High-temperature heat pump system with gas increasing and enthalpy spraying functions

Abstract

The utility model provides a high-temperature heat pump system with gas increasing and enthalpy spraying functions, which comprises a first-stage heat pump system, a second-stage heat pump system and a water supply system connected with the first-stage heat pump system and the second-stage heat pump system. The first-stage heat pump system comprises an enthalpy spraying compressor, a four-way valve, a first-stage heat exchanger, a first-stage throttler, an evaporator and a separator which are connected through a refrigerant pipeline to form a first-stage refrigerant circulation loop, the second-stage heat pump system comprises a second-stage economizer, and the evaporator is connected with an air-increasing enthalpy spraying throttler; and a refrigerant outlet of the evaporator, the gas-increasing and enthalpy-spraying throttler, the secondary economizer and an enthalpy-spraying opening of the enthalpy-spraying compressor form an air suction loop. The enthalpy spraying compressor is simple in structure, only one compression process of an existing enthalpy spraying compressor is upgraded to two compression processes, the refrigerant circulation amount is increased, the supercooling degree of a refrigerant entering the enthalpy spraying compressor is improved through the second-stage economizer, and therefore the system capacity is improved, and the enthalpy spraying compressor can still operate normally in the ultralow-temperature environment.

Description

Technical Field

[0001] The utility model relates to the technical field of heat pumps, in particular to a high-temperature heat pump system with a gas injection enthalpy increasing function. Background Art

[0002] The air source heat pump system includes a heat pump unit, which is mainly composed of a compressor, a condensing heat exchanger, a throttling device, and an evaporating heat exchanger connected in sequence through a working fluid pipeline to form a circulation loop.

[0003] At present, many air source heat pumps operate at low temperatures. Due to the large temperature difference, the temperature of the hot water generated is not too high, especially in the north where the outdoor temperature is -30°C. The existing heat pumps can only reach around 50°C, absorbing heat from the environment and then raising the water temperature to 50°C. The temperature difference in the middle is 80°C, and the existing heat pumps cannot meet the requirements.

[0004] To this end, the methods commonly used to improve the low-temperature heating capacity of existing heat pump systems mainly include the following: increasing the heating capacity and air outlet temperature by adding electric auxiliary heating to the indoor unit, increasing the heating capacity by increasing the heat exchanger, increasing the compressor displacement to increase the heating capacity, increasing the compressor operating frequency to increase the heating capacity, and increasing the heating capacity by increasing the enthalpy of the jet.

[0005] However, the above structure still has the problems of complex structure, low energy utilization and high manufacturing cost. In particular, the one-stage jet enthalpy increase method used in the market, although it can improve the heating capacity, may still be insufficient in ultra-low temperature environment, affecting the user experience. Utility Model Content

[0006] The utility model aims to solve the shortcomings in the prior art and proposes a high-temperature heat pump system with the function of increasing gas injection enthalpy.

[0007] The invention object of the utility model is achieved as follows: a high-temperature heat pump system with an air-increasing spray enthalpy function, comprising a primary heat pump system, a secondary heat pump system, and a water supply system, wherein the water supply system is connected to the primary heat pump system and the secondary heat pump system, wherein the primary heat pump system comprises an enthalpy spray compressor, a four-way valve, a primary heat exchanger, a primary throttle, an evaporator, and a separator connected by a refrigerant pipeline to form a primary refrigerant circulation loop, the secondary heat pump system comprises a secondary economizer, the evaporator is connected to an air-increasing spray enthalpy throttle, and the refrigerant outlet of the evaporator, the air-increasing spray enthalpy throttle, the secondary economizer, and the enthalpy spray port of the enthalpy spray compressor form an intake circuit.

[0008] According to the above optimization, the spray enthalpy compressor is set as a DC variable frequency spray enthalpy compressor.

[0009] According to the above optimization, the gas injection enthalpy throttle is set as a gas injection enthalpy electronic expansion valve.

[0010] According to the above optimization, an intermediate heat exchanger is provided between the primary heat pump system and the secondary heat pump system, and the first refrigerant inlet and the first refrigerant outlet of the intermediate heat exchanger are respectively connected to the refrigerant outlet end of the four-way valve and the refrigerant inlet of the primary heat exchanger, and the second refrigerant inlet and the second refrigerant outlet of the intermediate heat exchanger are respectively connected to the refrigerant outlet of the secondary economizer and the refrigerant inlet end of the secondary heat pump system.

[0011] According to the above optimization, the secondary heat pump system also includes a secondary compressor, a secondary water-side heat exchanger, and a secondary throttle. The secondary compressor, secondary water-side heat exchanger, secondary economizer, secondary throttle, and intermediate heat exchanger are connected through a refrigerant pipe to form a secondary refrigerant circulation loop.

[0012] According to the above optimization, the two-stage compressor is set as a fixed-frequency compressor.

[0013] According to the above optimization, the secondary throttle is set as a secondary electronic expansion valve.

[0014] The advantages of the utility model are:

[0015] 1) An air intake circuit is formed through the refrigerant outlet of the evaporator, the air injection enthalpy throttle, the secondary economizer, and the injection enthalpy port of the injection enthalpy compressor. The air intake circuit is used to upgrade the compression process of the injection enthalpy compressor from only one time to two times, thereby increasing the refrigerant circulation volume, and improving the subcooling degree of the refrigerant entering the injection enthalpy compressor through the secondary economizer, thereby improving the system capacity to adapt to normal operation in ultra-low temperature environment.

[0016] 2) By adopting a DC variable frequency compressor, the operation is stable, the heating efficiency is improved, the energy attenuation is reduced, the energy efficiency ratio is improved, and the operating cost can be saved.

[0017] 3) Under the action of the intermediate heat exchanger, the low-grade heat of the primary heat pump system is used as production heat and transferred to the secondary heat pump system, which can improve the energy efficiency of the primary heat pump system. Under the cascade effect of the two-stage heat pump system, the heating energy efficiency is greatly improved, and high-temperature hot water can be continuously produced in a low-temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a working principle diagram of a preferred embodiment of the utility model. DETAILED DESCRIPTION

[0019] The utility model is further described below in conjunction with the accompanying drawings.

[0020] According to the attached Figure 1As shown, the high-temperature heat pump system with the function of increasing air enthalpy injection of the utility model comprises a primary heat pump system, a secondary heat pump system, and a water supply system, wherein the water supply system is connected to the primary heat pump system and the secondary heat pump system. The primary heat pump system comprises an injection enthalpy compressor 1, a four-way valve 2, a primary heat exchanger 3, a primary throttle 4, an evaporator 5, and a separator 6 connected by a refrigerant pipeline to form a primary refrigerant circulation loop. The secondary heat pump system comprises a secondary economizer 9, and the evaporator 5 is connected to an air-increasing injection enthalpy throttle 11, and the refrigerant outlet of the evaporator 5, the air-increasing injection enthalpy throttle 11, the secondary economizer 9, and the injection enthalpy port of the injection enthalpy compressor 1 form an air intake loop.

[0021] During operation, the spray enthalpy compressor 1 compresses the refrigerant into high-pressure and high-temperature refrigerant gas, which is transported from the outlet of the spray enthalpy compressor 1 through the four-way valve 2 to the primary heat exchanger 3, so that the high-pressure and high-temperature refrigerant gas undergoes heat exchange in the primary heat exchanger 3, thereby obtaining high-temperature hot water. Then, a part of the condensed refrigerant is transported to the evaporator 5, the four-way valve 2, the separator 6 in turn through the primary throttle 4 and returns to the spray enthalpy compressor 1 through the return air port of the spray enthalpy compressor 1 to perform the next cycle compression work; during this period, another part of the condensed refrigerant passes through the refrigerant outlet of the evaporator 5 and passes through the gas-increasing spray enthalpy throttle 11 and the secondary economizer 9 in turn, so that the refrigerant is once again supercooled in the secondary economizer 9, improving the system capacity so that it can still operate normally in an ultra-low temperature environment. Then, the supercooled refrigerant is replenished into the spray enthalpy compressor 1 through the spray enthalpy port of the spray enthalpy compressor 1, so that the compressor compression process is upgraded to two times, the refrigerant circulation volume is increased, and the heating capacity is increased.

[0022] The enthalpy injection compressor 1 is a DC variable frequency enthalpy injection compressor 1. The air-increasing enthalpy injection throttle 11 is an air-increasing enthalpy injection electronic expansion valve. This effectively stabilizes the operation of the heat pump system, improves heating efficiency, reduces energy attenuation, improves energy efficiency, and saves operating costs.

[0023] Reference Figure 1 As shown, in further detail, an intermediate heat exchanger 12 is provided between the primary heat pump system and the secondary heat pump system, and the first refrigerant inlet and the first refrigerant outlet of the intermediate heat exchanger 12 are respectively connected to the refrigerant outlet end of the four-way valve 2 and the refrigerant inlet of the primary heat exchanger 3, and the second refrigerant inlet and the second refrigerant outlet of the intermediate heat exchanger 12 are respectively connected to the refrigerant outlet of the secondary economizer 9 and the refrigerant inlet end of the secondary heat pump system.

[0024] Among them, the secondary heat pump system also includes a secondary compressor 7, a secondary water-side heat exchanger 8, and a secondary throttle 10. The secondary compressor 7, the secondary water-side heat exchanger 8, the secondary economizer 9, the secondary throttle 10, and the intermediate heat exchanger 12 are connected through a refrigerant pipe to form a secondary refrigerant circulation loop.

[0025] During operation, the secondary compressor 7 generates a high-temperature and high-pressure refrigerant airflow which is transported to the secondary water-side heat exchanger 8 for heat exchange to obtain high-temperature hot water. After condensation, the refrigerant is output to the economizer, where it undergoes heat exchange with the suction circuit. After another heat exchange, it is sequentially transported to the secondary throttle 10 and the intermediate heat exchanger 12. At this time, the refrigerant is transported back to the secondary compressor 7 after multiple heat exchanges, effectively preventing high-temperature non-condensable refrigerant from being output to the compressor, thereby improving system capacity and ensuring normal operation in ultra-low temperature environments.

[0026] At the same time, under the action of the intermediate heat exchanger 12, the low-grade heat of the first-stage heat pump system is used as production heat and transferred to the second-stage heat pump system, which can improve the energy efficiency of the first-stage heat pump system. Under the cascading effect of the two-stage heat pump system, the heating energy efficiency is greatly improved, and high-temperature hot water can be continuously produced in a low-temperature environment.

[0027] In practical applications, the secondary compressor 7 is set as a fixed frequency compressor, and the secondary throttle 10 is set as a secondary electronic expansion valve, which can improve the operation stability of the heat pump system, increase the heating efficiency, and save operating costs.

[0028] The above-mentioned specific embodiments are only specific implementation methods with better effects of the utility model. Any structure that is the same or equivalent to the high-temperature heat pump system with the function of increasing gas injection enthalpy of the utility model is within the protection scope of the utility model.

Claims

1. A high-temperature heat pump system with an air injection enthalpy increasing function, comprising a primary heat pump system, a secondary heat pump system, and a water supply system, wherein the water supply system is connected to the primary heat pump system and the secondary heat pump system, and is characterized in that: The primary heat pump system comprises an enthalpy spray compressor (1), a four-way valve (2), a primary heat exchanger (3), a primary throttle (4), an evaporator (5), and a separator (6) which are connected through a refrigerant pipeline to form a primary refrigerant circulation loop; the secondary heat pump system comprises a secondary economizer (9); the evaporator (5) is connected to an air-increasing enthalpy spray throttle (11); the refrigerant outlet of the evaporator (5), the air-increasing enthalpy spray throttle (11), the secondary economizer (9), and the enthalpy spray port of the enthalpy spray compressor (1) form an air intake loop.

2. The high-temperature heat pump system with the function of increasing gas injection enthalpy according to claim 1, characterized in that: The spray enthalpy compressor (1) is configured as a DC variable frequency spray enthalpy compressor (1).

3. The high temperature heat pump system with the function of increasing gas injection enthalpy according to claim 1, characterized in that: The gas-increasing enthalpy injection throttle (11) is configured as a gas-increasing enthalpy injection electronic expansion valve.

4. The high-temperature heat pump system with the function of increasing gas injection enthalpy according to claim 1, characterized in that: An intermediate heat exchanger (12) is provided between the primary heat pump system and the secondary heat pump system. The first refrigerant inlet and the first refrigerant outlet of the intermediate heat exchanger (12) are respectively connected to the refrigerant outlet end of the four-way valve (2) and the refrigerant inlet end of the primary heat exchanger (3). The second refrigerant inlet and the second refrigerant outlet of the intermediate heat exchanger (12) are respectively connected to the refrigerant outlet end of the secondary economizer (9) and the refrigerant inlet end of the secondary heat pump system.

5. The high temperature heat pump system with the function of increasing the gas injection enthalpy according to claim 4, characterized in that: The two-stage heat pump system further comprises a two-stage compressor (7), a two-stage water-side heat exchanger (8), and a two-stage throttle (10); the two-stage compressor (7), the two-stage water-side heat exchanger (8), the two-stage economizer (9), the two-stage throttle (10), and the intermediate heat exchanger (12) are connected via a refrigerant pipe to form a two-stage refrigerant circulation loop.

6. The high temperature heat pump system with the function of increasing the gas injection enthalpy according to claim 5, characterized in that: The secondary compressor (7) is configured as a fixed-frequency compressor.

7. The high temperature heat pump system with the function of increasing the gas injection enthalpy according to claim 5, characterized in that: The secondary throttle (10) is configured as a secondary electronic expansion valve.

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