Jet synergistic type enhanced vapor injection efficient heat pump system and regulation and control method thereof

Abstract

The invention provides a jet synergy type enhanced vapor injection efficient heat pump system and a regulation and control method thereof.The system is composed of a heat pump subsystem and an active enhanced vapor injection subsystem, and the heat pump subsystem comprises a compressor, a condenser, an evaporator and a main electronic expansion valve; the system comprises an enhanced vapor injection electronic expansion valve, a heat exchanger, an external heat source and an ejector. Part of refrigerant of the heat pump liquid pipe section is introduced into the active enhanced vapor injection heat exchanger to absorb heat of an external heat source and convert the heat into heating capacity, and the heat pump performance is greatly improved. An ejector is designed in the system, a low-pressure low-temperature refrigerant of an ejection air return pipe section exchanges heat with an ejection refrigerant in the ejector, and the other heat exchange mode is that the ejection refrigerant exchanges heat with the ejection refrigerant in a first economizer, so that the temperature of the ejection refrigerant is reduced, and the temperature difference between the ejection refrigerant and an external heat source is increased to absorb more heat of the external heat source; and the enhanced vapor injection effect is enhanced.

Description

Technical Field

[0001] This invention relates to the field of heat pump system technology, and more specifically, to a jet-enhanced high-efficiency heat pump system with jet enthalpy enhancement and its control method. Background Technology

[0002] Driven by clean energy technologies, air source heat pump systems have become one of the core solutions for residential heating, industrial heating, and other fields, and their application in winter heating in cold regions is becoming increasingly widespread.

[0003] However, there is at least one of the following problems in the relevant technologies: In traditional technologies, the heat pump system has a reduced heat absorption capacity of the evaporator in low-temperature environments, which leads to insufficient air intake of the compressor and a decrease in heating capacity, resulting in insufficient heating capacity and failure to meet the heating needs of the terminal. Summary of the Invention

[0004] The technical problem solved by this invention is that in traditional heat pump systems, the evaporator's heat absorption capacity decreases in low-temperature environments, resulting in insufficient compressor intake and reduced heating capacity, which in turn leads to insufficient heating capacity and fails to meet the heating needs of the terminal.

[0005] To address the aforementioned problems, this invention provides a high-efficiency heat pump system with jet-enhanced enthalpy, comprising: a heat pump subsystem and an active jet-enhanced enthalpy subsystem; the heat pump subsystem includes a compressor, a condenser, an evaporator, and a main electronic expansion valve; the active jet-enhanced enthalpy subsystem includes: a jet-enhanced enthalpy electronic expansion valve, an external heat source, and an ejector; the compressor is equipped with an intermediate jet port; the condenser outlet pipe is split into a first branch and a second branch; the refrigerant in the first branch enters the evaporator after being throttled by the main electronic expansion valve; an ejector branch branches off from the evaporator outlet, serving as the ejector flow and connecting to the low-pressure ejector fluid inlet of the ejector; the refrigerant in the second branch, after being throttled by the jet-enhanced enthalpy electronic expansion valve, serves as the driving flow and connects to the high-pressure driving fluid inlet of the ejector; the ejector outlet connects to the intermediate jet port, allowing the mixed fluid formed by the mixing of the ejector flow and the driving flow within the ejector to return to the compressor.

[0006] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: This invention introduces an ejector as the energy recovery hub of the system; the condenser outlet is divided into two branches, the first branch is connected to the evaporator to form an entrained flow, and the fluid in the second branch is throttled by the jet enthalpy-increasing electronic expansion valve to form a driving flow; the driving flow expands in the ejector to actively entrain the low-pressure entrained flow, and the two mix in the ejector and are pressurized through the diffuser section to form a medium-pressure mixed gas that returns to the compressor's intermediate cavity to replenish the compressor; by strengthening the entrainment and mixing process, the system can maintain a high evaporation pressure in a low-temperature environment, fundamentally solving the problem of reduced heating capacity caused by insufficient heat absorption by the evaporator in traditional air source heat pumps.

[0007] In one embodiment of the invention, at least one subcooler is provided in the passage between the throttling of the jet enthalpy-increasing electronic expansion valve and the intermediate jet port, for exchanging heat between the refrigerant flowing through it and an external heat source.

[0008] Compared with existing technologies, the technical effects achieved by this solution are as follows: Based on the energy recovery achieved by introducing an ejector, the circulating refrigerant is further cooled by setting up a subcooler, resulting in a synergistic effect: By actively reducing the temperature of the refrigerant flowing through it using an external heat source, the heat exchange temperature difference between the refrigerant and the external heat source is significantly increased, thereby greatly improving the system's heat absorption capacity in low-temperature environments.

[0009] In one embodiment of the invention, the subcooler includes a first active vapor injection enthalpy booster economizer, which is disposed on a pipeline between the vapor injection enthalpy booster electronic expansion valve and the receiving chamber of the injector.

[0010] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: The first active jet enthalpy enhancer is clearly positioned between the jet enthalpy enhancer electronic expansion valve and the injector receiving chamber, so that the drive flow exchanges heat with an external heat source before entering the injector. For example, it absorbs heat from the external heat source, directly increasing the enthalpy value of the drive flow, enhancing the ejection capability of the injector and the energy of the mixed fluid; and it reduces the energy loss of the drive flow before injection, further alleviating the problem of heating capacity decay at low temperatures.

[0011] In one embodiment of the present invention, a first economizer is provided between the jet enthalpy-enhancing electronic expansion valve and the first active jet enthalpy-enhancing economizer; the ejector branch is connected to the injector through the first economizer; the first economizer and the first active jet enthalpy-enhancing economizer are connected in series.

[0012] Compared with existing technologies, the technical effects achieved by this solution are as follows: A first economizer is added and connected to the ejector branch. The low-temperature refrigerant in the ejector branch is used to subcool the drive flow in the second branch, significantly improving the subcooling degree of the drive flow, reducing throttling losses, and increasing the cooling capacity per unit mass of the drive flow. Furthermore, the first economizer is connected in series with the first active jet enthalpy-enhancing economizer, achieving a dual effect of low-temperature subcooling of the ejector flow plus heat exchange from an external heat source. This results in a more significant increase in heating capacity when the fluid mixed by the ejector is supplied to the compressor. Finally, the low-temperature energy of the ejector flow is fully recovered, improving the system's energy utilization rate and solving the problem of low energy efficiency caused by energy waste in traditional technologies.

[0013] In one embodiment of the present invention, the subcooler includes a second active jet enthalpy booster, which is disposed on the pipeline between the outlet of the injector and the intermediate jet port.

[0014] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: Compared with the above example, by installing a second active jet enthalpy booster on the pipeline between the injector outlet and the intermediate jet port, the mixed gas about to enter the compressor is cooled, which can further reduce the compressor's intake and exhaust temperatures. This is particularly beneficial for coping with ultra-high load conditions, providing more effective protection for the compressor, and can also absorb heat from external heat sources to increase the system's heating capacity.

[0015] In one embodiment of the present invention, a control method for a high-efficiency heat pump system with vapor injection enthalpy enhancement is also provided, which can be applied to any of the above-mentioned high-efficiency heat pump systems with vapor injection enthalpy enhancement. The control method includes: responding to a heating command, detecting the operating parameters of the high-efficiency heat pump system with vapor injection enthalpy enhancement and determining whether the heating start-up conditions are met; if the heating start-up conditions are met, controlling the heat pump unit to perform heating, and adjusting the operating rate of the compressor according to the preset return water temperature; after the heat pump unit has been running for a first time, determining whether the high-efficiency heat pump system with vapor injection enthalpy enhancement meets the vapor injection enthalpy enhancement conditions; if so, activating the vapor injection enthalpy enhancement function, and synchronously adjusting the opening degrees of the main electronic expansion valve and the vapor injection enthalpy enhancement electronic expansion valve based on the intake superheat and injection superheat during the vapor injection enthalpy enhancement process.

[0016] Compared with existing technologies, the technical effects achieved by this solution are as follows: Based on the process of heating command, detecting start-up conditions, adjusting compressor frequency, judging jet enthalpy conditions, and coordinating valve adjustment, the system achieves dynamic control of the entire process from start-up to jet enthalpy enhancement, ensuring the reliability of heating start-up at low temperatures; adjusting the compressor frequency according to the preset return water temperature ensures that the output heat matches the demand, avoiding energy waste; delaying the judgment of jet enthalpy enhancement conditions ensures that the system is stable before activating the efficiency enhancement function, reducing losses from frequent start-stop cycles; and, based on the synchronous adjustment of the main electronic expansion valve and the jet enthalpy enhancement electronic expansion valve according to the intake superheat and injection superheat, the parameter imbalance problem caused by traditional single valve adjustment is solved, improving the stability of the jet enthalpy enhancement process.

[0017] In one embodiment of the present invention, the jet enthalpy enhancement function is activated, and the opening degrees of the main electronic expansion valve and the jet enthalpy enhancement electronic expansion valve are synchronously adjusted based on the intake superheat and injection superheat during the jet enthalpy enhancement process. This includes: opening the jet enthalpy enhancement electronic expansion valve to its initial opening degree; acquiring a first temperature detected by the refrigerant temperature sensor at the outlet of the external heat source heat exchanger, and a second temperature detected by the outlet temperature sensor of the jet enthalpy enhancement electronic expansion valve; calculating the actual injection superheat based on the first and second temperatures, wherein the actual injection superheat is defined as the difference between the first and second temperatures; and adjusting the opening degree of the jet enthalpy enhancement electronic expansion valve based on the actual injection superheat.

[0018] Compared with existing technologies, the technical effects achieved by this solution are as follows: It clarifies the detection methods for the first temperature at the outlet of the external heat source heat exchanger and the second temperature at the outlet of the jet enthalpy-enhancing electronic expansion valve, as well as the calculation methods for the actual jet superheat, providing a quantitative basis for the adjustment of the jet enthalpy-enhancing electronic expansion valve; it dynamically adjusts the valve opening based on the actual superheat, increasing the opening if the superheat is too high, reducing the driving flow temperature, ensuring the driving flow is in the optimal jet state, improving the ejector's induction efficiency and the quality of the mixed fluid, and solving the problem of jet parameter runaway at low temperatures.

[0019] In one embodiment of the present invention, the jet enthalpy enhancement function is activated, and the openings of the main electronic expansion valve and the jet enthalpy enhancement electronic expansion valve are synchronously adjusted based on the intake superheat and injection superheat during the jet enthalpy enhancement process. The method further includes: adjusting the flow control valve according to temperature sensors, specifically: acquiring a third temperature detected by an external heat source inlet medium temperature sensor and a fourth temperature detected by an external heat source outlet medium temperature sensor; when the third temperature is less than the sum of the first temperature and the first temperature hysteresis value, but greater than the first temperature, controlling the flow control valve to open to inject cryogenic refrigerant; or, when the fourth temperature is less than the second temperature and the second temperature hysteresis value, but greater than the second temperature, opening the flow control valve to inject cryogenic refrigerant.

[0020] Compared with existing technologies, the technical effects achieved by this solution are as follows: Based on the difference between the third temperature detected at the inlet of the external heat source and the fourth temperature detected at the outlet of the external heat source and the first and second temperatures, the opening timing of the flow regulating valve is precisely controlled, so that the low-temperature energy of the ejector flow matches the heat exchange demand of the external heat source; ensuring that the ejector flow participates in heat exchange under the most suitable operating conditions, such as opening when the external heat source temperature is slightly higher than the ejector flow, maximizing the subcooling effect of the first economizer and the heat absorption efficiency of the external heat source heat exchanger, and solving the problem of energy waste caused by improper heat exchange timing in traditional technologies.

[0021] In one embodiment of the present invention, the jet enthalpy enhancement function is activated, and the openings of the main electronic expansion valve and the jet enthalpy enhancement electronic expansion valve are synchronously adjusted based on the suction superheat and injection superheat during the jet enthalpy enhancement process. The method further includes: acquiring the temperature detected by the suction temperature sensor and recording it as the fifth temperature; acquiring the temperature detected by the outdoor heat exchanger coil temperature sensor and recording it as the sixth temperature; adjusting the opening of the main electronic expansion valve according to the suction superheat of the evaporator; the suction superheat is defined as the difference between the fifth temperature and the sixth temperature.

[0022] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: the opening of the main electronic expansion valve is adjusted synchronously according to the suction superheat to ensure that the refrigerant in the evaporator is in the optimal evaporation state; the problem of low jet energy caused by insufficient heat absorption of the evaporator is avoided, providing a stable low-temperature jet for the ejector, and working in synergy with the adjustment of the jet enthalpy-increasing electronic expansion valve to further improve the system's heat absorption capacity and heating stability at low temperatures.

[0023] In one embodiment of the present invention, the control method further includes: detecting the jet enthalpy-enhancing high-efficiency heat pump system; when the jet enthalpy-enhancing high-efficiency heat pump system meets the preset stop conditions, the jet enthalpy enhancement stops and the jet enthalpy-enhancing electronic expansion valve is closed; the preset active jet enthalpy-enhancing stop conditions include: the ambient temperature is greater than the preset ambient temperature; the first temperature is less than the sum of the second temperature and the second temperature hysteresis value; or, the fourth temperature is less than the sum of the third temperature and the third temperature hysteresis value.

[0024] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: three types of shutdown conditions are clearly defined: ambient temperature is too high, the difference between the first and second temperatures is abnormal, and the difference between the fourth and third temperatures is abnormal, ensuring that the jet enthalpy enhancement function is shut down in time under unsuitable operating conditions, thus avoiding ineffective energy consumption.

[0025] By adopting the technical solution of the present invention, the following technical effects can be achieved: (1) The present invention introduces an ejector as the energy recovery hub of the system; the condenser outlet is divided into two branches. The first branch is connected to the evaporator to form an ejector flow. The fluid in the second branch is throttled by the jet enthalpy-increasing electronic expansion valve to form a driving flow. The driving flow expands in the ejector to actively eject the low-pressure ejector flow. The two are mixed in the ejector and pressurized through the diffuser section to form a medium-pressure mixed gas that returns to the intermediate cavity of the compressor to replenish the compressor. By strengthening the ejection and mixing process, the system can maintain a high evaporation pressure in a low-temperature environment, which fundamentally solves the problem of heat capacity reduction caused by insufficient heat absorption of the evaporator in traditional air source heat pumps. (2) The present invention adds a first economizer and connects it to the ejector branch. The low temperature refrigerant of the ejector branch is used to subcool the driving flow of the second branch, which significantly improves the subcooling degree of the driving flow, reduces throttling losses, and increases the unit mass cooling capacity of the driving flow. On this basis, the first economizer is connected in series with the first active jet enthalpy-increasing economizer to achieve the dual effect of low temperature subcooling of the ejector flow and heat exchange with external heat source, so that when the fluid mixed by the ejector is supplemented to the compressor, the heating capacity is significantly improved. The low temperature energy of the ejector flow is fully recovered, the system energy utilization rate is improved, and the problem of low energy efficiency caused by energy waste in traditional technology is solved. (3) By installing a second active jet enthalpy booster on the pipeline between the outlet of the injector and the intermediate jet port, the present invention cools the mixed gas that is about to enter the compressor, which can further reduce the intake temperature and exhaust temperature of the compressor. This is particularly beneficial for dealing with ultra-high load conditions, providing more effective protection for the compressor, and can also absorb heat from external heat sources to increase the system's heating capacity. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a schematic diagram of a jet-enhanced high-efficiency heat pump system with jet enthalpy enhancement provided in the first embodiment of the present invention; Figure 2 This is a schematic diagram of a jet-enhanced high-efficiency heat pump system with jet enthalpy enhancement provided in the second embodiment of the present invention; Figure 3 The flowchart illustrates a control method for a jet-induced enthalpy-enhanced high-efficiency heat pump system provided by this invention.

[0027] Explanation of reference numerals in the attached figures: 1. Compressor; 10. Low-pressure switch; 11. Gas-liquid separator; 101. First economizer; 102. First active vapor injection enthalpy-enhancing economizer; 103. Refrigerant inlet pipe of external heat source heat exchanger; 104. High-pressure inlet pipe of ejector; 105. Low-pressure fluid inlet pipe of ejector; 106. Refrigerant outlet pipe of ejector; 107. Second active vapor injection enthalpy-enhancing economizer; 12. Oil return capillary tube; 2. High-pressure switch; 205. Flow regulating valve; 21. Water pump; 3. Oil separator; 31. Discharge temperature sensor; 32. Outdoor ambient temperature sensor; 33. Outdoor heat exchanger coil temperature sensor; 34. Suction valve; Temperature sensor; 35. Return water temperature sensor; 36. Outlet water temperature sensor; 37. Condenser outlet refrigerant temperature sensor; 38. Vacuum enthalpy-increasing electronic expansion valve outlet temperature sensor; 39. External heat source heat exchanger inlet refrigerant temperature sensor; 4. Four-way valve; 40. External heat source heat exchanger outlet refrigerant temperature sensor; 41. External heat source inlet medium temperature sensor; 42. External heat source outlet medium temperature sensor; 5. Ejector; 6. Condenser; 61. Compressor exhaust pipe; 62. Condenser liquid outlet pipe; 81. Main electronic expansion valve; 82. Vacuum enthalpy-increasing electronic expansion valve; 9. Evaporator. Detailed Implementation

[0028] To facilitate understanding of this solution, the existing technology is further described below; the conventional active vapor injection enthalpy-enhancing operation is as follows: the high-pressure liquid refrigerant flowing out of the condenser first enters the economizer and is then divided into two paths; the refrigerant in the main path is depressurized by the main throttle valve and enters the evaporator to absorb heat, becoming low-temperature, low-pressure vapor before returning to the compressor's main suction port; while the enthalpy-enhancing branch separates medium-temperature, medium-pressure gaseous refrigerant from the economizer, and this gaseous refrigerant is directly transported to the compressor's intermediate gas injection port through a pipeline; the refrigerant in the main path and the refrigerant in the enthalpy-enhancing branch do not mix with other fluids throughout the entire process.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] [First Embodiment] Please see Figure 1 , Figure 1 This is a schematic diagram of a jet-enhanced enthalpy-increasing high-efficiency heat pump system according to the first embodiment of the present invention. The jet-enhanced enthalpy-increasing high-efficiency heat pump system includes a heat pump subsystem and an active jet-enhanced enthalpy-increasing subsystem. The heat pump subsystem includes a compressor 1, a condenser 6, an evaporator 9, and a main electronic expansion valve 81. The active jet-enhanced enthalpy-increasing subsystem includes a jet-enhanced enthalpy-increasing electronic expansion valve 82, an ejector 5, and an external heat source. The compressor 1 is provided with an intermediate jet port. The outlet pipe of the condenser 6 is split into a first branch and a second branch. The refrigerant in the first branch enters the evaporator 9 after being throttled by the main electronic expansion valve 81. Then, an ejector branch is split from the outlet of the evaporator 9 and connected to the low-pressure ejector fluid inlet of the ejector 5 as an ejector flow. The refrigerant in the second branch is throttled by the jet-enhanced enthalpy-increasing electronic expansion valve 82 and connected to the high-pressure drive fluid inlet of the ejector 5 as a drive flow. The outlet of the ejector 5 is connected to the intermediate jet port and outputs a mixed fluid formed by the ejector flow and the drive flow to the compressor 1.

[0031] Furthermore, at least one subcooler is provided in the passage between the throttling of the jet enthalpy-increasing electronic expansion valve 82 and the intermediate jet port, for exchanging heat between the refrigerant flowing through it and an external heat source.

[0032] Furthermore, the subcooler includes a first active vapor enthalpy booster economizer 102, which is disposed on the pipeline between the vapor enthalpy booster electronic expansion valve 82 and the receiving chamber of the injector 5.

[0033] Furthermore, a first economizer 101 is provided between the jet enthalpy-enhancing electronic expansion valve 82 and the first active jet enthalpy-enhancing economizer 102; the ejector branch is connected to the injector 5 through the first economizer 101; the first economizer 101 and the first active jet enthalpy-enhancing economizer 102 are connected in series.

[0034] Furthermore, the jet-induced enthalpy-enhanced high-efficiency heat pump system also includes: an oil separator 3, a gas-liquid separator 11, and a four-way valve 4; the oil separator 3 is connected to the output end of the compressor 1; the four-way valve 4 is connected to at least the oil separator 3, the condenser 6, and the evaporator 9; one end of the gas-liquid separator 11 is connected to the four-way valve 4, and the other end is connected to the compressor 1.

[0035] Furthermore, the jet enthalpy-enhancing high-efficiency heat pump system also includes a flow regulating valve 205, which is located on the ejector branch and is used to regulate the flow rate of the ejector stream.

[0036] Furthermore, an exhaust temperature sensor 31 is provided on the connecting pipe between the compressor 1 and the oil separator 3 to detect the temperature of the gas discharged from the evaporator 9.

[0037] Based on the specific working conditions, the high-temperature and high-pressure refrigerant gas discharged from compressor 1 enters four-way valve 4 through pipe d of four-way valve 4, and then exits through pipe e of four-way valve 4. After exiting through pipe e of four-way valve 4, it enters condenser 6 along compressor exhaust pipe 61 and condenses into high-pressure room-temperature liquid. Then, it flows out of condenser 6, and the liquid refrigerant flowing out of condenser 6 is discharged along the first branch and the second branch. In the first branch, the refrigerant is throttled by the main electronic expansion valve 81 and becomes a low-temperature and low-pressure gas-liquid mixture, which then enters evaporator 9. After entering evaporator 9, it absorbs heat from the environment and evaporates into low-temperature and low-pressure vapor. After being discharged from the outlet of evaporator 9, part of it is discharged as the main circuit fluid through pipe e of four-way valve 4, and then returns to the suction port of compressor 1 after passing through three-way valve and gas-liquid separator 11. The other part is treated as an ejector flow, which enters the first economizer 101 after passing through the ejector branch and flow regulating valve 205. After exchanging heat with the refrigerant in the first economizer 101, i.e. the second branch, it enters ejector 5.

[0038] The liquid refrigerant in the second branch, after being throttled by the jet enthalpy-increasing electronic expansion valve 82, first enters the low-pressure side of the first economizer 101. Here, it is pre-cooled and absorbs heat by the lower-temperature ejector flow flowing through the low-pressure side, further reducing its temperature. Then it enters the first active jet enthalpy-increasing economizer 102, where it exchanges heat with the hot water driven by the water pump 21, i.e., the external heat source, and absorbs heat to become a subcooled or driven flow with a certain temperature. This driven fluid enters the high-pressure driven flow inlet of the ejector 5.

[0039] Finally, the ejector flow and the driving flow mix in the ejector 5 to form a mixed fluid, and the pressure is increased through the diffuser section of the ejector 5 to form a medium-pressure gas. The mixed gas returns to the intermediate pressure chamber through the intermediate jet port of the compressor 1, completing the jet enthalpy increase process. That is, in the first embodiment, the gas in the first branch is used to eject the gas in the second branch, and then the gas is mixed in the ejector 5 to form a medium-pressure gas, which is then input into the intermediate jet port of the compressor 1.

[0040] Furthermore, by adjusting the opening of the main electronic expansion valve 81 and the jet enthalpy-enhancing electronic expansion valve 82, the injection ratio and jet enthalpy value are adjusted to achieve the optimal matching of energy efficiency of the jet enthalpy-enhancing high-efficiency heat pump system.

[0041] [Second Embodiment] For further information, please refer to [link / reference]. Figure 2 , Figure 2 This is a schematic diagram of a jet-enhanced enthalpy-increasing high-efficiency heat pump system according to a second embodiment of the present invention. The present invention also provides a second embodiment; the second embodiment and the first embodiment are parallel technical solutions. The main difference between the second embodiment and the first embodiment is that only one subcooler is provided, i.e., only one second active jet enthalpy-increasing economizer 107 is provided; furthermore, the second active jet enthalpy-increasing economizer 107 in the second embodiment is identical to the first active jet enthalpy-increasing economizer 102 in the first embodiment except for its location; wherein, the first active jet enthalpy-increasing economizer 102 and the second active jet enthalpy-increasing economizer 107 are the same device; the terms "first" and "second" are only used to distinguish the active jet enthalpy-increasing economizers in different embodiments.

[0042] Specifically, the subcooler includes a second active jet enthalpy enhancer 107, which is located on the pipeline between the outlet of the injector 5 and the intermediate jet port.

[0043] Based on the specific operating conditions, the refrigerant flowing out of the second branch from the condenser 6, after being throttled by the jet enthalpy-increasing electronic expansion valve 82, becomes a low-temperature, low-pressure fluid and directly enters the ejector 5 as the driving flow; at the same time, the refrigerant in the first branch absorbs heat and evaporates in the evaporator 9 to form a low-temperature, low-pressure gas, which is directly drawn into the ejector 5 through the e-tube of the four-way valve 4; after the driving flow and the ejector flow are mixed in the ejector 5, the pressure is increased through the diffuser section of the ejector 5 to form a medium-pressure mixed gas; then the mixed gas enters the second active jet enthalpy-increasing economizer 107, exchanges heat with the external heat source, absorbs heat, and finally enters the intermediate jet port of the compressor 1.

[0044] Furthermore, a high-pressure switch 2 and an exhaust temperature sensor 31 are also provided between the compressor 1 and the oil separator 3.

[0045] Furthermore, a low-pressure switch 10 and a suction temperature sensor 34 are also provided on the pipeline between the evaporator 9 and the gas-liquid separator 11.

[0046] Furthermore, an oil return capillary tube 12 connected to the oil separator 3 is provided on the pipeline connecting the gas-liquid separator 11 and the compressor 1.

[0047] Furthermore, an outdoor heat exchanger coil temperature sensor 33 and an outdoor ambient temperature sensor 32 are respectively installed at the inlet and outlet of the evaporator 9.

[0048] Furthermore, a return water temperature sensor 35 is installed on the pipeline connecting the water pump 21 and the condenser 6.

[0049] Furthermore, an outlet water temperature sensor 36 is also installed on the pipe connected to the condenser 6.

[0050] Furthermore, a condenser outlet refrigerant temperature sensor 37 is installed on the condenser liquid outlet pipe 62, and the condenser liquid outlet pipe 62 is divided into a first branch and a second branch after passing through the condenser outlet refrigerant temperature sensor 37.

[0051] Furthermore, an outlet temperature sensor 38 for the vapor injection enthalpy-enhancing electronic expansion valve 82 is installed on the outlet pipe of the vapor injection enthalpy-enhancing electronic expansion valve 82.

[0052] Furthermore, the inlet and outlet pipes of the first active jet enthalpy enhancer 102 are respectively equipped with an external heat source heat exchanger inlet refrigerant temperature sensor 39 and an external heat source heat exchanger outlet refrigerant temperature sensor 40. Furthermore, an external heat source inlet medium temperature sensor 41 and an external heat source outlet medium temperature sensor 42 are respectively provided at the inlet and outlet ends of the first active jet enthalpy enhancer 102.

[0053] Furthermore, in the first embodiment, the first economizer 101 and the first active jet enthalpy booster economizer 102 are connected through the refrigerant inlet pipe 103 of the external heat source heat exchanger, and the refrigerant temperature sensor 39 of the external heat source heat exchanger inlet is provided on the refrigerant inlet pipe 103 of the external heat source heat exchanger.

[0054] Furthermore, in the first embodiment, the first active jet enthalpy booster 102 enters the injector 5 through the injector high-pressure inlet pipe 104.

[0055] Furthermore, in the first embodiment, the fluid in the ejector branch passes through the first economizer 101 and then enters the ejector 5 through the low-pressure fluid inlet pipe 105.

[0056] Furthermore, in the second embodiment, an ejector outlet refrigerant pipe 106 is provided at the outlet end of the ejector 5, and the mixed fluid in the ejector 5 enters the second active jet enthalpy booster 107 through the ejector outlet refrigerant pipe 106.

[0057] For further information, please refer to [link / reference]. Figure 3 , Figure 3 A flowchart of a control method for a jet-induced enthalpy-enhanced high-efficiency heat pump system provided by the present invention; a control method for a jet-induced enthalpy-enhanced high-efficiency heat pump system, applicable to any of the above-mentioned examples, the control method comprising: S1: In response to the heating command, detect the operating parameters of the jet enthalpy-enhancing high-efficiency heat pump system and determine whether the heating start-up conditions are met; S2: If the heating start-up conditions are met, control the heat pump unit to heat, and adjust the compressor operating rate according to the preset return water temperature. S3: After the heat pump unit starts operating, determine whether the jet enthalpy-increasing high-efficiency heat pump system meets the jet enthalpy-increasing conditions; S4: If so, the jet enthalpy enhancement function is activated, and the opening of the main electronic expansion valve and the jet enthalpy enhancement electronic expansion valve are adjusted synchronously based on the intake superheat and injection superheat during the jet enthalpy enhancement process.

[0058] Specifically, upon receiving a heating command, the system responds by detecting the operating parameters of the vapor injection enthalpy-enhancing high-efficiency heat pump system and determining whether the heating operation conditions are met. Once the detected operating data meets the heating start-up conditions, the heat pump unit starts operating. First, a soft start is performed on the software. After the soft start has run for a period of time, normal operation control is implemented, adjusting the operating frequency of compressor 1 according to the set return water temperature target. After the heat pump unit has run for a period of time, it is determined whether the conditions for activating active vapor injection enthalpy enhancement are met. If so, the vapor injection enthalpy enhancement function is activated, and the opening degrees of the main electronic expansion valve 81 and the vapor injection enthalpy-enhancing electronic expansion valve 82 are synchronously adjusted according to the intake superheat and injection superheat during the vapor injection enthalpy enhancement process.

[0059] It should be noted that the heat pump unit is a heat pump subsystem, and the only difference between the two is in the name; the heat pump unit includes a compressor 1, a condenser 6, an evaporator 9, a water pump 21, and a subcooler, etc.

[0060] Furthermore, the operating parameters of the jet-induced enthalpy-enhanced high-efficiency heat pump system are detected and it is determined whether the heating start-up conditions are met, including: The set target value for the return water temperature is greater than the sum of the current return water temperature and the return water temperature hysteresis. The heat pump unit is functioning without fault; The heat pump unit's downtime is longer than the preset delay time; If the above conditions are met simultaneously, the water pump 21 will be started and the compressor 1 will begin soft start operation at a preset frequency.

[0061] Furthermore, after the heat pump unit has been running for a short period of time, it is determined whether the vapor injection enthalpy-enhancing high-efficiency heat pump system meets the vapor injection enthalpy-enhancing conditions, including: After the unit has been running for a while, we will continue to determine whether the conditions for opening the jet enthalpy enhancement are met. The conditions for activating jet enthalpy enhancement include: The heat pump unit is in heating mode and the soft start has ended; The outdoor ambient temperature detected by the outdoor ambient temperature sensor is lower than the set outdoor temperature threshold, and the water temperature detected by the external heat source inlet medium temperature sensor is greater than the sum of the temperature detected by the condenser outlet refrigerant temperature sensor and the preset condenser outlet refrigerant temperature sensor. If both of the above conditions are met simultaneously, then active jet enthalpy enhancement will be activated.

[0062] Furthermore, the jet enthalpy enhancement function is activated, and based on the intake superheat and injection superheat during the jet enthalpy enhancement process, the opening degrees of the main electronic expansion valve 81 and the jet enthalpy enhancement electronic expansion valve 82 are simultaneously adjusted, including: Open the jet enthalpy-enhancing electronic expansion valve 82 to its initial opening degree; The first temperature detected by the refrigerant temperature sensor 40 at the outlet of the external heat source heat exchanger and the second temperature detected by the outlet temperature sensor 38 of the vapor injection enthalpy-increasing electronic expansion valve are obtained. The actual injection superheat is calculated based on the first temperature and the second temperature. The actual injection superheat is defined as the difference between the first temperature and the second temperature. Adjust the opening of the jet enthalpy-enhancing electronic expansion valve 82 according to the actual jet superheat.

[0063] Among them, the superheat of the injection satisfies Formula 1; Formula 1: ΔT inj =T inj,out -T inj,in ; Where, ΔT inj For jet superheat; T inj,out The second temperature detected by the outlet temperature sensor 38 of the jet enthalpy-enhancing electronic expansion valve; T inj,in The first temperature detected by the refrigerant temperature sensor 40 at the outlet of the external heat source heat exchanger.

[0064] Specifically, the jet enthalpy-enhancing electronic expansion valve 82 is opened to its initial opening degree, and the external heat source hot water is used as the heat source for jet enthalpy enhancement. The water pump is turned on to keep the water flow constant. The first temperature detected by the refrigerant temperature sensor 40 at the outlet of the external heat source heat exchanger and the second temperature detected by the outlet temperature sensor 38 of the jet enthalpy-enhancing electronic expansion valve are collected in real time. The actual jet superheat is calculated based on the first and second temperatures. Then, based on the deviation between the actual jet superheat and the target jet superheat, the opening degree of the jet enthalpy-enhancing electronic expansion valve 82 is dynamically adjusted to stabilize the actual superheat near the target value.

[0065] Furthermore, the jet enthalpy enhancement function is activated, and based on the intake superheat and injection superheat during the jet enthalpy enhancement process, the opening degrees of the main electronic expansion valve 81 and the jet enthalpy enhancement electronic expansion valve 82 are simultaneously adjusted, respectively. This also includes: Adjusting the flow control valve 205 according to the temperature sensor specifically includes: The third temperature detected by the external heat source inlet medium temperature sensor 41 and the fourth temperature detected by the external heat source outlet medium temperature sensor 42 are obtained. When the third temperature is less than the sum of the first temperature and the first temperature hysteresis value, but greater than the first temperature, the flow regulating valve 205 is opened to inject the low-temperature refrigerant. or, When the fourth temperature is less than the second temperature and the hysteresis value of the second temperature, but greater than the second temperature, the flow regulating valve 205 opens to inject the low-temperature refrigerant.

[0066] Specifically, the control unit acquires the third temperature detected by the external heat source inlet medium temperature sensor 41 and the fourth temperature detected by the external heat source outlet medium temperature sensor 42 in real time. When the conditions are met: the third temperature is less than the sum of the first temperature and the first temperature hysteresis value, and is greater than the first temperature; or when the conditions are met: the fourth temperature is less than the second temperature and the second temperature hysteresis value, and is greater than the second temperature; the control unit outputs a command to open or increase the opening of the flow regulating valve 205 on the ejector branch to eject the low-temperature refrigerant and enhance heat exchange.

[0067] Furthermore, the jet enthalpy enhancement function is activated, and based on the intake superheat and injection superheat during the jet enthalpy enhancement process, the opening degrees of the main electronic expansion valve 81 and the jet enthalpy enhancement electronic expansion valve 82 are simultaneously adjusted, respectively. This also includes: The temperature detected by the intake temperature sensor 34 is acquired and recorded as the fifth temperature, and the temperature detected by the outdoor heat exchanger coil temperature sensor 33 is acquired and recorded as the sixth temperature. Adjust the opening of the main electronic expansion valve 81 according to the suction superheat of the evaporator 9; the suction superheat is defined as the difference between the fifth temperature and the sixth temperature.

[0068] Specifically, based on the adjustment of the jet enthalpy-increasing electronic expansion valve 82 and the flow regulating valve 205, the opening of the main electronic expansion valve 81 is adjusted independently according to the suction superheat of the evaporator 9, i.e., calculated through the outlet and inlet temperatures of the evaporator 9, to ensure that the evaporator 9 is always in a state of efficient heat exchange.

[0069] Furthermore, the regulatory methods also include: The jet enthalpy-enhanced high-efficiency heat pump system is tested. When the jet enthalpy-enhanced high-efficiency heat pump system meets the preset stop conditions, jet enthalpy enhancement stops and the jet enthalpy-enhanced electronic expansion valve 82 closes. The preset active jet enthalpy increase stop conditions include: The ambient temperature is higher than the preset ambient temperature. When the first temperature is less than the sum of the second temperature and the hysteresis value of the second temperature, or, When the fourth temperature is less than the sum of the third temperature and the hysteresis value of the third temperature.

[0070] Specifically, when any of the preset stop conditions are met, the jet enthalpy increase stops and the jet enthalpy increase electronic expansion valve 82 closes; the preset stop conditions include: the ambient temperature detected by the temperature sensor is greater than the set ambient temperature; the first temperature is less than the sum of the second temperature and the second temperature hysteresis value, or the fourth temperature is less than the sum of the third temperature and the third temperature hysteresis value.

[0071] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A jet-enhanced high-efficiency heat pump system with jet enthalpy enhancement, characterized in that, include: Heat pump subsystem and active jet enthalpy enhancement subsystem; The heat pump subsystem includes a compressor (1), a condenser (6), an evaporator (9), and a main electronic expansion valve (81). The active jet enthalpy enhancement subsystem includes: a jet enthalpy enhancement electronic expansion valve (82), an external heat source, and an injector (5); the compressor (1) is provided with an intermediate jet port; The outlet pipe of the condenser (6) is split into a first branch and a second branch; The refrigerant in the first branch enters the evaporator (9) after being throttled by the main electronic expansion valve (81); an ejector branch is branched off from the outlet of the evaporator (9) and is connected to the low-pressure ejector fluid inlet of the ejector (5) as an ejector flow. The refrigerant in the second branch is throttled by the jet enthalpy-increasing electronic expansion valve (82) and then enters the high-pressure drive fluid inlet of the ejector (5) as a drive flow; The outlet of the injector (5) is connected to the intermediate jet port, so that the mixed fluid formed by the jet stream and the drive stream mixing in the injector (5) is returned to the compressor (1).

2. The jet-induced enthalpy-enhancing high-efficiency heat pump system according to claim 1, characterized in that, At least one subcooler is provided in the passage between the throttling of the jet enthalpy-increasing electronic expansion valve (82) and the intermediate jet port, for the refrigerant flowing through it to exchange heat with the external heat source.

3. The jet-induced enthalpy-enhanced high-efficiency heat pump system according to claim 2, characterized in that, The subcooler includes a first active vapor injection enthalpy booster (102), which is disposed on the pipeline between the vapor injection enthalpy booster electronic expansion valve (82) and the receiving chamber of the injector (5).

4. The jet-induced enthalpy-enhancing high-efficiency heat pump system according to claim 3, characterized in that, Between the jet enthalpy-enhancing electronic expansion valve (82) and the first active jet enthalpy-enhancing economizer (102), a first economizer (101) is also provided; the ejector branch is connected to the injector (5) through the first economizer (101); The first economizer (101) and the first active jet enthalpy booster (102) are connected in series.

5. The jet-induced enthalpy-enhancing high-efficiency heat pump system according to claim 2, characterized in that, The subcooler includes a second active jet enthalpy enhancer (107), which is located on the pipeline between the outlet of the injector (5) and the intermediate jet port.

6. A method for regulating a jet-induced enthalpy-enhanced high-efficiency heat pump system, characterized in that, The control method, applicable to any one of claims 1 to 5, comprises: In response to a heating command, the operating parameters of the jet enthalpy-enhancing high-efficiency heat pump system are detected and it is determined whether the heating start-up conditions are met. If the heating start-up conditions are met, the heat pump unit is controlled to heat, and the operating rate of the compressor (1) is adjusted according to the preset return water temperature. After the heat pump unit has been running for a period of time, determine whether the jet enthalpy-enhancing high-efficiency heat pump system meets the jet enthalpy-enhancing conditions; If so, the jet enthalpy enhancement function is activated, and the opening of the main electronic expansion valve (81) and the jet enthalpy enhancement electronic expansion valve (82) are adjusted synchronously based on the intake superheat and injection superheat during the jet enthalpy enhancement process.

7. The control method according to claim 6, characterized in that, The activation of the jet enthalpy enhancement function, and the synchronous adjustment of the opening degrees of the main electronic expansion valve (81) and the jet enthalpy enhancement electronic expansion valve (82) based on the intake superheat and injection superheat during the jet enthalpy enhancement process, include: Open the jet enthalpy-increasing electronic expansion valve (82) to its initial opening degree; The first temperature detected by the refrigerant temperature sensor (40) at the outlet of the external heat source heat exchanger and the second temperature detected by the outlet temperature sensor (38) of the jet enthalpy-increasing electronic expansion valve are obtained. The actual injection superheat is calculated based on the first temperature and the second temperature, and the actual injection superheat is defined as the difference between the first temperature and the second temperature. Adjust the opening degree of the jet enthalpy-enhancing electronic expansion valve (82) according to the actual jet superheat.

8. The control method according to claim 7, characterized in that, The step of activating the jet enthalpy enhancement function and simultaneously adjusting the opening of the main electronic expansion valve (81) and the jet enthalpy enhancement electronic expansion valve (82) based on the intake superheat and injection superheat during the jet enthalpy enhancement process also includes: Adjusting the flow control valve (205) according to the temperature sensor specifically includes: The third temperature detected by the external heat source inlet medium temperature sensor (41) and the fourth temperature detected by the external heat source outlet medium temperature sensor (42) are obtained. When the third temperature is less than the sum of the first temperature and the first temperature hysteresis value, but greater than the first temperature, the flow regulating valve (205) is controlled to open to inject the low-temperature refrigerant. or, When the fourth temperature is less than the second temperature and the hysteresis value of the second temperature, but greater than the second temperature, the flow regulating valve (205) opens to inject the cryogenic refrigerant.

9. The control method according to claim 7 or 8, characterized in that, The step of activating the jet enthalpy enhancement function and simultaneously adjusting the opening of the main electronic expansion valve (81) and the jet enthalpy enhancement electronic expansion valve (82) based on the intake superheat and injection superheat during the jet enthalpy enhancement process also includes: The temperature detected by the intake temperature sensor (34) is recorded as the fifth temperature, and the temperature detected by the outdoor heat exchanger coil temperature sensor (33) is recorded as the sixth temperature. The opening of the main electronic expansion valve (81) is adjusted according to the intake superheat; the intake superheat is defined as the difference between the fifth temperature and the sixth temperature.

10. The control method according to claim 8, characterized in that, The control method also includes: The jet enthalpy-enhancing high-efficiency heat pump system is tested. When the jet enthalpy-enhancing high-efficiency heat pump system meets the preset stop conditions, the jet enthalpy enhancement stops and the jet enthalpy-enhancing electronic expansion valve (82) closes. The preset active jet enthalpy increase stop conditions include: The ambient temperature is higher than the preset ambient temperature. When the first temperature is less than the sum of the second temperature and the hysteresis value of the second temperature, or, When the fourth temperature is less than the sum of the third temperature and the third temperature hysteresis value.

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