CN211000833U - Automotive heat pump system - Google Patents

Abstract

The utility model relates to the technical field of automobile air conditioners, and discloses an automobile heat pump system. The compression unit, the heating expansion valve and the first external heat exchanger outside the air-conditioning air duct, the compression unit includes the first stage compressor and the second stage compressor; the outlet of the first external heat exchanger, the first stage compressor , The first in-vehicle heat exchanger, the second stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the inlets of the first out-of-vehicle heat exchanger are connected in sequence to form a heating circulation loop. The automobile heat pump system utilizes the first in-vehicle heat exchanger to cool the exhaust gas of the first-stage compressor of the compression unit, and at the same time utilizes the first in-vehicle heat exchanger to preheat the lower temperature air that has just entered the air-conditioning air duct. Heating, effectively recovering the waste heat of intercooling, and improving the heating capacity in winter conditions.

Description

Automotive heat pump system

technical field

The utility model relates to the technical field of automobile air conditioners, in particular to an automobile heat pump system.

Background technique

Under the dual pressure of energy structure transformation and energy saving and emission reduction, pure electric vehicles have gradually become the main development direction of the automobile industry. Compared with traditional fuel vehicles, since there is no engine waste heat to use, electric vehicles put forward additional winter heating requirements for the automotive air conditioning field. At present, electric heaters are generally used for heating auxiliary air conditioning systems in electric vehicles in winter. However, electric heating heating is not only inefficient, but also consumes a lot of on-board electric energy, which seriously affects the cruising range of electric vehicles. Electric vehicles are required to be equipped with higher-capacity batteries, which greatly increases vehicle cost and weight.

Air source heat pump is the best solution to solve the heating demand of electric vehicles at this stage. Existing electric vehicle heat pump systems mostly use single-stage compression mode. When the ambient temperature is low, due to the increase of the pressure ratio, the compressor efficiency is often reduced and the exhaust temperature is too high. The problem of insufficient heating affects the heating effect and cannot meet the winter heating demand in severe cold areas.

Utility model content

The embodiments of the present utility model provide an automobile heat pump system, which is used to solve the problems of low heating efficiency and insufficient heating of the existing electric vehicles, so as to improve the heating effect of the vehicle.

The embodiment of the present utility model provides an automobile heat pump system, which includes a first in-vehicle heat exchanger and a second in-vehicle heat exchanger which are sequentially installed in an air-conditioning air duct of an automobile along the air supply direction, and further includes a An off-road compression unit, a heating expansion valve and a first off-vehicle heat exchanger, the compression unit includes a first-stage compressor and a second-stage compressor; the outlet of the first off-vehicle heat exchanger, the first off-vehicle heat exchanger The inlets of the first-stage compressor, the first in-vehicle heat exchanger, the second-stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the first out-of-vehicle heat exchanger are in sequence connected to form a heating loop.

Wherein, it also includes a second off-vehicle heat exchanger, the first interface of the second off-vehicle heat exchanger is connected to the inlet of the first off-vehicle heat exchanger through a first stop valve, and the second off-vehicle heat exchanger is connected to the inlet of the first off-vehicle heat exchanger. The second interface of the heat exchanger is connected to the outlet of the first off-vehicle heat exchanger through a second shut-off valve.

Among them, it also includes a low-pressure three-way valve, a first medium-pressure three-way valve, a second medium-pressure three-way valve, a high-pressure three-way valve and a refrigeration expansion valve;

The first interface of the low-pressure three-way valve is connected to the outlet of the first off-board heat exchanger, the second interface of the low-pressure three-way valve is connected to the inlet of the first-stage compressor, and the low-pressure three-way valve is connected to the inlet of the first-stage compressor. The third interface of the through valve is connected to the outlet of the first in-vehicle heat exchanger; the refrigeration expansion valve is arranged between the first interface of the low-pressure three-way valve and the inlet of the first in-vehicle heat exchanger;

The first interface of the first medium-pressure three-way valve is connected to the outlet of the first-stage compressor, and the second interface of the first medium-pressure three-way valve is connected to the first in-vehicle heat exchanger. an inlet, the third interface of the first medium-pressure three-way valve is connected to the second interface of the second off-vehicle heat exchanger;

The first interface of the second medium-pressure three-way valve is connected to the outlet of the first in-vehicle heat exchanger, and the second interface of the second medium-pressure three-way valve is connected to the second-stage compressor. an inlet, the third interface of the second medium-pressure three-way valve is connected to the first interface of the second off-vehicle heat exchanger;

The first port of the high-pressure three-way valve is connected to the outlet of the second-stage compressor, the second port of the high-pressure three-way valve is connected to the inlet of the second in-vehicle heat exchanger, and the high-pressure three-way valve is connected to the inlet of the second in-vehicle heat exchanger. The third interface of the through valve is connected to the inlet of the first off-board heat exchanger.

Wherein, it also includes a regenerator, the first heat exchange side of the regenerator is connected in series between the outlet of the first in-vehicle heat exchanger and the third interface of the low pressure three-way valve, the regenerator The second heat exchange side of the heat exchanger is connected in series between the refrigeration expansion valve and the first interface of the low pressure three-way valve.

It also includes a gas-liquid separator, the inlet of the gas-liquid separator is connected to the second port of the low-pressure three-way valve, and the outlet of the gas-liquid separator is connected to the inlet of the first-stage compressor.

Wherein, it also includes an outside fan installed outside the air-conditioning air duct, and the air outlet of the outside fan faces the first outside heat exchanger.

Wherein, it also includes an in-vehicle fan installed in the air-conditioning air duct, and the in-vehicle fan, the first in-vehicle heat exchanger and the second in-vehicle heat exchanger are arranged in sequence along the air supply direction.

Wherein, it also includes a fresh air damper installed at the inlet of the air-conditioning air duct.

Wherein, it also includes a windshield air outlet, a face blowing air outlet and a foot blowing air outlet arranged at the outlet of the air-conditioning air duct.

Wherein, it also includes a direction-adjusting air valve installed in the air-conditioning air duct, and the direction-adjusting air valve is arranged between the first in-vehicle heat exchanger and the second in-vehicle heat exchanger

The automobile heat pump system provided by the embodiment of the present invention includes a first in-vehicle heat exchanger and a second in-vehicle heat exchanger which are sequentially installed in the air-conditioning air duct of the automobile along the air supply direction, and also includes a compressor installed outside the air-conditioning air duct. unit, a heating expansion valve and a first off-vehicle heat exchanger, the compression unit includes a first-stage compressor and a second-stage compressor; the outlet of the first off-vehicle heat exchanger, the first-stage compressor, the first on-board heat exchanger The heater, the second-stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the inlet of the first out-of-vehicle heat exchanger are connected in sequence to form a heating circulation loop. The automobile heat pump system uses the first in-vehicle heat exchanger to cool the exhaust gas of the first-stage compressor of the compression unit, which can avoid the problem that the exhaust gas temperature of the compressor exceeds the limit under extreme low temperature conditions; The heat exchanger preheats the low-temperature air that has just entered the air-conditioning air duct, effectively recovers the waste heat of intercooling, increases the heating capacity in winter conditions, and can significantly improve the performance of the electric vehicle heat pump system under extreme low temperature conditions. Improve the adaptability of the automotive heat pump system to a wide temperature area, and expand the application scope of the automotive heat pump system to extremely cold regions.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative work.

Fig. 1 is the structural representation of a kind of automobile heat pump system in the embodiment of the present utility model;

Fig. 2 is the working flow chart of the automobile heat pump system in the heating mode in the embodiment of the present invention;

Fig. 3 is the working flow chart of the automobile heat pump system in the cooling mode in the embodiment of the present invention;

Fig. 4 is the working flow chart of the automobile heat pump system in the dehumidification mode in the embodiment of the present invention;

Fig. 5 is the working flow chart of the automobile heat pump system in the defrosting mode in the embodiment of the present invention;

Description of reference numbers:

1: Compression unit; 2: The first external heat exchanger; 3: External fan;

4: The first in-vehicle heat exchanger; 5: The second in-vehicle heat exchanger; 6: Gas-liquid separator;

7: Second off-vehicle heat exchanger; 8: Refrigeration expansion valve; 9: Regenerator;

10: high pressure three-way valve; 11: low pressure three-way valve; 12: car fan;

13: Fresh air damper; 14: Directional damper; 15: Heating expansion valve;

16: The first medium pressure three-way valve; 17: The second medium pressure three-way valve; 18: The first stop valve;

19: Second globe valve; 20: Air-conditioning air duct; 21: Fresh air;

22: return air; 23: windshield air outlet; 24: blowing surface air outlet;

25: Air outlet for blowing feet.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. The embodiments described above are a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

In the description of the embodiments of the present utility model, it should be noted that, unless otherwise expressly specified and limited, the terms "first" and "second" are used to clearly describe the numbering of product components and do not represent any substantial difference. The directions of "up", "down", "left" and "right" are based on the directions shown in the drawings. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

It should be noted that, unless otherwise expressly specified and limited, the term "connection" should be understood in a broad sense, for example, it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the utility model can be understood in specific situations.

1 is a schematic structural diagram of an automobile heat pump system in an embodiment of the present invention, and FIG. 2 is a working flow diagram of the automobile heat pump system in a heating mode in an embodiment of the present invention, as shown in FIGS. 1 to 2 . , an automobile heat pump system provided by the embodiment of the present invention includes a first in-vehicle heat exchanger 4 and a second in-vehicle heat exchanger 5 which are sequentially installed in the air-conditioning air duct 20 of the automobile along the air supply direction, and also includes The compression unit 1, the heating expansion valve 15 and the first external heat exchanger 2 are installed outside the air-conditioning air duct 20. The compression unit 1 includes a first-stage compressor and a second-stage compressor, and the first-stage compressor at the right end is Low pressure machine, the second stage compressor on the left end is a high pressure machine. The outlet of the first exterior heat exchanger 2, the first stage compressor, the first interior heat exchanger 4, the second stage compressor, the second interior heat exchanger 5, the heating expansion valve 15 and the first exterior heat exchanger The inlets of the heat exchangers 2 are connected in sequence to form a heating circulation loop.

Specifically, in this embodiment, the air supply direction is from right to left as an example for illustration, and the first in-vehicle heat exchanger 4 is located on the right side of the second in-vehicle heat exchanger 5, closer to the air supply port. In the heating mode, both the first in-vehicle heat exchanger 4 and the second in-vehicle heat exchanger 5 function as coolers. The intake air in the air-conditioning air duct 20 first exchanges heat with the first in-vehicle heat exchanger 4 , the refrigerant gas in the first in-vehicle heat exchanger 4 cools down and releases heat, and the intake air outside the first in-vehicle heat exchanger 4 . The wind is preheated. Then, the preheated intake air exchanges heat with the second in-vehicle heat exchanger 5, and the intake air is further heated into high-temperature air that can be used for heating, and finally sent to the user end to achieve the purpose of heating the vehicle compartment. . The refrigerant may be R134a, R1234yf or CO ₂ and other refrigerants, and the refrigerant in this embodiment is carbon dioxide as a natural working medium.

As shown in FIG. 2 , the low-temperature and low-pressure refrigerant gas is compressed by the first-stage compressor of the compression unit 1 to become medium-temperature and high-pressure gas, and then the exhaust gas of the first-stage compressor flows into the first stage installed in the air-conditioning air duct 20 . The in-vehicle heat exchanger 4 is cooled by the cold air that has just been sent into the air-conditioning duct 20, and then becomes a low-temperature and medium-pressure refrigerant gas. The low-temperature and medium-pressure refrigerant gas flows back to the compression unit 1 for a second compression, and is compressed into a high-temperature and high-pressure refrigerant vapor by the second-stage compressor. The high-temperature and high-pressure refrigerant vapor discharged from the second-stage compressor flows into the second in-vehicle heat exchanger 5 installed in the air-conditioning air duct 20, and is preheated by the first in-vehicle heat exchanger 4 in the air-conditioning air duct 20. The air is cooled, and then flows through the heating expansion valve 15 to expand into a low-temperature and low-pressure gas-liquid two-phase refrigerant. Then the low-temperature and low-pressure refrigerant enters the first off-vehicle heat exchanger 2, evaporates and changes phase in the first off-vehicle heat exchanger 2, becomes a low-temperature and low-pressure refrigerant gas, and then flows to the first-stage compression of the compression unit 1 again. machine to complete a refrigerant cycle.

An automobile heat pump system provided by this embodiment includes a first in-vehicle heat exchanger and a second in-vehicle heat exchanger which are sequentially installed in an air-conditioning air duct of the automobile along the air supply direction, and also includes a compressor installed outside the air-conditioning air duct. unit, a heating expansion valve and a first off-vehicle heat exchanger, the compression unit includes a first-stage compressor and a second-stage compressor; the outlet of the first off-vehicle heat exchanger, the first-stage compressor, the first on-board heat exchanger The heater, the second-stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the inlet of the first out-of-vehicle heat exchanger are connected in sequence to form a heating circulation loop. The automobile heat pump system uses the first in-vehicle heat exchanger to cool the exhaust gas of the first-stage compressor of the compression unit, which can avoid the problem that the exhaust gas temperature of the compressor exceeds the limit under extreme low temperature conditions; The heat exchanger preheats the low-temperature air that has just entered the air-conditioning air duct, effectively recovers the waste heat of intercooling, increases the heating capacity in winter conditions, and can significantly improve the performance of the electric vehicle heat pump system under extreme low temperature conditions. Improve the adaptability of the automotive heat pump system to a wide temperature area, and expand the application scope of the automotive heat pump system to extremely cold regions.

Further, as shown in FIGS. 1 to 2 , it also includes a second off-vehicle heat exchanger 7 , and the first interface (ie, the left end interface) of the second off-vehicle heat exchanger 7 is connected to the first The inlet of the off-vehicle heat exchanger 2 and the second interface (ie, the right end interface) of the second off-vehicle heat exchanger 7 are connected to the outlet of the first off-vehicle heat exchanger 2 through the second stop valve 19 . That is, the second off-vehicle heat exchanger 7 is connected in parallel with the first off-vehicle heat exchanger 2 .

Specifically, the first off-vehicle heat exchanger 2 and the second off-vehicle heat exchanger 7 may be placed side by side at the front of the vehicle. The working process when the second off-vehicle heat exchanger 7 is put into the heating condition is basically the same as that of the above-mentioned embodiment, the difference is that the low-temperature and low-pressure refrigerant expanded by the heating expansion valve 15 is divided into two fluids, and a part directly enters the The first off-board heat exchanger 2 conducts heat exchange, and the other part flows into the second off-board heat exchanger 7 through the first shut-off valve 18 for heat exchange. After the evaporation phase changes in the second off-vehicle heat exchanger 7 and becomes a low-temperature and low-pressure gaseous refrigerant, it is re-converged into a fluid through the second cut-off valve 19 that is turned on. By using the first off-vehicle heat exchanger 2 and the second off-vehicle heat exchanger 7 as evaporators in parallel, the heat exchange area of the evaporator can be effectively increased, the heat absorption of the evaporator can be increased, and the efficiency of winter working conditions can be improved. heating performance.

Further, as shown in FIGS. 1 to 5 , it also includes a low-pressure three-way valve 11 , a first medium-pressure three-way valve 16 , a second medium-pressure three-way valve 17 , a high-pressure three-way valve 10 and a refrigeration expansion valve 8 .

The first port (ie the a port) of the low pressure three-way valve 11 is connected to the outlet of the first external heat exchanger 2, and the second port (ie the b port) of the low pressure three-way valve 11 is connected to the inlet of the first stage compressor , the third port (ie the c port) of the low pressure three-way valve 11 is connected to the outlet of the first in-vehicle heat exchanger 4 . The refrigeration expansion valve 8 is arranged between the first port (ie the a port) of the low pressure three-way valve 11 and the inlet of the first in-vehicle heat exchanger 4 .

The first port (ie the a port) of the first medium pressure three-way valve 16 is connected to the outlet of the first stage compressor, and the second port (ie the b port) of the first medium pressure three-way valve 16 is connected to the first vehicle interior At the inlet of the heat exchanger 4 , the third port (ie, the c port) of the first medium-pressure three-way valve 16 is connected to the second port (ie, the right port) of the second off-vehicle heat exchanger 7 .

The first port (ie the a port) of the second medium pressure three-way valve 17 is connected to the outlet of the first in-vehicle heat exchanger 4, and the second port (ie the b port) of the second medium pressure three-way valve 17 is connected to the first port The inlet of the secondary compressor, the third port (ie the c port) of the second medium pressure three-way valve 17 is connected to the first port (ie the left port) of the second off-board heat exchanger 7 .

The first port (ie, the a port) of the high-pressure three-way valve 10 is connected to the outlet of the second-stage compressor, and the second port (ie, the b port) of the high-pressure three-way valve is connected to the inlet of the second in-vehicle heat exchanger. The third port (ie, the c port) of the three-way valve is connected to the inlet of the first off-vehicle heat exchanger.

Specifically, the low-pressure three-way valve 11 , the first medium-pressure three-way valve 16 , the second medium-pressure three-way valve 17 and the high-pressure three-way valve 10 can all use electric valves. By setting four three-way valves, the connection interface of the three-way valve can be switched in time according to different working conditions to meet the needs of users.

As shown in FIG. 2 , which is the working flow chart in the heating mode, at this time, the first shut-off valve 18 and the second shut-off valve 19 are both opened, the low-pressure three-way valve 11 is connected to the a and b interfaces, and the first medium-pressure three-way valve The through valve 16 communicates with the a and b ports, the second medium pressure three-way valve 17 communicates with the a and b ports, and the high pressure three-way valve 10 communicates with the a and b ports.

As shown in FIG. 3 , which is the working flow chart in the cooling mode, at this time, the first shut-off valve 18 and the second shut-off valve 19 are both closed, the low-pressure three-way valve 11 is connected to the b and c interfaces, and the first medium-pressure three-way The valve 16 communicates with ports a and c, the second medium pressure three-way valve 17 communicates with ports b and c, and the high pressure three-way valve 10 communicates with ports a and c.

As shown in FIG. 4 , which is the working flow chart in the dehumidification mode, at this time, the first shut-off valve 18 and the second shut-off valve 19 are both closed, the low-pressure three-way valve 11 is connected to the b and c interfaces, and the first medium-pressure three-way The valve 16 communicates with the a and c ports, the second medium pressure three-way valve 17 communicates with the b and c ports, and the high pressure three-way valve 10 communicates with the a and b ports.

As shown in FIG. 5 , which is the working flow chart in the defrosting mode, at this time, the first shut-off valve 18 and the second shut-off valve 19 are both closed, the low-pressure three-way valve 11 is connected to the b and c interfaces, and the first medium pressure three The through valve 16 communicates with ports a and c, the second medium pressure three-way valve 17 communicates with ports b and c, and the high pressure three-way valve 10 communicates with ports a and c.

Further, as shown in FIG. 3 , a regenerator 9 is also included, and the first heat exchange side (left passage) of the regenerator 9 is connected in series to the outlet of the first in-vehicle heat exchanger 4 and the low-pressure three-way valve 11 . Between the third interface (ie the c interface) of the regenerator 9, the second heat exchange side (the right channel) of the regenerator 9 is connected in series between the refrigeration expansion valve 8 and the first interface (ie the a interface) of the low pressure three-way valve 11 That is, the second heat exchange side of the regenerator 9 is connected in series between the refrigeration expansion valve 8 and the outlet of the first off-vehicle heat exchanger 2 .

Specifically, in the cooling mode, the regenerator 9 is put into use. As shown in FIG. 3 , the exhaust gas of the first-stage compressor of the compression unit 1 is communicated with the second external heat exchanger 7 through the first medium-pressure three-way valve 16 and the second medium-pressure three-way valve 17, and the refrigerant passes through the first medium-pressure three-way valve 16 and the second medium-pressure three-way valve 17. After the compression of the first-stage compressor, it reaches a high temperature and medium pressure state; then the gas that becomes a low-temperature and medium-pressure gas after being cooled by the second off-board heat exchanger 7 flows into the second-stage compressor, and becomes a high-temperature gas after being compressed by the second-stage compressor. High-pressure gas; the high-temperature and high-pressure gas discharged from the second-stage compressor flows to the first outside heat exchanger 2, and is cooled by the air blown by the outside fan 3 to become low-temperature and high-pressure liquid, and then enters the regenerator 9 After being throttled by the refrigeration expansion valve 8, it becomes a low-temperature and low-pressure two-phase fluid, and then evaporates in the first in-vehicle heat exchanger 4 to absorb the heat of the air in the air-conditioning duct, To achieve the purpose of cooling the car room. The temperature of the first heat exchange side in the regenerator 9 is lower than the temperature of the second heat exchange side, so it is possible to pre-cool the refrigerant in the first heat exchange side of the regenerator 9, and reduce the amount of refrigerant The temperature before throttling and the dryness after throttling increase the cooling capacity and improve the cooling effect.

The exhaust gas temperature of the compression unit 1 is reduced by the method of intercooling the exhaust gas of the first-stage compressor of the compression unit 1 by the second off-vehicle heat exchanger 7 installed at the front of the vehicle, so as to ensure the working condition of a large pressure ratio in an extremely high temperature environment The safe use of the lower compression unit 1 broadens the applicability of the automobile heat pump system to high temperature refrigeration conditions.

More specifically, since the first off-vehicle heat exchanger 2 and the second off-vehicle heat exchanger 7 are arranged side by side, the off-vehicle fan 3 can simultaneously cool the first off-vehicle heat exchanger 2 and the second off-vehicle heat exchanger 7 . Cool down.

Further, as shown in FIG. 1, it also includes a gas-liquid separator 6, the inlet of the gas-liquid separator 6 is connected to the second interface (ie the b interface) of the low-pressure three-way valve 11, and the outlet of the gas-liquid separator 6 is connected to Inlet of the first stage compressor. By arranging the gas-liquid separator 6, the gas and the liquid can be separated as much as possible, so as to prevent the liquid from entering the compression unit 1 and damage the compressor.

Further, as shown in FIG. 1 , it also includes an outside fan 3 installed outside the air-conditioning air duct 20 , and the air outlet of the outside fan 3 faces the first outside heat exchanger 2 .

Further, as shown in FIG. 1 , an in-vehicle fan 12 installed in the air-conditioning air duct 20 is also included, and the in-vehicle fan 12 is installed on the right side of the first in-vehicle heat exchanger 4 to transport cold air from right to left . Both the interior fan 12 and the exterior fan 3 can be electric fans.

Further, as shown in FIG. 1 , it also includes a fresh air damper 13 installed at the inlet of the air-conditioning air duct 20. Using the fresh air damper 13, it is possible to select whether the fresh air 21 or the return air 22 is blown in, so as to carry out fresh air circulation or vehicle ventilation. Internal circulation.

Further, as shown in FIG. 1, it also includes a windshield air outlet 23, a face blowing air outlet 24 and a foot blowing air outlet 25 arranged at the outlet of the air-conditioning air duct 20, wherein the windshield air outlet 23 faces upward, It is used to send air to the windshield in front of the car; the air outlet 24 of the face blowing is facing the middle, which is used to send air to the driver's face; the air outlet 25 of the foot blowing is facing down, which is used to send air to the driver's feet.

Further, as shown in FIG. 1 , a direction regulating air valve 14 is also included, and the direction regulating air valve 14 is installed between the first in-vehicle heat exchanger 4 and the second in-vehicle heat exchanger 5 for adjusting the wind direction. Both the direction regulating air valve 14 and the fresh air air valve 13 can use electric valves.

In a specific embodiment, a control method for an automobile heat pump system is also provided. As shown in FIG. 2 , the automobile heat pump system adopts the above-mentioned automobile heat pump system. The control method includes a heating mode, and the heating mode includes: connecting a first The outlet of the off-board heat exchanger 2, the first stage compressor, the first on-board heat exchanger 4, the second stage compressor, the second on-board heat exchanger 5, the heating expansion valve 15 and the first off-board heat exchanger Import of device 2.

Further, as shown in Figure 2, the heating mode also includes:

Open the first cut-off valve 18 and the second cut-off valve 19, connect the a and b ports of the low-pressure three-way valve 11, connect the a and b ports of the first medium-pressure three-way valve 16, and communicate with the second medium-pressure three-way valve 17. The a and b ports are connected to the a and b ports of the high-pressure three-way valve 10 .

Further, as shown in FIG. 3 , a cooling mode is also included, and the cooling mode includes:

Close the first cut-off valve 18 and the second cut-off valve 19, connect the b and c ports of the low-pressure three-way valve 11, connect the a and c ports of the first medium-pressure three-way valve 16, and communicate with the second medium-pressure three-way valve 17. The b and c ports are connected to the a and c ports of the high-pressure three-way valve 10 .

Further, as shown in Figure 4, a dehumidification mode is also included, and the dehumidification mode includes:

Close the first cut-off valve 18 and the second cut-off valve 19, connect the b and c ports of the low-pressure three-way valve 11, connect the a and c ports of the first medium-pressure three-way valve 16, and communicate with the second medium-pressure three-way valve 17. The b and c ports are connected to the a and b ports of the high-pressure three-way valve 10 .

Specifically, the refrigerant becomes a low-temperature and low-pressure two-phase fluid after being throttled by the refrigeration expansion valve 8, and then evaporates and absorbs heat in the first in-vehicle heat exchanger 4, so that the temperature of the outer surface of the first in-vehicle heat exchanger 4 is Reach a lower state; after the refrigerant evaporates and absorbs heat, it becomes a low-temperature and low-pressure vapor, which flows into the compression unit 1 through the regenerator 9 and the gas-liquid separator 6, and is then compressed into a high-temperature and medium-pressure gaseous state by the first-stage compressor; The compressed refrigerant is cooled by the second off-vehicle heat exchanger 7 to become a low-temperature and medium-pressure gas, and then flows into the second-stage compressor. Heater 5 is cooled by the air in air duct 20 and then flows into first external heat exchanger 2 for further cooling; then flows to regenerator 9 and refrigeration expansion valve 8 to complete a cycle. The high-humidity air blown in by the in-vehicle fan 12 in the air-conditioning air duct 20 flows through the surface of the first in-vehicle heat exchanger 4 with a lower temperature, and the humidity is reduced while being cooled; then the low-temperature and low-humidity air flows through When the second in-vehicle heat exchanger 5 is used, it is heated into air with higher temperature and lower humidity, and then sent to the vehicle compartment, so as to achieve the purpose of dehumidifying the air in the vehicle compartment.

Further, as shown in Figure 5, a defrosting mode is also included, and the defrosting mode includes:

Close the first cut-off valve 18 and the second cut-off valve 19, connect the b and c ports of the low-pressure three-way valve 11, connect the a and c ports of the first medium-pressure three-way valve 16, and communicate with the second medium-pressure three-way valve 17. The b and c ports are connected to the a and c ports of the high-pressure three-way valve 10 . The flow direction of the refrigerant in the defrosting mode is the same as the refrigerant flow direction in the cooling mode. Heating with the first off-vehicle heat exchanger 2 makes the frost layer adhering to the surfaces of the second off-vehicle heat exchanger 7 and the first off-vehicle heat exchanger 2 gradually melt, so as to achieve the purpose of defrosting. This mode is mainly used in winter conditions. After using the heating mode for a period of time, defrosting is performed by enabling the defrosting mode to avoid affecting the heat exchange performance of the heat exchanger, so that the system can maintain high-efficiency operation for a long time.

It can be seen from the above embodiments that the automobile heat pump system provided by the present invention includes a first in-vehicle heat exchanger and a second in-vehicle heat exchanger which are sequentially installed in the air-conditioning air duct of the automobile along the air supply direction, and also includes installation The compression unit, the heating expansion valve and the first external heat exchanger outside the air-conditioning air duct, the compression unit includes the first stage compressor and the second stage compressor; the outlet of the first external heat exchanger, the first stage compressor , The first in-vehicle heat exchanger, the second-stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the inlets of the first out-of-vehicle heat exchanger are connected in sequence to form a heating circulation loop. The automobile heat pump system uses the first in-vehicle heat exchanger to cool the exhaust gas of the first-stage compressor of the compression unit, which can avoid the problem that the exhaust gas temperature of the compressor exceeds the limit under extreme low temperature conditions; The heat exchanger preheats the low-temperature air that has just entered the air-conditioning air duct, effectively recovers the waste heat of intercooling, increases the heating capacity in winter conditions, and can significantly improve the performance of the electric vehicle heat pump system under extreme low temperature conditions. Improve the adaptability of the automotive heat pump system to a wide temperature area, and expand the application scope of the automotive heat pump system to extremely cold regions.

Furthermore, the electric vehicle heat pump system provided by the utility model takes into account the performance of cooling and heating conditions, and can significantly improve the performance of the electric vehicle heat pump system under extreme high temperature conditions and extreme low temperature conditions.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model, but not to limit them; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the spirit of the technical solutions of the embodiments of the present invention and range.

Claims (10)

1. An automobile heat pump system, comprising the first in-vehicle heat exchanger and the second in-vehicle heat exchanger which are sequentially installed in the air-conditioning air duct of the automobile along the air supply direction, it is characterized in that, also comprises being installed in the described air-conditioning air duct. An off-road compression unit, a heating expansion valve and a first off-vehicle heat exchanger, the compression unit includes a first-stage compressor and a second-stage compressor; the outlet of the first off-vehicle heat exchanger, the first off-vehicle heat exchanger The inlets of the first-stage compressor, the first in-vehicle heat exchanger, the second-stage compressor, the second in-vehicle heat exchanger, the heating expansion valve and the first out-of-vehicle heat exchanger are in sequence connected to form a heating loop. 2 . The automobile heat pump system according to claim 1 , further comprising a second off-vehicle heat exchanger, wherein the first interface of the second off-vehicle heat exchanger is connected to the second external heat exchanger through a first stop valve. The inlet of an off-board heat exchanger, and the second interface of the second off-board heat exchanger is connected to the outlet of the first off-board heat exchanger through a second shut-off valve. 3. The automobile heat pump system according to claim 2, further comprising a low-pressure three-way valve, a first medium-pressure three-way valve, a second medium-pressure three-way valve, a high-pressure three-way valve and a refrigeration expansion valve; The first interface of the low-pressure three-way valve is connected to the outlet of the first off-board heat exchanger, the second interface of the low-pressure three-way valve is connected to the inlet of the first-stage compressor, and the low-pressure three-way valve is connected to the inlet of the first-stage compressor. The third interface of the through valve is connected to the outlet of the first in-vehicle heat exchanger; the refrigeration expansion valve is arranged between the first interface of the low-pressure three-way valve and the inlet of the first in-vehicle heat exchanger; The first interface of the first medium-pressure three-way valve is connected to the outlet of the first-stage compressor, and the second interface of the first medium-pressure three-way valve is connected to the first in-vehicle heat exchanger. an inlet, the third interface of the first medium-pressure three-way valve is connected to the second interface of the second off-vehicle heat exchanger; The first interface of the second medium-pressure three-way valve is connected to the outlet of the first in-vehicle heat exchanger, and the second interface of the second medium-pressure three-way valve is connected to the second-stage compressor. an inlet, the third interface of the second medium-pressure three-way valve is connected to the first interface of the second off-vehicle heat exchanger; The first port of the high-pressure three-way valve is connected to the outlet of the second-stage compressor, the second port of the high-pressure three-way valve is connected to the inlet of the second in-vehicle heat exchanger, and the high-pressure three-way valve is connected to the inlet of the second in-vehicle heat exchanger. The third interface of the through valve is connected to the inlet of the first off-board heat exchanger. 4 . The automobile heat pump system according to claim 3 , further comprising a regenerator, the first heat exchange side of the regenerator is connected in series to the outlet of the first in-vehicle heat exchanger and the Between the third ports of the low-pressure three-way valve, the second heat exchange side of the regenerator is connected in series between the refrigeration expansion valve and the first port of the low-pressure three-way valve. 5 . The automobile heat pump system according to claim 3 , further comprising a gas-liquid separator, the inlet of the gas-liquid separator is connected to the second interface of the low-pressure three-way valve, and the gas-liquid separation The outlet of the compressor is connected to the inlet of the first stage compressor. 6 . The automobile heat pump system according to claim 1 , further comprising an outside fan installed outside the air-conditioning air duct, the air outlet of the outside fan facing the first outside heat exchanger. 7 . 7 . The automobile heat pump system according to claim 1 , further comprising an in-vehicle fan installed in the air-conditioning air duct, the in-vehicle fan, the first in-vehicle heat exchanger and the first in-vehicle heat exchanger. 8 . Two in-vehicle heat exchangers are arranged in sequence along the air supply direction. 8 . The automobile heat pump system according to claim 1 , further comprising a fresh air damper installed at the inlet of the air-conditioning air duct. 9 . 9 . The automobile heat pump system according to claim 1 , further comprising a windshield air outlet, a face blowing air outlet and a foot blowing air outlet arranged at the outlet of the air-conditioning air duct. 10 . 10 . The automobile heat pump system according to claim 1 , further comprising a direction-adjusting air valve installed in the air-conditioning air duct, and the direction-adjusting air valve is arranged on the first in-vehicle heat exchanger and the between the second in-vehicle heat exchangers.

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