Fuel cell gas supply system and gas supply method

Abstract

The embodiment of the invention provides a fuel cell gas supply system and a gas supply method, and relates to the technical field of cells. The air supply system comprises an air filter, a turbocharger, a three-way proportional valve, an air compressor, a three-way valve and an electric pile of a fuel cell; the electric pile comprises a cathode inlet and a cathode outlet; the three-way proportional valve comprises an inlet, a first channel and a second channel; the three-way valve comprises an inlet, a first channel and a second channel; an outlet of the air filter is connected with a first branch and a second branch, the first branch is connected to an inlet of the three-way proportional valve, the second branch is connected with a second channel of the three-way proportional valve through the turbocharger, and the first channel of the three-way proportional valve is connected with a cathode inlet of the electric pile through the air compressor; a cathode outlet of the electric pile is connected to an inlet of the three-way valve, a first channel of the three-way valve is used for direct exhaust, and a second channel of the three-way valve is used for exhaust through the turbocharger. Therefore, the fuel cell can stably supply air, and the energy consumption of the air compressor is effectively reduced.

Description

Technical Field

[0001] The embodiments described in this specification relate to the field of battery technology, specifically to a fuel cell gas supply system and gas supply method. Background Technology

[0002] Fuel cells, especially proton exchange membrane fuel cells, are highly efficient and clean energy conversion devices with broad application prospects in transportation, power supply, aerospace, and many other fields. Their performance is highly dependent on the supply pressure and flow rate of the cathode-side oxidant, such as air.

[0003] In related technologies, to maintain the necessary oxygen partial pressure inside the fuel cell to ensure electrochemical reaction efficiency, the air compressor must significantly increase its compression ratio. This can easily cause its operating point to approach or even enter the surge region, leading to component damage and system instability. While supplying oxygen to the fuel cell by setting up a high-pressure oxygen storage tank can directly increase the oxygen concentration of the gas entering the stack, it requires an additional high-pressure oxygen storage tank, which increases the size, weight, complexity, and cost of the fuel cell. Furthermore, ensuring a continuous supply of oxygen is a practical challenge.

[0004] Therefore, there is an urgent need to provide a fuel cell gas supply system to ensure stable gas supply and effectively reduce the energy consumption of air compressors. Summary of the Invention

[0005] In view of this, various embodiments of this specification aim to provide a fuel cell gas supply system and gas supply method to stabilize gas supply and effectively reduce air compressor energy consumption.

[0006] This specification provides a fuel cell gas supply system, including an air filter, a turbocharger, a three-way proportional valve, an air compressor, a three-way valve, and a fuel cell stack. The fuel cell stack includes a cathode inlet and a cathode outlet. The three-way proportional valve includes an inlet, a first channel, and a second channel. Along the intake direction, the outlet of the air filter is connected to a first branch and a second branch. The first branch of the air filter is connected to the inlet of the three-way proportional valve, and the second branch of the air filter is connected to the second channel of the three-way proportional valve via the turbocharger. The first channel of the three-way proportional valve is connected to the cathode inlet of the fuel cell stack via the air compressor to supply gas to the fuel cell stack. Along the exhaust direction, the cathode outlet of the fuel cell stack is connected to the inlet of the three-way valve. The first channel of the three-way valve is used for direct exhaust, and the second channel of the three-way valve is used for exhaust via the turbocharger.

[0007] In some embodiments, an intake flow meter is installed at the outlet of the air filter; the inlet of the three-way proportional valve is used to receive unpressurized air from the air filter; the second channel of the three-way proportional valve is connected to the compressor outlet of the turbocharger, and the second channel of the three-way proportional valve is used to receive pressurized air from the compressor outlet of the turbocharger; a first pressure sensor is installed between the first channel of the three-way proportional valve and the air compressor, and the first channel of the three-way proportional valve is used to output mixed air.

[0008] In some embodiments, a back pressure valve is provided between the cathode outlet of the fuel cell stack and the inlet of the three-way valve; the second channel of the three-way valve is connected to the turbine inlet of the turbocharger.

[0009] In some embodiments, along the intake direction, an intercooler and a shut-off valve are sequentially arranged between the air compressor and the cathode inlet of the fuel cell stack; a second pressure sensor is arranged between the shut-off valve and the cathode inlet of the fuel cell stack; the air supply system further includes a bypass branch, one end of which is connected to the pipeline between the intercooler and the shut-off valve, and the other end is connected to the inlet of the three-way valve; the bypass branch is sequentially equipped with a bypass flow meter and a bypass valve; when the first channel of the three-way valve is open and the second channel is closed, it is used to directly discharge the exhaust gas input into the inlet of the three-way valve; when the first channel of the three-way valve is closed and the second channel is open, it is used to direct the exhaust gas input into the inlet of the three-way valve to the turbine of the turbocharger to drive the turbocharger.

[0010] This specification provides a fuel cell gas supply method, applied to the fuel cell gas supply system described in any of the above embodiments. The gas supply method includes: acquiring atmospheric pressure; determining a target gas supply mode based on the atmospheric pressure; wherein the target gas supply mode includes a low-altitude mode or a high-altitude mode; and supplying gas to the fuel cell stack based on the target gas supply mode.

[0011] In some embodiments, determining the target gas supply mode based on the atmospheric pressure includes: if the atmospheric pressure is greater than or equal to a preset pressure threshold, the target gas supply mode adopts the low-altitude mode; otherwise, the target gas supply mode adopts the high-altitude mode; wherein the atmospheric pressure is read from a first pressure sensor in the fuel cell gas supply system.

[0012] In some implementations, the preset pressure threshold is 90 kPa.

[0013] In some embodiments, supplying air to the fuel cell stack based on the target air supply mode includes: when the target air supply mode is the low-altitude mode, controlling the first channel of the three-way proportional valve to open and the second channel to close, so that all intake air from the air filter does not flow through the turbocharger; controlling the first channel of the three-way valve to open and the second channel to close, so that all exhaust gas entering through the three-way valve does not flow through the turbine of the turbocharger and is directly discharged; and controlling the speed of the air compressor and the opening of the back pressure valve in a closed loop based on the pressure and flow requirements of the fuel cell stack's cathode inlet.

[0014] In some embodiments, supplying air to the fuel cell stack based on the target air supply mode includes: when the target air supply mode is the high-altitude mode, controlling the second channel of the three-way valve to open and the first channel to close, so that all exhaust gas flowing through the inlet of the three-way valve flows through the turbine of the turbocharger to provide driving force to the turbocharger; obtaining the opening command of the three-way proportional valve based on the pressure demand at the cathode inlet of the fuel cell stack and the difference between the pressure sensor in the fuel cell air supply system and the pressure demand at the cathode inlet of the fuel cell stack, as input to the proportional-integral controller; controlling the three-way proportional valve based on the opening command to adjust the mixing ratio of unpressurized air from the air filter and pressurized air from the turbocharger compressor; wherein the opening command represents the volume or mass flow rate ratio of the pressurized air from the turbocharger in the air flowing to the air compressor inlet; and controlling the speed of the air compressor and the opening of the back pressure valve in a closed loop according to the pressure and flow demand at the cathode inlet of the fuel cell stack.

[0015] In some implementations, when the target gas supply mode is the high-altitude mode, the pressure requirement at the cathode inlet of the fuel cell stack is one standard atmosphere.

[0016] In several embodiments provided in this specification, the fuel cell gas supply system includes an air filter, a turbocharger, a three-way proportional valve, an air compressor, a three-way valve, and a fuel cell stack. The fuel cell stack includes a cathode inlet and a cathode outlet. The three-way proportional valve includes an inlet, a first channel, and a second channel. Along the intake direction, the outlet of the air filter is connected to a first branch and a second branch. The first branch of the air filter is connected to the inlet of the three-way proportional valve, and the second branch of the air filter is connected to the second channel of the three-way proportional valve via the turbocharger. The first channel of the three-way proportional valve is connected to the cathode inlet of the fuel cell stack via the air compressor to supply gas to the fuel cell stack. Along the exhaust direction, the cathode outlet of the fuel cell stack is connected to the inlet of the three-way valve. The first channel of the three-way valve is used for direct exhaust, and the second channel of the three-way valve is used for exhaust via the turbocharger. This allows the fuel cell to supply gas stably and effectively reduces the energy consumption of the air compressor. Attached Figure Description

[0017] Figure 1 A schematic diagram of a fuel cell gas supply system provided for embodiments of this specification; Figure 2 A schematic flowchart of a fuel cell gas supply method provided in the embodiments of this specification; Figure 3 Another schematic flowchart illustrating the fuel cell gas supply method provided in the embodiments of this specification; Figure 4 This is yet another schematic flowchart illustrating the fuel cell gas supply method provided in the embodiments of this specification. Detailed Implementation

[0018] To enable those skilled in the art to better understand the solutions described in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of them. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0019] This specification provides a fuel cell gas supply system. Please refer to [link / reference]. Figure 1 , Figure 1This is a schematic diagram of a fuel cell gas supply system provided in the embodiments of this specification. The fuel cell gas supply system may include an air filter 101, a turbocharger 114, a three-way proportional valve 103, an air compressor 105, a three-way valve 113, and a fuel cell stack 109; the fuel cell stack 109 includes a cathode inlet and a cathode outlet; the three-way proportional valve 103 includes an inlet, a first channel 1031, and a second channel 1032; the three-way valve 113 includes an inlet, a first channel 1131, and a second channel 1132.

[0020] For example, the air filter 101 is a device for filtering impurities and particulate matter in the air entering the fuel cell supply system, and its core component is the filter element. For example, the air filter 101 can use a dry or wet paper filter element to ensure that the air entering the subsequent system is clean and to avoid contamination or damage to precision components.

[0021] For example, the turbocharger 114 may include a turbine and a compressor, which are coaxially connected. Exhaust gas drives the turbine to rotate, which in turn drives the compressor to compress the intake air.

[0022] For example, the cathode inlet refers to the channel through which a treated oxidant, such as air, enters the fuel cell stack for reaction, and the cathode outlet refers to the channel through which exhaust gas after the reaction is completed is discharged from the fuel cell stack.

[0023] Along the air intake direction, the outlet of the air filter 101 is connected to a first branch and a second branch. The first branch of the air filter 101 is connected to the inlet of the three-way proportional valve 103, and the second branch of the air filter 101 is connected to the second channel 1032 of the three-way proportional valve 103 via the turbocharger 114. The first channel 1031 of the three-way proportional valve 103 is connected to the cathode inlet of the fuel cell stack 109 via the air compressor 105 to supply air to the fuel cell stack 109. The air intake direction refers to the path through which clean air is drawn in from the external environment and transported to the cathode inlet of the fuel cell stack for electrochemical reaction.

[0024] Along the exhaust direction, the cathode outlet of the fuel cell stack 109 is connected to the inlet of a three-way valve 113. The first channel 1131 of the three-way valve 113 is used for direct exhaust, and the second channel 1132 of the three-way valve 113 is used for exhaust via the turbocharger 114. "Along the exhaust direction" refers to the path of the exhaust gas after the reaction from the cathode outlet of the fuel cell stack until it is finally discharged to the outside.

[0025] In the above embodiments, under low-altitude, high-pressure conditions, air can enter through the first branch of the air filter 101 and the inlet of the three-way proportional valve 103, and exhaust gas is mainly discharged directly through the first channel 1131 of the three-way valve 113. At this time, the turbocharger 114 is not operating. Under high-altitude, low-pressure conditions, exhaust gas can be used entirely through the second channel 1132 of the three-way valve 113 to drive the turbocharger 114, pre-compressing the air from the second branch of the air filter 101. The pre-compressed air mixes proportionally with the low-pressure air from the first branch within the three-way proportional valve 103, thereby increasing the intake pressure before entering the high-power air compressor 105. This effectively reduces the pressure ratio required by the air compressor 105 under low-pressure conditions at high altitudes, keeping it away from the surge zone and making its operation more stable and reliable. Simultaneously, by recovering exhaust gas energy to drive the turbocharger 114, some compression work can be shared, thereby reducing the net power consumption of the air compressor 105, achieving the effect of improving system efficiency and reducing system power consumption.

[0026] In some embodiments, an intake flow meter 102 is provided at the outlet of the air filter 101. The intake flow meter 102 can be a sensor used to measure the total airflow through the outlet of the air filter. For example, the intake flow meter 102 can be a thermal mass flow meter or a vortex flow meter, providing the air supply system with an accurate intake volume signal for subsequent flow distribution and control.

[0027] The inlet of the three-way proportional valve 103 is used to receive unpressurized air from the air filter 101. The second channel 1032 of the three-way proportional valve 103 is connected to the compressor outlet of the turbocharger 114, and the second channel 1032 of the three-way proportional valve 103 is used to receive pressurized air from the compressor outlet of the turbocharger 114. In other words, the three-way proportional valve 103 is a hub that can mix low-pressure and high-pressure airflows.

[0028] The first channel 1031 of the three-way proportional valve 103 is used to output the mixed air. A first pressure sensor 104 is provided between the first channel 1031 of the three-way proportional valve 103 and the air compressor 105 to detect the air pressure at the outlet of the first channel 1031 of the three-way proportional valve 103, that is, at the inlet of the air compressor 105.

[0029] In some embodiments, a back pressure valve 112 is provided between the cathode outlet of the fuel cell stack 109 and the inlet of the three-way valve 113; the second channel 1132 of the three-way valve 113 is connected to the turbine inlet of the turbocharger 114. The back pressure valve 112 is an actuator for establishing and regulating the back pressure on the cathode outlet side of the fuel cell stack. For example, the back pressure valve 112 can be electrically or pneumatically regulated, precisely controlling the reaction pressure inside the fuel cell stack by changing its opening. The second channel 1132 of the three-way valve 113 is connected to the turbine inlet of the turbocharger 114, thus establishing a path for exhaust gas energy recovery. When the three-way valve 113 is switched to allow exhaust gas to flow through its second channel 1132, the exhaust gas will directly impact the turbine of the turbocharger 114 through this path, converting its contained energy into the rotational mechanical energy of the turbine, thereby driving the coaxial compressor. This allows for the recovery and reuse of previously wasted exhaust gas energy, providing pre-pressurization for the intake air and reducing the load on the air compressor 105, thus achieving energy savings. The back pressure valve 112, in conjunction with the turbine inlet of the turbocharger 114, enables the air supply system to independently and precisely control the cathode outlet pressure of the fuel cell stack in both direct exhaust and energy recovery modes. This ensures that the fuel cell stack always operates within the optimal pressure range without affecting the energy recovery function.

[0030] In some embodiments, an intercooler 106 and a shut-off valve 107 are sequentially arranged between the air compressor 105 and the cathode inlet of the fuel cell stack 109 along the air intake direction; a second pressure sensor 108 is arranged between the shut-off valve 107 and the cathode inlet of the fuel cell stack 109.

[0031] The gas supply system also includes a bypass branch, one end of which is connected to the pipeline between the intercooler 106 and the shut-off valve 107, and the other end is connected to the inlet of the three-way valve 113; the bypass branch is equipped with a bypass flow meter 110 and a bypass valve 111 in sequence.

[0032] When the first channel 1131 of the three-way valve 113 is open and the second channel 1132 is closed, the exhaust gas input into the inlet of the three-way valve 113 is directly discharged. In this case, no energy recovery is performed, making it suitable for low-altitude conditions or operating conditions with special requirements for exhaust back pressure. When the first channel 1131 of the three-way valve 113 is closed and the second channel 1132 is open, the exhaust gas input into the inlet of the three-way valve 113 is directed to the turbine of the turbocharger 114 to drive the turbocharger 114. In this case, the energy utilization of the exhaust gas is maximized, making it suitable for high-altitude conditions or operating conditions requiring high efficiency and energy saving.

[0033] For example, the intercooler 106 can be a heat exchanger used to reduce the temperature of the air compressed by the air compressor 105, preventing excessively hot air from entering the fuel cell stack, ensuring that the humidity and temperature of the fuel cell stack membrane electrode are within a suitable range, and simultaneously increasing the intake air density and oxygen mass flow rate. The shut-off valve 107 can be a valve installed in the pipeline for shutting off the gas supply system in the event of a shutdown or malfunction, thereby providing safety isolation.

[0034] For example, the second pressure sensor 108 can be used to directly detect the air pressure at the cathode inlet of the fuel cell stack. The pressure signal provided by the second pressure sensor 108 can be used for closed-loop control of the speed of the air compressor 105 and the opening of the back pressure valve 112 to determine whether the inlet pressure meets the requirements of the fuel cell stack.

[0035] For example, a bypass branch can allow a portion of compressed air to return directly to the exhaust side without passing through the fuel cell stack. A bypass flow meter 110 measures the airflow through this bypass branch. A bypass valve 111 can be an actuator that adjusts the flow cross-sectional area of ​​the bypass branch. The bypass branch allows for rapid adjustment of the compressor load during startup, load changes, or failures by opening the bypass valve, preventing surge; it also helps regulate the inflow air to the stack.

[0036] This specification provides a fuel cell gas supply method. Please refer to [link / reference]. Figure 2 , Figure 2 This is a flowchart illustrating a fuel cell gas supply method provided in this embodiment. This embodiment provides the method operation steps shown in the flowchart, but based on conventional or non-inventive methods, more or fewer operation steps may be included. The order of steps listed in this embodiment is merely one possible execution order among many, and does not represent the only possible execution order. In actual system or server product execution, the method can be executed sequentially or in parallel as shown in the embodiment. This fuel cell gas supply method can be applied to fuel cell gas supply systems, specifically as follows... Figure 2 As shown, the fuel cell gas supply method may include the following steps.

[0037] Step S210: Obtain atmospheric pressure.

[0038] Step S220: Determine the target gas supply mode based on atmospheric pressure; wherein, the target gas supply mode includes a low-altitude mode or a high-altitude mode.

[0039] Step S230: Supply gas to the fuel cell stack based on the target gas supply mode.

[0040] For example, atmospheric pressure can be read from the first pressure sensor 104 in the fuel cell gas supply system.

[0041] In some implementations, determining the target gas supply mode based on atmospheric pressure may include: if the atmospheric pressure is greater than or equal to a preset pressure threshold, the target gas supply mode adopts a low-altitude mode; otherwise, the target gas supply mode adopts a high-altitude mode.

[0042] For example, the preset pressure threshold can be a defined air pressure critical value used to distinguish between low-altitude and high-altitude environments. Based on this pressure threshold, the target gas supply mode can be switched, which directly affects the timing of the mode switch.

[0043] In some implementations, the preset pressure threshold is 90 kPa. The atmospheric pressure corresponding to 90 kPa corresponds to an altitude of approximately 1000 meters. This means that conditions below this altitude are considered low-altitude high-pressure environments, while conditions above this altitude are considered high-altitude low-pressure environments. It is understood that the preset pressure threshold can be determined based on actual conditions. For example, the atmospheric pressure corresponding to any altitude between 1000 and 1500 meters can be used as the pressure threshold to allow for flexible switching of the target gas supply mode.

[0044] In some implementations, please refer to Figure 3 Based on the target gas supply mode, gas supply to the fuel cell stack may include the following steps S310-S30.

[0045] Step S310: When the target air supply mode is low altitude mode, control the first channel of the three-way proportional valve to open and the second channel to close, so that all intake air from the air filter does not flow through the turbocharger.

[0046] Step S320: Control the first channel of the three-way valve to open and the second channel to close, so that all the exhaust gas entering through the three-way valve does not flow through the turbine of the turbocharger and is directly discharged.

[0047] Step S330: Based on the pressure and flow requirements at the cathode inlet of the fuel cell stack, control the speed of the air compressor and the opening of the back pressure valve in a closed loop.

[0048] In the above embodiments, under low-altitude mode, or in other words, under sufficient air pressure, the flow resistance caused by the turbocharger can be avoided, allowing the air supply system to operate along a simple and efficient traditional path. Secondly, by controlling the opening of the first channel and the closing of the second channel of the three-way valve, all exhaust gas entering through the three-way valve is discharged directly without flowing through the turbocharger's turbine. Corresponding to the aforementioned intake control, a complete low-altitude operating loop is formed. Exhaust gas does not drive the turbine, the system does not perform energy recovery, simplifying control and reducing exhaust back pressure.

[0049] In the above embodiments, the pressure and flow requirements can be target values ​​given by the host controller based on the power state of the fuel cell stack. Closed-loop control can use the actual inlet pressure detected by the second pressure sensor and the flow meter signal as feedback, and employ a proportional-integral (PI) controller to adjust the compressor speed in real time to control the flow rate and pressure ratio, while simultaneously adjusting the opening of the back pressure valve to precisely control the cathode-side pressure of the fuel cell stack. This ensures that, in low-altitude mode, while guaranteeing the fuel cell stack reaction requirements, the air supply system operates in its simplest and most reliable state, allowing the air compressor to operate within its high-efficiency range.

[0050] In some implementations, please refer to Figure 4 Based on the target gas supply mode, gas supply to the fuel cell stack may include the following steps S410-S440.

[0051] Step S410: When the target air supply mode is high altitude mode, control the second channel of the three-way valve to open and the first channel to close, so that all the exhaust gas entering through the three-way valve flows through the turbine of the turbocharger to provide driving force for the turbocharger.

[0052] Step S420: Based on the pressure demand at the cathode inlet of the fuel cell stack and the difference between it and the second pressure sensor in the fuel cell supply system, the proportional-integral controller is used as the input to obtain the opening command of the three-way proportional valve.

[0053] Step S430: Control the three-way proportional valve based on the opening command to adjust the mixing ratio of unpressurized air from the air filter to pressurized air from the turbocharger compressor; wherein, the opening command indicates the volume or mass flow rate ratio of the pressurized air from the turbocharger in the air flowing to the air compressor inlet.

[0054] Step S440: Based on the pressure and flow requirements at the cathode inlet of the fuel cell stack, control the speed of the air compressor and the opening of the back pressure valve in a closed loop.

[0055] In some implementations, when the target gas supply mode is a high-altitude mode, the pressure requirement at the cathode inlet of the fuel cell stack can be one standard atmosphere.

[0056] For example, assuming an altitude of 3650 meters and an atmospheric pressure of 64 kPa, the opening command output by the proportional-integral controller can be 0.68, meaning that 68% of the intake air flow comes from the turbocharged air and the remaining 32% comes from the unpressurized air from the air filter.

[0057] In the above embodiments, in high-altitude mode, or in other words, under conditions of insufficient air pressure, it can be ensured that all the energy of the exhaust gas is used to drive the turbine, thereby providing power to the compressor.

[0058] In the above embodiments, by dynamically adjusting the mixing ratio, the pressure of the mixed air entering the air compressor can be stabilized at a relatively high set value, such as close to standard atmospheric pressure, even though the ambient atmospheric pressure is very low. This reduces the pressure ratio that the air compressor needs to increase. Finally, based on the pressure and flow requirements of the cathode inlet of the fuel cell stack, the air compressor speed and the opening of the back pressure valve are controlled in a closed loop. Since the air compressor inlet pressure has been increased, its speed and power consumption are reduced. In this way, while ensuring the performance of the fuel cell stack, the energy of the exhaust gas can be utilized to the maximum extent, the load on the air compressor can be reduced, and the air supply system can operate efficiently and stably in high-altitude environments.

[0059] This specification also provides a vehicle that includes the fuel cell gas supply system described in any of the above embodiments.

[0060] It is understood that the specific examples in this document are only intended to help those skilled in the art better understand the embodiments described herein, and are not intended to limit the scope of the invention.

[0061] It is understood that in the various embodiments described in this specification, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments described in this specification.

[0062] It is understood that the various implementation methods described in this specification can be implemented individually or in combination, and the implementation methods in this specification are not limited in this respect.

[0063] Unless otherwise stated, all technical and scientific terms used in the embodiments of this specification have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this specification. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in the embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0064] It is understood that the processor in the embodiments of this specification can be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method embodiments can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this specification. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this specification can be directly implemented by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0065] It is understood that the memory in the embodiments of this specification may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may be random access memory (RAM). It should be noted that the memory in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0066] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this specification.

[0067] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the aforementioned method implementations, and will not be repeated here.

[0068] The above description is merely a specific embodiment of this specification, but the scope of protection of this invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this specification should be included within the scope of protection of this specification. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

Claims

1. A fuel cell gas supply system, characterized in that, The fuel cell stack includes an air filter, a turbocharger, a three-way proportional valve, an air compressor, a three-way valve, and a fuel cell; the fuel cell stack includes a cathode inlet and a cathode outlet; the three-way proportional valve includes an inlet, a first channel, and a second channel; the three-way valve includes an inlet, a first channel, and a second channel. Along the air intake direction, the outlet of the air filter is connected to a first branch and a second branch. The first branch of the air filter is connected to the inlet of the three-way proportional valve. The second branch of the air filter is connected to the second channel of the three-way proportional valve through the turbocharger. The first channel of the three-way proportional valve is connected to the cathode inlet of the fuel cell stack through the air compressor to supply air to the fuel cell stack. Along the exhaust direction, the cathode outlet of the fuel cell stack is connected to the inlet of the three-way valve. The first channel of the three-way valve is used for direct exhaust, and the second channel of the three-way valve is used for exhaust through the turbocharger.

2. The gas supply system according to claim 1, characterized in that, An air flow meter is installed at the outlet of the air filter; The inlet of the three-way proportional valve is used to receive unpressurized air from the air filter; The second channel of the three-way proportional valve is connected to the compressor outlet of the turbocharger, and the second channel of the three-way proportional valve is used to receive pressurized air from the compressor outlet of the turbocharger. A first pressure sensor is provided between the first channel of the three-way proportional valve and the air compressor. The first channel of the three-way proportional valve is used to output the mixed air.

3. The gas supply system according to claim 1, characterized in that, A back pressure valve is provided between the cathode outlet of the fuel cell stack and the inlet of the three-way valve; the second channel of the three-way valve is connected to the turbine inlet of the turbocharger.

4. The gas supply system according to claim 1, characterized in that, Along the air intake direction, an intercooler and a shut-off valve are sequentially arranged between the air compressor and the cathode inlet of the fuel cell stack; a second pressure sensor is arranged between the shut-off valve and the cathode inlet of the fuel cell stack. The gas supply system also includes a bypass branch, one end of which is connected to the pipeline between the intercooler and the shut-off valve, and the other end is connected to the inlet of the three-way valve; the bypass branch is equipped with a bypass flow meter and a bypass valve in sequence. When the first channel of the three-way valve is open and the second channel is closed, it is used to directly discharge the waste gas input into the inlet of the three-way valve. When the first channel of the three-way valve is closed and the second channel is open, it is used to direct the exhaust gas input into the inlet of the three-way valve to the turbine of the turbocharger, thereby driving the turbocharger.

5. A fuel cell gas supply method, characterized in that, The gas supply method, applied to a fuel cell gas supply system as described in any one of claims 1 to 4, comprises: Obtain atmospheric pressure; Based on the atmospheric pressure, a target gas supply mode is determined; wherein, the target gas supply mode includes a low-altitude mode or a high-altitude mode. Gas is supplied to the fuel cell stack based on the target gas supply mode.

6. The gas supply method according to claim 5, characterized in that, The determination of the target gas supply mode based on the atmospheric pressure includes: If the atmospheric pressure is greater than or equal to a preset pressure threshold, the target gas supply mode adopts the low-altitude mode; otherwise, the target gas supply mode adopts the high-altitude mode. The atmospheric pressure is read from the first pressure sensor in the fuel cell gas supply system.

7. The gas supply method according to claim 6, characterized in that, The preset pressure threshold is 90 kPa.

8. The gas supply method according to claim 5, characterized in that, The step of supplying gas to the fuel cell stack based on the target gas supply mode includes: When the target air supply mode is the low altitude mode, the first channel of the three-way proportional valve is opened and the second channel is closed, so that all the intake air from the air filter does not flow through the turbocharger. The first channel of the three-way valve is opened and the second channel is closed, so that all the exhaust gas entering through the three-way valve does not flow through the turbine of the turbocharger and is directly discharged. Based on the pressure and flow requirements at the cathode inlet of the fuel cell stack, the speed of the air compressor and the opening of the back pressure valve are controlled in a closed loop.

9. The gas supply method according to claim 5, characterized in that, The step of supplying gas to the fuel cell stack based on the target gas supply mode includes: When the target air supply mode is the high-altitude mode, the second channel of the three-way valve is opened and the first channel is closed, so that all the exhaust gas entering through the three-way valve flows through the turbine of the turbocharger to provide driving force for the turbocharger; The pressure requirement at the cathode inlet of the fuel cell stack and the difference between the pressure and the second pressure sensor in the fuel cell supply system are used as inputs to the proportional-integral controller to obtain the opening command of the three-way proportional valve. The three-way proportional valve is controlled based on the opening command to adjust the mixing ratio of unpressurized air from the air filter to pressurized air from the turbocharger compressor; wherein the opening command indicates the volume or mass flow rate ratio of the pressurized air from the turbocharger in the air flowing to the air compressor inlet. Based on the pressure and flow requirements at the cathode inlet of the fuel cell stack, the speed of the air compressor and the opening of the back pressure valve are controlled in a closed loop.

10. The gas supply method according to claim 9, characterized in that, When the target gas supply mode is the high-altitude mode, the pressure requirement at the cathode inlet of the fuel cell stack is one standard atmosphere.

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