阅读说明：本技术 一种可单级运行复叠式冷热水热泵系统 (Cascade type cold and hot water heat pump system capable of operating at single stage ) 是由 蔡佰明 黄剑峰 劳焯明 于 2020-05-29 设计创作，主要内容包括：本发明提供一种可单级运行复叠式冷热水热泵系统,其包括低温级热泵部件、高温级热泵部件、耗能末端,低温级热泵部件的低温级压缩机、低温四通阀、冷凝蒸发换热器、低温级水氟换热器、室外翅片换热器、低温级气液分离器相能以形成有低温级冷媒循环路径,高温级热泵部件的高温级压缩机、高温级四通阀、高温级水氟换热器、高温级经济器、冷凝蒸发换热器、高温级气液分离器连通以形成有高温级冷媒循环路径,利用高温级经济器分别与中间喷气回路、低温级压缩机的喷焓口连通,装配简单,且具有单独运行低温级用于制热或制冷的功能,提高在低温度环境下的换热效能,保证热泵系统的使用质量。(The invention provides a cascade type cold and hot water heat pump system capable of single-stage operation, which comprises a low-temperature stage heat pump component, a high-temperature stage heat pump component and an energy consumption tail end, wherein a low-temperature stage compressor, a low-temperature four-way valve, a condensation evaporation heat exchanger, a low-temperature stage water fluorine heat exchanger, an outdoor fin heat exchanger and a low-temperature stage gas-liquid separator of the low-temperature stage heat pump component can form a low-temperature stage refrigerant circulation path, a high-temperature stage compressor, a high-temperature stage four-way valve, a high-temperature stage water fluorine heat exchanger, a high-temperature stage economizer, a condensation evaporation heat exchanger and a high-temperature stage gas-liquid separator of the high-temperature stage heat pump component are communicated to form a high-temperature stage refrigerant circulation path, the high-temperature stage economizer is respectively communicated with an intermediate air injection loop and an enthalpy injection port of the low, the use quality of the heat pump system is ensured.)

1. The utility model provides a but single-stage operation cascade hot and cold water heat pump system which characterized in that: the heat pump system comprises a low-temperature-level heat pump component, a high-temperature-level heat pump component and an energy consumption tail end (1), wherein the low-temperature-level heat pump component comprises a low-temperature-level compressor (2), a low-temperature four-way valve (3), a condensation evaporation heat exchanger (4), a low-temperature-level water-fluorine heat exchanger (5), an outdoor finned heat exchanger (6) and a low-temperature-level gas-liquid separator (7) which are connected through a low-temperature-level pipeline to form a low-temperature-level,

the low-temperature stage compressor (2) is provided with an enthalpy injection port, an intermediate air injection loop is arranged between the enthalpy injection port and a liquid inlet of the outdoor fin heat exchanger (6), the intermediate air injection loop is provided with an enhanced vapor injection solenoid valve (8), a high-temperature stage economizer (9) communicated through an enhanced vapor pipeline is arranged at an inlet port and an outlet port of the enhanced vapor injection solenoid valve (8),

the high-temperature-stage heat pump component comprises a high-temperature-stage compressor (10), a high-temperature-stage four-way valve (11), a high-temperature-stage water-fluorine heat exchanger (12) and a high-temperature-stage gas-liquid separator (13), wherein the high-temperature-stage compressor (10), the high-temperature-stage four-way valve (11), the high-temperature-stage water-fluorine heat exchanger (12), a high-temperature-stage economizer (9), a condensation evaporation heat exchanger (4) and the high-temperature-stage gas-liquid separator (13) are communicated through a high-temperature.

2. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 1, wherein: the middle air injection loop comprises a first check valve (14), a second check valve (15), a third check valve (16), a fourth check valve (17), a low-temperature-level economizer (18) and an enhanced vapor injection throttle valve (19), wherein liquid inlet ends of the first check valve (14) and the second check valve (15) are communicated with liquid outlet ends of the third check valve (16) and the fourth check valve (17), a first interface of the low-temperature-level economizer (18) is communicated with liquid outlet ends of the first check valve (14) and the second check valve (15), a second interface of the low-temperature-level economizer (18) is communicated with a liquid inlet of the enhanced vapor injection throttle valve (19), liquid inlet ends of the third check valve (16) and the fourth check valve (17), a liquid outlet of the enhanced vapor injection throttle valve (19) is communicated with a third interface of the low-temperature-level economizer (18), and a fourth interface of the low-temperature-level economizer (18) is communicated with a high-temperature-level economizer (9) respectively, The enhanced vapor injection electromagnetic valve (8) is communicated.

3. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 2, wherein: a second interface of the low-temperature-level economizer (18) is communicated with a low-temperature-level throttling valve (37), the low-temperature-level throttling valve (37) is respectively communicated with liquid inlet ends of a third one-way valve (16) and a fourth one-way valve (17), and a liquid outlet end of the fourth one-way valve (17) is sequentially communicated with a liquid storage tank (38), a first drying filter (39) and a low-temperature-level water-fluorine heat exchanger (5); and the liquid outlet end of the third one-way valve (16) is communicated with a second drying filter (40) which is connected with the outdoor fin heat exchanger (6).

4. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 2, wherein: the condensation evaporation heat exchanger (4) is communicated with a high-temperature throttling valve (20) and a refrigerant migration prevention electromagnetic valve (21) between the connection of a first interface of the high-temperature economizer (9), a third drying filter (22) is communicated between a second interface of the high-temperature economizer (9) and the connection of the high-temperature water-fluorine heat exchanger (12), and a third interface and a fourth interface of the high-temperature economizer (9) are respectively communicated with a fourth interface of the low-temperature economizer (18) and an enthalpy spraying port of the low-temperature compressor (2).

5. The cascade-type heat and cold water heat pump system capable of single-stage operation according to any one of claims 1 to 4, wherein: the heat pump system further comprises an energy storage buffer water tank (23), a low-temperature-level water pump (24) and a circulating water pump (25), wherein the energy storage buffer water tank (23) is provided with a liquid supply pipeline (26) and a liquid return pipeline (27), the liquid supply pipeline (26) communicates an energy consumption tail end (1), the energy storage buffer water tank (23), the high-temperature-level water-fluorine heat exchanger (12) and the circulating water pump (25) and is formed with an energy storage circulating path, and the liquid return pipeline (27) communicates the energy storage buffer water tank (23), the low-temperature-level water-fluorine heat exchanger (5) and the low-temperature-level water pump (24) and forms a.

6. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 5, wherein: the energy consumption tail end (1) is provided with a water outlet (28) and a water return port (29), and the water outlet (28) and the water return port (29) are respectively communicated with the energy storage buffer water tank (23) and the high-temperature-level water-fluorine heat exchanger (12) through a liquid supply pipeline (26).

7. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 6, wherein: the energy storage buffer water tank (23) is provided with a liquid storage outer cavity (30) and a liquid storage inner cavity (31), the liquid storage inner cavity (31) is positioned in the middle of the liquid storage outer cavity (30), the upper part and the lower part of the liquid storage inner cavity (31) are respectively communicated with the liquid storage outer cavity (30),

the water outlet (28) of the energy consumption tail end (1) is communicated with the upper part of a liquid storage outer cavity (30) through a liquid supply pipeline (26), the lower part of the liquid storage outer cavity (30) is communicated with the liquid outlet end of a low-temperature-level water pump (24) through a liquid return pipeline (27), the upper part of a liquid storage inner cavity (31) is communicated with the liquid inlet end of a low-temperature-level water-fluorine heat exchanger (5) through the liquid return pipeline (27), and the lower part of the liquid storage inner cavity (31) is communicated with the liquid inlet end of a circulating water pump (25) through the liquid supply pipeline (26).

8. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 7, wherein: the energy storage buffer water tank (23) is provided with an electric heating pipe (32), the electric heating pipe (32) is connected with a first temperature sensor (33) and a second temperature sensor (34) in a signal mode, the first temperature sensor (33) and the electric heating pipe (32) are installed in the liquid storage outer cavity (30) respectively, and the second temperature sensor (34) is installed in a box body of the heat pump system.

9. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 8, wherein: and a water outlet (28) of the energy consumption tail end (1) is provided with a third temperature sensor (35) connected with the low-temperature-level water pump (24) and the electric heating pipe (32), and a fourth temperature sensor (36) connected with the circulating water pump (25) and the electric heating pipe (32) is arranged at the liquid inlet end of the circulating water pump (25).

10. The cascade-type heat and cold water heat pump system capable of single-stage operation according to claim 9, wherein: an anti-freezing temperature controller (41) is installed in the box body of the heat pump system, and the anti-freezing temperature controller (41) is respectively in signal connection with the electric heating pipe (32).

Technical Field

The invention relates to the technical field of heat pump systems, in particular to a cascade type cold and hot water heat pump system capable of operating at a single stage.

Background

Basic principle of the existing heat pump system: the device mainly comprises a compressor, a condenser, an axial fan, an evaporator, a heat preservation water tank, a water pump, a liquid storage tank, a filter, an electronic expansion valve, an electronic automatic controller and the like. After the power is turned on, the axial flow fan starts to operate, outdoor air is subjected to heat exchange through the evaporator, and the air with the reduced temperature is discharged out of the system by the fan. Meanwhile, the working medium in the evaporator absorbs heat to be vaporized and is sucked into the compressor, the compressor compresses the low-pressure working medium gas into high-temperature and high-pressure gas and sends the high-temperature and high-pressure gas into the condenser, water forced to circulate by the water pump also passes through the condenser, is heated by the working medium and then is sent to a user for use, the working medium is cooled into liquid, the liquid flows into the evaporator again after being throttled and cooled by the electronic expansion valve, and the circulation work is repeated. The heat energy in the air is continuously transmitted into the water, so that the water temperature in the heat-insulating water tank is gradually increased, and the water can reach the use temperature suitable for people.

However, the conventional heat pump system described above has the following disadvantages in practical use:

1. the heat-preservation water tank of the traditional heat pump system is difficult to operate on a low-temperature system and a high-temperature system together, and has large use limitation;

2. when a traditional heat pump system operates a low-temperature stage independently for heating or heating, a heat-preservation water tank cannot effectively separate return water at the end of energy consumption from water heated or cooled by the low-temperature stage, so that the temperature of outlet water cannot meet the requirements of people, and the use effect is poor;

3. if the traditional heat pump system has the refrigeration and heating functions, the general structure is complex, the assembly is complex, and the use stability is easily influenced;

4. when the defrosting function of the traditional heat pump system is started, the low-temperature system can consume the heat of the hot water stored in the heat-preservation water tank, so that the use experience of a user can be influenced during defrosting.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a cascade type cold and hot water heat pump system capable of operating at a single stage, which is simple to assemble, has the function of independently operating a low-temperature stage for heating or refrigerating, effectively improves the heat exchange efficiency in a low-temperature environment and ensures the use quality of the heat pump system.

The invention aims to realize the following steps: a cascade type cold and hot water heat pump system capable of single-stage operation comprises a low-temperature-stage heat pump component, a high-temperature-stage heat pump component and an energy consumption tail end, wherein the low-temperature-stage heat pump component comprises a low-temperature-stage compressor, a low-temperature-stage four-way valve, a condensation evaporation heat exchanger, a low-temperature-stage water-fluorine heat exchanger, an outdoor fin heat exchanger and a low-temperature-stage gas-liquid separator which are connected through a low-temperature-stage pipeline to form a low-temperature-,

the low-temperature stage compressor is provided with an enthalpy injection port, an intermediate air injection loop is arranged between the enthalpy injection port and a liquid inlet of the outdoor fin heat exchanger, an enhanced vapor injection solenoid valve is installed on the intermediate air injection loop, a high-temperature stage economizer communicated through an enhanced vapor pipeline is arranged at an inlet port and an outlet port of the enhanced vapor injection solenoid valve,

the high-temperature-stage heat pump component comprises a high-temperature-stage compressor, a high-temperature-stage four-way valve, a high-temperature-stage water-fluorine heat exchanger and a high-temperature-stage gas-liquid separator, wherein the high-temperature-stage compressor, the high-temperature-stage four-way valve, the high-temperature-stage water-fluorine heat exchanger, the high-temperature-stage economizer, the condensation-evaporation heat exchanger and the high-temperature-stage gas-liquid separator are communicated through a high-temperature-stage.

Optimizing according to the aforesaid, middle jet-propelled return circuit is including respectively first check valve, second check valve, third check valve, fourth check valve, low temperature level economic ware, jet enthalpy-increasing choke valve, and the income liquid end of first check valve, second check valve communicates with the play liquid end of third check valve, fourth check valve respectively, the first interface of low temperature level economic ware communicates with the play liquid end of first check valve, second check valve respectively, the second interface of low temperature level economic ware respectively with the inlet of jet enthalpy-increasing choke valve the income liquid end of third check valve, fourth check valve communicates, the liquid outlet of jet enthalpy-increasing choke valve communicates with the third interface of low temperature level economic ware, and the fourth interface of low temperature level economic ware communicates with high temperature level economic ware, jet enthalpy-increasing solenoid valve respectively.

According to the optimization, the second interface of the low-temperature-level economizer is communicated with a low-temperature-level throttling valve, the low-temperature-level throttling valve is respectively communicated with the liquid inlet ends of a third one-way valve and a fourth one-way valve, and the liquid outlet end of the fourth one-way valve is sequentially communicated with a liquid storage tank, a first drying filter and a low-temperature-level water-fluorine heat exchanger; and the liquid outlet end of the third one-way valve is communicated with a second drying filter which is connected with the outdoor fin heat exchanger.

According to the optimization, a high-temperature throttling valve and a refrigerant migration prevention electromagnetic valve are communicated between the connection of the condensation evaporation heat exchanger and the first interface of the high-temperature economizer, a third drying filter is communicated between the connection of the second interface of the high-temperature economizer and the high-temperature water-fluorine heat exchanger, and the third interface and the fourth interface of the high-temperature economizer are respectively communicated with the fourth interface of the low-temperature economizer and an enthalpy spraying port of the low-temperature compressor.

According to the optimization, the heat pump system further comprises an energy storage buffer water tank, a low-temperature-level water pump and a circulating water pump, wherein the energy storage buffer water tank is provided with a liquid supply pipeline and a liquid return pipeline, the liquid supply pipeline communicates the energy consumption tail end, the energy storage buffer water tank, the high-temperature-level water-fluorine heat exchanger and the circulating water pump to form an energy storage circulation path, and the liquid return pipeline communicates the energy storage buffer water tank, the low-temperature-level water-fluorine heat exchanger and the low-temperature-level water pump to form a water return circulation path.

According to the optimization, the energy consumption tail end is provided with a water outlet and a water return port, and the water outlet and the water return port are respectively communicated with the energy storage buffer water tank and the high-temperature-level water-fluorine heat exchanger through a liquid supply pipeline.

According to the optimization, the energy storage buffer water tank is provided with a liquid storage outer cavity and a liquid storage inner cavity, the liquid storage inner cavity is positioned in the middle of the liquid storage outer cavity, the upper part and the lower part of the liquid storage inner cavity are respectively communicated with the liquid storage outer cavity,

the water outlet at the energy consumption tail end is communicated with the upper part of the liquid storage outer cavity through a liquid supply pipeline, the lower part of the liquid storage outer cavity is communicated with the liquid outlet end of the low-temperature-level water pump through a liquid return pipeline, the upper part of the liquid storage inner cavity is communicated with the liquid inlet end of the low-temperature-level water-fluorine heat exchanger through a liquid return pipeline, and the lower part of the liquid storage inner cavity is communicated with the liquid inlet end of the circulating water pump through a liquid supply pipeline.

According to the optimization, the energy storage buffer water tank is provided with the electric heating pipe, the electric heating pipe is connected with the first temperature sensor and the second temperature sensor in a signal mode, the first temperature sensor and the electric heating pipe are installed in the liquid storage outer cavity respectively, and the second temperature sensor is installed in the box body of the heat pump system.

According to the optimization, a third temperature sensor connected with the low-temperature water pump and the electric heating pipe is installed at a water outlet at the energy consumption tail end, and a fourth temperature sensor connected with the circulating water pump and the electric heating pipe is installed at a liquid inlet end of the circulating water pump.

According to the optimization, an anti-freezing temperature controller is installed in the box body of the heat pump system and is in signal connection with the electric heating pipes respectively.

The invention has the advantages that:

1) the heat pump system with the structure has the function of independently operating the low-temperature stage for heating or refrigerating, and has high applicability.

2) The heat pump system of this structure is through addding middle jet-propelled return circuit in low temperature level heat pump unit, and this middle jet-propelled return circuit is connected with high temperature level economic ware to make the displacement that improves low temperature level compressor under low temperature environment, increase the heating capacity, promote heat exchange efficiency, guarantee the heating performance.

3) The heat pump system with the structure adopts the energy storage buffer water tank, utilizes the middle liquid storage inner cavity, effectively separates the return water at the end of energy consumption from the water passing through the low-temperature system, and improves the thermal efficiency.

4) Because the energy consumption tail end of the heat pump system with the structure is provided with the water outlet and the water return port, the refrigeration and heating functions can be covered by utilizing the two interfaces, the applicability is strong, and the assembly is simple.

5) In the defrosting process, the low-temperature system only consumes the heat of the hot water stored in the energy storage buffer water tank, and when the buffer water tank is too low, the electric heating pipe can be opened for assistance, so that the end use experience of a user is not influenced by defrosting.

Drawings

FIG. 1 is a schematic structural diagram of a preferred embodiment of the present invention.

Fig. 2 is a partially enlarged view of the preferred embodiment of the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

Referring to fig. 1 to 2, the cascade type hot and cold water heat pump system capable of single-stage operation according to the present invention includes a low-temperature-stage heat pump component, a high-temperature-stage heat pump component, and an energy consumption terminal 1. The low-temperature-stage heat pump component comprises a low-temperature-stage compressor 2, a low-temperature-stage four-way valve 3, a condensation evaporation heat exchanger 4, a low-temperature-stage water-fluorine heat exchanger 5, an outdoor finned heat exchanger 6 and a low-temperature-stage gas-liquid separator 7, wherein the low-temperature-stage compressor 2, the low-temperature-stage four-way valve 3, the condensation evaporation heat exchanger, the low-temperature-stage water. Wherein the low-temperature stage compressor 2 is provided with an enthalpy injection port. An intermediate air injection loop is arranged between the connection of the enthalpy injection port and the liquid inlet of the outdoor fin heat exchanger 6, an enhanced vapor injection solenoid valve 8 is installed on the intermediate air injection loop, and a high-temperature-level economizer 9 communicated through an enhanced vapor pipeline is arranged at the inlet port and the outlet port of the enhanced vapor injection solenoid valve 8.

And the high-temperature heat pump component comprises a high-temperature compressor 10, a high-temperature four-way valve 11, a high-temperature water-fluorine heat exchanger 12 and a high-temperature gas-liquid separator 13. The high-temperature-stage compressor 10, the high-temperature-stage four-way valve 11, the high-temperature-stage water-fluorine heat exchanger 12, the high-temperature-stage economizer 9, the condensation-evaporation heat exchanger 4 and the high-temperature-stage gas-liquid separator 13 are communicated through high-temperature-stage pipelines to form a high-temperature-stage refrigerant circulation path.

Referring to fig. 1 to 2, in further detail, the intermediate injection circuit includes a first check valve 14, a second check valve 15, a third check valve 16, a fourth check valve 17, a low-temperature stage economizer 18, and an enhanced vapor injection throttle valve 19, respectively. The liquid inlet ends of the first one-way valve 14 and the second one-way valve 15 are respectively communicated with the liquid outlet ends of the third one-way valve 16 and the fourth one-way valve 17, the first interface of the low-temperature-level economizer 18 is respectively communicated with the liquid outlet ends of the first one-way valve 14 and the second one-way valve 15, and the second interface of the low-temperature-level economizer 18 is respectively communicated with the liquid inlet end of the enhanced vapor injection throttle valve 19 and the liquid inlet ends of the third one-way valve 16 and the fourth one-way valve 17. And a liquid outlet of the enhanced vapor injection throttle valve 19 is communicated with a third interface of the low-temperature economizer 18, and a fourth interface of the low-temperature economizer 18 is respectively communicated with the high-temperature economizer 9 and the enhanced vapor injection electromagnetic valve 8.

Furthermore, the second port of the low temperature stage economizer 18 communicates with a low temperature stage throttle valve 37. The low-temperature-stage throttling valve 37 is respectively communicated with the liquid inlet ends of the third one-way valve 16 and the fourth one-way valve 17, and the liquid outlet end of the fourth one-way valve 17 is sequentially communicated with a liquid storage tank 38, a first drying filter 39 and the low-temperature-stage water-fluorine heat exchanger 5; and the liquid outlet end of the third one-way valve 16 is communicated with a second drying filter 40 which is connected with the outdoor fin heat exchanger 6.

In addition, a high-temperature-stage throttle valve 20 and a refrigerant migration prevention electromagnetic valve 21 are communicated between the connection of the condensation-evaporation heat exchanger 4 and the first interface of the high-temperature-stage economizer 9. A third drying filter 22 is communicated between the second interface of the high-temperature-stage economizer 9 and the connection of the high-temperature-stage water-fluorine heat exchanger 12, and the third interface and the fourth interface of the high-temperature-stage economizer 9 are respectively communicated with the fourth interface of the low-temperature-stage economizer 18 and the enthalpy spraying port of the low-temperature-stage compressor 2.

I.e. in operation, the low-temperature stage heat pump components are activated. After the low-temperature stage compressor 2 is electrified, the low-temperature stage compressor 2 compresses low-pressure working medium gas into high-temperature high-pressure liquid, the high-temperature high-pressure working medium flows to the condensing and evaporating heat exchanger 4 through the low-temperature stage four-way valve 3, and a high-temperature high-pressure gasification working medium formed by heat exchange in the condensing and evaporating heat exchanger 4 flows to the low-temperature stage water-fluorine heat exchanger 5. Meanwhile, the water which is forcibly input also passes through the low-temperature-level water-fluorine heat exchanger 5, the hot water heated by the working medium is sent to the energy consumption tail end 1 used by the user, and the working medium is cooled into liquid which flows to the first drying filter 39 and the liquid storage tank 38 in sequence. Since the first check valve 14, the second check valve 15, the third check valve 16, the fourth check valve 17 and the low-temperature-stage throttling valve 37 are closed to communicate with the low-temperature-stage economizer 18, the liquid working medium flows along the first check valve 14, the low-temperature-stage economizer 18, the low-temperature-stage throttling valve 37, the third check valve 16, the second dry filter 40 and flows towards the outdoor finned heat exchanger 6. Meanwhile, part of the liquid working medium flows back to the low-temperature-stage economizer 18 through the third check valve 16, the second check valve 15, the fourth check valve 17 and the first check valve 14 to be throttled and then flows to the outdoor fin heat exchanger 6. The working medium is vaporized by the heat absorption of the outdoor fin heat exchanger 6 and is sucked into the low-temperature stage compressor 2, and the cycle work is repeated. Therefore, under the action of the low-temperature-stage economizer 18, the working medium is effectively depressurized and cooled, and the low-temperature-stage economizer plays a certain role in reducing the exhaust temperature and the exhaust pressure of the low-temperature-stage compressor 2 and reducing the loss of the low-temperature-stage compressor 2.

In the meantime, the middle air injection loop is opened under a certain low temperature environment. The enhanced vapor injection throttle valve 19 and the enhanced vapor injection solenoid valve 8 are respectively closed, so that part of the working medium flowing through the low-temperature-stage economizer 18 flows back to the temperature-replacing-stage economizer and the enhanced vapor injection solenoid valve 8 through the enhanced vapor injection throttle valve 19 and flows to an enthalpy injection port of the low-temperature-stage compressor 2, the exhaust amount of the low-temperature-stage compressor 2 is increased, and the heating capacity is increased.

When the ambient temperature is again lower than the rated temperature, the high-temperature-level heat pump component operates. The high-temperature stage compressor 10 compresses a low-pressure and low-temperature working medium into high-temperature and high-pressure gas, the high-temperature and high-pressure gas flows to the high-temperature stage water-fluorine heat exchanger 12 through the high-temperature stage four-way valve 11, the forcibly input water also passes through the high-temperature stage water-fluorine heat exchanger 12, and the hot water heated by the working medium is sent to the energy consumption tail end 1 for a user to use. And the cooled and liquefied working medium flows to the high-temperature-stage economizer 9 through the third dry filter 22. Under the action of the high-temperature-stage economizer 9, the exhaust temperature and the exhaust pressure of the high-temperature-stage compressor 10 are reduced, and the loss of the high-temperature-stage compressor 10 is reduced.

In addition, under a lower temperature environment, the enhanced vapor injection solenoid valve 8 is opened, so that the working medium from the fourth interface of the low-temperature stage economizer 18 flows through the enhanced vapor pipeline and the high-temperature stage economizer 9 and then returns to the enthalpy injection port of the low-temperature stage compressor 2. And the air displacement of the low-temperature stage compressor 2 in a low-temperature environment is further improved, the heating capacity is increased, the heat exchange efficiency is improved, and the heating performance is ensured.

Referring to fig. 1 to 2, the heat pump system further includes an energy storage buffer water tank 23, a low-temperature-level water pump 24, and a circulating water pump 25, and the energy storage buffer water tank 23 is provided with a liquid supply pipeline 26 and a liquid return pipeline 27. The liquid supply pipeline 26 connects the energy consumption tail end 1, the energy storage buffer water tank 23, the high-temperature-level water-fluorine heat exchanger 12 and the circulating water pump 25 to form an energy storage circulating path, and the liquid return pipeline 27 connects the energy storage buffer water tank 23, the low-temperature-level water-fluorine heat exchanger 5 and the low-temperature-level water pump 24 to form a water return circulating path.

The energy consumption tail end 1 is provided with a water outlet 28 and a water return port 29, and the water outlet 28 and the water return port 29 are respectively communicated with the energy storage buffer water tank 23 and the high-temperature-level water-fluorine heat exchanger 12 through a liquid supply pipeline 26. And, the energy storage buffer water tank 23 is provided with a liquid storage outer cavity 30 and a liquid storage inner cavity 31, the liquid storage inner cavity 31 is located in the middle of the liquid storage outer cavity 30, and the upper part and the lower part of the liquid storage inner cavity 31 are respectively communicated with the liquid storage outer cavity 30. The water outlet 28 of the energy consumption tail end 1 is communicated with the upper part of a liquid storage outer cavity 30 through a liquid supply pipeline 26, the lower part of the liquid storage outer cavity 30 is communicated with the liquid outlet end of the low-temperature-level water pump 24 through a liquid return pipeline 27, the upper part of the liquid storage inner cavity 31 is communicated with the liquid inlet end of the low-temperature-level water-fluorine heat exchanger 5 through the liquid return pipeline 27, and the lower part of the liquid storage inner cavity 31 is communicated with the liquid inlet end of the circulating water pump 25 through the liquid supply pipeline 26.

That is, in operation, the water source at the energy consumption end 1 enters the upper part of the outer liquid storage cavity 30 of the energy storage buffer water tank 23 from the water outlet 28 along the liquid supply pipeline 26 and flows into the upper part of the inner liquid storage cavity 31. The water source at the upper part of the liquid storage inner cavity 31 flows into the low-temperature-level water-fluorine heat exchanger 5 through the liquid return pipeline 27 for heat exchange, the heated hot water flows back to the lower part of the liquid storage outer cavity 30 of the energy storage buffer water tank 23 under the action of the low-temperature-level water pump 24, the hot water at the lower part of the liquid storage outer cavity 30 is pumped into the high-temperature-level water-fluorine heat exchanger 12 for high-temperature heating under the power action of the circulating pump, and the high-temperature hot water flows back to the energy consumption tail end 1.

Therefore, the high-temperature system and the low-temperature system jointly use the energy storage buffer water tank 23 with the structure, the applicability is high, the thermal efficiency is improved, and the use quality of the heat pump system is ensured. Meanwhile, the energy storage buffer water tank 23 effectively separates the return water at the energy consumption tail end 1 from the water passing through the low-temperature system by using the liquid storage inner cavity 31 in the middle, and the heat efficiency is improved. In addition, the energy consumption tail end 1 of the heat pump system is provided with a water outlet 28 and a water return port 29, the refrigeration and heating functions can be covered by utilizing the two interfaces, the applicability is strong, and the assembly is simple.

Referring to fig. 1 to 2, the energy storage buffer water tank 23 is provided with an electric heating pipe 32. The electric heating pipe 32 is connected with a first temperature sensor 33 and a second temperature sensor 34 by signals, the first temperature sensor 33 and the electric heating pipe 32 are respectively installed in the liquid storage outer cavity 30, and the second temperature sensor 34 is installed in a box body of the heat pump system. And a third temperature sensor 35 connected with the low-temperature water pump 24 and the electric heating pipe 32 is installed at a water outlet 28 of the energy consumption tail end 1, and a fourth temperature sensor 36 connected with the circulating water pump 25 and the electric heating pipe 32 is installed at a liquid inlet end of the circulating water pump 25. An anti-freezing temperature controller 41 is installed in the box body of the heat pump system, and the anti-freezing temperature controller 41 is respectively in signal connection with the electric heating pipe 32.

When the defrosting function is started, the low-temperature system only consumes the heat of the hot water stored in the energy storage buffer water tank 23, the circulating water pump 25 is turned off, and when the first temperature sensor 33 detects that the energy storage buffer water tank 23 is too low, the electric heating pipe 32 is turned on for assistance, so that the defrosting effect is achieved, and the use experience of the tail end of a user is not influenced.

The third temperature sensor 35 and the fourth temperature sensor 36 respectively detect the temperature of the water at the energy consumption end 1 and the temperature of the water at the energy storage buffer water tank 23, and effectively control the starting sequence of the low-temperature heat pump component, the high-temperature heat pump component and the intermediate air injection loop according to the practical application, so as to ensure the heating capacity of the heat pump system in the low-temperature environment. In addition, the second temperature sensor 34 and the anti-freezing temperature controller 41 which are arranged in a closed manner in the whole system effectively control the electric heating pipe to be not lower than the freezing point, protect pipelines in the box body of the system from being frozen and damage, and ensure the normal operation of the system.

The above embodiments are only the embodiments with better effect, and any structure identical or equivalent to the single-stage operation cascade type cold and hot water heat pump system of the present invention is within the protection scope of the present invention.