An air conditioning system

Abstract

The application provides an air conditioning system, and relates to the technical field of household appliances, which can recover refrigerant on the indoor unit side in time when the refrigerant leaks in a room. The air conditioning system comprises an indoor unit, an outdoor unit, a first expansion valve and a second expansion valve, and the indoor unit and the outdoor unit are connected through a refrigerant gas pipe and a refrigerant liquid pipe respectively; the first expansion valve is arranged on the refrigerant gas pipe between the indoor heat exchanger and the outdoor unit, can be opened when the indoor refrigerant leaks, so as to recover the refrigerant of the indoor unit to the outdoor unit, and can be closed after the refrigerant recovery is completed, so as to prevent the refrigerant in the outdoor unit from flowing back to the indoor unit; the second expansion valve is arranged on the refrigerant liquid pipe between the outdoor unit and the indoor expansion valve, can be closed when the indoor refrigerant leaks, so as to prevent the refrigerant of the outdoor unit from continuing to flow to the indoor unit, and the refrigerant liquid pipe between the second expansion valve and the indoor expansion valve is closed, so as to store the refrigerant between the second expansion valve and the indoor expansion valve.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of household appliances, in particular to an air conditioning system. BACKGROUND

[0002] With the improvement of people's living standards, the popularization rate of air conditioning systems is becoming more and more widespread. In the face of the large-scale popularization of air conditioning systems, air conditioning system failure problems are emerging in an endless stream.

[0003] The air conditioning device is usually composed of an indoor unit, an outdoor unit and a connection pipe. During the operation of the air conditioning, refrigerant exists in the indoor unit, the outdoor unit and the connection pipe. When the length of the connection pipe is relatively long, if refrigerant leakage is detected in the room, the refrigerant in the pipe and the indoor unit needs to be completely recovered. Since the refrigerant in the pipe has a large inventory, the indoor unit cannot completely recover the refrigerant. If the refrigerant in the connection pipe is not recovered in time, it will leak from the pipe to the indoor side, which can easily lead to a high concentration of refrigerant in the room, and there is a flammable area, which has certain safety hazards. SUMMARY

[0004] The present application provides an air conditioning system which can recover the refrigerant in the connection pipe and the indoor unit in time when refrigerant leakage is detected in the room.

[0005] To achieve the above-mentioned purpose, the embodiments of the present application adopt the following technical solutions:

[0006] In a first aspect, the present application provides an air conditioning system, which comprises an indoor unit having an indoor heat exchanger and an indoor expansion valve, an outdoor unit having a compressor, a refrigerant gas pipe and a refrigerant liquid pipe connecting the indoor unit and the outdoor unit, a first expansion valve, a second expansion valve and a controller. The first expansion valve is arranged on the refrigerant gas pipe between the indoor heat exchanger and the outdoor unit, and is used to open when the indoor refrigerant leaks, so as to recover the refrigerant of the indoor unit to the outdoor unit, and to close after the refrigerant recovery is completed, so as to prevent the refrigerant in the outdoor unit from flowing back to the indoor unit. The second expansion valve is arranged on the refrigerant liquid pipe between the outdoor unit and the indoor expansion valve, and can be closed when the indoor refrigerant leaks, so as to prevent the refrigerant of the outdoor unit from continuing to flow to the indoor unit, and to close the refrigerant liquid pipe between the second expansion valve and the indoor expansion valve, so as to store the refrigerant between the second expansion valve and the indoor expansion valve.

[0007] The controller is configured to: when it is obtained that the refrigerant leaks in the indoor, control the running mode to switch to the cooling mode, and control the indoor expansion valve and the second expansion valve to be closed and the first expansion valve to be opened; when it is detected that the compressor meets a first preset condition, control the compressor to stop and the first expansion valve to be closed; and after the compressor is controlled to stop, judge whether the refrigerant continues to leak in the indoor, if yes, start the compressor and open the first expansion valve and the indoor expansion valve.

[0008] The air conditioning system of the present application comprises a refrigerant gas pipe, a refrigerant liquid pipe, an indoor unit, an outdoor unit, a first expansion valve, a second expansion valve and a controller. The indoor unit comprises an indoor expansion valve and an indoor heat exchanger. The outdoor unit comprises a compressor. The controller is configured to: when it is obtained that the refrigerant leaks in the indoor, control the running mode to switch to the cooling mode, and control the indoor expansion valve and the second expansion valve to be closed and the first expansion valve to be opened. Thus, the high-temperature and high-pressure gaseous refrigerant flowing out of the compressor no longer flows to the indoor unit side after flowing into the outdoor unit. The refrigerant between the indoor expansion valve and the second expansion valve on the indoor unit side no longer flows, and the refrigerant between the indoor expansion valve and the first expansion valve flows to the outdoor unit side.

[0009] When it is detected that the compressor meets a first preset condition, the compressor is controlled to stop and the first expansion valve is closed. The first preset condition can be that the refrigerant between the first expansion valve and the indoor expansion valve on the indoor unit side all flows to the outdoor unit side, that is, after it is detected that the refrigerant between the first expansion valve and the indoor expansion valve all flows to the outdoor unit side, the compressor is controlled to stop. In addition, the first expansion valve is closed to disconnect the communication between the indoor unit and the outdoor unit, so as to avoid the refrigerant on the outdoor unit side from flowing back to the indoor unit side.

[0010] After the compressor is controlled to stop, it is judged whether the refrigerant continues to leak in the indoor. If no, it is confirmed that the leakage point is located between the indoor expansion valve and the first expansion valve, and at this time, the refrigerant at the leakage point has been recovered. If the refrigerant continues to leak, it is confirmed that the leakage point is located between the indoor expansion valve and the second expansion valve, then the compressor is started and the first expansion valve and the indoor expansion valve are opened, the refrigerant between the indoor expansion valve and the second expansion valve is recovered, and when it is detected that the compressor meets the first preset condition, the compressor is controlled to stop and the first expansion valve is closed, the refrigerant recovery on the indoor unit side is completed.

[0011] In this way, when the refrigerant leaks in the indoor, the refrigerant at the leakage point position can be recovered to the outdoor unit side in time, the refrigerant concentration in the room is prevented from being too high, and the safety of the air conditioning system is improved.

[0012] In some embodiments, the air conditioning system further comprises a refrigerant concentration sensor electrically connected to the controller, configured to detect the refrigerant concentration in the indoor space; before the refrigerant leakage in the indoor space is detected, the controller is further configured to: acquire the refrigerant concentration in the indoor space at the current time and the previous time, and confirm the refrigerant leakage in the indoor space if the refrigerant concentration at the current time is greater than the refrigerant concentration at the previous time; and determine whether the refrigerant continues to leak in the indoor space, comprising: determining whether the refrigerant concentration at the current time is greater than the refrigerant concentration at the previous time.

[0013] In some embodiments, the air conditioning system further comprises a first pressure sensor arranged between the indoor expansion valve and the second expansion valve, configured to detect the pressure value at the connecting pipe, wherein the connecting pipe is the refrigerant liquid pipe between the indoor expansion valve and the second expansion valve; and the determination of whether the refrigerant continues to leak in the indoor space comprises: acquiring the pressure value at the connecting pipe at the current time and the previous time; and determining whether the pressure value at the connecting pipe at the current time is less than the pressure value at the previous time.

[0014] In some embodiments, the first preset condition comprises: the running time of the compressor switching to the refrigeration mode is greater than a preset time.

[0015] In some embodiments, the air conditioning system further comprises a second pressure sensor configured to detect the discharge pressure value of the compressor; the second pressure sensor is electrically connected to the controller; the first preset condition comprises: the discharge pressure value of the compressor is greater than a first preset value; or, the air conditioning system further comprises a temperature sensor configured to detect the discharge temperature value of the compressor; the temperature sensor is electrically connected to the controller, and the first preset condition comprises: the discharge temperature value of the compressor is greater than a second preset value.

[0016] In some embodiments, the air conditioning system further comprises a third pressure sensor configured to detect the suction pressure value of the compressor; the third pressure sensor is electrically connected to the controller, and the first preset condition comprises: the suction pressure value of the compressor is less than a third preset value.

[0017] In some embodiments, the indoor expansion valve is an indoor electronic expansion valve; the starting of the compressor and the opening of the first expansion valve and the indoor expansion valve further comprise: adjusting the indoor expansion valve to a preset target opening degree according to the suction pressure value of the compressor.

[0018] In some embodiments, the air conditioning system further comprises a memory, wherein the memory stores a corresponding relationship between the suction pressure value and the preset target opening degree of the indoor expansion valve; the adjusting of the indoor expansion valve to the preset target opening degree according to the suction pressure value of the compressor comprises: the controller acquires the current suction pressure value of the compressor through the third pressure sensor; the controller acquires the preset target opening degree of the indoor expansion valve corresponding to the current suction pressure value from the memory; and the controller controls the indoor expansion valve to adjust to the preset target opening degree.

[0019] In some embodiments, the air conditioning system further comprises: an outdoor fan assembly arranged in the outdoor unit and configured to blow air to the outdoor heat exchanger; an indoor fan assembly arranged in the indoor unit and configured to blow air to the indoor heat exchanger; and a controller electrically connected to the outdoor fan assembly and the indoor fan assembly, wherein when the indoor expansion valve and the second expansion valve are both controlled to be closed, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor; and / or when the compressor is controlled to be stopped, the controller is further configured to: control the outdoor fan assembly to be turned off and control the indoor fan assembly to be turned off; and / or when the first expansion valve and the indoor expansion valve are turned on, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor.

[0020] In some embodiments, the control of the indoor fan assembly to be turned on comprises: and the indoor fan assembly is controlled to run at a first preset gear, and the control of the outdoor fan assembly to be turned on comprises: and the outdoor fan assembly is controlled to run at a second preset gear.

[0021] In some embodiments, the air conditioning system further comprises: an outdoor fan assembly arranged in the outdoor unit and configured to blow air to the outdoor heat exchanger; an indoor fan assembly arranged in the indoor unit and configured to blow air to the indoor heat exchanger; and a controller electrically connected to the outdoor fan assembly and the indoor fan assembly, wherein when the indoor expansion valve and the second expansion valve are both controlled to be closed, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor; and / or when the compressor is controlled to be stopped, the controller is further configured to: control the outdoor fan assembly to be turned off and control the indoor fan assembly to be turned off; and / or when the first expansion valve and the indoor expansion valve are turned on, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor.

[0022] In some embodiments, the air conditioning system further comprises: an outdoor fan assembly arranged in the outdoor unit and configured to blow air to the outdoor heat exchanger; an indoor fan assembly arranged in the indoor unit and configured to blow air to the indoor heat exchanger; and a controller electrically connected to the outdoor fan assembly and the indoor fan assembly, wherein when the indoor expansion valve and the second expansion valve are both controlled to be closed, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor; and / or when the compressor is controlled to be stopped, the controller is further configured to: control the outdoor fan assembly to be turned off and control the indoor fan assembly to be turned off; and / or when the first expansion valve and the indoor expansion valve are turned on, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor.

[0023] In some embodiments, the air conditioning system further comprises: an outdoor fan assembly arranged in the outdoor unit and configured to blow air to the outdoor heat exchanger; an indoor fan assembly arranged in the indoor unit and configured to blow air to the indoor heat exchanger; and a controller electrically connected to the outdoor fan assembly and the indoor fan assembly, wherein when the indoor expansion valve and the second expansion valve are both controlled to be closed, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor; and / or when the compressor is controlled to be stopped, the controller is further configured to: control the outdoor fan assembly to be turned off and control the indoor fan assembly to be turned off; and / or when the first expansion valve and the indoor expansion valve are turned on, the controller is further configured to: control the outdoor fan assembly to be turned on so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be turned on so as to improve the efficiency of evaporation of the refrigerant in the indoor unit from liquid to gas, thereby preventing liquid refrigerant from entering the compressor.

[0024] In a fifth aspect, an embodiment of the present application provides a computer program product, which can be directly loaded into a memory and contains software codes, and the computer program product can realize the method provided in the second aspect after being loaded and executed by a computer.

[0025] It should be noted that the computer instructions described above can be stored in the computer readable storage medium in whole or in part. The computer readable storage medium can be packaged together with the processor of the controller or packaged separately from the processor of the controller, and the present application does not limit this.

[0026] The beneficial effects of the second aspect to the fifth aspect described in the present application can be analyzed with reference to the beneficial effects of the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the technical solutions of the present application, and constitute a part of the specification, and are used to explain the technical solutions of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical solutions of the present application.

[0028] Figure 1 A three-dimensional structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0029] Figure 2 A structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0030] Figure 3 A circuit connection structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0031] Figure 4 A structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0032] Figure 5 A circuit connection structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0033] Figure 6 A circuit connection structural schematic diagram of an air conditioning system provided by an embodiment of the present application is provided;

[0034] Figure 7 A flowchart of a refrigerant recovery method of an air conditioning system provided by an embodiment of the present application is provided;

[0035] Figure 8 A flowchart of a refrigerant recovery method of an air conditioning system provided by an embodiment of the present application is provided;

[0036] Figure 9 A flowchart of a refrigerant recovery method of an air conditioning system provided by an embodiment of the present application is provided;

[0037] Figure 10 Fig. 1 is a schematic view of the open / close state of each component in an air conditioning system according to an embodiment of the present application;

[0038] Figure 11 Fig. 2 is a schematic view of the open / close state of each component in an air conditioning system according to an embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0041] It should be noted that: similar reference numerals and letters indicate similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0042] In the description of the present application, it should be noted that the terms “center”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “inner”, “outer”, and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms “first”, “second”, “third”, and the like are only used for differentiation in description, and cannot be understood as indicating or implying relative importance.

[0043] In addition, the terms “horizontal”, “vertical”, and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, “horizontal” only means that it is more horizontal relative to “vertical”, and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0044] In the description of the present application, it also needs to be explained that, unless otherwise explicitly specified and limited, the terms "set", "install", "connect", "connect" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] For the convenience of understanding, first, some terms or basic concepts of the technology involved in the embodiments of the present application are simply introduced and explained.

[0046] Refrigeration mode: the compressor of the air conditioning system sucks the low-temperature and low-pressure gaseous refrigerant evaporated in the evaporator into the compressor cavity, compresses it into high-temperature and high-pressure gaseous refrigerant, and enters the condenser. The high-temperature and high-pressure gaseous refrigerant is condensed into high-temperature and high-pressure liquid refrigerant in the condenser, and then becomes low-temperature and low-pressure liquid refrigerant after throttling by a throttling element such as a capillary, and enters the evaporator to evaporate, and finally returns to the compressor, thereby completing the entire refrigeration cycle. Among them, the outdoor heat exchanger in the refrigeration mode is used as a condenser, and the indoor heat exchanger is used as an evaporator.

[0047] Refrigerant: a substance that easily absorbs heat to become a gas and easily releases heat to become a liquid. In the air conditioning system, heat energy is transferred through the evaporation and condensation of the refrigerant to produce a refrigeration effect.

[0048] Superheat: the difference between the actual temperature of the refrigerant at the outlet of the evaporator and the corresponding saturated temperature at this pressure, that is, the difference between the evaporator outlet temperature and the evaporation temperature.

[0049] Expansion valve: composed of a valve body and a coil, used for throttling and pressure reduction and flow regulation. The expansion valve in the air conditioning system can make the liquid refrigerant at high temperature and high pressure pass through the throttling to become low-temperature and low-pressure wet steam, and then the refrigerant absorbs heat in the evaporator to achieve the refrigeration effect, and the valve flow is controlled by the change of the superheat at the outlet of the evaporator.

[0050] In the present application, the air conditioning system uses a compressor, a condenser, an expansion valve, an evaporator and a four-way valve as a refrigerant circulation loop to perform the refrigeration cycle of the air conditioning system. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the air that has been adjusted and heat exchanged.

[0051] The compressor compresses the refrigerant gas at high temperature and high pressure and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

[0052] The expansion valve expands the high-temperature, high-pressure liquid refrigerant condensed in the condenser to a lower-pressure liquid. The evaporator evaporates the refrigerant expanded in the electronic expansion valve and returns the low-temperature, low-pressure refrigerant gas to the compressor. The evaporator achieves cooling by utilizing the latent heat of evaporation to exchange heat with the material being cooled. Throughout this cycle, the air conditioning system regulates the temperature of the indoor space.

[0053] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioning system functions as a heater in heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioning system functions as a cooler in cooling mode.

[0054] Figure 1 FIG. 1 shows a schematic diagram of a three-dimensional structure of an air conditioning system provided in an embodiment of the present application. Figure 1 As shown, the air conditioning system 100 includes: an indoor unit 10, an outdoor unit 20, a refrigerant pipeline 30, a first expansion valve 01, a second expansion valve 04 and a controller 40 ( Figure 1 The refrigerant pipeline 30 includes a refrigerant gas pipe and a refrigerant liquid pipe, and the indoor unit 10 and the outdoor unit 20 are connected via the refrigerant gas pipe and the refrigerant liquid pipe, respectively.

[0055] The first expansion valve is located on the refrigerant gas pipe between the indoor heat exchanger and the outdoor unit. It opens in the event of an indoor refrigerant leak, allowing refrigerant from the indoor unit to be recycled to the outdoor unit. It closes after refrigerant recycling is complete to prevent refrigerant from the outdoor unit from flowing back into the indoor unit. The second expansion valve is located on the refrigerant liquid pipe between the outdoor unit and the indoor expansion valve. It closes in the event of an indoor refrigerant leak, preventing refrigerant from the outdoor unit from continuing to flow to the indoor unit. It also seals the refrigerant liquid pipe between the second expansion valve and the indoor expansion valve, allowing the refrigerant to be stored between the second expansion valve and the indoor expansion valve.

[0056] Among them, such as Figure 1 As shown, the indoor unit 10, the second expansion valve 04, the outdoor unit 20, and the first expansion valve 01 are connected in series in sequence through the refrigerant pipeline 30. The refrigerant pipeline 30 can also be called a circulation pipeline. The circulation pipeline connects the indoor unit 10 and the outdoor unit 20 to form a circulation loop.

[0057] Figure 2 A schematic diagram of the structure of an air conditioning system provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, the indoor unit 10 may include: an indoor heat exchanger 02 and an indoor expansion valve 03. Figure 3 A schematic diagram of a circuit connection structure of an air conditioning system provided in an embodiment of the present application is shown. Figure 3As shown, the first expansion valve 01, the indoor heat exchanger 02, the indoor expansion valve 03 and the second expansion valve 04 are electrically connected with the controller 40.

[0058] As shown, the first expansion valve 01, the indoor heat exchanger 02, the indoor expansion valve 03 and the second expansion valve 04 can be connected in series through the refrigerant pipeline 30. That is, one end of the first expansion valve 01 is connected with one end of the indoor heat exchanger 02 through the refrigerant pipeline 30, the other end of the indoor heat exchanger 02 is connected with one end of the indoor expansion valve 03 through the refrigerant pipeline 30, and the other end of the indoor expansion valve 03 is connected with one end of the second expansion valve 04 through the refrigerant pipeline 30.

[0059] As shown, the first expansion valve 01, the indoor heat exchanger 02, the indoor expansion valve 03 and the second expansion valve 04 can be connected in series through the refrigerant pipeline 30. That is, one end of the first expansion valve 01 is connected with one end of the indoor heat exchanger 02 through the refrigerant pipeline 30, the other end of the indoor heat exchanger 02 is connected with one end of the indoor expansion valve 03 through the refrigerant pipeline 30, and the other end of the indoor expansion valve 03 is connected with one end of the second expansion valve 04 through the refrigerant pipeline 30. Figure 2 As shown, the outdoor unit 20 provided by the embodiment of the present application can include: a four-way valve 21, a compressor 22, an outdoor heat exchanger 23, and an outdoor expansion valve 24. Figure 3 As shown, the four-way valve 21, the compressor 22, the outdoor heat exchanger 23, and the outdoor expansion valve 24 are electrically connected with the controller 40.

[0060] As shown, the four-way valve 21, the compressor 22, the outdoor heat exchanger 23, and the outdoor expansion valve 24 are electrically connected with the controller 40.

[0061] As shown, the four-way valve 21, the compressor 22, the outdoor heat exchanger 23, and the outdoor expansion valve 24 are electrically connected with the controller 40.

[0062] As shown, the four-way valve 21, the compressor 22, the outdoor heat exchanger 23, and the outdoor expansion valve 24 are electrically connected with the controller 40.

[0063] Exemplary, when the air conditioning system 100 is in cooling mode, the compressor 22 starts, the first expansion valve 01, the indoor expansion valve 03, the second expansion valve 04, the outdoor expansion valve 24 are opened, the first interface A and the second interface B are communicated, the third interface C and the fourth interface D are communicated; the high temperature and high pressure gaseous refrigerant discharged by the compressor 22 flows to the outdoor heat exchanger 23 through the four-way valve 21, the high temperature and high pressure gaseous refrigerant is condensed into medium temperature and high pressure supercooled liquid refrigerant at the outdoor heat exchanger 23, the medium temperature and high pressure supercooled liquid refrigerant passes through the outdoor expansion valve 24, the second expansion valve 04, the indoor expansion valve 03 and the indoor heat exchanger 02 in turn, the medium temperature and high pressure supercooled liquid refrigerant is throttled into low temperature and low pressure liquid refrigerant when passing through the second expansion valve 04 and the indoor expansion valve 03, the low temperature and low pressure liquid refrigerant evaporates into low temperature and low pressure gaseous refrigerant when passing through the indoor heat exchanger 02 (the refrigerant evaporates and absorbs heat, thereby reducing the indoor temperature); the low temperature and low pressure gaseous refrigerant flows into the compressor 22 after passing through the four-way valve 21, thus completing the circulation of the refrigerant in the cooling mode of the air conditioning system 100.

[0064] Exemplary, when the air conditioning system 100 is in cooling mode, the compressor 22 starts, the first expansion valve 01, the indoor expansion valve 03, the second expansion valve 04, the outdoor expansion valve 24 are opened, the first interface A and the fourth interface D are communicated, the second interface B and the third interface C are communicated; when the high temperature and high pressure gaseous refrigerant discharged by the compressor 22 passes through the four-way valve 21, it passes through the first expansion valve 01 and the indoor heat exchanger 02 in turn, the high temperature and high pressure gaseous refrigerant is condensed into medium temperature and high pressure supercooled liquid refrigerant at the indoor heat exchanger 02 (the refrigerant condenses and releases heat, thereby increasing the indoor temperature), the medium temperature and high pressure supercooled liquid refrigerant passes through the indoor expansion valve 03, the second expansion valve 04 and the outdoor expansion valve 24 in turn, the medium temperature and high pressure supercooled liquid refrigerant is throttled into low temperature and low pressure liquid refrigerant under the action of the outdoor expansion valve 24, the low temperature and low pressure liquid refrigerant evaporates into low temperature and low pressure gaseous refrigerant when passing through the outdoor heat exchanger 23; the low temperature and low pressure gaseous refrigerant flows into the compressor 22 after passing through the four-way valve 21, thus completing the circulation of the refrigerant in the heating mode of the air conditioning system 100.

[0065] In the embodiments shown in the present application, the controller 40 refers to a device that can generate operation control signals according to instruction operation codes and timing signals to instruct the air conditioning system 100 to execute control instructions. Exemplarily, the controller 40 can be a central processing unit (CPU), a general processor network processor (NP), a digital signal processing (DSP), a programmable logic device (PLD), a microprocessor, a microcontroller 40, or any combination thereof. The controller 40 can also be other devices with processing functions, such as circuits, devices, or software modules, and the embodiments of the present application do not make any limitation thereto.

[0066] In some embodiments, the controller 40 can be a microcontroller unit (MCU). The MCU, also known as a single chip microcomputer or a single-chip microprocessor, is a central processing unit (CPU) with reduced frequency and specifications, and integrates memory, timers, USB, A / D conversion, UART, PLC, DMA, and even LCD driving circuits on a single chip to form a chip-level computer for different application scenarios.

[0067] In addition, the controller 40 can be used to control the operation of various components inside the air conditioning system 100, so that the various components of the air conditioning system 100 operate to achieve the predetermined functions of the air conditioning system 100.

[0068] Exemplarily, the controller 40 can execute the following control instructions: when it is detected that the refrigerant leaks in the indoor, the operation mode is switched to the cooling mode, and the indoor expansion valve 03 and the second expansion valve 04 are both closed, and the first expansion valve 01 is opened; when it is detected that the compressor 22 meets the first preset condition, the compressor 22 is stopped, and the first expansion valve 01 is closed; after the compressor 22 is stopped, it is determined whether the refrigerant continues to leak in the indoor, if yes, the compressor 22 is started, and the first expansion valve 01 and the indoor expansion valve 03 are opened; when it is detected that the compressor 22 meets the first preset condition, the compressor 22 is stopped, and the first expansion valve 01 is closed.

[0069] The air conditioning system 100 of the present application includes a refrigerant pipeline 30, an indoor unit 10, an outdoor unit 20, and a controller 40. The indoor unit 10 includes a first expansion valve 01, an indoor heat exchanger 02, an indoor expansion valve 03, and a second expansion valve 04. The outdoor unit 20 includes a four-way valve 21, a compressor 22, an outdoor heat exchanger 23, and an outdoor expansion valve 24. The controller 40 is configured to, upon detecting a refrigerant leak indoors, switch the operating mode to cooling mode, close both the indoor expansion valves 03 and 04, and open the first expansion valve 01. This prevents the high-temperature, high-pressure gaseous refrigerant from the compressor 22 from flowing into the outdoor unit 20 and then no longer flowing toward the indoor unit 10. The refrigerant between the indoor expansion valves 03 and 04 no longer flows, and the refrigerant between the indoor expansion valves 03 and 01 flows toward the outdoor unit 20.

[0070] When it is detected that the compressor 22 meets the first preset condition, the compressor 22 is controlled to stop and the first expansion valve 01 is closed; the first preset condition can be the state of the compressor 22 after the refrigerant between the first expansion valve 01 and the indoor expansion valve 03 flows to the outdoor unit 20 side; that is, after it is detected that the refrigerant between the first expansion valve 01 and the indoor expansion valve 03 flows to the outdoor unit 20 side, the compressor 22 is controlled to stop. In addition, the first expansion valve 01 is closed to disconnect the connection between the indoor unit 10 and the outdoor unit 20, so as to prevent the refrigerant on the outdoor unit 20 side from flowing back to between the first expansion valve 01 and the indoor heat exchanger 02.

[0071] After controlling the compressor 22 to stop, determine whether the refrigerant continues to leak indoors. If it is not leaking, confirm that the leakage point is between the indoor expansion valve 03 and the first expansion valve 01. At this time, the refrigerant at the leakage point has been recovered; if the refrigerant continues to leak, confirm that the leakage point is between the indoor expansion valve 03 and the second expansion valve 04, then start the compressor 22, and open the first expansion valve 01 and the indoor expansion valve 03 to recover the refrigerant between the indoor expansion valve 03 and the second expansion valve 04. When it is detected that the compressor 22 meets the first preset condition, control the compressor 22 to stop, and close the first expansion valve 01, and the refrigerant recovery on the indoor unit 10 side is completed.

[0072] In this way, when the refrigerant leaks indoors, the refrigerant at the leak point can be promptly recovered to the outdoor unit 20 side, thereby avoiding excessive refrigerant concentration in the room and improving the safety of the air-conditioning system 100.

[0073] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes a first stop valve 51 and a second stop valve 52 , through which the circulation pipelines of the indoor unit 10 and the outdoor unit 20 are connected.

[0074] In some embodiments, as Figure 4As shown, the air conditioning system 100 further includes: a first refrigerant concentration sensor 53, which can be set in an indoor room. Figure 5 As shown, the first refrigerant concentration sensor can be electrically connected to the controller 40 to detect the refrigerant concentration in the room.

[0075] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes: a second refrigerant concentration sensor 54, which can be set in the indoor unit 10. Figure 5 As shown, the second refrigerant concentration sensor 54 may also be electrically connected to the controller 40 to detect the refrigerant concentration in the indoor unit 10 .

[0076] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes: a first pressure sensor 55, which is arranged between the indoor expansion valve 03 and the second expansion valve 04 and is used to detect the pressure value at the connecting pipe, which is the refrigerant pipe 30 between the indoor expansion valve 03 and the second expansion valve 04. Figure 5 As shown, the first pressure sensor 55 may also be electrically connected to the controller 40 .

[0077] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes: a second pressure sensor 56, which is arranged at the outlet F of the compressor 22 and is used to detect the exhaust pressure value of the compressor 22. Figure 5 As shown, the second pressure sensor 56 is electrically connected to the controller 40 .

[0078] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes: a third pressure sensor 57, which is arranged at the inlet E of the compressor 22 and is used to detect the suction pressure value of the compressor 22. Figure 5 As shown, the third pressure sensor 57 may also be electrically connected to the controller 40 .

[0079] In some embodiments, as Figure 4 As shown, the air conditioning system 100 further includes a temperature sensor 58, which is disposed at the outlet F of the compressor 22. The temperature sensor 58 is used to detect the exhaust temperature of the compressor 22. Figure 5 As shown, the temperature sensor 58 may also be electrically connected to the controller 40 .

[0080] In some embodiments, the indoor expansion valve 03 is an indoor electronic expansion valve, the first expansion valve 01 is a first electronic expansion valve, and the second expansion valve 04 is a third electronic expansion valve.

[0081] In some embodiments, as shown in Figure 5 The air conditioning system 100 further includes a memory 59 electrically connected to the controller 40, and the memory 59 stores a corresponding relationship between the suction pressure value and the preset target opening degree of the indoor expansion valve 03.

[0082] In some embodiments, as shown in Figure 4 The air conditioning system 100 further includes an outdoor fan assembly 60 and an indoor fan assembly 61. The outdoor fan assembly is arranged in the outdoor unit, and the indoor fan assembly is arranged in the indoor unit. As shown in Figure 5 The indoor fan assembly 61 and the outdoor fan assembly 60 are electrically connected to the controller 40. The indoor fan assembly 60 is used to blow air to the outdoor heat exchanger 23, and the indoor fan assembly 61 is used to blow air to the indoor heat exchanger 02.

[0083] Figure 6 A circuit connection schematic diagram of an air conditioning system provided by an embodiment of the present application is shown. In some embodiments, as shown in Figure 6 The indoor unit 10 of the air conditioning system 100 can include a remote controller 62 electrically connected to the controller 40. The remote controller 62 has a function of communicating with the controller 40, for example, using infrared rays or other communication methods. A user can control the air conditioning system 100 through the remote controller 62 to realize the interaction between the user and the air conditioning system 100.

[0084] In some embodiments, as shown in Figure 6 The air conditioning system 100 can further include a communicator 63 electrically connected to the controller 40, and the communicator 63 is used to establish a communication connection with a server. The communicator 63 can include a radio frequency (RF) module, a cellular module, a wireless fidelity (WIFI) module, and a GPS module, etc. Taking the RF module as an example, the RF module can be used for receiving and sending signals, in particular, sending the received information to the controller 40 for processing, and sending the signals generated by the controller 40. Generally, the RF circuit can include but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc.

[0085] In some embodiments, the air conditioning system 100 can also send its operation data to the server through the communicator 63, so that the server calculates the operation parameters of each component of the multi-connected air conditioning system 100 in the working process according to the data of the air conditioning system 100, and then sends the calculated operation parameters to the air conditioning system 100. The controller 40 controls each component in the air conditioning system 100 to work according to the operation parameters calculated by the server.

[0086] The server can be a single server, or can also be a server cluster composed of multiple servers. In some embodiments, the server cluster can also be a distributed cluster. In some embodiments, the server can also be a cloud server, and the specific type of the server is not limited in the embodiments of the present application.

[0087] In some embodiments, the memory 59 can be used to store software programs and data. The controller 40 executes various functions of the air conditioning system 100 and data processing by running the software programs or data stored in the memory 59. The memory 59 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device. The memory 59 stores an operating system that enables the air conditioning system 100 to operate. The memory 59 can store an operating system and various application programs in the present application, and can also store codes for executing a refrigerant recovery method of an air conditioning system 100 provided in the embodiments of the present application.

[0088] The embodiments provided in the present application will be specifically introduced below in conjunction with the accompanying drawings of the specification.

[0089] As shown in Figure 7 The present application provides a refrigerant recovery method of an air conditioning system, which can be applied to the controller in the above-mentioned air conditioning system. The refrigerant recovery method of the air conditioning system can include the following steps:

[0090] S101, when the controller acquires that the refrigerant leaks indoors, the controller controls the operation mode to switch to the refrigeration mode, and controls the indoor expansion valve and the second expansion valve to be closed and the first expansion valve to be opened.

[0091] In the refrigeration mode, the first interface and the second interface of the four-way valve are in communication, the third interface and the fourth interface of the four-way valve are in communication, and the compressor is started to operate at a preset frequency.

[0092] In some embodiments, the indoor expansion valve, the second expansion valve and the first expansion valve are all electronic expansion valves, and the opening degree of the indoor expansion valve and the second expansion valve can be adjusted to 0 pls, i.e., the indoor expansion valve and the second expansion valve are in a fully closed state. In this way, the refrigerant pipeline between the indoor expansion valve and the second expansion valve is a closed pipeline, and the refrigerant in the refrigerant pipeline between the indoor expansion valve and the second expansion valve can be stored.

[0093] In some embodiments, the opening degree of the first expansion valve can be adjusted to a fully open state, so that the maximum refrigerant flow area can be achieved, the maximum recovery of refrigerant can be achieved, and the time for refrigerant recovery can be reduced.

[0094] It can be understood that when the controller obtains that the refrigerant leaks indoors, the operating mode of the air conditioning system can be a heating mode, a dehumidification mode, etc.

[0095] Therefore, as Figure 8 indicated, the controller controlling the operating mode to switch to the cooling mode can include the following steps:

[0096] S1011, the controller determines whether the current operating mode is a cooling mode.

[0097] In a possible implementation, the controller can obtain the operating parameter information of the air conditioning system through the memory, and the operating parameter information includes: the current operating mode of the air conditioning system, so as to determine whether the current operating mode is a cooling mode.

[0098] In another possible implementation, the controller can also determine the current operating mode according to the connection state of the four-way valve interface and the operating frequency of the compressor, so as to determine whether the current operating mode is a cooling mode.

[0099] S1012, the current operating mode stops operating.

[0100] In step S1011, if the determination is no, the step S1012 is performed.

[0101] S1013, the controller controls the operating mode to operate in a cooling mode.

[0102] In step S1011, if the determination is no, after the execution of S1012, the step S1013 is continued to be executed, so that the operating mode of the air conditioning system is switched to the cooling mode. In step S1011, if the determination is yes, the step S1013 is directly executed, and the air conditioning system continues to operate in the cooling mode.

[0103] In some embodiments, when the indoor expansion valve and the second expansion valve are both closed, the controller can also control the indoor fan assembly to be turned on to evaporate the indoor-side refrigerant from liquid to gas as much as possible, to avoid liquid refrigerant from entering the compressor and causing liquid hammer problem, and to affect the reliability of the compressor. In this way, the heat exchange efficiency between the indoor heat exchanger and the indoor air can be improved, thereby increasing the flow rate of the refrigerant between the indoor heat exchanger and the indoor expansion valve, reducing the refrigerant recovery time, and thus reducing the refrigerant leakage.

[0104] In a possible implementation, the controller controlling the indoor fan assembly to be turned on can include: the controller controlling the indoor fan assembly to operate at a first preset gear. The first preset gear is a gear preset for the air conditioning system.

[0105] For example, the first preset gear can be the highest gear that the indoor fan assembly can reach, i.e., the gear with the largest air output per unit time. In this way, the refrigerant can be quickly recovered, and the refrigerant leakage can be reduced.

[0106] In other embodiments, when the indoor expansion valve and the second expansion valve are both closed, the controller can also control the outdoor fan assembly to be turned on, so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve.

[0107] In a possible implementation, the controller controlling the outdoor fan assembly to be turned on can include: the controller controlling the outdoor fan assembly to operate at a second preset gear. The second preset gear is a gear preset for the air conditioning system.

[0108] For example, the second preset gear can be the highest gear that the outdoor fan assembly can reach, i.e., the gear with the largest air output per unit time. In this way, the pressure change in the refrigerant pipe between the compressor and the outdoor heat exchanger during refrigerant recovery can be avoided, and the normal operation of the air conditioning system can be ensured.

[0109] The second preset gear can be the same as or different from the first preset gear, which is not limited in the present application.

[0110] In addition, before the step S101, as shown in Figure 9 the refrigerant recovery method of the air conditioning system can further include:

[0111] S100, the controller obtains the refrigerant concentrations of the indoor at the current time and the previous time, and if the refrigerant concentration at the current time is greater than the refrigerant concentration at the previous time, it is determined that the refrigerant leaks in the indoor.

[0112] It can be understood that if the refrigerant concentration at the current time is less than or equal to the refrigerant concentration at the previous time, the controller does not perform an action, and the refrigerant concentration of the indoor at the current time and the previous time can continue to be obtained.

[0113] In a possible implementation, the controller obtains the refrigerant concentration of the indoor according to the refrigerant concentration sensor every interval of a preset time length, and the current time and the previous time are interval of the preset time length.

[0114] For example, if the controller obtains the refrigerant concentration of the indoor every 30S, the current time and the previous time are interval of 30S.

[0115] The preset time length can also be 5S, 10S, etc., which is not limited in the application.

[0116] S102, the controller controls the compressor to stop and closes the first expansion valve when detecting that the compressor meets the first preset condition.

[0117] The closing of the first expansion valve can be adjusting the first expansion valve to 0Pls, that is, the full-closed state.

[0118] It can be understood that the first preset condition is the state of the compressor when the refrigerant in the indoor unit side communicated with the outdoor unit side all flows to the outdoor unit side. When the compressor is controlled to stop, the first expansion valve is closed to disconnect the communication between the indoor unit and the outdoor unit, so as to avoid the refrigerant on the outdoor unit side from flowing back to the indoor unit side.

[0119] The first preset condition can include the following:

[0120] (1) The running time of the compressor switching to the refrigeration mode is greater than a preset time.

[0121] The preset time can be a time set in advance. For example, the preset time can be 20min, 25min, etc., which is not limited in the application.

[0122] For example, when the compressor runs for 20min after switching to the refrigeration mode, the compressor stops running and the first expansion valve is closed.

[0123] (2) The discharge pressure value of the compressor is greater than a first preset value.

[0124] Similarly, the first preset value is a value set in advance. For example, the first preset value can be 3.7Mpa, 3.8Mpa, etc., which is not limited in the application.

[0125] For example, if the (current) discharge pressure value of the compressor is 3.8Mpa and the first preset value is 3.7Mpa, the compressor stops running and the first expansion valve is closed.

[0126] (3) the discharge temperature value of the compressor is greater than a second preset value.

[0127] The second preset value can also be a preset value. For example, the second preset value can be 105°C, 100°C, etc. The application does not limit this.

[0128] For example, if the second preset value is 105°C and the (current) discharge temperature of the compressor is 108°C, the compressor stops running and the first expansion valve is closed.

[0129] (4) the suction pressure value of the compressor is less than a third preset value.

[0130] The third preset value can also be a preset value. For example, the third preset value can be 0.1 MPa, 0.08 MPa, etc. The application does not limit this.

[0131] For example, the third preset value can be 0.1 MPa, and the (current) suction pressure of the compressor is 0.08 MPa. Then the compressor stops running and the first expansion valve is closed.

[0132] Among them, one of the above four judgment conditions is met to end the recovery process.

[0133] The determination of the above-mentioned preset time, first preset value, second preset value, and third preset value can be obtained by experiment. Under the current conditions, when the refrigerant in the indoor unit side connected to the outdoor unit side flows to the outdoor unit side, the running time of the compressor switching to the refrigeration mode at this time can be used as the preset time; the discharge pressure value of the compressor at this time can be used as the first preset value; the discharge temperature value of the compressor at this time can be used as the second preset value; and the suction pressure value of the compressor at this time can be used as the third preset value.

[0134] In some embodiments, when the compressor is controlled to stop, the controller is further configured to control the outdoor fan assembly to be closed. In this way, the loss of the air conditioning system is saved.

[0135] In some other embodiments, when the compressor is controlled to stop, the controller is further configured to control the indoor fan assembly to be closed. In this way, the loss of the air conditioning system is saved.

[0136] S103, after the controller controls the compressor to stop, it is judged whether the refrigerant continues to leak in the indoor.

[0137] In some embodiments, judging whether the refrigerant continues to leak in the indoor can include the following steps:

[0138] Step 1, the controller judges whether the current refrigerant concentration is greater than the refrigerant concentration at the previous time.

[0139] That is, the controller acquires the refrigerant concentration in the room according to the refrigerant concentration sensor, and determines whether the refrigerant concentration at the current time is greater than the refrigerant concentration at the previous time.

[0140] The step 1 can refer to the description of S100, and will not be described here.

[0141] In some embodiments, determining whether the refrigerant continues to leak in the room can further include the following steps:

[0142] Step 2, acquiring the pressure values at the current time and the previous time at the connection pipe;

[0143] Step 3, determining whether the pressure value at the current time at the connection pipe is less than the pressure value at the previous time.

[0144] It can be understood that the refrigerant in the refrigerant pipeline between the indoor expansion valve and the first expansion valve has been emptied, and if the refrigerant continues to leak in the room, the leakage point is located at the connection pipe.

[0145] This embodiment is to determine whether the refrigerant continues to leak in the room according to whether the pressure value at the connection pipe changes.

[0146] S104, if yes, the controller starts the compressor, and opens the first expansion valve and the indoor expansion valve.

[0147] It can be understood that if no, it is confirmed that the refrigerant leakage point is located in the refrigerant pipeline between the indoor expansion valve and the first expansion valve, the refrigerant at the leakage point is recovered, and the refrigerant at the leakage point no longer continues to leak,

[0148] If yes, it is determined that the refrigerant leakage point is located at the connection pipe, and the refrigerant at the connection pipe needs to be recovered to the outdoor unit side.

[0149] In some embodiments, when the first expansion valve and the indoor expansion valve are opened, the controller is further configured to control the indoor fan assembly to be opened to evaporate the refrigerant on the indoor side from liquid state to gas state as much as possible, avoid liquid refrigerant from entering the compressor, and avoid liquid strike problem, and affect the reliability of the compressor. In some other embodiments, when the indoor fan assembly is controlled to be opened and the indoor fan assembly is controlled to operate at the first preset gear, refer to the description in S1013, and will not be described here.

[0150] In some embodiments, when the first expansion valve and the indoor expansion valve are opened, the controller is further configured to: control the outdoor fan assembly to be turned on, so that the refrigerant in the refrigerant gas pipe between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve. In other embodiments, when the outdoor fan assembly is controlled to be turned on and the outdoor fan assembly is controlled to operate at the second preset gear, the description in S1013 above can be referred to, and the present application will not be repeated here.

[0151] In some embodiments, the opening of the first expansion valve can be adjusting the opening degree of the first expansion valve to a fully open state, so that the refrigerant pipe has better flow capacity.

[0152] In addition, the frequency of the compressor can be gradually increased after the compressor is started until the operating frequency of the compressor reaches the preset operating frequency, and the compressor continues to operate at the preset operating frequency. In this way, the operation of the compressor is stable, and the service life of the compressor can be improved.

[0153] In the refrigeration operation, the opening degree of the indoor expansion valve mainly controls the superheat degree of the indoor unit. The indoor unit always ensures a certain superheat degree to prevent the occurrence of compressor liquid return problems. At the same time, the opening degree of the indoor expansion valve causes a certain pressure difference between the indoor and outdoor sides, which constitutes the operation of the entire refrigeration system. In the normal refrigeration mode, the opening degree of the indoor expansion valve is small. For example, if the maximum opening degree of the indoor expansion valve is 200 Pls, the opening degree of the indoor expansion valve in the normal refrigeration mode can be 10% of the full opening state of the expansion valve, i.e. the opening degree of the indoor expansion valve is 20 Pls. At this time, the flow area of the refrigerant pipe is small, and the amount of refrigerant flowing into the indoor unit from the pipe is small.

[0154] Since the opening degree of the indoor expansion valve controls the superheat degree of the refrigerant, in order to avoid liquid strike of the compressor (i.e. insufficient evaporation of liquid refrigerant at the outdoor unit, resulting in liquid refrigerant flowing into the compressor), the opening degree of the indoor expansion valve should not be too large, and in order to ensure that the internal refrigerant at the closed pipe recovers quickly, the opening degree of the indoor expansion valve should not be too small. Therefore, in some embodiments of the present application, the step S104 of "opening the indoor expansion valve" can further include: adjusting the indoor expansion valve to a preset target opening degree according to the suction pressure value of the compressor.

[0155] It can be understood that when the suction pressure value is high, the amount of refrigerant in the indoor unit is large, and the opening degree of the indoor expansion valve can remain unchanged. When the suction pressure decreases, the amount of refrigerant remaining in the indoor unit is small, and the opening degree of the indoor expansion valve can be increased.

[0156] In a possible implementation, the memory stores a preset target opening degree of the indoor expansion valve corresponding to the suction pressure value, and the suction pressure value can be inversely proportional to the preset target opening degree of the indoor expansion valve.

[0157] For example, the preset target opening degree of the indoor expansion valve corresponding to the suction pressure value can be as shown in Table 1.

[0158] Table 1

[0159]

[0160] The controller can obtain the current suction pressure value of the compressor through the third pressure sensor, obtain the preset target opening degree of the indoor expansion valve corresponding to the current pressure value from the memory, and control the indoor expansion valve to adjust to the preset target opening degree.

[0161] For example, if the controller obtains the current suction pressure value of the compressor through the third pressure sensor as 0.5 Mpa, and adjusts the opening degree of the first expansion valve to 800 pls according to Table 1, the flow area of the pipeline is increased, the amount of refrigerant in the connecting pipe is supplemented to the indoor unit side, and then the refrigerant is sucked into the outdoor unit side by the compressor; after a period of time, the controller obtains the current suction pressure value of the compressor through the third pressure sensor as 0.49 Mpa, and adjusts the opening degree of the first expansion valve to 1100 pls. In this way, as the suction pressure decreases, the opening degree of the indoor expansion valve gradually increases, so that the refrigerant in the connecting pipe is recovered to the outdoor side, to ensure that the compressor will not cause liquid hammering due to liquid return.

[0162] In a possible implementation, when adjusting the opening degree of the indoor expansion valve, the opening degree of the indoor expansion valve can be gradually increased until the opening degree of the indoor expansion valve reaches the preset target opening degree.

[0163] For example, if the preset target opening degree of the indoor expansion valve is 200 pls, the controller can gradually increase the opening degree of the indoor expansion valve at a speed of 20 pls / s, and the adjustment time is 10 s.

[0164] S105, the controller controls the compressor to stop and closes the first expansion valve when detecting that the compressor meets the first preset condition.

[0165] Wherein, it can be understood that after the indoor expansion valve and the first expansion valve are both opened, the refrigerant in the refrigerant pipeline communicated with the outdoor unit side of the indoor unit side exists again, thereby causing the compressor to no longer satisfy the preset condition in the step S102. Therefore, the compressor is started, and the first expansion valve and the indoor expansion valve are opened to recover the refrigerant in the indoor unit side to the outdoor unit side. When the compressor satisfies the first preset condition, it indicates that the refrigerant in the indoor unit side is completely recovered, and thus the compressor is controlled to stop. The first expansion valve is closed to avoid the refrigerant in the outdoor unit side from flowing back to the indoor unit side.

[0166] In some embodiments, in the step S105, when the controller controls the compressor to stop, the controller also controls the outdoor fan assembly and the indoor fan assembly to be closed.

[0167] Figure 10 and Figure 11 all show the opening and closing state diagrams of various components in an air conditioning system provided by the embodiments of the present application, wherein, Figure 10 is the opening and closing state diagram of components with the leakage point located at the connecting pipeline, and in Figure 10 , when the controller obtains the refrigerant leakage, the controller controls the compressor, the first expansion valve, the indoor expansion valve and the second expansion valve to be in the 0 point state; when the compressor satisfies the first preset condition, the controller controls the compressor, the first expansion valve, the indoor expansion valve and the second expansion valve to be in the M point state; when it is determined that the refrigerant no longer leaks in the indoor unit, the controller controls the compressor, the first expansion valve, the indoor expansion valve and the second expansion valve to be in the N1 point state.

[0168] In Figure 11 , the 0 point and the M point are the same as the 0 point and the M point in Figure 10 , and the present application will not be described again. When it is determined that the refrigerant continues to leak in the indoor unit, the controller controls the compressor, the first expansion valve, the indoor expansion valve and the second expansion valve to be in the N2 point state; when the compressor again satisfies the first preset condition, the controller controls the compressor, the first expansion valve, the indoor expansion valve and the second expansion valve to be in the P point state.

[0169] It can be seen that the above mainly introduces the scheme provided by the embodiments of the present application from the perspective of the method. In order to realize the above functions, the embodiments of the present application provide the corresponding hardware structure and / or software module for executing each function. Those skilled in the art should easily realize that the modules and algorithm steps of the examples described in combination with the embodiments disclosed in the present text can be realized in the form of hardware or the combination of hardware and computer software. Whether a certain function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical scheme. Professional technicians can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0170] The embodiments of the present application can divide the functions of the controller into function modules according to the above method examples. For example, each function module can be divided according to each function, or two or more functions can be integrated into one processing module. The integrated module can be realized in the form of hardware or in the form of a software function module. Optionally, the division of the modules in the embodiments of the present application is illustrative, and is only a logical function division. In actual implementation, another division manner can be used.

[0171] The embodiments of the present application also provide a computer readable storage medium, including computer execution instructions, which, when running on a computer, cause the computer to execute any one of the refrigerant recovery methods of the air conditioning system provided by the above embodiments.

[0172] The embodiments of the present application also provide a computer program product including computer execution instructions, which, when running on a computer, cause the computer to execute any one of the refrigerant recovery methods of the air conditioning system provided by the above embodiments.

[0173] In the above embodiments, the implementation can be realized by software, hardware, firmware or any combination thereof, in whole or in part. When implemented by software, the implementation can be realized in the form of a computer program product in whole or in part. The computer program product includes one or more computer execution instructions. When the computer execution instructions are loaded and executed on a computer, the flow or function according to the embodiments of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. The computer execution instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, the computer execution instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode. The computer readable storage medium can be any available medium that can be accessed by a computer or data storage device including one or more servers, data centers, etc. integrated with the medium. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a solid state disk (SSD)), etc.

[0174] Although the application has been described in connection with the embodiments thereof with reference to the various drawings, it will be apparent to those of ordinary skill in the art that variations in the embodiments can be used and that it is not intended to limit the application to the particular form described. From the above discussion and illustrations, one skilled in the art will readily develop variations in the embodiments without departing from the spirit and scope of the application. Accordingly, the application is not limited by the specific examples described herein, but only by the claims that follow, the intent being to cover all modifications and equivalents falling within the spirit and scope of the application. The specification and drawings are, accordingly to be regarded as illustrative rather than restrictive.

[0175] Although the application has been described in connection with the embodiments thereof with reference to the various drawings, it will be apparent to those of ordinary skill in the art that variations in the embodiments can be used and that it is not intended to limit the application to the particular form described. From the above discussion and illustrations, one skilled in the art will readily develop variations in the embodiments without departing from the spirit and scope of the application. Accordingly, the application is not limited by the specific examples described herein, but only by the claims that follow, the intent being to cover all modifications and equivalents falling within the spirit and scope of the application. The specification and drawings are, accordingly to be regarded as illustrative rather than restrictive.

[0176] The above description is only specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any changes or replacements within the technical scope disclosed by the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An air conditioning system, characterized by, Comprise: Indoor unit, comprising: indoor heat exchanger and indoor expansion valve; Outdoor unit, comprising compressor; The indoor unit and the outdoor unit are connected by refrigerant gas pipe and refrigerant liquid pipe respectively; First expansion valve, which is arranged on the refrigerant gas pipe between the indoor heat exchanger and the outdoor unit, can be opened when indoor refrigerant leaks to recover the refrigerant of the indoor unit to the outdoor unit, and closed after the refrigerant recovery ends to prevent the refrigerant in the outdoor unit from flowing back to the indoor unit; Second expansion valve, which is arranged on the refrigerant liquid pipe between the outdoor unit and the indoor expansion valve, can be closed when the indoor refrigerant leaks to prevent the refrigerant of the outdoor unit from continuing to flow to the indoor unit, and the refrigerant liquid pipe between the second expansion valve and the indoor expansion valve is closed for storing the refrigerant between the second expansion valve and the indoor expansion valve; The air conditioning system further comprises: Controller configured to: When it is obtained that the refrigerant leaks in the indoor, control the operation mode to switch to the cooling mode, and control the indoor expansion valve and the second expansion valve to be closed and the first expansion valve to be opened; When it is detected that the compressor meets the first preset condition, control the compressor to stop and the first expansion valve to be closed; After controlling the compressor to stop, judge whether the refrigerant continues to leak in the indoor; If yes, start the compressor, and open the first expansion valve and the indoor expansion valve; When it is detected that the compressor meets the first preset condition, control the compressor to stop and the first expansion valve to be closed.

2. The air conditioning system of claim 1, wherein, The air conditioning system further comprises: Refrigerant concentration sensor, electrically connected with the controller, for detecting the refrigerant concentration in the indoor; Before it is obtained that the refrigerant leaks in the indoor, the controller is further configured to: Obtain the refrigerant concentration in the indoor at the current time and the previous time, and if the refrigerant concentration at the current time is greater than that at the previous time, confirm that the refrigerant leaks in the indoor; The judgment of whether the refrigerant continues to leak in the indoor comprises: judging whether the refrigerant concentration at the current time is greater than that at the previous time; and / or, The air conditioning system further comprises: first pressure sensor, which is arranged between the indoor expansion valve and the second expansion valve, for detecting the pressure value at the connecting pipe, which is the refrigerant liquid pipe between the indoor expansion valve and the second expansion valve; The judgment of whether the refrigerant continues to leak in the indoor comprises: Obtain the pressure value at the connecting pipe at the current time and the previous time; Judge whether the pressure value at the connecting pipe at the current time is less than that at the previous time.

3. The air conditioning system of claim 1, wherein, The first preset condition comprises: the running time of the compressor switching to the cooling mode is greater than a preset time.

4. The air conditioning system of claim 1, wherein, The air conditioning system further comprises: Second pressure sensor, for detecting the discharge pressure value of the compressor; the second pressure sensor is electrically connected with the controller; the first preset condition comprises: the discharge pressure value of the compressor is greater than a first preset value; or, The air conditioning system further comprises a temperature sensor configured to detect an exhaust temperature value of the compressor; the temperature sensor is electrically connected to the controller; the first preset condition comprises that the exhaust temperature value of the compressor is greater than a second preset value.

5. The air conditioning system of claim 1, wherein, The air conditioning system further comprises a third pressure sensor configured to detect a suction pressure value of the compressor; The third pressure sensor is electrically connected to the controller; the first preset condition comprises that the suction pressure value of the compressor is less than a third preset value.

6. The air conditioning system of claim 5, wherein, The indoor expansion valve is an indoor electronic expansion valve; The starting of the compressor and the opening of the first expansion valve and the indoor expansion valve further comprise: adjusting the indoor expansion valve to a preset target opening degree according to the suction pressure value of the compressor.

7. The air conditioning system of claim 6, wherein, The air conditioning system further comprises a memory in which a corresponding relationship between the suction pressure value and the preset target opening degree of the indoor expansion valve is stored; The adjusting of the indoor expansion valve to a preset target opening degree according to the suction pressure value of the compressor comprises: The controller acquires the current suction pressure value of the compressor through the third pressure sensor; The controller acquires the preset target opening degree of the indoor expansion valve corresponding to the current suction pressure value from the memory according to the current suction pressure value; The controller controls the indoor expansion valve to adjust to the preset target opening degree.

8. The air conditioning system of claim 1, wherein, The air conditioning system further comprises: an outdoor fan assembly arranged in the outdoor unit and configured to blow air to an outdoor heat exchanger; an indoor fan assembly arranged in the indoor unit and configured to blow air to the indoor heat exchanger; The controller is electrically connected to the outdoor fan assembly and the indoor fan assembly; when the indoor expansion valve and the second expansion valve are both controlled to be closed, the controller is further configured to: control the outdoor fan assembly to be opened, so that the refrigerant in the refrigerant gas pipe recovered between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be opened, so as to improve the efficiency of the refrigerant in the indoor unit from being evaporated from liquid state to gaseous state, and avoid liquid refrigerant from entering the compressor; and / or, when the compressor is controlled to be stopped, the controller is further configured to: control the outdoor fan assembly to be closed, and control the indoor fan assembly to be closed; and / or, when the first expansion valve and the indoor expansion valve are opened, the controller is further configured to: control the outdoor fan assembly to be opened, so that the refrigerant in the refrigerant gas pipe recovered between the compressor and the outdoor heat exchanger flows to the refrigerant liquid pipe between the outdoor heat exchanger and the second expansion valve, and control the indoor fan assembly to be opened, so as to improve the efficiency of the refrigerant in the indoor unit from being evaporated from liquid state to gaseous state, and avoid liquid refrigerant from entering the compressor.

9. The air conditioning system of claim 8, wherein, The control of the indoor fan assembly to be opened comprises that the indoor fan assembly is controlled to run at a first preset gear; and the control of the outdoor fan assembly to be opened comprises that the outdoor fan assembly is controlled to run at a second preset gear. ​

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