system control method provided in this application according to an exemplary embodiment;

[0038] Figure 18 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0039] Figure 19 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application;

[0040] Figure 20 This is a schematic diagram of the circulation principle of another air conditioning system provided in accordance with an exemplary embodiment of this application. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0042] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0043] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0044] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this application have the meaning of establishing electrical connection. The specific meaning needs to be understood in conjunction with the context.

[0045] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0046] In related technologies, air conditioning systems often employ reverse defrosting, where the compressor stops before defrosting occurs. However, during the reverse switching process, the movement of the four-way valve or the adjustment of the expansion valve opening causes refrigerant switching and flow, which can lead to abnormal noise in the air conditioning system.

[0047] Based on this, this application provides a control method for an air conditioning system. When the operating mode is hot water production mode and defrosting conditions are met, the method controls the first solenoid valve to close and the first expansion valve to open. It is understood that since the four-way valve is already in its first working state in hot water production mode, it does not need to readjust its working state when defrosting conditions are met. This prevents abnormal noise caused by the four-way valve switching during defrosting.

[0048] Figure 1 This is a schematic diagram illustrating the composition of an air conditioning system provided in accordance with an exemplary embodiment of this application. Figure 1 As shown, the air conditioning system 100 includes an outdoor unit 10, multiple indoor units 20, and a water system terminal device 30.

[0049] Outdoor unit 10 is usually installed outdoors and is used for heat exchange in the indoor environment.

[0050] Indoor unit 20 is usually installed indoors, and there are pipes connecting each indoor unit 20 to outdoor unit 10.

[0051] The water system terminal equipment 30 can be equipment such as water tanks and underfloor heating coils.

[0052] Figure 2 This is a schematic diagram of the structure of an air conditioning system provided in accordance with an exemplary embodiment of this application. Figure 2As shown, the air conditioning system 100 includes a compressor 111, an outdoor heat exchanger 112, a gas-liquid separator 113, a four-way valve 114, an indoor heat exchanger 115, a water-refrigerant heat exchanger 116, a first expansion valve 117, a first solenoid valve 118, a second expansion valve 120, a third expansion valve 119, a liquid-side shut-off valve 121, a gas-side shut-off valve 122, multiple filters 123, and an indoor expansion valve 124. Figure 2 (not shown in the image), water pump 125 ( Figure 2 (not shown in the image) and controller 126 ( Figure 2 (Not shown in the image).

[0053] In some embodiments, compressor 111 is configured between four-way valve 114 and gas-liquid separator 113 to compress refrigerant delivered by gas-liquid separator 113 and deliver the compressed refrigerant to the circulation system via four-way valve 114, providing power for refrigerant circulation. Compressor 111 may be a variable-capacity inverter compressor that performs inverter-based speed control.

[0054] In some embodiments, one end of the outdoor heat exchanger 112 is connected to the compressor 111 via a four-way valve 114, and the other end is connected to the indoor heat exchanger 115. The outdoor heat exchanger 112 has a first inlet / outlet for allowing refrigerant to flow between the outdoor heat exchanger 112 and the suction port of the compressor 111 via a gas-liquid separator 113, and a second inlet / outlet for allowing refrigerant to flow between the outdoor heat exchanger 112 and the indoor heat exchanger 115. The outdoor heat exchanger 112 facilitates heat exchange between the refrigerant flowing in the heat transfer tube connected between the first and second inlets / outlets and outdoor air. In the cold cycle, the outdoor heat exchanger 112 functions as a condenser.

[0055] In some embodiments, one end of the gas-liquid separator 113 is connected to the compressor 111, and the other end is connected to the outdoor heat exchanger 112 via a four-way valve 114. In the gas-liquid separator 113, the refrigerant flowing from the outdoor heat exchanger 112 to the compressor 111 via the four-way valve 114 is separated into gaseous refrigerant and liquid refrigerant. Furthermore, gaseous refrigerant is primarily supplied from the gas-liquid separator 113 to the suction port of the compressor 111.

[0056] In some embodiments, the four-way valve 114 has a first port A, a second port B, a third port C, and a fourth port D. The first port A is connected to the compressor 111, the second port B is connected to the outdoor heat exchanger 112, the third port C is connected to the gas-liquid separator 113, and the fourth port D is connected to the indoor heat exchanger. The four-way valve 114 is used to achieve mutual conversion between cooling and heating by changing the flow direction of the refrigerant in the system piping.

[0057] In some embodiments, the four-way valve 114 has a first operating state and a second operating state. When the four-way valve is in the first operating state, the third port C is connected to the fourth port D, and the first port A is connected to the second port B, thus the outdoor heat exchanger 112 operates as a condenser. When the four-way valve is in the second operating state, the first port A is connected to the fourth port D, and the second port B is connected to the third port C, thus the outdoor heat exchanger 112 operates as an evaporator.

[0058] In some embodiments, the indoor heat exchanger 115 has a third inlet for allowing liquid refrigerant to flow between it and the outdoor heat exchanger 112, and a fourth inlet for allowing gaseous refrigerant to flow between it and the outlet of the compressor 111. The indoor heat exchanger 115 facilitates heat exchange between the refrigerant flowing in the heat transfer tube connected between the third and fourth inlets and the indoor air.

[0059] In some embodiments, the refrigerant side of the water-fluorine heat exchanger 116 is connected to the compressor 111 and the liquid side shut-off valve 121, while the other side of the water-fluorine heat exchanger 116 is provided with an inlet and an outlet, which are connected to the water pump 125 to form a flow loop in the water system. The water-fluorine heat exchanger 116 is used to exchange heat between the refrigerant and the water in the water system to achieve the purpose of heating using the water system.

[0060] In some embodiments, one end of the first expansion valve 117 is connected to the four-way valve 114 and the other end is connected to the outdoor heat exchanger 112, for changing the flow direction of refrigerant in the system pipeline.

[0061] In some embodiments, one end of the first solenoid valve 118 is connected to the gas-liquid separator 113, and the other end is connected in parallel with one end of the first expansion valve 117 to the outdoor heat exchanger 112, for changing the flow direction of refrigerant in the system pipeline.

[0062] It should be noted that the first solenoid valve 118 can also be replaced by an expansion valve.

[0063] In some embodiments, the second expansion valve 120 and the third expansion valve 119 are used to regulate the fluid flow rate in the pipeline and to regulate the refrigerant flow rate. Specifically, the second expansion valve 120 controls the flow rate of refrigerant to the indoor heat exchanger, and the third expansion valve 119 controls the flow rate of refrigerant to the outdoor heat exchanger.

[0064] In some embodiments, the liquid-side shut-off valve 121 and the gas-side shut-off valve 122 are used to control the opening and closing of the valve core to control the passage and shut-off of refrigerant.

[0065] In some embodiments, the filter 123 is used to filter impurities in the refrigerant passing through the third expansion valve 119 or the second expansion valve 120, so that the third expansion valve 119 or the second expansion valve 120 is not easily damaged.

[0066] In some embodiments, an indoor expansion valve 124 is disposed on the connecting pipe between the outdoor heat exchanger 112 and the indoor heat exchanger 115.

[0067] In some embodiments, the water pump 125 is connected to the water-fluorine heat exchanger 116 to form a water system, which provides power for water circulation within the water system. The water pump can be installed inside the indoor unit 20 as a built-in water pump, or it can be installed outside the outdoor unit 10 as an external water pump. This application embodiment does not limit the installation location of the water pump.

[0068] In the embodiments shown in this application, controller 126 refers to a device that can generate operation control signals according to instruction opcodes and timing signals, instructing the air conditioning system to execute control commands. Exemplarily, the controller can be a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The controller can also be other devices with processing functions, such as circuits, devices, or software modules; this application does not impose any limitations on this.

[0069] It should be noted that the second expansion valve 120, the third expansion valve 119, and the indoor expansion valve 124 each have three operating states:

[0070] (1) Throttling state: In the throttling state, it plays a role in throttling and reducing the pressure of the refrigerant flowing in the air conditioning circulation system pipeline. When the high-pressure refrigerant flows through any one of the second expansion valve 120, the third expansion valve 119 and the indoor expansion valve 124 in the throttling state, it becomes a low-pressure refrigerant.

[0071] (2) The open state can be fully open or open to a preset degree, and there is no limitation on this.

[0072] (3) In the closed state, the refrigerant flowing in the pipeline cannot pass through any of the second expansion valve 120, the third expansion valve 119 and the indoor expansion valve 124.

[0073] In addition, the controller 126 can be used to control the operation of various components inside the air conditioning system 100 so that the operation of each component of the air conditioning system 100 can realize the predetermined functions of the air conditioning system.

[0074] In some embodiments, the controller 126 may be integrated into the outdoor unit 10, meaning that the outdoor unit 10 can control the operation of various components in the air conditioning system 100.

[0075] Figure 3 This application provides a hardware configuration block diagram of an air conditioning system according to an exemplary embodiment. For example... Figure 3 As shown, the air conditioning system 100 may further include: a high-pressure sensor 201, a first temperature sensor 202, a second temperature sensor 203, a third temperature sensor 204, an outdoor fan 205, an outdoor fan motor 206, a display 207, an indoor fan 208, and an indoor fan motor 209.

[0076] In some embodiments, such as Figure 4 As shown, the high-pressure sensor 201 is installed on the compressor 111 and is used to detect the high-pressure of the air conditioning system 100.

[0077] In some embodiments, such as Figure 4 As shown, the first temperature sensor 202 is installed on the outdoor heat exchanger 112 to detect the ambient temperature.

[0078] In some embodiments, such as Figure 4 As shown, the second temperature sensor 203 is installed at the outlet of the water-fluoride heat exchanger 116 to detect the outlet water temperature of the water-fluoride heat exchanger 116.

[0079] In some embodiments, such as Figure 4 As shown, the third temperature sensor 204 is installed at the inlet of the water-fluoride heat exchanger 116 to detect the inlet water temperature of the water-fluoride heat exchanger 116.

[0080] In some embodiments, the outdoor fan 205 generates an airflow of outdoor air through the outdoor heat exchanger 112 to facilitate heat exchange between the refrigerant flowing in the heat transfer tube between the first inlet and the second inlet and the outdoor air.

[0081] In some embodiments, the outdoor fan motor 206 is used to drive or change the speed of the outdoor fan 205.

[0082] In some embodiments, the display 207 is used to display the indoor temperature or the current operating mode.

[0083] In some embodiments, the indoor fan 208 generates an airflow through the indoor heat exchanger 115 to facilitate heat exchange between the refrigerant flowing in the heat transfer tube between the third inlet and the fourth inlet and the indoor air.

[0084] In some embodiments, the indoor fan motor 209 is used to drive or change the speed of the indoor fan 208.

[0085] In some embodiments, the air conditioning system 100 is also equipped with a remote control, which has the function of communicating with the controller 126, for example, using infrared or other communication methods. The remote control is used by the user to perform various controls on the air conditioning system, realizing interaction between the user and the air conditioning system 100.

[0086] Those skilled in the art will understand that Figure 3 The hardware structure shown does not constitute a limitation on the multi-split air conditioning system. The multi-split air conditioning system may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0087] Figure 5 This application provides a schematic diagram of the circulation principle of an air conditioning system according to an exemplary embodiment. For example... Figure 5 As shown, when the air conditioning system is cooling alone, the four-way valve 114 is in the first working state. The high-temperature and high-pressure gaseous refrigerant discharged from the compressor 111 passes through the first port A of the four-way valve, exits through the second port B, and enters the outdoor heat exchanger 112. After exchanging heat with the air in the indoor heat exchanger, it becomes a medium-temperature and high-pressure liquid refrigerant. The refrigerant flowing out of the indoor heat exchanger is throttled and depressurized by the throttling device, becoming a low-temperature and low-pressure liquid refrigerant. After the throttling and depressurization refrigerant exchanges heat with the air in the indoor heat exchanger, it becomes a low-temperature and low-pressure gaseous refrigerant. The refrigerant flowing out of the indoor heat exchanger passes through the fourth port D of the four-way valve 114, exits through the third port C, enters the gas-liquid separator 113, and returns to the compressor 111.

[0088] Figure 6 This application provides a schematic diagram of the circulation principle of an air conditioning system according to an exemplary embodiment. For example... Figure 6 As shown, when the air conditioning system is used for heating only, the four-way valve is in the second working state. The high-temperature and high-pressure gaseous refrigerant discharged from the compressor 111 passes through the first port A of the four-way valve 114, exits through the fourth port D, and enters the indoor heat exchanger. In the indoor heat exchanger, it exchanges heat with the indoor air. After passing through the throttling device and reducing the pressure, it becomes a low-temperature and low-pressure liquid refrigerant. The refrigerant after throttling and reducing the pressure exchanges heat with the outdoor air through the outdoor heat exchanger 112, and becomes a low-temperature and low-pressure gaseous refrigerant. The refrigerant flowing out of the outdoor heat exchanger 112 passes through the second port B of the four-way valve 114, enters the gas-liquid separator 113 through the third port C, and returns to the compressor 111.

[0089] Figure 7 This application provides a schematic diagram of the circulation principle of an air conditioning system according to an exemplary embodiment. For example... Figure 7As shown, when the air conditioning system is used to produce hot water, the four-way valve is in its first working state. The high-temperature and high-pressure gaseous refrigerant discharged from the compressor 111 enters the water-fluorine heat exchanger 116, where it exchanges heat with the water in the water system. After passing through the throttling device and being depressurized, it becomes a low-temperature and low-pressure liquid refrigerant. The refrigerant after being depressurized passes through the outdoor heat exchanger 112 and exchanges heat with the outdoor air, becoming a low-temperature and low-pressure gaseous refrigerant. The refrigerant flowing out of the outdoor heat exchanger 112 enters the gas-liquid separator 113 through the first solenoid valve 118 and returns to the compressor 111.

[0090] The embodiments provided in this application will now be described in detail with reference to the accompanying drawings.

[0091] like Figure 8 As shown in the figure, this application provides a control method for an air conditioning system, the method comprising:

[0092] S101, The controller obtains the operating mode of the air conditioning system.

[0093] The operating modes include cooling mode, heating mode, and hot water mode.

[0094] In some embodiments, such as Figure 9 As shown, in the cooling mode, the four-way valve is in the first working state, the first expansion valve is in the open state, the first solenoid valve is in the closed state, the second expansion valve is in the open state and maintains a small opening, the third expansion valve is in the open state, and the indoor expansion valve is in the throttling state.

[0095] In some embodiments, such as Figure 10 As shown, in the heating mode, the four-way valve is in the second working state, the first expansion valve is in the open state, the first solenoid valve is in the closed state, the second expansion valve is in the open state and maintains a small opening to prevent refrigerant from residing in the outdoor heat exchanger, the indoor expansion valve is in the throttling state, and the third expansion valve is in the throttling state.

[0096] In some embodiments, when the operating mode is hot water production mode, the four-way valve is in the first working state.

[0097] It should be noted that cooling mode is the mode in which the air conditioning system only cools, heating mode is the mode in which the air conditioning system only heats, and hot water mode is the mode in which the air conditioning system only produces hot water. In some embodiments, the operating modes of the air conditioning system also include heating + hot water mode, etc.

[0098] In some embodiments, such as Figure 11As shown, in the heating + hot water operation mode, the four-way valve is in the second working state, the first expansion valve is in the open state, the first solenoid valve is in the closed state, the water pump is in the open state, and the indoor expansion valve and the second expansion valve are in the throttling state to simultaneously adjust the refrigerant charge of the indoor heat exchanger and the water-fluorine heat exchanger.

[0099] In some embodiments, a user can send a start-up command to the air conditioning system via a remote control or terminal device. In response to the start-up command, the controller controls the various components of the air conditioning system to start and operate, thus putting the air conditioning system into the startup state. When the air conditioning system is in the startup state, the controller acquires the operating mode of the air conditioning system and controls the various components of the air conditioning system to perform corresponding operations based on different operating modes.

[0100] In some embodiments, the user can also issue a mode switching command to the air conditioning system when the system is in cooling mode, so that the system switches to the corresponding operating mode, such as a command to switch from cooling mode to heating mode. In response to the mode switching command, the air conditioning system switches to heating mode. After the air conditioning system switches to heating mode, the controller retrieves the operating mode of the air conditioning system again.

[0101] S102. When the controller is in hot water production mode, it determines whether the air conditioning system meets the defrosting conditions.

[0102] In the hot water mode, such as Figure 12 As shown, the four-way valve is in the first working state, the first expansion valve is in the closed state, and the first solenoid valve is in the open state.

[0103] In some embodiments, in hot water production mode, the second expansion valve is in the open state, the third expansion valve is in the throttling state, and the indoor expansion valve is in the closed state.

[0104] Understandable, based on Figure 7 In the air conditioning system shown, during hot water production mode, the four-way valve is in its first operating state. High-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the water-refrigerant heat exchanger, exchanging heat with the water in the water system. The refrigerant then passes through the second and third expansion valves into the outdoor heat exchanger. After being throttled and depressurized by the third expansion valve, the refrigerant exchanges heat with the outdoor air in the outdoor heat exchanger, becoming a low-temperature, low-pressure gaseous refrigerant. Since the first expansion valve is closed, the refrigerant flowing out of the outdoor heat exchanger enters the gas-liquid separator through the first solenoid valve and returns to the compressor.

[0105] In some embodiments, defrosting conditions include compressor running time conditions and indoor coil temperature conditions, wherein the compressor running time condition is that the cumulative running time of the compressor is greater than or equal to a preset running time, and the indoor coil temperature condition is that the indoor coil temperature is less than a preset coil temperature.

[0106] Optionally, the defrosting conditions can be preset by the management personnel at the factory or obtained by the controller from other air conditioning systems; there is no limitation on this.

[0107] S103. When the defrosting conditions are met, the controller controls the first solenoid valve to close and the first expansion valve to open.

[0108] In some embodiments, such as Figure 13 As shown, when the defrosting conditions are met, the first solenoid valve is closed and the first expansion valve is opened, so that the air conditioning system automatically enters the defrosting mode.

[0109] In some embodiments, the first expansion valve is opened slowly to prevent noise caused by sudden pressure changes in the air conditioning system.

[0110] Understandable, based on Figure 7 The air conditioning system shown utilizes high-temperature refrigerant for defrosting, as the outdoor heat exchanger is frosted. Since the four-way valve is already in its first operating state in hot water mode, under the condition that defrosting is met, only the first solenoid valve needs to be closed and the first expansion valve opened to control the refrigerant flow in the system piping. No adjustment to the four-way valve's operating state is required to initiate defrosting. Furthermore, this prevents abnormal noise caused by the four-way valve switching during defrosting.

[0111] In addition, when defrosting conditions are met, the indoor unit fan will not rotate to avoid cooling the room.

[0112] For example, such as Figure 14 As shown, under the condition that the defrosting conditions are met, the high-temperature and high-pressure gaseous refrigerant discharged from the compressor passes through the first port A of the four-way valve, exits through the second port B, and enters the outdoor heat exchanger. In the outdoor heat exchanger, it releases heat and liquefies into a low-temperature and high-pressure liquid refrigerant, thereby defrosting the outdoor heat exchanger. Afterward, the refrigerant flows out of the outdoor heat exchanger and flows through the third expansion valve to the indoor heat exchanger. After exchanging heat with the air in the indoor heat exchanger, it becomes a low-temperature and low-pressure gaseous refrigerant. The refrigerant flowing out of the indoor heat exchanger passes through the fourth port D of the four-way valve, exits through the third port C, enters the gas-liquid separator, and returns to the compressor 111.

[0113] In some embodiments, when defrosting conditions are met, the third expansion valve is also controlled to open slowly to prevent refrigerant from remaining in the outdoor heat exchanger.

[0114] In some embodiments, the indoor expansion valve is also throttled when defrosting conditions are met.

[0115] based on Figure 8 The embodiment shown in this application provides a control method for an air conditioning system. When the operating mode is hot water production mode and defrosting conditions are met, the method controls the first solenoid valve to close and the first expansion valve to open. It is understood that since the four-way valve is already in its first operating state in hot water production mode, it does not need to readjust its operating state when defrosting conditions are met. This prevents abnormal noise caused by the four-way valve switching during defrosting.

[0116] In some embodiments, such as Figure 15 As shown, after controlling the first solenoid valve to close and the first expansion valve to open when the defrosting conditions are met, the control method further includes the following steps:

[0117] S201, The controller acquires the ambient temperature and the high pressure of the air conditioning system.

[0118] In some embodiments, the ambient temperature is obtained by a temperature sensor, and the high pressure of the air conditioning system is obtained by a high pressure sensor.

[0119] Optionally, when the air conditioning system is in defrost mode, the controller can periodically acquire the ambient temperature and the high pressure of the air conditioning system according to a preset cycle.

[0120] S202. When the ambient temperature is greater than or equal to the preset temperature and the high pressure is greater than or equal to the preset pressure, the controller controls the second expansion valve to throttle and the water pump to remain open.

[0121] Optionally, the preset temperature can be set by the air conditioning system at the factory or obtained by the controller from another air conditioning system; there is no limitation on this. For example, the preset temperature is 3°C. The preset pressure can also be set by the air conditioning system at the factory or obtained by the controller from another air conditioning system; there is no limitation on this. For example, the preset pressure is 1.5 MPa.

[0122] It should be noted that when the ambient temperature is greater than or equal to the preset temperature and the high-pressure is greater than or equal to the preset pressure, and the high-pressure of the air conditioning system is deemed appropriate, the defrosting speed can be guaranteed to meet expectations. Therefore, it is only necessary to control the second expansion valve to throttle the refrigerant flowing in the circulation pipeline, thereby rationally distributing the refrigerant flow. Additionally, the water pump can be kept running to continue producing hot water.

[0123] S203. When the ambient temperature is greater than or equal to the preset temperature and the high pressure is less than the preset threshold, the controller controls the second expansion valve and the water pump to shut down.

[0124] It should be noted that when the ambient temperature is greater than or equal to the preset temperature and the high-pressure pressure is less than the preset threshold, the low high-pressure pressure of the air conditioning system indicates severe frosting on the outdoor heat exchanger, resulting in a slower defrosting speed. Therefore, to improve the defrosting speed, the second expansion valve is closed, increasing the residence time of the high-temperature, high-pressure refrigerant from the compressor in the outdoor heat exchanger. This allows the refrigerant more time to melt the frost on the water-refrigerant heat exchanger, thus improving the defrosting speed. Additionally, the water pump can be shut off to stop hot water production. This prevents the low-temperature, low-pressure refrigerant from entering the water-refrigerant heat exchanger, ensuring only high-temperature, high-pressure refrigerant remains in the outdoor heat exchanger, further improving the defrosting speed.

[0125] In one possible implementation, when the ambient temperature is greater than or equal to a preset temperature and the high pressure is less than a preset threshold, the second expansion valve is periodically controlled to close according to a preset cycle.

[0126] In another possible implementation, when the ambient temperature is greater than or equal to the preset temperature and the high pressure is less than the preset threshold, the second expansion valve is controlled to close to the preset opening degree, that is, the opening degree of the second expansion valve is adjusted to the preset opening degree.

[0127] Understandably, the aforementioned preset opening is relatively small, the purpose of which is to increase the residence time of the high-temperature, high-pressure refrigerant flowing out of the compressor in the water-fluorine heat exchanger, thereby improving the defrosting speed.

[0128] S204. When the ambient temperature is lower than the preset temperature, the controller controls the second expansion valve and the water pump to shut down.

[0129] It should be noted that when the ambient temperature is lower than the preset temperature, it can be determined that the outdoor heat exchanger is severely frosted. In this case, the defrosting speed will not meet expectations. Therefore, in order to improve the defrosting speed, the second expansion valve and the water pump are also controlled to shut down. Here, please refer to the detailed description of controlling the shutdown of the second expansion valve and the water pump in step S203.

[0130] The following is combined with, for example Figure 16 The flowchart shown illustrates the complete process of the control method for the above-mentioned air conditioning system:

[0131] like Figure 16 As shown, the control process begins:

[0132] S1, the air conditioning system is operating in hot water mode.

[0133] Determine if the air conditioning system meets the defrosting requirements.

[0134] If so, proceed with steps S2 and S3 below.

[0135] If not, proceed to steps S7 and S8 below.

[0136] S2, control the first solenoid valve to close and the first expansion valve to open.

[0137] S3 controls the opening status of the third expansion valve and the throttling of the indoor expansion valve.

[0138] Determine whether the ambient temperature is greater than or equal to the preset temperature.

[0139] If so, proceed to step S4 below.

[0140] If not, proceed to step S6 below.

[0141] S4. Determine whether the high pressure is greater than or equal to the preset pressure.

[0142] If so, proceed to step S5 below.

[0143] If not, proceed to step S6 below.

[0144] S5. Control the second expansion valve to throttle and keep the water pump open.

[0145] S6. Control the second expansion valve to close and the water pump to close.

[0146] S7. Control the first expansion valve to close and the first solenoid valve to open.

[0147] S8 controls the second expansion valve to open, the third expansion valve to throttle, and the indoor expansion valve to close.

[0148] In some embodiments, such as Figure 17 As shown, the control method further includes the following steps:

[0149] S301: When the controller is in cooling mode or hot water mode, it obtains the indoor unit load.

[0150] The indoor unit load is a load generated by the discrepancy between the user-set temperature and the current indoor ambient temperature. For example, in cooling mode, if the user sets the temperature to 20°C and the actual indoor temperature is 26°C, this will generate a load, which is the indoor unit load.

[0151] Optional parameters that affect the indoor unit load include indoor ambient temperature, outdoor ambient temperature, number of indoor units, building area, indoor humidity, and set temperature.

[0152] S302. When the indoor unit load exceeds the preset load, the controller controls the first expansion valve to open, the first solenoid valve to close, and adjusts the opening degree of the second expansion valve to the first preset opening degree, the opening degree of the third expansion valve to the second preset opening degree, and the speed of the outdoor fan to the preset speed.

[0153] Optionally, the first preset opening degree, the second preset opening degree, and the preset speed can all be preset by the air conditioning system at the factory, or they can be obtained by the controller from other air conditioning systems, and there is no limitation on this.

[0154] Understandably, when the indoor unit load exceeds the preset load, the amount of refrigerant participating in the circulation is larger, and correspondingly, the amount of refrigerant participating in the circulation in the outdoor heat exchanger is also larger. To maximize the amount of refrigerant used for heat recovery and hot water production in the water-refrigerant heat exchanger, after controlling the first expansion valve to open and the first solenoid valve to close, such as... Figure 18 As shown, the outdoor heat exchanger and the water-fluorine heat exchanger are connected in parallel as a condenser, and the indoor heat exchanger is used as an evaporator. This allows the refrigerant discharged from the compressor to be split into two streams, which enter the water-fluorine heat exchanger and the outdoor heat exchanger respectively. Furthermore, by adjusting the opening of the second expansion valve and the third expansion valve, as well as the speed of the outdoor fan, the refrigerant flow rate entering the outdoor heat exchanger and the water-fluorine heat exchanger is distributed to maximize the refrigerant flow rate in the water-fluorine heat exchanger used for heat recovery to produce hot water, thereby maximizing the production of hot water.

[0155] S303. When the indoor unit load is less than the preset load, the controller controls the first expansion valve to close, controls the first solenoid valve to open, and adjusts the opening of the second expansion valve to the third preset opening and the opening of the third expansion valve to the fourth preset opening.

[0156] Optionally, the third and fourth preset opening degrees can be preset by the air conditioning system at the factory or obtained by the controller from other air conditioning systems, and there is no limitation on this.

[0157] Optionally, the user turns on an indoor unit with a smaller internal capacity. When the ambient temperature is lower than the preset threshold, the load on the indoor unit is lower than the preset load.

[0158] Understandably, when the indoor unit load is less than the preset load, the amount of refrigerant participating in the circulation in the indoor heat exchanger is relatively small. If the outdoor heat exchanger and the water-fluorine heat exchanger are connected in parallel, the refrigerant is split into two paths, entering the outdoor heat exchanger and the water-fluorine heat exchanger respectively. Furthermore, the outdoor heat exchanger is almost entirely composed of liquid refrigerant, resulting in a small flow rate of liquid refrigerant. Consequently, the amount of refrigerant participating in the circulation in the water-fluorine heat exchanger is insufficient. Therefore, the amount of refrigerant used for heat recovery to produce hot water in the water-fluorine heat exchanger is relatively small, and the pressure is low, resulting in poor performance in producing hot water through heat recovery, or even failure to produce hot water at all.

[0159] Therefore, after controlling the first expansion valve to close and the first solenoid valve to open, as Figure 19 As shown, the indoor heat exchanger acts as the evaporator, and the water-fluorine heat exchanger acts as the condenser. The refrigerant flowing out from both the indoor and outdoor heat exchangers enters the water-fluorine heat exchanger, increasing the amount of refrigerant participating in the cycle and thus enabling the production of sufficient hot water.

[0160] S304. When the indoor unit load equals the preset load, the controller controls the first expansion valve to close, the first solenoid valve to open, the third expansion valve to close, and adjusts the opening of the second expansion valve to the fifth preset opening.

[0161] Optionally, the fifth preset opening degree can be preset by the air conditioning system at the factory or obtained by the controller from other air conditioning systems; there is no limitation on this.

[0162] Understandably, when the indoor unit load equals the preset load, the first expansion valve closes and the first solenoid valve opens. Figure 20 As shown, the indoor heat exchanger acts as the evaporator, and the water-fluorine heat exchanger acts as the condenser. Because the third expansion valve is closed, only the indoor heat exchanger performs heat exchange, so all the refrigerant entering the cycle flows into the water-fluorine heat exchanger, increasing the amount of refrigerant entering the water-fluorine heat exchanger and thus producing enough hot water.

[0163] based on Figure 17 The embodiment shown in this application provides an air conditioning system that primarily utilizes the sensible heat of the refrigerant to heat the water in the water-fluoride heat exchanger, thereby producing domestic hot water at a higher temperature, reducing or even eliminating the need for other energy sources (such as electricity) for heating. Furthermore, by controlling various valves, sufficient hot water can be produced regardless of the indoor unit's load.

[0164] As can be seen, the above mainly describes the solutions provided by the embodiments of this application from a methodological perspective. To achieve the above functions, the embodiments of this application provide corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the modules and algorithm steps of the various examples described in the embodiments disclosed herein, the embodiments of this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention.

[0165] This application also provides a computer-readable storage medium including computer-executable instructions that, when run on a computer, cause the computer to execute any of the air conditioning system control methods provided in the above embodiments.

[0166] This application also provides a computer program product containing computer execution instructions, which, when run on a computer, causes the computer to execute any of the air conditioning system control methods provided in the above embodiments.

[0167] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An air conditioning system, characterized by, The air conditioning system comprises: an outdoor heat exchanger and an indoor heat exchanger; wherein one of the heat exchangers works as a condenser and the other works as an evaporator; an indoor expansion valve; wherein the indoor expansion valve is arranged on a connecting pipeline between the outdoor heat exchanger and the indoor heat exchanger; a water-fluoride heat exchanger for exchanging heat between refrigerant and water; a four-way valve for controlling the flow direction of refrigerant; when the four-way valve is in a first working state, the outdoor heat exchanger works as a condenser; when the four-way valve is in a second working state, the outdoor heat exchanger works as an evaporator; a first expansion valve and a first electromagnetic valve for controlling the flow direction of refrigerant in the system pipeline; wherein one end of the first expansion valve is connected to the four-way valve, and the other end is connected to the outdoor heat exchanger; one end of the first electromagnetic valve is connected to a gas-liquid separator, and the other end is connected to the outdoor heat exchanger in parallel with one end of the first expansion valve; a second expansion valve for controlling the flow of refrigerant to the indoor heat exchanger; a third expansion valve for controlling the flow of refrigerant to the outdoor heat exchanger; and a controller configured to: obtain an operating mode of the air conditioning system, the operating mode comprising a cooling mode, a heating mode and a hot water mode; determine whether the air conditioning system meets defrosting conditions when the operating mode is the hot water mode; wherein in the hot water mode, the four-way valve is in the first working state, the first expansion valve is in a closed state, the first electromagnetic valve is in an open state, the second expansion valve is in an open state, the third expansion valve is in a throttling state, and the indoor expansion valve is in a closed state; 2. The air conditioning system of claim 1, wherein, control the first electromagnetic valve to be closed, the first expansion valve to be opened, the third expansion valve to be slowly opened, and the indoor expansion valve to be throttled when the defrosting conditions are met.

3. The air conditioning system of claim 1, wherein, In the cooling mode, the four-way valve is in the first working state, the first expansion valve is in an open state, and the first electromagnetic valve is in a closed state. The air conditioning system further comprises: a water pump connected with the water-fluoride heat exchanger to form a water system, for providing power for the circulation of water in the water system; a temperature sensor arranged on the outdoor heat exchanger for detecting an ambient temperature; a high-pressure pressure sensor arranged on an exhaust pipeline of the compressor for detecting a high-pressure of the air conditioning system; The controller is further configured to: obtain the ambient temperature through the temperature sensor and the high-pressure of the air conditioning system through the high-pressure pressure sensor; control the second expansion valve to be throttled and the water pump to be opened when the ambient temperature is greater than or equal to a preset temperature and the high-pressure is greater than or equal to a preset threshold; or 4. The air conditioning system of claim 3, wherein, control the second expansion valve and the water pump to be closed when the ambient temperature is greater than or equal to the preset temperature and the high-pressure is less than the preset threshold. The controller is further configured to:

5. The air conditioning system according to any one of claims 1 to 4, wherein control the second expansion valve and the water pump to be closed when the ambient temperature is less than the preset temperature. The air conditioning system further comprises: An outdoor fan for dissipating heat from the outdoor heat exchanger; The controller is further configured to: In a case where the operation mode is the cooling mode and the hot water heating mode, obtain an indoor unit load; In a case where the indoor unit load is greater than a preset load, control the first expansion valve to open, the first electromagnetic valve to close, and adjust the opening degree of the second expansion valve to a first preset opening degree, the opening degree of the third expansion valve to a second preset opening degree, and the rotating speed of the outdoor fan to a preset rotating speed.

6. The air conditioning system of claim 5, wherein, The controller is further configured to: In a case where the indoor unit load is less than the preset load, control the first expansion valve to close, control the first electromagnetic valve to open, and adjust the opening degree of the second expansion valve to a third preset opening degree and the opening degree of the third expansion valve to a fourth preset opening degree.

7. The air conditioning system of claim 5, wherein, The controller is further configured to: In a case where the indoor unit load is equal to the preset load, control the first expansion valve to close, the first electromagnetic valve to open, and the third expansion valve to close, and adjust the opening degree of the second expansion valve to a fifth preset opening degree.

8. A control method of an air conditioning system, characterized by, The method is applied to the air conditioning system of any one of claims 1-7, and the method comprises: obtaining an operation mode of the air conditioning system, wherein the operation mode comprises a cooling mode, a heating mode, and a hot water heating mode; in a case where the operation mode is the hot water heating mode, determining whether the air conditioning system satisfies a defrosting condition; wherein in the hot water heating mode, a four-way valve is in a first working state, a first expansion valve is in a closed state, a first electromagnetic valve is in an open state, a second expansion valve is in an open state, a third expansion valve is in a throttling state, and an indoor expansion valve is in a closed state; in a case where the defrosting condition is satisfied, controlling the first electromagnetic valve to close, the first expansion valve to open, the third expansion valve to slowly open, and the indoor expansion valve to throttle.

9. The method of claim 8, wherein, The method further comprises: obtaining an ambient temperature and a high-pressure pressure of the air conditioning system; in a case where the ambient temperature is greater than or equal to a preset temperature and the high-pressure pressure is greater than or equal to a preset threshold, controlling the second expansion valve to throttle and a water pump to open; or in a case where the ambient temperature is greater than or equal to the preset temperature and the high-pressure pressure is less than the preset threshold, controlling the second expansion valve and the water pump to close.

10. The method according to claim 8 or 9, characterized in that, The method further comprises: in a case where the operation mode is the cooling mode and the hot water heating mode, obtaining an indoor unit load; in a case where the indoor unit load is greater than a preset load, controlling the first expansion valve to open, the first electromagnetic valve to close, and adjusting the opening degree of the second expansion valve to a first preset opening degree, the opening degree of the third expansion valve to a second preset opening degree, and the rotating speed of the outdoor fan to a preset rotating speed.

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