Heat exchanger control system and method, air conditioner indoor unit and air conditioner

Abstract

The invention provides a heat exchanger control system and method, an air conditioner indoor unit and an air conditioner, the heat exchanger control system is arranged on heat exchange equipment, the heat exchanger control system comprises a flow path structure, the flow path structure is provided with a plurality of heat exchange pipes, and the heat exchange pipes form a direct flow path or a branch flow path for refrigerant circulation; the control structure is connected with the flow path structure; the control structure is used for controlling the flow path structure to be switched to the direct-current flow path or the branch flow path; and when the control structure controls the flow path structure to be switched to the direct flow path, the multiple heat exchange pipes are sequentially connected so as to form a single circulation path for a refrigerant to flow. By means of the heat exchanger control system, the technical problem that in the prior art, the flow path design of an indoor unit heat exchanger in a variable frequency air conditioner cannot achieve balance between efficient heat exchange and system pressure drop, and consequently the variable frequency air conditioner is difficult to give consideration to high efficiency and comfort at the same time under different working conditions can be effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and in particular to a heat exchanger control system, method, air conditioner indoor unit and air conditioner. Background Art

[0002] At present, variable frequency air conditioners have become the mainstream products in the home and commercial air conditioning markets. In order to meet users' needs for comfort, this type of air conditioner is usually designed with multiple operating gears. For example, in cooling mode, air conditioners usually have high, medium, low and ultra-high air volume gears to meet the needs of different ambient temperatures. These gears not only correspond to different air volumes, but also to different refrigerant flows. As users' requirements for energy saving and comfort increase, the intelligence and precise control capabilities of variable frequency air conditioners are also constantly improving.

[0003] However, the optimal flow path design of the indoor unit heat exchanger is different in different operating modes of the variable frequency air conditioner. For example, in cooling mode, a flow path design may be required to maximize the heat exchange efficiency of the refrigerant, while in heating mode, another design may be required to reduce the system pressure drop. Therefore, the flow path design of the indoor unit heat exchanger needs to strike a balance between efficient heat exchange and system pressure drop. However, due to design limitations, designers can usually only optimize for a certain working condition, but not all working conditions at the same time. This design that is biased towards a certain working condition will result in limited performance under other working conditions, making it impossible to achieve the best cooling effect or energy efficiency ratio. Moreover, this design limitation makes it impossible for the variable frequency air conditioner to ensure heat exchange efficiency under different working conditions, which in turn affects the heat exchange capacity of the indoor unit heat exchanger, and ultimately makes it difficult for the variable frequency air conditioner to simultaneously take into account high efficiency and comfort under different working conditions.

[0004] Therefore, the prior art needs to be further developed. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned technical deficiencies and provide a heat exchanger control system, method, air-conditioning indoor unit and air conditioner to solve the technical problem that the flow path design of the indoor unit heat exchanger in the variable frequency air conditioner in the prior art cannot achieve a balance between efficient heat exchange and system pressure drop, resulting in the variable frequency air conditioner being difficult to simultaneously take into account high efficiency and comfort under different working conditions.

[0006] To achieve the above technical purpose, according to one aspect of the present invention: a heat exchanger control system is provided, the heat exchanger control system is arranged on the heat exchange equipment, the heat exchanger control system includes: a flow path structure, the flow path structure has a plurality of heat exchange tubes, and the plurality of heat exchange tubes are used to form a direct flow path or a branch flow path for the refrigerant to flow; a control structure, connected to the flow path structure; the control structure is used to control the flow path structure to switch to a direct flow path or a branch flow path; wherein, when the control structure controls the flow path structure to switch to a direct flow path, the plurality of heat exchange tubes are connected in sequence to form a single flow path for the refrigerant to flow; when the control structure controls the flow path structure to switch to a branch flow path, at least two of the plurality of heat exchange tubes are divided into at least two parallel branches to form at least two flow paths for the refrigerant to flow.

[0007] Furthermore, the heat exchanger control system also includes: a liquid distributor, which is connected to the input part of the flow path structure, and the refrigerant flows into the flow path structure through the liquid distributor; or, the refrigerant flows into the liquid distributor through the flow path structure; a gas collecting pipe, which is respectively connected to the output part of the flow path structure, and the gas collecting pipe is used to collect the refrigerant flowing out of the flow path structure; or, the gas collecting pipe is used to transport the refrigerant into the flow path structure; wherein, the output part of the flow path structure has a first output end and a second output end, and the first output end of the flow path structure and the second output end of the flow path structure are both connected to the gas collecting pipe in a disconnectable manner; when the control structure controls the flow path structure to switch to a direct current flow path, the first output end of the flow path structure is in a connected state with the gas collecting pipe, and the second output end of the flow path structure is in a disconnected state with the gas collecting pipe; when the control structure controls the flow path structure to switch to a branch flow path, the first output end of the flow path structure is in a disconnected state with the gas collecting pipe, and the second output end of the flow path structure is in a connected state with the gas collecting pipe.

[0008] Furthermore, multiple heat exchange tubes constitute a first branch, a second branch and a third branch; the first end of the first branch forms an input part of the flow path structure, the second end of the first branch is connected to the first end of the second branch in an on-off manner, and the first end of the second branch is connected to the gas collecting pipe in an on-off manner; the second end of the second branch is connected to the second end of the third branch; the first end of the third branch is connected to the second end of the first branch; wherein, when the control structure controls the flow path structure to switch to a direct current flow path, the first end of the second branch is in a disconnected state from the second end of the first branch; and the first end of the second branch is in a connected state with the gas collecting pipe.

[0009] Furthermore, the flow path structure also includes: a connecting pipe, the first end of the connecting pipe is respectively connected to the second end of the second branch and the second end of the third branch; the second end of the connecting pipe is used to form a second output end of the flow path structure; wherein, when the control structure controls the flow path structure to switch to the branch flow path, the first end of the second branch is in a connected state with the second end of the first branch; the first end of the second branch is in a disconnected state with the gas collecting pipe; the second end of the connecting pipe is in a connected state with the gas collecting pipe.

[0010] Furthermore, the flow path structure also includes: a first control valve, which is arranged between the second end of the first branch and the first end of the second branch, and the first control valve is respectively connected to the second end of the first branch and the first end of the second branch; the first control valve is used to control the on-off between the second end of the first branch and the first end of the second branch; the control structure is connected to the first control valve, and the control structure is used to control the opening and closing of the first control valve; wherein, when the control structure controls the flow path structure to switch to the branch flow path, the control structure controls the first control valve to open; when the control structure controls the flow path structure to switch to the direct flow path, the control structure controls the first control valve to close.

[0011] Furthermore, the gas collecting pipe includes: a first gas collecting branch and a second gas collecting branch, the first end of the first gas collecting branch is connected to the first end of the second branch, and the first end of the second gas collecting branch is connected to the second end of the connecting pipe; a gas collecting main line, the second end of the first gas collecting branch and the second end of the second gas collecting branch are both connected to the gas collecting main line in a switchable manner; wherein the first gas collecting branch and the second gas collecting branch are arranged in parallel.

[0012] Furthermore, the heat exchanger control system also includes: a second control valve, which is arranged on the first gas collecting branch, and the second control valve is used to control the on-off of the first gas collecting branch and the gas collecting main line; a control structure is connected to the second control valve, and the control structure is used to control the on-off of the second control valve; wherein, when the control structure controls the flow path structure to switch to the direct flow path, the control structure controls the second control valve to open; when the control structure controls the flow path structure to switch to the branch flow path, the control structure controls the second control valve to close.

[0013] Furthermore, the heat exchanger control system also includes: a third control valve, which is arranged on the second gas collecting branch; the third control valve is used to control the on-off of the second gas collecting branch and the gas collecting main line; the control structure is connected to the third control valve, and the control structure is used to control the on-off of the third control valve; wherein, when the control structure controls the flow path structure to switch to the direct flow path, the control structure controls the third control valve to close; when the control structure controls the flow path structure to switch to the branch flow path, the control structure controls the third control valve to open.

[0014] According to another aspect of the present invention, an air-conditioning indoor unit is provided, comprising: a heat exchanger control system, and the heat exchanger control system is the above-mentioned heat exchanger control system.

[0015] According to another aspect of the present invention, an air conditioner is provided, comprising: an air conditioner indoor unit, wherein the air conditioner indoor unit is the air conditioner indoor unit described above.

[0016] According to another aspect of the present invention: a control method is provided, characterized in that the control method is applied to the above-mentioned heat exchanger control system, and the control method includes: obtaining the operating mode of the heat exchange device; and controlling the flow path structure to switch to a direct flow path or a branch flow path according to the current operating mode of the heat exchange device; wherein the direct flow path forms a single flow path for the refrigerant to flow; and the branch flow path forms at least two parallel flow paths for the refrigerant to flow.

[0017] Furthermore, a method for controlling the flow path structure to switch to a direct flow path or a branch flow path according to the current operating mode of the heat exchange device includes: if the heat exchange device is in a heating mode, controlling the flow path structure to switch to a direct flow path; if the heat exchange device is in a cooling mode or other modes, calculating the current refrigerant flow m3; and according to the current refrigerant flow m3, controlling the flow path structure to switch to a direct flow path or a branch flow path.

[0018] Furthermore, a method for controlling the flow path structure to switch to a direct flow path or a branch flow path according to the current refrigerant flow m3 includes: if the current refrigerant flow m3 is greater than or equal to the first preset threshold value m1, controlling the flow path structure to switch to the branch flow path; if the current refrigerant flow m3 is less than or equal to the second preset threshold value m2, controlling the flow path structure to switch to the direct flow path; if the current refrigerant flow m3 is less than the first preset threshold value m1 and greater than the second preset threshold value m2, controlling the flow path structure to maintain the direct flow path or the branch flow path; wherein, m1>m2.

[0019] Further, the heat exchange device includes a compressor; if the heat exchange device is in a cooling mode or other modes, the method for calculating the current refrigerant flow rate m3 includes: obtaining the operating frequency f, the compressor displacement Vd and the volumetric efficiency η, and the refrigerant specific volume ν at the suction port of the compressor; calculating the current refrigerant flow rate m3 by the obtained operating frequency f, the compressor displacement Vd, the volumetric efficiency η and the refrigerant specific volume ν; the calculation formula is: .

[0020] Beneficial effects: The technical solution of the present invention is applied, and the heat exchanger control system provided by the present invention is provided with a flow path structure and a control structure, and the flow path structure has a plurality of heat exchange tubes, and the plurality of heat exchange tubes can be combined into a direct flow path or a branch flow path for the circulation of refrigerant according to different working conditions. The control structure is connected to the flow path structure, and the control structure is used to control the flow path structure to switch to a direct flow path or a branch flow path, that is, the control structure switches the configuration of the flow path structure according to the operation mode of the heat exchange device. Among them, when the flow path structure is switched to a direct flow path, each heat exchange tube can be connected in series in sequence to form a single flow path for the circulation of refrigerant. At this time, when the refrigerant enters the flow path structure, it will pass through each heat exchange tube in sequence along this single flow path for heat exchange, and then flow out from the flow path structure. When the flow path structure is switched to a branch flow path, at least two heat exchange tubes in each heat exchange tube will be divided into two parallel branches, that is, at least two heat exchange tubes in each heat exchange tube will be arranged in parallel, so that it becomes at least two parallel branches, thereby forming at least two flow paths for the circulation of refrigerant. At this time, when the refrigerant enters the flow path structure, the refrigerant will flow into at least two parallel branches, and exchange heat with at least one heat exchange tube in each branch. Then, the refrigerant flows out through the output ends of each branch and converges together to flow out from the flow path structure. It can be seen that the flow path structure has different flow path modes, namely direct flow path and branch flow path, so that the heat exchanger can achieve a variable flow path. This design enables the heat exchanger to flexibly select the flow path under different working conditions, thereby improving the system's adaptability to changes. In addition, the flexibility of the flow path enables the heat exchanger to match the optimal flow path under different conditions, thereby improving the heat exchange efficiency and overall energy efficiency. The flexible connection method between multiple heat exchange tubes enables the flow path of the refrigerant to be adjusted according to demand, ideally adapting to different load conditions. At the same time, the control structure can automatically control the flow path structure to switch to a direct flow path or a branch flow path, so that the heat exchanger can automatically select the optimal flow path according to the actual operating conditions, so that the heat exchanger can provide the best heat exchange performance under various environmental conditions, minimize pressure loss, and avoid the high energy consumption and lack of comfort caused by the traditional single design. And by precisely controlling the heat exchange process, the system can provide a stable and comfortable indoor environment regardless of high load or low load. At the same time, the optimized flow path design and control can also reduce equipment wear caused by excessive pressure and insufficient heat exchange, reduce the failure rate and extend the service life of the equipment. In addition, while improving energy utilization and reducing energy consumption, the system can also reduce greenhouse gas emissions, which is in line with the trend of green environmental protection and has significant economic and environmental value. The heat exchanger control system of the present invention can effectively solve the technical problem that the flow path design of the indoor unit heat exchanger in the variable frequency air conditioner in the prior art cannot achieve a balance between efficient heat exchange and system pressure drop, resulting in the variable frequency air conditioner being difficult to simultaneously take into account high efficiency and comfort under different working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic structural diagram of an embodiment of a heat exchanger control system of the present invention is shown; Figure 2 A schematic diagram showing a structure in which each flow path structure in an embodiment of a heat exchanger control system of the present invention is a direct current flow path; Figure 3 A schematic diagram showing a structure in which each flow path structure in an embodiment of a heat exchanger control system of the present invention is a branch flow path; Figure 4 A schematic diagram showing the connection between the flow path structure and the gas collecting pipe in an embodiment of the heat exchanger control system of the present invention is shown; Figure 5 A flow chart showing an embodiment of the control method of the present invention is shown.

[0022] The above drawings include the following reference numerals: 1. Flow path structure; 11. Heat exchange tube; 12. First branch; 13. Second branch; 14. Third branch; 15. Connecting pipeline; 16. First control valve; 2. Liquid distribution pipe; 3. Gas collecting pipe; 31. First gas collecting branch; 32. Second gas collecting branch; 33. Gas collecting main line; 4. Second control valve; 5. Third control valve. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0024] See also Figures 1 to 4 As shown, according to an embodiment of the present invention, the present invention provides a heat exchanger control system, which is arranged on a heat exchange device, and the heat exchanger control system includes: a flow path structure 1 and a control structure, the flow path structure 1 has a plurality of heat exchange tubes 11, and the plurality of heat exchange tubes 11 are used to form a direct flow path or a branch flow path for the refrigerant to flow; the control structure is connected to the flow path structure 1, and the control structure is used to control the flow path structure 1 to switch to a direct flow path or a branch flow path; wherein, when the control structure controls the flow path structure 1 to switch to a direct flow path, the plurality of heat exchange tubes 11 are connected in sequence to form a single flow path for the refrigerant to flow; when the control structure controls the flow path structure 1 to switch to a branch flow path, at least two of the plurality of heat exchange tubes 11 are divided into at least two parallel branches to form at least two flow paths for the refrigerant to flow.

[0025] It can be seen that the heat exchanger control system provided by the present invention is provided with a flow path structure 1 and a control structure, wherein the flow path structure 1 has a plurality of heat exchange tubes 11, and the plurality of heat exchange tubes 11 can be combined into a direct flow path or a branch flow path for the circulation of refrigerant according to different working conditions. The control structure is connected to the flow path structure 1, and the control structure is used to control the flow path structure 1 to switch to a direct flow path or a branch flow path (that is, the control structure switches the configuration of the flow path structure 1 according to the operating mode of the heat exchange device). Among them, when the flow path structure 1 is switched to a direct flow path, each heat exchange tube 11 can be connected in sequence (each heat exchange tube 11 is connected in series), thereby forming a single circulation path for the circulation of refrigerant. At this time, when the refrigerant enters the flow path structure 1, it will pass through each heat exchange tube 11 in sequence along this single circulation path for heat exchange, and then flow out from the flow path structure 1. When the flow path structure 1 is switched to a branch flow path, at least two heat exchange tubes 11 in each heat exchange tube 11 will be divided into two parallel branches (that is, at least two heat exchange tubes 11 in each heat exchange tube 11 will be arranged in parallel, so that it becomes at least two parallel branches), thereby forming at least two flow paths for the refrigerant to circulate. At this time, when the refrigerant enters the flow path structure 1, the refrigerant will flow into at least two parallel branches, and exchange heat with at least one heat exchange tube 11 in each branch. Then, the refrigerant flows out through the output ends of each branch and converges together, and flows out from the flow path structure 1. It can be seen that the flow path structure 1 has different flow path modes (that is, direct flow path and branch flow path), so that the heat exchanger can realize variable flow path. This design enables the heat exchanger to flexibly select the flow path under different working conditions, thereby improving the system's adaptability to changes. In addition, the flexibility of the flow path enables the heat exchanger to match the optimal flow path under different conditions, thereby improving the heat exchange efficiency and overall energy efficiency. The flexible connection between the multiple heat exchange tubes 11 enables the flow path of the refrigerant to be adjusted according to demand, ideally adapting to different load conditions. At the same time, the control structure can automatically control the flow path structure 1 to switch to a direct flow path or a branch flow path, so that the heat exchanger can automatically select the optimal flow path according to the actual operating conditions, so that the heat exchanger can provide the best heat exchange performance under various environmental conditions, minimize pressure loss, and avoid the high energy consumption and insufficient comfort caused by the traditional single design. And by accurately controlling the heat exchange process, the system can provide a stable and comfortable indoor environment regardless of high load or low load. At the same time, the optimized flow path design and control can also reduce equipment wear caused by excessive pressure and insufficient heat exchange, reduce the occurrence rate of failures and extend the service life of the equipment. In addition, while improving energy utilization and reducing energy consumption, the system can also reduce greenhouse gas emissions, which is in line with the trend of green environmental protection and has significant economic and environmental value.The heat exchanger control system of the present invention can effectively solve the technical problem that the flow path design of the indoor unit heat exchanger in the variable frequency air conditioner in the prior art cannot achieve a balance between efficient heat exchange and system pressure drop, resulting in the variable frequency air conditioner being difficult to simultaneously take into account high efficiency and comfort under different working conditions.

[0026] Optionally, the heat exchange device may be an air conditioner, or a heat pump unit or other equipment.

[0027] Specifically, Figures 1 to 3As shown, the heat exchanger control system also includes: a liquid distributor 2 and an air collector 3, the liquid distributor 2 is connected to the input part of the flow path structure 1, and the refrigerant flows into the flow path structure 1 through the liquid distributor 2; or, the refrigerant flows into the liquid distributor 2 through the flow path structure 1; the air collector 3 is respectively connected to the output part of the flow path structure 1, and the air collector 3 is used to collect the refrigerant flowing out of the flow path structure 1; or, the air collector 3 is used to transport the refrigerant into the flow path structure 1. Among them, the output part of the flow path structure 1 has a first output end and a second output end, and the first output end of the flow path structure 1 and the second output end of the flow path structure 1 are both connected to the gas collecting pipe 3 in an on-off manner; when the control structure controls the flow path structure 1 to switch to the direct flow path, the first output end of the flow path structure 1 is in a connected state with the gas collecting pipe 3, and the second output end of the flow path structure 1 is in a disconnected state with the gas collecting pipe 3; when the control structure controls the flow path structure 1 to switch to the branch flow path, the first output end of the flow path structure 1 is in a disconnected state with the gas collecting pipe 3, and the second output end of the flow path structure 1 is in a connected state with the gas collecting pipe 3. With such a structural setting, the flow rate of the refrigerant entering the flow path structure 1 can be controlled by setting the liquid distributor 2 and the gas collecting pipe 3, thereby ensuring the appropriate amount of refrigerant to optimize the heat exchange efficiency. In addition, the liquid distributor 2 can promote the uniform distribution of the refrigerant, making the system run more smoothly and improving the refrigeration efficiency. Or it can be responsible for collecting the refrigerant flowing out of the flow path structure 1 to ensure that it can be effectively discharged and improve the efficiency of the system cycle. And it can help stabilize the pressure and flow in the system, thereby improving the overall performance and avoiding system failures caused by pressure fluctuations. And timely collect and recycle refrigerant to ensure the continuity of the flow of refrigerant in the system, thereby improving the refrigeration and heat exchange efficiency. In addition, when the control structure controls the flow path structure 1 to switch to the branch flow path, the first output end of the flow path structure 1 is disconnected from the gas collecting pipe 3, and the second output end of the flow path structure 1 is connected to the gas collecting pipe 3, so that the refrigerant from each branch is gathered at the second output end of the flow path structure 1 and flows into the gas collecting pipe 3. Then in the branch flow path mode, the refrigerant can be gathered from multiple branches to one output end, which is convenient for flexible distribution of the flow. In this way, the flow direction can be adjusted according to different load requirements to improve the adaptability of the system. By converging the refrigerant from different branches to the gas collecting pipe 3, it is ensured that the refrigerant can effectively improve the condensation efficiency during the collection process, maximize the use of the heat exchange capacity of the refrigerant, and thus improve the overall refrigeration efficiency. Converging the refrigerants of different branches at one outlet can more conveniently monitor the system status, quickly collect and analyze the operating data of the system, and facilitate fault detection and maintenance.

[0028] Optionally, when the control structure controls the flow path structure 1 to switch to a direct flow path, the refrigerant flowing out of the liquid distributor 2 enters the flow path structure 1 through the input portion of the flow path structure 1, and then the refrigerant passes through each heat exchange tube 11 in sequence along this single flow path for heat exchange, and then flows into the gas collecting pipe 3 from the first output end of the flow path structure 1. When the control structure controls the flow path structure 1 to switch to a branch flow path, the refrigerant flowing out of the liquid distributor 2 enters the flow path structure 1 through the input portion of the flow path structure 1, and then the refrigerant flows into at least two parallel branches, and exchanges heat with at least one heat exchange tube 11 in each branch, and then the refrigerant is collected at the second output end of the flow path structure 1 through the output ends of each branch, and finally flows into the gas collecting pipe 3 through the second output end of the flow path structure 1.

[0029] Furthermore, there are multiple flow path structures 1, and the multiple flow path structures 1 are arranged in parallel. The input part of each flow path structure 1 is connected to the liquid distribution pipe 2, and the output part of each flow path structure 1 is connected to the gas collecting pipe 3.

[0030] Furthermore, the heat exchanger control system further comprises fins, which are sleeved on each heat exchange tube 11 of each flow path structure 1 .

[0031] Specifically, Figure 4 As shown, a plurality of heat exchange tubes 11 constitute a first branch 12, a second branch 13 and a third branch 14; the first end of the first branch 12 forms the input part of the flow path structure 1, the second end of the first branch 12 is connected to the first end of the second branch 13 in an on-off manner, and the first end of the second branch 13 is connected to the gas collecting pipe 3 in an on-off manner; the second end of the second branch 13 is connected to the second end of the third branch 14; the first end of the third branch 14 is connected to the second end of the first branch 12; wherein, when the control structure controls the flow path structure 1 to switch to a direct current flow path, the first end of the second branch 13 is disconnected from the second end of the first branch 12; the first end of the second branch 13 is connected to the gas collecting pipe 3. With such a structural setting, a plurality of heat exchange tubes 11 constitute the first branch 12, the second branch 13 and the third branch 14, and the flow path can be flexibly switched by combining different branches to meet different cooling or heating needs. This flexibility enables the system to be adjusted according to the instantaneous load. Through the rational design of multiple branches, the flow path of the fluid can be optimized, the flow resistance can be reduced, the flow characteristics can be improved, the energy loss can be reduced, and the overall performance can be improved. In this way, the system can better adapt to different working conditions and load requirements in a changing working environment, and flexibly adjust to ensure the efficiency and safety of the system operation.

[0032] Further, when the control structure controls the flow path structure 1 to switch to the direct flow path, the refrigerant can flow to the gas collecting pipe 3 through the liquid distribution pipe 2, the first branch 12, the third branch 14 and the second branch 13 in sequence. The refrigerant liquid can flow to the liquid distribution pipe 2 through the gas collecting pipe 3, the second branch 13, the third branch 14 and the first branch 12 in sequence.

[0033] Furthermore, no matter the flow path structure 1 is in a direct flow path or a branch flow path, the first end of the third branch 14 and the second end of the first branch 12 are always in a connected state, and the second end of the third branch 14 and the second end of the second branch 13 are always in a connected state.

[0034] Optionally, the first end of the first branch 12 is connected to the liquid dispensing tube 2, and the second end of the first branch 12 is connected to the first end of the second branch 13 in an on-off manner. At the same time, the first end of the second branch 13 is also connected to the gas collecting pipe 3 in an on-off manner, so that the first end of the second branch 13 forms the first output end of the flow path structure 1. In addition, the second end of the first branch 12 is also connected to the first end of the third branch 14, and the second end of the third branch 14 is connected to the second end of the second branch 13. When the control structure controls the flow path structure 1 to switch to the direct current flow path, the first end of the second branch 13 is in a disconnected state with the second end of the first branch 12 (that is, the first end of the second branch 13 is not connected to the second end of the first branch 12), the first end of the third branch 14 is in a connected state with the second end of the first branch 12, the second end of the third branch 14 is in a connected state with the second end of the second branch 13, and the first end of the second branch 13 is in a connected state with the gas collecting pipe 3.

[0035] After passing through the first end of the first branch 12 from the liquid distributor 2, the refrigerant first flows into each heat exchange tube 11 in the first branch 12 in sequence, then flows into each heat exchange tube 11 in the third branch 14, then flows into each heat exchange tube 11 in the second branch 13, and finally flows into the gas collector 3 through the first end of the second branch 13. The refrigerant may also flow through the first end of the second branch 13 from the gas collector 3, first flows into each heat exchange tube 11 in the second branch 13 in sequence, then flows into each heat exchange tube 11 in the third branch 14, then flows into each heat exchange tube 11 in the first branch 12, and finally flows into the liquid distributor 2 through the first end of the first branch 12.

[0036] The first end of the second branch 13 forms the first output end of the flow path structure 1 .

[0037] Optionally, the second end of the first branch 12 has a first outlet and a second outlet, the first end of the second branch 13 has a first inlet and a third outlet, the first outlet is connected to the first inlet in an on-off manner, the second outlet is connected to the first end of the third branch 14 (i.e., the inlet of the third branch 14), and the third outlet of the second branch 13 is connected to the gas collecting pipe 3 in an on-off manner. The second end of the third branch 14 (i.e., the outlet of the third branch 14) is connected to the second end of the second branch 13 (i.e., the fourth outlet of the second branch 13).

[0038] Specifically, Figure 4 As shown, the flow path structure 1 also includes: a connecting pipe 15, the first end of the connecting pipe 15 is connected to the second end of the second branch 13 and the second end of the third branch 14 respectively; the second end of the connecting pipe 15 forms the second output end of the flow path structure 1; wherein, when the control structure controls the flow path structure 1 to switch to the branch flow path, the first end of the second branch 13 is in a connected state with the second end of the first branch 12; the first end of the second branch 13 is in a disconnected state with the gas collecting pipe 3; the second end of the connecting pipe 15 is in a connected state with the gas collecting pipe 3. With such a structural setting, by setting the connecting pipe 15, and the connecting pipe 15 is connected to the second end of the second branch 13 and the second end of the third branch 14 respectively, then in the branch flow path mode, the refrigerant can be gathered from the second end of the second branch 13 and the second end of the third branch 14 into the connecting pipe 15, or the first end of the second branch 13 and the first end of the third branch 14 are gathered into the first branch 12, so as to facilitate the flexible distribution of the flow. In this way, the flow direction can be adjusted according to different load requirements to improve the adaptability of the system. By collecting the refrigerant from different branches (i.e., the second branch 13 and the third branch 14) into the connecting pipe 15 or the first branch 12; then collecting it into the gas collecting pipe 3 through the connecting pipe 15 or collecting it into the liquid distributor 2 through the first branch 12; ensuring that the refrigerant can effectively improve the condensation efficiency during the collection process, maximize the use of the heat exchange capacity of the refrigerant, and thus improve the overall refrigeration efficiency. By collecting the refrigerant from different branches (i.e., the second branch 13 and the third branch 14) into the connecting pipe 15 or the liquid distributor 2, it is easier to monitor the system status, quickly collect and analyze the system operation data, and facilitate fault detection and maintenance.

[0039] Further, when the control structure controls the flow path structure 1 to switch to the branch flow path, the refrigerant is made to flow to the second branch 13 and the third branch 14 respectively after passing through the liquid distributor 2 and the second end of the first branch 12, and to the gas collecting pipe 3 through the connecting pipe 15. Alternatively, the refrigerant is made to flow to the second branch 13 and the third branch 14 respectively after passing through the gas collecting pipe 3 and the connecting pipe 15, and to the liquid distributor 2 through the first branch 12. Optionally, the first end of the first branch 12 is connected to the liquid distributor 2, and the second end of the first branch 12 is connected to the first end of the second branch 13 in a disconnectable manner. At the same time, the first end of the second branch 13 is also connected to the gas collecting pipe 3 in a disconnectable manner, and then the first end of the second branch 13 forms the first output end of the flow path structure 1. In addition, the second end of the first branch 12 is also connected to the first end of the third branch 14; while the second end of the third branch 14 is connected to the second end of the second branch 13, the first end of the connecting pipe 15 is respectively connected to the second end of the third branch 14 and the second end of the second branch 13 (that is, the first end of the connecting pipe 15, the second end of the third branch 14 and the second end of the second branch 13 are connected to each other), and the second end of the connecting pipe 15 is connected to the gas collecting pipe 3 in a disconnectable manner (that is, the second end of the connecting pipe 15 is connected to form a second output end of the flow path structure 1).

[0040] When the control structure controls the flow path structure 1 to switch to the branch flow path, the first end of the second branch 13 is in a connected state with the second end of the first branch 12 (i.e., the first end of the second branch 13 is in communication with the second end of the first branch 12), the first end of the third branch 14 is in a connected state with the second end of the first branch 12, the second end of the third branch 14, the second end of the second branch 13 and the first end of the connecting pipe 15 are in a connected state, and the first end of the second branch 13 is in a disconnected state with the gas collecting pipe 3 (i.e., the first end of the second branch 13 is not in communication with the gas collecting pipe 3). The second end of the connecting pipe 15 is in a connected state with the gas collecting pipe 3.

[0041] After the refrigerant flows from the liquid distributor 2 into the first end of the first branch 12, it first flows into each heat exchange tube 11 in the first branch 12 in sequence, and then flows from the second end of the first branch 12 into each heat exchange tube 11 in the third branch 14 and each heat exchange tube 11 in the second branch 13 respectively. Then, the refrigerant entering the second branch 13 enters the connecting pipe 15 through the second end of the second branch 13 and the first end of the connecting pipe 15. At the same time, the refrigerant entering the third branch 14 enters the connecting pipe 15 through the second end of the third branch 14 and the first end of the connecting pipe 15. Finally, the refrigerant gathered in the connecting pipe 15 flows into the collecting pipe 3 through the second end of the connecting pipe 15. Alternatively, after the refrigerant flows from the gas collecting pipe 3 into the connecting pipe 15, it flows into each heat exchange tube 11 in the third branch 14 and each heat exchange tube 11 in the second branch 13 respectively, and then the refrigerant entering the second branch 13 enters the second end of the first branch 12 through the first end of the second branch 13, and at the same time, the refrigerant entering the third branch 14 enters the second end of the first branch 12 through the first end of the third branch 14 (that is, the refrigerant in the second branch 13 and the refrigerant in the third branch 14 are gathered at the second end of the first branch 12), and then flows into each heat exchange tube 11 in the first branch 12 in sequence, and finally flows to the liquid distributor 2 through the second end of the first branch 12.

[0042] Specifically, Figures 1 to 4 As shown, the flow path structure 1 also includes: a first control valve 16, the first control valve 16 is arranged between the second end of the first branch 12 and the first end of the second branch 13, and the first control valve 16 is connected to the second end of the first branch 12 and the first end of the second branch 13 respectively; the first control valve 16 is used to control the on-off between the second end of the first branch 12 and the first end of the second branch 13; the control structure is connected to the first control valve 16, and the control structure is used to control the opening and closing of the first control valve 16; wherein, when the control structure controls the flow path structure 1 to switch to the branch flow path, the control structure controls the first control valve 16 to open; when the control structure controls the flow path structure 1 to switch to the direct flow path, the control structure controls the first control valve 16 to close. With such a control method, by setting the first control valve 16, the second end of the first branch 12 and the first end of the second branch 13 can be connected on and off, so that the system can quickly switch between the branch flow path and the direct flow path, adjust the flow path according to actual needs, and improve the adaptability of the system. By controlling the opening and closing of the valve, the flow of refrigerant can be managed more effectively, reducing the risk of unnecessary leakage and complying with environmental protection requirements.

[0043] Specifically, Figures 1 to 4As shown, the gas collecting pipe 3 includes: a first gas collecting branch 31, a second gas collecting branch 32 and a gas collecting main 33. The first end of the first gas collecting branch 31 is connected to the first end of the second branch 13, and the first end of the second gas collecting branch 32 is connected to the second end of the connecting pipeline 15; the second end of the first gas collecting branch 31 and the second end of the second gas collecting branch 32 are both connected to the gas collecting main 33 in a switchable manner; wherein the first gas collecting branch 31 and the second gas collecting branch 32 are arranged in parallel. With such a structural arrangement, the parallel configuration of the first gas collecting branch 31 and the second gas collecting branch 32 enables the system to effectively collect refrigerant from multiple sources (such as the second branch 13 and the connecting pipeline 15) at the same time, and can also distribute the refrigerant to different branches, thereby improving the collection efficiency and enhancing the flexibility of the system. Due to the parallel structure, the refrigerant can flow through multiple paths, which helps to reduce the overall flow resistance and improve the working efficiency and response time of the system. In addition, under different environmental conditions or operating modes, the switch status of the branch can be adjusted at any time as needed to ensure that the system can operate effectively under various working conditions.

[0044] Further, the first end of the second branch 13 is connected to the gas collecting main line 33 through the first gas collecting branch 31. The second end of the connecting pipeline 15 is connected to the gas collecting main line 33 through the second gas collecting branch 32.

[0045] Specifically, Figure 4 As shown, the heat exchanger control system also includes: a second control valve 4, which is arranged on the first gas collecting branch 31, and the second control valve 4 is used to control the on-off of the first gas collecting branch 31 and the gas collecting main road 33; the control structure is connected to the second control valve 4, and the control structure is used to control the on-off of the second control valve 4; wherein, when the control structure controls the flow path structure 1 to switch to the direct flow path, the control structure controls the second control valve 4 to open; when the control structure controls the flow path structure 1 to switch to the branch flow path, the control structure controls the second control valve 4 to close. With such a structural setting, the first gas collecting branch 31 and the gas collecting main road 33 can be connected and disconnected by setting the second control valve 4, and the second control valve 4 can make the heat exchanger flexibly switch between the direct flow path and the branch flow path, and can quickly adjust the on-off of the airflow as needed, thereby providing flexibility and adaptability for the system. When the flow path is switched to the direct flow path, opening the second control valve 4 can improve the flow efficiency of the refrigerant, improve the overall energy efficiency of the system, and ensure the best cooling or heating effects.

[0046] Specifically, Figure 4As shown, the heat exchanger control system also includes: a third control valve 5, which is arranged on the second gas collecting branch 32; the third control valve 5 is used to control the on-off of the second gas collecting branch 32 and the gas collecting main road 33; the control structure is connected to the third control valve 5, and the control structure is used to control the on-off of the third control valve 5; wherein, when the control structure controls the flow path structure 1 to switch to the direct flow path, the control structure controls the third control valve 5 to close; when the control structure controls the flow path structure 1 to switch to the branch flow path, the control structure controls the third control valve 5 to open. With such a structural setting, the second gas collecting branch 32 and the gas collecting main road 33 can be connected and disconnected by setting the third control valve 5, and the third control valve 5 can enable the heat exchanger to switch flexibly between the direct flow path and the branch flow path, and can quickly adjust the on-off of the airflow as needed, thereby providing flexibility and adaptability for the system. When the flow path is switched to the direct flow path, opening the third control valve 5 can improve the flow efficiency of the refrigerant, improve the overall energy efficiency of the system, and ensure the best cooling or heating effects.

[0047] Optionally, when the heat exchange device is an air conditioner, the working principle of forming the flow path structure 1 into a direct flow path and a branch flow path and the optimization strategy of the flow path design are: The difference between the direct flow path and the branch flow path mainly stems from the effect of the refrigerant state and the flow path design on the heat transfer efficiency. By designing the heat exchanger in the air conditioner (the heat exchanger of the indoor unit) as a variable flow path, the system can switch between the direct flow path and the branch flow path, thereby optimizing the heat exchange capacity and energy efficiency of the air conditioner under different air volume and refrigerant flow conditions. For example, under high air volume and high flow conditions, a branch flow path with one inlet and two outlets per branch can be used; while under low air volume and low flow conditions, a direct flow path with one inlet and one outlet per branch is used.

[0048] Specifically, when the dryness is low, the branch flow path improves the heat exchange efficiency by increasing the mass flow rate of the refrigerant. However, under high dryness conditions, the high gas flow rate will lead to an increase in pressure drop, thereby reducing system performance. At this time, increasing the flow path to disperse the flow can reduce the pressure drop and optimize energy efficiency. On the contrary, the direct flow path can maintain a higher flow rate under low flow conditions, ensuring a good heat exchange effect, and is suitable for scenarios with low air volume and low flow. In addition, in the heating mode, due to the high pressure in the pipe, the volume flow rate of the refrigerant is small, and it is not suitable for too many branches, which also makes the direct flow path more suitable for this condition.

[0049] And the simulation results show that, in the refrigeration mode, the heat transfer capacity of the branched flow path is 8% higher than that of the straight flow path under high air volume and high flow rate conditions; while in the low air volume and low flow rate conditions, the heat transfer capacity of the straight flow path is 3.5% higher than that of the branched flow path. In the heating mode, the heat transfer capacity of the straight flow path is 5% higher than that of the branched flow path. This indicates that the branched flow path is suitable for high flow rate conditions in refrigeration, while the straight flow path is more suitable for low flow rate conditions in refrigeration and heating conditions. By automatically switching the flow path according to the changes in the operating mode and refrigerant flow rate during actual operation, the heat exchanger can be matched to the optimal flow path in various scenarios, significantly improving the overall energy efficiency of the system.

[0050] Among them, the quality x is an important state parameter of the refrigerant in the pipe, which refers to the proportion of the mass of steam in the refrigerant per unit mass to the total mass. When x = 0, it means that the refrigerant is completely in the liquid state. When x = 1, it means that the refrigerant is completely in the gaseous state. When 0 < x < 1, it means that the refrigerant is in a two-phase state, that is, a gas-liquid mixed state.

[0051] In the heat exchanger, as the refrigerant passes through the heat exchange pipeline, the quality gradually increases from about x = 0.2 at the inlet to x = 1 and finally enters the superheat state. Due to the different qualities, the heat transfer effect between the refrigerant and the copper pipe will also change. In the low-quality state, the heat transfer coefficient inside the pipe is relatively low; as the quality increases, the heat transfer coefficient reaches the highest between about 0.7 and 0.85 of the quality. Specifically, in the front section of the heat exchanger, the quality from 0.2 to 0.5 is regarded as the low quality, while the quality of 0.6 and above with a larger gaseous proportion is regarded as the high quality.

[0052] As can be seen from the above, the straight flow path is suitable for the working conditions of low air volume, low flow rate or heating mode, and the branched flow path is suitable for high air volume and high flow rate.

[0053] For example, when the heat exchange device is an air conditioner, during the operation of the air conditioner, when it is detected that the air conditioner is in a low air volume condition in other modes except the heating mode, the control component controls the flow path structure 1 to switch to the straight flow path. The first control valve 16 is in the closed state, the second control valve 4 is in the open state, and the third control valve 5 is in the closed state. As Figure 2 and Figure 4 shown, after the refrigerant flows out of the liquid separation pipe 2, it will successively enter the heat exchange pipe A and the heat exchange pipe B (i.e., the first branch 12), then enter the heat exchange pipe D and the heat exchange pipe F (i.e., the third branch 14), and then enter the heat exchange pipe E and the heat exchange pipe C (i.e., the second branch 13) from the heat exchange pipe F. Finally, the refrigerant flows from the heat exchange pipe C to the first gas collection branch 31 and the gas collection main path 33.

[0054] When it is detected that the air conditioner is in heating mode, the control component controls the flow path structure 1 to switch to the direct current flow path. The first control valve 16 is in a closed state, the second control valve 4 is in an open state, and the third control valve 5 is in a closed state. Figure 2 and Figure 4 As shown, after the refrigerant flows out from the gas collecting main line 33, it enters the first gas collecting branch 31, and then enters the heat exchange tube C and heat exchange tube E (i.e., the second branch 13) in sequence, and then enters the heat exchange tube F and heat exchange tube D (i.e., the third branch 14) from the heat exchange tube E, and then enters the heat exchange tube B and heat exchange tube A (i.e., the first branch 12) from the heat exchange tube D, and finally, the refrigerant flows from the heat exchange tube A to the liquid separation tube 2.

[0055] As can be seen from the above, the direct current flow path adopts a one-in-one-out design. When the air conditioner is in a low air volume condition or in the heating mode in other modes except the heating mode, the flow rate of the refrigerant is low. If a multi-flow path design is adopted, the flow rate after diversion may be too low, affecting the heat transfer effect. The single flow path design with one inlet and one outlet can ensure that the flow rate of the refrigerant in the entire flow path remains at a high level, thereby improving the boiling heat transfer coefficient or the condensation heat transfer coefficient, and ensuring that a good heat exchange effect can still be achieved under low flow and heating mode conditions.

[0056] Among them, in the heating mode, the refrigerant volume flow rate is small because the pressure in the tube is high.

[0057] When it is detected that the air conditioner is in a high air volume condition in a mode other than the heating mode, the control component controls the flow path structure 1 to switch to the branch flow path. The first control valve 16 is in an open state, the second control valve 4 is in a closed state, and the third control valve 5 is in an open state. Figure 3 and Figure 4 As shown, after the refrigerant flows out from the liquid separator 2, it will enter the heat exchange tube A and the heat exchange tube B (i.e., the first branch 12) in sequence. Then, the refrigerant will flow out from the heat exchange tube B and be divided into two streams. One stream will flow to the heat exchange tube C and the heat exchange tube E (i.e., the second branch 13) in sequence, and the other stream will flow to the heat exchange tube D and the heat exchange tube F (i.e., the third branch 14) in sequence. Then, the refrigerant flowing out of the heat exchange tube E and the refrigerant flowing out of the heat exchange tube F will converge in the connecting pipe 15, and finally flow to the second gas collecting branch 32 and the gas collecting main 33 in sequence through the connecting pipe 15.

[0058] It can be seen that the branch flow path adopts a one-inlet and multiple-outlet design. When the dryness of the refrigerant in the heat exchange tube is low, fewer flow paths make the mass flow rate of the refrigerant in the pipeline larger. At this time, the refrigerant mainly exists in liquid form, so the refrigerant flow resistance is small and the pressure drop increase is not obvious. High flow rate can effectively improve the heat transfer coefficient of flow boiling, thereby improving the heat exchange efficiency. However, when the refrigerant dryness is high, the refrigerant gradually turns into a gaseous state, and the flow rate will increase significantly. Since the friction resistance of the gaseous refrigerant is large when it flows, the high flow rate caused by fewer flow paths will cause a significant pressure drop, affecting the system performance. In this case, increasing the flow path can effectively disperse the flow, thereby reducing the pressure drop and maintaining the stable operation and efficient heat exchange of the system.

[0059] Among them, when the air conditioner is in low air volume mode, the refrigerant flow rate is usually low. This is because the air volume of the air conditioner and the refrigerant flow rate are interrelated. Therefore, when the air conditioner is in high air volume and high flow rate, it can be called that the air conditioner is in high air volume working condition, and when the air conditioner is in low air volume and low flow rate, it can be called that the air conditioner is in low air volume working condition.

[0060] The present invention provides an air conditioner indoor unit, comprising: a heat exchanger control system, wherein the heat exchanger control system is the heat exchanger control system of the above embodiment. With such a structural setting, the heat exchanger control system is provided in the air conditioner indoor unit, which can improve the heat exchange efficiency and overall energy efficiency of the air conditioner indoor unit, so that the air conditioner indoor unit can adapt to different working conditions and environments, thereby improving the heat exchange performance of the air conditioner indoor unit under various working conditions and improving the user experience. The beneficial effects of the heat exchanger control system are the same as those of the heat exchanger control system of the above embodiment, and will not be repeated here.

[0061] The present invention provides an air conditioner, comprising: an air conditioner indoor unit, the air conditioner indoor unit is the air conditioner indoor unit of the above embodiment. The air conditioner of the present invention has the same beneficial effects as the air conditioner indoor unit of the above embodiment, which will not be described in detail here.

[0062] The present invention provides a control method, which is applied to the heat exchanger control system of the above embodiment, and the control method includes: S11, obtaining the operation mode of the heat exchange device.

[0063] S12, controlling the flow path structure 1 to switch to a direct flow path or a branch flow path according to the current operation mode of the heat exchange device.

[0064] Among them, the direct current flow path forms a single flow path for the refrigerant to circulate; the branch flow path forms at least two parallel flow paths for the refrigerant to circulate. By adopting such a control method, the flow path structure 1 can be automatically controlled to switch to the direct current flow path or the branch flow path according to the current operation mode of the heat exchange device, and the heat exchanger can automatically select the optimal flow path according to the actual operating conditions, so that the heat exchanger can provide the best heat exchange performance under various environmental conditions, minimize pressure loss, and avoid the problems of high energy consumption and insufficient comfort caused by the traditional single design. And by accurately controlling the heat exchange process, the system can provide a stable and comfortable indoor environment regardless of high load or low load. At the same time, the optimized flow path design and control can also reduce equipment wear caused by excessive pressure and insufficient heat exchange, reduce the occurrence rate of failures and extend the service life of the equipment. In addition, while improving energy utilization and reducing energy consumption, the system can also reduce greenhouse gas emissions, which is in line with the trend of green environmental protection and has significant economic and environmental protection value. The control method of the present invention can effectively solve the technical problem that the flow path design of the indoor unit heat exchanger in the variable frequency air conditioner in the prior art cannot achieve a balance between efficient heat exchange and system pressure drop, resulting in the variable frequency air conditioner being difficult to simultaneously take into account high efficiency and comfort under different working conditions.

[0065] Specifically, the method of controlling the flow path structure 1 to switch to a direct flow path or a branch flow path according to the current operation mode of the heat exchange device includes: if the heat exchange device is in a heating mode, the flow path structure 1 is controlled to switch to a direct flow path; if the heat exchange device is in a cooling mode or other modes, the current refrigerant flow m3 is calculated; and according to the current refrigerant flow m3, the flow path structure 1 is controlled to switch to a direct flow path or a branch flow path. With such a control method, since the internal pressure of each heat exchange tube 11 in the flow path structure 1 is high when the heat exchange device is in a heating mode, the refrigerant volume flow rate is small, and then by controlling the flow path structure 1 to switch to a direct flow path or a branch flow path, it can ensure that the flow rate of the refrigerant in the entire flow path is maintained at a high level, thereby improving the boiling heat transfer coefficient or the condensation heat transfer coefficient, and ensuring that a good heat exchange effect can still be achieved under the heating mode. In addition, when the heat exchange device is in a cooling mode or other modes, according to the current refrigerant flow m3, the flow path structure 1 is controlled to switch to a direct flow path or a branch flow path. This design enables the heat exchanger to automatically select the optimal flow path under various working conditions, thereby significantly improving the heat exchange efficiency and overall energy efficiency of the system. This control method effectively solves the limitation that traditional heat exchangers cannot take into account multiple working conditions, and improves the flexibility and adaptability of the system. By adjusting the flow path structure in real time, the heat exchanger can achieve the optimal heat exchange performance under different load and environmental conditions, ensuring efficient operation and energy saving of the equipment.

[0066] Among them, other modes refer to modes such as dehumidification mode.

[0067] Specifically, the method of controlling the flow path structure 1 to switch to a direct flow path or a branch flow path according to the current refrigerant flow m3 includes: if the current refrigerant flow m3 is greater than or equal to the first preset threshold m1, the flow path structure 1 is controlled to switch to the branch flow path; if the current refrigerant flow m3 is less than or equal to the second preset threshold m2, the flow path structure 1 is controlled to switch to the direct flow path; if the current refrigerant flow m3 is less than the first preset threshold m1 and greater than the second preset threshold m2, the flow path structure 1 is controlled to maintain the direct flow path or the branch flow path; wherein, m1>m2. By adopting such a control method, the system can automatically select the optimal flow path according to the flow change, ensuring the optimal operating state of the heat exchanger under different working conditions. Through precise flow control, the heat exchange efficiency and the overall system energy efficiency are improved to adapt to different working conditions. The flexibility and adaptability of the heat exchanger are enhanced.

[0068] Optionally, if the current refrigerant flow rate m3 is less than or equal to the second preset threshold value m2, it indicates that the heat exchange device is in a low flow condition. If the current refrigerant flow rate m3 is greater than or equal to the first preset threshold value m1, it indicates that the heat exchange device is in a high air volume condition. If the current refrigerant flow rate m3 is less than the first preset threshold value m1 and greater than the second preset threshold value m2, the flow path mode of the flow path structure 1 is maintained without change.

[0069] The first preset threshold m1 is used to control the upper limit of the flow path switching, and the second preset threshold m2 is used to control the lower limit of the flow path switching.

[0070] Optionally, the first preset threshold m1 is a high flow threshold m1; the second preset threshold m2 is a low flow threshold m2; the first preset threshold m1 and the second preset threshold m2 are determined by the following method: During the design phase, the mass flow rate m0 is first determined experimentally. The mass flow rate m0 is the flow point where the effects of the direct flow path and the branch flow path are basically equivalent.

[0071] Then, the first preset threshold m1 and the second preset threshold m2 are set according to the mass flow m0: m1=x1*m0 (1<x1<1.5, 1.1 is optional), m2=x2*m0 (0.7<x2<1, 0.9 is optional). Setting the first preset threshold m1 and the second preset threshold m2 in this way can avoid the problem of frequent flow path switching when the mass flow m0 is near, and enhance the stability of the system.

[0072] Among them, x1 refers to the coefficient used to determine the first preset threshold m1; x2 refers to the coefficient used to determine the second preset threshold m2. x1 is preferably 1.1 and x2 is preferably 0.9, in order to be close to 1, so that it is easier to trigger the switching condition when the mass flow rate is near m0, otherwise it is not easy to trigger the flow path switching.

[0073] The mass flow rate m0 can be understood as when the refrigerant flow rate is m0, the heat exchange capacity of the direct flow path and the branch flow path is close. The mass flow rate m0 is determined by experiment, reflecting the similarity of the heat exchange efficiency of the two flow path structures under this flow rate.

[0074] Specifically, the heat exchange device includes a compressor; if the heat exchange device is in a cooling mode or other modes, the method for calculating the current refrigerant flow rate m3 includes: obtaining the operating frequency f, the compressor displacement Vd and the volumetric efficiency η, and the refrigerant specific volume ν at the suction port of the compressor; calculating the current refrigerant flow rate m3 by the obtained operating frequency f, the compressor displacement Vd, the volumetric efficiency η and the refrigerant specific volume ν; the calculation formula is: .

[0075] Furthermore, the volumetric efficiency η is related to the operating frequency f of the compressor. The change of the volumetric efficiency η can be mainly determined by the operating frequency f of the compressor. This relationship is based on experimental results, which means that the volumetric efficiency of the compressor at different operating frequencies has been measured in the development or testing stage to find its corresponding relationship. Then, the volumetric efficiency η corresponding to the operating frequency f of the compressor can be obtained by obtaining the operating frequency f of the compressor.

[0076] Furthermore, the compressor displacement Vd is a fixed value or a set value. When the compressor is a non-variable capacity compressor, the compressor displacement Vd corresponds to the compressor model, and each model has a fixed compressor displacement Vd. When the compressor is a variable capacity compressor, the compressor displacement Vd is set according to actual conditions.

[0077] Furthermore, the refrigerant specific volume ν is the inverse of the refrigerant density p, that is, The refrigerant density p can be determined by the suction pressure of the compressor and the suction temperature of the compressor. Specifically, the corresponding refrigerant density p is found by the suction pressure of the compressor and the suction temperature of the compressor.

[0078] Furthermore, the suction pressure of the compressor and the suction temperature of the compressor are directly measured.

[0079] Optionally, when the heat exchange device is an air conditioner, the control method of the heat exchanger is: Step 1: Get the operating mode of the air conditioner.

[0080] Step 2: If the air conditioner is currently in heating mode, the control component controls the flow path structure 1 to switch to a direct current flow path. The first control valve 16 is in a closed state, the second control valve 4 is in an open state, and the third control valve 5 is in a closed state. Figure 2 and Figure 4As shown, after the refrigerant flows out from the gas collecting main line 33, it enters the first gas collecting branch 31, and then enters the heat exchange tube C and heat exchange tube E (i.e., the second branch 13) in sequence, and then enters the heat exchange tube F and heat exchange tube D (i.e., the third branch 14) from the heat exchange tube E, and then enters the heat exchange tube B and heat exchange tube A (i.e., the first branch 12) from the heat exchange tube D, and finally, the refrigerant flows from the heat exchange tube A to the liquid separation tube 2.

[0081] Step 3: If the current air conditioner is in cooling mode or dehumidification mode, calculate the formula , calculate the current refrigerant flow m3. According to the current refrigerant flow m3, the flow path structure 1 is controlled to switch to a direct flow path or a branch flow path.

[0082] Step 4: The current refrigerant flow rate m3 is greater than or equal to the first preset threshold m1. At this time, the air conditioner is in a high air volume condition. The control structure controls the flow path structure 1 to switch to the branch flow path. The first control valve 16 is in an open state, the second control valve 4 is in a closed state, and the third control valve 5 is in an open state. Figure 3 and Figure 4 As shown, after the refrigerant flows out from the liquid separator 2, it will enter the heat exchange tube A and the heat exchange tube B (i.e., the first branch 12) in sequence. Then, the refrigerant will flow out from the heat exchange tube B and be divided into two streams. One stream will flow to the heat exchange tube C and the heat exchange tube E (i.e., the second branch 13) in sequence, and the other stream will flow to the heat exchange tube D and the heat exchange tube F (i.e., the third branch 14) in sequence. Then, the refrigerant flowing out of the heat exchange tube E and the refrigerant flowing out of the heat exchange tube F will converge in the connecting pipe 15, and finally flow to the second gas collecting branch 32 and the gas collecting main 33 in sequence through the connecting pipe 15.

[0083] Step 5: If the current refrigerant flow rate m3 is less than or equal to the second preset threshold value m2, the air conditioner is in a low air volume condition, the control structure controls the flow path structure 1 to switch to a direct flow path, the first control valve 16 is in a closed state, the second control valve 4 is in an open state, and the third control valve 5 is in a closed state. Figure 2 and Figure 4 As shown, after the refrigerant flows out from the liquid distributor 2, it will enter the heat exchange tube A and the heat exchange tube B (i.e., the first branch 12) in sequence, and then enter the heat exchange tube D and the heat exchange tube F (i.e., the third branch 14), and then enter the heat exchange tube E and the heat exchange tube C (i.e., the second branch 13) from the heat exchange tube F, and finally the refrigerant flows from the heat exchange tube C to the first gas collecting branch 31 and the gas collecting main 33.

[0084] Step 6, if the current refrigerant flow m3 is less than the first preset threshold m1 and greater than the second preset threshold m2, regardless of whether the current flow path structure 1 is in a direct flow path or a branch flow path, the control structure controls the flow path structure 1 to maintain the current flow path mode without switching.

[0085] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable when appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0086] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, and this embodiment will not be described in detail here.

[0087] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0088] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0089] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A heat exchanger control system, characterized in that: The heat exchanger control system is arranged on the heat exchange device, and the heat exchanger control system comprises: A flow path structure (1), the flow path structure (1) having a plurality of heat exchange tubes (11), the plurality of heat exchange tubes (11) forming a straight flow path or a branch flow path for circulating a refrigerant; A control structure connected to the flow path structure (1); the control structure is used to control the flow path structure (1) to switch to the direct flow path or the branch flow path; When the control structure controls the flow path structure (1) to switch to the direct flow path, the plurality of heat exchange tubes (11) are connected in sequence to form a single flow path for the refrigerant to flow; when the control structure controls the flow path structure (1) to switch to the branch flow path, at least two of the plurality of heat exchange tubes (11) are divided into at least two parallel branches to form at least two flow paths for the refrigerant to flow.

2. The heat exchanger control system according to claim 1, characterized in that: The heat exchanger control system further comprises: a liquid distributing pipe (2), the liquid distributing pipe (2) being connected to an input portion of the flow path structure (1), the refrigerant flowing into the flow path structure (1) through the liquid distributing pipe (2); or the refrigerant flowing into the liquid distributing pipe (2) through the flow path structure (1); an air collecting pipe (3), the air collecting pipe (3) being respectively connected to the output part of the flow path structure (1), the air collecting pipe (3) being used to collect the refrigerant flowing out of the flow path structure (1); or the air collecting pipe (3) being used to transport the refrigerant into the flow path structure (1); The output portion of the flow path structure (1) comprises a first output end and a second output end, and the first output end of the flow path structure (1) and the second output end of the flow path structure (1) are both connected to the gas collecting pipe (3) in a switchable manner; when the control structure controls the flow path structure (1) to switch to the direct flow path, the first output end of the flow path structure (1) and the gas collecting pipe (3) are in a connected state, and the second output end of the flow path structure (1) and the gas collecting pipe (3) are in a disconnected state; when the control structure controls the flow path structure (1) to switch to the branch flow path, the first output end of the flow path structure (1) and the gas collecting pipe (3) are in a disconnected state, and the second output end of the flow path structure (1) and the gas collecting pipe (3) are in a connected state.

3. The heat exchanger control system according to claim 2, characterized in that: The plurality of heat exchange tubes (11) form a first branch (12), a second branch (13) and a third branch (14); the first end of the first branch (12) forms an input portion of the flow path structure (1); the second end of the first branch (12) is connected to the first end of the second branch (13) in an on-off manner, and the first end of the second branch (13) is connected to the gas collecting pipe (3) in an on-off manner; the second end of the second branch (13) is connected to the second end of the third branch (14); and the first end of the third branch (14) is connected to the second end of the first branch (12); When the control structure controls the flow path structure (1) to switch to the direct current flow path, the first end of the second branch (13) and the second end of the first branch (12) are in a disconnected state; and the first end of the second branch (13) and the gas collecting pipe (3) are in a connected state.

4. The heat exchanger control system according to claim 3, characterized in that: The flow path structure (1) further comprises: a connecting pipe (15), wherein a first end of the connecting pipe (15) is respectively connected to a second end of the second branch (13) and a second end of the third branch (14); and a second end of the connecting pipe (15) forms a second output end of the flow path structure (1); When the control structure controls the flow path structure (1) to switch to the branch flow path, the first end of the second branch path (13) is in a connected state with the second end of the first branch path (12); the first end of the second branch path (13) is in a disconnected state with the gas collecting pipe (3); and the second end of the connecting pipe (15) is in a connected state with the gas collecting pipe (3).

5. The heat exchanger control system according to claim 3, characterized in that: The flow path structure (1) further comprises: a first control valve (16), the first control valve (16) being arranged between the second end of the first branch (12) and the first end of the second branch (13), and the first control valve (16) being connected to the second end of the first branch (12) and the first end of the second branch (13) respectively; the first control valve (16) being used to control the on-off between the second end of the first branch (12) and the first end of the second branch (13); the control structure being connected to the first control valve (16), and being used to control the opening and closing of the first control valve (16); When the control structure controls the flow path structure (1) to switch to the branch flow path, the control structure controls the first control valve (16) to open; when the control structure controls the flow path structure (1) to switch to the direct flow path, the control structure controls the first control valve (16) to close.

6. The heat exchanger control system according to claim 4, characterized in that: The gas collecting pipe (3) comprises: a first gas collecting branch (31) and a second gas collecting branch (32), wherein a first end of the first gas collecting branch (31) is connected to a first end of the second branch (13), and a first end of the second gas collecting branch (32) is connected to a second end of the connecting pipeline (15); A gas collecting main circuit (33), wherein the second end of the first gas collecting branch circuit (31) and the second end of the second gas collecting branch circuit (32) are both connected to the gas collecting main circuit (33) in a disconnectable manner; Wherein, the first gas collecting branch (31) and the second gas collecting branch (32) are arranged in parallel.

7. The heat exchanger control system according to claim 6, characterized in that: The heat exchanger control system further comprises: a second control valve (4), the second control valve (4) being arranged on the first gas collecting branch line (31), the second control valve (4) being used to control the on-off of the first gas collecting branch line (31) and the gas collecting main line (33); the control structure being connected to the second control valve (4), the control structure being used to control the on-off of the second control valve (4); When the control structure controls the flow path structure (1) to switch to the direct flow path, the control structure controls the second control valve (4) to open; when the control structure controls the flow path structure (1) to switch to the branch flow path, the control structure controls the second control valve (4) to close.

8. The heat exchanger control system according to claim 6, characterized in that: The heat exchanger control system further comprises: a third control valve (5), the third control valve (5) being arranged on the second gas collecting branch line (32); the third control valve (5) being used for controlling the on-off of the second gas collecting branch line (32) and the gas collecting main line (33); the control structure being connected to the third control valve (5), the control structure being used for controlling the on-off of the third control valve (5); When the control structure controls the flow path structure (1) to switch to the direct flow path, the control structure controls the third control valve (5) to close; when the control structure controls the flow path structure (1) to switch to the branch flow path, the control structure controls the third control valve (5) to open.

9. An air conditioner indoor unit, characterized in that: include: A heat exchanger control system, wherein the heat exchanger control system is the heat exchanger control system according to any one of claims 1 to 8.

10. An air conditioner, characterized in that: include: An air-conditioning indoor unit, wherein the air-conditioning indoor unit is the air-conditioning indoor unit according to claim 9.

11. A control method, characterized in that: The control method is applied to the heat exchanger control system according to any one of claims 1 to 8, and the control method comprises: Get the operation mode of the heat exchange device; According to the current operation mode of the heat exchange device, the flow path structure (1) is controlled to switch to a direct flow path or a branch flow path; The direct flow path forms a single flow path for the refrigerant to flow; and the branch flow paths form at least two parallel flow paths for the refrigerant to flow.

12. The control method according to claim 11, characterized in that: The method of controlling the flow path structure (1) to switch to a direct flow path or a branch flow path according to the current operation mode of the heat exchange device comprises: If the heat exchange device is in a heating mode, controlling the flow path structure (1) to switch to the direct flow path; If the heat exchange device is in cooling mode or other mode, calculate the current refrigerant flow m3; According to the current refrigerant flow rate m3, the flow path structure (1) is controlled to switch to the direct flow path or the branch flow path.

13. The control method according to claim 12, characterized in that: The method of controlling the flow path structure (1) to switch to the direct flow path or the branch flow path according to the current refrigerant flow rate m3 comprises: If the current refrigerant flow rate m3 is greater than or equal to the first preset threshold m1, the flow path structure (1) is controlled to switch to the branch flow path; If the current refrigerant flow rate m3 is less than or equal to the second preset threshold value m2, the flow path structure (1) is controlled to switch to the direct flow path; If the current refrigerant flow rate m3 is less than the first preset threshold value m1 and greater than the second preset threshold value m2, the flow path structure (1) is controlled to be maintained in the direct flow path or the branch flow path; Among them, m1>m2.

14. The control method according to claim 13, characterized in that: The heat exchange device includes a compressor; if the heat exchange device is in a cooling mode or other mode, the method for calculating the current refrigerant flow m3 includes: Obtaining the operating frequency f, the compressor displacement Vd and the volumetric efficiency η of the compressor, and the refrigerant specific volume ν at the suction port of the compressor; The current refrigerant flow m3 is calculated by obtaining the operating frequency f, compressor displacement Vd, volumetric efficiency η and refrigerant specific volume ν; the calculation formula is: .

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