Direct-current variable-frequency high-temperature heat pump system
By adopting a DC variable frequency high-temperature heat pump system in the air source heat pump system, and using intermediate heat exchangers and refrigerant storage circulation and other technical means, the problem of insufficient heating capacity in the low-temperature environment in the existing technology is solved, and the low-temperature environment is realized High temperature hot water supply and system performance improvements.
Patent Information
- Application Number
- CN202421116622.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-21
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-05-21
AI Technical Summary
The existing air source heat pump system lacks heating capacity in low temperature environments, resulting in insufficient hot water temperature, complex system structure, low energy utilization, high manufacturing cost, and insufficient capacity can still occur in ultra-low temperature environments.
The DC variable frequency high temperature heat pump system is adopted, including the first-level heat pump system, the second-level heat pump system and the water supply system. The low-grade heat of the first-level heat pump system is transferred to the second-level heat pump system through an intermediate heat exchanger, and the refrigerant storage circulation is divided into the refrigerant storage cycle and With the cooperation of jet enthalpy circuit, heating energy efficiency and system performance are improved.
It can continuously produce high-temperature hot water in a low-temperature environment, which improves heating energy efficiency and system performance, adapts to normal operation in ultra-low-temperature environments, and reduces operating costs.
Smart Images
Figure CN222480819U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of heat pumps, in particular to a direct current variable frequency high-temperature heat pump system. 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, high manufacturing cost, and insufficient capacity in ultra-low temperature environment, which affects the user experience. Utility Model Content
[0006] The utility model aims to solve the shortcomings in the prior art and proposes a DC variable frequency high temperature heat pump system.
[0007] The invention objective of the utility model is achieved as follows: a DC variable frequency high-temperature heat pump system, comprising a primary heat pump system, a secondary heat pump system, and a water supply system, wherein the water supply system is respectively connected to the primary heat pump system and the secondary heat pump system, wherein an intermediate heat exchanger is connected between the primary heat pump system and the secondary heat pump system, which can cascade the two-stage heat pump systems and transfer the heat absorbed by the primary heat pump system to the secondary heat pump system, the intermediate heat exchanger is connected to a refrigerant storage circulation branch for storing part of the refrigerant for the primary heat pump system, the refrigerant circulation branch is connected to the primary heat pump system, the primary heat pump system is connected to a jet reheat increase circuit, and the secondary heat pump system is equipped with an economizer for subcooling heat exchange with the jet reheat increase circuit.
[0008] According to the above optimization, the primary heat pump system includes an enthalpy spray compressor, a four-way valve, a primary heat exchanger, a primary main electronic expansion valve, an evaporation component, and a separator. The exhaust port of the enthalpy spray compressor, the four-way valve, the intermediate heat exchanger, the primary heat exchanger, the primary main electronic expansion valve, the evaporation component, the separator, and the return air port of the enthalpy spray compressor are connected in sequence through a refrigerant conduit to form a primary refrigerant circulation main circuit for circulating refrigerant; the primary refrigerant circulation main circuit is connected to a refrigerant storage circulation branch, and the water inlet pipe and the water outlet pipe of the water supply system are respectively connected to the water inlet and the water outlet of the primary heat exchanger.
[0009] According to the above optimization, the refrigerant storage circulation branch includes a first one-way valve and a second one-way valve. The refrigerant inlet end of the first one-way valve is connected to the intermediate heat exchanger and the refrigerant output end of the second one-way valve through a refrigerant conduit, and the refrigerant output end of the first one-way valve is connected to the refrigerant inlet end of the primary heat exchanger, the evaporation component, and the primary main electronic expansion valve through a refrigerant conduit.
[0010] According to the above optimization, the primary heat exchanger is configured as a heat exchanger with a balancer.
[0011] According to the above optimization, the evaporation component includes a fin-type heat exchanger with a fan, and the refrigerant inlet end and the refrigerant output end of the fin-type heat exchanger are respectively connected to the primary main electronic expansion valve and the four-way valve through the refrigerant conduit, and the fin-type heat exchanger is installed with a subcooling heat exchanger for heat exchange with it, and the subcooling heat exchanger is connected to the jet enthalpy increase circuit.
[0012] According to the above optimization, the jet enthalpy increase circuit includes a first-stage auxiliary electronic expansion valve, the refrigerant inlet end of the first-stage auxiliary electronic expansion valve is connected to the subcooling heat exchanger through a refrigerant conduit, the refrigerant output end of the first-stage auxiliary electronic expansion valve is connected to the first refrigerant inlet end of the economizer through the refrigerant conduit, and the first refrigerant output end of the economizer is connected to the jet enthalpy port of the jet compressor through the refrigerant conduit.
[0013] According to the above optimization, the spray enthalpy compressor is set as a DC variable frequency spray enthalpy compressor.
[0014] According to the above optimization, the secondary heat pump system includes a secondary compressor, a secondary water-side heat exchanger, and a secondary main electronic expansion valve. The exhaust port of the secondary compressor, the secondary water-side heat exchanger, the economizer, the secondary main electronic expansion valve, the intermediate heat exchanger, and the air inlet of the secondary compressor are connected through a refrigerant conduit to form a secondary refrigerant circulation main circuit; the water inlet pipe and the water outlet pipe of the water supply system are respectively connected to the water inlet and the water outlet of the secondary water-side heat exchanger.
[0015] According to the above optimization, the two-stage compressor is set as a fixed-frequency compressor.
[0016] The advantages of the utility model are:
[0017] 1) 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.
[0018] 2) By adding a refrigerant storage circulation branch, part of the refrigerant can be stored, and all the refrigerant can be involved in the heat exchange process, so that the high-temperature and high-pressure gas pressure refrigerant can exchange heat with the water in the first-stage heat exchanger, making full use of the latent heat released by the refrigerant, and at the same time further supercooling the gas-liquid reflux refrigerant, thereby improving the evaporation effect, increasing the operating stability, improving the system performance, and ensuring the continuous output of high-temperature hot water.
[0019] 3) By utilizing the suction circuit, the compression process of the spray compressor is upgraded from one time to two times, increasing the refrigerant circulation volume, and the subcooling degree of the spray compressor refrigerant entering the primary heat pump system is improved through the economizer, thereby improving the system capacity to adapt to normal operation in ultra-low temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a working principle diagram of a preferred embodiment of the utility model. DETAILED DESCRIPTION
[0021] The utility model is further described below in conjunction with the accompanying drawings.
[0022] According to the attached Figure 1 As shown, the DC variable frequency high temperature heat pump system of the utility model comprises a primary heat pump system, a secondary heat pump system, and a water supply system 15, wherein the water supply system 15 is connected to the primary heat pump system and the secondary heat pump system, respectively. Among them, an intermediate heat exchanger 3 is connected between the primary heat pump system and the secondary heat pump system, which can cascade the two-stage heat pump system and transfer the heat absorbed by the primary heat pump system to the secondary heat pump system, and the intermediate heat exchanger 3 is connected to a refrigerant storage circulation branch for storing part of the refrigerant in the primary heat pump system, and the refrigerant circulation branch is connected to the primary heat pump system, the primary heat pump system is connected to a jet enthalpy increase circuit, and the secondary heat pump system is equipped with an economizer 13 for subcooling heat exchange with the jet enthalpy increase circuit.
[0023] Under the action of the intermediate heat exchanger 3, 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.
[0024] Reference Figure 1As shown, in further detail, the primary heat pump system includes an enthalpy spray compressor 1, a four-way valve 2, a primary heat exchanger 4, a primary main circuit electronic expansion valve 5, an evaporation component 6, and a separator 7. The exhaust port of the enthalpy spray compressor 1, the four-way valve 2, the intermediate heat exchanger 3, the primary heat exchanger 4, the primary main circuit electronic expansion valve 5, the evaporation component 6, the separator 7, and the return air port of the enthalpy spray compressor 1 are connected in sequence through a refrigerant conduit to form a primary refrigerant circulation main circuit for circulating refrigerant. The primary refrigerant circulation main circuit is connected to a refrigerant storage circulation branch, and the water inlet pipe and the water outlet pipe of the water supply system 15 are respectively connected to the water inlet and the water outlet of the primary heat exchanger 4.
[0025] The refrigerant storage circulation branch includes a first one-way valve 8 and a second one-way valve 9. The refrigerant inlet end of the first one-way valve 8 is connected to the intermediate heat exchanger 3 and the refrigerant outlet end of the second one-way valve 9 through a refrigerant conduit, and the refrigerant outlet end of the first one-way valve 8 is connected to the refrigerant inlet end of the primary heat exchanger 4, the evaporation component 6, and the primary main electronic expansion valve 5 through a refrigerant conduit.
[0026] During operation, the primary heat pump system absorbs heat from the air through the evaporation component 6, and transfers it to the secondary heat pump system via the intermediate heat exchanger 3. The primary heat exchanger 4 of the primary heat pump system and the water-side heat exchanger of the secondary heat pump system then exchange heat with the water in the water supply system 15, thereby achieving low-temperature or high-temperature water supply.
[0027] During this period, part of the refrigerant in the primary refrigerant circulation main circuit will flow along the refrigerant storage circulation branch circuit to the primary heat exchanger 4 for heat exchange again. That is, after the refrigerant of the primary heat pump system flows out from the intermediate heat exchanger 3, part of the refrigerant will directly flow to the evaporator component 6, and part of the refrigerant will continue to flow to the primary heat exchanger 4 through the first one-way valve 8, so that heat exchange can be carried out with the water in the primary heat exchanger 4 to produce low-temperature hot water, and then the refrigerant after heat exchange can be mixed with the refrigerant in the primary refrigerant circulation main circuit through the second one-way valve 9 and the first one-way valve 8 and diverted to the primary heat exchanger 4 and the evaporator component 6 again.
[0028] In this way, by adding a refrigerant storage circulation branch, part of the refrigerant can be stored, and all the refrigerant can be involved in the heat exchange process, so that the high-temperature and high-pressure gas pressure refrigerant can exchange heat with the water in the first-stage heat exchanger 4, fully utilizing the latent heat released by the refrigerant, and at the same time further supercooling the gas-liquid reflux refrigerant, thereby enhancing the evaporation effect, increasing the operating stability, improving the system performance, and ensuring the continuous output of high-temperature hot water.
[0029] In addition, the primary heat exchanger 4 is configured as a heat exchanger with a balancer, which effectively controls the balance of refrigerant energy, improves heat exchange efficiency, and enhances system performance.
[0030] Reference Figure 1As shown, in further detail, the evaporation assembly 6 includes a finned heat exchanger 61 with a fan 62, and the refrigerant inlet end and the refrigerant outlet end of the finned heat exchanger 61 are respectively connected to the primary main circuit electronic expansion valve 5 and the four-way valve 2 through the refrigerant conduit. The finned heat exchanger 61 is installed with a subcooling heat exchanger 63 for heat exchange with it, and the subcooling heat exchanger 63 is connected to the jet enthalpy increase circuit.
[0031] Among them, the jet enthalpy increase circuit includes a first-stage auxiliary electronic expansion valve 10, the refrigerant inlet end of the first-stage auxiliary electronic expansion valve 10 is connected to the subcooling heat exchanger 63 through a refrigerant conduit, the refrigerant output end of the first-stage auxiliary electronic expansion valve 10 is connected to the first refrigerant inlet end of the economizer 13 through a refrigerant conduit, and the first refrigerant output end of the economizer 13 is connected to the jet enthalpy port of the jet compressor 1 through the refrigerant conduit.
[0032] During operation, the spray enthalpy compressor 1 compresses the refrigerant into high-pressure and high-temperature refrigerant gas, which is transported from the exhaust port of the spray enthalpy compressor 1 through the four-way valve 2 to the intermediate heat exchanger 3 and the primary heat exchanger 4, so that the high-pressure and high-temperature refrigerant gas transfers heat to the secondary heat pump system through the intermediate heat exchanger 3, and then part of the refrigerant is transferred to the primary heat exchanger 4 for heat exchange, thereby obtaining high-temperature hot water. Subsequently, part of the condensed refrigerant is transported to the finned heat exchanger 61, the four-way valve 2, the separator 7 in sequence through the primary main electronic expansion valve 5 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 is transported to the jet enthalpy increase circuit through the refrigerant conduit, that is, part of the refrigerant flows to the supercooling heat exchanger 63, and evaporates and exchanges heat on the supercooling heat exchanger 63. The fan 62 is used to fully absorb the heat of the air, and at the same time, the finned heat exchanger 61 can be preheated to improve the heating capacity, effectively prevent freezing and ice, improve energy efficiency, and have low cost of use, which is suitable for ultra-low temperature use. Subsequently, the refrigerant after heat exchange passes through the primary secondary electronic expansion valve 10 and the economizer 13, so that the refrigerant is once again supercooled in the economizer 13, and the system capacity is improved to adapt to normal operation in an ultra-low temperature environment. Finally, the supercooled refrigerant is added to the jet enthalpy compressor 1 through the jet enthalpy port of the jet enthalpy compressor 1, so that the compressor compression process is upgraded to twice, the refrigerant circulation volume is increased, and the heating capacity is increased.
[0033] Moreover, the enthalpy injection compressor 1 is set as a DC variable frequency enthalpy injection compressor 11. This effectively stabilizes the operation of the heat pump system, improves heating efficiency, reduces energy attenuation, improves energy efficiency, and saves operating costs.
[0034] Reference Figure 1As shown, in further detail, the secondary heat pump system includes a secondary compressor 11, a secondary water-side heat exchanger 12, and a secondary main electronic expansion valve 14. The exhaust port of the secondary compressor 11, the secondary water-side heat exchanger 12, the economizer 13, the secondary main electronic expansion valve 14, the intermediate heat exchanger 3, and the air inlet of the secondary compressor 11 are connected through a refrigerant conduit to form a secondary refrigerant circulation main circuit; the water inlet pipe and the water outlet pipe of the water supply system 15 are respectively connected to the water inlet and the water outlet of the secondary water-side heat exchanger 12.
[0035] During operation, the secondary compressor 11 generates a high-temperature and high-pressure refrigerant gas flow which is transported to the secondary water-side heat exchanger 12 for heat exchange to obtain high-temperature hot water. After condensation, the refrigerant is output to the economizer 13, where it undergoes heat exchange with the suction circuit again. After another heat exchange, it is sequentially transported to the secondary main electronic expansion valve 14 and the intermediate heat exchanger 3. At this point, the refrigerant is transported back to the secondary compressor 11 after multiple heat exchanges, effectively preventing high-temperature non-condensable refrigerant from being output to the compressor, improving system capacity, and ensuring normal operation in ultra-low temperature environments.
[0036] At the same time, under the action of the intermediate heat exchanger 3, the low-grade heat of the primary heat pump system is used as production heat and transferred to the secondary heat pump system, which greatly improves the heating efficiency and realizes the continuous production of high-temperature hot water in a low-temperature environment.
[0037] In practical applications, the secondary compressor 11 is set as a fixed-frequency compressor, which can improve the operation stability of the heat pump system, increase the heating efficiency, and save operating costs.
[0038] The above specific embodiments are only specific implementation methods with better effects of the utility model. Any structure that is the same or equivalent to the DC variable frequency high-temperature heat pump system of the utility model is within the protection scope of the utility model.
Claims
1. A DC variable frequency high temperature heat pump system, comprising a primary heat pump system, a secondary heat pump system, and a water supply system (15), wherein the water supply system (15) is connected to the primary heat pump system and the secondary heat pump system, respectively, and characterized in that: An intermediate heat exchanger (3) is connected between the primary heat pump system and the secondary heat pump system, which can cascade the two-stage heat pump systems and transfer the heat absorbed by the primary heat pump system to the secondary heat pump system. The intermediate heat exchanger (3) is connected to a refrigerant storage circulation branch for storing part of the refrigerant in the primary heat pump system. The refrigerant circulation branch is connected to the primary heat pump system. The primary heat pump system is connected to an injection enthalpy increase circuit. The secondary heat pump system is equipped with an economizer (13) for subcooling heat exchange with the injection enthalpy increase circuit.
2. The DC variable frequency high temperature heat pump system according to claim 1, characterized in that: The primary heat pump system comprises an enthalpy spray compressor (1), a four-way valve (2), a primary heat exchanger (4), a primary main circuit electronic expansion valve (5), an evaporation component (6), and a separator (7); the exhaust port of the enthalpy spray compressor (1), the four-way valve (2), the intermediate heat exchanger (3), the primary heat exchanger (4), the primary main circuit electronic expansion valve (5), the evaporation component (6), the separator (7), and the return air port of the enthalpy spray compressor (1) are connected in sequence through a refrigerant conduit to form a primary refrigerant circulation main circuit for circulating refrigerant; the primary refrigerant circulation main circuit is connected to a refrigerant storage circulation branch circuit, and the water inlet pipe and the water outlet pipe of the water supply system (15) are respectively connected to the water inlet and the water outlet of the primary heat exchanger (4).
3. The DC variable frequency high temperature heat pump system according to claim 2, characterized in that: The refrigerant storage circulation branch comprises a first one-way valve (8) and a second one-way valve (9); the refrigerant inlet end of the first one-way valve (8) is connected to the intermediate heat exchanger (3) and the refrigerant outlet end of the second one-way valve (9) respectively through a refrigerant conduit; the refrigerant outlet end of the first one-way valve (8) is connected to the refrigerant inlet end of the primary heat exchanger (4), the evaporation component (6), and the primary main circuit electronic expansion valve (5) respectively through a refrigerant conduit.
4. The DC variable frequency high temperature heat pump system according to claim 2 or 3, characterized in that: The primary heat exchanger (4) is configured as a heat exchanger with a balancer.
5. The DC variable frequency high temperature heat pump system according to claim 2, characterized in that: The evaporation component (6) includes a finned heat exchanger (61) with a fan (62); the refrigerant inlet end and the refrigerant outlet end of the finned heat exchanger (61) are respectively connected to the primary main circuit electronic expansion valve (5) and the four-way valve (2) through a refrigerant conduit; the finned heat exchanger (61) is equipped with a subcooling heat exchanger (63) for heat exchange with the finned heat exchanger; the subcooling heat exchanger (63) is connected to the jet enthalpy increase circuit.
6. The DC variable frequency high temperature heat pump system according to claim 1 or 5, characterized in that: The jet enthalpy increase circuit comprises a primary auxiliary electronic expansion valve (10), a refrigerant inlet end of the primary auxiliary electronic expansion valve (10) is connected to a subcooling heat exchanger (63) via a refrigerant conduit, a refrigerant output end of the primary auxiliary electronic expansion valve (10) is connected to a first refrigerant inlet end of an economizer (13) via a refrigerant conduit, and a first refrigerant output end of the economizer (13) is connected to a jet enthalpy port of the jet compressor (1) via a refrigerant conduit.
7. The DC variable frequency high temperature heat pump system according to claim 2, characterized in that: The spray enthalpy compressor (1) is configured as a DC variable frequency spray enthalpy compressor (1).
8. The DC variable frequency high temperature heat pump system according to claim 1, characterized in that: The secondary heat pump system comprises a secondary compressor (11), a secondary water-side heat exchanger (12), and a secondary main electronic expansion valve (14); the exhaust port of the secondary compressor (11), the secondary water-side heat exchanger (12), the economizer (13), the secondary main electronic expansion valve (14), the intermediate heat exchanger (3), and the air inlet of the secondary compressor (11) are connected via a refrigerant conduit to form a secondary refrigerant circulation main circuit; the water inlet pipe and the water outlet pipe of the water supply system (15) are respectively connected to the water inlet and the water outlet of the secondary water-side heat exchanger (12).
9. The DC variable frequency high temperature heat pump system according to claim 8, characterized in that: The secondary compressor (11) is configured as a fixed-frequency compressor.