Shutdown control method, fuel cell system and vehicle

Abstract

The invention discloses a shutdown control method, a fuel cell system and a vehicle, the shutdown control method is used for the fuel cell system, the fuel cell system comprises an electric pile cavity purging air inlet pipeline, an electric pile cavity purging discharge pipeline and a drainage pipe, a purging branch is arranged between a purging exhaust pipeline of the galvanic pile cavity and a drainage pipe, a purging control valve is arranged on the purging branch, and the shutdown control method comprises the following steps: in response to the completion of drainage of a drainage valve, controlling the purging control valve to be opened, and controlling the purging control valve to be closed; gas in the discharge pipeline is purged through the electric pile cavity so as to purge the drainage pipe; recording the time for purging the drainage pipe; and when the time for purging the drainage pipe reaches first preset time, the purging control valve is controlled to be closed. According to the control method, the residual hydrogen in the drain pipe can be effectively treated, and the residual hydrogen is prevented from diffusing into the galvanic pile shell, so that the safety of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a shutdown control method, a fuel cell system and a vehicle. Background Art

[0002] In the related art, fuel cells generate electricity through the reaction of hydrogen and oxygen, and the water generated on the cathode side needs to diffuse across the proton exchange membrane to the anode side (hydrogen side). However, after a long period of operation, too much water may accumulate on the anode side of the fuel cell system, resulting in blockage of the hydrogen flow channel, which in turn affects the supply of hydrogen and reduces the output power and life of the fuel cell. Therefore, it is necessary to regularly drain the anode side of the fuel cell system. During the drainage process, part of the hydrogen will be discharged along with the water, merged into the tail gas and discharged into the atmosphere.

[0003] However, after the fuel cell system is shut down, hydrogen often remains in the drainage pipeline, and this residual hydrogen may diffuse into the stack shell through the tail drain and stack shell purge pipeline. This may cause the hydrogen concentration in the stack shell to increase, and when the fuel cell is started again, the hydrogen concentration sensor in the stack shell may detect a high concentration of hydrogen and trigger an alarm. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide a shutdown control method, which can effectively deal with the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the battery stack shell, thereby improving the safety of the system and ensuring the normal operation of the battery.

[0005] A second object of the present invention is to provide a fuel cell system.

[0006] A third object of the present invention is to provide a vehicle.

[0007] In order to achieve the above-mentioned purpose, a shutdown control method of an embodiment of the first aspect of the present invention is used for a fuel cell system, wherein the fuel cell system includes a stack cavity purge inlet pipeline and a stack cavity purge exhaust pipeline and a drain pipe for purging the stack, a purge branch is arranged between the stack cavity purge exhaust pipeline and the drain pipe, and a purge control valve is arranged on the purge branch, and the shutdown control method includes: in response to the completion of drainage of the stack, controlling the purge control valve to open so as to purge the drain pipe with the gas in the stack cavity purge exhaust pipeline; recording the time for purging the drain pipe; when the time for purging the drain pipe reaches a first preset time, controlling the purge control valve to close.

[0008] According to the shutdown control method of an embodiment of the present invention, a purge branch and a purge control valve are set between the stack cavity purge exhaust pipeline and the drain pipe. After the system is drained, the purge control valve is controlled to open, and the drain pipe is forcibly purged by the gas in the stack cavity purge exhaust pipeline. When the purge time for the drain pipe reaches a first preset time, the purge control valve is controlled to close. This process can effectively deal with the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate in the system when it is shut down, thereby improving the safety of the fuel cell system and ensuring the normal operation of the battery.

[0009] In some embodiments, the fuel cell system further includes an air compressor for providing purge gas to the stack cavity purge air intake line, and the shutdown control method further includes: after controlling the purge control valve to close, controlling the air compressor to delay closing for a second preset time.

[0010] In some embodiments, the shutdown control method further includes: in response to a shutdown instruction, controlling the anode intake valve of the fuel cell system to close, and controlling the air compressor to continue running to continue to purge the fuel cell stack through the stack cavity purge intake line.

[0011] In some embodiments, the shutdown control method further includes: controlling the drain valve of the fuel cell to open to drain water through the drain pipe; recording the time for the drain pipe to drain water; and determining that the drain valve has finished draining water when the drain pipe drainage time reaches a third preset time.

[0012] In order to achieve the above-mentioned purpose, the fuel cell system of the second embodiment of the present invention includes: a fuel cell stack, which includes a shell and a core; a fuel cell stack cavity purge inlet pipeline, which is connected to the shell and is used to introduce air into the shell to purge the gap between the shell and the core; a fuel cell stack cavity purge exhaust pipeline, which is connected to the shell and is used to discharge the exhaust gas in the gap; a drain pipe, which is connected to the shell and is used to discharge the waste water generated by the fuel cell; a purge branch, which is arranged between the fuel cell stack cavity purge exhaust pipeline and the drain pipe; a purge control valve, which is arranged on the purge branch to control the on-off of the purge branch; and a controller, which is used to execute the shutdown control method described in the above embodiment.

[0013] According to the fuel cell system of an embodiment of the present invention, after discharging the waste water generated by the fuel cell, the controller executes the shutdown control method described in the above embodiment, and controls the purge control valve to open, and the stack cavity purge discharge pipeline injects air into the drain pipe through the purge branch to realize forced purge of the drain pipe, thereby effectively treating the residual hydrogen in the drain pipe and preventing the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate in the system when it is shut down, thereby improving the safety of the fuel cell system and ensuring the normal operation of the battery.

[0014] In some embodiments, the fuel cell system further includes: a hydrogen storage container, the gas outlet of which is connected to the shell to allow hydrogen to be introduced into the shell; and a hydrogen inlet valve, which is disposed on a pipeline between the hydrogen storage container and the shell to control the hydrogen introduced into the shell.

[0015] In some embodiments, the fuel cell system further includes: a gas-liquid separator, wherein the inlet of the gas-liquid separator is connected to the shell, the gas outlet of the gas-liquid separator is connected to the pipeline between the hydrogen storage container and the shell, and the liquid outlet of the gas-liquid separator is connected to the drain pipe; and a drain valve, wherein the drain valve is arranged at the liquid outlet of the gas-liquid separator.

[0016] In some embodiments, the fuel cell system also includes: an air compressor; an intercooler, wherein the input port of the intercooler is connected to the exhaust port of the air compressor, and the output port of the intercooler is connected to the stack cavity purge inlet pipeline; a humidifier, wherein the first input port of the humidifier is connected to the output port of the intercooler, and the first output port of the humidifier is connected to the shell through an intake pipe to introduce air into the shell, and the second input port of the humidifier is connected to the shell through a first exhaust pipe to discharge exhaust gas in the shell; and a main exhaust pipe, wherein the main exhaust pipe is respectively connected to the second output port of the humidifier, the stack cavity purge exhaust pipeline, and the drain pipe.

[0017] In some embodiments, the fuel cell system further includes: a bypass line connected between the output port of the intercooler and the main exhaust pipe; and a bypass valve disposed on the bypass line.

[0018] In order to achieve the above-mentioned object, a vehicle according to an embodiment of the third aspect of the present invention comprises the fuel cell system described in the above embodiment.

[0019] According to the vehicle of the embodiment of the present invention, by adopting the fuel cell system described in the above embodiment, after discharging the waste water generated by the fuel cell, the purge control valve is controlled to open, and the stack cavity purge discharge pipeline flows air into the drain pipe through the purge branch to realize forced purge of the drain pipe, thereby effectively treating the residual hydrogen in the drain pipe and preventing the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate when the system is in the shutdown state, thereby improving the safety of the fuel cell system and ensuring the normal operation of the battery.

[0020] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 is a schematic diagram of a fuel cell system according to one embodiment of the present invention;

[0023] Figure 2 is a flow chart of a shutdown control method according to an embodiment of the present invention;

[0024] Figure 3 is a flowchart of system shutdown purge according to one embodiment of the present invention;

[0025] Figure 4 is a block diagram of a vehicle according to one embodiment of the present invention.

[0026] Reference numerals:

[0027] Vehicle 100;

[0028] Fuel cell system 101;

[0029] Fuel cell 1; Fuel cell cavity purge inlet pipeline 2; Fuel cell cavity purge outlet pipeline 3; Drain pipe 4; Purge branch 5; Hydrogen storage container 6; Hydrogen inlet valve 7; Gas-liquid separator 8;

[0030] air compressor 10 ; intercooler 20 ; humidifier 30 ; main exhaust pipe 40 ; intake pipe 50 ; bypass pipe 60 ; first exhaust pipe 70 ; hydrogen concentration sensor 11 ; drain valve 41 ; purge control valve 51 ; bypass valve 61 . DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0032] In response to the problem in the related art that after the fuel cell system is shut down, hydrogen often remains in the drain pipe, and the residual hydrogen may diffuse into the interior of the fuel cell stack shell through the tail exhaust and the fuel cell stack shell purge pipe, an embodiment of the present invention proposes a shutdown control method. The shutdown control method of the embodiment of the present invention can effectively deal with the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the fuel cell stack shell, thereby improving the safety of the system.

[0033] In order to facilitate the description of the technical solution, the fuel cell system according to an embodiment of the present invention will be described below.

[0034] Figure 1 is a schematic diagram of a fuel cell system according to an embodiment of the present invention. Figure 1 As shown, the fuel cell system 101 includes: a fuel cell stack 1, a fuel cell stack cavity purge inlet pipeline 2, a fuel cell stack cavity purge exhaust pipeline 3, a drain pipe 4, a purge branch 5, a purge control valve 51 and a controller.

[0035] Among them, the stack 1 can be the core component of the fuel cell system 101, including a shell and a core. The shell can be used to wrap and protect the core, maintain the isolation of the core from the external environment, and ensure the safe operation of the stack 1. In an embodiment, the shell of the stack 1 can be made of a variety of different materials, and the specific choice depends on the design, performance requirements and application environment of the fuel cell system 101. Common stack shell materials can include stainless steel, carbon fiber composite materials, polymers and metal coating materials.

[0036] Specifically, stainless steel is a commonly used stack housing material that is popular for its corrosion resistance, high strength and relatively low cost. Stainless steel is able to resist corrosion in humid environments and is relatively easy to process. Carbon fiber composites are also commonly used in stack housings, which are generally lighter while having excellent strength and stiffness. These materials are critical to reducing the overall weight of the stack 1 and improving performance. They are also resistant to corrosion, but may require additional protection in high temperature environments. Polymer materials such as polypropylene or polyethylene can also be used in stack housings. They are often used in low-temperature fuel cell systems because they have relatively low corrosion resistance and mechanical strength, but have low manufacturing costs. The stack housing can also be made of metal-coated materials that are resistant to high temperatures and corrosion, and this material is relatively more used in high-temperature fuel cell systems.

[0037] In some embodiments, the core is the part that reacts hydrogen and oxygen to generate electricity. The core can be a PEMFC (Proton Exchange Membrane Fuel Cell) core. This type of core can use a proton exchange membrane to separate the anode and cathode, as well as to separate hydrogen and oxygen. The core is usually composed of many unit cells, each of which can include an anode, a cathode and a proton exchange membrane. These unit cells are stacked together to form an electric stack 1. The material of the core can usually include a proton exchange membrane, a catalyst layer and a supporting layer. The proton exchange membrane is usually made of a fluorinated polymer and has high electrical conductivity and proton conductivity. The catalyst layer usually includes a precious metal catalyst, such as platinum. The supporting layer is usually made of carbon or carbon nanotubes for supporting the catalyst and providing electronic conductivity.

[0038] In some embodiments, the stack cavity purge air intake line 2 may refer to a line or channel in the fuel cell system 101. The stack cavity purge air intake line 2 is connected to the shell and is used to introduce air into the shell to purge the gap between the shell and the core to prevent hydrogen leaked from the stack 1 from accumulating in the shell and causing danger, which helps maintain a proper gas environment in the stack 1 to promote the electrochemical reaction. The stack cavity purge exhaust line 3 is also connected to the shell and is used to exhaust the exhaust gas in the gap to keep the internal environment of the stack 1 clean and ensure the normal operation of the stack 1.

[0039] In certain embodiments, the fuel cell generates electricity by reacting hydrogen and oxygen, and the water produced on the cathode side may diffuse to the anode side (hydrogen side) across the proton exchange membrane. Too much water on the anode side may block the hydrogen flow channel, resulting in insufficient hydrogen supply, affecting the output power and life of the fuel cell. Therefore, it is necessary to regularly drain the anode side, and the drain pipe 4 can be the main channel for fuel cell system 101 to drain water, and the drain pipe 4 is connected to the housing for discharging the waste water produced by the fuel cell. Waste water generally comprises water and hydrogen.

[0040] In some embodiments, the purge branch 5 may refer to a pipeline or channel connecting the purge exhaust pipeline of the stack cavity and the drain pipe 4. The main function of the purge branch 5 may be to deal with the problem of residual hydrogen in the drain pipe 4 when the system is shut down, and to prevent the hydrogen from diffusing into the stack shell. The purge control valve 51 may be arranged on the purge branch 5 to control the on-off of the purge branch 5. Specifically, when the system is shut down, after the drain valve 41 is closed, the purge control valve 51 is controlled to open, and the residual hydrogen in the drain pipe 4 is forced to be purged by the purge air of the stack shell to remove the residual hydrogen in the drain pipe 4. In addition, when the fuel-electric system is running, the purge control valve 51 needs to be closed to prevent the hydrogen in the drain pipe 4 from entering the stack shell through the purge branch 5.

[0041] In some embodiments, the controller can be the intelligent control center of the entire system. It executes the shutdown control method described in the following embodiments. The controller is responsible for monitoring the status of the system, responding to corresponding signals, coordinating the operation of various components, and ensuring that the residual hydrogen in the drain pipe 4 is effectively processed. In addition, the controller can also record various parameters and execution time to facilitate monitoring and maintenance of system operation.

[0042] According to the fuel cell system 101 of an embodiment of the present invention, after discharging the waste water generated by the fuel cell, the controller executes the shutdown control method described in the following embodiment, and controls the purge control valve 51 to open, and the stack cavity purge discharge pipeline 3 flows air into the drain pipe 4 through the purge branch 5, so as to realize forced purge of the drain pipe 4, thereby effectively treating the residual hydrogen in the drain pipe 4 and preventing the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate in the system when it is shut down, thereby improving the safety of the fuel cell system 101 and ensuring the normal operation of the battery.

[0043] In some embodiments, the fuel cell system 101 further includes a hydrogen storage container 6 and a hydrogen inlet valve 7. The hydrogen storage container 6 may be a device for storing hydrogen, typically a gas pressure container. In the fuel cell system 101, the gas outlet of the hydrogen storage container 6 is connected to the shell, allowing hydrogen to be introduced into the shell. The function of the hydrogen storage container 6 may be to provide a hydrogen supply for use by the stack 1 during operation. It can store high-pressure hydrogen to ensure that the stack 1 can obtain sufficient hydrogen when needed to maintain the normal operation of the system. The hydrogen storage container 6 can be designed according to the needs of the system, and generally needs to have sufficient gas storage capacity to support the operation of the system, and needs to ensure the safe storage and release of hydrogen.

[0044] The hydrogen inlet valve 7 may be a control valve disposed on the pipeline between the hydrogen storage container 6 and the shell. Its main function is to regulate and control the flow of hydrogen entering the fuel cell stack 1 from the hydrogen storage container 6. The hydrogen inlet valve 7 may be opened or closed according to the needs of the system to control the supply of hydrogen. This control is to ensure that the system can obtain sufficient hydrogen when needed to maintain the electrochemical reaction, and to stop the hydrogen supply when the system is shut down or maintained to ensure the safety of the system.

[0045] like Figure 1As shown, the fuel cell system 101 also includes: a gas-liquid separator 8 and a drain valve 41. Among them, the gas-liquid separator 8 can be a device for separating gas and liquid. The inlet of the gas-liquid separator 8 is connected to the shell to receive the mixed gas and liquid flowing out of the shell, usually a mixture of hydrogen and water vapor. Inside the gas-liquid separator 8, it separates the gas and liquid through the principle of physical or gravity separation. The gas output port of the gas-liquid separator 8 is connected to the pipeline between the hydrogen storage container 6 and the shell, and the separated hydrogen is transmitted to the hydrogen storage container 6 to recover and store the hydrogen. The liquid output port of the gas-liquid separator 8 is connected to the drain pipe 4 to discharge the separated liquid (usually water) out of the system to remove the moisture in the shell and ensure the normal operation of the system.

[0046] It should be noted that although the gas-liquid separator 8 can effectively separate gas and liquid, it may not be able to completely separate hydrogen and water in actual operation. This means that some hydrogen may remain in the drain pipe 4. The residual hydrogen may be caused by performance limitations of the gas-liquid separator 8, gas solubility, gas leakage or other factors. These residual hydrogen may diffuse into the interior of the stack shell through the tail discharge or stack shell purge pipeline. Therefore, by setting the purge branch 5 and the purge control valve 51, the drain pipe 4 can be forcibly purged after the system is shut down to ensure that the residual hydrogen is effectively removed and prevented from diffusing into the interior of the stack shell, thereby improving the safety and performance of the system.

[0047] The drain valve 41 may be a control valve disposed at the liquid outlet of the gas-liquid separator 8, and is used to control and adjust the flow rate of the discharged wastewater. The drain valve 41 may be opened or closed according to the needs of the system to ensure that the water in the drain pipe 4 is effectively discharged, thereby helping to prevent water from accumulating on the anode side, reducing the risk of the hydrogen flow passage being blocked by water vapor, and thus maintaining the safety of the system.

[0048] In some embodiments, Figure 1 As shown, the fuel cell system 101 further includes: an air compressor 10 , an intercooler 20 , a humidifier 30 and a main exhaust pipe 40 .

[0049] The air compressor 10 may be a device for sucking air from the atmosphere and increasing its pressure by compressing it. This is to ensure that there is sufficient oxygen supply in the fuel cell stack 1 to support the electrochemical reaction. By compressing the air, the oxygen concentration, oxygen transmission rate, gas density, etc. can be increased, so that the fuel cell system 101 can generate electricity more efficiently.

[0050] The intercooler 20 may be a component for cooling the compressed air discharged from the air compressor 10. The input port of the intercooler 20 is connected to the discharge port of the air compressor 10, and the output port of the intercooler 20 is connected to the stack cavity purge air intake pipeline 2. The intercooler 20 may reduce the temperature of the air to prevent excessive heat from being generated before entering the stack 1. Cooling the air helps to improve the efficiency and stability of the stack 1.

[0051] The humidifier 30 can be used to increase the moisture content in the gas. The first input port of the humidifier 30 is connected to the output port of the intercooler 20. The first output port of the humidifier 30 is connected to the housing through the air inlet pipe 50 to introduce air into the housing. The second input port of the humidifier 30 is connected to the housing through the first exhaust pipe 70 to discharge the exhaust gas in the housing. In an embodiment, the exhaust gas discharged from the first exhaust pipe 70 can be relatively dry exhaust gas or gas containing a certain amount of moisture. The exhaust gas can flow back to the humidifier 30 to recover some moisture and improve system efficiency.

[0052] The main exhaust pipe 40 may be a pipe for discharging a mixture of exhaust gas and water vapor. The main exhaust pipe 40 is connected to the second output port of the humidifier 30, the stack cavity purge exhaust pipeline 3, and the drain pipe 4. The main exhaust pipe 40 discharges the exhaust gas from the system to maintain normal operation and ensures that the exhaust gas does not accumulate in the system, thereby maintaining the safety of the fuel cell system 101.

[0053] In some embodiments, the fuel cell system 101 further includes: a bypass line 60 and a bypass valve 61. The bypass line 60 is connected between the output port of the intercooler 20 and the main exhaust pipe 40. The bypass valve 61 is arranged on the bypass line 60, and its main function may be to control the on-off of the bypass line 60. By controlling the opening or closing of the bypass valve 61, the path of gas flow may be adjusted. The control of the bypass valve 61 may be used to adjust the operation and performance of the system to meet different working requirements.

[0054] In some embodiments, the fuel cell system 101 further includes: a hydrogen concentration sensor 11. The hydrogen concentration sensor 11 is usually disposed in the housing of the battery stack 1 and is used to monitor changes in the concentration of hydrogen in the battery stack cavity. The hydrogen concentration sensor 11 can detect whether the hydrogen concentration exceeds a safe range and, if necessary, trigger an alarm or take other measures to ensure the safe operation of the system. This helps to monitor and maintain the stability and performance of the battery system in real time, and take appropriate measures to prevent the hydrogen concentration from increasing, thereby improving the safety of the system.

[0055] Based on the fuel cell system described in the above embodiment, Figure 2 and Figure 3 A shutdown control method according to an embodiment of the present invention is described.

[0056] The shutdown control method of an embodiment of the present invention is used for a fuel cell system, which includes a stack cavity purge inlet pipeline and a stack cavity purge exhaust pipeline for purging the stack, and a drain pipe. A purge branch is arranged between the stack cavity purge exhaust pipeline and the drain pipe, and a purge control valve is arranged on the purge branch, so as to effectively treat the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the stack shell.

[0057] Figure 2 is a flow chart of a shutdown control method according to an embodiment of the present invention. Figure 2 As shown, the shutdown control method at least includes steps S1-S3, which are as follows:

[0058] S1, in response to the completion of electric propulsion drainage, controls the purge control valve to open, so as to purge the drainage pipe with gas in the discharge pipeline through the stack cavity.

[0059] In some embodiments, the system can use different methods to detect whether the drain pipe has been drained. For example, the system can install a pressure sensor near the drain pipe or drain valve to monitor the pressure or flow of wastewater discharge. When this sensor detects that the flow of wastewater stops or reaches a preset threshold, the system can automatically assume that the drainage has been completed. Alternatively, the system can start timing when the drainage operation is started, and the timer can send a signal after a preset period of time, indicating that the drain valve can be closed. This time can be set according to the needs of the system. Alternatively, the drain valve can generate an electronic signal or state change, and when the drain valve is turned from the drain position to the closed position, this signal can be detected, thereby triggering the purge operation. No specific restrictions are made here.

[0060] Specifically, when the drain valve finishes draining, the purge control valve is controlled to open and compressed gas is introduced from the stack cavity purge discharge pipeline. This gas will be guided into the drain pipe to help remove residual hydrogen. Among them, the controller can monitor the pressure of the gas to ensure that sufficient gas enters the drain pipe through the stack cavity purge discharge pipeline to effectively purge the residual hydrogen.

[0061] S2, record the time for blowing the drain pipe.

[0062] In some embodiments, the purpose of recording the time of purging the drain pipe is to monitor and manage the purging process of the drain pipe to ensure that the purging time is long enough to effectively remove the residual hydrogen, thereby improving the safety of the system. : Time recording can be achieved by a timer or real-time clock in the system. Specifically, when the purging operation is started in step S1, a timer can be started, and the timer will continue to count until the required purging time is reached. At this time, the system can record the time used, usually in minutes or hours. The record can be stored in the system's log file for the operator or monitoring system to view at any time.

[0063] S3, when the time for purging the drain pipe is reached, the purge control valve is controlled to close.

[0064] In some embodiments, the first preset time may be a time threshold value pre-set according to system requirements and performance considerations. It represents the minimum time required for drain pipe purge. The determination of the first preset time may take into account factors such as the length, diameter, hydrogen concentration of the exhaust pipe, and design parameters of the system. By testing the system in an experiment or simulation, an appropriate first preset time can be determined to ensure that the drain pipe is fully cleaned. The first preset time can be dynamically adjusted according to system requirements to adapt to different working conditions of the system. For example, if the system detects that there is a lot of hydrogen residue in the drain pipe, the first preset time can be set longer to ensure that the drain pipe is fully cleaned. Conversely, if the drain pipe is usually clean, the purge time can be shortened to improve system efficiency. Therefore, when the purge time reaches the first preset time, the controller controls the purge control valve to close and terminates the purge operation on the drain pipe.

[0065] According to the shutdown control method of an embodiment of the present invention, a purge branch and a purge control valve are set between the stack cavity purge exhaust pipeline and the drain pipe. After the system is drained, the purge control valve is controlled to open, and the drain pipe is forcibly purged by the gas in the stack cavity purge exhaust pipeline. When the purge time for the drain pipe reaches a first preset time, the purge control valve is controlled to close. This process can effectively deal with the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate in the system when it is shut down, thereby improving the safety of the fuel cell system and ensuring the normal operation of the battery.

[0066] In some embodiments, the fuel cell system also includes an air compressor for providing purge gas to the air intake line of the stack cavity, and the shutdown control method also includes: after controlling the purge control valve to close, controlling the air compressor to delay closing for a second preset time. This is to thoroughly purge the hydrogen that may remain in the tail exhaust to avoid residual hydrogen in the system pipeline after shutdown. The second preset time can be determined according to the needs of the system. It can be a pre-set time, or it can be determined by testing and monitoring system performance. In actual operation, the length of the second preset time can be adjusted according to the purge effect and safety requirements.

[0067] In some embodiments, the shutdown control method further includes: in response to a shutdown instruction, which is generally a signal generated by a system operator or an automatic control system to instruct the system to prepare for shutdown, controlling the anode intake valve of the fuel cell system to close, in order to stop the supply of hydrogen, thereby preventing new hydrogen from entering the fuel cell stack and ensuring that the fuel cell stack no longer receives fuel during shutdown.

[0068] Furthermore, the air compressor is controlled to continue to run, so as to continue to purge the fuel cell stack through the stack cavity purge air intake line to ensure that there is no residual hydrogen in the stack. Even if the stack has stopped supplying power, the purge operation still needs to be maintained until it is determined that there is no residual hydrogen. This helps to improve the safety of the system and ensure that the stack is in a safe state during shutdown.

[0069] In some embodiments, during the shutdown process, in order to discharge the waste water generated by the fuel cell, it is necessary to control the drain valve of the fuel cell to open so as to drain the water through the drain pipe. In addition, the system needs to record the time of draining the water through the drain pipe. This time record can be implemented using a timer or a clock inside the system. The purpose is to monitor the duration of waste water discharge. When the draining time of the drain pipe reaches a third preset time, it is determined that the drain valve has finished draining the water. The third preset time can be a pre-set time threshold, which can be adjusted according to system requirements. This time is usually long enough to ensure that the waste water is completely discharged.

[0070] Figure 3 is a flowchart of system shutdown purge according to one embodiment of the present invention. Figure 3 As shown, the system shutdown and purging includes at least steps S10-S18, which are as follows:

[0071] S10, system shutdown.

[0072] S11, introducing air into the shell through the air inlet pipe to purge the core inside the fuel cell stack.

[0073] S12, controlling the drain valve to open to drain water through the drain pipe.

[0074] S13, when the drainage time of the drainage pipe reaches the third preset time, the drainage valve is controlled to close.

[0075] S14, controls the purge control valve to open.

[0076] S15, the drain pipe is purged by purging the gas in the discharge pipeline through the stack cavity.

[0077] S16, when the time for purging the drain pipe reaches a first preset time, the purge control valve is controlled to close.

[0078] S17, controlling the air compressor to delay shutting down for a second preset time.

[0079] S18, end.

[0080] To summarize, by monitoring the drainage time, purge time and air compressor delay time, and controlling the drain valve and purge control valve for drainage and purge, the fuel cell system and shutdown control method of the present invention can efficiently deal with the residual hydrogen in the drain pipe and prevent the residual hydrogen from diffusing into the interior of the fuel cell stack shell, thereby improving the safety of the system and ensuring the normal operation of the battery.

[0081] Reference below Figure 4 A vehicle according to an embodiment of the present invention is described.

[0082] Figure 4 is a block diagram of a vehicle according to an embodiment of the present invention, Figure 4 As shown, a vehicle 100 includes a fuel cell system 101 described in the above embodiment.

[0083] According to the vehicle 100 of the embodiment of the present invention, by adopting the fuel cell system 101 described in the above embodiment, after discharging the waste water generated by the fuel cell, the purge control valve is controlled to open, and the stack cavity purge discharge pipeline flows air into the drain pipe through the purge branch to realize forced purge of the drain pipe, thereby effectively treating the residual hydrogen in the drain pipe and preventing the residual hydrogen from diffusing into the interior of the stack shell, ensuring that hydrogen will not accumulate when the system is in the shutdown state, thereby improving the safety of the fuel cell system 101 and ensuring the normal operation of the battery.

[0084] In some embodiments, the vehicle 100 may be various types of transportation, such as cars, buses, trucks, trains, etc. The integration of the fuel cell system 101 may enable these vehicles to use fuel cells as a power source to provide clean and efficient energy.

[0085] In practical applications, the vehicle 100 with this configuration can be widely used in various fields to meet the transportation needs of different purposes, and at the same time has the characteristics of environmental protection, high efficiency, and sustainability.

[0086] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0087] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A shutdown control method, characterized in that: For a fuel cell system, the fuel cell system comprises a stack cavity purge inlet pipeline and a stack cavity purge exhaust pipeline and a drain pipe for purging the stack, a purge branch is arranged between the stack cavity purge exhaust pipeline and the drain pipe, a purge control valve is arranged on the purge branch, and the shutdown control method comprises: In response to the completion of draining the stack, controlling the purge control valve to open, so as to purge the drain pipe with gas in the discharge pipeline through the stack cavity; Recording the time for blowing the drain pipe; When the time for purging the drain pipe reaches a first preset time, the purge control valve is controlled to close.

2. The shutdown control method according to claim 1, characterized in that: The fuel cell system further includes an air compressor for providing a purge gas to the purge air inlet pipeline of the fuel cell stack cavity, and the shutdown control method further includes: After controlling the purge control valve to close, controlling the air compressor to close after a delay of a second preset time.

3. The shutdown control method according to claim 2, characterized in that: The shutdown control method further includes: In response to a shutdown instruction, the anode air intake valve of the fuel cell system is controlled to be closed, and the air compressor is controlled to continue to run to continue to purge the fuel cell stack through the stack cavity purge air intake line.

4. The shutdown control method according to claim 3, characterized in that: The shutdown control method further includes: controlling a drain valve of the fuel cell to open so as to drain water through the drain pipe; Recording the time when the drain pipe is drained; When the drainage time of the drainage pipe reaches a third preset time, it is determined that the drainage of the drainage valve is completed.

5. A fuel cell system, characterized in that: include: A fuel cell stack, the fuel cell stack comprising a shell and a core; A fuel cell stack cavity purge air inlet pipeline connected to the shell and used to introduce air into the shell to purge the gap between the shell and the core; A stack cavity purge discharge pipeline connected to the shell and used to discharge the exhaust gas in the gap; A drain pipe connected to the housing and used to drain waste water generated by the fuel cell; A purge branch, the purge branch being arranged between the stack cavity purge exhaust pipeline and the drain pipe; A purge control valve, the purge control valve is arranged on the purge branch to control the on-off of the purge branch; A controller, used to execute the shutdown control method described in any one of claims 1-4.

6. The fuel cell system according to claim 5, characterized in that: The fuel cell system further comprises: A hydrogen storage container, wherein the gas outlet of the hydrogen storage container is connected to the shell so as to allow hydrogen to flow into the shell; A hydrogen inlet valve is arranged on a pipeline between the hydrogen storage container and the shell to control the hydrogen gas introduced into the shell.

7. The fuel cell system according to claim 6, characterized in that: The fuel cell system further comprises: A gas-liquid separator, wherein the inlet of the gas-liquid separator is connected to the shell, the gas outlet of the gas-liquid separator is connected to the pipeline between the hydrogen storage container and the shell, and the liquid outlet of the gas-liquid separator is connected to the drain pipe; A drain valve is arranged at the liquid output port of the gas-liquid separator.

8. The fuel cell system according to claim 7, characterized in that: The fuel cell system further comprises: Air compressor; An intercooler, wherein the input port of the intercooler is connected to the discharge port of the air compressor, and the output port of the intercooler is connected to the purge air intake pipeline of the fuel cell cavity; a humidifier, wherein a first input port of the humidifier is connected to an output port of the intercooler, the first output port of the humidifier is connected to the housing through an air intake pipe to allow air to flow into the housing, and a second input port of the humidifier is connected to the housing through a first exhaust pipe to exhaust exhaust gas in the housing; A main exhaust pipe is connected to the second output port of the humidifier, the stack cavity purge exhaust pipeline, and the drain pipe respectively.

9. The fuel cell system according to claim 8, characterized in that: The fuel cell system further comprises: A bypass pipeline connected between the output port of the intercooler and the main exhaust pipe; A bypass valve is arranged on the bypass pipeline.

10. A vehicle, characterized in that: A fuel cell system comprising any one of claims 5-9.

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