Air source heat pump type cold and hot water unit driven by low-environment-temperature gas-electric hybrid power

Abstract

The invention discloses an air source heat pump type cold and hot water unit driven by low-environment-temperature gas-electric hybrid power, relates to the technical field of air source heat pump air conditioners, and solves the problems that under the low-temperature environment, the heating capacity of an air source heat pump is attenuated, and defrosting energy consumption is high; and an air-conditioning heat pump driven by a gas engine is low in efficiency and poor in economical efficiency during low-load refrigeration. The system comprises a gas engine, the gas engine is in control connection with a refrigerant system through a transmission device, a heat recovery loop and a heat dissipation loop are arranged on the gas engine, and the refrigerant system comprises an open-type compressor and an electric compressor which are connected in parallel. Exhaust ports of the open-type compressor and the electric compressor are respectively connected with an exhaust confluence tee joint through one-way valves, another interface of the exhaust confluence tee joint is connected to an inlet of the oil separator through a pipeline, and air suction ports of the open-type compressor and the electric compressor are respectively connected with an air suction shunting tee joint through a pipeline I and a pipeline II.

Description

Technical Field

[0001] The invention relates to the technical field of air source heat pump air conditioners, and in particular to an air source heat pump type hot and cold water unit driven by a low ambient temperature gas-electric hybrid power. Background Art

[0002] In recent years, electric air source heat pump units have been widely developed and have played an important role in the cooling and heating systems of buildings. However, in areas north of the Yangtze River, winter heating often faces problems of low temperature capacity attenuation and frost, which leads to a significant increase in energy consumption. In contrast, gas engine-driven air conditioning heat pump units can effectively improve heating capacity in low temperature environments because they can recover heat from the engine cylinder liner and flue gas, and do not require defrosting. Therefore, they have obvious advantages in heating performance over electric-driven air source heat pumps.

[0003] However, the efficiency of air conditioning heat pump units driven by gas engines is low when cooling low loads, especially when gas prices are high and low loads account for a large proportion. Its operating cost-effectiveness is not as good as that of electric air source heat pumps, especially electric drive variable frequency air source heat pumps. Therefore, the development of a heat pump system that can maintain high efficiency and economy under different load and environmental conditions has become a key issue that needs to be solved in technological development. Summary of the invention

[0004] In order to solve the above problems, that is, to solve the problems raised by the above background technology, the present invention proposes a low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit, which includes a gas engine, and the gas engine is connected to a refrigerant system through a transmission device. The gas engine is provided with a heat recovery circuit and a heat dissipation circuit. The refrigerant system includes: an open compressor and an electric compressor are connected in parallel, and the exhaust ports of the open compressor and the electric compressor are respectively connected to an exhaust merging tee through a one-way valve, and the other interface of the exhaust merging tee is connected to the inlet of an oil separator through a pipeline. The open compressor and the electric compressor are connected in parallel. The air intake of the machine is connected to an air intake diversion tee through pipeline one and pipeline two, respectively, and the other interface of the air intake diversion tee is connected to the outlet of the gas-liquid separator through a pipeline; two branches are also arranged at the bottom of the oil separator, and solenoid valves and capillaries are arranged on the two branches in sequence, and the other ends of the two branches are connected to pipeline one and pipeline two, respectively; the first port of the refrigerant-water heat exchanger is connected to the first port of the air heat exchanger through pipeline three, the second port of the refrigerant-water heat exchanger is connected to the E port of the four-way reversing valve through a pipeline, and the C port of the four-way reversing valve is connected to the second port of the air heat exchanger through a pipeline.

[0005] The present invention is further configured as follows: the D port of the four-way reversing valve is connected to the outlet of the oil separator through a pipeline, and the S port of the four-way reversing valve is connected to the inlet of the gas-liquid separator through a pipeline.

[0006] The present invention is further configured as follows: a main expansion valve is provided on pipeline three, and a third branch is also provided on pipeline three close to the refrigerant-water heat exchanger side of the main expansion valve, and the third branch is connected to the refrigerant side inlet of the heat recovery heat exchanger through an auxiliary expansion valve, and the refrigerant side outlet of the heat recovery heat exchanger is connected to pipeline four through a pipeline.

[0007] The present invention is further configured as follows: the heat recovery circuit includes a radiator, a flue gas heat exchanger and a cooling water pump, the outlet of the radiator is connected to the inlet of the cooling water pump through a pipeline five, the outlet of the cooling water pump is connected to the water side inlet of the flue gas heat exchanger through a pipeline, the water side outlet of the flue gas heat exchanger is connected to the cooling water inlet of the gas engine through a pipeline, and the cooling water outlet of the gas engine is connected to the first interface of the diversion type three-way valve through a pipeline.

[0008] The present invention is further configured as follows: the heat dissipation circuit includes a radiator, a heat recovery heat exchanger and a diverter type three-way valve, the second interface of the diverter type three-way valve is connected to the water side inlet of the heat recovery heat exchanger through a pipeline, the water side outlet of the heat recovery heat exchanger is connected to pipeline five through a pipeline, and the third interface of the diverter type three-way valve is connected to the inlet of the radiator through a pipeline.

[0009] The present invention is further configured as follows: the gas engine is connected to a smoke exhaust port via a smoke heat exchanger.

[0010] The present invention is further configured as follows: the rated refrigeration capacity of the electric compressor is in the range of 20% to 50% of the rated refrigeration capacity of the open compressor.

[0011] The beneficial technical effects of the present invention are as follows: the present invention can select the most suitable driving mode under different ambient temperatures and load conditions through gas-electric hybrid drive, thereby improving the overall energy efficiency. When the cooling load is low, energy consumption can be reduced by stopping the gas engine and only using the electric compressor to operate. When heating, especially when the ambient temperature is below 5°C, by recovering the exhaust heat of the gas engine, the attenuation of the heating capacity is significantly alleviated to ensure the heating effect, while reducing pollution to the environment. In addition, the heating capacity is increased by the heat recovery circuit, and defrosting is not required, which improves the heating efficiency. The system can automatically adjust the working mode according to the actual load and ambient temperature, and has good flexibility and adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Shown is a schematic diagram of the structure of the present invention.

[0013] Figure 2 The first unit efficiency diagram of the present invention is shown.

[0014] Figure 3 The second unit efficiency diagram of the present invention is shown.

[0015] Figure 4 The refrigeration efficiency curve of the present invention is shown.

[0016] Figure 5 A curve diagram showing the heating capacity VS ambient temperature change of the present invention is shown.

[0017] Figure numerals: 1. open compressor, 2. electric compressor, 3. oil separator, 4. gas-liquid separator, 5. refrigerant-water heat exchanger, 6. air heat exchanger, 7. radiator, 8. heat recovery heat exchanger, 9. flue gas heat exchanger, 10. cooling water pump, 11. gas engine, 12. transmission device, 13. capillary tube, 14. exhaust converging tee, 15. suction diverting tee, 16. four-way reversing valve, 17. main expansion valve, 18. auxiliary expansion valve, 19. diverting three-way valve. DETAILED DESCRIPTION

[0018] Please refer to the attached Figure 1-5 Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0019] The present invention proposes a low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit, comprising a gas engine 11, the gas engine 11 is connected to a refrigerant system through a transmission device 12, an open compressor 1 is driven by the gas engine 11, and an electric compressor 2 is driven by electricity, and the two are arranged in parallel in the refrigerant system. Among them, the rated refrigeration capacity of the electric compressor 2 is selected within the range of 20% to 50% of the rated refrigeration capacity of the open compressor 1; the one-way valve can be replaced by a non-return mechanism at the internal exhaust port of the open compressor 1 and the electric compressor 2.

[0020] The refrigerant system includes: an open compressor 1 and an electric compressor 2 are connected in parallel, and the exhaust ports of the open compressor 1 and the electric compressor 2 are respectively connected to an exhaust merging tee 14 through a one-way valve, and the one-way valve ensures that the refrigerant vapor can only flow in one direction to prevent backflow. The other interface of the exhaust merging tee 14 is connected to the inlet of the oil separator 3 through a pipeline, and the air intake ports of the open compressor 1 and the electric compressor 2 are respectively connected to an air intake diversion tee 15 through pipeline one and pipeline two, and the air intake diversion tee 15 diverts the refrigerant liquid into their respective compressors. The other interface of the air intake diversion tee 15 is connected to the outlet of the gas-liquid separator 4 through a pipeline; the gas-liquid separator 4 is used to separate the gas and liquid in the refrigerant to improve the system efficiency.

[0021] Two branches are also provided at the bottom of the oil separator 3, and the two branches are provided with a solenoid valve and a capillary tube 13 in sequence, and the solenoid valve and the capillary tube 13 can control the oil return amount of the compressor. The other ends of the two branches are connected to pipeline 1 and pipeline 2 respectively, and the D port of the four-way reversing valve 16 is connected to the outlet of the oil separator 3 through the pipeline, and the S port of the four-way reversing valve 16 is connected to the inlet of the gas-liquid separator 4 through the pipeline 4.

[0022] A main expansion valve 17 is provided on pipeline three, and the main expansion valve 17 controls the flow rate of the refrigerant flowing into the refrigerant-water heat exchanger 5, and adjusts the refrigerant flow rate according to the system load demand. The main expansion valve 17 is also provided with a third branch on pipeline three near the side of the refrigerant-water heat exchanger 5. The third branch is connected to the refrigerant side inlet of the heat recovery heat exchanger 8 through the auxiliary expansion valve 18, and the auxiliary expansion valve 18 controls the flow rate of the refrigerant flowing into the heat recovery heat exchanger 8. The refrigerant side outlet of the heat recovery heat exchanger 8 is connected to pipeline four through a pipeline. The heat recovery heat exchanger 8 serves as a second evaporator to recover engine exhaust heat, thereby improving the heating capacity and energy efficiency at low ambient temperatures.

[0023] The refrigerant-water heat exchanger 5 is internally installed with an air conditioning water circulation pipeline, and the refrigerant-water heat exchanger 5 is used to perform heat exchange between the refrigerant and the air conditioning water to achieve cooling or heating. The first port of the refrigerant-water heat exchanger 5 is connected to the first port of the air heat exchanger 6 through the pipeline 3, the second port of the refrigerant-water heat exchanger 5 is connected to the E port of the four-way reversing valve 16 through the pipeline, and the C port of the four-way reversing valve 16 is connected to the second port of the air heat exchanger 6 through the pipeline. When cooling, the first port of the refrigerant-water heat exchanger 5 is equivalent to the inlet, the second port of the refrigerant-water heat exchanger 5 is equivalent to the outlet, the first port of the air heat exchanger 6 is equivalent to the outlet, and the second port of the air heat exchanger 6 is equivalent to the inlet; when heating, it is the opposite of cooling. At this time, the first port of the refrigerant-water heat exchanger 5 is equivalent to the outlet, the second port of the refrigerant-water heat exchanger 5 is equivalent to the inlet, the first port of the air heat exchanger 6 is equivalent to the inlet, and the second port of the air heat exchanger 6 is equivalent to the outlet.

[0024] The gas engine 11 is provided with a heat recovery circuit and a heat dissipation circuit, which constitute a power system. The heat recovery circuit includes a radiator 7, a flue gas heat exchanger 9 and a cooling water pump 10. The radiator 7 is used to dissipate heat and discharge the excess heat in the system to the outside. The flue gas heat exchanger 9 recovers the flue gas heat discharged by the gas engine 11 to increase the heating capacity of the system. The cooling water pump 10 circulates cooling water for heat recovery and heat dissipation. The outlet of the radiator 7 is connected to the inlet of the cooling water pump 10 through a pipeline 5, and the outlet of the cooling water pump 10 is connected to the water side inlet of the flue gas heat exchanger 9 through a pipeline. The water side outlet of the flue gas heat exchanger 9 is connected to the cooling water inlet of the gas engine 11 through a pipeline, and the cooling water outlet of the gas engine 11 is connected to the first interface of the diverter type three-way valve 19 through a pipeline. The diverter type three-way valve 19 controls the flow direction of the cooling water and directs the cooling water to the heat recovery heat exchanger or the radiator as needed.

[0025] The heat dissipation circuit includes a radiator 7, a heat recovery heat exchanger 8 and a diverter type three-way valve 19, the second interface of the diverter type three-way valve 19 is connected to the water side inlet of the heat recovery heat exchanger 8 through a pipeline, the water side outlet of the heat recovery heat exchanger 8 is connected to the pipeline 5 through a pipeline, and the third interface of the diverter type three-way valve 19 is connected to the inlet of the radiator 7 through a pipeline. It is used to control the cooling water to release heat to the heat recovery heat exchanger 8 or the radiator 7.

[0026] The gas engine 11 is connected to a smoke exhaust port through a smoke heat exchanger 9. The gas engine 11 provides power to drive the open compressor 1 and generate recoverable heat. The smoke exhaust port discharges smoke generated by the combustion of the gas engine 11.

[0027] The working mode during cooling is: when the cooling load is low, the gas engine 11 stops, and only the electric compressor 2 is started to run alone, and the high efficiency of the electric compressor 2 is used to replace the low efficiency of the gas engine 11 at low load, thereby improving the overall energy efficiency. In the intermediate load range, you can choose to operate with gas-electric hybrid power, or you can rely solely on the gas engine 11 to drive the open compressor 1 to adapt to different load requirements. In the high load range, gas-electric hybrid power operation is adopted to ensure that the system maintains efficient operation while meeting the high load requirements of cooling.

[0028] Specifically, the refrigerant system circulation principle during refrigeration is: the open compressor 1 or the electric compressor 2 discharges a mixed gas of refrigerant and refrigeration oil, which enters the oil separator 3 through a one-way valve. The purpose of setting the one-way valve is to prevent the exhaust gas of the compressor in the working state from flowing back to the compressor in the stopped state. The refrigeration oil is separated inside the oil separator 3, and returns to the pipeline 1 and pipeline 2 at the air intake of the open compressor 1 and the electric compressor 2 through the first branch and the second branch of the two throttling capillaries 13 set at the bottom of the oil separator 3 respectively. The returned refrigeration oil returns to the working compressor together with the inhaled refrigerant to ensure the lubrication of the compressor. In addition, after the refrigeration oil is separated by the oil separator 3, the relatively pure refrigerant gas enters through the D port of the four-way universal reversing valve 16, is discharged from the C port of the four-way universal reversing valve 16, and then enters the air heat exchanger 6 to be condensed into liquid by the air. The condensed liquid enters the refrigerant-water heat exchanger 5 through the pipeline 3, and the main expansion valve 17 on the pipeline 3 controls the refrigerant flow to match the air conditioning water load. The liquid refrigerant absorbs the heat of the air-conditioning water in the refrigerant-water heat exchanger 5 and vaporizes. It enters the E port of the four-way reversing valve 16 through the pipeline and flows out from the S port to enter the pipeline 4. After entering the gas-liquid separator 4 through the pipeline 4, the refrigerant vapor enters the suction flow tee 15, and then enters the corresponding compressor through the pipeline 1 or pipeline 2 for compression again. The auxiliary expansion valve 18 in the third branch is closed during refrigeration.

[0029] The circulation principle of the engine cooling water during cooling is: the cooling water, driven by the cooling water pump 10, passes through the gas engine 11 and the flue gas heat exchanger 9 in sequence, absorbs the heat in the cylinder of the gas engine 11 and the flue gas, and then flows to the radiator 7 through the diversion three-way valve 19 to dissipate heat. After the cooling water temperature is reduced, it enters the cooling water pump 10 again.

[0030] The working mode during heating is: when the ambient temperature is high and the heating demand is low, only the electric compressor 2 is started to run alone to meet the lower heat load with high efficiency. On the contrary, when the ambient temperature drops below 5°C, the open compressor 1 driven by the gas engine 11 is switched to run alone. At this time, the diverter-type three-way valve 19 adjusts the flow direction of the cooling water so that it enters the heat recovery heat exchanger 8 to release heat, and the auxiliary expansion valve 18 is opened accordingly, so that the refrigerant flows into the heat recovery heat exchanger 8 and uses it as an auxiliary evaporator.

[0031] Specifically, the refrigerant circulation principle during heating is: the open compressor 1 or the electric compressor 2 discharges a mixed gas of refrigerant and refrigeration oil, which enters the oil separator 3 through a one-way valve. The purpose of setting the one-way valve is to prevent the exhaust gas of the compressor in the working state from flowing back to the compressor in the stopped state. The refrigeration oil is separated inside the oil separator 3, and returns to the pipeline 1 and pipeline 2 at the air intake of the open compressor 1 and the electric compressor 2 respectively through the branches of the two throttling capillaries 13 set at the bottom of the oil separator 3. The returned refrigeration oil returns to the working compressor together with the inhaled refrigerant to ensure the lubrication of the compressor. In addition, after the refrigeration oil is separated by the oil separator 3, the relatively pure refrigerant gas enters through the D port of the four-way universal reversing valve 16, is discharged from the E port of the four-way universal reversing valve 16, and then enters the refrigerant-water heat exchanger 5. The gaseous refrigerant releases heat to the air conditioning water and then liquefies and condenses. The condensed refrigerant liquid enters the air heat exchanger 6 through the pipeline 3, and the main expansion valve 17 on the pipeline 3 controls the refrigerant flow to match the load of the air heat exchanger 6. The liquid refrigerant absorbs the heat of the ambient air in the air heat exchanger 6, vaporizes, and enters the C port of the four-way reversing valve 16 through the pipeline, and then flows out from the S port into the pipeline four. After entering the gas-liquid separator 4 through the pipeline four, the refrigerant vapor enters the suction diversion tee 15, and then enters the corresponding compressor through the pipeline one or pipeline two for compression again. At the same time, the liquid refrigerant enters the third branch from the pipeline three, and the auxiliary expansion valve 18 controls the refrigerant flow rate flowing into the heat recovery heat exchanger 8 to match the heat of the cooling water. The liquid refrigerant that absorbs heat in the heat recovery heat exchanger 8 vaporizes and enters the pipeline four.

[0032] The circulation principle of the engine cooling water during heating is that the cooling water, driven by the cooling water pump 10, passes through the gas engine 11 and the flue gas heat exchanger 9 in sequence, absorbs the heat in the cylinder of the gas engine 11 and the flue gas, and then flows to the heat recovery heat exchanger 8 through the diversion three-way valve 19 to release heat to the refrigerant. After the cooling water temperature is reduced, it enters the cooling water pump 10 again.

[0033]

[0034] GHP stands for single gas engine driven compressor; EHP stands for Electric Single Drive Compressor; GHP+EHP stands for gas-electric hybrid drive compressor.

[0035]

[0036] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0037] In the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0038] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] The term "comprise" or any other similar term is intended to cover a non-exclusive inclusion, such that a process, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, article, or apparatus / device.

[0040] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit, comprising a gas engine (11), wherein the gas engine (11) is connected to a refrigerant system through a transmission device (12), characterized in that: The gas engine (11) is provided with a heat recovery circuit and a heat dissipation circuit, and the refrigerant system comprises: The open compressor (1) and the electric compressor (2) are connected in parallel, the exhaust ports of the open compressor (1) and the electric compressor (2) are respectively connected to an exhaust merging tee (14) via a one-way valve, the other interface of the exhaust merging tee (14) is connected to the inlet of an oil separator (3) via a pipeline, the air intake ports of the open compressor (1) and the electric compressor (2) are respectively connected to an air intake splitting tee (15) via a first pipeline and a second pipeline, the other interface of the air intake splitting tee (15) is connected to the outlet of a gas-liquid separator (4) via a pipeline; Two branches are also provided at the bottom of the oil separator (3), and solenoid valves and capillaries (13) are provided on the two branches in sequence, and the other ends of the two branches are connected to pipeline one and pipeline two respectively; The first port of the refrigerant-water heat exchanger (5) is connected to the first port of the air heat exchanger (6) via a pipeline, the second port of the refrigerant-water heat exchanger (5) is connected to the E port of the four-way reversing valve (16) via a pipeline, and the C port of the four-way reversing valve (16) is connected to the second port of the air heat exchanger (6) via a pipeline.

2. According to claim 1, a low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit, characterized in that: The D port of the four-way reversing valve (16) is connected to the outlet of the oil separator (3) through a pipeline, and the S port of the four-way reversing valve (16) is connected to the inlet of the gas-liquid separator (4) through a pipeline.

3. According to claim 1, a low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit, characterized in that: A main expansion valve (17) is provided on the pipeline three, and a third branch is also provided on the pipeline three near the refrigerant-water heat exchanger (5). The third branch is connected to the refrigerant side inlet of the heat recovery heat exchanger (8) through an auxiliary expansion valve (18), and the refrigerant side outlet of the heat recovery heat exchanger (8) is connected to the pipeline four through a pipeline.

4. The low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit according to claim 1, characterized in that: The heat recovery circuit comprises a radiator (7), a flue gas heat exchanger (9) and a cooling water pump (10); the outlet of the radiator (7) is connected to the inlet of the cooling water pump (10) via a pipeline; the outlet of the cooling water pump (10) is connected to the water side inlet of the flue gas heat exchanger (9) via a pipeline; the water side outlet of the flue gas heat exchanger (9) is connected to the cooling water inlet of the gas engine (11) via a pipeline; and the cooling water outlet of the gas engine (11) is connected to the first interface of the diversion type three-way valve (19) via a pipeline.

5. The low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit according to claim 1, characterized in that: The heat dissipation circuit comprises a radiator (7), a heat recovery heat exchanger (8) and a diverter-type three-way valve (19); a second interface of the diverter-type three-way valve (19) is connected to a water-side inlet of the heat recovery heat exchanger (8) via a pipeline; a water-side outlet of the heat recovery heat exchanger (8) is connected to pipeline five via a pipeline; and a third interface of the diverter-type three-way valve (19) is connected to an inlet of the radiator (7) via a pipeline.

6. The low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit according to claim 1, characterized in that: The gas engine (11) is connected to a smoke exhaust port via a smoke heat exchanger (9).

7. The low ambient temperature gas-electric hybrid driven air source heat pump type hot and cold water unit according to claim 1, characterized in that: The rated refrigeration capacity of the electric compressor (2) is in the range of 20% to 50% of the rated refrigeration capacity of the open compressor (1).

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