Hot water supply system capable of automatically supplementing refrigerant

Abstract

The utility model relates to the technical field of high-temperature heat pumps, and discloses a hot water supply system capable of automatically supplementing refrigerants, which comprises an air source heat pump heat supply system, a waste heat heat supply system, a refrigerant supplementing system and a hot water supply loop. The air source heat pump heat supply system and the waste heat heat supply system are used for supplying heat to the hot water supply loop, and the refrigerant supplementing system is used for supplementing refrigerants to the hot water supply loop. The waste heat source and the air source are coupled, the potential influence of instability of a single heat source on system operation is effectively avoided, the adaptive capacity of the system to various heat source conditions is remarkably improved, and the working medium transmission mode of the compressor and the working medium transmission mode of the air pump are ingeniously fused. The system successfully solves the problem of normal work of the air source heat pump cascade high-temperature hot water system in different use environments, and ensures stable operation of the air source heat pump cascade high-temperature hot water system under various conditions.

Description

Technical Field

[0001] This utility model relates to the field of high-temperature heat pump technology, and more specifically, to a hot water supply system that can automatically replenish refrigerant. Background Technology

[0002] High-temperature heat pump technology originates from the expansion and upgrade of traditional heat pumps, aiming to meet the high-temperature heat energy needs of industry and commerce. It utilizes a small amount of electrical or mechanical energy to absorb heat from a low-temperature heat source and release it to a high-temperature environment through a thermodynamic cycle, achieving energy transfer and upgrading. With the growing awareness of environmental protection and sustainable development, high-temperature heat pumps use renewable energy as a heat source, achieving zero or low emissions and promoting energy recycling and energy conservation and emission reduction. In the industrial and commercial sectors, high-temperature heat pumps have broad application prospects, meeting the needs of high-temperature processes while contributing to energy conservation and environmental protection. Currently, fixed-frequency high-temperature heat pump water heaters rely on a single fixed-frequency compressor on the air source side. Under high-temperature environments, excessively high evaporation temperatures and pressures can easily exceed the compressor's operating limits, leading to malfunctions and reduced system reliability. Furthermore, heat pumps inevitably experience refrigerant loss or leakage during long-term operation, requiring on-site refueling by after-sales personnel, which is not only slow to respond and has a long refueling cycle but also incurs high labor costs. Utility Model Content

[0003] In order to overcome the shortcomings of the existing technology, this utility model provides a hot water supply system that can automatically replenish refrigerant and has the advantage of adaptability to heat source conditions.

[0004] To achieve the above objectives, the present invention provides the following technical solution.

[0005] In a first aspect, this application provides a hot water supply system capable of automatically replenishing refrigerant, which includes an air source heat pump heating system, a waste heat heating system, a refrigerant replenishment system, and a hot water supply circuit.

[0006] The air source heat pump heating system and the waste heat heating system are used to supply heat to the hot water supply circuit, and the refrigerant replenishment system is used to replenish refrigerant.

[0007] The air source heat pump heating system includes an air source side compressor, an evaporator-condenser, a first electronic throttling device, an air-cooled heat exchanger, and a three-way valve, all connected in a loop.

[0008] The waste heat heating system includes a plate heat exchanger, a three-way valve, an air source compressor, and an evaporator-condenser connected in a loop, wherein the plate heat exchanger is connected to the waste heat source inlet and the waste heat source outlet.

[0009] The refrigerant replenishment system includes an air-source side refrigerant pump, an evaporator-condenser, a first electronic throttling device, an air-cooled heat exchanger, and a three-way valve, all connected in a circulating manner, and the air-source side refrigerant pump is connected to the refrigerant tank.

[0010] The hot water supply circuit includes a circulating evaporator-condenser, a hot water side compressor, a water-cooled heat exchanger, and a second electronic throttling device, wherein the water-cooled heat exchanger is connected to the hot water return port and the hot water outlet.

[0011] In one embodiment of the first aspect, the hot water supply system capable of automatically replenishing refrigerant further includes a speed-regulating fan for supplying air to the air-cooled heat exchanger.

[0012] In one embodiment of the first aspect, the three-way valve includes three ports: A, C, and D. When D and A are connected, the air-cooled heat exchanger is connected to the air-source side compressor, and when D and C are connected, the air-cooled heat exchanger is connected to the air-source side refrigerant pump.

[0013] In one embodiment of the first aspect, the air source heat pump heating system further includes a second electrically operated shut-off valve and a third electrically operated shut-off valve, wherein the second electrically operated shut-off valve is disposed between the air-cooled heat exchanger and the air source side compressor, and the third electrically operated shut-off valve is disposed between the air-cooled heat exchanger and the evaporator-condenser.

[0014] In one embodiment of the first aspect, the air source heat pump heating system further includes an exhaust pressure sensor disposed between the air source side compressor and the evaporator-condenser.

[0015] In one embodiment of the first aspect, the air source heat pump heating system further includes an intake temperature sensor and an exhaust temperature sensor, wherein the intake temperature sensor is disposed between the air-cooled heat exchanger and the air source-side compressor, and the exhaust temperature sensor is disposed between the air source-side compressor and the evaporator-condenser.

[0016] In one embodiment of the first aspect, the waste heat supply system further includes a fourth electrically operated shut-off valve and a fifth electrically operated shut-off valve, wherein the fourth electrically operated shut-off valve is disposed between the plate heat exchanger and the three-way valve, and the fifth electrically operated shut-off valve is disposed between the plate heat exchanger and the first electronic throttling device.

[0017] In one embodiment of the first aspect, the waste heat heating system further includes a waste heat outlet water temperature sensor and a waste heat inlet water temperature sensor, wherein the waste heat inlet water temperature sensor is disposed between the plate heat exchanger and the waste heat source inlet, and the waste heat outlet water temperature sensor is disposed between the plate heat exchanger and the waste heat source outlet.

[0018] In one embodiment of the first aspect, the refrigerant replenishment system further includes a waste heat source water pump, which is disposed between the plate heat exchanger and the waste heat source inlet.

[0019] In one embodiment of the first aspect, the refrigerant replenishment system includes a first electrically operated shut-off valve and a filler, which are disposed between the refrigerant tank and the air-source-side refrigerant pump.

[0020] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0021] This invention couples a waste heat source with an air source, effectively mitigating the potential impact of a single unstable heat source on system operation and significantly improving the system's adaptability to various heat source conditions. By cleverly integrating the compressor and air pump as working fluid transmission modes, the system successfully solves the problem of normal operation of air source heat pump cascade high-temperature hot water systems under different usage environments, ensuring stable operation under various conditions. Furthermore, the system is equipped with an advanced automatic refrigerant replenishment function; once refrigerant deficiency is detected, the system can immediately activate the replenishment mechanism to ensure normal operation even under abnormal conditions. This design not only enhances the system's reliability but also achieves highly efficient and energy-saving operation of the air source heat pump cascade direct-output steam system, providing users with a more stable and efficient thermal energy solution. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall control process of this utility model.

[0023] In the diagram: 1. Air source side compressor; 2. Air source side refrigerant pump; 3. Exhaust pressure sensor; 4. Exhaust temperature sensor; 5. Evaporator / condenser; 6. First electronic throttling device; 7. Air-cooled heat exchanger; 8. Variable speed fan; 9. Suction pressure sensor; 10. Suction temperature sensor; 11. Three-way valve; 12. Hot water side compressor; 13. Water-cooled heat exchanger; 14. Hot water return port; 15. Hot water outlet; 16. Second electronic throttling device; 17. First electric shut-off valve; 18. Charging device; 19. Refrigerant tank; 20. Second electric shut-off valve; 21. Third electric shut-off valve; 22. Fourth electric shut-off valve; 23. Fifth electric shut-off valve; 24. Plate heat exchanger; 25. Waste heat outlet water temperature sensor; 26. Waste heat inlet water temperature sensor; 27. Waste heat source water pump; 28. Waste heat source inlet; 29. ​​Waste heat source outlet. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] like Figure 1 As shown, this utility model provides a hot water supply system capable of automatically replenishing refrigerant, an air source heat pump heating system, a waste heat heating system, a refrigerant replenishment system, and a hot water supply circuit. The air source heat pump heating system and the waste heat heating system are used to supply heat to the hot water supply circuit, and the refrigerant replenishment system is used to replenish refrigerant. In one specific embodiment, the hot water supply system capable of automatically replenishing refrigerant includes an air-source side compressor 1, an air-source side refrigerant pump 2, an exhaust pressure sensor 3, an exhaust temperature sensor 4, an evaporator-condenser 5, a first electronic throttling device 6, an air-cooled heat exchanger 7, a speed-regulating fan 8, an intake pressure sensor 9, an intake temperature sensor 10, a three-way valve 11, a hot water side compressor 12, a water-cooled heat exchanger 13, a hot water return port 14, a hot water outlet 15, a second electronic throttling device 16, a first electric shut-off valve 17, a charging device 18, a refrigerant tank 19, a second electric shut-off valve 20, a third electric shut-off valve 21, a fourth electric shut-off valve 22, a fifth electric shut-off valve 23, a plate heat exchanger 24, a waste heat outlet water temperature sensor 25, a waste heat inlet water temperature sensor 26, a waste heat source water pump 27, a waste heat source inlet water 28, and a waste heat source outlet water 29.

[0026] In one embodiment, the air source heat pump heating system includes an air source side compressor 1, an evaporator-condenser 5, a first electronic throttling device 6, an air-cooled heat exchanger 7, and a three-way valve 11, all connected in a loop. In another embodiment, the waste heat heating system includes a plate heat exchanger 24, a three-way valve 11, the air source side compressor 1, and the evaporator-condenser 5, all connected in a loop, wherein the plate heat exchanger 24 is connected to a waste heat source inlet 28 and a waste heat source outlet 29. In another embodiment, the refrigerant replenishment system includes an air source side refrigerant pump 2, an evaporator-condenser 5, a first electronic throttling device 6, an air-cooled heat exchanger 7, and a three-way valve 11, all connected in a loop, and the air source side refrigerant pump 2 is connected to a refrigerant tank 19. In yet another embodiment, the hot water supply circuit includes an evaporator-condenser 5, a hot water side compressor 12, a water-cooled heat exchanger 13, and a second electronic throttling device 16, all connected in a loop, and the water-cooled heat exchanger 13 is connected to a hot water return outlet 14 and a hot water outlet 15.

[0027] The hot water supply system described in this article, capable of automatically replenishing refrigerant, has multiple operating modes, including a waste heat source and air source coupling mode, an air source-side compressor operating mode, an air source-side refrigerant pump operating mode, a hot water-side compressor operating mode, a three-way valve switching mode, and an automatic refrigerant charging mode. Different operating modes can be switched by controlling the three-way valve and the shut-off valve.

[0028] Next, we will combine Figure 1 This invention describes the working method of a hot water supply system capable of automatically replenishing refrigerant.

[0029] The waste heat source coupled with the air source operates as follows. After system startup, preheated or circulated hot water is introduced through the waste heat source inlet 28, and the heat-exchanged water is discharged through the waste heat source outlet 29. Simultaneously, the waste heat outlet water temperature sensor 25 and the waste heat inlet water temperature sensor 26 of the plate heat exchanger are monitored in real time. When the waste heat outlet water temperature sensor 25 and the plate heat exchanger waste heat inlet water temperature sensor 26 meet the system operating conditions, the system automatically switches to waste heat source mode. At this time, the fourth electric shut-off valve 22 and the fifth electric shut-off valve 26... The shut-off valve 23 opens automatically, the waste heat source water pump 27 starts, and at the same time the second electric shut-off valve 20 and the third electric shut-off valve 21 on the air side close, the fan stops running, and the system uses the plate heat exchanger 24 to achieve efficient heat exchange. If the waste heat source water temperature fluctuates and no longer meets the operating conditions, the system will immediately and seamlessly switch to the air source mode, quickly close the fourth electric shut-off valve 22 and the fifth electric shut-off valve 23, stop the waste heat source water pump 27, open the second electric shut-off valve 20 and the third electric shut-off valve 21, start the fan, and exchange heat through the air-cooled heat exchanger 7.

[0030] This system can intelligently switch between waste heat source and air source modes. By monitoring the temperature in real time and automatically adjusting the electric shut-off valve and fan, it ensures efficient and stable heat exchange. When the waste heat source water temperature fluctuates, the system seamlessly switches to the air source to avoid operation interruption. This design improves the system's flexibility, reliability and energy efficiency, making it suitable for variable environments and achieving energy-saving and efficient operation.

[0031] The temperature of the waste heat source can reach a stable range, usually between 40-50℃, and its temperature variation is controlled within a small range, which can be considered to be within ±5℃, thus ensuring the stability and reliability of the waste heat source.

[0032] The working mode of the air source side compressor is as follows. The working fluid at room temperature in the system is first compressed by the air source side compressor 1, and then connected to the exhaust pressure sensor 3 and exhaust temperature sensor 4 through the exhaust port. After that, it enters the evaporator condenser 5 to exchange heat with the hot water side working fluid. After heat exchange, the working fluid flows through the first electronic throttling device 6 for throttling, and then enters the air-cooled heat exchanger 7. In the air-cooled heat exchanger 7, the working fluid and the speed-regulating fan 8 work simultaneously to achieve heat exchange with the air. After heat exchange, the working fluid passes through the suction pressure sensor 9 and suction temperature sensor 10 and enters the three-way valve 11. At this time, the D port and A port of the three-way valve 11 are connected to the suction port of the air source side compressor 1, thereby completing the cyclic working mode of the air source side compressor 1.

[0033] The system compresses a room-temperature working fluid via an air-source side compressor 1. The fluid then passes through an exhaust pressure sensor 3 and an exhaust temperature sensor 4 before entering an evaporator-condenser 5. After passing through a first electronic throttling device 6 and an air-cooled heat exchanger 7, it exchanges heat with the air, achieving efficient heat energy conversion. The working fluid ultimately returns to the air-source side compressor 1 via a three-way valve 11, forming a stable cycle. This design improves heat energy utilization efficiency and enhances system stability. Furthermore, intelligent sensor monitoring ensures efficient and safe system operation, making it suitable for various heat energy demand scenarios.

[0034] The operating mode of the air-source refrigerant pump is as follows. Driven by the air-source refrigerant pump 2, the working fluid at room temperature begins its circulation process. First, the working fluid passes through the exhaust port, sequentially through the exhaust pressure sensor 3 and exhaust temperature sensor 4 for pressure and temperature monitoring. Then, it enters the evaporator-condenser 5 to exchange heat with the hot water side working fluid. After heat exchange, the working fluid flows to the first electronic throttling device 6 for throttling and pressure reduction, adjusting its flow rate and pressure. Next, the working fluid enters the air-cooled heat exchanger 7, where the speed-regulating fan 8 operates synchronously. Through the air-cooled heat exchanger 7, the working fluid exchanges heat with the air, further regulating its temperature. After heat exchange, the working fluid flows through the suction pressure sensor 9 and suction temperature sensor 10 for further pressure and temperature monitoring. Finally, the working fluid enters the three-way valve 11, where the D port and C port of the three-way valve 11 are connected, guiding the working fluid back to the air inlet of the air-source refrigerant pump 2, thus completing the entire circulation operation mode of the air-source refrigerant pump.

[0035] The working fluid is circulated by an air-source-side refrigerant pump 2. Stable operation is ensured by sensors at the exhaust and intake ends. The working fluid efficiently exchanges heat in the evaporator-condenser 5 and the air-cooled heat exchanger 7. The flow and pressure are regulated by a first electronic throttling device 6, and finally, the fluid returns to the air-source-side refrigerant pump 2 via a three-way valve 11, forming a closed loop. This design improves thermal energy conversion efficiency, ensures efficient and stable system operation, and is suitable for various thermal energy management needs.

[0036] The hot water side compressor operates as follows: the high-temperature working fluid in the system is discharged from the hot water side compressor 12 and enters the water-cooled heat exchanger 13 through the exhaust port. At the same time, low-temperature water enters the water-cooled heat exchanger 13 from the hot water return port 14 and exchanges heat with the high-temperature working fluid. After being heated, it is discharged from the hot water outlet 15. The high-temperature working fluid that has completed the heat exchange is condensed in the water-cooled heat exchanger 13 and then flows through the second electronic throttling device 16 for throttling and pressure reduction. The throttled working fluid enters the evaporator condenser 5 and further exchanges heat with the working fluid on the air source side. Finally, it returns to the suction port of the hot water side compressor 12, thus completing the entire cycle process on the hot water side.

[0037] The high-temperature working fluid is driven by the hot water side compressor 12 to circulate and efficiently exchange heat with the low-temperature water in the water-cooled heat exchanger 13, thus transferring heat energy. After being throttled and depressurized, the working fluid enters the evaporator-condenser 5 for further heat exchange and finally returns to the compressor, forming a closed loop. This design improves the efficiency of heat energy utilization, ensures stable and efficient system operation, and is suitable for various heat energy conversion and utilization scenarios.

[0038] The three-way valve switching operation mode is described below. The three-way valve's switching principle primarily relies on temperature changes at the system's operating environment. When the ambient temperature rises, causing a corresponding increase in suction pressure, the suction pressure sensor 9 detects this change. Once the suction pressure exceeds the set value of 1.5 MPa, the three-way valve 11 automatically switches its operating state, connecting port D and port A. At this time, the air source side compressor 1 starts running, while the air source side refrigerant pump 2 is shut down. Conversely, when the ambient temperature decreases and the suction pressure drops below 1.5 MPa, the three-way valve 11 switches to a state where ports D and C are connected. At this time, the air source side refrigerant pump 2 starts running, while the air source side compressor 1 stops. This automatic adjustment mechanism ensures that the system can operate efficiently according to changes in ambient temperature.

[0039] By monitoring changes in ambient temperature through the intake pressure sensor 9, the working state of the three-way valve 11 is intelligently adjusted to achieve automatic switching between the air source compressor 1 and the air source refrigerant pump 2. When the temperature is high, the air source compressor 1 starts cooling; when the temperature is low, the air source refrigerant pump 2 runs heating. This automatic adjustment mechanism ensures efficient system operation, adapts to different ambient temperatures, and improves overall energy efficiency and stability.

[0040] The automatic refrigerant charging mode is as follows. During system operation, key parameters such as suction temperature, suction pressure, exhaust temperature, and exhaust pressure are monitored in real time. When refrigerant loss or leakage causes a drop in suction temperature, a decrease in suction pressure, an increase in exhaust temperature, and an increase in exhaust pressure, the system automatically detects these parameter changes. Once all monitored data reach preset thresholds, indicating insufficient refrigerant, the first electric shut-off valve 17 automatically opens and simultaneously starts the charging device 18, injecting refrigerant from the refrigerant tank 19 into the system to replenish the missing refrigerant. When the system detects that parameters such as suction temperature, suction pressure, exhaust temperature, and exhaust pressure have returned to normal ranges, the first electric shut-off valve 17 automatically closes, and the charging device 18 stops working, thereby ensuring that the refrigerant charge in the system remains at a reasonable level, allowing the system to operate stably even in the event of refrigerant loss or leakage.

[0041] The system monitors key parameters in real time, intelligently detects refrigerant loss, and automatically charges refrigerant to maintain a reasonable level. When the suction temperature and pressure, as well as the exhaust temperature and pressure, are abnormal, the system initiates the charging process to ensure stable operation. This design improves the system's reliability and automation, effectively addresses refrigerant leaks, and ensures the system continues to work efficiently.

[0042] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0043] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A hot water supply system capable of automatically replenishing refrigerant, characterized by: The hot water supply system capable of automatically supplementing refrigerant comprises an air source heat pump heating system, a waste heat heating system, a refrigerant supplementing system and a hot water supply circuit; The air source heat pump heating system and the waste heat heating system are used for heating the hot water supply circuit, and the refrigerant supplementing system is used for supplementing refrigerant. The air source heat pump heating system comprises an air source side compressor (1), an evaporative condenser (5), a first electronic throttling device (6), an air-cooled heat exchanger (7) and a three-way valve (11) connected in a circulation manner. The waste heat heating system comprises a plate heat exchanger (24), the three-way valve (11), the air source side compressor (1) and the evaporative condenser (5) connected in a circulation manner, wherein the plate heat exchanger (24) is connected with a waste heat source water inlet (28) and a waste heat source water outlet (29). The refrigerant supplementing system comprises the air source side fluorine pump (2), the evaporative condenser (5), the first electronic throttling device (6), the air-cooled heat exchanger (7) and the three-way valve (11) connected in a circulation manner, and the air source side fluorine pump (2) is connected with a refrigerant tank (19). The hot water supply circuit comprises the evaporative condenser (5), a hot water side compressor (12), a water-cooled heat exchanger (13) and a second electronic throttling device (16) connected in a circulation manner, and the water-cooled heat exchanger (13) is connected with a hot water return water inlet (14) and a hot water outlet (15).

2. The hot water supply system capable of automatically supplementing refrigerant according to claim 1, characterized by, The hot water supply system capable of automatically supplementing refrigerant further comprises a speed-regulating fan (8) used for delivering air to the air-cooled heat exchanger (7).

3. The hot water supply system capable of automatically supplementing refrigerant according to claim 1, wherein The three-way valve (11) comprises three ports of A, C and D, when D and A are communicated, the air-cooled heat exchanger (7) and the air source side compressor (1) are communicated, and when D and C are communicated, the air-cooled heat exchanger (7) and the air source side fluorine pump (2) are communicated.

4. The hot water supply system capable of automatically supplementing refrigerant according to any one of claims 1 to 3, characterized in that, The air source heat pump heating system further comprises a second electrically-operated stop valve (20) and a third electrically-operated stop valve (21), wherein the second electrically-operated stop valve (20) is arranged between the air-cooled heat exchanger (7) and the air source side compressor (1), and the third electrically-operated stop valve (21) is arranged between the air-cooled heat exchanger (7) and the evaporative condenser (5).

5. The hot water supply system capable of automatically supplementing refrigerant according to any one of claims 1 to 3, characterized in that, The air source heat pump heating system further comprises an exhaust pressure sensor (3) arranged between the air source side compressor (1) and the evaporative condenser (5).

6. The self-refrigerantable hot water supply system according to any one of claims 1 to 3, wherein The air source heat pump heating system further comprises a suction temperature sensor (10) and an exhaust temperature sensor (4), wherein the suction temperature sensor (10) is arranged between the air-cooled heat exchanger (7) and the air source side compressor (1), and the exhaust temperature sensor (4) is arranged between the air source side compressor (1) and the evaporative condenser (5).

7. The self-refrigerantable hot water supply system according to any one of claims 1 to 3, wherein The waste heat supply system further comprises a fourth electric stop valve (22) and a fifth electric stop valve (23), wherein the fourth electric stop valve (22) is arranged between the plate heat exchanger (24) and the three-way valve (11), and the fifth electric stop valve (23) is arranged between the plate heat exchanger (24) and the first electronic throttling device (6).

8. The self-refrigerantable hot water supply system according to any one of claims 1 to 3, wherein The waste heat supply system further comprises a waste heat outlet water temperature sensor (25) and a waste heat inlet water temperature sensor (26), wherein the waste heat inlet water temperature sensor (26) is arranged between the plate heat exchanger (24) and the waste heat source inlet (28), and the waste heat outlet water temperature sensor (25) is arranged between the plate heat exchanger (24) and the waste heat source outlet (29).

9. The self-refrigerantable hot water supply system according to any one of claims 1 to 3, wherein The refrigerant supplement system further comprises a waste heat source water pump (27), which is arranged between the plate heat exchanger (24) and the waste heat source inlet (28).

10. The self-refrigerantable hot water supply system according to any one of claims 1 to 3, wherein The refrigerant supplement system comprises a first electric stop valve (17) and a charger (18), which are arranged between the refrigerant tank (19) and the air source side fluorine pump (2).

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