Carbon dioxide air conditioning heat pump system for compact electric vehicles

Abstract

A compact carbon dioxide air conditioning heat pump system for electric vehicles in the field of automobile air conditioning technology includes an outdoor heat exchanger, a water pump, a water tank, a three-way valve, a shell and tube heat exchanger, a warm air core, a throttle valve, a compressor, a battery cold plate, a cold air core, a water circulation pipeline, a carbon dioxide working medium circulation pipeline, and a bypass pipeline. The first shell and tube heat exchanger includes a main pipe and two branch pipes, and the second shell and tube heat exchanger includes a main pipe and three branch pipes. After the various components of the present invention are connected in series through different circulation pipelines, four water circulation loops and a carbon dioxide working medium circulation loop are respectively formed, which can respectively realize the cooling mode, heating mode, dehumidification mode and fast charging mode, meeting the needs of electric vehicles.

Description

Technical Field

[0001] The present invention relates to a heat pump system in the technical field of automobile air conditioning, in particular to a compact carbon dioxide air conditioning heat pump system for electric vehicles in which a carbon dioxide working medium circulation pipeline is connected to various series components by welding. Background Art

[0002] Due to the limited space of small electric vehicles, it is difficult to arrange the internal air conditioning part, which needs to be simplified, and even some functions need to be sacrificed to meet the space requirements. Electric vehicles do not have an internal combustion engine to provide waste heat for heating, so they need a heat pump system to provide warm air in winter. The heat pump can absorb heat from the ambient air, transfer the heat to the circulating water through the working fluid circulation, and play a role in heating. Traditional heat pumps mostly use traditional working fluids such as R134a and R410a, which are less environmentally friendly and face the trend of gradual elimination.

[0003] However, in the prior art, general automobile air conditioners use pressure plate type air conditioning pipe interfaces, which are convenient for installation and disassembly, but have poor sealing performance and can only be used for low-pressure working fluids. The working pressure of CO2 is relatively high, and the general pressure plate type interface has poor sealing performance. Summary of the invention

[0004] In view of the deficiencies of the above-mentioned prior art, the present invention provides a compact carbon dioxide air-conditioning heat pump system for electric vehicles, which adopts two shell-and-tube heat exchangers to enable more flexible spatial layout; by controlling two three-way valves, a throttle valve, a compressor and four water pumps, stable and efficient operation of the air-conditioning cooling, heating and defrosting working modes is guaranteed.

[0005] The present invention is realized by the following technical scheme, which includes an outdoor heat exchanger, a first water pump, a second water tank, a second water pump, a first water tank, a first three-way valve, a second three-way valve, a first sleeve heat exchanger, a warm air core, a throttle valve, a compressor, a second sleeve heat exchanger, a third water pump, a third water tank, a fourth water pump, a fourth water tank, a battery cold plate, a cold air core, a first water circulation pipeline, a second water circulation pipeline, a third water circulation pipeline, a fourth water circulation pipeline, a carbon dioxide working medium circulation pipeline, and a bypass pipeline; the first sleeve heat exchanger The heat exchanger is composed of a first shell and tube heat exchanger main pipe, a first branch pipe of the first shell and tube heat exchanger, and a second branch pipe of the first shell and tube heat exchanger. The first branch pipe of the first shell and tube heat exchanger and the second branch pipe of the first shell and tube heat exchanger are both mounted in the first shell and tube heat exchanger main pipe; the second shell and tube heat exchanger is composed of a second shell and tube heat exchanger main pipe, a first branch pipe of the second shell and tube heat exchanger, a second branch pipe of the second shell and tube heat exchanger, and a third branch pipe of the second shell and tube heat exchanger. The first branch pipe of the second shell and tube heat exchanger, the second branch pipe of the second shell and tube heat exchanger, and the third branch pipe of the second shell and tube heat exchanger are both mounted in The second main pipe of the double-tube heat exchanger; the first water tank, the first water pump, the outdoor heat exchanger, the second three-way valve, the main pipe of the first double-tube heat exchanger, and the first three-way valve are sequentially connected in series through the first water circulation pipeline, wherein the two ports of the first three-way valve and the second three-way valve are serially connected in the first water circulation pipeline; the second water tank, the second water pump, the heater core, and the first branch pipe of the first double-tube heat exchanger are sequentially connected in series through the second water circulation pipeline; the throttle valve, the first branch pipe of the second double-tube heat exchanger, the compressor, the second branch pipe of the first double-tube heat exchanger They are connected in series in sequence through a carbon dioxide working medium circulation pipeline; the third water tank, the third water pump, the second branch pipe of the second shell and tube heat exchanger, and the battery cold plate are connected in series in sequence through a third water circulation pipeline; the fourth water pump, the fourth water tank, the cold air core, and the third branch pipe of the second shell and tube heat exchanger are connected in series in sequence through a fourth water circulation pipeline; one port of the bypass pipeline is connected to the third port of the first three-way valve, the other port of the bypass pipeline is connected to the third port of the second three-way valve, and the second shell and tube heat exchanger main pipe is connected in series in the bypass pipeline.

[0006] Further, in the present invention, the exhaust pressure of the compressor is 115 bar to 123 bar.

[0007] Furthermore, in the present invention, the carbon dioxide working medium circulation pipeline is connected to each series component by welding.

[0008] Compared with the prior art, the present invention has the following beneficial effects: first, it can realize cooling mode, heating mode, dehumidification mode and fast charging mode, meeting the needs of electric vehicles; second, the whole system adopts two shell-and-tube heat exchangers, which can be flexibly arranged in space and is more suitable for small electric vehicles; third, the CO2 pipeline is connected by welding, avoiding the problem of interface fluid leakage; fourth, the system adopts CO2 working fluid, which is natural and environmentally friendly and has good heating performance at low temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0010] Figure 2 This is a schematic diagram of the port arrangement of the first shell and tube heat exchanger in an embodiment of the present invention;

[0011] Figure 3 It is a schematic diagram of the port arrangement of the second shell and tube heat exchanger in an embodiment of the present invention;

[0012] Among them: 1. outdoor heat exchanger, 2. first water pump, 3. second water tank, 4. second water pump, 5. first water tank, 6. first three-way valve, 7. second three-way valve, 8. first shell and tube heat exchanger, 9. warm air core, 10. throttle valve, 11. compressor, 12. second shell and tube heat exchanger, 13. third water pump, 14. third water tank, 15. fourth water tank, 16. fourth water pump, 17. battery cold plate, 18. cold air core, 19. first water circulation pipeline, 20. The second water circulation pipeline, 21. The third water circulation pipeline, 22. The fourth water circulation pipeline, 23. The carbon dioxide working medium circulation pipeline, 24. The bypass pipeline, 25. The main pipe of the first shell and tube heat exchanger, 26. The first branch pipe of the first shell and tube heat exchanger, 27. The second branch pipe of the first shell and tube heat exchanger, 28. The main pipe of the second shell and tube heat exchanger, 29. The first branch pipe of the second shell and tube heat exchanger, 30. The second branch pipe of the second shell and tube heat exchanger, 31. The third branch pipe of the second shell and tube heat exchanger. DETAILED DESCRIPTION

[0013] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is based on the technical solution of the present invention and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiment.

[0014] Example

[0015] Implementation example Figures 1 to 3 As shown, the present invention includes an outdoor heat exchanger 1, a first water pump 2, a second water tank 3, a second water pump 4, a first water tank 5, a first three-way valve 6, a second three-way valve 7, a first shell and tube heat exchanger 8, a warm air core 9, a throttle valve 10, a compressor 11, a second shell and tube heat exchanger 12, a third water pump 13, a third water tank 14, a fourth water tank 15, a fourth water pump 16, a battery cold plate 17, a cold air core 18, a first water circulation pipeline 19, a second water circulation pipeline 20, a third water circulation pipeline 21, a fourth water circulation pipeline 22, a carbon dioxide working medium circulation pipeline 23, and a bypass pipeline 24;

[0016] The first shell and tube heat exchanger 8 is composed of a first shell and tube heat exchanger main pipe 25, a first shell and tube heat exchanger first branch pipe 26, and a first shell and tube heat exchanger second branch pipe 27. The first shell and tube heat exchanger first branch pipe 26 and the first shell and tube heat exchanger second branch pipe 27 are both sleeved in the first shell and tube heat exchanger main pipe 25. The second shell and tube heat exchanger 12 is composed of a second shell and tube heat exchanger main pipe 28, a second shell and tube heat exchanger first branch pipe 29, a second shell and tube heat exchanger second branch pipe 30, and a second shell and tube heat exchanger third branch pipe 31. The second shell and tube heat exchanger first branch pipe 29, the second shell and tube heat exchanger second branch pipe 30, and the second shell and tube heat exchanger third branch pipe 31 are all sleeved in the second shell and tube heat exchanger main pipe 28.

[0017] The two ports of the first casing heat exchanger main pipe 25 are b and e, the two ports of the first branch pipe 26 of the first casing heat exchanger are a and d, the two ports of the second branch pipe 27 of the first casing heat exchanger are c and f, the two ports of the second casing heat exchanger main pipe 28 are h and L, the two ports of the first branch pipe 29 of the second casing heat exchanger are g and k, the two ports of the second branch pipe 30 of the second casing heat exchanger are i and m, and the two ports of the third branch pipe 31 of the second casing heat exchanger are j and n; the three ports of the first three-way valve 6 are o, p and q, and the three ports of the second three-way valve 7 are r, s and t;

[0018] The first water tank 5, the first water pump 2, the outdoor heat exchanger 1, the second three-way valve 7, the first shell and tube heat exchanger main pipe 25, and the first three-way valve 6 are sequentially connected in series through the first water circulation pipeline 19, wherein the first port o and the second port p of the first three-way valve 6 are respectively connected to the first water circulation pipeline 19, the first port r and the second port s of the second three-way valve 7 are respectively connected to the first water circulation pipeline 19, and the two ports b and e of the first shell and tube heat exchanger main pipe 25 are respectively connected to the first water circulation pipeline 19;

[0019] The second water tank 3, the second water pump 4, the heater core 9, and the first branch pipe 26 of the first double-tube heat exchanger are sequentially connected in series through the second water circulation pipeline 20, wherein two ports a and d of the first branch pipe 26 of the first double-tube heat exchanger are respectively connected to the second water circulation pipeline 20;

[0020] The throttle valve 10, the first branch pipe 29 of the second shell-and-tube heat exchanger, the compressor 11, and the second branch pipe 27 of the first shell-and-tube heat exchanger are sequentially connected in series through the carbon dioxide working medium circulation pipeline 23, wherein the two ports c and f of the second branch pipe 27 of the first shell-and-tube heat exchanger are respectively connected to the carbon dioxide working medium circulation pipeline 23, and the two ports g and k of the first branch pipe 29 of the second shell-and-tube heat exchanger are respectively connected to the carbon dioxide working medium circulation pipeline 23;

[0021] The third water tank 14, the third water pump 13, the second branch pipe 30 of the second double-tube heat exchanger, and the battery cold plate 17 are sequentially connected in series through the third water circulation pipeline 21, wherein the two ports i and m of the second branch pipe 30 of the second double-tube heat exchanger are respectively connected to the third water circulation pipeline 21;

[0022] The fourth water tank 15, the fourth water pump 16, the cold air core 18, and the third branch pipe 31 of the second double-tube heat exchanger are sequentially connected in series through the fourth water circulation pipeline 22, wherein two ports j and n of the third branch pipe 31 of the second double-tube heat exchanger are respectively connected to the fourth water circulation pipeline 22;

[0023] One port of the bypass pipeline 24 is connected to the third port q of the first three-way valve 6, and the other port of the bypass pipeline 24 is connected to the third port t of the second three-way valve 7. The second shell and tube heat exchanger main pipe 28 is connected in series in the bypass pipeline 24, and the two ports h and L of the second shell and tube heat exchanger main pipe 28 are respectively connected to the bypass pipeline 24.

[0024] During the implementation of the present invention, after being compressed by the compressor 11, the carbon dioxide enters the f port of the second branch pipe 27 of the first shell and tube heat exchanger, and after releasing heat, flows out from the c port of the second branch pipe 27 of the first shell and tube heat exchanger, then enters the throttle valve 10, flows out from the throttle valve 10, enters the g port of the first branch pipe 29 of the second shell and tube heat exchanger, flows out from the k port of the first branch pipe 29 of the second shell and tube heat exchanger, and then returns to the compressor 11.

[0025] The implementation processes of the cooling mode, heating mode, dehumidification mode and fast charging mode of the present invention are respectively as follows:

[0026] Refrigeration mode: the first three-way valve 6 is connected to the o and p ports, the second three-way valve 7 is connected to the r and s ports, the second water pump 4 is not working, and the first water pump 2, the third water pump 13 and the fourth water pump 16 are working; the speed of the compressor 11 and the flow rate of the fourth water pump 16 are controlled to ensure that the air outlet temperature of the cold air core 18 is 5°C to provide cold air in the car.

[0027] Heating mode: the first three-way valve 6 is connected to the o and q ports, the second three-way valve 7 is connected to the r and t ports, the fourth water pump 16 and the third water pump 13 are not working, and the first water pump 2 and the second water pump 4 are working; the speed of the compressor 11 and the flow rate of the second water pump 4 are controlled to ensure that the air outlet temperature of the heater core 9 is 55°C to provide warm air in the vehicle compartment.

[0028] Dehumidification mode: the first three-way valve 6 connects the o and p ports, and the second three-way valve 7 connects the r and s ports. The third water pump 13 does not work, and the first water pump 2, the second water pump 4, and the fourth water pump 16 work; the speed of the compressor 11 and the flow rate of the fourth water pump 16 are controlled to ensure that the outlet temperature of the cold air core 18 is 5°C. After the outdoor air passes through the cold air core 18, the humidity of the air decreases. The flow rate of the second water pump 4 is controlled to ensure that the temperature of the air rises to the outdoor air temperature after passing through the warm air core 9.

[0029] Fast charging mode: the first three-way valve 6 connects the o and p ports, the second three-way valve 7 connects the r and s ports, the second water pump 4 and the fourth water pump 16 do not work, and the first water pump 2 and the third water pump 13 work; control the speed of the compressor 11 and the flow rate of the third water pump 13 to ensure that the outlet temperature of the battery cold plate 17 is 25°C.

[0030] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A carbon dioxide air conditioning heat pump system for compact electric vehicles, characterized in that , comprising an outdoor heat exchanger (1), a first water pump (2), a second water tank (3), a second water pump (4), a first water tank (5), a first three-way valve (6), a second three-way valve (7), a first shell and tube heat exchanger (8), a warm air core (9), a throttle valve (10), a compressor (11), a second shell and tube heat exchanger (12), a third water pump (13), a third water tank (14), a fourth water tank (15), a fourth water pump (16), a battery cold plate (17), a cold air core (18), a first water circulation pipeline (19), a second water circulation pipeline (20), a third water circulation pipeline (21), a fourth water circulation pipeline (22), a carbon dioxide working medium circulation pipeline (23), and a bypass pipeline (24); The first shell and tube heat exchanger (8) is composed of a first shell and tube heat exchanger main pipe (25), a first shell and tube heat exchanger first branch pipe (26), and a first shell and tube heat exchanger second branch pipe (27), and the first shell and tube heat exchanger first branch pipe (26) and the first shell and tube heat exchanger second branch pipe (27) are both sleeved in the first shell and tube heat exchanger main pipe (25); The second shell and tube heat exchanger (12) is composed of a second shell and tube heat exchanger main pipe (28), a second shell and tube heat exchanger first branch pipe (29), a second shell and tube heat exchanger second branch pipe (30), and a second shell and tube heat exchanger third branch pipe (31), wherein the second shell and tube heat exchanger first branch pipe (29), the second shell and tube heat exchanger second branch pipe (30), and the second shell and tube heat exchanger third branch pipe (31) are all mounted on the second shell and tube heat exchanger. In the heat exchanger main pipe (28); the first water tank (5), the first water pump (2), the outdoor heat exchanger (1), the second three-way valve (7), the first tube heat exchanger main pipe (25), and the first three-way valve (6) are sequentially connected in series through a first water circulation pipeline (19), wherein the two ports of the first three-way valve (6) and the second three-way valve (7) are respectively connected in series in the first water circulation pipeline (19); the second water tank (3), the second water pump (4), the heater core (9), and the first branch pipe (26) of the first tube heat exchanger are sequentially connected in series through a second water circulation pipeline (20); The throttle valve (10), the first branch pipe (29) of the second double-tube heat exchanger, the compressor (11), and the second branch pipe (27) of the first double-tube heat exchanger are sequentially connected in series through a carbon dioxide working medium circulation pipeline (23); The third water tank (14), the third water pump (13), the second branch pipe (30) of the second shell and tube heat exchanger, and the battery cold plate (17) are sequentially connected in series through a third water circulation pipeline (21); The fourth water tank (15), the fourth water pump (16), the cold air core (18), and the third branch pipe (31) of the second double-tube heat exchanger are sequentially connected in series through a fourth water circulation pipeline (22); One port of the bypass pipeline (24) is connected to the third port of the first three-way valve (6), the other port of the bypass pipeline (24) is connected to the third port of the second three-way valve (7), and the second shell-and-tube heat exchanger main pipe (28) is connected in series in the bypass pipeline (24); The exhaust pressure of the compressor (11) is 115 bar to 123 bar; The carbon dioxide working medium circulation pipeline (23) is connected to each series component by welding.

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