A heat pump system

Abstract

The embodiment of the application provides a heat pump system, and relates to the technical field of heat pumps. The heat pump system comprises a compressor, an evaporator, a first three-way valve, an auxiliary valve, a second three-way valve and a third three-way valve. The compressor comprises an exhaust port, a gas supplement port and a liquid return port. The evaporator comprises a first heat exchange unit and a second heat exchange unit. The first heat exchange unit comprises a plurality of first fins and a first pipeline penetrating the first fins. The second heat exchange unit comprises a plurality of second fins and a second pipeline penetrating the second fins. The first fins and the second fins are arranged in an interlaced and laminated mode. The first three-way valve is connected with the exhaust port, the first pipeline and the second pipeline respectively. The auxiliary valve is connected with the gas supplement port. The first pipeline is connected with the auxiliary valve and the liquid return port through the second three-way valve. The second pipeline is connected with the auxiliary valve and the liquid return port through the third three-way valve. The heat pump system realizes defrosting and heat supply simultaneously, and ensures normal operation of the system during defrosting.

Description

Technical Field

[0001] This application relates to the field of heat pump technology, and more particularly to a heat pump system. Background Technology

[0002] Heat pump systems are typically used for heating, hot water supply, and industrial heating in low-temperature and high-humidity environments. When existing heat pumps are operating in heating mode, the evaporator temperature is usually lower than the condensation temperature of the ambient temperature. When the air temperature drops below 0°C, this water vapor forms a frost layer on the evaporator, affecting the normal operation of the heat pump, leading to decreased efficiency, or even shutdown. Therefore, defrosting is necessary for the heat pump.

[0003] Existing defrosting operations typically employ four-way valve switching defrosting or compressor hot gas bypass defrosting. However, existing defrosting technologies require stopping heating during defrosting, causing heating interruptions and affecting the normal operation of the system. Summary of the Invention

[0004] This application provides a heat pump system that enables simultaneous defrosting and heating, ensuring normal operation of the system during defrosting.

[0005] This application provides a heat pump system, including: a compressor, including an exhaust port, an air inlet, and a liquid return port; an evaporator, including a first heat exchange unit and a second heat exchange unit, the first heat exchange unit including a plurality of first fins and a first pipe passing through the first fins, the second heat exchange unit including a plurality of second fins and a second pipe passing through the second fins, the first fins and the second fins being alternately stacked;

[0006] A first three-way valve is connected to the exhaust port, the first pipeline, and the second pipeline respectively; an auxiliary valve is connected to the air supply port; a second three-way valve is connected to the first pipeline, which is connected to the auxiliary valve and the return port respectively; and a third three-way valve is connected to the second pipeline, which is connected to the auxiliary valve and the return port respectively.

[0007] In one possible implementation, the first three-way valve includes a first valve inlet, a first valve outlet, and a second valve outlet, wherein the first valve inlet is connected to the exhaust port, the first valve outlet is connected to the first pipeline, and the second valve outlet is connected to the second pipeline.

[0008] In one possible implementation, the second three-way valve includes: a second valve inlet, a third valve outlet, and a fourth valve outlet; the second valve inlet is connected to the first pipeline; the third valve outlet is connected to the auxiliary valve; and the fourth valve outlet is connected to the return port.

[0009] In one possible implementation, the third three-way valve includes: a third valve inlet, a fifth valve outlet, and a sixth valve outlet; the third valve inlet is connected to the second pipeline; the fifth valve outlet is connected to the auxiliary valve; and the sixth valve outlet is connected to the return port.

[0010] In one possible implementation, the first pipeline includes: a first main pipe connected to the outlet of the first valve; a first branch pipe, of which there are multiple branch pipes, each branch pipe passing through the first fin and connected to the first main pipe, the multiple branch pipes converging and connected to the inlet of the second valve; and a first main valve located at the first main valve, the opening of which is adjustable.

[0011] In one possible implementation, the second pipeline includes: a second main pipe connected to the outlet of the second valve; a second branch pipe, of which there are multiple branch pipes, each branch pipe passing through the second fin and connected to the second main pipe, the multiple branch pipes converging and then connected to the inlet of the third valve; and a second main valve, located at the second main valve, the opening of which is adjustable.

[0012] In one possible implementation, a water-side heat exchanger is also included, located between the exhaust port and the first valve inlet.

[0013] In one possible implementation, the auxiliary valve is also connected to a pipeline between the exhaust port and the inlet of the first valve.

[0014] In one possible implementation, the device further includes a heat exchanger having a first heat exchange channel and a second heat exchange channel; the two ends of the first heat exchange channel are respectively connected to a pipeline between the water-side heat exchanger and the inlet of the first valve; the two ends of the second heat exchange channel are respectively connected to a pipeline between the auxiliary valve and the air supply port.

[0015] In one possible implementation, it further includes: a first control valve, which is located on the pipeline between the auxiliary valve and the upstream side of the first valve inlet.

[0016] In one possible implementation, an auxiliary flow path is connected between the first pipeline and the second pipeline, and a second control valve is provided on the auxiliary flow path.

[0017] In one possible implementation, the heat pump system includes a heating mode in which the first pipeline is connected to the outlet of the first valve, and the second pipeline is connected to the outlet of the second valve; the opening degree of the first main valve and the second main valve is at a first preset opening degree value.

[0018] In one possible implementation, the heat pump system includes a heating defrosting mode, wherein in the heating defrosting mode, the first pipeline is connected to the outlet of the first valve, and the second pipeline is connected to the outlet of the second valve; the opening degree of the main valve corresponding to the one to be defrosted in the first heat exchange unit and the second heat exchange unit is at a first preset opening degree value, and the opening degree of the main valve corresponding to the one to be defrosted and heated is at a second preset opening degree value, wherein the second preset opening degree value is greater than the first preset opening degree value.

[0019] In one possible implementation, the heat pump system includes an ultra-low temperature heating defrosting mode. In this mode, the first pipeline is connected to the outlet of the first valve, and the second pipeline is connected to the outlet of the second valve. The main valve corresponding to the unit to be defrosted in the first and second heat exchange units is at a first preset opening value, and the main valve corresponding to the unit undergoing defrosting and heating is at a second preset opening value, which is greater than the first preset opening value. An auxiliary flow path is connected between the first pipeline and the second pipeline, and the control valve of the auxiliary flow path is open.

[0020] The heat pump system provided in this application has at least the following advantages.

[0021] The connection of the aforementioned components forms a refrigerant circuit with dual independent evaporators, capable of flow distribution and direction switching. This heat pump system can achieve multiple operating modes. In defrost mode, the refrigerant flow is distributed through the first three-way valve, allowing a portion of the high-temperature refrigerant to flow into the evaporator unit requiring defrosting (such as the first pipeline) for heat release defrosting. After defrosting, the refrigerant can be selectively throttled through the auxiliary valve and enter the compressor's gas injection port. Simultaneously, another portion of the refrigerant flows normally into another evaporator unit (such as the second pipeline) for heat absorption and heating. After heat absorption, the refrigerant returns directly to the compressor's liquid return port. In this way, while one evaporator unit is defrosting, the other evaporator unit continuously absorbs heat from the air to maintain the system's heating output, avoiding heating interruptions caused by traditional defrosting methods. The staggered fin design allows the two heat exchange units to be physically tightly integrated, facilitating the more effective transfer of heat generated on the defrosting side to the frosting area, while the heat absorption process on the other side can still proceed effectively.

[0022] This application achieves simultaneous forward-cycle defrosting and heating by coupling dual flow paths within a single evaporator, and utilizes the subcooled liquid refrigerant generated during defrosting for enthalpy boosting. This solution changes the traditional mutually exclusive operation of heating and defrosting, integrating the defrosting process into a thermodynamic stage that provides both subcooling and enthalpy boosting. The subcooled liquid refrigerant generated after defrosting releases heat is used to boost the compressor's enthalpy, thereby improving system efficiency in low-temperature environments without interrupting heat supply to the water side. This design uses a three-way valve to switch and control the refrigerant flow path, achieving continuous heating during defrosting without significantly increasing system cost or installation space.

[0023] This allows for continuous heating during defrosting. In defrosting mode, the water-side heat exchanger always functions as a condenser, continuously releasing heat to the connected water tank or heating terminal, which helps avoid heating interruptions that occur in traditional defrosting methods.

[0024] Secondly, the system exhibits high stability in outlet water temperature and minimal fluctuation in the coefficient of performance (COP). Because the condensation process of the water-side heat exchanger continues during defrosting, its outlet water temperature does not drop significantly due to defrosting. Consequently, the system's operating efficiency remains relatively stable throughout the defrosting cycle, avoiding the sharp drop in COP that occurs with traditional units during defrosting.

[0025] Furthermore, the system employs a dual-flow-path coupling design within a single evaporator, avoiding the uneven airflow and refrigerant flow distribution issues that can occur with two independent evaporators. This system primarily utilizes the sensible heat of the high-temperature refrigerant for defrosting, specifically the heat released during the cooling process of the condensed refrigerant to melt the frost layer. Simultaneously, the coupled evaporator structure design allows for more efficient utilization of the heat released on the defrosting side, helping to reduce heat dissipation during the defrosting process.

[0026] Furthermore, secondary subcooling of the refrigerant is achieved simultaneously with defrosting. The refrigerant flowing out from the defrost side, after being throttled, exchanges heat with the main refrigerant through the economizer. This increases the subcooling of the refrigerant flowing to the heating evaporator on the other side, thereby enhancing its heat absorption capacity. On the other hand, the evaporated refrigerant replenishes the compressor, increasing its enthalpy, which significantly improves the system's heating capacity under low-temperature conditions. Simultaneously, the complete evaporation of this refrigerant in the economizer prevents it from entering the compressor in liquid form, helping to mitigate the risk of liquid slugging in the compressor.

[0027] Finally, it helps avoid the risk of liquid slugging in the compressor. In traditional systems, when switching back to heating after defrosting, the sudden pressure change during the four-way valve reversal can easily cause liquid refrigerant to rush into the compressor. This alternating defrosting system does not require a large pressure reversal in the main circuit during the entire mode switching process, resulting in a smoother change in system operating status and improved operational stability. Attached Figure Description

[0028] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0029] Figure 1 A schematic diagram of the heat pump system provided in this application.

[0030] Explanation of reference numerals in the attached figures:

[0031] 10-Compressor; 11-Exhaust port; 12-Inlet gas port; 13-Liquid return port;

[0032] 20 - Evaporator; 210 - First heat exchange unit; 211 - First pipeline; 2111 - First main pipe; 2112 - First branch pipe; 2113 - First main valve; 220 - Second heat exchange unit; 221 - Second pipeline; 2211 - Second main pipe; 2212 - Second branch pipe; 2213 - Second main valve; 230 - Auxiliary flow path; 231 - Second control valve;

[0033] 30 - First three-way valve;

[0034] 40 - Auxiliary valve;

[0035] 50 - Second three-way valve;

[0036] 60 - Third three-way valve;

[0037] 70 - Water-side heat exchanger;

[0038] 80 - Heat exchanger;

[0039] 90 - First control valve.

[0040] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0041] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0042] Heat pump systems are typically used for heating, hot water supply, and industrial heating in low-temperature and high-humidity environments. When existing heat pumps are operating in heating mode, the evaporator temperature is usually lower than the condensation temperature of the ambient temperature. When the air temperature drops below 0°C, this water vapor forms a frost layer on the evaporator, affecting the normal operation of the heat pump, leading to decreased efficiency, or even shutdown. Therefore, defrosting is necessary for the heat pump.

[0043] Existing defrosting operations typically employ four-way valve switching defrosting or compressor hot gas bypass defrosting. However, existing defrosting technologies require stopping heating during defrosting, causing heating interruptions and affecting the normal operation of the system.

[0044] In view of this, this application provides a heat pump system that, through the connection of the aforementioned components, forms a refrigerant circuit with dual independent evaporators and the ability to distribute and switch flow directions. This heat pump system can achieve multiple operating modes. In defrost mode, the refrigerant flow is distributed through a first three-way valve, allowing a portion of the high-temperature refrigerant to flow into the evaporator unit requiring defrosting (such as the first pipeline) for heat release and defrosting. The defrosted refrigerant can then be throttled via an auxiliary valve and enter the compressor's gas injection port. Simultaneously, another portion of the refrigerant flows normally into another evaporator unit (such as the second pipeline) for heat absorption and heating. The heat-absorbed refrigerant returns directly to the compressor's liquid return port. In this way, while one evaporator unit is defrosting, the other evaporator unit continuously absorbs heat from the air to maintain the system's heating output, avoiding heating interruptions caused by traditional defrosting methods. The staggered fin design allows the two heat exchange units to be physically tightly integrated, facilitating the more effective transfer of heat generated on the defrosting side to the frosting area, while the heat absorption process on the other side can still proceed effectively.

[0045] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0046] Combination Figure 1This application provides a heat pump system including a compressor 10, an evaporator 20, a first three-way valve 30, an auxiliary valve 40, a second three-way valve 50, and a third three-way valve 60. The compressor 10 includes an exhaust port 11, a gas inlet 12, and a liquid return port 13. The evaporator 20 includes a first heat exchange unit 210 and a second heat exchange unit 220. The first heat exchange unit 210 includes multiple first fins and a first pipe 211 passing through the first fins. The second heat exchange unit 220 includes multiple second fins and a second pipe 221 passing through the second fins. The first and second fins are staggered and stacked. The first three-way valve 30 is connected to the exhaust port 11, the first pipe 211, and the second pipe 221, respectively. The auxiliary valve 40 is connected to the gas inlet 12. The first pipe 211 is connected to the auxiliary valve 40 and the liquid return port 13 via the second three-way valve 50, respectively. The second pipeline 221 is connected to the auxiliary valve 40 and the return port 13 via the third three-way valve 60.

[0047] Specifically, the exhaust port 11 of the compressor 10 is the outlet of the high-temperature and high-pressure gaseous refrigerant, the gas inlet 12 of the compressor 10 is used to introduce medium-pressure gaseous refrigerant for gas replenishment and enthalpy increase, and the liquid return port 13 of the compressor 10 is the suction port of the compressor 10, used to return low-pressure gaseous refrigerant.

[0048] The evaporator 20 includes a first heat exchange unit 210 and a second heat exchange unit 220. The first heat exchange unit 210 includes a plurality of first fins and first pipes 211 passing through the interior of these first fins. The second heat exchange unit 220 includes a plurality of second fins and second pipes 221 passing through the interior of these second fins. The first fins and the second fins are arranged in an alternating layered configuration. Optionally, in the overall heat exchange core of the evaporator 20, the fins of the first heat exchange unit 210 and the second heat exchange unit 220 are arranged alternately along the airflow direction, but the first pipes 211 and the second pipes 221 are two independent piping systems.

[0049] The first three-way valve 30 has three ports, which are respectively connected to the exhaust port 11 of the compressor 10, the first pipe 211 of the first heat exchange unit 210, and the second pipe 221 of the second heat exchange unit 220. The flow rate of the high-temperature gaseous refrigerant discharged by the compressor 10 to the first pipe 211 and the second pipe 221 can be controlled by the opening degree of the first three-way valve 30.

[0050] Auxiliary valve 40 is connected to the gas supply port 12 of compressor 10. Auxiliary valve 40 is an adjustable throttling device used to throttle and reduce the pressure of the refrigerant flowing into gas supply port 12. Second three-way valve 50 has three connection ports. The first pipe 211 of evaporator 20 is connected to auxiliary valve 40 and the liquid return port 13 of compressor 10 via second three-way valve 50. Second three-way valve 50 is used to switch the flow direction of refrigerant flowing from the first pipe 211, selectively directing it to auxiliary valve 40 or directly to the liquid return port 13 of compressor 10.

[0051] The third three-way valve 60 has three connection ports. The second pipe 221 of the evaporator 20 is connected to the auxiliary valve 40 and the return port 13 of the compressor 10 respectively through the third three-way valve 60. The third three-way valve 60 is used to switch the flow direction of the refrigerant flowing out of the second pipe 221, so that it selectively flows to the auxiliary valve 40 or directly to the return port 13 of the compressor 10.

[0052] The heat pump system of this embodiment, through the connection of the aforementioned components, constitutes a refrigerant circuit with dual independent evaporators 20 and capable of flow distribution and direction switching. This heat pump system can achieve multiple operating modes. In defrost mode, the refrigerant flow is distributed through the first three-way valve 30, allowing a portion of the high-temperature refrigerant to flow into the evaporator 20 unit requiring defrosting (such as the first pipe 211) for heat release and defrosting. The defrosted refrigerant can then be throttled via the auxiliary valve 40 and enter the compressor 10's gas injection port 12. Simultaneously, another portion of the refrigerant flows normally into another evaporator 20 unit (such as the second pipe 221) for heat absorption and heating. The heat-absorbed refrigerant directly returns to the compressor 10's liquid return port 13. In this way, while one evaporator 20 unit is defrosting, the other evaporator 20 unit continuously absorbs heat from the air to essentially maintain the system's heating output, avoiding heating interruptions caused by traditional defrosting methods. The staggered fin design allows the two heat exchange units to be physically tightly integrated, which helps the heat generated on the defrosting side to be more effectively transferred to the frosting area, while the heat absorption process on the other side can still proceed effectively.

[0053] In some specific examples, the heat pump system can achieve at least three operating modes, including heating without defrosting, heating and defrosting, and heating and defrosting at extremely low temperatures.

[0054] In the normal heating without defrosting mode, the first three-way valve 30 mainly guides the high-temperature gaseous refrigerant discharged from the compressor 10 to the water-side heat exchanger 70 for condensation and heat release. After becoming high-pressure liquid refrigerant, it is then distributed by the first three-way valve 30 into the first pipeline 211 and the second pipeline 221 for evaporation and heat absorption. Finally, it is guided back to the compressor 10 through the second and third three-way valves 60, completing the heating cycle. The gas replenishment and enthalpy enhancement function can be achieved by opening the solenoid valve on the main line, drawing a portion of the liquid refrigerant from the main line, throttling it through the auxiliary valve 40, exchanging heat in the economizer, and then entering the compressor 10 through the gas replenishment port 12.

[0055] In heating and defrosting mode, for example, if defrosting of the first heat exchange unit 210 is required, the system enters the heating and defrosting mode. The first three-way valve 30 adjusts its opening to distribute the high-temperature, high-pressure liquid refrigerant condensed from the compressor 10 discharge port 11 via the water-side heat exchanger 70 to the first pipeline 211 and the second pipeline 221. For the refrigerant flowing to the first pipeline 211 (i.e., the defrosting side), the second three-way valve 50 switches to connect with the auxiliary valve 40. When the medium-temperature refrigerant flows in the first pipeline 211, it releases heat to the frosted first fins and pipeline, melting the frost layer and cooling itself. Subsequently, the refrigerant flows through the second three-way valve 50 into the auxiliary valve 40, where it is throttled and depressurized. It then flows through the economizer for further heat exchange and finally enters the compressor 10 from the gas injection port 12 to participate in the gas injection cycle. The second pipeline 221 operates in the same manner as in the conventional heating without defrosting mode.

[0056] In the heating and defrosting mode under extremely low temperature conditions, while maintaining the aforementioned heating and defrosting flow path, the system can open the solenoid valve connecting the inlet of the first pipe 211 and the inlet of the second pipe 221. When this solenoid valve opens, a portion of the refrigerant originally intended to flow entirely to the first pipe 211, distributed from the first three-way valve 30, will be diverted through this solenoid valve and enter the second pipe 221 on the heating side. This increases the refrigerant mass flow rate participating in the evaporation and heat absorption in the second pipe 221 on the heating side under extremely low temperature conditions. Thus, with the same heat exchange area and temperature difference, the refrigerant flow rate can be increased to increase the total heat absorption. This adjustment helps compensate for the impact of the decrease in evaporation temperature and the reduction in heat absorption per kilogram of refrigerant caused by the extremely low temperature environment, maintaining the system's heating capacity in harsh environments.

[0057] In this mode, the diversion of the first pipe 211 also means that the heat used for the defrosting side of the first pipe 211 is relatively reduced, and the defrosting speed may be slowed down. However, in extremely low temperature environments, the absolute moisture content in the air is low, the actual frosting rate and frost thickness of the evaporator 20 are reduced, and the demand for defrosting heat is also reduced. Therefore, by diverting part of the heat through the solenoid valve to enhance the heating side and matching it with the actual reduced defrosting demand, a balance can be achieved between the heating capacity and defrosting demand of the system in extremely low temperature environments.

[0058] In some embodiments, combined with Figure 1 The first three-way valve 30 includes a first valve inlet, a first valve outlet, and a second valve outlet. The first valve inlet is connected to the exhaust port 11, the first valve outlet is connected to the first pipeline 211, and the second valve outlet is connected to the second pipeline 221.

[0059] Specifically, the inlet of the first valve is connected to the discharge port 11 of the compressor 10, and the high-temperature, high-pressure gaseous refrigerant from the discharge port 11 of the compressor 10 enters the first three-way valve 30 through the first valve inlet. The outlet of the first valve is connected to the first pipe 211 of the evaporator 20, and the refrigerant flowing out of the first three-way valve 30 can flow through the first valve outlet to the first pipe 211 of the first heat exchange unit 210 of the evaporator 20. The outlet of the second valve is connected to the second pipe 221 of the evaporator 20, and the refrigerant flowing out of the first three-way valve 30 can also flow through the second valve outlet to the second pipe 221 of the second heat exchange unit 220 of the evaporator 20.

[0060] With this connection method, the main stream of refrigerant flowing from the discharge port 11 of the compressor 10 condenses into a liquid or gas-liquid two-phase state after passing through the water-side heat exchanger 70, and then enters the first valve inlet of the first three-way valve 30. Inside the first three-way valve 30, the opening degree and position of the valve core determine the ratio of refrigerant flowing in from the first valve inlet to the first valve outlet and the second valve outlet. By adjusting the first three-way valve 30, the refrigerant flow distribution between the first pipe 211 and the second pipe 221 entering the evaporator 20 can be controlled.

[0061] In some embodiments, combined with Figure 1 The second three-way valve 50 includes a second valve inlet, a third valve outlet, and a fourth valve outlet. The second valve inlet is connected to the first pipeline 211, the third valve outlet is connected to the auxiliary valve 40, and the fourth valve outlet is connected to the return port 13.

[0062] Specifically, the inlet of the second valve is connected to the first pipe 211 of the evaporator 20. The refrigerant flowing out of the first pipe 211 of the first heat exchange unit 210 of the evaporator 20 enters the second three-way valve 50 through the inlet of the second valve. The outlet of the third valve is connected to the auxiliary valve 40. The refrigerant flowing out of the second three-way valve 50 can flow through the outlet of the third valve to the auxiliary valve 40, which is connected to the gas supply port 12 of the compressor 10. The outlet of the fourth valve is connected to the liquid return port 13 of the compressor 10. The refrigerant flowing out of the second three-way valve 50 can also flow directly to the liquid return port 13 of the compressor 10 through the outlet of the fourth valve.

[0063] With this connection method, the second three-way valve 50 is used to control the final destination of the refrigerant flowing out of the first pipeline 211. When the valve core of the second three-way valve 50 connects the second valve inlet to the fourth valve outlet, the refrigerant flowing out of the first pipeline 211 will directly return to the liquid return port 13 of the compressor 10. This corresponds to the mode in which the first heat exchange unit 210 operates normally as the heating side. When the valve core of the second three-way valve 50 connects the second valve inlet to the third valve outlet, the refrigerant flowing out of the first pipeline 211 will flow to the auxiliary valve 40. After being throttled and depressurized by the auxiliary valve 40, it enters the gas injection port 12 of the compressor 10. This corresponds to the mode in which the first heat exchange unit 210 operates as the defrosting side. By switching the second three-way valve 50, the role and functional path of the first pipeline 211 in the system circulation can be flexibly changed. The switching between the heating and defrosting functions of the first heat exchange unit 210 can be achieved without changing the physical connection of the pipeline.

[0064] In some embodiments, combined with Figure 1 The third three-way valve 60 includes a third valve inlet, a fifth valve outlet, and a sixth valve outlet. The third valve inlet is connected to the second pipeline 221, the fifth valve outlet is connected to the auxiliary valve 40, and the sixth valve outlet is connected to the return port 13.

[0065] Specifically, the inlet of the third valve is connected to the second pipe 221 of the evaporator 20. The refrigerant flowing out of the second pipe 221 of the second heat exchange unit 220 of the evaporator 20 enters the third three-way valve 60 through the inlet of the third valve. The outlet of the fifth valve is connected to the auxiliary valve 40. The refrigerant flowing out of the third three-way valve 60 can flow through the outlet of the fifth valve to the auxiliary valve 40 connected to the gas supply port 12 of the compressor 10. The outlet of the sixth valve is connected to the liquid return port 13 of the compressor 10. The refrigerant flowing out of the third three-way valve 60 can also flow directly to the liquid return port 13 of the compressor 10 through the outlet of the sixth valve.

[0066] With this connection method, the third three-way valve 60 is used to independently control the final destination of the refrigerant flowing out of the second pipeline 221. When the valve core of the third three-way valve 60 connects the third valve inlet to the sixth valve outlet, the refrigerant flowing out of the second pipeline 221 will directly return to the liquid return port 13 of the compressor 10. This corresponds to the mode in which the second heat exchange unit 220 operates normally as the heating side. When the valve core of the third three-way valve 60 connects the third valve inlet to the fifth valve outlet, the refrigerant flowing out of the second pipeline 221 will flow to the auxiliary valve 40. After being throttled and depressurized by the auxiliary valve 40, it will enter the gas supply port 12 of the compressor 10. This corresponds to the mode in which the second heat exchange unit 220 operates as the defrosting side.

[0067] By controlling the switching states of the second three-way valve 50 and the third three-way valve 60 respectively, it is possible to independently set whether the heat exchange unit connected to the first pipeline 211 and the second pipeline 221 performs conventional heating and evaporation followed by gas return, or performs defrosting and heat release followed by gas replenishment.

[0068] In some embodiments, combined with Figure 1 The first pipeline 211 includes a first main pipe 2111, multiple first branch pipes 2112, and a first main valve 2113. The first main pipe 2111 is connected to the outlet of the first valve. There are multiple first branch pipes 2112, each passing through a first fin and connected to the first main pipe 2111. The multiple first branch pipes 2112 converge and connect to the inlet of the second valve. The first main valve 2113 is located on the first main pipe 2111, and its opening is adjustable.

[0069] Specifically, the first main pipe 2111 is connected to the inlet end of each first branch pipe 2112 through a distributor head or a branch pipe, distributing the refrigerant from the first main pipe 2111 to each first branch pipe 2112. After the outlet ends of all the first branch pipes 2112 converge, they are connected to the second valve inlet of the second three-way valve 50.

[0070] The first main valve 2113 is disposed on the first main pipe 2111, and the opening degree of the first main valve 2113 is adjustable. The first main valve 2113 is a throttling device, such as an electronic expansion valve or a thermostatic expansion valve. By adjusting the opening degree of the first main valve 2113, the flow rate of refrigerant flowing from the first main pipe 2111 into multiple first branch pipes 2112 can be controlled, and the refrigerant can be throttled and depressurized, changing it from a high-pressure liquid state to a low-pressure two-phase state suitable for evaporation and heat absorption in the first branch pipes 2112.

[0071] For the second conduit 221, similar to the first conduit 211, in some embodiments, it is combined with... Figure 1 The second pipeline 221 includes a second main pipe 2211, multiple second branch pipes 2212, and a second main valve 2213. The second main pipe 2211 is connected to the outlet of the second valve. Multiple second branch pipes 2212 are installed through the second fins and connected to the second main pipe 2211. The multiple second branch pipes 2212 converge and connect to the inlet of the third valve. The second main valve 2213 is located on the second main pipe 2211, and its opening is adjustable.

[0072] By setting an independent and adjustable main valve on each main pipeline, the refrigerant entering the first heat exchange unit 210 and the second heat exchange unit 220 can be independently regulated and throttled. In the heating-without-defrosting mode, the first main valve 2113 and the second main valve 2213 can adjust their openings according to the heat exchange requirements on both sides, optimizing refrigerant distribution and evaporation temperature.

[0073] In the heating defrosting mode, for example when the first heat exchange unit 210 needs to defrost, the first main valve 2113 can be opened wide or even fully open to reduce the throttling effect, so that the high-temperature refrigerant can enter the first branch pipe 2112 at a higher pressure and temperature, thereby releasing heat for defrosting; at the same time, the second main valve 2213 maintains an appropriate throttling opening according to the heating demand to ensure that the refrigerant in the second branch pipe 2212 effectively evaporates and absorbs heat.

[0074] It is evident that this independent valve control, combined with the allocation of the first three-way valve 30 and the flow direction switching of the second three-way valve 50 and the third three-way valve 60, realizes a multi-level and refined refrigerant flow path for the system, and enables control of multiple operating modes.

[0075] In some embodiments, combined with Figure 1 The heat pump system also includes a water-side heat exchanger 70, which is located between the exhaust port 11 and the inlet of the first valve.

[0076] During operation, the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 10's exhaust port 11 first enters the water-side heat exchanger 70. Inside the water-side heat exchanger 70, the high-temperature refrigerant transfers heat to the cooler heat transfer medium (such as water) flowing through the heat transfer medium channel, thereby cooling the refrigerant and condensing it into a high-pressure liquid. The heat transfer medium absorbs heat, its temperature rises, and it can be delivered to the user end for heating or providing hot water. After completing condensation and releasing heat, the high-pressure liquid refrigerant flows out from the refrigerant channel outlet of the water-side heat exchanger 70 and enters the first valve inlet of the downstream first three-way valve 30.

[0077] The water-side heat exchanger 70 is located between the compressor 10 discharge port 11 and the first three-way valve 30, ensuring that all high-temperature refrigerant discharged from the compressor 10 flows through the water-side heat exchanger 70 first, regardless of whether the system is operating in normal heating mode, defrosting mode or ultra-low temperature mode. This ensures that the system can continuously output heat to the user in any operating mode, thus achieving continuous heating.

[0078] In some embodiments, combined with Figure 1 The auxiliary valve 40 is also connected to the pipeline between the exhaust port 11 and the inlet of the first valve.

[0079] This connection method allows the auxiliary valve 40 to form a branch from the high-pressure side of the main cycle to the gas injection port 12 of the compressor 10. In operating modes requiring the gas injection enthalpy enhancement function, the solenoid valve connected to this branch can be opened. At this time, part of the high-pressure liquid refrigerant condensed in the main cycle by the water-side heat exchanger 70 continues to flow to the first three-way valve 30 to enter the main evaporation cycle, while the other part flows to the auxiliary valve 40 through this branch. When this portion of the refrigerant flows through the auxiliary valve 40, it is throttled and depressurized, becoming a low-temperature, low-pressure gas-liquid two-phase fluid.

[0080] Subsequently, the two-phase fluid enters the economizer or intermediate heat exchanger, where it exchanges heat with the high-pressure liquid refrigerant from the main cycle flowing towards the main throttling device. After absorbing heat, it completely evaporates into a gas, simultaneously subcooling the main cycle liquid refrigerant. Finally, the evaporated medium-pressure gaseous refrigerant enters the medium-pressure chamber of the compressor 10 from the gas injection port 12, completing the gas injection and enthalpy increase process.

[0081] In some embodiments, combined with Figure 1 The heat pump system also includes a heat exchange device 80, which can be an economizer. The heat exchange device 80 has a first heat exchange channel and a second heat exchange channel. The two ends of the first heat exchange channel are respectively connected to the pipeline between the water-side heat exchanger 70 and the inlet of the first valve, and the two ends of the second heat exchange channel are respectively connected to the pipeline between the auxiliary valve 40 and the air supply port 12.

[0082] Specifically, the high-pressure liquid refrigerant flowing from the water-side heat exchanger 70 first flows into the first heat exchange channel of the heat exchange device 80 before entering the first three-way valve 30. While flowing in the first heat exchange channel, the refrigerant exchanges heat with the lower-temperature refrigerant flowing through the second heat exchange channel, thus being further cooled and becoming a high-pressure liquid refrigerant with a higher degree of subcooling. After being subcooled, the liquid refrigerant flows out of the first heat exchange channel and then flows to the first valve inlet of the first three-way valve 30.

[0083] The second heat exchange channel has two ends: the first end is connected to the outlet of the auxiliary valve 40, and the second end is connected to the gas supply port 12 of the compressor 10. The low-temperature, low-pressure gas-liquid two-phase refrigerant flowing from the auxiliary valve 40, after being throttled and depressurized, enters the second heat exchange channel of the heat exchange device 80. While flowing within the second heat exchange channel, this low-temperature two-phase refrigerant absorbs heat from the high-pressure refrigerant flowing through the first heat exchange channel, thereby evaporating into a gas, while its own temperature and superheat increase. The evaporated and superheated gaseous refrigerant flows out of the second heat exchange channel and then enters the gas supply port 12 of the compressor 10.

[0084] By setting up the heat exchange device 80, the high-pressure liquid refrigerant in the main circuit is subcooled, which improves the energy efficiency of the main cycle and the refrigerant utilization efficiency; it also makes the refrigerant in the make-up gas circuit evaporate and be appropriately superheated, ensuring that it enters the compressor 10 make-up gas port 12 in a pure gas phase state.

[0085] In some embodiments, combined with Figure 1 The heat pump system also includes a first control valve 90, which is located on the pipeline between the auxiliary valve 40 and the upstream side of the first valve inlet.

[0086] The first control valve 90 controls the opening and closing of the refrigerant branch flowing from the high-pressure side of the main cycle to the auxiliary valve 40. When the first control valve 90 is closed, this branch is cut off, and the refrigerant on the high-pressure side of the main cycle cannot flow to the auxiliary valve 40 through this path. When the first control valve 90 is open, a portion of the high-pressure liquid refrigerant is allowed to flow from the main circuit, through this branch, and to the inlet of the auxiliary valve 40. When enthalpy boosting is required, the first control valve 90 can be opened, and a portion of the high-pressure liquid refrigerant flows from the main circuit, through the auxiliary valve 40 and the economizer, and finally into the gas injection port 12 of the compressor 10.

[0087] In some embodiments, combined with Figure 1 An auxiliary flow path 230 is connected between the first pipe 211 and the second pipe 221, and a second control valve 231 is provided on the auxiliary flow path 230. Optionally, the auxiliary flow path 230 is connected between the outlet of the first main pipe 2111 and the outlet of the second main pipe 2211. Optionally, two second control valves 231 are provided.

[0088] In the ultra-low temperature heating defrosting mode, assuming the first pipe 211 defrosts, more refrigerant can be supplied to the second pipe 221 through the auxiliary flow path 230. In addition to adjusting the total distribution ratio through the first three-way valve 30, opening the second control valve 231 can allow some of the refrigerant that should flow to the defrosting side inlet and has a higher pressure to be directly supplemented to the heating side inlet through the auxiliary flow path 230, which can increase the refrigerant flow on the heating side. It can be seen that the auxiliary flow path 230 provides an additional controllable fluid channel, increasing the flexibility of refrigerant flow distribution within the system.

[0089] In some embodiments, combined with Figure 1 The heat pump system includes a heating mode. In heating mode, the first pipe 211 is connected to the outlet of the first valve, and the second pipe 221 is connected to the outlet of the second valve. The opening degrees of the first main valve 2113 and the second main valve 2213 are at a first preset opening value.

[0090] In this configuration, the system operates a parallel heating cycle with two evaporators 20. The high-temperature, high-pressure gaseous refrigerant discharged from the compressor 10 first condenses and releases heat in the water-side heat exchanger 70, heating the heat transfer medium. The condensed high-pressure liquid refrigerant flows into the first three-way valve 30 and is divided into two paths, entering the first main pipe 2111 and the second main pipe 2211 respectively. The two refrigerants are throttled by the first main valve 2113 and the second main valve 2213 respectively, becoming a low-temperature, low-pressure gas-liquid two-phase mixture, and then entering the first branch pipe 2112 and the second branch pipe 2212 respectively.

[0091] In the first branch pipe 2112 and the second branch pipe 2212, the refrigerant absorbs heat from the air flowing through the staggered first and second fins and evaporates into a low-temperature, low-pressure gas. The evaporated gaseous refrigerant flows together and is guided through the second three-way valve 50 and the third three-way valve 60 to the liquid return port 13 of the compressor 10, where it is drawn into the compressor 10 to complete the complete heating cycle.

[0092] In some embodiments, combined with Figure 1 The heat pump system includes a heating and defrosting mode. In the heating and defrosting mode, the first pipe 211 is connected to the outlet of the first valve, and the second pipe 221 is connected to the outlet of the second valve. The main valve corresponding to the unit to be defrosted in the first heat exchange unit 210 and the second heat exchange unit 220 is at a first preset opening value, and the main valve corresponding to the unit providing defrosting and heating is at a second preset opening value, which is greater than the first preset opening value.

[0093] Assuming that in the current heating and defrosting mode, the first heat exchange unit 210 is the one to be defrosted, and the second heat exchange unit 220 continues to provide heating, the opening of the first main valve 2113 corresponding to the first heat exchange unit 210 is adjusted to a preset second preset opening value. The second preset opening value is a large opening, greater than the first preset opening value in the normal heating mode, and can even be set to be fully open.

[0094] In heating defrosting mode, for the heat exchange unit to be defrosted (such as the first heat exchange unit 210), its second three-way valve 50 is switched so that its inlet is connected to the outlet leading to the auxiliary valve 40. For the second heat exchange unit 220 for defrosting and heating, the inlet of its third three-way valve 60 is connected to the outlet leading to the liquid return port 13 of the compressor 10. At this time, the first control valve 90 is normally closed to prevent high-pressure main circuit refrigerant from entering the auxiliary valve 40 and interfering.

[0095] Thus, a portion of the refrigerant flowing to the first pipe 211 to be defrosted, due to the large opening of the first main valve 2113 and the weak throttling effect, enters the first branch pipe 2112 at a higher pressure and temperature. As this relatively hot refrigerant flows in the first branch pipe 2112, it releases heat to the frosted first fins and pipes, melting the frost and cooling itself. The refrigerant, after defrosting and releasing heat, flows through the second three-way valve 50 to the auxiliary valve 40 and the economizer. After being throttled and depressurized by the auxiliary valve 40 and the economizer, it can be used as a makeup gas source to enter the compressor 10's makeup gas port 12. By increasing the opening of the main valve on the defrosting side, its throttling degree is reduced, allowing more heat to be used for defrosting.

[0096] In some embodiments, combined with Figure 1The heat pump system includes an ultra-low temperature heating and defrosting mode. In this mode, the first pipe 211 is connected to the outlet of the first valve, and the second pipe 221 is connected to the outlet of the second valve. The main valve of the unit to be defrosted in the first heat exchange unit 210 and the second heat exchange unit 220 is at a first preset opening value, while the main valve of the unit supplying heat during defrosting is at a second preset opening value, which is greater than the first preset opening value. An auxiliary flow path 230 connects the first pipe 211 and the second pipe 221, and the control valve of the auxiliary flow path 230 is open.

[0097] The ultra-low temperature heating defrosting mode can be understood as activating an auxiliary flow path 230 on top of the conventional heating defrosting mode. While maintaining the aforementioned heating defrosting flow path, the system can open the solenoid valve on the auxiliary flow path 230. When this solenoid valve opens, a portion of the refrigerant allocated from the first three-way valve 30, which was originally intended to flow entirely to the first pipe 211, is diverted through this solenoid valve into the second pipe 221 on the heating side. This increases the refrigerant mass flow rate participating in the evaporation and heat absorption in the second pipe 221 on the heating side under ultra-low temperature conditions. Thus, with the same heat exchange area and temperature difference, increasing the refrigerant flow rate increases the total heat absorption. This adjustment helps compensate for the decrease in evaporation temperature and the reduction in heat absorption per kilogram of refrigerant caused by the ultra-low temperature environment, maintaining the system's heating capacity in harsh environments.

[0098] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A heat pump system, characterized in that, include: The compressor (10) includes an exhaust port (11), an air inlet (12), and a liquid return port (13). The evaporator (20) includes a first heat exchange unit (210) and a second heat exchange unit (220). The first heat exchange unit (210) includes a plurality of first fins and a first pipe (211) passing through the first fins. The second heat exchange unit (220) includes a plurality of second fins and a second pipe (221) passing through the second fins. The first fins and the second fins are arranged in an alternating layered configuration. The first three-way valve (30) is connected to the exhaust port (11), the first pipeline (211) and the second pipeline (221) respectively; Auxiliary valve (40) is connected to the air supply port (12); The second three-way valve (50) connects the first pipeline (211) to the auxiliary valve (40) and the return port (13) respectively through the second three-way valve (50); The third three-way valve (60) and the second pipeline (221) are connected to the auxiliary valve (40) and the return port (13) respectively through the third three-way valve (60).

2. The heat pump system according to claim 1, characterized in that, The first three-way valve (30) includes a first valve inlet, a first valve outlet and a second valve outlet. The first valve inlet is connected to the exhaust port (11), the first valve outlet is connected to the first pipeline (211), and the second valve outlet is connected to the second pipeline (221).

3. The heat pump system according to claim 2, characterized in that, The second three-way valve (50) includes: a second valve inlet, a third valve outlet, and a fourth valve outlet; The inlet of the second valve is connected to the first pipeline (211); The outlet of the third valve is connected to the auxiliary valve (40); The outlet of the fourth valve is connected to the return port (13).

4. The heat pump system according to claim 2, characterized in that, The third three-way valve (60) includes: a third valve inlet, a fifth valve outlet, and a sixth valve outlet; The inlet of the third valve is connected to the second pipeline (221); The outlet of the fifth valve is connected to the auxiliary valve (40); The outlet of the sixth valve is connected to the return port (13).

5. The heat pump system according to claim 3, characterized in that, The first conduit (211) includes: The first main pipe (2111) is connected to the outlet of the first valve; The first branch pipe (2112) is multiple, and the multiple first branch pipes (2112) are all inserted through the first fin and are all connected to the first main pipe (2111). After the multiple first branch pipes (2112) merge, they are connected to the inlet of the second valve. A first main valve (2113) is provided on the first main valve (2113), and the opening degree of the first main valve (2113) is adjustable.

6. The heat pump system according to claim 4, characterized in that, The second conduit (221) includes: The second main pipe (2211) is connected to the outlet of the second valve; The second branch pipe (2212) is multiple, and the multiple second branch pipes (2212) are all inserted through the second fin and are all connected to the second main pipe (2211). The multiple second branch pipes (2212) merge and are connected to the inlet of the third valve. A second main valve (2213) is provided on the second main valve (2213), and the opening degree of the second main valve (2213) is adjustable.

7. The heat pump system according to claim 2, characterized in that, Also includes: A water-side heat exchanger (70) is located between the exhaust port (11) and the inlet of the first valve.

8. The heat pump system according to claim 7, characterized in that, The auxiliary valve (40) is also connected to the pipeline between the exhaust port (11) and the inlet of the first valve.

9. The heat pump system according to claim 8, characterized in that, Also includes: A heat exchange device (80) having a first heat exchange channel and a second heat exchange channel; The two ends of the first heat exchange channel are respectively connected to the pipeline between the water-side heat exchanger (70) and the inlet of the first valve; The two ends of the second heat exchange channel are respectively connected to the pipeline between the auxiliary valve (40) and the air supply port (12).

10. The heat pump system according to claim 8, characterized in that, Also includes: The first control valve (90) is located on the pipeline between the auxiliary valve (40) and the upstream side of the inlet of the first valve.

11. The heat pump system according to claim 1, characterized in that, An auxiliary flow path (230) is connected between the first pipeline (211) and the second pipeline (221), and a second control valve (231) is provided on the auxiliary flow path (230).

12. The heat pump system according to claim 2, characterized in that, The heat pump system includes a heating mode, in which the first pipe (211) is connected to the outlet of the first valve, and the second pipe (221) is connected to the outlet of the second valve. The opening degree of the first main valve (2113) and the second main valve (2213) is at the first preset opening degree value.

13. The heat pump system according to claim 2, characterized in that, The heat pump system includes a heating and defrosting mode, in which the first pipe (211) is connected to the outlet of the first valve, and the second pipe (221) is connected to the outlet of the second valve. In the first heat exchange unit (210) and the second heat exchange unit (220), the opening degree of the main valve corresponding to the one to be defrosted is at a first preset opening degree value, and the opening degree of the main valve corresponding to the one to be defrosted and supplied with heat is at a second preset opening degree value, which is greater than the first preset opening degree value.

14. The heat pump system according to claim 2, characterized in that, The heat pump system includes an ultra-low temperature heating and defrosting mode. In the ultra-low temperature heating and defrosting mode, the first pipe (211) is connected to the outlet of the first valve, and the second pipe (221) is connected to the outlet of the second valve. In the first heat exchange unit (210) and the second heat exchange unit (220), the opening degree of the main valve corresponding to the one to be defrosted is at a first preset opening degree value, and the opening degree of the main valve corresponding to the one to be defrosted and supplied with heat is at a second preset opening degree value, and the second preset opening degree value is greater than the first preset opening degree value. An auxiliary flow path (230) is connected between the first pipeline (211) and the second pipeline (221), and the control valve of the auxiliary flow path (230) is open.

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