Fuel cell system, air flow control method thereof, and vehicle

Abstract

The present invention discloses a fuel cell system and an air flow control method thereof, as well as a vehicle. The method includes the following steps: obtaining the current expected load current of the fuel cell stack in the fuel cell system; setting the air mass flow of the fuel cell stack according to the current expected load current; obtaining the actual load current and actual air mass flow of the fuel cell stack; judging whether the fuel cell stack will experience oxygen starvation based on the actual load current and actual air mass flow; if the fuel cell stack will experience oxygen starvation, obtaining the current maximum load current of the fuel cell stack based on the actual air mass flow; and controlling the fuel cell system to operate at a power limit based on the current maximum load current. Thus, when insufficient oxygen is supplied to the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at a power limit based on the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

Description

Technical Field

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

[0002] Fuel cells are a clean, efficient, environmentally friendly and reliable energy source. With the continuous consumption of fossil energy and the increasing awareness of environmental protection, fuel cells have been widely promoted as an alternative to traditional internal combustion engines.

[0003] There are many types of fuel cells, among which PEM (Proton Exchange Membrane) fuel cells are widely used in the automotive field due to their excellent performance. PEM fuel cells are composed of a cathode, an electrolyte membrane, and an anode. The anode of the PEM fuel cell receives hydrogen gas, and the cathode receives oxygen gas. The hydrogen and oxygen undergo an electrochemical reaction at the electrolyte membrane, generating electricity for use. The oxygen to the cathode of a PEM fuel cell is usually supplied by an air compressor. However, when the air compressor capacity is limited or the flow controller fails, the fuel cell cathode will be insufficiently supplied with oxygen. If the vehicle continues to maintain the original power load, it is easy to cause the stack voltage to drop sharply and damage the electrolyte membrane, which will seriously shorten the life of the stack. Summary of the Invention

[0004] The present invention aims to at least partially address one of the technical problems in the related art. To this end, the first object of the present invention is to provide an air flow control method for a fuel cell system. This method can control the fuel cell system to operate at a limited power level based on the current maximum load current when oxygen is insufficient on the cathode side of the fuel cell system. This method avoids oxygen starvation caused by the vehicle maintaining its original power level due to oxygen deficiency, effectively extending the service life of the fuel cell stack.

[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] To achieve the above-mentioned objectives, an embodiment of the first aspect of the present invention proposes an air flow control method for a fuel cell system, comprising the following steps: obtaining the current expected load current of the fuel cell stack in the fuel cell system; setting the air mass flow of the fuel cell stack according to the current expected load current; obtaining the actual load current and the actual air mass flow of the fuel cell stack; judging whether the fuel cell stack will experience oxygen starvation based on the actual load current and the actual air mass flow; if the fuel cell stack will experience oxygen starvation, obtaining the current maximum load current of the fuel cell stack based on the actual air mass flow; and controlling the fuel cell system to operate at limited power based on the current maximum load current.

[0008] According to the air flow control method of the fuel cell system of an embodiment of the present invention, the air mass flow of the fuel cell stack is set by obtaining the current expected load current of the fuel cell stack in the fuel cell system, and the actual load current and actual air mass flow of the fuel cell stack are obtained to determine whether the fuel cell stack will experience oxygen starvation. If the fuel cell stack will experience oxygen starvation, the current maximum load current of the fuel cell stack is obtained according to the actual air mass flow, and the fuel cell system is controlled to operate at a power limit according to the current maximum load current. As a result, when insufficient oxygen is supplied to the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at a power limit according to the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

[0009] According to one embodiment of the present invention, the above-mentioned air flow control method of the fuel cell system further includes: if the fuel cell stack does not experience oxygen starvation, controlling the fuel cell system to output corresponding power according to the current power demand of the load corresponding to the fuel cell system.

[0010] According to one embodiment of the present invention, obtaining the current expected load current of the fuel cell stack in the fuel cell system includes: obtaining the current power demand of the load corresponding to the fuel cell system; and obtaining the current expected load current of the fuel cell stack based on the current power demand.

[0011] According to one embodiment of the present invention, whether the fuel cell stack will experience oxygen starvation is determined based on the actual loading current and the actual air mass flow rate, including: obtaining the oxygen stoichiometric ratio based on the actual loading current and the actual air mass flow rate; if the oxygen stoichiometric ratio is less than a preset oxygen stoichiometric ratio, determining that the fuel cell stack will experience oxygen starvation; if the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, determining that the fuel cell stack will not experience oxygen starvation.

[0012] To achieve the above-mentioned purpose, the second embodiment of the present invention proposes a fuel cell system, comprising: a fuel cell stack, a hydrogen module, an air supply module, a detection module and a control module, wherein the hydrogen module is connected to the anode of the fuel cell stack for providing hydrogen to the fuel cell stack; the air supply module is connected to the cathode of the fuel cell stack for providing air to the fuel cell stack; the detection module is arranged at the cathode inlet of the fuel cell stack for obtaining the actual air mass flow at the cathode inlet of the fuel cell stack; the control module is connected to the air supply module and the detection module respectively, for obtaining the current expected load current of the fuel cell stack, and controlling the air supply module according to the current expected load current to set the air mass flow of the fuel cell stack, as well as obtaining the actual load current and the actual air mass flow of the fuel cell stack, and judging whether the fuel cell stack will experience oxygen starvation based on the actual load current and the actual air mass flow, and when the fuel cell stack will experience oxygen starvation, obtaining the current maximum load current of the fuel cell stack according to the actual air mass flow, and controlling the fuel cell system to limit power operation based on the current maximum load current.

[0013] According to the fuel cell system of an embodiment of the present invention, the current expected load current of the fuel cell stack in the fuel cell system is obtained by the control module to set the air mass flow of the fuel cell stack, and the actual load current and actual air mass flow of the fuel cell stack are obtained by the control module to determine whether the fuel cell stack will experience oxygen starvation. If the fuel cell stack will experience oxygen starvation, the current maximum load current of the fuel cell stack is obtained based on the actual air mass flow, and the fuel cell system is controlled to operate at a power limit based on the current maximum load current. As a result, when insufficient oxygen is supplied to the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at a power limit based on the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

[0014] According to one embodiment of the present invention, the control module is further configured to control the fuel cell system to output corresponding power according to the current power demand of the load corresponding to the fuel cell system when the fuel cell stack does not suffer from oxygen starvation.

[0015] According to one embodiment of the present invention, the control module is specifically configured to: obtain a current power demand of a load corresponding to the fuel cell system, and obtain a current expected load current of the fuel cell stack based on the current power demand.

[0016] According to one embodiment of the present invention, the control module is specifically used to: obtain the oxygen stoichiometric ratio based on the actual load current and the actual air mass flow rate; if the oxygen stoichiometric ratio is less than the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will experience oxygen starvation; if the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will not experience oxygen starvation.

[0017] According to one embodiment of the present invention, the air supply module includes: a filter, an air compressor and a humidifier, the gas outlet of the filter is connected to the gas inlet of the air compressor, the gas outlet of the air compressor is connected to the cathode inlet of the fuel cell stack through the humidifier, and the control module is connected to the air compressor. The control module is specifically used to control the air compressor to set the air mass flow rate of the fuel cell stack.

[0018] To achieve the above-mentioned objectives, a third embodiment of the present invention provides a vehicle comprising a fuel cell system as described in the second embodiment.

[0019] According to the vehicle of an embodiment of the present invention, through the above-mentioned fuel cell system, when insufficient oxygen supply occurs on the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at limited power according to the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

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

[0021] Figure 1 is a flow chart of an air flow control method for a fuel cell system according to one embodiment of the present invention;

[0022] Figure 2 A schematic structural diagram of a fuel cell system according to one embodiment of the present invention;

[0023] Figure 3 is a schematic structural diagram of a fuel cell system according to another embodiment of the present invention;

[0024] Figure 4 FIG. 1 is a schematic structural diagram of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0026] The fuel cell system, air flow control method thereof, and vehicle provided by embodiments of the present invention will be described below with reference to the accompanying drawings.

[0027] In order to better explain the air flow control method of the fuel cell system of the present application, it can be combined with Figure 3 The fuel cell system shown is described as follows: Figure 3 As shown, the fuel cell system may include: a fuel cell stack 10, a hydrogen module 20, a filter 31, an air compressor 32, a humidifier 33, a detection module 40, and a control module 50. The hydrogen module 20 is connected to the anode of the fuel cell stack 10 to provide hydrogen to the anode of the fuel cell stack 10. The gas inlet of the air compressor 32 is connected to the filter 31, and the gas outlet is connected to the cathode inlet of the fuel cell stack 10 through the humidifier 30. Air is sucked from the atmosphere by the air compressor 32 and filtered through the filter 31 to remove dust in the air and prevent large particles from clogging the flow channel. After being humidified inside the air compressor 32 and humidified by the humidifier 33, it is sent to the cathode of the fuel cell stack 10 to ensure that the proton exchange membrane is in a suitable water saturation state, so that it maintains a high conductivity, thereby allowing the fuel cell stack 10 to operate normally and output a specific power. The air compressor 32 can be any appropriate air compressor capable of providing compressed air, such as a vane air compressor, a screw air compressor, a scroll air compressor, and a centrifugal air compressor. The detection module 40 is provided at the gas inlet of the air compressor 32 and is used to detect the mass flow of air entering the fuel cell stack 10. In a specific implementation, the detection module 40 can be a flow meter for measuring the rate of the air mass flow through the air compressor 32 and generating a voltage signal representing the rate of the air mass flow through the flow meter. Since the rate of the air mass flow in the same flow channel is consistent, the air mass flow rate monitored by the flow meter can be used to represent the air mass flow rate of the fuel cell stack 10. The control module 50 is connected to the detection module 40 and the air compressor 32 respectively, and is used to obtain the air mass flow detected by the detection module 50 and control the speed of the air compressor 32 to achieve control of the air mass flow of the fuel cell stack 10. The control module 50 has a calculation function for calculating the oxygen stoichiometric ratio and performing starvation judgment based on the load current, and calculating the maximum load current that the fuel cell stack 10 can provide based on the current actual air mass flow.

[0028] Figure 1 FIG. 1 is a flow chart of an air flow control method for a fuel cell system according to an embodiment of the present invention. Figure 1 As shown, the air flow control method of the fuel cell system includes the following steps:

[0029] Step S101: obtaining the current expected load current of the fuel cell stack in the fuel cell system.

[0030] It can be understood that since the fuel cell system is used to provide electrical energy to the load, the current expected load current of the fuel cell stack in the fuel cell system can be obtained according to the load demand, where the load current refers to the current pulled out from the fuel cell stack, that is, the current obtained by the load from the fuel cell stack.

[0031] Optionally, obtaining the current expected load current of the fuel cell stack in the fuel cell system includes: obtaining the current power demand of the load corresponding to the fuel cell system; and obtaining the current expected load current of the fuel cell stack according to the current power demand.

[0032] Specifically, the control module 50 can obtain the current power demand of the load and, based on the current power demand, obtain the corresponding expected load current. The power demand and the expected load current are directly proportional, i.e., the greater the power demand, the greater the expected load current. In a specific implementation, when the present application is applied to a vehicle, the control module 50 can obtain the corresponding expected load current based on the vehicle's current power demand, i.e., the current that the vehicle needs to draw from the fuel cell stack.

[0033] Step S102: setting the air mass flow rate of the fuel cell stack according to the current expected load current.

[0034] It should be noted that air mass flow rate represents the mass of air flowing through per unit time. After obtaining the current desired load current, the control module 50 can set the air mass flow rate of the fuel cell stack based on the current desired load current. In specific implementations, the control parameters of the air compressor 32 can be determined based on the current desired load current, and the air compressor 32 can be controlled according to the control parameters so that the air compressor 32 outputs an air mass flow rate corresponding to the current desired load current. The air mass flow rate output by the air compressor 32 is the air mass flow rate of the fuel cell stack.

[0035] Step S103: Acquire the actual load current and actual air mass flow of the fuel cell stack.

[0036] Specifically, after the air mass flow of the fuel cell stack is set according to the current desired load current, under normal circumstances, the actual air mass flow output by the air compressor 32 is the same as or very close to the air mass flow corresponding to the current desired load current. However, when the capacity of the air compressor 32 is limited or the flow controller fails, the actual air mass flow output by the air compressor 32 will not reach the air mass flow corresponding to the current desired load current. At this time, it may cause insufficient oxygen supply to the cathode of the fuel cell stack in the fuel cell system. Therefore, the control module 50 will obtain the actual load current and the actual air mass flow of the fuel cell stack. In specific implementation, the actual load current is provided by the load. Taking the application of this application to a vehicle as an example, the vehicle will obtain the actual load current in real time during operation and feed the actual load current back to the control module 50. At the same time, the control module 50 obtains the actual air mass flow of the fuel cell stack through the detection module 40.

[0037] Step S104 , judging whether the fuel cell stack will experience oxygen starvation based on the actual load current and the actual air mass flow rate.

[0038] Among them, judging whether the fuel cell stack will experience oxygen starvation is based on the actual load current and the actual air mass flow, including: obtaining the oxygen stoichiometric ratio based on the actual load current and the actual air mass flow; if the oxygen stoichiometric ratio is less than the preset oxygen stoichiometric ratio, judging that the fuel cell stack will experience oxygen starvation; if the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, judging that the fuel cell stack will not experience oxygen starvation.

[0039] Specifically, the control module 50 can calculate the oxygen stoichiometric ratio based on the number of cells in the fuel cell system, the Faraday constant, the actual loading current and the actual air mass flow rate (specifically, it can be implemented using existing technology), and compare it with the preset oxygen stoichiometric ratio to determine whether the stack will be starved if it continues to load under the current conditions. When the calculated oxygen stoichiometric ratio is less than the preset oxygen stoichiometric ratio, it is determined that the stack has experienced oxygen starvation, that is, insufficient oxygen supply occurs at the cathode of the fuel cell stack, and when the calculated oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, it is determined that the stack has not experienced oxygen starvation, indicating that the fuel cell system is operating well. It should be noted that the preset oxygen stoichiometric ratio can be provided by the stack supplier and used as a system operation restriction condition.

[0040] Step S105: If the fuel cell stack is experiencing oxygen starvation, the current maximum load current of the fuel cell stack is obtained according to the actual air mass flow rate.

[0041] Specifically, after oxygen starvation occurs in the fuel cell stack, the control module 50 can reversely calculate the load current that the fuel cell stack can generate under the current actual air mass flow conditions based on the number of fuel cell stack cells, the Faraday constant, the actual air mass flow rate and the preset oxygen stoichiometric ratio of the fuel cell system. The load current calculated at this time is the maximum load current that the fuel cell stack can generate under the current conditions without oxygen starvation, that is, the maximum load current allowed by the current fuel cell stack.

[0042] Step S106 , controlling the fuel cell system to operate at limited power according to the current maximum load current.

[0043] Specifically, when the fuel cell stack is starved of oxygen, if the vehicle maintains the original power and continues to load, it will cause insufficient oxygen supply to the cathode of the fuel cell stack. If this phenomenon is not adjusted, it will cause the fuel cell stack voltage to drop sharply and the electrolyte membrane to be damaged, which will seriously affect the service life of the fuel cell stack. Therefore, when the fuel cell stack is starved of oxygen, the control module 50 will control the fuel cell system to limit the power operation according to the current maximum load current, even if the output power of the fuel cell system is reduced to solve the problem of insufficient oxygen supply to the cathode of the fuel cell stack. That is to say, by reducing the expected load current of the fuel cell system to control the fuel cell system to limit the power operation, the oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen is solved, thereby ensuring that the system can operate stably under current conditions.

[0044] In some embodiments of the present invention, if the stack is not experiencing oxygen starvation, the fuel cell system is controlled to output power based on the current power demand of the load corresponding to the fuel cell system. That is, when the stack cathode oxygen supply is sufficient, the fuel cell system continues to generate the corresponding load current according to the power demand of the load, without the need to adjust the load current, i.e., the fuel cell system is not power-limited.

[0045] In summary, according to the air flow control method of the fuel cell system according to an embodiment of the present invention, the air mass flow of the fuel cell stack is set by obtaining the current expected load current of the fuel cell stack in the fuel cell system, and the actual load current and actual air mass flow of the fuel cell stack are obtained to determine whether the fuel cell stack will experience oxygen starvation. If the fuel cell stack will experience oxygen starvation, the current maximum load current of the fuel cell stack is obtained according to the actual air mass flow, and the fuel cell system is controlled to operate at a power limit according to the current maximum load current. As a result, when insufficient oxygen is supplied to the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at a power limit according to the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

[0046] Figure 2 FIG. 1 is a schematic structural diagram of a fuel cell system according to an embodiment of the present invention. Figure 2 As shown, the fuel cell system includes: a fuel cell stack 10 , a hydrogen module 20 , an air supply module 30 , a detection module 40 and a control module 50 .

[0047] Among them, the hydrogen module 20 is connected to the anode of the fuel cell stack 10 for providing hydrogen to the fuel cell stack 10; the air supply module 30 is connected to the cathode of the fuel cell stack 10 for providing air to the fuel cell stack 10; the detection module 40 is arranged at the cathode inlet of the fuel cell stack 10 for obtaining the actual air mass flow at the cathode inlet of the fuel cell stack 10; the control module 50 is connected to the air supply module 30 and the detection module 40 respectively, for obtaining the current expected load current of the fuel cell stack 10, and controlling the air supply module 30 according to the current expected load current to set the air mass flow of the fuel cell stack 10, as well as obtaining the actual load current and the actual air mass flow of the fuel cell stack 10, and judging whether the fuel cell stack 10 will experience oxygen starvation according to the actual load current and the actual air mass flow, and when the fuel cell stack 10 will experience oxygen starvation, obtaining the current maximum load current of the fuel cell stack 10 according to the actual air mass flow, and controlling the fuel cell system to limit power operation according to the current maximum load current.

[0048] In some embodiments of the present invention, the control module 50 is further configured to control the fuel cell system to output corresponding power according to the current power demand of the load corresponding to the fuel cell system when the fuel cell stack 10 does not suffer from oxygen starvation.

[0049] In some embodiments of the present invention, the control module 50 is specifically used to obtain the current power demand of the load corresponding to the fuel cell system, and obtain the current expected load current of the fuel cell stack 10 according to the current power demand.

[0050] In some embodiments of the present invention, the control module 50 is specifically used to: obtain the oxygen stoichiometric ratio based on the actual load current and the actual air mass flow rate; if the oxygen stoichiometric ratio is less than the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack 10 will experience oxygen starvation; if the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack 10 will not experience oxygen starvation.

[0051] In some embodiments of the present invention, Figure 3 As shown, the air supply module 30 includes: a filter 31, an air compressor 32 and a humidifier 33. The gas outlet of the filter 31 is connected to the gas inlet of the air compressor 32, and the gas outlet of the air compressor 32 is connected to the cathode inlet of the fuel cell stack 10 through the humidifier 33. The control module 50 is connected to the air compressor 32. The control module 50 is specifically used to control the air compressor 32 to set the air mass flow rate of the fuel cell stack 10.

[0052] It should be noted that for the description of the fuel cell system in this application, please refer to the description of the air flow control method of the fuel cell system in this application, and the details will not be repeated here.

[0053] According to the fuel cell system of an embodiment of the present invention, the current expected load current of the fuel cell stack in the fuel cell system is obtained by the control module to set the air mass flow of the fuel cell stack, and the actual load current and actual air mass flow of the fuel cell stack are obtained by the control module to determine whether the fuel cell stack will experience oxygen starvation. If the fuel cell stack will experience oxygen starvation, the current maximum load current of the fuel cell stack is obtained based on the actual air mass flow, and the fuel cell system is controlled to operate at a power limit based on the current maximum load current. As a result, when insufficient oxygen is supplied to the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at a power limit based on the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

[0054] An embodiment of the present invention further provides a vehicle 1000 including the fuel cell system 100 according to the above embodiment.

[0055] According to the vehicle of an embodiment of the present invention, through the above-mentioned fuel cell system, when insufficient oxygen supply occurs on the cathode side of the fuel cell system, the fuel cell system can be controlled to operate at limited power according to the current maximum load current, thereby avoiding oxygen starvation caused by the vehicle maintaining the original power and continuing to load due to insufficient oxygen, and effectively improving the service life of the fuel cell stack.

[0056] It should be noted that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0057] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0058] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0059] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0060] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0061] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for controlling air flow in a fuel cell system, characterized in that: The following steps are involved: Obtaining a current expected load current of the fuel cell stack in the fuel cell system; Setting the air mass flow of the stack according to the current expected load current; Obtaining an actual load current and an actual air mass flow rate of the fuel cell stack; Determining whether the fuel cell stack will experience oxygen starvation according to the actual load current and the actual air mass flow rate; If the fuel cell stack experiences oxygen starvation, obtaining the current maximum load current of the fuel cell stack according to the actual air mass flow rate; Controlling the fuel cell system to operate at limited power according to the current maximum load current; The determining, based on the actual load current and the actual air mass flow rate, whether the fuel cell stack will experience oxygen starvation includes: Obtaining an oxygen stoichiometric ratio according to the actual load current and the actual air mass flow rate; If the oxygen stoichiometric ratio is less than a preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will experience the oxygen starvation phenomenon; If the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will not experience the oxygen starvation phenomenon.

2. The air flow control method of the fuel cell system according to claim 1, wherein: Also includes: If the fuel cell stack does not experience the oxygen starvation phenomenon, the fuel cell system is controlled to output corresponding power according to the current power demand of the load corresponding to the fuel cell system.

3. The air flow control method of the fuel cell system according to claim 1, wherein: The obtaining of the current expected load current of the fuel cell stack in the fuel cell system includes: Obtaining a current power demand of a load corresponding to the fuel cell system; A current expected load current of the fuel cell stack is obtained according to the current power demand.

4. A fuel cell system, characterized in that: include: Fuel cell, hydrogen module, air supply module, detection module and control module, among which, The hydrogen module is connected to the anode of the fuel cell stack and is used to provide hydrogen to the fuel cell stack; The air supply module is connected to the cathode of the fuel cell stack and is used to provide air to the fuel cell stack; The detection module is provided at the cathode inlet of the fuel cell stack and is used to obtain the actual air mass flow at the cathode inlet of the fuel cell stack; The control module is connected to the air supply module and the detection module, respectively, and is used to obtain a current expected load current of the fuel cell stack, and control the air supply module according to the current expected load current to set the air mass flow rate of the fuel cell stack, and obtain an actual load current and an actual air mass flow rate of the fuel cell stack, and determine whether the fuel cell stack will experience oxygen starvation according to the actual load current and the actual air mass flow rate, and when the fuel cell stack will experience oxygen starvation, obtain a current maximum load current of the fuel cell stack according to the actual air mass flow rate, and control the fuel cell system to operate with limited power according to the current maximum load current; The control module is specifically used for: Obtaining an oxygen stoichiometric ratio according to the actual load current and the actual air mass flow rate; If the oxygen stoichiometric ratio is less than a preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will experience the oxygen starvation phenomenon; If the oxygen stoichiometric ratio is greater than or equal to the preset oxygen stoichiometric ratio, it is determined that the fuel cell stack will not experience the oxygen starvation phenomenon.

5. The fuel cell system according to claim 4, wherein: The control module is further configured to control the fuel cell system to output corresponding power according to a current power demand of a load corresponding to the fuel cell system when the oxygen starvation phenomenon does not occur in the fuel cell stack.

6. The fuel cell system according to claim 4, wherein: The control module is specifically used to obtain a current power demand of a load corresponding to the fuel cell system, and obtain a current expected load current of the fuel cell stack according to the current power demand.

7. The fuel cell system according to claim 4, wherein: The air supply module includes: a filter, an air compressor and a humidifier. The gas outlet of the filter is connected to the gas inlet of the air compressor, and the gas outlet of the air compressor is connected to the cathode inlet of the fuel cell stack through the humidifier. The control module is connected to the air compressor, and the control module is specifically used to control the air compressor to set the air mass flow rate of the fuel cell stack.

8. A vehicle, characterized in that: A fuel cell system comprising the fuel cell system according to any one of claims 4 to 7.

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