Gas-liquid separator, heat pump system and control method

Abstract

The invention discloses a gas-liquid separator, a heat pump system and a control method, and the gas-liquid separator comprises a tank body, a working medium pipe assembly and a heat exchange assembly; an accommodating cavity is formed in the tank body; the working medium pipe assembly comprises a working medium inlet pipe, a working medium outlet pipe and a high-pressure air pipe which are arranged on the tank body at intervals, one part of the working medium inlet pipe is located outside the tank body, the other part of the working medium inlet pipe is located in the containing cavity and used for communicating with the containing cavity, and one part of the working medium outlet pipe is located outside the tank body, and the other part of the working medium outlet pipe is located in the containing cavity and used for communicating with the containing cavity. The high-pressure air pipe penetrates through the tank body, and the two ends are located outside the tank body; the heat exchange assembly is arranged in the containing cavity and arranged on the pipe section, located in the containing cavity, of the high-pressure air pipe. According to the technical scheme, efficient heat exchange of the gas-liquid separator can be achieved.

Description

Technical Field

[0001] The present application relates to the technical field of HVAC systems, and in particular to a gas-liquid separator, a heat pump system and a control method. Background Art

[0002] Heat pump technology is an energy-saving technology that can efficiently utilize low-grade energy. It has broad application prospects in building heating, industrial waste heat utilization, new energy and other fields.

[0003] In the related art, when the compressor of the heat pump system is in the working cycle, it is easy for a large amount of liquid refrigerant to enter the compressor, causing liquid hammer, affecting the normal operation of the compressor, and even causing a working failure. To avoid this phenomenon, a gas-liquid separator is usually provided to separate the liquid and gaseous refrigerants to prevent the liquid refrigerant from entering the compressor. However, under low temperature conditions, the evaporator is prone to frost, and the outdoor unit needs to defrost the evaporator in defrosting mode to ensure the operating efficiency of the unit. At this time, the gas-liquid separator has low heat exchange efficiency, and excessive accumulation of liquid refrigerant inside will also cause "liquid hammer" in the compressor, reducing the operating stability of the system. Summary of the invention

[0004] The embodiments of the present application provide a gas-liquid separator, a heat pump system and a control method, which can achieve efficient heat exchange of the gas-liquid separator.

[0005] In the first aspect, an embodiment of the present application provides a gas-liquid separator, which includes a tank body, a working fluid pipe assembly and a heat exchange assembly; a accommodating cavity is formed in the tank body; the working fluid pipe assembly includes a working fluid inlet pipe, a working fluid outlet pipe and a high-pressure air pipe which are arranged on the tank body at intervals, a part of the working fluid inlet pipe is located outside the tank body, and the other part is located inside the accommodating cavity and is used to connect with the accommodating cavity, a part of the working fluid outlet pipe is located outside the tank body, and the other part is located inside the accommodating cavity and is used to connect with the accommodating cavity, the high-pressure air pipe is passed through the tank body, and both ends are located outside the tank body; the heat exchange assembly is arranged in the accommodating cavity, and is arranged on the pipe section of the high-pressure air pipe located inside the accommodating cavity.

[0006] In some embodiments, the heat exchange assembly includes a partition and a plurality of heat exchange plates, wherein the partition is disposed in the high-pressure air pipe and partitions the interior of the high-pressure air pipe to form an air inlet pipe section and an air outlet pipe section;

[0007] The heat exchange plate is connected to the outer wall of the high-pressure air pipe, and an air flow passage is arranged inside the heat exchange plate, and the air flow passage communicates the air inlet pipe section and the air outlet pipe section.

[0008] In some embodiments, a plurality of heat exchange plates are provided, and the plurality of heat exchange plates are arranged around the high-pressure air pipe and are radially distributed along the radial direction of the high-pressure air pipe.

[0009] In some embodiments, the air flow channel includes a plurality of air intake microchannels, a collecting channel and a plurality of exhaust microchannels arranged in parallel, the plurality of air intake microchannels connect the air intake pipe section and the collecting channel, and the plurality of exhaust microchannels connect the collecting channel and the air outlet pipe section.

[0010] In some embodiments, the air outlet pipe section passes through the side wall or the bottom wall of the tank body and extends out of the tank body.

[0011] In some embodiments, the working medium inlet pipe has an inlet pipe outlet located in the accommodating cavity, wherein the inlet pipe outlet is located above the heat exchange component.

[0012] In some embodiments, the inlet pipe outlet is arranged toward the inner wall of the tank body.

[0013] In some embodiments, the working medium outlet pipe has an outlet inlet located in the accommodating cavity, and the outlet inlet is adjacent to the top of the tank body and is arranged higher than the inlet outlet.

[0014] In some embodiments, the tank body includes a container body and an upper end cover that are connected to each other, the container body and the upper end cover enclose the accommodating cavity, the working fluid inlet pipe and the working fluid outlet pipe are both fixedly arranged on the upper end cover, and the high-pressure gas pipe is passed through the upper end cover and the container body.

[0015] In a second aspect, an embodiment of the present application provides a heat pump system, the heat pump system comprising an outdoor unit and a hydraulic module connected by pipelines, the outdoor unit comprising a compressor, an air cooler, a regenerator, an evaporator and a gas-liquid separator as described in any one of the above connected by pipelines, the hydraulic module comprising the air cooler;

[0016] The compressor has an exhaust port and an air return port, a first pipeline and a second pipeline are arranged in parallel at the exhaust port of the compressor, the exhaust port is connected to the air inlet of the air cooler through the first pipeline, the exhaust port is connected to the air pipe inlet of the high-pressure air pipe through the second pipeline, the air pipe outlet of the high-pressure air pipe is connected to the air inlet of the air cooler, and the air return port is connected to the outlet of the working medium outlet pipe;

[0017] The air outlet of the air cooler is connected to the first inlet of the regenerator, the first outlet of the regenerator is connected to the air inlet of the evaporator, the air outlet of the evaporator is connected to the second inlet of the regenerator, and the second outlet of the regenerator is connected to the inlet of the working medium inlet pipe of the gas-liquid separator;

[0018] The outdoor unit further comprises a valve assembly and a throttling assembly, wherein the valve assembly comprises a first stop valve, a second stop valve and a defrost bypass valve, the throttling assembly comprises a throttling valve and a defrost capillary tube, the first stop valve is arranged on the first pipeline, the second stop valve is arranged on the second pipeline, and the throttling valve is arranged between the first outlet of the regenerator and the air inlet of the evaporator;

[0019] The outdoor unit further comprises a bypass, wherein the bypass connects the exhaust port of the compressor and the air inlet of the evaporator, and the defrost bypass valve and the defrost capillary tube are arranged in series on the bypass.

[0020] In a third aspect, an embodiment of the present application provides a control method, which is used for the heat pump system as described above, and the steps include:

[0021] S1: Collecting outdoor air temperature t1 and humidity parameters, setting evaporator fin temperatures t3 and t4, and judging whether the evaporator is likely to be frosted based on the collected outdoor air temperature t1 and humidity parameters;

[0022] S2: If there is a possibility of frosting, the evaporator fin temperature t2 is collected, and it is determined whether the evaporator fin temperature t2 is greater than the preset value t3; if there is no possibility of frosting, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to operate the heating mode;

[0023] S3: If the evaporator fin temperature t2 is less than or equal to the preset value t3, the first stop valve is controlled to be closed, and the second stop valve and the defrost bypass valve are controlled to be opened to run the defrost mode; if the evaporator fin temperature t2 is greater than the preset value t3, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to continue running the heating mode;

[0024] In some embodiments, after the defrost mode is run, after a preset time t, the evaporator fin temperature t5 is collected, and it is determined whether the evaporator fin temperature t5 is greater than the preset value t4;

[0025] If the evaporator fin temperature t5 is less than or equal to the preset value t4, the first stop valve is controlled to be closed, and the second stop valve and the defrost bypass valve are controlled to be opened to continue running the defrost mode. If the evaporator fin temperature t5 is greater than the preset value t4, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to run the heating mode.

[0026] Based on the gas-liquid separator of the embodiment of the present application, a containing chamber is formed in the tank body. When the working fluid enters the gas-liquid separator, the liquid is deposited downward and adheres to the inner wall surface of the tank body due to the large effect of gravity, and is stored in the containing chamber to avoid liquid reflux and liquid hammer. A portion of the working fluid inlet pipe is located outside the tank body, and the other portion is located inside the containing chamber and is used to connect to the containing chamber, which is helpful for storing liquid working fluid and separating liquid and gaseous working fluids. A portion of the working fluid outlet pipe is located outside the tank body, and the other portion is located inside the containing chamber and is used to connect to the containing chamber, which is used to continue the working cycle of the gaseous working fluid separated in the gas-liquid separator in the heat pump system.

[0027] The high-pressure gas pipe is installed in the tank body, and both ends are located outside the tank body. High-temperature and high-pressure gaseous working medium is introduced into the high-pressure gas pipe, and heat is exchanged with the low-temperature working medium in the accommodating chamber, so as to convert the liquid working medium into gaseous working medium through high temperature, thereby reducing the risk of "liquid hammer" phenomenon. The heat exchange component is arranged in the accommodating chamber of the tank body, and is arranged on the pipe section of the high-pressure gas pipe located in the accommodating chamber, so as to be in closer contact with the low-temperature and low-pressure working medium in the accommodating chamber, thereby reducing the distance of heat transfer and heat loss, thereby directly exchanging heat on the high and low pressure sides inside the tank body, evaporating the liquid working medium inside the tank body, reducing the storage of liquid working medium in the tank body, having high heat exchange efficiency, avoiding liquid hammer, enhancing system reliability, and thus improving heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0029] Figure 1 This is a schematic structural diagram of an embodiment of a heat pump system of the present application;

[0030] Figure 2 for Figure 1 A schematic diagram of the structure of the heating mode of the heat pump system shown in FIG.

[0031] Figure 3 for Figure 1A schematic diagram of the structure of the defrost mode of the heat pump system shown in;

[0032] Figure 4 for Figure 1 A schematic diagram of the structure of a gas-liquid separator of a heat pump system shown in FIG.

[0033] Figure 5 for Figure 4 A schematic diagram of the structure of the gas-liquid separator from a top view shown in FIG.

[0034] Figure 6 for Figure 4 Schematic diagram of the flow path after the high-pressure gas pipe and heat exchange component of the gas-liquid separator are assembled;

[0035] Figure 7 for Figure 4 Schematic diagram of the assembly structure of the working fluid inlet pipe and the working fluid outlet pipe of the gas-liquid separator shown in FIG.

[0036] Figure 8 This is a flow chart of an embodiment of a heat pump system control method of the present application.

[0037] Description of Figure Numbers:

[0038] 1. Heat pump system; 10. Outdoor unit; 100. Gas-liquid separator; 110. Tank; 111. Accommodating chamber; 112. Container body; 113. Upper end cover; 114. Lower end cover; 115. Support assembly; 120. Working fluid pipe assembly; 121. Working fluid inlet pipe; 1211. Inlet pipe outlet; 1212. Inlet pipe inlet; 122. Working fluid outlet pipe; 1221. First part; 1221a. Outlet pipe outlet; 1222. Second part; 1222a. Outlet pipe inlet; 1222b. Vertical part; 1222c. Bend part; 1223. Oil return hole; 123. High-pressure gas pipe; 1231. Inlet pipe section; 1232. Outlet pipe section; 1233. Gas pipe inlet; 1234. Gas Pipe outlet; 130, heat exchange component; 131, partition; 132, heat exchange plate; 133, air flow channel; 1331, air inlet microchannel; 1332, collecting channel; 1333, exhaust microchannel; 200, compressor; 210, exhaust port; 220, return air port; 300, air cooler; 400, regenerator; 410, first inlet; 420, first outlet; 430, second inlet; 440, second outlet; 500, evaporator; 600, valve assembly; 610, first stop valve; 620, second stop valve; 630, defrost bypass valve; 700, throttling assembly; 710, throttling valve; 720, defrost capillary; 800, bypass; 900, fan; 20, hydraulic module.

[0039] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present application clearer, the following part will further describe the embodiments of the present application in detail in conjunction with the accompanying drawings.

[0041] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0042] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0044] Heat pump technology is an energy-saving technology that can efficiently utilize low-grade energy. As an environmentally friendly and efficient energy conversion device, it has attracted much attention and has great development potential. It has broad application prospects in the fields of building heating, industrial waste heat utilization, new energy, etc. Traditional heat pump water heaters use refrigerants such as HCFCs, which are not only harmful to the atmospheric ozone layer, but also aggravate the greenhouse effect, posing a serious threat to the environment.

[0045] CO2 itself is an environmentally friendly natural refrigerant with good physical and chemical properties and excellent heating performance. Especially at low temperatures, CO2 has good thermal properties and is very suitable as a working fluid for transcritical cycles. It has shown great advantages in the field of heat pump technology. The air source CO2 heat pump system is green, environmentally friendly, energy-saving and has a wide range of applications. It can provide hot water from 60°C to 90°C in a wide range of ambient temperatures. It has a wide range of applications, especially being able to solve the problem of hot water supply under low ambient temperature conditions.

[0046] In the related art, during the working cycle, the compressor of the outdoor unit of the air source CO2 heat pump system is prone to the phenomenon that liquid refrigerant lubricating oil is sucked into the compressor cylinder along with the gaseous refrigerant, damaging the suction valve plate. This phenomenon is usually called liquid hammer. "Liquid hammer" can affect the normal operation of the compressor and even cause working failures. In order to avoid "liquid hammer", a gas-liquid separator is usually provided in the outdoor unit of the heat pump system to separate the liquid and gaseous refrigerants and prevent the liquid refrigerant from entering the compressor.

[0047] In the heating mode, the evaporator of the outdoor unit absorbs heat from the ambient air to evaporate the heat transfer medium. After the working medium vapor is compressed by the compressor, its pressure and temperature rise. The high-temperature vapor transfers heat to the hydraulic module through the pipeline, thereby heating the water in the water tank in the hydraulic module. When the outdoor temperature is low, the surface temperature of the evaporator fins is lower than the dew point temperature of the ambient air. The water vapor in the air will solidify into liquid on its surface and adhere to it, thus forming a frost layer, resulting in reduced gas flow and weakened evaporator heat transfer performance. At this time, the outdoor unit needs to run the defrost mode to defrost the surface of the evaporator fins, thereby ensuring the operating efficiency of the outdoor unit. However, at this time, due to the low heat exchange efficiency of the gas-liquid separator, the accumulation of too much liquid refrigerant inside it will cause "liquid hammer" in the compressor, reducing the stability of system operation.

[0048] To solve the above problems, please refer to Figures 1 to 3 The present application proposes a heat pump system 1. In the embodiment of the present application, the heat pump system 1 includes an outdoor unit 10 and a hydraulic module connected by pipelines. The hydraulic module includes an air cooler 300 and a water tank connected to the air cooler 300, etc., for providing hot water to the user end. In addition, the heat pump system 1 also includes an electric control system for controlling the outdoor unit 10 and the hydraulic module. The electric control system can receive user instructions and adjust the operating speed, working mode, etc. of the indoor unit and the hydraulic module. The working mode of the outdoor unit 10 may include a heating mode and a defrosting mode.

[0049] The outdoor unit 10 may include a casing, and a compressor 200, an air cooler 300, a regenerator 400, an evaporator 500, and a gas-liquid separator 100 disposed in the casing and connected by pipelines, wherein the compressor 200 is a core component of the outdoor unit 10, responsible for compressing the working medium and delivering it to the outdoor unit 10. The outdoor unit 10 also includes a valve assembly 600 and a throttling assembly 700, and the valve assembly 600 is controlled by an electronic control system to realize the switching of the heating mode and the defrosting mode of the heat pump system 1.

[0050] In addition, the outdoor unit 10 also includes a fan 900, which is arranged adjacent to the evaporator 500 and can draw air from the outdoor environment and force the air to pass through the evaporator 500 to enable heat exchange between the working fluid in the evaporator 500 and the air, thereby improving the heat exchange efficiency of the evaporator 500.

[0051] In some embodiments, the gas-liquid separator 100 is mainly used to protect the compressor 200 from damage by the liquid working medium. Figures 3 to 5 The gas-liquid separator 100 includes a tank body 110, a working fluid pipe assembly 120 and a heat exchange assembly 130. A receiving chamber 111 is formed in the tank body 110. The working fluid (usually a gas containing a small amount of liquid, in the air source CO2 heat pump system, the working fluid is CO2) transmitted by the evaporator 500 enters the gas-liquid separator 100. Due to the greater effect of gravity, the liquid is deposited downward and attached to the inner wall surface of the tank body 110 and is stored in the receiving chamber 111, while the gas continues to flow in the receiving chamber 111 and is then sucked in and compressed by the compressor 200.

[0052] The working fluid pipe assembly 120 includes a working fluid inlet pipe 121, a working fluid outlet pipe 122 and a high-pressure gas pipe 123 which are spaced apart from each other on the tank body 110. A portion of the working fluid inlet pipe 121 is located outside the tank body 110 and is used to connect to the regenerator 400, and another portion is located in the accommodating cavity 111 and is used to connect to the accommodating cavity 111, so as to introduce the working fluid in the regenerator 400 into the accommodating cavity 111 of the gas-liquid separator 100, which helps to store the liquid working fluid and separate the liquid and gaseous working fluids.

[0053] A portion of the working medium outlet pipe 122 is located outside the tank body 110 and is used to connect to the compressor 200, and another portion is located inside the accommodating chamber 111 and is used to connect to the accommodating chamber 111, so as to introduce the gaseous working medium separated in the gas-liquid separator 100 into the compressor 200 to continue the working cycle.

[0054] The high-pressure gas pipe 123 is arranged through the tank body 110, and both ends are located outside the tank body 110, one end is used to connect to the compressor 200, and the other end is used to connect to the air cooler 300. The high-temperature and high-pressure gaseous working medium discharged by the compressor 200 is introduced into the high-pressure gas pipe 123, and heat is exchanged with the low-temperature working medium in the accommodating chamber 111, so as to convert the liquid working medium into the gaseous working medium through high temperature, thereby reducing the risk of "liquid hammer" phenomenon.

[0055] The heat exchange component 130 is arranged in the accommodating chamber 111 of the tank body 110, and is arranged on the pipe section of the high-pressure gas pipe 123 located in the accommodating chamber 111. It can be in closer contact with the low-temperature and low-pressure working medium in the accommodating chamber 111, reducing the distance of heat transfer and reducing heat loss, so as to directly perform heat exchange on the high and low pressure sides inside the tank body 110, evaporate the liquid working medium inside the tank body 110, reduce the storage of liquid working medium in the tank body 110, have high heat exchange efficiency, avoid liquid hammer of the compressor 200, enhance system reliability, and thus improve heat exchange efficiency.

[0056] Specifically, the compressor 200 has an exhaust port 210 and an air return port 220, a first pipeline and a second pipeline are arranged in parallel at the exhaust port 210 of the compressor 200, the exhaust port 210 is connected to the air inlet of the air cooler 300 through the first pipeline, the exhaust port 210 is connected to the air pipe inlet 1233 of the high-pressure air pipe 123 through the second pipeline, the air pipe outlet 1234 of the high-pressure air pipe 123 is connected to the air inlet of the air cooler 300, and the return port 220 is connected to the outlet 1221a of the working medium outlet pipe 122.

[0057] The air outlet of the air cooler 300 is connected to the first inlet 410 of the regenerator 400, the first outlet 420 of the regenerator 400 is connected to the air inlet of the evaporator 500, the air outlet of the evaporator 500 is connected to the second inlet 430 of the regenerator 400, and the second outlet 440 of the regenerator 400 is connected to the inlet 1212 of the working medium inlet pipe 121 of the gas-liquid separator 100.

[0058] The outdoor unit 10 further includes a valve assembly 600, a throttling assembly 700 and a bypass 800. The valve assembly 600 includes a first stop valve 610, a second stop valve 620 and a defrost bypass valve 630. The throttling assembly 700 includes a throttling valve 710 and a defrost capillary tube 720. The first stop valve 610 is arranged on the first pipeline, the second stop valve 620 is arranged on the second pipeline, and the throttling valve 710 is arranged between the first outlet 420 of the regenerator 400 and the air inlet of the evaporator 500. The bypass 800 connects the exhaust port 210 of the compressor 200 and the air inlet of the evaporator 500. The defrost bypass valve 630 and the defrost capillary tube 720 are arranged in series on the bypass 800.

[0059] Bypass 800 is used to directly introduce the high-temperature working fluid from the compressor 200 into the evaporator 500, and the heat of the high-temperature gas itself is used to melt the frost layer. This hot gas bypass method allows all the heat energy required in the entire defrosting process to come from the heat storage of the compressor 200 and the work done by the compressor 200, which reduces the heat absorption from the outside during defrosting, reduces the possibility of the outdoor low-temperature air causing the evaporator 500 to frost again, and improves the defrosting heat exchange efficiency.

[0060] In a specific embodiment of the present application, the working fluid of the heat pump system 1 is CO2. In the heating mode, the flow path of the working fluid in the heat pump system 1 is as follows: Figure 2 As shown, the electronic control system controls the first stop valve 610 to open, the second stop valve 620 and the defrost bypass valve 630 to close, and the CO2 flows through the compressor 200 and is compressed into high-temperature and high-pressure gas, and then enters the air cooler 300. In the air cooler 300, the high-temperature CO2 heats the cooling water introduced into the hydraulic module connected to the air cooler 300 to the target temperature, and the CO2 is cooled to a low-temperature state by isobaric cooling; then the CO2 is further cooled in the regenerator 400 to a lower temperature, and the high-pressure CO2 flows through the throttle valve 710, and the pressure and temperature are reduced at the same time. It vaporizes and absorbs heat in the evaporator 500 to the saturated gas point, and enters the regenerator 400 again to be heated, thereby completing the working cycle of the heat pump system 1 in the heating mode.

[0061] In the defrost mode, the flow path of the working fluid in the heat pump system 1 is as follows: Figure 3 As shown, the electronic control system controls the first stop valve 610 to be closed, the second stop valve 620 and the defrost bypass valve 630 to be opened, the cooling water inlet side of the air cooler 300 is not introduced or partially introduced, and the CO2 flows through the compressor 200 and is compressed into high-temperature and high-pressure gas, and then is discharged from the exhaust port 210 of the compressor 200, flows into the gas-liquid separator 100 through the gas pipe inlet 1233 of the high-pressure gas pipe 123, exchanges heat with the low-temperature and low-pressure CO2 stored in the accommodating chamber 111 of the gas-liquid separator 100 on the high and low pressure sides, and then flows out from the gas pipe outlet 1234 of the high-pressure gas pipe 123, flows through the air cooler 300 and the regenerator 400 in turn, becomes a high-pressure and low-temperature state, and then flows through the throttle valve 710, and the pressure and The temperature is reduced at the same time, and it merges with the other part of the low-pressure and high-temperature CO2 that flows into the bypass 800 through the exhaust port 210 of the compressor 200, and then flows through the defrost capillary 720 and is throttled and reduced in pressure, and then enters the evaporator 500 to be defrosted by high temperature. After defrosting, the low-temperature and low-pressure CO2 passes through the regenerator 400, and flows into the accommodating chamber 111 of the gas-liquid separator 100 from the inlet port 1212 of the working fluid inlet pipe 121, and is converted into low-pressure gaseous CO2 through heat exchange with the high-pressure gas pipe 123 and the high-pressure gaseous CO2 circulating in the heat exchange component 130 in the gas-liquid separator 100, and enters the compressor 200 through the working fluid outlet pipe 122, thereby the heat pump system 1 completes the working cycle in the defrost mode.

[0062] Specifically, the heat exchange assembly 130 includes a partition 131 and a plurality of heat exchange plates 132. The partition 131 is disposed in the high-pressure gas pipe 123 and partitions the interior of the high-pressure gas pipe 123 to form an inlet pipe section 1231 and an outlet pipe section 1232. The inlet pipe section 1231 is used to connect the compressor 200, and the outlet pipe section 1232 is used to connect the air cooler 300. It can be understood that the outlet pipe section 1232 is penetrated through the side wall or the bottom wall of the tank body 110 and extends out of the tank body 110. When the outlet pipe section 1232 is penetrated through the side wall of the tank body 110, it prevents the high-temperature and high-pressure gas from leaking from the bottom of the tank body 110 and facilitates the pipe arrangement. When the outlet pipe section 1232 is penetrated through the bottom wall of the tank body 110, it can facilitate the outlet pipe section 1232 to discharge gas from top to bottom by gravity, thereby improving the gas discharge efficiency and thus improving the heat exchange efficiency.

[0063] The heat exchange plate 132 is connected to the outer wall of the high-pressure gas pipe 123, and an air flow channel 133 is provided in the heat exchange plate 132. The air flow channel 133 connects the air inlet pipe section 1231 and the air outlet pipe section 1232. Therefore, the high-temperature and high-pressure gaseous working medium passing through the high-pressure gas pipe 123 can all flow into the heat exchange plate 132, and heat exchange is carried out on the high and low pressure sides of the gas-liquid separator 100.

[0064] The air flow channel 133 includes a plurality of air intake microchannels 1331, a collecting channel 1332 and a plurality of exhaust microchannels 1333 arranged in parallel. The plurality of air intake microchannels 1331 connect the air intake pipe section 1231 and the collecting channel 1332, and the plurality of exhaust microchannels 1333 connect the collecting channel 1332 and the air outlet pipe section 1232. The setting of the air flow channel 133 changes the gas flow direction in the heat exchange component 130, ensuring that the high-temperature and high-pressure gaseous working medium can fully circulate in the heat exchange plate 132, ensuring the heat exchange area, and thereby improving the heat exchange efficiency of the gas-liquid separator 100.

[0065] In the defrost mode, the exhaust port 210 of the compressor 200 introduces high-temperature and high-pressure gaseous working medium into the air pipe inlet 1233 of the high-pressure air pipe 123, and flows from the air inlet pipe section 1231 to the air inlet microchannel 1331, and flows through the collecting channel 1332 and the exhaust microchannel 1333 in sequence, and then flows from the exhaust microchannel 1333 to the air outlet pipe section 1232 of the high-pressure air pipe 123, and flows into the air inlet of the air cooler 300 from the air pipe outlet 1234. During the whole process, the high-temperature and high-pressure gaseous working medium in the high-pressure air pipe 123 is continuously exchanged with the low-temperature and low-pressure working medium flowing into the tank body 110 from the working medium inlet pipe 121, which can greatly improve the rate at which the low-temperature and low-pressure liquid working medium is converted into a gaseous working medium through high-temperature evaporation, and can also heat the low-temperature and low-pressure gaseous working medium, increase its temperature before entering the compressor 200, improve the working efficiency of the compressor 200, and thus improve the working efficiency of the heat pump system 1.

[0066] It can be understood that there are multiple heat exchange plates 132, and the multiple heat exchange plates 132 are arranged around the high-pressure air pipe 123 and are radially distributed along the radial direction of the high-pressure air pipe 123, which can achieve more uniform temperature distribution, increase the heat exchange area, and allow multiple heat exchange plates 132 to be adjusted according to different application requirements. For example, by changing the size or position of the radiation range to adapt to specific pipe wall size requirements, and this form of heat exchange plate 132 is relatively simple in manufacturing process, so as to reduce costs while ensuring the heat exchange area.

[0067] In some embodiments, the tank body 110 includes a container body 112, an upper end cover 113 and a lower end cover 114 connected to each other. The three can be connected by welding or other means to ensure the connection strength, and the split design facilitates the control of the manufacturing process. At the same time, when maintenance or replacement of parts is required, it can be more easily disassembled and reassembled. The upper end cover 113 and the lower end cover 114 are arranged relative to each other in the upper and lower directions of the tank body 110. The container body 112, the upper end cover 113 and the lower end cover 114 are enclosed to form a accommodating chamber 111, which can provide a stable storage and gasification space for the working fluid and reduce the risk of leakage of liquid working fluid on the bottom wall. The working fluid inlet pipe 121 and the working fluid outlet pipe 122 are both fixedly arranged on the upper end cover 113, and the high-pressure gas pipe 123 is passed through the upper end cover 113 and the container body 112, which can optimize the flow path of the working fluid in the accommodating chamber 111, reduce flow resistance, and improve gasification efficiency.

[0068] It is understandable that the tank body 110 may not be provided with the lower end cover 114, but the container body 112 and the upper end cover 113 enclose the accommodating cavity 111, that is, the bottom wall and the side wall of the container body 112 are of an integrated structure, which can save production costs and can further ensure the airtightness of the container body 112 to avoid leakage.

[0069] The working medium inlet pipe 121 has an inlet pipe outlet 1211 located in the accommodating chamber 111, and the working medium outlet pipe 122 has an outlet pipe inlet 1222a located in the accommodating chamber 111, wherein the inlet pipe outlet 1211 is located above the heat exchange component 130. When the low-temperature and low-pressure liquid working medium flows into the accommodating chamber 111 from the inlet pipe outlet 1211 of the working medium inlet pipe 121, the low-temperature and low-pressure liquid working medium falls from top to bottom to the bottom wall of the accommodating chamber 111. During the falling process, the low-temperature and low-pressure liquid The liquid working medium can exchange heat once with the high-pressure gas pipe 123 and the high-temperature and high-pressure gaseous working medium in the heat exchange component 130, and when the liquid working medium on the bottom wall of the cavity is vaporized, it rises from bottom to top and flows into the working medium outlet pipe 122 from the outlet pipe inlet 1222a. During the rising process, the gaseous working medium can further exchange heat twice with the high-pressure gas pipe 123 and the high-temperature and high-pressure gaseous working medium in the heat exchange component 130, thereby extending the heat exchange time and further improving the heat exchange efficiency.

[0070] In addition, the inlet and outlet 1211 is located in the accommodating chamber 111 near the upper end cover 113, so that the liquid working medium flowing into the accommodating chamber 111 has a longer flow path, increasing the heat exchange time of the liquid working medium before accumulating to the bottom wall in the accommodating chamber 111, thereby improving the heat exchange efficiency.

[0071] Furthermore, the outlet inlet 1222a is arranged higher than the inlet outlet 1211, so that the higher outlet inlet 1222a transmitted from the inlet outlet 1211 to the accommodating chamber 111 helps to reduce the mixing between the gaseous working medium and the working medium flowing out from the inlet outlet 1211, thereby maintaining effective separation of the gaseous and liquid working medium.

[0072] In addition, the inlet and outlet 1211 is arranged toward the inner wall of the tank body 110, and the liquid working medium can flow under the guidance of the side wall of the cavity. It can be understood that in the process of the working medium flowing downward along the side wall of the cavity, the working medium forms a wider flowing liquid surface. When the heat exchange component 130 is used for heat exchange, the heat exchange effect can be effectively improved, thereby making the gas-liquid separation sufficient and reducing the liquid working medium from entering the working medium outlet pipe 122; and the outlet inlet 1222a of the working medium outlet pipe 122 is arranged toward the cavity top wall of the accommodating cavity 111, that is, the inlet and outlet 1211 and the outlet inlet 1222a are arranged in different directions. In this way, In order to prevent the liquid working medium flowing out from the inlet outlet 1211 of the working medium inlet pipe 121 from flowing into the outlet inlet 1222a of the working medium outlet pipe 122 before being vaporized, the working medium entering the inlet outlet 1211 needs to flow in the accommodating chamber 111 and undergo a gas-liquid separation process. At the same time, the working medium will not directly impact the working medium outlet pipe 122, thereby reducing the impact on the working medium outlet pipe 122 and the vibration of the working medium outlet pipe 122. In addition, the outlet inlet 1222a is arranged toward the top wall of the accommodating chamber 111, which can also better gather and discharge the gaseous working medium rising to the top of the accommodating chamber 111, thereby further improving the gas-liquid separation effect.

[0073] The side wall of the accommodating chamber 111 includes a working medium flow area. Since the inlet and outlet 1211 of the working medium inlet pipe 121 is arranged toward the side wall of the accommodating chamber 111, the working medium sprayed from the inlet and outlet 1211 to the side wall of the chamber falls to form a working medium flow area. The liquid working medium adheres to the side wall of the chamber and can effectively slow down its falling speed. This is because the contact between the liquid and the solid surface can increase the friction resistance, thereby slowing down the falling speed, so that the time for the liquid working medium to generate heat exchange during the falling process is extended, thereby achieving the purpose of improving the heat exchange effect.

[0074] In some embodiments, Figures 5 to 7As shown, from the shape of the working medium outlet pipe 122, the working medium outlet pipe 122 includes a first part 1221 and a second part 1222 connected to each other, the first part 1221 extends outside the container body 112, is fixed to the upper end cover 113 and is used to connect with the compressor 200, and the second part 1222 is located in the accommodating chamber 111 and connected to the first part 1221. The second part 1222 is U-shaped, that is, the second part 1222 is a curved pipe, so it is more difficult for the liquid working medium in the accommodating chamber 111 to flow into the second part 1222 to the compressor 200, which can enhance the anti-liquid backflow effect of the gas-liquid separator 100.

[0075] Specifically, the second part 1222 includes at least two vertical portions 1222b extending in the up and down directions of the gas-liquid separator 100 and a bending portion 1222c connected to two adjacent vertical portions 1222b. The provision of at least two vertical portions 1222b can increase the flow path of the working fluid entering the tube, thereby providing more heat exchange time and a larger heat exchange area.

[0076] In some embodiments, Figure 6 and Figure 7 As shown, at least one oil return hole 1223 is provided on the part of the medium outlet pipe 122 located in the accommodating chamber 111 near the bottom of the tank body 110. In the gas-liquid separator 100, the separated and accumulated liquid medium will dissolve in oil. If the oil return hole 1223 is not provided, the lubricating oil in the compressor 200 will become less and less, and the lubricating oil deposited in the gas-liquid separator 100 will become more and more. Therefore, it is necessary to return the oil to the compressor 200 to ensure the oil volume in the compressor 200 and the oil supply to the vortex part. The provision of at least one oil return hole 1223 can enable the liquid medium dissolved in oil to return to the compressor 200 through other paths. It can be understood that the oil return hole 1223 is provided at the second part 1222 of the medium outlet pipe 122 near the bottom of the tank body 110, which can facilitate the oil to fall back to the bottom wall of the accommodating chamber 111 by gravity during the gas outlet process of the medium outlet pipe 122.

[0077] In some embodiments, the gas-liquid separator 100 also includes a support assembly 115, which can be welded to the lower end cover 114 or the container body 112. The support assembly 115 is located near the bottom of the tank body 110, which can lower the center of gravity of the entire tank body 110 and enhance its stability when fixed to the casing of the outdoor unit 10.

[0078] Exemplarily, the support assembly 115 includes four mounting feet, which are circumferentially welded to the container body 112 to enhance the structural stability of the container body 112, more evenly distribute the weight and possible vibration loads of the tank body 110, and reduce the pressure on the casing of the outdoor unit 10.

[0079] The present application also proposes a control method, which is used for the heat pump system 1 as described above. The specific structure of the heat pump system 1 refers to the above embodiment. Figure 2 , Figure 3 as well as Figure 8 , the control method comprises the following steps:

[0080] Collect the outdoor air temperature t1 and humidity parameters, set the evaporator 500 fin temperatures t3 and t4. In a specific embodiment of the present application, the preset values ​​t3 and t4 are 0°C. According to the collected outdoor air temperature t1 and humidity parameters, determine whether the evaporator 500 is likely to be frosted. When t1 is less than or equal to 0°C, it can be determined that the evaporator 500 is likely to be frosted.

[0081] If there is a possibility of frosting, the fin temperature t2 of the evaporator 500 is collected, and it is determined whether the fin temperature t2 of the evaporator 500 is greater than the preset value t3. If there is no possibility of frosting, that is, t1 is greater than 0°C, the electronic control system controls the first stop valve 610 to open, the second stop valve 620 and the defrost bypass valve 630 to close, so as to operate the heating mode;

[0082] If the fin temperature t2 of the evaporator 500 is less than or equal to the preset value t3, the electronic control system controls the first stop valve 610 to close, the second stop valve 620 and the defrost bypass valve 630 to open, so as to run the defrost mode; if the fin temperature t2 of the evaporator 500 is greater than the preset value t3, the electronic control system controls the first stop valve 610 to open, the second stop valve 620 and the defrost bypass valve 630 to close, so as to continue to run the heating mode;

[0083] After the defrost mode is run, after a preset time t, the evaporator 500 fin temperature t5 is collected, and it is determined whether the evaporator 500 fin temperature t5 is greater than a preset value t4;

[0084] If the fin temperature t5 of the evaporator 500 is less than or equal to the preset value t4, the electronic control system controls the first stop valve 610 to close, and the second stop valve 620 and the defrost bypass valve 630 to open to continue running the defrost mode. If the fin temperature t5 of the evaporator 500 is greater than the preset value t4, the electronic control system controls the first stop valve 610 to open, and the second stop valve 620 and the defrost bypass valve 630 to close to run the heating mode.

[0085] In some embodiments, the method of collecting outdoor air temperature and humidity includes but is not limited to using sensors, thermometers and other devices. In this case, the temperature and humidity are collected using sensors. The sensors can be temporarily placed by technicians at any position of the outdoor unit 10 of the heat pump system 1, and temperature measurements are obtained at these positions, and the data is transmitted to the processor. Of course, the collection method can also be through weather monitoring, collecting weather forecasts, etc.

[0086] The electronic control system may include a cloud computing module having hardware (e.g., a processor and / or memory) and software capable of performing the following functions, in which the electronic control system may obtain weather monitoring and / or weather forecasts via, for example, the Internet, Bluetooth, or cellular connections. When the electronic control system is provided with a processor, the collected temperature and humidity parameters may be processed and control instructions may be output to switch the operating mode of the heat pump system 1. The processor may also communicate with a server, which may, for example, receive data from a sensor via a network connection or a cellular network. The processor may receive data from a sensor on demand, intermittently, or in real time. The processor may be located on a portable computing device of a contractor or technician, such as a laptop, tablet computer, smart phone, or other device, or in a house or building in which the heat pump system 1 is installed, such as in a thermostat or control module for the heat pump system 1.

[0087] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of this application, it should be understood that if the terms "up", "down", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0088] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A gas-liquid separator, applied to a heat pump system, characterized in that: include: A tank body having a receiving cavity formed therein; A working fluid pipe assembly, comprising a working fluid inlet pipe, a working fluid outlet pipe and a high-pressure gas pipe which are arranged on the tank body at intervals, wherein a portion of the working fluid inlet pipe is located outside the tank body, and another portion is located inside the accommodating cavity and is used to communicate with the accommodating cavity, a portion of the working fluid outlet pipe is located outside the tank body, and another portion is located inside the accommodating cavity and is used to communicate with the accommodating cavity, and the high-pressure gas pipe is passed through the tank body, and both ends of the high-pressure gas pipe are located outside the tank body; and The heat exchange component is arranged in the accommodating cavity and is arranged on the pipe section of the high-pressure gas pipe located in the accommodating cavity.

2. The gas-liquid separator according to claim 1, characterized in that: The heat exchange assembly includes a partition and a plurality of heat exchange plates, wherein the partition is arranged in the high-pressure air pipe and partitions the interior of the high-pressure air pipe to form an air inlet pipe section and an air outlet pipe section; The heat exchange plate is connected to the outer wall of the high-pressure air pipe, and an air flow passage is arranged inside the heat exchange plate, and the air flow passage communicates the air inlet pipe section and the air outlet pipe section.

3. The gas-liquid separator according to claim 2, characterized in that: A plurality of heat exchange plates are provided, and the plurality of heat exchange plates are arranged around the high-pressure air pipe and are radially distributed along the radial direction of the high-pressure air pipe.

4. The gas-liquid separator according to claim 2, characterized in that: The air flow passage includes a plurality of air intake microchannels and a manifold arranged in parallel, and a plurality of exhaust microchannels arranged in parallel. The plurality of air intake microchannels connect the air intake pipe section and the manifold, and the plurality of exhaust microchannels connect the manifold and the air outlet pipe section.

5. The gas-liquid separator according to claim 2, characterized in that: The air outlet pipe section is arranged through the side wall or the bottom wall of the tank body and extends out of the tank body.

6. The gas-liquid separator according to any one of claims 2 to 5, characterized in that: The working medium inlet pipe has an inlet pipe outlet located in the accommodating cavity, wherein the inlet pipe outlet is located above the heat exchange component.

7. The gas-liquid separator according to claim 6, characterized in that: The inlet pipe outlet is arranged toward the inner side wall of the tank body.

8. The gas-liquid separator according to claim 6, characterized in that: The working medium outlet pipe has an outlet inlet located in the accommodating cavity, the outlet inlet is adjacent to the top of the tank body and is arranged higher than the inlet outlet.

9. The gas-liquid separator according to any one of claims 1 to 5, characterized in that: The tank body includes a container body and an upper end cover connected to each other. The container body and the upper end cover enclose the accommodating cavity. The working fluid inlet pipe and the working fluid outlet pipe are both fixedly arranged on the upper end cover. The high-pressure gas pipe passes through the upper end cover and the container body.

10. A heat pump system, characterized in that: An outdoor unit and a hydraulic module connected by pipelines, wherein the outdoor unit comprises a compressor, an air cooler, a regenerator, an evaporator and a gas-liquid separator as claimed in any one of claims 1 to 9 connected by pipelines, and the hydraulic module comprises the air cooler; The compressor has an exhaust port and an air return port, a first pipeline and a second pipeline are arranged in parallel at the exhaust port of the compressor, the exhaust port is connected to the air inlet of the air cooler through the first pipeline, the exhaust port is connected to the air pipe inlet of the high-pressure air pipe through the second pipeline, the air pipe outlet of the high-pressure air pipe is connected to the air inlet of the air cooler, and the air return port is connected to the outlet of the working medium outlet pipe; The air outlet of the air cooler is connected to the first inlet of the regenerator, the first outlet of the regenerator is connected to the air inlet of the evaporator, the air outlet of the evaporator is connected to the second inlet of the regenerator, and the second outlet of the regenerator is connected to the inlet of the working medium inlet pipe of the gas-liquid separator; The outdoor unit further comprises a valve assembly and a throttling assembly, wherein the valve assembly comprises a first stop valve, a second stop valve and a defrost bypass valve, the throttling assembly comprises a throttling valve and a defrost capillary tube, the first stop valve is arranged on the first pipeline, the second stop valve is arranged on the second pipeline, and the throttling valve is arranged between the first outlet of the regenerator and the air inlet of the evaporator; The outdoor unit further comprises a bypass, wherein the bypass connects the exhaust port of the compressor and the air inlet of the evaporator, and the defrost bypass valve and the defrost capillary tube are arranged in series on the bypass.

11. A control method for the heat pump system according to claim 10, characterized in that the steps include: S1: Collecting outdoor air temperature t1 and humidity parameters, setting evaporator fin temperatures t3 and t4, and judging whether the evaporator is likely to be frosted based on the collected outdoor air temperature t1 and humidity parameters; S2: If there is a possibility of frosting, the evaporator fin temperature t2 is collected, and it is determined whether the evaporator fin temperature t2 is greater than the preset value t3; if there is no possibility of frosting, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to operate the heating mode; S3: If the evaporator fin temperature t2 is less than or equal to the preset value t3, the first stop valve is controlled to be closed, and the second stop valve and the defrost bypass valve are controlled to be opened to run the defrost mode. If the evaporator fin temperature t2 is greater than the preset value t3, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to continue running the heating mode.

12. The control method according to claim 11, characterized in that: After the defrost mode is run, after a preset time t, the evaporator fin temperature t5 is collected, and it is determined whether the evaporator fin temperature t5 is greater than the preset value t4; If the evaporator fin temperature t5 is less than or equal to the preset value t4, the first stop valve is controlled to be closed, and the second stop valve and the defrost bypass valve are controlled to be opened to continue running the defrost mode. If the evaporator fin temperature t5 is greater than the preset value t4, the first stop valve is controlled to be opened, and the second stop valve and the defrost bypass valve are controlled to be closed to run the heating mode.

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