Air conditioning system, control method and computer readable storage medium

Abstract

The present disclosure relates to an air conditioning system, a control method and a computer readable storage medium. The air conditioning system comprises an indoor unit, the indoor unit comprises a first heat exchanger and a second heat exchanger, the inlet end of the first heat exchanger is connected to a liquid pipe through a first pipeline, the outlet end of the first heat exchanger is connected to a low-pressure gas pipe, the inlet end of the second heat exchanger is connected to a high-pressure gas pipe, and the outlet end of the second heat exchanger is connected to the first pipeline through a second pipeline, and a first flow control valve is arranged on the second pipeline. The control method comprises the following steps: when the air conditioning system is started in a cooling mode or switched to the cooling mode, the first flow control valve is controlled to be closed to store refrigerant in the second heat exchanger. The first flow control valve is closed, the refrigerant is not circulated and is stored in the second heat exchanger, the refrigerant in the second heat exchanger exchanges heat with the surrounding environment and condenses, and the temperature of the condensed refrigerant is close to the indoor temperature, so that the temperature of the cold air passing through the second heat exchanger is not affected, and the user's cooling comfort experience is improved.

Description

Technical Field

[0001] This disclosure relates to the field of air conditioning technology, and more particularly to an air conditioning system, control method, and computer-readable storage medium. Background Technology

[0002] In some related technologies, for three-pipe indoor units, in dehumidification mode, the main heat exchanger acts as an evaporator for dehumidification and cooling, while the auxiliary heat exchanger acts as a condenser for heating the air, achieving dehumidification without cooling. However, in cooling mode, because the indoor unit's return air first passes through the main heat exchanger and then the outlet air through the auxiliary heat exchanger, and the auxiliary heat exchanger is located on the high-pressure side with circulating refrigerant, the air cooled by the main heat exchanger is reheated by the auxiliary heat exchanger when it passes through it, causing the actual outlet air temperature to rise by 3°C to 5°C. Summary of the Invention

[0003] Some embodiments of this disclosure provide an air conditioning system, control method, and computer-readable storage medium for mitigating the problem of excessively high outlet air temperature in cooling mode.

[0004] In one aspect of this disclosure, a control method for an air conditioning system is provided, wherein the air conditioning system includes an indoor unit, the indoor unit includes a first heat exchanger and a second heat exchanger, the inlet end of the first heat exchanger is connected to a liquid pipe via a first pipeline, the outlet end of the first heat exchanger is connected to a low-pressure gas pipe, the inlet end of the second heat exchanger is connected to a high-pressure gas pipe, and the outlet end of the second heat exchanger is connected to the first pipeline via a second pipeline, the second pipeline being provided with a first flow control valve; the control method includes the following steps:

[0005] When the air conditioning system is turned on in cooling mode or switched to cooling mode, the first flow control valve is closed so that refrigerant is stored in the second heat exchanger.

[0006] In some embodiments, the control method for the air conditioning system further includes the following steps: controlling the first flow control valve to open at regular intervals or at irregular intervals, so that when the first flow control valve is opened, the second heat exchanger releases the refrigerant stored therein.

[0007] In some embodiments, the control method for an air conditioning system further includes the following step: controlling the first flow control valve to a first preset opening degree. Turn on, and the first preset time is reached after the turn-on time. Then it is shut off so that the second heat exchanger releases refrigerant and then stores refrigerant.

[0008] In some embodiments, a second flow control valve is provided on the first pipeline, and controlling the opening of the first flow control valve at irregular intervals includes: determining whether to open the first flow control valve based on the superheat of the first heat exchanger and the opening degree of the second flow control valve.

[0009] In some embodiments, determining whether to open the first flow control valve based on the superheat of the first heat exchanger and the opening degree of the second flow control valve includes:

[0010] The superheat of the first heat exchanger is greater than or equal to the first preset temperature. ;and,

[0011] The opening degree of the second flow control valve is greater than or equal to the second preset opening degree. ;

[0012] Control the first flow control valve to open.

[0013] In some embodiments, controlling the opening of the first flow control valve intermittently further includes:

[0014] Second preset time The system continuously detects and opens the first flow control valve after continuously meeting the opening conditions of the first flow control valve.

[0015] In some embodiments, controlling the opening of the first flow control valve intermittently further includes:

[0016] Based on the superheat of the first heat exchanger, the opening degree of the second flow control valve, the temperature difference between the outlet and inlet of the second heat exchanger, determine whether to close the first flow control valve.

[0017] In some embodiments, determining whether to close the first flow control valve based on the superheat of the first heat exchanger, the opening degree of the second flow control valve, and the outlet and inlet temperatures of the second heat exchanger includes:

[0018] The superheat of the first heat exchanger is less than or equal to the second preset temperature. Furthermore, the opening degree of the second flow control valve is ≤ the third preset opening degree. ;as well as

[0019] After the first flow control valve is opened, the temperature difference at the outlet of the second heat exchanger is greater than or equal to the third preset temperature. And the temperature difference at the inlet of the second heat exchanger is ≥ the fourth preset temperature. ;

[0020] Control the first flow control valve to close.

[0021] In some embodiments, controlling the timing of opening the first flow control valve includes:

[0022] When there is at least one indoor unit and all of the indoor units are turned on, the third preset time is reached after the start-up time. Then, the first flow control valve is opened.

[0023] In some embodiments, controlling the opening of the first flow control valve at regular intervals further includes:

[0024] When there are at least two indoor units, and not all of them are turned on, the operation continues for a third preset time. back,

[0025] The first flow control valve of the indoor unit, which controls the start-up, opens to a first preset degree. Turn on;

[0026] The first flow control valve of the indoor unit that is not turned on is opened to its maximum degree. Start.

[0027] In some embodiments, controlling the opening of the first flow control valve at regular intervals further includes:

[0028] The first flow control valve of the indoor unit, which controls the start-up, is at a first preset opening degree. Start-up time reaches the first preset time Close later;

[0029] The first flow control valve of the indoor unit that is not turned on is kept at its maximum opening. Start.

[0030] In some embodiments, the air conditioning system includes an outdoor unit, the outdoor unit including a compressor and a condenser; characterized in that, controlling the opening of the first flow control valve intermittently includes:

[0031] Based on the saturation temperature corresponding to the compressor's outlet pressure and the condenser's outlet temperature, determine whether to open the first flow control valve.

[0032] In some embodiments, determining whether to open the first flow control valve based on the saturation temperature corresponding to the compressor outlet pressure and the condenser outlet temperature includes:

[0033] When the compressor starts running for the fourth preset time... Then, at the fifth preset time Continuous internal monitoring is performed until the saturation temperature corresponding to the compressor's outlet pressure reaches the fifth preset time. The difference within ≥ the fifth preset temperature ;and

[0034] The difference between the saturation temperature corresponding to the compressor outlet pressure and the condenser outlet temperature is ≤ the sixth preset temperature. ,

[0035] Control the first flow control valve to open.

[0036] In some embodiments, controlling the opening of the first flow control valve intermittently further includes:

[0037] Based on the saturation temperature corresponding to the compressor's outlet pressure, the condenser's outlet temperature, and the temperature difference between the outlet and inlet ends of the second heat exchanger, determine whether to close the first flow control valve.

[0038] In some embodiments, determining whether to close the first flow control valve based on the saturation temperature corresponding to the compressor outlet pressure, the condenser outlet temperature, and the temperature difference between the outlet and inlet ends of the second heat exchanger includes:

[0039] After the first flow control valve opens, it will close when one of the following three conditions is met:

[0040] The difference between the compressor's outlet pressure and the saturation temperature is greater than or equal to the seventh preset temperature. Furthermore, the difference between the saturation temperature corresponding to the compressor outlet pressure and the condenser outlet temperature is ≥ the eighth preset temperature. ;

[0041] The temperature difference at the outlet of the second heat exchanger is ≥ the ninth preset temperature. And the temperature difference at the inlet of the second heat exchanger is ≥ the tenth preset temperature. ;

[0042] The first flow control valve opens to a first preset degree. It is turned on, and the turn-on time reaches the first preset time. .

[0043] In another aspect of this disclosure, an air conditioning system is also provided, including an indoor unit and a controller. The indoor unit includes a first heat exchanger and a second heat exchanger. The inlet end of the first heat exchanger is connected to a liquid pipe via a first pipeline, and the outlet end of the first heat exchanger is connected to a low-pressure gas pipe. The inlet end of the second heat exchanger is connected to a high-pressure gas pipe, and the outlet end of the second heat exchanger is connected to the first pipeline via a second pipeline. A first flow control valve is provided on the second pipeline. The controller is electrically connected to the first flow control valve, and the controller is configured to implement the control method of the air conditioning system described above.

[0044] In another aspect of this disclosure, a computer-readable storage medium is also provided, on which a computer program is stored, wherein the program, when executed by a processor, implements the control method described above.

[0045] Based on the above technical solution, this disclosure has at least the following beneficial effects:

[0046] In some embodiments, when the air conditioning system is turned on in cooling mode or switched to cooling mode, the first flow control valve is closed, the refrigerant does not circulate and is stored in the second heat exchanger. The refrigerant in the second heat exchanger exchanges heat with the surrounding environment and condenses. The temperature of the condensed refrigerant is close to the indoor temperature. Therefore, the temperature of the cold air passing through the second heat exchanger will not be affected, which alleviates the problem of high outlet air temperature and improves the user's cooling comfort experience. Attached Figure Description

[0047] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this disclosure, illustrate exemplary embodiments of the present disclosure and are used to explain the disclosure, but do not constitute an undue limitation of the disclosure. In the drawings:

[0048] Figure 1 This is a schematic diagram of an air conditioning system provided according to some embodiments of the present disclosure;

[0049] Figure 2 This is a schematic diagram of a three-pipe internal machine provided according to some embodiments of the present disclosure;

[0050] Figure 3 This is a flowchart illustrating a first control method for an air conditioning system provided according to some embodiments of the present disclosure;

[0051] Figure 4 This is a flowchart illustrating a second control method for an air conditioning system provided according to some embodiments of the present disclosure;

[0052] Figure 5 This is a flowchart illustrating a third control method for an air conditioning system provided according to some embodiments of the present disclosure.

[0053] The labels in the attached diagram are explained as follows:

[0054] 1-First heat exchanger; 2-Second heat exchanger; 3-Liquid pipe; 4-Low-pressure gas pipe; 5-High-pressure gas pipe; 6-First pipeline; 7-Second pipeline; 8-Second flow control valve; 9-First flow control valve; 10-Compressor; 11-Condenser; 12-First detection element; 13-Second detection element; 14-Third detection element; 15-Fourth detection element; 16-Third heat exchanger; 17-Subcooler; 18-Gas-liquid separator; 19-Four-way valve;

[0055] 100 - Indoor unit; 200 - Outdoor unit; 300 - Controller.

[0056] It should be understood that the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Furthermore, the same or similar reference numerals denote the same or similar components. Detailed Implementation

[0057] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the present disclosure or its application or use. The present disclosure may be implemented in many different forms and is not limited to the embodiments herein. These embodiments are provided so that the present disclosure will be thorough and complete, and will fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless specifically stated otherwise, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0058] The terms "first," "second," and similar words used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "contains" mean that the element preceding the word encompasses the element listed after it, and do not exclude the possibility of encompassing other elements as well. Terms such as "above," "below," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, this relative positional relationship may also change accordingly.

[0059] In this disclosure, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.

[0060] All terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0061] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0062] Figure 1 This is a structural schematic diagram of some embodiments of the air conditioning system according to this disclosure. (Reference) Figure 1 In some embodiments, the air conditioning system includes an indoor unit 100 and an outdoor unit 200.

[0063] In some embodiments, the indoor unit 100 includes a three-pipe indoor unit.

[0064] In some embodiments, the indoor unit 100 includes a two-pipe indoor unit.

[0065] refer to Figure 2 In some embodiments, the three-pipe indoor unit includes a first heat exchanger 1 and a second heat exchanger 2. The inlet end of the first heat exchanger 1 is connected to the liquid pipe 3 through a first pipe 6, and the outlet end of the first heat exchanger 1 is connected to the low-pressure gas pipe 4. The inlet end of the second heat exchanger 2 is connected to the high-pressure gas pipe 5, and the outlet end of the second heat exchanger 2 is connected to the first pipe 6 through a second pipe 7. A first flow control valve 9 is provided on the second pipe 7.

[0066] The first heat exchanger 1 is the main heat exchanger. The second heat exchanger 2 is the auxiliary heat exchanger.

[0067] The control method for an air conditioning system includes the following steps:

[0068] When the air conditioning system is turned on in cooling mode or switched to cooling mode, the first flow control valve 9 is closed so that refrigerant is stored in the second heat exchanger 2.

[0069] In the above embodiment, the first flow control valve 9 is closed, and the refrigerant does not circulate but is stored in the second heat exchanger 2. The high-temperature gaseous refrigerant in the second heat exchanger 2 exchanges heat with the surrounding environment and gradually cools down, condensing into a liquid state. The liquid refrigerant is stored in the second heat exchanger 2. Since the temperature of the condensed refrigerant is basically close to the indoor temperature, the outlet temperature of the cold air passing through the second heat exchanger 2 will not be affected, alleviating the problem of high outlet temperature and improving the user's cooling comfort experience.

[0070] In some embodiments, the first flow control valve 9 includes an expansion valve or a switching valve.

[0071] In some embodiments, the control method of the air conditioning system further includes the following steps: controlling the first flow control valve 9 to open at regular intervals or at irregular intervals, so that when the first flow control valve 9 is opened, the second heat exchanger 2 releases the refrigerant stored therein.

[0072] refer to Figure 2In cooling mode, the high-temperature gaseous refrigerant in the high-pressure pipe 5 flows into the second heat exchanger 2, and then from the second heat exchanger 2 to the second pipe 7. A first flow control valve 9 is installed on the second pipe 7. If the first flow control valve 9 is kept open, high-temperature gaseous refrigerant will flow through the second heat exchanger 2, causing the cold air flowing through it to exchange heat with the high-temperature gaseous refrigerant, resulting in a high outlet air temperature. However, if the first flow control valve 9 is closed, the refrigerant stops flowing and is stored in the second heat exchanger 2 and the high-pressure pipe 5. The high-temperature gaseous refrigerant in the second heat exchanger 2 and the high-pressure pipe 5 will gradually cool down, condense into a liquid state through heat exchange with the ambient temperature, and be stored in the second heat exchanger 2 and the high-pressure pipe 5. Since the temperature of the condensed refrigerant is close to the room temperature, the outlet air temperature of the cold air passing through the second heat exchanger 2 will not be affected, ensuring the user's cooling comfort experience. However, as the pipeline becomes longer, more refrigerant is stored in the high-pressure gas pipe 5, while less refrigerant circulates in the system, which will affect the operation of the system. Therefore, the first flow control valve 9 cannot be closed indefinitely.

[0073] Based on this, the air conditioning system control method provided in this embodiment controls the opening of the first flow control valve 9 at regular intervals or irregular intervals, so that the second heat exchanger 2 and the high-pressure gas pipe 5 act as a liquid storage tank. When the first flow control valve 9 is open, it can release refrigerant; when the first flow control valve 9 is closed, the second heat exchanger 2 and the high-pressure gas pipe 5 can store refrigerant. Therefore, refrigerant is continuously stored, forming a dynamic balance. This can alleviate the problem of excessively high outlet air temperature in cooling mode, making the outlet air temperature of the three-pipe indoor unit the same as that of a normal indoor unit in cooling mode, thus improving the user's cooling experience, without causing a refrigerant shortage in the system and affecting system operation.

[0074] In some embodiments, the control method for an air conditioning system further includes the following steps:

[0075] Control the first flow control valve 9 to a first preset opening degree Turn on, and the first preset time is reached after the turn-on time. Then it is closed so that the second heat exchanger 2 releases refrigerant and then stores refrigerant.

[0076] To effectively control the release of liquid refrigerant in the second heat exchanger 2 and the high-pressure gas pipe 5, the refrigerant can be released within a preset time period, such as 10 minutes or 15 minutes. To make the refrigerant release within this preset time period, it is necessary to find a suitable opening degree for the first flow control valve 9.

[0077] If refrigerant is stored in the high-pressure gas pipe 5 and the second heat exchanger 2, and the first flow control valve 9 is opened for a short period of time (e.g., 10 minutes), and the indoor unit outlet air temperature does not change, the opening degree of the first flow control valve 9 is the first preset opening degree. This causes the first flow control valve 9 to open to the first preset degree. Start, at the first preset time The refrigerant in the second heat exchanger 2 and the high-pressure gas pipe 5 is released, which not only allows the liquid refrigerant in the second heat exchanger 2 and the high-pressure gas pipe 5 to be released, but also prevents the system from running out of refrigerant and does not cause changes in the outlet air temperature. Then the first flow control valve 9 is closed, and the refrigerant continues to be stored in the second heat exchanger 2 and the high-pressure gas pipe 5.

[0078] First preset time and the first preset opening The value can be obtained from multiple sets of experimental data, for example, by setting a first preset opening degree. Afterwards, the high-temperature gaseous refrigerant drives the refrigerant flow in the high-pressure pipe 5 and the second heat exchanger 2. If, exactly at the 10th minute, the second heat exchanger 2 can maintain the same outlet air temperature, then the refrigerant in the second heat exchanger 2 is the refrigerant previously stored in the high-pressure pipe 5, which is close to the room temperature. At the 11th minute, the second heat exchanger 2 causes a change in the outlet air temperature. At this time, the refrigerant in the second heat exchanger 2 is the high-temperature gaseous refrigerant introduced through the high-pressure pipe 5, and the previously stored refrigerant close to the room temperature has been released. This completes the first preset time. Set to 10 minutes, at the first preset time. Inside, the second heat exchanger 2 will not cause a change in the outlet air temperature. At this time, closing the first flow control valve 9 prevents high-temperature gaseous refrigerant from entering the second heat exchanger 2. The refrigerant inside the second heat exchanger 2 is the condensed refrigerant previously stored in the high-pressure gas pipe 5 (temperature close to the room temperature). The second heat exchanger 2 still will not cause a change in the outlet air temperature. Therefore, it can alleviate the problem of excessively high outlet air temperature in cooling mode, improving the user's cooling experience, without causing refrigerant shortages and affecting system operation. If the first preset time is not fixed... Simply controlling the opening of the first flow control valve 9 by detecting changes in the indoor unit pipe temperature makes it difficult to find a suitable opening for the first flow control valve 9, and it is also impossible to know whether the outlet air temperature has changed.

[0079] In some embodiments, the first preset time The value range is 10min~15min, optionally, the first preset time. It takes 10 minutes.

[0080] In some embodiments, controlling the opening of the first flow control valve 9 intermittently includes:

[0081] Based on the superheat of the first heat exchanger 1 and the opening degree of the second flow control valve 8, determine whether to open the first flow control valve 9.

[0082] When the first flow control valve 9 is closed, a large amount of liquid refrigerant will be stored in the second heat exchanger 2 and the high-pressure gas pipe 5. At this time, the system will experience a refrigerant shortage. During this shortage, the superheat of the first heat exchanger 1 will increase, and as the amount of refrigerant circulating in the system decreases, the opening of the second flow control valve 8 will increase (the second flow control valve 8 can continuously adjust its opening based on the temperature). This serves as the criterion for determining whether the first flow control valve 9 is open, allowing for a relatively accurate assessment of when it will open. In cases with multiple three-pipe indoor units, each unit needs to be tested individually. If a single indoor unit malfunctions, that unit will stop operating without affecting the other indoor units in the system.

[0083] In some embodiments, determining whether to open the first flow control valve 9 based on the superheat of the first heat exchanger 1 and the opening degree of the second flow control valve 8 includes:

[0084] The superheat of the first heat exchanger 1 is greater than or equal to the first preset temperature. ;and,

[0085] The opening degree of the second flow control valve 8 is greater than or equal to the second preset opening degree. ;

[0086] Control the first flow control valve 9 to open.

[0087] Under the above conditions, it can be determined relatively accurately that the system is short of refrigerant, at which point the first flow control valve 9 is opened.

[0088] In some embodiments, the first preset temperature The value range is 4℃~6℃, and optionally, the first preset temperature The temperature is 5℃.

[0089] In some embodiments, the second preset opening degree The value range is 0.55. ~0.65 Optionally, a second preset opening degree. It is 0.6 .in, This is the maximum opening degree of the second flow control valve 8.

[0090] In some embodiments, controlling the opening of the first flow control valve 9 intermittently further includes:

[0091] Second preset time The system continuously detects and opens the first flow control valve 9 after the opening conditions of the first flow control valve 9 are continuously met.

[0092] Second preset time Continuous internal monitoring is used to mitigate misjudgments caused by system fluctuations.

[0093] In some embodiments, the second preset time The value range is 8 min to 12 min. Optionally, a second preset time... It takes 10 minutes.

[0094] In some embodiments, a second flow control valve 8 is provided on the first pipeline 6 to control the opening of the first flow control valve 9 intermittently, and further includes:

[0095] Based on the superheat of the first heat exchanger 1, the opening degree of the second flow control valve 8, and the temperature difference between the outlet and inlet of the second heat exchanger 2, determine whether to close the first flow control valve 9.

[0096] After the first flow control valve 9 is opened, the closing conditions of the first flow control valve 9 are determined. Since the first flow control valve 9 is opened, the refrigerant will re-enter the system for circulation, so the superheat of the first heat exchanger 1 and the opening degree of the second flow control valve 8 will return to normal.

[0097] When the first flow control valve 9 is closed, the temperatures of the outlet and inlet pipes (inlet and outlet ends) of the second heat exchanger 2 are basically the same as the ambient temperature after the refrigerant condenses. When the first flow control valve 9 is opened, the high-pressure gas refrigerant pushes the liquid refrigerant forward, and the liquid refrigerant re-enters the system from the high-pressure gas side. The temperatures of the outlet and inlet pipes of the second heat exchanger 2 gradually rise. The change in the outlet and inlet temperatures of the second heat exchanger 2 is used to determine the state of the refrigerant in the second heat exchanger 2. When the temperature rises faster, it indicates that most of the liquid refrigerant has been released. This is used to determine whether the refrigerant in the second heat exchanger 2 has been released. At the critical moment when the refrigerant in the second heat exchanger 2 will not affect the outlet air temperature, the first flow control valve 9 is closed.

[0098] The superheat of the first heat exchanger 1 is equal to the difference between the outlet temperature and the inlet temperature of the first heat exchanger 1. The superheat of the first heat exchanger 1 is taken as a positive value.

[0099] The temperature difference between the outlet and inlet of the second heat exchanger 2 refers to the following: starting from the start of control, the initial temperatures at the outlet and inlet of the second heat exchanger 2 are recorded respectively. Then, the temperature is continuously monitored in real time to obtain the real-time temperature at the outlet and the real-time temperature at the inlet of the second heat exchanger 2. The difference between the real-time temperature at the outlet and the initial temperature of the second heat exchanger 2 is the temperature difference between the outlet and the initial temperature of the second heat exchanger 2. The difference between the real-time temperature at the inlet and the initial temperature of the second heat exchanger 2 is the temperature difference between the inlet and the initial temperature of the second heat exchanger 2.

[0100] The control system also includes a first detection element 12 and a second detection element 13. The first detection element 12 is located at the inlet end of the first heat exchanger 1, and the second detection element 13 is located at the outlet end of the first heat exchanger 1. Optionally, the first detection element 12 is located in the first pipeline 6, and the second detection element 13 is located in the low-pressure gas pipeline 4.

[0101] In some embodiments, the air conditioning system further includes a third detection element 14 and a fourth detection element 15. The third detection element 14 is disposed at the inlet end of the second heat exchanger 2 and is used to detect the inlet end temperature of the second heat exchanger 2. The fourth detection element 15 is disposed at the outlet end of the second heat exchanger 2 and is used to detect the outlet end temperature of the second heat exchanger 2. Optionally, the third detection element 14 is disposed in the high-pressure gas pipe 5 and the fourth detection element 15 is disposed in the second pipeline 7.

[0102] Optionally, the first detection element 12, the second detection element 13, the third detection element 14 and the fourth detection element 15 may each include a temperature sensing bulb or a temperature sensor.

[0103] In some embodiments, determining whether to close the first flow control valve 9 based on the superheat of the first heat exchanger 1, the opening degree of the second flow control valve 8, and the outlet and inlet temperatures of the second heat exchanger 2 includes:

[0104] The superheat of the first heat exchanger 1 is less than or equal to the second preset temperature. Furthermore, the opening degree of the second flow control valve 8 is ≤ the third preset opening degree. ;as well as

[0105] After the first flow control valve 9 is opened, the temperature difference at the outlet of the second heat exchanger 2 is greater than or equal to the third preset temperature. And the temperature difference at the inlet of the second heat exchanger 2 is ≥ the fourth preset temperature. ;

[0106] Control the first flow control valve 9 to close.

[0107] If the above conditions are met, it means that the refrigerant in the second heat exchanger 2 and the high-pressure gas pipe 5 has entered the system, the superheat of the first heat exchanger 1 has returned to normal, the opening of the second flow control valve 8 has returned to normal, and the refrigerant in the second heat exchanger 2 will not affect the outlet air temperature. Therefore, the first flow control valve 9 is closed to prevent the high-pressure gaseous refrigerant entering the second heat exchanger 2 from affecting the outlet air temperature.

[0108] In some embodiments, the second preset temperature The value range is 1℃ to 3℃. Optionally, the second preset temperature... It is 2℃.

[0109] In some embodiments, the third preset opening degree The value range is 0.35. ~0.45 Optionally, a third preset opening. It is 0.4 .

[0110] In some embodiments, the third preset temperature The value range is 8℃~10℃. Optionally, a third preset temperature... The temperature is 10℃.

[0111] In some embodiments, the fourth preset temperature The value range is 6℃ to 8℃. Optionally, a fourth preset temperature... The temperature is 6℃.

[0112] In some embodiments, determining whether to close the first flow control valve 9 based on the superheat of the first heat exchanger 1, the opening degree of the second flow control valve 8, and the outlet and inlet temperatures of the second heat exchanger 2 includes:

[0113] Control the first flow control valve 9 to a first preset opening degree Turn on, and the first preset time is reached after the turn-on time. Then it is closed so that the second heat exchanger 2 releases refrigerant and then stores refrigerant.

[0114] In some short-pipe systems or when the number of connected three-pipe indoor units is small, the liquid refrigerant stored on the second heat exchanger 2 side is less due to the short pipes. In this case, the first flow control valve 9 can be opened periodically to release the refrigerant from the second heat exchanger 2.

[0115] In some embodiments, controlling the opening of the first flow control valve 9 at regular intervals includes:

[0116] When there is at least one indoor unit 100 and all indoor units 100 are turned on, the third preset time is reached when the turn-on time is reached. Then, the first flow control valve 9 is opened.

[0117] If there is only one three-pipe indoor unit in the entire system and it is powered on, or if there are multiple three-pipe indoor units in the entire system and they are all powered on, then the system will activate at the third preset time after the power-on time. Then, the first flow control valve 9 is opened, and the first flow control valve 9 is opened at regular intervals to release the refrigerant from the second heat exchanger 2.

[0118] Based on testing or experience, when all indoor units are 100% powered on, the startup time reaches the third preset time. There may be a refrigerant shortage in the system. Therefore, the first flow control valve 9 is opened to release the refrigerant in the second heat exchanger 2 to alleviate the problem of refrigerant shortage affecting system operation.

[0119] The operation of indoor unit 100 is set by the user. When the user needs to use the air conditioner, they control indoor unit 100 to turn on; conversely, when the user does not need to use the air conditioner, they control indoor unit 100 to turn off.

[0120] The air conditioning system includes at least one indoor unit 100. The user can set the indoor unit 100 to be turned on or off. The user can set one indoor unit 100 to be turned on or two or more indoor units 100 to be turned on.

[0121] Indoor unit 100 includes three-pipe indoor units and two-pipe indoor units, etc.

[0122] When the indoor unit 100 is turned on in cooling mode or switched to cooling mode, the first flow control valve 9 of the three-pipe indoor unit is in the closed state. At this time, the three-pipe indoor unit is equivalent to a two-pipe indoor unit.

[0123] In some embodiments, the third preset time The value range is 0.5 h to 1 h (hours). Optionally, a third preset time... It takes 1 hour.

[0124] In some embodiments, controlling the opening of the first flow control valve 9 at regular intervals further includes:

[0125] When there are at least two indoor units 100, and not all indoor units 100 are turned on, the third preset time is reached when the turn-on time is reached. back,

[0126] The first flow control valve 9 of the indoor unit 100, which controls the start-up, is at a first preset opening degree. Turn on;

[0127] The first flow control valve 9 of the indoor unit 100 that is not turned on is opened to its maximum degree. Start.

[0128] When there are at least two three-pipe indoor units, it is necessary to distinguish whether more than one three-pipe indoor unit is not turned on when the indoor unit is turned on. If so, the first flow control valve 9 of the unturned unit can be fully opened to allow refrigerant to flow, prevent the system from lacking refrigerant and affecting the system operation. Since the second expansion valve of the user's three-pipe indoor unit is not in use, it will not affect the user.

[0129] In some embodiments, controlling the opening of the first flow control valve 9 at regular intervals further includes:

[0130] The first flow control valve 9 of the indoor unit 100, which controls the start-up, is at a first preset opening degree. Start-up time reaches the first preset time Close later;

[0131] The first flow control valve 9 of the indoor unit 100 that is not turned on maintains its maximum opening. Start.

[0132] The first flow control valve 9 of the indoor unit 100 that is not turned on maintains its maximum opening. Since the system is not in use, it will not affect the user and can alleviate the problem of insufficient refrigerant in the system.

[0133] In some embodiments, the air conditioning system further includes an outdoor unit 200, which includes a compressor 10 and a condenser 11.

[0134] Controlling the opening of the first flow control valve 9 at irregular intervals includes:

[0135] Based on the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11, determine whether to open the first flow control valve 9.

[0136] When the first flow control valve 9 is closed, the refrigerant is stored in the high-pressure gas pipe 5 and the second heat exchanger 2, that is, stored on the high-pressure gas side. During normal cooling operation, due to the lack of refrigerant, the high pressure difference and subcooling of the outdoor unit 200 will decrease. Using this as a judgment condition, it is possible to determine whether to open the first flow control valve 9, and the timing of opening the first flow control valve 9 can be determined more accurately.

[0137] The high pressure difference of outdoor unit 200 is the saturation temperature difference corresponding to the outlet pressure of compressor 10.

[0138] The subcooling of the outdoor unit can be obtained by calculating the difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11. In other words, the subcooling of the outdoor unit is equal to the difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11.

[0139] In some embodiments, determining whether to open the first flow control valve 9 based on the saturation temperature corresponding to the outlet pressure of the compressor 10 and the outlet temperature of the condenser 11 includes:

[0140] When the compressor 10 starts running for the fourth preset time... Then, at the fifth preset time Continuous internal monitoring is performed, and the saturation temperature corresponding to the outlet pressure of compressor 10 is monitored for a fifth preset time. The difference within ≥ the fifth preset temperature ;and

[0141] The difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11 is ≤ the sixth preset temperature. ,

[0142] Control the first flow control valve 9 to open.

[0143] The difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11 is the subcooling of the outdoor unit. Because the first flow control valve 9 is closed in cooling mode, the refrigerant is stored in the high-pressure gas pipe 5 and the second heat exchanger 2, i.e., stored on the high-pressure gas side. During normal cooling operation, due to refrigerant shortage, the high pressure differential and subcooling of the outdoor unit 200 will decrease. Using this as a criterion, the timing for opening the first flow control valve 9 can be determined relatively accurately.

[0144] In some embodiments, the fourth preset time The value range is 1h to 2h. Optionally, the fourth preset time... It takes 1 hour.

[0145] In some embodiments, the fifth preset time The value range is 10 min to 15 min. Optionally, the fifth preset time... It takes 15 minutes.

[0146] In some embodiments, the fifth preset temperature The value range is 2℃~3℃. Optionally, the fifth preset temperature... It is 2℃.

[0147] In some embodiments, the sixth preset temperature The value range is 5℃ to 7℃. Optionally, the sixth preset temperature... The temperature is 6℃.

[0148] In some embodiments, controlling the opening of the first flow control valve 9 intermittently further includes:

[0149] Based on the saturation temperature corresponding to the outlet pressure of compressor 10, the outlet temperature of condenser 11, the temperature difference between the outlet end of the second heat exchanger 2 and the temperature difference between the inlet end of the second heat exchanger 2, determine whether to close the first flow control valve 9.

[0150] When the first flow control valve 9 opens, the high-pressure gas refrigerant pushes the liquid refrigerant forward, causing the liquid refrigerant to re-enter the system from the high-pressure gas side. The inlet and outlet pipe temperatures of the second heat exchanger 2 gradually rise. The state of the refrigerant within the second heat exchanger 2 is determined by the changes in its outlet and inlet temperatures. A faster temperature rise indicates that most of the liquid refrigerant has been released, thus determining whether the refrigerant within the second heat exchanger 2 has been released. The first flow control valve 9 is closed at the critical moment when the refrigerant in the second heat exchanger 2 will not affect the outlet air temperature. Furthermore, after the refrigerant in the second heat exchanger 2 is released, the high pressure differential and subcooling of the outdoor unit 200 will increase. This is used as a criterion to determine whether to close the first flow control valve 9. Therefore, using the changes in the outdoor unit's subcooling and the temperature difference between the outlet and inlet of the second heat exchanger 2 as conditions for determining whether to close the first flow control valve 9 yields relatively accurate results.

[0151] In some embodiments, determining whether to close the first flow control valve 9 based on the saturation temperature corresponding to the outlet pressure of the compressor 10, the outlet temperature of the condenser 11, the temperature difference between the outlet end of the second heat exchanger 2 and the temperature difference between the inlet end of the second heat exchanger 2, includes:

[0152] After the first flow control valve 9 is opened, it will close when one of the following three conditions is met:

[0153] 1) The difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11 is greater than or equal to the seventh preset temperature. Furthermore, the saturation temperature difference corresponding to the outlet pressure of compressor 10 is ≥ the eighth preset temperature. ;

[0154] 2) The temperature difference at the outlet of the second heat exchanger 2 is greater than or equal to the ninth preset temperature. And the temperature difference at the inlet of the second heat exchanger 2 is ≥ the tenth preset temperature. ;

[0155] 3) The first flow control valve 9 is at the first preset opening degree It is turned on, and the turn-on time reaches the first preset time. .

[0156] When the first flow control valve 9 opens, the high-pressure gas refrigerant pushes the liquid refrigerant forward, causing the liquid refrigerant to re-enter the system from the high-pressure gas side. The inlet and outlet pipe temperatures of the second heat exchanger 2 gradually rise. The state of the refrigerant within the second heat exchanger 2 is determined by the changes in its outlet and inlet temperatures. A faster temperature rise indicates that most of the liquid refrigerant has been released, thus determining whether the refrigerant within the second heat exchanger 2 has been released. The first flow control valve 9 is closed at the critical moment when the refrigerant in the second heat exchanger 2 will not affect the outlet air temperature. Furthermore, after the refrigerant in the second heat exchanger 2 is released, the high pressure differential and subcooling of the outdoor unit 200 will increase. This is used as a criterion to determine whether to close the first flow control valve 9. Therefore, using the changes in the outdoor unit's subcooling and the temperature difference between the outlet and inlet of the second heat exchanger 2 as conditions for determining whether to close the first flow control valve 9 yields relatively accurate results.

[0157] In some embodiments, the seventh preset temperature The value range is 8℃~10℃. Optionally, the seventh preset temperature... The temperature is 10℃.

[0158] In some embodiments, the eighth preset temperature The value range is 1℃~2℃. Optionally, the eighth preset temperature... It is 2℃.

[0159] In some embodiments, the ninth preset temperature The value range is 8℃~10℃. Optionally, the ninth preset temperature... The temperature is 10℃.

[0160] In some embodiments, the tenth preset temperature The value range is 6℃ to 8℃. Optionally, the tenth preset temperature... The temperature is 6℃.

[0161] The air conditioning system control method disclosed herein includes at least three control schemes. In cooling mode, the air conditioning system can combine and use these schemes according to actual conditions. The following is a description of the appendix. Figures 3 to 5 The three control schemes are described in detail.

[0162] Control scheme 1: Use the indoor unit's superheat as the judgment criterion.

[0163] The control is based on the superheat of the first heat exchanger 1 in the indoor unit and the opening of the second flow control valve 8. The state of the refrigerant in the high-pressure gas pipe 5 and the second heat exchanger 2 is determined by the temperature changes at the outlet and inlet of the second heat exchanger 2.

[0164] Control principle: In the initial start-up cooling mode, the first flow control valve 9 is closed and the second flow control valve 8 is open, and the second flow control valve 8 can automatically adjust its opening degree according to the pipe temperature.

[0165] When the first flow control valve 9 is closed, a large amount of refrigerant will be stored in the second heat exchanger 2 and the high-pressure gas pipe 5. At this time, the system will experience a refrigerant shortage. During this shortage, the superheat of the first heat exchanger 1 will increase, and as the amount of refrigerant circulating in the system decreases, the opening of the second flow control valve 8 will increase (the second flow control valve 8 continuously adjusts its opening based on the temperature). Using this as an entry condition, the timing for opening the first flow control valve 9 can be determined relatively accurately. Each indoor unit is tested individually. If a single indoor unit malfunctions, that unit will stop operating without affecting the other indoor units in the system.

[0166] After determining that the entry conditions are met, the action is executed, and the first flow control valve 9 opens to the first preset opening degree. .

[0167] After the execution action is initiated, the exit conditions are determined. Since the first flow control valve 9 is open, the refrigerant will re-enter the system for circulation, so the superheat of the first heat exchanger 1 of the indoor unit and the opening degree of the second flow control valve 8 will return to normal.

[0168] When the first flow control valve 9 is closed, the inlet and outlet pipe temperatures of the second heat exchanger 2 are basically the same as the ambient temperature after the refrigerant condenses. When the first flow control valve 9 is opened, the liquid refrigerant re-enters the system from the high-pressure gas side, and the inlet and outlet pipe temperatures of the second heat exchanger 2 gradually rise. The change in inlet and outlet pipe temperatures, that is, the change in temperature at the inlet end and the change in temperature at the outlet end of the second heat exchanger 2, are used to determine the state of the refrigerant in the second heat exchanger 2.

[0169] 1. Entry conditions: Continuous detection for 10 minutes (second preset time) Second preset time The value range is 8min ~ 12min, with 10min being preferred. If conditions ① and ② are met simultaneously (meeting conditions ① and ② indicates that the system is short of refrigerant), then the action will be executed. Each indoor unit will individually check the entry conditions and the action to be executed.

[0170] ① Indoor unit superheat (outlet temperature of first heat exchanger 1 - inlet temperature of first heat exchanger 1) ≥ 5℃ (first preset temperature) First preset temperature The value range is 4℃~6℃, and optionally, the first preset temperature The temperature is 5℃.

[0171] ② The opening degree of the second flow control valve 8 is ≥0.6. (Second preset opening) Second preset opening degree The value range is 0.55. ~0.65 Optionally, a second preset opening degree. It is 0.6 .in, This is the maximum opening degree of the second flow control valve 8.

[0172] 2. Action: The first flow control valve 9 opens to the first preset opening degree. .

[0173] 3. Exit Conditions: Exit conditions ① and ② are met simultaneously, or condition ③ is met alone, and the entry conditions of entry control scheme one above are met and the entry action has been executed for 10 minutes (first preset time). After that, exit control, close the first flow control valve 9, and determine the conditions for the next entry.

[0174] ① The superheat of the first heat exchanger 1 is ≤2℃ (second preset temperature) Furthermore, the opening degree of the second flow control valve 8 is ≤0.4. (Third preset opening) ).

[0175] ② The temperature difference at the outlet of the second heat exchanger 2 (the temperature change calculated from the start of control) ≥ 10℃ (third preset temperature) ); and the temperature difference at the inlet of the second heat exchanger 2 (the temperature change calculated from the start of control) ≥ 6℃ (fourth preset temperature). ).

[0176] ③ The action has been performed for 10 minutes (first preset time) Automatic exit.

[0177] 4. Exit action: The opening of the first flow control valve 9 is closed to 0.

[0178] Control scheme two: The first flow control valve 9 is opened at fixed times. The high-pressure gas pipe 5 and the second heat exchanger 2 are used as liquid storage tanks. By identifying the number of indoor units and the number of times they are turned on and off, the opening and closing of the first flow control valve 9 is controlled at fixed times.

[0179] In some short-pipe systems or with fewer three-pipe indoor units, the liquid refrigerant stored on the second heat exchanger 2 side is less due to the shorter pipes, making it difficult for the system to enter the control scheme one mentioned above. In this case, control scheme two can be used to periodically open the first flow control valve 9 to release the refrigerant in the second heat exchanger 2.

[0180] At this point, it is necessary to distinguish whether there is one or more three-pipe indoor units that are not turned on when the indoor units are turned on. If so, the first flow control valve 9 of the three-pipe indoor units that are not turned on can be fully opened to allow the refrigerant to flow. Since the user is not using them, it will not affect the user.

[0181] 1. Identify the number of three-pipe indoor units in the air conditioning system. If there is only a single three-pipe indoor unit, that three-pipe indoor unit is turned on. Or if there are multiple three-pipe indoor units and all of them are turned on, control them as follows.

[0182] 1. Entry conditions: The three-pipe indoor unit is started, and the three-pipe indoor unit has been running for 1 hour (third preset time). (It has been verified in the laboratory with the longest connecting pipe that when the first flow control valve 9 is closed, the liquid refrigerant can basically fill the high-pressure gas pipe within 1 hour, so the first flow control valve 9 is set to be opened once every 1 hour).

[0183] 2. Action: The first flow control valve 9 opens to the first preset opening degree. .

[0184] 3. Exit condition: The first flow control valve 9 is opened to the first preset opening degree. The action is executed for 10 minutes (first preset time). ).

[0185] 4. Exit action: First flow control valve 9 is closed.

[0186] Every 1 hour (third preset time) Enter the execution action.

[0187] 2. Identify the number of three-pipe indoor units in the air conditioning system. If the number of three-pipe indoor units is greater than or equal to two, and the number of three-pipe indoor units in operation is less than or equal to the total number of three-pipe indoor units minus 1, then control as follows.

[0188] 1. Judgment conditions: The three-pipe indoor unit is started, and the three-pipe indoor unit has been running for 1 hour (third preset time). (It has been verified in the laboratory with the longest connecting pipe that when the first flow control valve 9 is closed, the liquid refrigerant can basically fill the high-pressure gas pipe within 1 hour, so the first flow control valve 9 is set to be opened once every 1 hour).

[0189] 2. Action: The first flow control valve 9 of the three-pipe indoor unit, which is shut down, opens to its maximum opening degree. (If the three-pipe indoor unit is not turned on, opening the first flow control valve 9 will not affect the user.) When the three-pipe indoor unit is turned on, the first flow control valve 9 is at the first preset opening degree. .

[0190] 3. Exit condition: The first flow control valve 9 is opened to the first preset opening degree. The action is executed for 10 minutes (first preset time). ).

[0191] 4. Exit Action: When the three-pipe indoor unit is on, the first flow control valve 9 closes; when the three-pipe indoor unit is off, the first flow control valve 9 remains at its maximum opening. .

[0192] Every 1 hour (third preset time) Enter the execution action.

[0193] Control scheme 3: Use the outdoor unit's subcooling as a judgment criterion

[0194] By judging the changes in the subcooling and high pressure of the outdoor unit, it is determined whether the system is short of refrigerant. This allows the opening and closing of the first flow control valve 9 of the three-pipe indoor unit to continuously liquefy, store, and release the refrigerant in the second heat exchanger 2. Since the temperature of the condensed refrigerant is close to the indoor ambient temperature, the cold air evaporating from the first heat exchanger 1 is not affected by the high temperature of the refrigerant in the second heat exchanger 2, thus solving the problem of high air outlet temperature of the indoor unit.

[0195] According to the control principle of control scheme one, detecting the superheat of the indoor unit and the opening degree of the second flow control valve 8 are the entry conditions for control. Alternatively, the entry condition can be based on changes in parameters in the outdoor unit. Because refrigerant exists on the high-pressure side, during normal cooling operation, the high pressure and subcooling of the outdoor unit will decrease due to refrigerant shortage. Using this as a judgment condition, after 15 minutes of detection, if the condition is met, control is initiated, and the first flow control valve 9 is opened to the first preset opening degree. When the outdoor unit's subcooling level rises and the inlet and outlet pipe temperatures of the indoor unit's second heat exchanger 2 change, the system exits the execution action; or, if the first flow control valve 9 has been open for 10 minutes, it automatically closes the first flow control valve 9.

[0196] Compressor starts 1 hour (fourth preset time) After that, the following controls are performed.

[0197] 1. Judgment criteria: Continuous detection for 15 minutes (fifth preset time) ).

[0198] ① The compressor output remains constant (if the compressor output changes, the pressure changes, making it impossible to determine effectively), and the saturation temperature difference corresponding to the outlet pressure of compressor 10 is ≥2℃ (fifth preset temperature). ).

[0199] ② Subcooling (Ta-Tb) ≤ 6℃ (Sixth preset temperature) ).

[0200] 2. Action: The first flow control valve 9 opens to the first preset opening degree. .

[0201] 3. Exit conditions: You can exit if any of the following conditions are met.

[0202] ① Subcooling (the difference between the saturation temperature corresponding to the outlet pressure of compressor 10 and the outlet temperature of condenser 11) ≥ 10℃ (seventh preset temperature) Furthermore, the saturation temperature difference corresponding to the outlet pressure of compressor 10 is ≥2℃ (eighth preset temperature). ).

[0203] ② The temperature difference at the outlet of the second heat exchanger 2 (the temperature change calculated from the start of control) ≥ 10 ℃ (ninth preset temperature) ); and the temperature difference at the inlet of the second heat exchanger 2 (the temperature change calculated from the start of control) ≥ 6℃ (tenth preset temperature). ).

[0204] ③ The first flow control valve 9 has been open for 10 minutes (first preset time) ).

[0205] 4. Exit Action:

[0206] The opening of the first flow control valve 9 is closed to 0.

[0207] The parameter ranges in the embodiments of this disclosure are as follows.

[0208] First preset time The time is 10 min to 15 min, with 10 min being an option.

[0209] Second preset time 8 min to 12 min, 10 min optional.

[0210] Third preset time The duration is 0.5 h to 1 h, with 1 h being an option.

[0211] Fourth preset time The time is 1 h to 2 h, with 1 h being an option.

[0212] Fifth preset time The time is 10 min to 15 min, with 15 min being the optional option.

[0213] First preset opening degree To be determined through experiments.

[0214] Second preset opening degree It is 0.55 ~0.65 Optional 0.6 .

[0215] Third preset opening degree It is 0.35 ~0.45 Optional 0.4 .

[0216] Maximum opening of the first flow control valve .

[0217] Maximum opening of the second flow control valve .

[0218] First preset temperature The temperature range is 4℃ to 6℃, with 5℃ being an option.

[0219] Second preset temperature The temperature range is 1℃ to 3℃, with 2℃ being an option.

[0220] Third preset temperature The temperature range is 8℃ to 10℃, with 10℃ being the optional setting.

[0221] Fourth preset temperature The temperature range is 6℃ to 8℃, with 6℃ being the optional setting.

[0222] Fifth preset temperature The temperature range is 2℃ to 3℃, with 2℃ being the preferred option.

[0223] Sixth preset temperature The temperature range is 5℃ to 7℃, with 6℃ being an option.

[0224] Seventh preset temperature The temperature range is 8℃ to 10℃, with 10℃ being the optional setting.

[0225] Eighth preset temperature The temperature range is 1℃ to 2℃, with 2℃ being an option.

[0226] Ninth preset temperature The temperature range is 8℃ to 10℃, with 10℃ being the optional setting.

[0227] Tenth preset temperature The temperature range is 6℃ to 8℃, with 6℃ being the optional setting.

[0228] Some embodiments of this disclosure also provide an air conditioning system, which includes an indoor unit 100 and a controller 300. The indoor unit 100 includes a first heat exchanger 1 and a second heat exchanger 2. The inlet end of the first heat exchanger 1 is connected to a liquid pipe 3 through a first pipe 6, and the outlet end of the first heat exchanger 1 is connected to a low-pressure gas pipe 4. The inlet end of the second heat exchanger 2 is connected to a high-pressure gas pipe 5, and the outlet end of the second heat exchanger 2 is connected to the first pipe 6 through a second pipe 7. A first flow control valve 9 is provided on the second pipe 7. The controller 300 is electrically connected to the first flow control valve 9, and the controller 300 is configured to implement the control method of the air conditioning system of any of the above embodiments.

[0229] In some embodiments, a second flow control valve 8 is provided on the first pipeline 6. The controller 300 is also electrically connected to the second flow control valve 8.

[0230] In some embodiments, the second flow control valve 8 includes an expansion valve.

[0231] The three-pipe indoor unit consists of two heat exchangers: a first heat exchanger 1 and a second heat exchanger 2. The first heat exchanger 1, acting as the main heat exchanger, is connected in series with a second flow control valve 8. A temperature sensor is installed before and after the first heat exchanger 1. In cooling mode, the first heat exchanger 1 acts as an evaporator, dehumidifying and cooling (when the indoor unit is cooling, the refrigerant in the evaporator exchanges heat with the air, lowering the indoor air temperature; water vapor at the air outlet condenses into water and is discharged from the indoor unit's drip tray, achieving dehumidification). The second heat exchanger 2, acting as a secondary heat exchanger, is connected in series with a first flow control valve 9. A temperature sensor is installed before and after the second heat exchanger 2. In cooling mode, the second heat exchanger 2 acts as a condenser, providing heating.

[0232] In some embodiments, the air conditioning system further includes a third heat exchanger 16, which may be a two-pipe indoor unit connected in parallel with a three-pipe indoor unit.

[0233] In some embodiments, the air conditioning system also includes components such as a subcooler 17, a gas-liquid separator 18, and a four-way valve 19.

[0234] In some embodiments, both the second flow control valve 8 and the first flow control valve 9 are electronic expansion valves.

[0235] Some embodiments of this disclosure also provide a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the control method of any of the above embodiments.

[0236] Based on the embodiments disclosed above, in the absence of explicit denial or conflict, the technical features of one embodiment may be advantageously combined with one or more other embodiments.

[0237] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A control method for an air conditioning system, the air conditioning system comprising an indoor unit (100), the indoor unit (100) comprising a first heat exchanger (1) and a second heat exchanger (2), the inlet end of the first heat exchanger (1) being connected to a liquid pipe (3) via a first pipe (6), the outlet end of the first heat exchanger (1) being connected to a low-pressure gas pipe (4), the inlet end of the second heat exchanger (2) being connected to a high-pressure gas pipe (5), the outlet end of the second heat exchanger (2) being connected to the first pipe (6) via a second pipe (7), the second pipe (7) being provided with a first flow control valve (9), characterized in that, The control method includes the following steps: When the air conditioning system is turned on in cooling mode or switched to cooling mode, the first flow control valve (9) is controlled to close so that refrigerant is stored in the second heat exchanger (2); It also includes the following steps: controlling the first flow control valve (9) to open at regular intervals or at irregular intervals, so that when the first flow control valve (9) is opened, the second heat exchanger (2) releases the refrigerant stored therein.

2. The control method for the air conditioning system according to claim 1, characterized in that, It also includes the following steps: Control the first flow control valve (9) to a first preset opening degree. Turn on, and the first preset time is reached after the turn-on time. Then it is closed so that the second heat exchanger (2) releases refrigerant and then stores refrigerant.

3. The control method for the air conditioning system according to claim 1, characterized in that, A second flow control valve (8) is provided on the first pipeline (6), and the control of the opening of the first flow control valve (9) at irregular intervals includes: Based on the superheat of the first heat exchanger (1) and the opening degree of the second flow control valve (8), determine whether to open the first flow control valve (9).

4. The control method for the air conditioning system according to claim 3, characterized in that, Based on the superheat of the first heat exchanger (1) and the opening degree of the second flow control valve (8), determine whether to open the first flow control valve (9), including: The superheat of the first heat exchanger (1) is greater than or equal to the first preset temperature. ;and, The opening degree of the second flow control valve (8) is ≥ the second preset opening degree. ; Control the first flow control valve (9) to open.

5. The control method for the air conditioning system according to claim 3 or 4, characterized in that, The method of controlling the opening of the first flow control valve (9) at irregular intervals also includes: Second preset time The system continuously detects and opens the first flow control valve (9) after the opening conditions of the first flow control valve (9) are continuously met.

6. The control method for the air conditioning system according to claim 3, characterized in that, The method of controlling the opening of the first flow control valve (9) at irregular intervals also includes: Based on the superheat of the first heat exchanger (1), the opening degree of the second flow control valve (8), the temperature difference at the outlet of the second heat exchanger (2) and the temperature difference at the inlet of the second heat exchanger (2), determine whether to close the first flow control valve (9).

7. The control method for an air conditioning system according to claim 6, characterized in that, The step of determining whether to close the first flow control valve (9) based on the superheat of the first heat exchanger (1), the opening degree of the second flow control valve (8), the temperature difference at the outlet of the second heat exchanger (2), and the temperature difference at the inlet of the second heat exchanger (2) includes: When the superheat of the first heat exchanger (1) is less than or equal to the second preset temperature Furthermore, the opening degree of the second flow control valve (8) is ≤ the third preset opening degree. ;as well as After the first flow control valve (9) is opened, the temperature difference at the outlet of the second heat exchanger (2) is greater than or equal to the third preset temperature. And the temperature difference at the inlet of the second heat exchanger (2) is ≥ the fourth preset temperature. ; The first flow control valve (9) is closed.

8. The control method for an air conditioning system according to claim 1 or 2, characterized in that, Controlling the opening of the first flow control valve (9) at regular intervals includes: When there is at least one indoor unit (100) and all of the indoor units (100) are turned on, the third preset time is reached when the turn-on time is reached. Then, control the first flow control valve (9) to open.

9. The control method for an air conditioning system according to claim 1, characterized in that, Controlling the opening of the first flow control valve (9) at regular intervals also includes: When there are at least two indoor units (100), and not all of the indoor units (100) are turned on, the third preset time is reached when the turn-on time is reached. back, The first flow control valve (9) of the indoor unit (100) that controls the start-up is at a first preset opening degree. Turn on; The first flow control valve (9) of the indoor unit (100) that is not turned on is opened to its maximum degree. Start.

10. The control method for an air conditioning system according to claim 9, characterized in that, The method of controlling the opening of the first flow control valve (9) at regular intervals further includes: The first flow control valve (9) of the indoor unit (100) that controls the start-up is at a first preset opening degree. Start-up time reaches the first preset time Close later; The first flow control valve (9) of the indoor unit (100) that is not turned on maintains its maximum opening. Start.

11. The control method for an air conditioning system according to claim 1, wherein the air conditioning system includes an outdoor unit (200), the outdoor unit (200) including a compressor (10) and a condenser (11); characterized in that, The control of the opening of the first flow control valve (9) at irregular intervals includes: Based on the saturation temperature corresponding to the outlet pressure of the compressor (10) and the outlet temperature of the condenser (11), determine whether to open the first flow control valve (9).

12. The control method for an air conditioning system according to claim 11, characterized in that, Based on the saturation temperature corresponding to the outlet pressure of the compressor (10) and the outlet temperature of the condenser (11), determine whether to open the first flow control valve (9), including: When the compressor (10) starts running for the fourth preset time... Then, at the fifth preset time Continuous internal monitoring is performed, and the saturation temperature corresponding to the outlet pressure of the compressor (10) is monitored for a fifth preset time. The difference within ≥ the fifth preset temperature ;and The difference between the saturation temperature corresponding to the outlet pressure of the compressor (10) and the outlet temperature of the condenser (11) is ≤ the sixth preset temperature. , Control the first flow control valve (9) to open.

13. The control method for an air conditioning system according to claim 11, characterized in that, The method of controlling the opening of the first flow control valve (9) at irregular intervals also includes: Based on the saturation temperature corresponding to the outlet pressure of the compressor (10), the outlet temperature of the condenser (11), the temperature difference between the outlet end of the second heat exchanger (2) and the temperature difference between the inlet end of the second heat exchanger (2), determine whether to close the first flow control valve (9).

14. The control method for an air conditioning system according to claim 13, characterized in that, The step of determining whether to close the first flow control valve (9) based on the saturation temperature corresponding to the outlet pressure of the compressor (10), the outlet temperature of the condenser (11), and the temperature difference between the outlet end and the inlet end of the second heat exchanger (2), includes: After the first flow control valve (9) is opened, it will be closed after one of the following three conditions is met: The saturation temperature difference corresponding to the outlet pressure of compressor (10) is ≥ the seventh preset temperature. Furthermore, the difference between the saturation temperature corresponding to the outlet pressure of the compressor (10) and the outlet temperature of the condenser (11) is greater than or equal to the eighth preset temperature. ; The outlet temperature difference of the second heat exchanger (2) is ≥ the ninth preset temperature. And the temperature difference at the inlet of the second heat exchanger (2) is ≥ the tenth preset temperature. ; The first flow control valve (9) is at a first preset opening degree It is turned on, and the turn-on time reaches the first preset time. .

15. An air conditioning system, characterized in that, The system includes an indoor unit (100) and a controller (300). The indoor unit (100) includes a first heat exchanger (1) and a second heat exchanger (2). The inlet end of the first heat exchanger (1) is connected to a liquid pipe (3) via a first pipe (6). The outlet end of the first heat exchanger (1) is connected to a low-pressure gas pipe (4). The inlet end of the second heat exchanger (2) is connected to a high-pressure gas pipe (5). The outlet end of the second heat exchanger (2) is connected to the first pipe (6) via a second pipe (7). A first flow control valve (9) is provided on the second pipe (7). The controller (300) is electrically connected to the first flow control valve (9). The controller (300) is configured to implement the control method of the air conditioning system according to any one of claims 1 to 14.

16. A computer-readable storage medium, characterized in that, It stores a computer program, which, when executed by a processor, implements the control method as described in any one of claims 1 to 14.

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