Air supply system and vehicle

Abstract

The utility model relates to an air supply system and a vehicle, and the air supply system comprises a feeding pipeline which is used for connecting a cathode feeding end of a galvanic pile; the discharging pipeline is used for being connected with a cathode discharging end of the electric pile; the air compressor is provided with a compression end arranged on the feeding pipeline and an expansion end arranged on the discharging pipeline; and the heat exchanger is connected to the feeding pipeline and the discharging pipeline, can exchange heat of the feeding pipeline and the discharging pipeline, and is positioned at the downstream of the compression end and the upstream of the expansion end. The heat exchangers are connected to the feeding pipeline and the discharging pipeline of the stack cathode to exchange heat of the two pipelines, so that the temperature of the feeding pipeline can be reduced by effectively utilizing the temperature difference of the two pipelines, the heat dissipation requirement of the system is reduced while the energy utilization efficiency is improved, and the gas temperature at the inlet of the expansion end is effectively improved; therefore, the service life of the expansion end is prolonged, energy recovery at the expansion end is facilitated, and the overall energy utilization efficiency of the system is further improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of fuel cells, and more particularly, to an air supply system and a vehicle. Background Art

[0002] For the cathode in a high-power vehicle fuel cell system, under normal operating conditions, the conditions to be met include a large air flow rate and a high pressure ratio. However, the high pressure ratio causes the temperature of the air to rise significantly after passing through the air compressor. Coupled with the large flow rate and high temperature rise, the heat dissipation requirement for the air increases before entering the fuel cell stack. For a high-power fuel cell system, the heat dissipation requirement of the fuel cell stack itself is already very large. Coupled with the heat dissipation of the supplied air, a larger radiator and a cooling fan with a higher air volume are required, increasing the difficulty of the vehicle design. In addition, the heat generated by the air compressor pressurizing the air is not utilized, reducing the energy utilization efficiency of the entire fuel cell system. Summary of the Utility Model

[0003] The purpose of the present disclosure is to provide an air supply system and a vehicle to reduce the heat dissipation requirement at the cathode inlet end of the fuel cell stack, and at the same time enable energy recovery at the expansion end of the air compressor at the cathode outlet end of the fuel cell stack, improving the energy utilization efficiency of the system.

[0004] To achieve the above purpose, the present disclosure provides an air supply system, including:

[0005] A feed pipeline for connecting the cathode feed end of the fuel cell stack;

[0006] A discharge pipeline for connecting the cathode discharge end of the fuel cell stack;

[0007] An air compressor having a compression end disposed on the feed pipeline and an expansion end disposed on the discharge pipeline; and

[0008] A heat exchanger connected to the feed pipeline and the discharge pipeline, capable of exchanging heat between the feed pipeline and the discharge pipeline, and the heat exchanger is located downstream of the compression end and upstream of the expansion end.

[0009] Optionally, the air supply system further includes:

[0010] An intercooler connected to the feed pipeline and located downstream of the heat exchanger for adjusting the temperature of the gas in the feed pipeline; and

[0011] A humidifier connected at least to the feed pipeline and located downstream of the intercooler for at least adjusting the humidity of the gas in the feed pipeline.

[0012] Optionally, the air supply system further includes a first control valve, which is disposed on the feed pipeline and upstream of the intercooler.

[0013] Optionally, the intercooler and the humidifier are integrally arranged.

[0014] Optionally, the humidifier is further connected to the discharge pipeline and can allow the water vapor in the discharge pipeline to enter the feed pipeline.

[0015] Optionally, a steam separator is further connected to the discharge pipeline and is upstream of the heat exchanger.

[0016] Optionally, the air supply system further includes a second control valve, which is connected to the discharge pipeline and upstream of the steam separator.

[0017] Optionally, the air supply system further includes a first branch bypassing the feed pipeline, with both ends of the first branch connected to both sides of the heat exchanger respectively. The air supply system further includes a third control valve, which is disposed on the first branch and used to control the flow rates of the first branch and the feed pipeline.

[0018] Optionally, the air supply system further includes a second branch bypassing the discharge pipeline, with both ends of the second branch connected to both sides of the heat exchanger respectively. The air supply system further includes a fourth control valve, which is disposed on the second branch and used to control the flow rates of the second branch and the discharge pipeline.

[0019] According to another aspect of the present disclosure, a vehicle is provided, including a fuel cell stack and the above-mentioned air supply system.

[0020] Through the above technical solution, a heat exchanger is connected to the feed pipeline and the discharge pipeline on the cathode side of the fuel cell stack to exchange the heat of the two pipelines. The temperature difference between the two pipelines can be effectively utilized to reduce the temperature of the feed pipeline, improve the energy utilization efficiency, and reduce the system heat dissipation requirement at the same time. Since the temperature of the discharge pipeline increases after heat exchange, the gas temperature at the inlet of the expansion end can also be effectively increased, reducing the content of liquid water in the gas entering the expansion end, thereby prolonging the life of the expansion end and facilitating the energy recovery at the expansion end, further improving the overall energy utilization efficiency of the system.

[0021] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation part. Description of the Drawings

[0022] The accompanying drawings are used to provide a further understanding of the present disclosure and form a part of the specification. Together with the following detailed description, they are used to explain the present disclosure, but do not limit the present disclosure. In the accompanying drawings:

[0023] Figure 1 is a schematic diagram of an air supply system according to an embodiment of the present disclosure.

[0024] Figure 2 is a schematic diagram of an air supply system according to another embodiment of the present disclosure.

[0025] Description of Reference Numerals

[0026] 1 - fuel cell stack; 11 - feed pipeline; 12 - discharge pipeline; 13 - first branch; 14 - second branch; 21 - compression end; 22 - expansion end; 3 - heat exchanger; 41 - intercooler; 42 - humidifier; 51 - first control valve; 52 - second control valve; 53 - third control valve; 54 - fourth control valve; 6 - steam separator; 7 - air filter; 8 - cooling subsystem. Detailed Description of the Embodiment

[0027] The following is a detailed description of the specific embodiments of the present disclosure in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining and understanding the present disclosure, and do not limit the present disclosure.

[0028] In the present disclosure, unless otherwise stated, the directional terms such as "upstream" and "downstream" are defined according to the actual air flow direction sequence of the air supply system. The specific air flow direction in the air supply system can be specifically referred to Figure 1 and Figure 2 the directions indicated by the arrows in, and the terms such as "first" and "second" are used to distinguish different components, and do not have a sequential or important meaning. In addition, in the following description, when referring to the accompanying drawings, unless otherwise explained, the same reference numerals in different drawings represent the same or similar elements.

[0029] According to an embodiment of the present disclosure, as shown in Figure 1 and Figure 2As shown in the figure, an air supply system is provided, which may include a feed pipeline 11, a discharge pipeline 12, an air compressor, and a heat exchanger 3. Among them, the feed pipeline 11 is used to connect the cathode feed end of the fuel cell stack 1. Here, the fuel cell stack 1 may refer to a battery stack formed by stacking multiple fuel cell monomers. The discharge pipeline 12 is used to connect the cathode discharge end of the fuel cell stack 1. The air compressor has a compression end 21 disposed on the feed pipeline 11 and an expansion end 22 disposed on the discharge pipeline 12. The heat exchanger 3 is connected between the feed pipeline 11 and the discharge pipeline 12, capable of exchanging heat between the feed pipeline 11 and the discharge pipeline 12, and the heat exchanger 3 is located downstream of the compression end 21 and upstream of the expansion end 22. Here, the compression end 21 can increase the temperature and pressure of the gas before entering the fuel cell stack 1 to improve the power density and efficiency of the fuel cell stack 1. The expansion end 22 has a turbine, and the turbine is coaxially connected to the motor of the compression end 21. The function of the expansion end 22 is to recover energy. When the gas from the outlet side of the fuel cell stack 1 is diverted to the expansion end 22, it can drive the turbine in the expansion end 22 to rotate, thereby adding additional torque to the motor rotor of the coaxially connected compression end 21 to assist in driving the compression end 21 to compress the gas, thus reducing the output power of the motor of the compression end 21 of the air compressor, reducing the cost of compressing the gas by the compression end 21 of the air compressor, and improving the efficiency of the entire air compressor.

[0030] Through the above technical solution, a heat exchanger 3 is connected to the feed pipeline 11 and the discharge pipeline 12 on the cathode side of the fuel cell stack 1 to exchange heat between the two pipelines, which can effectively utilize the temperature difference between the two pipelines themselves to reduce the temperature of the feed pipeline 11, improve the energy utilization efficiency while reducing the system heat dissipation requirement. Since the temperature of the discharge pipeline 12 increases after heat exchange, it can also effectively increase the temperature of the gas at the inlet of the expansion end 22, reduce the content of liquid water in the gas entering the expansion end 22, thereby extending the life of the expansion end 22, and also facilitating energy recovery at the expansion end 22, further improving the overall energy utilization efficiency of the system.

[0031] It should be noted that the above are the effects under normal operating conditions. In normal operating conditions, since the compression end 21 will increase the temperature and pressure of the gas, the gas temperature at the outlet of the compression end 21 is higher than the gas temperature requirement at the inlet of the fuel cell stack 1. Therefore, cooling is required. Although heat energy will be generated after the gas reacts in the fuel cell stack 1, the gas at the outlet of the compression end 21 is cooled before entering the fuel cell stack 1. Therefore, the gas temperature discharged from the fuel cell stack 1 will still be lower than the gas temperature at the outlet of the compression end 21. At this time, during heat exchange in the heat exchanger 3, the gas in the feed pipeline 11 of the heat exchanger 3 is cooled, while the gas in the discharge pipeline 12 is heated. In special operating conditions such as startup, idle point, and low-power operating point, the gas temperature passing through the compression end 21 will be lower than the gas temperature requirement at the inlet of the fuel cell stack 1. At this time, it is necessary to heat the gas in the feed pipeline 11. The heat energy generated by the fuel cell stack 1 can be utilized, and through the heat exchange of the heat exchanger 3, the gas at the inlet of the expansion end 22 heats the gas at the outlet of the compression end 21, so that the gas in the feed pipeline 11 of the heat exchanger 3 is heated, and the gas in the discharge pipeline 12 is cooled, reducing the heating requirement of the subsequent intercooler 41 for the gas in the feed pipeline 11.

[0032] In addition, an air filter 7 can also be connected to the position on the feed pipeline 11 upstream of the compression end 21 to filter the gas entering the feed pipeline 11 and prevent impurities in the gas from affecting the air compressor and affecting the service life of the air compressor.

[0033] Furthermore, as Figure 1 and Figure 2 shown, the air supply system further includes an intercooler 41 and a humidifier 42. The intercooler 41 can be connected to the feed pipeline 11 and is located downstream of the heat exchanger 3 for adjusting the temperature of the gas in the feed pipeline 11. The humidifier 42 can be at least connected to the feed pipeline 11 and is located downstream of the intercooler 41, at least for adjusting the humidity of the gas in the feed pipeline 11. The function of the intercooler 41 is to further cool the feed pipeline 11. Among them, the intercooler 41 can be connected to an external cooling subsystem 8 to cool the feed pipeline 11. The intercooler 41 is arranged at the downstream end of the heat exchanger 3 in the feed pipeline 11. After the feed pipeline 11 has been cooled by the heat exchanger 3, the working pressure of the intercooler 41 can also be effectively reduced. The function of the humidifier 42 is to increase the humidity of the gas entering the fuel cell stack 1 to reduce the impact on the proton exchange membrane in the fuel cell stack 1 and improve the service life of the proton exchange membrane.

[0034] Furthermore, as Figure 1 and Figure 2As shown, the air supply system may further include a first control valve 51. The first control valve 51 is disposed on the feed pipeline 11 and is located upstream of the intercooler 41. Since the temperature of the feed pipeline 11 decreases after heat exchange with the discharge pipeline 12 through the heat exchanger 3, and the temperature range of the heat-exchanged feed pipeline 11 meets the operating temperature of the first control valve 51, the first control valve 51 can be disposed at the upstream end of the intercooler 41. In this way, the flow rate of the gas can be controlled by controlling the opening degree of the first control valve 51, so that the gas can enter the intercooler 41 for more precise adjustment. Here, since the first control valve 51 is disposed at the upstream end of the intercooler 41, the intercooler 41 can be directly connected to the humidifier 42, that is, the intercooler 41 and the humidifier 42 can be integrally arranged without installing other components between them. For example, the intercooler 41 and the humidifier 42 can be welded on the same base and connected. In this way, when the air supply system is installed, they can be installed as a whole at one time. Since there are no additional components between the intercooler 41 and the humidifier 42, this installation can also reduce the connecting pipeline between the intercooler 41 and the humidifier 42, reducing the complexity of the system design. At the same time, since the connecting pipeline between them becomes shorter, the flow resistance between the intercooler 41 and the humidifier 42 can be reduced, thereby reducing the energy consumption caused by the flow resistance and improving the efficiency of the air supply system.

[0035] According to an embodiment of the present disclosure, as Figure 1 and Figure 2 shown, the humidifier 42 may also be connected to the discharge pipeline 12, that is, one humidifier 42 is connected to both the feed pipeline 11 and the discharge pipeline 12 at the same time, enabling the water vapor in the discharge pipeline 12 to enter the feed pipeline 11. It can not only effectively utilize the water generated in the fuel cell stack 1 to humidify the gas before entering the fuel cell stack 1, but also reduce the liquid water content in the gas in the discharge pipeline 12 flowing out of the humidifier 42, thereby reducing the liquid water content in the gas entering the expansion end 22 and reducing the impact on the impeller in the expansion end 22, improving the service life of the expansion end 22.

[0036] According to an embodiment of the present disclosure, as Figure 1 and Figure 2 shown, a steam-water separator 6 is further connected to the discharge pipeline 12. The steam-water separator 6 is located upstream of the heat exchanger 3 to reduce the liquid water content in the gas in the discharge pipeline 12 flowing out of the steam-water separator 6, thereby reducing the liquid water content in the gas entering the expansion end 22 and reducing the impact on the impeller in the expansion end 22, improving the service life of the expansion end 22.

[0037] Furthermore, as Figure 1 and Figure 2As shown, the air supply system may further include a second control valve 52. The second control valve 52 is connected to the discharge pipeline 12 and is located upstream of the steam-water separator 6. In this way, the gas flow rate can be controlled by controlling the opening degree of the second control valve 52 according to the content of liquid water in the gas, so that the gas can enter the steam-water separator 6 for more precise gas-liquid separation, reducing the energy consumption while ensuring the gas-liquid separation effect and reducing the cost. Here, the first control valve 51, the second control valve 52, the intercooler 41 and the humidifier 42 can be integrated. That is, the first control valve 51 can be connected to the inlet of the intercooler 41, and the second control valve 52 can be connected to the outlet of the humidifier 42 on the discharge pipeline 12, reducing the system design difficulty.

[0038] According to an embodiment of the present disclosure, as Figure 2 shown, the air supply system may further include a first branch 13 bypassing the feed pipeline 11 and a second branch 14 bypassing the discharge pipeline 12. Both ends of the first branch 13 are respectively connected to both sides of the heat exchanger 3. The air supply system further includes a third control valve 53, and the third control valve 53 can control the flow rates of the first branch 13 and the feed pipeline 11. Both ends of the second branch 14 are respectively connected to both sides of the heat exchanger 3. The air supply system further includes a fourth control valve 54, and the fourth control valve 54 can control the flow rates of the second branch 14 and the discharge pipeline 12. To adjust the gas flow rate entering the heat exchanger 3 corresponding to the temperatures of the feed pipeline 11 and the discharge pipeline 12. When the temperature of the feed pipeline 11 is relatively low, at this time the heat dissipation requirement of the air supply system is relatively low. To reduce the energy consumption of the heat exchanger 3, it is not necessary for all the gas flowing through the feed pipeline 11 and the discharge pipeline 12 to enter the heat exchanger 3. Therefore, at this time, the flow rates of the first branch 13 and the second branch 14 can be increased respectively through the third control valve 53 and the fourth control valve 54, and the flow rates of the feed pipeline 11 and the discharge pipeline 12 entering the heat exchanger 3 can be reduced. The flow rates of different routes can be adjusted according to the actual heat dissipation requirement. When the temperature of the feed pipeline 11 is lower, the higher the gas flow rate entering the first branch 13 controlled by the third control valve 53. When the temperature of the feed pipeline 11 is higher, the lower the gas flow rate entering the first branch 13 controlled by the third control valve 53. When the temperature of the discharge pipeline 12 is lower, the lower the gas flow rate entering the second branch 14 controlled by the fourth control valve 54. When the temperature of the discharge pipeline 12 is higher, the higher the gas flow rate entering the second branch 14 controlled by the fourth control valve 54.

[0039] Here, regarding the setting modes of the third control valve 53 and the fourth control valve 54, both the third control valve 53 and the fourth control valve 54 can be three-way valves. The three-way valves can be correspondingly connected to the connection point between the first branch 13 and the feed pipeline 11, and the connection point between the second branch 14 and the discharge pipeline 12, and the flow rates of the four pipelines can be correspondingly controlled by controlling the three-way valves. The third control valve 53 and the fourth control valve 54 can also be regulating valves that can control the opening degree. Among them, the third control valve 53 can be arranged on the first branch 13, and the fourth control valve 54 can be arranged on the second branch 14. When it is necessary to increase the flow rates of the first branch 13 and the second branch 14, the opening degrees of the third control valve 53 and the fourth control valve 54 can be increased, so that the flow rates of the first branch 13 and the second branch 14 increase, and correspondingly, the flow rates of the feed pipeline 11 and the discharge pipeline 12 entering the heat exchanger 3 decrease. When it is necessary to decrease the flow rates of the first branch 13 and the second branch 14, the opening degrees of the third control valve 53 and the fourth control valve 54 can be decreased, so that the flow rates of the first branch 13 and the second branch 14 decrease, and correspondingly, the flow rates of the feed pipeline 11 and the discharge pipeline 12 entering the heat exchanger 3 increase.

[0040] It is also possible that the third control valve 53 is arranged on the feed pipeline 11, the setting position is at the inlet of the heat exchanger 3, and downstream of the connection end of the feed pipeline 11 and the first branch 13, and the fourth control valve 54 is arranged on the discharge pipeline 12, the setting position is at the inlet of the heat exchanger 3, and downstream of the connection end of the discharge pipeline 12 and the second branch 14. When it is necessary to increase the flow rates of the first branch 13 and the second branch 14, the opening degrees of the third control valve 53 and the fourth control valve 54 can be decreased, so that the flow rates of the first branch 13 and the second branch 14 increase, and correspondingly, the flow rates of the feed pipeline 11 and the discharge pipeline 12 entering the heat exchanger 3 decrease. When it is necessary to decrease the flow rates of the first branch 13 and the second branch 14, the opening degrees of the third control valve 53 and the fourth control valve 54 can be increased, so that the flow rates of the first branch 13 and the second branch 14 decrease, and correspondingly, the flow rates of the feed pipeline 11 and the discharge pipeline 12 entering the heat exchanger 3 increase.

[0041] On the basis of the above solutions, the present disclosure also provides a vehicle, which includes a fuel cell stack 1 and the above air supply system, and this vehicle has all the beneficial effects of the above air supply system, which will not be elaborated here.

[0042] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0043] In addition, it should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without conflict. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combinations.

[0044] Furthermore, any combination can be made among the various different embodiments of the present disclosure, as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.

Claims

1. An air supply system, characterized in that: include: A feed pipeline, used to connect the cathode feed end of the fuel cell stack; A discharge pipeline, used for connecting to the cathode discharge terminal of the battery stack; an air compressor having a compression end disposed on the feed pipeline and an expansion end disposed on the discharge pipeline; and A heat exchanger is connected to the feed pipeline and the discharge pipeline, capable of exchanging heat between the feed pipeline and the discharge pipeline, and the heat exchanger is located downstream of the compression end and upstream of the expansion end.

2. The air supply system according to claim 1, characterized in that: The air supply system further comprises: an intercooler connected to the feed pipeline and located downstream of the heat exchanger, for adjusting the temperature of the gas in the feed pipeline; and A humidifier, the humidifier is at least connected to the feed pipeline and is located downstream of the intercooler, and is at least used to adjust the humidity of the gas in the feed pipeline.

3. The air supply system according to claim 2, characterized in that: The air supply system further includes a first control valve, which is disposed on the feed line and is located upstream of the intercooler.

4. The air supply system according to claim 3, characterized in that: The intercooler and the humidifier are integrated.

5. The air supply system according to claim 2, characterized in that: The humidifier is also connected to the discharge pipeline and can allow the water vapor in the discharge pipeline to enter the feed pipeline.

6. The air supply system according to claim 1, characterized in that: The discharge pipeline is also connected with a steam-water separator, and the steam-water separator is located upstream of the heat exchanger.

7. The air supply system according to claim 6, characterized in that The air supply system further comprises a second control valve, which is connected to the discharge pipeline and is located upstream of the steam-water separator.

8. The air supply system according to claim 1, characterized in that: The air supply system also includes a first branch bypassing the feed pipeline, wherein both ends of the first branch are respectively connected to both sides of the heat exchanger. The air supply system also includes a third control valve, which is arranged on the first branch and is used to control the flow of the first branch and the feed pipeline.

9. The air supply system according to claim 1, characterized in that: The air supply system also includes a second branch connected to the discharge pipeline, and the two ends of the second branch are respectively connected to the two sides of the heat exchanger. The air supply system also includes a fourth control valve, which is arranged on the second branch and is used to control the flow of the second branch and the discharge pipeline.

10. A vehicle, characterized in that: It comprises a fuel cell stack and the air supply system according to any one of claims 1 to 9.

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