Novel multi-mode cascade high-temperature heat pump unit

Abstract

The utility model relates to the technical field of heat pump devices, in particular to a novel multi-mode cascade high-temperature heat pump unit which comprises a water circulation system, a low-temperature-stage circulation system and a high-temperature-stage circulation system. A high-temperature-stage condenser of the high-temperature-stage circulation system exchanges heat with a user-side heating medium to supply heat to a user, the water circulation system comprises a water supply pipeline, a user load module, a circulation pump and a proportional-integral three-way adjusting valve, and the user load module, the circulation pump and the proportional-integral three-way adjusting valve are sequentially arranged on the water supply pipeline. The proportional-integral three-way regulating valve is positioned at one end of the condensing evaporator; the first flow guide channel, the second flow guide channel and the third flow guide channel are matched for heat exchange, the two compressors can work at the same time in the extremely low temperature environment to achieve two-stage operation heating, single-stage operation heating can be achieved after the environment is heated, and it is guaranteed that the system can operate in a dual-mode mode.

Description

Technical Field

[0001] This utility model relates to the field of heat pump device technology, specifically to a novel multi-mode cascade high-temperature heat pump unit. Background Technology

[0002] In the field of heat pump technology, cascade heat pump systems are widely used because they can achieve high-temperature heating. Traditional cascade heat pump systems typically employ a fixed two-stage compression cycle mode, achieving heat output through the series operation of low-temperature and high-temperature cycle systems.

[0003] However, these systems exhibit the following significant drawbacks in practical applications: traditional cascade heat pump systems have limited adaptability when facing wide temperature ranges. When the outdoor ambient temperature is high, the system still needs to maintain a two-stage compression mode, causing the compressor to operate at a high compression ratio. This not only increases power consumption but may also lead to decreased system efficiency and accelerated component wear due to compression ratio imbalance. Conversely, in extremely low temperature environments, a single-stage operation mode is insufficient to meet heating demands, resulting in inadequate heating capacity and an inability to stably provide a high-temperature heat source. Utility Model Content

[0004] This utility model addresses the shortcomings of existing technologies by providing a novel multi-mode cascade high-temperature heat pump unit that can provide normal heating in ultra-low temperature environments, supplying hot water that meets temperature requirements, and can also provide normal heating in low-temperature environments, enabling switching between single-stage and dual-stage compression modes.

[0005] To achieve the above technical objectives, this utility model proposes the following technical solution: a novel multi-mode cascade high-temperature heat pump unit, comprising a water circulation system, a low-temperature stage circulation system, and a high-temperature stage circulation system. The low-temperature stage circulation system and the high-temperature stage circulation system are connected through a condenser-evaporator. The high-temperature stage condenser of the high-temperature stage circulation system exchanges heat with the user-side heat medium to provide heat to the user. The water circulation system includes a water supply pipeline and a user load module, a circulation pump, and a proportional-integral three-way regulating valve sequentially arranged on the water supply pipeline. The condenser-evaporator is installed on the water supply pipeline. The proportional-integral three-way regulating valve is located at one end of the condenser-evaporator. One outlet of the proportional-integral three-way regulating valve is connected to an inlet branch, and the other end of the inlet branch is connected to the water supply pipeline located at the other end of the condenser-evaporator.

[0006] Furthermore, the cryogenic circulation system includes a cryogenic compressor, a four-way valve, a cryogenic evaporator, a cryogenic expansion valve, a cryogenic dryer filter, a cryogenic liquid storage tank, and a condenser-evaporator. The cryogenic evaporator, cryogenic expansion valve, cryogenic filter, cryogenic liquid storage tank, condenser-evaporator, and cryogenic compressor are connected through a first circulation pipeline. The exhaust port of the cryogenic compressor is connected to the four-way valve. The other three sides of the four-way valve are respectively connected to the condenser-evaporator, the cryogenic evaporator, and the expansion container. The other side of the expansion container is connected to the cryogenic compressor.

[0007] Furthermore, the high-temperature circulating system includes a high-temperature compressor, a high-temperature condenser, a high-temperature liquid receiver, a high-temperature dryer filter, and a high-temperature expansion valve. The high-temperature compressor, high-temperature condenser, high-temperature liquid receiver, high-temperature dryer filter, high-temperature expansion valve, and condenser-evaporator are connected through a second circulating pipeline. The high-temperature condenser is placed inside a heating tank.

[0008] Furthermore, the condenser-evaporator includes an outer shell and a first heat exchange plate and a second heat exchange plate distributed within the outer shell, and a first guide channel, a second guide channel and a third guide channel between the first heat exchange plate, the second heat exchange plate and the inner wall of the outer shell.

[0009] Furthermore, both the first heat exchange plate and the second heat exchange plate have an S-shaped structure.

[0010] Furthermore, a first guide plate is provided on the inner wall of the outer shell near the first heat exchange plate, and a second guide plate is provided on the inner wall of the outer shell near the second heat exchange plate.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: Through the coordinated heat exchange of the first guide channel, the second guide channel and the third guide channel, this utility model can achieve dual-stage heating by having two compressors work simultaneously in extremely low temperature environments, and can also achieve single-stage heating after the environment warms up, ensuring that the system can operate in both modes; at the same time, this utility model enables the low-temperature compressor to operate independently, which can provide a stable heat source and avoid the problem that traditional cascade heat pumps cannot operate a single compressor, effectively reducing power consumption. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0013] Figure 2 This is a schematic diagram of the internal structure of the condenser-evaporator of this utility model.

[0014] In the diagram, 1. Water circulation system; 11. Water supply pipeline; 12. User load module; 13. Circulation pump; 14. Proportional-integral three-way regulating valve; 2. Low-temperature stage circulation system; 21. Low-temperature stage compressor; 22. Four-way valve; 23. Low-temperature stage evaporator; 24. Low-temperature stage expansion valve; 25. Low-temperature stage dryer filter; 26. Low-temperature stage liquid storage tank; 27. Expansion container; 3. High-temperature stage circulation system; 31. High-temperature stage compressor; 32. High-temperature stage condenser; 33. High-temperature stage liquid storage tank; 34. High-temperature stage dryer filter; 35. High-temperature stage expansion valve; 4. Condenser-evaporator; 41. Outer shell; 42. First heat exchange plate; 43. Second heat exchange plate; 44. First guide channel; 45. Second guide channel; 46. Third guide channel; 47. First guide plate; 48. Second guide plate; 5. Inlet branch; 6. First circulation pipeline; 7. Second circulation pipeline. Detailed Implementation

[0015] The following are specific embodiments of the present invention, and the technical solution of the present invention will be further described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0016] This utility model provides a novel multi-mode cascade high-temperature heat pump unit, including a water circulation system 1, a low-temperature stage circulation system 2, and a high-temperature stage circulation system 3. The low-temperature stage circulation system 2 and the high-temperature stage circulation system 3 are connected by a condenser-evaporator 4. The condenser of the high-temperature stage circulation system 3 exchanges heat with the user-side heat medium to provide heat to the user. The water circulation system 1 includes a water supply pipeline 11 and a user load module 12, a circulation pump 13, and a proportional-integral three-way regulating valve 14 sequentially arranged on the water supply pipeline 11. The condenser-evaporator 4 is installed on the water supply pipeline 11. The proportional-integral three-way regulating valve 14 is located at one end of the condenser-evaporator 4. A water inlet branch 5 is connected to one outlet of the proportional-integral three-way regulating valve 14. The other end of the water inlet branch 5 is connected to the water supply pipeline 11 located at the other end of the condenser-evaporator 4. The low-temperature stage circulation system 2 includes a low-temperature stage compressor 21, a four-way valve 22, a low-temperature stage evaporator 23, a low-temperature stage expansion valve 24, a low-temperature stage dryer filter 25, a low-temperature stage liquid storage tank 26, and an expansion container 27. The low-temperature stage evaporator 23, low-temperature stage expansion valve 24, low-temperature stage dryer filter 25, low-temperature stage liquid storage tank 26, and low-temperature stage compressor 21 are connected via a first circulation pipeline 6. The exhaust port of the low-temperature stage compressor 21 is connected to the four-way valve 22. The other three sides of the four-way valve 22 are respectively connected to the condenser evaporator 4, the low-temperature stage evaporator 23, and the expansion container 27. The other side of the expansion container 27 is connected to the low-temperature stage compressor 21. The high-temperature stage circulation system 3 includes a high-temperature stage compressor 31 and a high-temperature stage condenser 3. 2. The high-temperature stage liquid receiver 33, high-temperature stage dryer filter 34, and high-temperature stage expansion valve 35 are connected by a second circulation pipeline 7. The high-temperature stage compressor 31, high-temperature stage condenser 32, high-temperature stage liquid receiver 33, high-temperature stage dryer filter 34, high-temperature stage expansion valve 35, and condenser-evaporator 4 are connected by a second circulation pipeline 7. The high-temperature stage condenser 32 is placed in the heating tank 9 to heat the water in the heating tank 9. In this embodiment, the low-temperature stage circulation system 2 and the high-temperature stage circulation system 3 are both existing technologies and will not be described in detail in this embodiment. The user load module 12, circulation pump 13, proportional integral three-way regulating valve 14 of the water circulation system 1 are sequentially connected to the condenser-evaporator 4 and the high-temperature stage condenser 32 through the water supply pipeline 11 to form a closed-loop water system.

[0017] Dual-stage heating mode

[0018] like Figure 1As shown, under heating operation, this system is suitable for ultra-low temperature environments (such as below -30℃) or high water temperature requirements (such as >80℃). The system operates in a cascade heating mode. The proportional-integral three-way regulating valve 14 is controlled to prevent water in the water supply line 11 from flowing through the condenser-evaporator 4. The four-way valve 22 is opened, and the high-temperature, high-pressure gaseous refrigerant from the low-temperature stage compressor 21 enters the A channel of the condenser-evaporator 4 through the four-way valve 22. There, it undergoes cascade heat exchange with the refrigerant in the high-temperature stage circulation system 3 in the B channel of the condenser-evaporator 4, condensing into high-pressure liquid refrigerant. This high-pressure liquid refrigerant flows out of the condenser-evaporator 4 and sequentially passes through the low-temperature stage storage tank 26, the low-temperature stage dryer filter 25, and the low-temperature stage expansion valve 24. Under the action of the low-temperature stage expansion valve 24, the high-pressure liquid refrigerant is throttled into a low-temperature, low-pressure gas-liquid two-phase refrigerant, which then enters the low-temperature evaporator... The generator 23 absorbs heat from the ambient air and vaporizes into a low-temperature, low-pressure gaseous refrigerant, which then returns to the low-temperature stage compressor 21 through the four-way valve 22, completing the first stage heat pump heating cycle. The high-temperature, high-pressure gaseous refrigerant in the high-temperature stage compressor 31 exchanges heat with the circulating water through the high-temperature stage condenser 32. The refrigerant in the high-temperature stage condenser 32 is converted into a high-pressure liquid refrigerant, which then passes through the high-temperature stage water tank 33, the high-temperature stage dryer filter 34, and the high-temperature stage expansion valve 35 in sequence. Under the action of the high-temperature stage expansion valve 35, the high-temperature liquid refrigerant is throttled into a low-temperature, low-pressure gas-liquid two-phase refrigerant, which then enters the B channel of the condenser-evaporator 4 and exchanges heat with the high-temperature, high-pressure gaseous refrigerant in the A channel. The low-temperature, low-pressure gas-liquid two-phase refrigerant entering the other side of the condenser-evaporator 4 is converted into a low-temperature, low-pressure gaseous refrigerant, realizing a double-layer heat pump cycle.

[0019] Single-stage heating mode I

[0020] Only the low-temperature stage cycle 2 operates independently, suitable for scenarios with high ambient temperatures (e.g., ambient temperature > -7℃) or low required water temperatures (e.g., < 60℃). The proportional-integral three-way regulating valve 14 is controlled to keep channel C in a flowing state, closing the inlet branch 5 and the high-temperature stage cycle system 3. The high-temperature, high-pressure gaseous refrigerant from the low-temperature stage compressor 21 enters channel A of the condenser-evaporator 4 through the four-way valve 22. The water in channel C undergoes heat exchange, and after heat exchange, the water in channel C is transported along the water supply pipeline 11 to the user load module 10, achieving single-stage heating.

[0021] Single-stage heating mode II

[0022] Only the high-temperature stage circulation 3 operates independently, suitable for scenarios with low water temperature requirements (such as requiring warm water of 20-30℃). In this embodiment, hot water is used as the heat source. The proportional integral three-way regulating valve 14 is adjusted to control the flow rate of the second guide channel 45 and the inlet branch 5. The condenser evaporator 4 absorbs the temperature of the return water from the water supply pipeline 11 and converts the refrigerant in the B channel of the condenser evaporator 4 into a low-temperature, low-pressure gaseous refrigerant. The low-temperature, low-pressure gaseous refrigerant enters the high-temperature stage condenser 32 through the high-temperature stage compressor 31 and exchanges heat with the circulating water in the high-temperature stage condenser 32, so that the circulating water is heated. Part of the heated water flows through the C channel of the condenser evaporator 4 and merges into the water supply pipeline 11, and the other part passes through the water supply branch 6 and merges into the water supply pipeline 11. Under the action of the circulation pump 13, it is delivered to the user load module 12 for use.

[0023] The condenser-evaporator 4 includes an outer shell 41 and a first heat exchange plate 42 and a second heat exchange plate 43 distributed within the outer shell 41. A first guide channel 44, a second guide channel 45, and a third guide channel 46 are formed between the first heat exchange plate 42, the second heat exchange plate 43, and the inner wall of the outer shell 41. The first guide channel 44 has a high-pressure circulation inlet and a high-pressure circulation outlet at both ends, the second guide channel 45 has a circulation inlet and a circulation outlet at both ends, and the third guide channel 46 has a low-pressure circulation inlet and a low-pressure circulation outlet at both ends.

[0024] like Figure 2 As shown, it should be noted that the A, B, and C channels of the condenser-evaporator 4 are equivalent to the first guide channel 44, the third guide channel 46, and the second guide channel 45 in this embodiment. The first guide channel 44 is used to flow through the refrigerant of the low-temperature stage circulation system 2, and the third guide channel 46 is used to flow through the refrigerant of the high-temperature stage circulation system 3. The high-pressure circulation inlet is connected to the four-way valve 202, the high-pressure circulation outlet is connected to the low-temperature stage liquid storage tank 26, and the circulation inlet and circulation outlet are respectively connected to the water supply pipeline 11. The low-pressure circulation inlet is connected to the high-temperature stage expansion valve 35, and the low-pressure circulation outlet is connected to the high-temperature stage compressor 31.

[0025] Both the first heat exchange plate 42 and the second heat exchange plate 43 have an S-shaped structure.

[0026] like Figure 2 As shown, the S-shaped structure increases the contact area and residence time, thereby improving the heat exchange effect.

[0027] A first guide plate 47 is provided on the inner wall of the outer casing 41 near the first heat exchange plate 42, and a second guide plate 48 is provided on the inner wall of the outer casing 41 near the second heat exchange plate 43.

[0028] like Figure 2As shown, the first guide plate 47 and the second guide plate 48 can control the refrigerant to further improve the flow direction of the refrigerant in the guide channel, and can also increase the residence time and improve the heat exchange effect.

[0029] Principle: In the dual-stage heating mode, the proportional-integral three-way regulating valve 14 is controlled to keep the second guide channel 45 in a non-flowing state. Water in the water supply pipe 11 flows along the inlet branch 5 to the water supply pipe 11 at one end of the proportional-integral three-way regulating valve 14. The four-way valve 22 opens, and the refrigerant of the low-temperature stage compressor 21 enters the first guide channel 44 through the four-way valve 22. The low-temperature, low-pressure gas-liquid two-phase refrigerant formed by the high-temperature stage expansion valve 35 enters the third guide channel 46. The water in the second guide channel 45 is in a static state. Water acts as a heat conductor. The high-temperature and high-pressure gaseous refrigerant in the first guide channel 44 exchanges heat with the low-temperature and low-pressure gas-liquid two-phase refrigerant in the third guide channel 46, so that the low-temperature and low-pressure gas-liquid two-phase refrigerant in the third guide channel 46 is converted into a low-temperature and low-pressure gaseous refrigerant. The high-temperature stage compressor 31 compresses the low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gaseous refrigerant, which then exchanges heat with the circulating water through the high-temperature stage condenser 32. The circulating water is heated and transported to the user load module 10 by the circulating pump 13 to realize the dual-stage stacked heat pump circulation heating.

[0030] Single-stage heating mode: Control the proportional-integral three-way regulating valve 14 to keep the second guide channel 45 in a flowing state, close the water inlet branch 5 and the high-temperature stage circulation system 3, and the high-temperature and high-pressure gaseous refrigerant of the low-temperature stage compressor 21 enters the first guide channel 44 through the four-way valve 22 to exchange heat with the water in the second guide channel 45. After the heat exchange, the water in the second guide channel 45 is transported to the user load module 10 by the circulation pump 13 along the water supply pipeline 11 to achieve single-stage heating.

[0031] Single-stage heating mode II: Only the high-temperature stage circulation 3 operates independently. The proportional-integral three-way regulating valve 14 is adjusted to control the flow rate of the second guide channel 45 and the water inlet branch 5. The refrigerant in the third guide channel 46 absorbs the heat of the water in the second guide channel 45 and is converted into a low-temperature, low-pressure gaseous refrigerant. The low-temperature, low-pressure gaseous refrigerant enters the high-temperature stage condenser 32 through the high-temperature stage compressor 31 and exchanges heat with the circulating water in the high-temperature stage condenser 32, so that the circulating water is heated. Part of the heated water flows through the second guide channel 45 and merges into the water supply pipeline 11, and the other part passes through the water supply branch 5 and merges into the water supply pipeline 11. Under the action of the circulation pump 13, it is delivered to the user load module 12 for use.

[0032] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to replace them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A novel multi-mode cascade high-temperature heat pump unit, characterized in that: The system includes a water circulation system (1), a low-temperature circulation system (2), and a high-temperature circulation system (3). The low-temperature circulation system (2) and the high-temperature circulation system (3) are connected by a condenser-evaporator (4). The high-temperature condenser of the high-temperature circulation system (3) exchanges heat with the heat medium on the user side to provide heat to the user. The water circulation system (1) includes a water supply pipeline (11) and a user load module (12), a circulation pump (13), and a proportional-integral three-way regulating valve (14) arranged sequentially on the water supply pipeline (11). The condenser-evaporator (4) is installed on the water supply pipeline (11). The proportional-integral three-way regulating valve (14) is located at one end of the condenser-evaporator (4). A water inlet branch (5) is connected to one outlet of the proportional-integral three-way regulating valve (14). The other end of the water inlet branch (5) is connected to the water supply pipeline (11) located at the other end of the condenser-evaporator (4).

2. The novel multi-mode cascade high-temperature heat pump unit according to claim 1, characterized in that: The low-temperature circulating system (2) includes a low-temperature compressor (21), a four-way valve (22), a low-temperature evaporator (23), a low-temperature expansion valve (24), a low-temperature dryer filter (25), a low-temperature liquid storage tank (26), and an expansion container (27). The low-temperature evaporator (23), the low-temperature expansion valve (24), the low-temperature dryer filter (25), the low-temperature liquid storage tank (26), and the low-temperature compressor (21) are connected through a first circulating pipeline (6). The exhaust port of the low-temperature compressor (21) is connected to the four-way valve (22). The other three sides of the four-way valve (22) are connected to the condenser evaporator (4), the low-temperature evaporator (23), and the expansion container (27), respectively. The other side of the expansion container (27) is connected to the low-temperature compressor (21).

3. The novel multi-mode cascade high-temperature heat pump unit according to claim 1, characterized in that: The high-temperature circulating system (3) includes a high-temperature compressor (31), a high-temperature condenser (32), a high-temperature liquid receiver (33), a high-temperature dryer filter (34), and a high-temperature expansion valve (35). The high-temperature compressor (31), the high-temperature condenser (32), the high-temperature liquid receiver (33), the high-temperature dryer filter (34), the high-temperature expansion valve (35), and the condenser evaporator (4) are connected by a second circulating pipeline (7). The high-temperature condenser (32) is installed on the water supply pipeline (11).

4. A novel multi-mode cascade high-temperature heat pump unit according to claim 1, characterized in that: The condenser-evaporator (4) includes an outer shell (41) and a first heat exchange plate (42) and a second heat exchange plate (43) distributed inside the outer shell (41). A first guide channel (44), a second guide channel (45) and a third guide channel (46) are formed between the first heat exchange plate (42), the second heat exchange plate (43) and the inner wall of the outer shell (41).

5. A novel multi-mode cascade high-temperature heat pump unit according to claim 4, characterized in that: Both the first heat exchange plate (42) and the second heat exchange plate (43) are S-shaped structures.

6. A novel multi-mode cascade high-temperature heat pump unit according to claim 5, characterized in that: A first guide plate (47) is provided on the inner wall of the outer shell (41) near the first heat exchange plate (42), and a second guide plate (48) is provided on the inner wall of the outer shell (41) near the second heat exchange plate (43).

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