A thermal management system for a coupled fast charging station and a vehicle

Abstract

The present invention discloses a thermal management system for a coupled fast-charging charging station and a whole vehicle, which relates to the technical field of fast charging of new energy vehicles. The present invention includes a whole vehicle thermal management system, a charging station thermal management system, and a heat exchange device. The heat exchange device is arranged on the vehicle. The charging station thermal management system includes a first circulation unit and a second circulation unit. The first circulation unit is composed of a first compressor, a condenser, a first throttling mechanism, and a first evaporator that are connected in sequence to form a first cold / heat carrier medium circulation loop. Through the newly added heat exchange device, in cooperation with the charging gun water circuit composed of an inflow pipeline and a return pipeline, and through a quick plug connector, the energy exchange between the charging station thermal management system and the whole vehicle thermal management system can be realized. Through the combination, cooling or heating in multiple modes can be realized, which is beneficial to temperature control or heat regulation during the fast charging process. The cooperation of the two avoids the problem of overabundance or shortage of cooling resources caused by the single use of each of them.

Description

Technical Field

[0001] The present invention belongs to the technical field of fast charging for new energy vehicles, and particularly relates to a thermal management system for coupling a fast charging station and a whole vehicle. Background Art

[0002] Currently, with the rapid development of new energy vehicle technology, the ownership of new energy vehicles is increasing continuously, and users have higher and higher requirements for the charging efficiency of new energy vehicles. The demand for battery fast charging technology is becoming increasingly urgent. However, due to the constraints of two major problems, namely the thermal management of the whole vehicle and the thermal management of fast charging equipment, the fast charging technology of new energy vehicles has not been widely popularized and applied at present.

[0003] When a charging pile rapidly charges the battery of a new energy vehicle, compared with ordinary slow charging, the heat generated by the battery will increase geometrically. For the battery, the accumulation of high-density heat will accelerate battery aging. Therefore, the battery cooling problem during the fast charging process has become the main factor blocking the battery charging speed.

[0004] During the fast charging process, a large current will be generated, resulting in more heat. The two major systems (the charging station thermal management system and the whole vehicle thermal management system) cool separately. Among them, it is somewhat wasteful of cooling resources for the charging station thermal management system to only cool the charging gun and the cable. And during charging, due to limited heat dissipation capacity, the whole vehicle thermal management system cannot meet the requirements for cooling the battery during the fast charging process. If the refrigeration performance of the whole vehicle thermal management system is improved alone (each sub-component becomes larger accordingly), there will be defects such as occupying space, high cost, large weight, low utilization rate (only applicable to its own vehicle), and poor user experience.

[0005] If the charging station thermal management system and the whole vehicle thermal management system are combined for energy exchange, the problems of excessive cooling in the charging station and insufficient cooling effect of the whole vehicle can be avoided. Therefore, designing a combined thermal management system for the two is a problem that needs to be solved by the workers in this field.

[0006] Moreover, when the battery temperature is too low, the charging speed of the battery will also be affected and reduced. And the heating performance in the existing charging station thermal management system and the whole vehicle thermal management system is limited, so it cannot achieve normal charging effects and efficiency under the influence of low-temperature environments, and cannot meet the fast charging standard, seriously affecting the customer experience. Therefore, designing a cooling system with an active heating function is a problem that needs to be solved by the workers in this field. Summary of the Invention

[0007] The object of the present invention is to provide a thermal management system for a coupled fast - charging charging station and a whole vehicle. Through the newly added heat exchange equipment, in cooperation with the charging gun water circuit composed of an inflow pipeline and a return pipeline, energy exchange between the thermal management system of the charging station and the thermal management system of the whole vehicle can be achieved through quick - plug connectors. Through combination, cooling or heating in multiple modes can be realized, which is conducive to temperature control or heat regulation during the fast - charging process. The cooperation of the two avoids the problems of over - surplus or shortage of cooling resources caused by their single use respectively.

[0008] To solve the above - mentioned technical problems, the present invention is realized through the following technical solutions:

[0009] The present invention relates to a thermal management system for a coupled fast - charging charging station and a whole vehicle, including a whole - vehicle thermal management system, a charging - station thermal management system, and a heat exchange equipment, and the heat exchange equipment is arranged on the vehicle;

[0010] The charging - station thermal management system includes a first circulation unit and a second circulation unit;

[0011] The first circulation unit is composed of a first compressor, a condenser, a first throttling mechanism, and a first evaporator that are connected in sequence to form a first secondary coolant / heat - carrying medium circulation loop;

[0012] The second circulation unit includes a pipeline connector, a radiator, a heater, a first water pump, and a charging gun water circuit;

[0013] The outlet end of the first water pump and the second secondary coolant / heat - carrying medium inlet end of the first evaporator are both connected with a main pipe, and the pipeline connector, the radiator, and the heater are connected in parallel between the two main pipes in sequence;

[0014] The charging gun water circuit includes an inflow pipeline and a return pipeline. The inlet of the inflow pipeline is connected to the second secondary coolant / heat - carrying medium outlet end of the first evaporator, and the outlet of the return pipeline is connected to the inlet of the first water pump;

[0015] A set of connecting pipes are respectively connected to the outlet of the inflow pipeline and the inlet of the return pipeline through quick - plug connectors, and the two connecting pipes are respectively connected to the inlet and outlet of the first secondary coolant / heat - carrying medium of the heat exchange equipment. The connection points of the connecting pipes and the quick - plug connectors are set at the position of the vehicle charging port;

[0016] The whole - vehicle thermal management system includes a third circulation unit and a fourth circulation unit;

[0017] The third circulation unit includes a battery cooler, a second water pump, and a power battery circuit;

[0018] The power battery circuit, the second secondary coolant / heat carrier circulation circuit of the heat exchange device, the first secondary coolant / heat carrier circulation circuit of the battery cooler, and the second water pump are connected in sequence to form a circulation circuit, and the second secondary coolant / heat carrier circulation circuit of the battery cooler is connected to the fourth circulation unit;

[0019] A connecting pipe is provided on the pipeline between the heat exchange device and the battery cooler through a third three-way valve. The other end of the connecting pipe is connected between the second water pump and the battery cooler, and a PTC heater is provided on the connecting pipe.

[0020] Further, the fourth circulation unit includes a gas-liquid separator, a second compressor, an internal condenser, a parallel pipe, an external condenser, and a second evaporator that are connected in sequence to form a circulation circuit. First cut-off valves and second throttling mechanisms are respectively provided on the two pipe bodies of the parallel pipe. A first external connecting pipe is provided on the pipeline between the external condenser and the second evaporator. The other end of the first external connecting pipe is connected to the inlet end of the second secondary coolant / heat carrier of the battery cooler, and the outlet end of the second secondary coolant / heat carrier of the battery cooler is connected to the pipeline between the second evaporator and the gas-liquid separator.

[0021] Further, a second external connecting pipe is connected to the pipeline between the external condenser and the battery cooler. The other end of the second external connecting pipe is connected to the pipeline between the gas-liquid separator and the second evaporator, and a second cut-off valve is provided on the second external connecting pipe.

[0022] Further, a third throttling mechanism is provided on the first external connecting pipe, and a fourth throttling mechanism is provided on the pipeline between the external condenser and the second evaporator. The fourth throttling mechanism is located at a position behind the first external connecting pipe.

[0023] Further, a first three-way valve is provided between the main pipes of the heater, the radiator, and the first water pump. The pipeline connector is connected to the main pipe, and the connection point is located between the first three-way valve and the first water pump.

[0024] Further, a second three-way valve is connected to the main pipe between the first evaporator and the heater. The end of the pipeline connector is connected to the other interface of the second three-way valve.

[0025] The present invention has the following beneficial effects:

[0026] 1. The present invention realizes the energy exchange between the charging station thermal management system and the vehicle thermal management system through the newly added heat exchange device and the charging gun water circuit composed of the inflow pipeline and the return pipeline. Through the quick connector, the cooling or heating in multiple modes can be realized. The cooling range is relatively large, which is beneficial to the temperature control or heat regulation during the fast charging process, improves the charging efficiency, and ensures the service life of the charging gun, cable, and battery. The cooperation of the two avoids the problem of overabundant or insufficient cooling resources caused by the single use of each, solves the problem of high power requirements for the subsequent vehicle cooling system due to excessive refrigeration demand, reduces the occupation of space and weight, and lowers the cost.

[0027] 2. The present invention realizes the connection between the inflow pipeline and the return pipeline and the heat exchange device through the quick connector, and can realize the connection between the charging gun water circuit and the heat exchange device when the charging gun is coupled, which is beneficial to the operation of the staff.

[0028] 3. By setting heaters in the second circulation unit and the third circulation unit, the present invention can heat the medium in the circuit, which can be used for active heating in low-temperature environments and avoid the problem of low charging efficiency caused by low temperature.

[0029] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.

[0031] Figure 1 It is the system principle block diagram of a thermal management system for a coupled fast-charging charging station and a vehicle of the present invention;

[0032] Figure 2 It is the system principle block diagram in cooling mode 1;

[0033] Figure 3 It is the system principle block diagram in cooling mode 2;

[0034] Figure 4 It is the system principle block diagram in cooling mode 3;

[0035] Figure 5 It is the system principle block diagram in heating mode 1;

[0036] Figure 6 It is the system principle block diagram in heating mode 2;

[0037] In the attached drawings, the list of components represented by each reference numeral is as follows:

[0038] 1 - First circulation unit, 2 - Pipeline connector, 3 - Radiator, 4 - Heater, 5 - First water pump, 6 - Charging gun water circuit, 7 - Battery cooler, 8 - Second water pump, 9 - Heat exchange device, 10 - Power battery circuit, 11 - Connecting pipe, 12 - PTC heater, 13 - Gas-liquid separator, 14 - Second compressor, 15 - Internal condenser, 16 - External condenser, 17 - Second evaporator, 18 - First cut-off valve, 19 - Second throttling mechanism, 20 - First external connecting pipe, 21 - Second external connecting pipe, 22 - Second cut-off valve, 23 - Third throttling mechanism, 24 - Fourth throttling mechanism, 25 - Connecting pipe, 26 - Third three-way valve, 101 - First compressor, 102 - Condenser, 103 - First throttling mechanism, 104 - First evaporator, 105 - Main pipe, 106 - First three-way valve, 107 - Second three-way valve, 601 - Inflow pipeline, 602 - Return pipeline. Detailed implementation mode

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0040] Please refer to Figure 1 As shown, the present invention is a thermal management system for coupling a fast charging station and a whole vehicle, including a whole vehicle thermal management system, a charging station thermal management system and a heat exchange device 9, and the heat exchange device 9 is arranged on the vehicle;

[0041] The charging station thermal management system includes a first circulation unit 1 and a second circulation unit;

[0042] The first circulation unit 1 is composed of a first compressor 101, a condenser 102, a first throttling mechanism 103 and a first evaporator 104 which are connected in sequence to form a first cold / hot medium circulation loop;

[0043] The second circulation unit includes a pipeline connector 2, a radiator 3, a heater 4, a first water pump 5 and a charging gun water circuit 6;

[0044] The outlet end of the first water pump 5 and the second cold / hot medium inlet end of the first evaporator 104 are both connected with a main pipe 105, and the pipeline connector 2, the radiator 3 and the heater 4 are connected in parallel between the two main pipes 105 in sequence;

[0045] The charging gun water circuit 6 includes an inflow pipeline 601 and a return pipeline 602. The inlet of the inflow pipeline 601 is connected to the second secondary coolant / heat carrier medium outlet end of the first evaporator 104, and the outlet of the return pipeline 602 is connected to the inlet of the first water pump 5;

[0046] A set of connecting pipes 25 are respectively connected to the outlet of the inflow pipeline 601 and the inlet of the return pipeline 602 through quick connectors. The two connecting pipes 25 are respectively connected to the inlet and outlet of the first secondary coolant / heat carrier medium of the heat exchange device 9, and the connection points of the connecting pipes 25 and the quick connectors are set at the position of the vehicle charging port;

[0047] The vehicle thermal management system includes a third circulation unit and a fourth circulation unit;

[0048] The third circulation unit includes a battery cooler 7, a second water pump 8, and a power battery circuit 10;

[0049] The power battery circuit 10, the second secondary coolant / heat carrier medium circulation circuit of the heat exchange device 9, the first secondary coolant / heat carrier medium circulation circuit of the battery cooler 7, and the second water pump 8 are connected in sequence to form a circulation circuit. The second secondary coolant / heat carrier medium circulation circuit of the battery cooler 7 is connected to the fourth circulation unit;

[0050] A connecting pipe 11 is provided on the pipeline between the heat exchange device 9 and the battery cooler 7 through a third three-way valve 26. The other end of the connecting pipe 11 is connected between the second water pump 8 and the battery cooler 7, and a PTC heater 12 is provided on the connecting pipe 11.

[0051] Among them, as Figure 1 shown, the fourth circulation unit includes a gas-liquid separator 13, a second compressor 14, an internal condenser 15, a parallel pipe, an external condenser 16, and a second evaporator 17 that are connected in sequence to form a circulation circuit. First cut-off valves 18 and second throttling mechanisms 19 are respectively provided on the two pipe bodies of the parallel pipe. A first external connecting pipe 20 is provided on the pipeline between the external condenser 16 and the second evaporator 17. The other end of the first external connecting pipe 20 is connected to the inlet end of the second secondary coolant / heat carrier medium of the battery cooler 7, and the outlet end of the second secondary coolant / heat carrier medium of the battery cooler 7 is connected to the pipeline between the second evaporator 17 and the gas-liquid separator 13.

[0052] Among them, as Figure 1 shown, a second external connecting pipe 21 is connected to the pipeline between the external condenser 16 and the battery cooler 7. The other end of the second external connecting pipe 21 is connected to the pipeline between the gas-liquid separator 13 and the second evaporator 17, and a second cut-off valve 22 is provided on the second external connecting pipe 21.

[0053] Among them, as Figure 1As shown, a third throttling mechanism 23 is provided on the first external connecting pipe 20, and a fourth throttling mechanism 24 is provided on the pipeline between the external condenser 16 and the second evaporator 17. The fourth throttling mechanism 24 is located at the rear position of the first external connecting pipe 20.

[0054] As shown in Figure 1 As shown, a first three-way valve 106 is provided between the heater 4, the radiator 3 and the main pipe 105 on the first water pump 5. The pipeline connector 2 is connected to the main pipe 105 and the connection point is between the first three-way valve 106 and the first water pump 5.

[0055] As shown in Figure 1 As shown, a second three-way valve 107 is connected to the main pipe 105 between the first evaporator 104 and the heater 4. The end of the pipeline connector 2 is connected to the other interface of the second three-way valve 107

[0056] Among them, for the vehicle thermal management system, the internal condenser 15 and the second evaporator 17 are installed in the air conditioning box.

[0057] Among them, the application of the vehicle thermal management system is as follows:

[0058] (1) Battery refrigeration cycle: Open the first cut-off valve 18, close the second cut-off valve 22 and the fourth throttling mechanism 24. The second compressor 14 discharges high-temperature and high-pressure gaseous refrigerant, which passes through the internal condenser 15 and the first cut-off valve 18 in the air conditioning box and enters the external condenser 16 to become high-pressure liquid refrigerant. After throttling by the third throttling mechanism 23, it becomes low-temperature and low-pressure two-phase refrigerant and enters the battery cooler 7. The refrigerant discharged from the battery cooler 7 is transferred to the second evaporator 17, where it absorbs heat and evaporates to become high-dryness low-pressure gaseous refrigerant. After passing through the gas-liquid separator 13, it enters the second compressor 14 to complete a cycle. Among them, in the battery cooler 7, the low-temperature, low-pressure and low-dryness refrigerant evaporates and absorbs heat, reducing the temperature of the coolant at the battery end. The low-temperature water then enters the battery through the battery water circuit to achieve the purpose of cooling the battery.

[0059] (2) Passenger cabin refrigeration cycle: The second compressor 14 discharges high-temperature and high-pressure gaseous refrigerant, which passes through the internal condenser 15 and the first cut-off valve 18 in the air conditioning box and enters the external condenser 16 to become high-pressure liquid refrigerant. After throttling by the fourth throttling mechanism 24, it becomes low-temperature and low-pressure two-phase refrigerant and directly enters the second evaporator 17 in the air conditioning box without passing through the battery cooler 7. It evaporates and absorbs heat for cooling, and at the same time becomes high-dryness low-pressure gaseous refrigerant. After passing through the gas-liquid separator 13, it enters the second compressor 14 to complete a cycle.

[0060] (3) Heat pump heating cycle: Open the second shut-off valve 22, close the first shut-off valve 18, the fourth throttling mechanism 24 and the third throttling mechanism 23. The high-temperature and high-pressure gaseous refrigerant at the outlet of the second compressor 14 becomes a high-pressure liquid refrigerant after passing through the internal condenser 15 in the air conditioner box, is throttled by the second throttling mechanism 19 to become a low-temperature and low-pressure two-phase refrigerant, enters the external condenser 16. The external condenser 16 serves as a heat exchanger, evaporates and absorbs heat to become a high-dryness low-pressure gaseous refrigerant, and then enters the second compressor 14 through the gas-liquid separator 13 to complete a cycle.

[0061] The working principle of the present invention is as follows:

[0062] It is mainly divided into four circulation units. The first circulation unit 1 is used for refrigerating or heating the working medium in the second circulation unit. The fourth circulation unit is used for refrigerating or heating the working medium in the third circulation unit. The third circulation unit is for cooling the power battery. The circulation path is composed of the second water pump 8, the power battery circuit 10, the heat exchange device 9 and the battery cooler 7. The second circulation unit is for cooling the charging gun and the charging cable. The circulation path is composed of the first evaporator 104, the radiator 3, the first water pump 5 and the charging gun water circuit 6. Finally, the energy exchange of the working medium between the third circulation unit and the second circulation unit is realized through the quick connector and the heat exchange device 9.

[0063] Among them, as Figures 2 - 6 shown, the dotted lines in the figure represent the positions where there is no medium flow, and the solid lines represent the positions where there is medium flow. It can be divided into multiple modes according to the operating conditions. The following several modes are exemplified, and their principles are as follows:

[0064] 1. As Figure 2 shown, in cooling mode 1, for the case where the ambient temperature is relatively low, without the intervention of the fourth circulation unit and the first circulation unit 1 in the charging station, the temperature is completely dissipated through the radiator 3.

[0065] 2. As Figure 3 shown, in cooling mode 2, for the case where the ambient temperature is relatively high or the heat dissipation of the electric vehicle is relatively large, without the intervention of the fourth circulation unit, but the intervention of the first circulation unit 1 in the charging station is required, and the temperature is dissipated by the first circulation unit 1.

[0066] 3. As Figure 4 shown, in cooling mode 3, for the case where the ambient temperature is high or the cooling demand of the electric vehicle is large, the simultaneous intervention of the fourth circulation unit and the first circulation unit 1 is required.

[0067] 4. As Figure 5 shown, in heating mode 1, for the case where the ambient temperature is relatively low and heating is required but the temperature demand is not high, the medium is actively heated by the heater 4 for heat conduction.

[0068] 5. AsFigure 6 As shown, in heating mode 2, for the case where the ambient temperature is very low, heat conduction is performed through the combined active heating of heater 4 and PTC heater 12.

[0069] In the description of this specification, the description referring to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0070] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not elaborate on all details and do not limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A thermal management system for a coupled fast charging station and a vehicle, characterized in that: It includes a vehicle thermal management system, a charging station thermal management system, and a heat exchange device (9), and the heat exchange device (9) is arranged on the vehicle; The charging station thermal management system includes a first circulation unit (1) and a second circulation unit; The first circulation unit (1) is composed of a first compressor (101), a condenser (102), a first throttling mechanism (103), and a first evaporator (104) that are connected in sequence to form a first coolant / heat carrier medium circulation loop; The second circulation unit includes a pipeline connector (2), a radiator (3), a heater (4), a first water pump (5), and a charging gun water circuit (6); The outlet end of the first water pump (5) and the second coolant / heat carrier medium inlet end of the first evaporator (104) are both connected to a main pipe (105), and the pipeline connector (2), the radiator (3), and the heater (4) are connected in parallel between the two main pipes (105) in sequence; The charging gun water circuit (6) includes an inflow pipeline (601) and a return pipeline (602). The inlet of the inflow pipeline (601) is connected to the second coolant / heat carrier medium outlet end of the first evaporator (104), and the outlet of the return pipeline (602) is connected to the inlet of the first water pump (5); The outlet of the inflow pipeline (601) and the inlet of the return pipeline (602) are respectively connected to a group of connecting pipes (25) through quick connectors. The two connecting pipes (25) are respectively connected to the inlet and outlet of the first coolant / heat carrier medium of the heat exchange device (9), and the connection points of the connecting pipes (25) and the quick connectors are arranged at the position of the vehicle charging port; The vehicle thermal management system includes a third circulation unit and a fourth circulation unit; The third circulation unit includes a battery cooler (7), a second water pump (8), and a power battery circuit (10); The power battery circuit (10), the second coolant / heat carrier medium circulation loop of the heat exchange device (9), the first coolant / heat carrier medium circulation loop of the battery cooler (7), and the second water pump (8) are connected in sequence to form a circulation loop, and the second coolant / heat carrier medium circulation loop of the battery cooler (7) is connected to the fourth circulation unit; A connecting pipe (11) is provided on the pipeline between the heat exchange device (9) and the battery cooler (7) through a third three-way valve (26). The other end of the connecting pipe (11) is connected between the second water pump (8) and the battery cooler (7), and a PTC heater (12) is provided on the connecting pipe (11); The fourth cycle unit includes a gas-liquid separator (13), a second compressor (14), an internal condenser (15), a parallel pipe, an external condenser (16) and a second evaporator (17) which are connected in sequence to form a cycle loop. A first stop valve (18) and a second throttling mechanism (19) are respectively arranged on two pipe bodies of the parallel pipe. A first external connecting pipe (20) is arranged on the pipeline between the external condenser (16) and the second evaporator (17). The other end of the first external connecting pipe (20) is connected to the inlet end of the second heat transfer medium of the battery cooler (7). The outlet end of the second heat transfer medium of the battery cooler (7) is connected to the pipeline between the second evaporator (17) and the gas-liquid separator (13); A first three-way valve (106) is arranged between the main pipe (105) on the heater (4), the radiator (3) and the first water pump (5). The pipeline connector (2) is connected to the main pipe (105) and the connection point is located between the first three-way valve (106) and the first water pump (5); A second three-way valve (107) is connected to the main pipe (105) between the first evaporator (104) and the heater (4). The end of the pipeline connector (2) is connected to the other interface of the second three-way valve (107).

2. The thermal management system of a coupled fast charging station and a whole vehicle according to claim 1, characterized in that A second external connecting pipe (21) is connected to the pipeline between the external condenser (16) and the battery cooler (7). The other end of the second external connecting pipe (21) is connected to the pipeline between the gas-liquid separator (13) and the second evaporator (17). A second stop valve (22) is arranged on the second external connecting pipe (21).

3. The thermal management system of a coupled fast charging station and a whole vehicle according to claim 2, characterized in that, A third throttling mechanism (23) is arranged on the first external connecting pipe (20). A fourth throttling mechanism (24) is arranged on the pipeline between the external condenser (16) and the second evaporator (17). The fourth throttling mechanism (24) is located at the rear position of the first external connecting pipe (20).

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