Fuel cell system and control method thereof

Abstract

The embodiment of the invention relates to a fuel cell system and a control method thereof. The control method includes determining a generation rate of liquid water at a humidifier in a fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack in the fuel cell system. The control method further includes adjusting an opening in a bypass valve of a second channel based at least on the rate of formation of liquid water, the second channel being connected to the cathode inlet as a bypass to the first channel. On the basis of the mode, the risk that condensed water accumulated in the humidifier of the fuel cell system is brought into the electric pile to cause water logging shutdown can be reduced, so that the stability and the reliability of the fuel cell system are improved.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to the field of battery technology, and more particularly, to a fuel cell system, a control method of the fuel cell system, a controller, a control device, and a computer-readable storage medium. Background Art

[0002] A fuel cell is a chemical device that converts the chemical energy of a fuel directly into electrical energy. It has the characteristics of low pollution and high efficiency, and is a promising power generation technology. A typical fuel cell system (e.g., a proton exchange membrane fuel cell (PEMFC)) includes a hydrogen system that supplies hydrogen, a cathode system that supplies humid air, a thermal system that controls the temperature of the stack, and an electrical system that obtains current.

[0003] The technical challenges related to performance and durability of fuel cell systems are closely related to the health of the hydration reaction. The proton conductivity of the membrane depends largely on its hydration rate. In order to ensure good membrane ion conductivity and achieve good water management inside the stack, a humidifier is used to humidify the air entering the stack, which, however, brings the risk of flooding the stack. Summary of the invention

[0004] In view of this, the embodiments of the present disclosure provide a control method for a fuel cell system, a fuel cell system, a controller, a control device, and a computer-readable storage medium. The embodiments of the present disclosure can reduce the risk of condensed water accumulated in a humidifier of the fuel cell system being brought into the fuel cell stack, resulting in water flooding and shutdown, thereby improving the stability and reliability of the fuel cell system.

[0005] According to a first aspect of the present disclosure, a control method for a fuel cell system is provided. The method includes: determining a generation rate of liquid water at a humidifier in the fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack in the fuel cell system; and adjusting an opening of a bypass valve in a second channel, the second channel being connected to the cathode inlet as a bypass of the first channel, based at least on the generation rate of the liquid water.

[0006] According to a second aspect of the present disclosure, a fuel cell system is provided. The fuel cell system includes: a stack; a humidifier located in a first channel connected to a cathode inlet of the stack; a bypass valve located in a second channel connected to the cathode inlet as a bypass of the first channel; and a controller. The controller is configured to: determine a generation rate of liquid water at the humidifier; and adjust an opening of the bypass valve based at least on the generation rate of liquid water.

[0007] According to a third aspect of the present disclosure, a controller is provided, comprising: a processing unit; and a memory, the memory being coupled to the processing unit and storing instructions for execution by the processing unit, the instructions, when executed by the processing unit, causing the controller to execute a method, the method comprising: determining a generation rate of liquid water at a humidifier of a fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack of the fuel cell system; adjusting an opening of a bypass valve in a second channel based at least on the generation rate of liquid water, the second channel being connected to the cathode inlet as a bypass of the first channel.

[0008] According to a fourth aspect of the present disclosure, a control device for a fuel cell system is provided. The device includes: a determination unit configured to determine a generation rate of liquid water at a humidifier in the fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack in the fuel cell system; and an adjustment unit configured to adjust an opening of a bypass valve in a second channel, the second channel being connected to the cathode inlet as a bypass of the first channel, based at least on the generation rate of the liquid water.

[0009] According to a fifth aspect of the present disclosure, there is provided a computer-readable storage medium, comprising machine-executable instructions, which, when executed by a device, cause the device to perform the method according to the first aspect of the present disclosure.

[0010] This summary is provided to introduce a selection of concepts in a simplified form, which will be further described in the following detailed description. This summary is not intended to identify key features or essential features of the present disclosure, nor is it intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0012] Figure 1 shows a schematic block diagram of a fuel cell system according to some embodiments of the present disclosure;

[0013] Figure 2 A schematic flow chart showing a control method of a fuel cell system according to some embodiments of the present disclosure is shown;

[0014] Figure 3 shows a detailed schematic diagram of a fuel cell system according to some embodiments of the present disclosure;

[0015] Figure 4 shows a detailed schematic diagram of a control method according to some embodiments of the present disclosure;

[0016] Figure 5 A schematic block diagram showing a control device according to some embodiments of the present disclosure; and

[0017] Figure 6 Schematic block diagrams of example devices that can be used to implement embodiments of the present disclosure are shown. DETAILED DESCRIPTION

[0018] It is understandable that the data involved in this technical solution (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of relevant laws, regulations and relevant provisions.

[0019] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0020] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0021] It should be noted that the numbers or numerical values ​​used in this document are intended to facilitate understanding of the technology of the present disclosure, rather than to limit the scope of the present disclosure.

[0022] As mentioned above, in the fuel cell system, in order to ensure good membrane ion conductivity and achieve good internal water management of the stack, a humidifier is used to humidify the air entering the stack. For the humidity of the air entering the stack, the ratio of dry and wet air entering the stack is adjusted by controlling the humidifier bypass valve and the humidifier stop valve, thereby controlling the humidity of the air entering the stack. In some implementations, the position of the bypass valve and the stop valve of the humidifier, that is, the opening, can be set based on the humidity requirements of the stack during operation, based on the current set point and the air humidity before the humidifier. However, when the ambient temperature is low and the temperature of each component is low, during the system cold machine start idle warm-up process, when the hot air obtained through the air compressor and the intercooler passes through the cold humidifier, condensation will occur, and liquid water will accumulate in the humidifier. With the subsequent power increase, the air flow increases, and the accumulated liquid water will be brought into the stack, causing the stack to be flooded and shut down.

[0023] On the other hand, even recalibrating the bypass valve and the shut-off valve is difficult to solve this problem. When the system is just started, the current is small and the amount of water generated by the stack is small. If a smaller humidification level is calibrated, it cannot meet the self-humidification requirements. However, calibrating a larger humidification level will cause frequent flooding of the stack.

[0024] In view of this, an embodiment of the present disclosure provides a control method for a fuel cell system. In the control method, a controller can determine the rate of generation of liquid water at a humidifier, and adjust the opening of a bypass valve located in a humidifier bypass based at least on the determined rate of generation of liquid water. In this way, the controller can dynamically adjust the opening of the bypass valve of the humidifier, thereby controlling the rate of generation of liquid water at the humidifier, and preventing the liquid water accumulated at the humidifier from being brought into the fuel cell stack, causing the system to shut down.

[0025] The following references Figures 1 to 6 Detailed description of implementation details of the embodiments of the present disclosure.

[0026] Figure 1 1 shows a schematic block diagram of a fuel cell system 100 according to some embodiments of the present disclosure. It should be understood that Figure 1 The fuel cell system 100 shown is merely exemplary and should not constitute any limitation on the functionality and scope of the implementation described in the present disclosure. Figure 1 As shown, the fuel cell system 100 includes a controller 150, a humidifier 110, a bypass valve 120, and a fuel cell stack 130. The controller 150 may be any type of electronic device with computing capabilities, which may receive data from various types of sensors (not shown) of the fuel cell system 100, and generate control commands as outputs for controlling the components of the fuel cell system 100 by running computer programs or instructions.

[0027] The humidifier 110 is located in the first channel 115 connected to the cathode inlet of the battery stack, and is used to humidify the passing air and provide humidified air. Figure 1 As shown, the fuel cell system 100 further includes a second channel 125 as a bypass of the first channel 115. A bypass valve 120 is provided in the second channel 125. The second channel 125 provides unhumidified air. The humidified air from the first channel 115 and the unhumidified air from the second channel 125 are mixed and enter the stack 130 to participate in the electrochemical reaction in the stack 130.

[0028] The controller 120 can control the opening of the bypass valve 120 to control the ratio of the air flow entering the first channel 115 and the second channel 125. For example, the opening of the bypass valve 120 is increased to increase the flow of unhumidified air and reduce the humidity of the mixed air entering the stack 130. Similarly, the opening of the bypass valve can be reduced to increase the humidity of the mixed air entering the stack 130.

[0029] It should be noted that Figure 1 The fuel cell system 100 is merely illustrative, and the fuel cell system according to the embodiment of the present disclosure may include more or fewer components, such as sensors, bypass valves, shutoff valves, channels, etc. The present disclosure is not limited in this respect.

[0030] Figure 2 FIG. 2 is a schematic flow chart of a control method 200 for a fuel cell system according to some embodiments of the present disclosure. The control method 200 may be Figure 1 For convenience of explanation, the controller 150 shown in FIG. Figure 1 The control method 200 will be described.

[0031] At 210, the controller 150 determines the generation rate of liquid water at the humidifier 110 in the fuel cell system 100. As mentioned above, the formation of liquid water is caused by condensation, and if it is brought into the fuel cell stack 130 by air, it will cause flooding and shutdown. In general, the controller 100 can calculate the generation rate of liquid water at the humidifier 110 based on the mass flow rate of water vapor in the air entering the humidifier 110, the mass flow rate of water vapor introduced by penetration of the humidifier 110, and the mass flow rate of water vapor in the air leaving the humidifier 110, using the law of conservation of mass.

[0032] In some embodiments, the controller 150 may calculate the sum of the first flow rate of water vapor at the inlet of the humidifier 110 and the second flow rate of water vapor permeating the humidifier, and then subtract the third flow rate at the outlet of the humidifier 110 to obtain the generation rate of liquid water accumulated in the humidifier 110. The controller 150 may calculate the first flow rate, the second flow rate, and the third flow rate based on sensor data on temperature, pressure, flow rate, etc. in the fuel cell system 100. Figure 3 Further description.

[0033] At 220, the controller 150 adjusts the opening of the bypass valve 120 in the second passage 125 based at least on the rate of generation of the liquid water. Figure 1, the first channel 115 provides humidified air, and the second channel 125 serves as a bypass channel of the humidifier 110 to provide unhumidified air. The opening of the bypass valve 120 can affect the distribution ratio of the air flow between the first channel 115 and the second channel 125. If the rate of generation of liquid water is higher than a predetermined threshold, this indicates that there is a high risk of flooding of the stack 130. At this time, the controller 150 can increase the opening of the bypass valve 120, increase the proportion of unhumidified air flowing through the second channel 125, and reduce the rate of generation of liquid water at the humidifier in the first channel, thereby reducing the risk of flooding of the stack 130. If the rate of generation of liquid water is lower than a predetermined threshold (different from the threshold that triggers the increase in the opening of the bypass valve), this indicates a low risk of flooding of the stack 130. At this time, the controller 150 can reduce the opening of the bypass valve 120, increase the proportion of humidified air flowing through the first channel 115, and improve the performance and efficiency of the electrochemical reaction of the stack 130.

[0034] Figure 3 A detailed schematic diagram of a fuel cell system 300 is shown according to some embodiments of the present disclosure. Figure 3 The fuel cell 300 shown may be Figure 1 The fuel cell system 100 is an exemplary embodiment of the present invention. As shown in the figure, the fuel cell system 300 includes a controller 350, a humidifier 310 located in the first channel 315, a bypass valve 320 located in the second channel 325, and a fuel cell stack 330. These components are similar to those in the reference Figure 1 The corresponding components described are similar and will not be described in detail here.

[0035] The fuel cell system 300 also includes an air filter 301, a sensor 302, an air compressor (EAC) 303, and an intercooler 304 along the air intake direction. The sensor 302 can collect the temperature, pressure, mass flow rate, and humidity of the air flowing through here. The air flowing out of the intercooler 304 is divided into three channels at the connection point 305: a first channel 315 passing through the humidifier 110, a second channel 325 bypassing the humidifier 110 and entering the stack 330, and a third channel 335 bypassing the humidifier 110 and the stack 330. The third channel 335 is provided with a sensor 306 and a bypass valve 307. The sensor 306 can collect information such as the mass flow rate of the air flowing through here.

[0036] In some implementations, the connection point 305 can be implemented as, for example, a four-way valve. The connection point 305 is located upstream of the first channels 315 and 325, and for ease of understanding, it may also be referred to herein as the upstream connection point 305. A shutoff valve 322 is also provided downstream of the humidifier 110 in the first channel 315. The shutoff valve 322 and the bypass valve can be changed in opening degree under the control of the controller 150, and operate in coordination to control the ratio of the flow rate of air entering the first channel 315 and the second channel 325 from the upstream connection point 305.

[0037] The fuel cell system 300 also includes a temperature sensor 308 and a pressure sensor 309 located at the cathode inlet of the stack 130. In some implementations, the positions of the two are interchangeable and can be integrated together. The temperature sensor 308 and the pressure sensor 309 are used to detect the temperature and pressure at the cathode inlet, respectively. The fuel cell system 300 also includes a shut-off valve 332 located near the outlet of the stack 330, and a backup pressure regulating valve 334.

[0038] Figure 4 Detailed schematic diagram of a control method 400 according to some embodiments of the present disclosure is shown. The control method 400 may be performed by a controller of a fuel cell system (eg, Figure 1 The controller 150 and Figure 3 For convenience of explanation, refer to Figure 3 Method 400 is described.

[0039] In general, the controller inputs include the temperature, pressure, mass flow and humidity at the sensor 302 located after the air filter 301, the temperature, pressure and mass flow at the sensor 306 located after the intercooler 304, and the temperature and pressure from the temperature sensor 308 and the pressure sensor 309 at the cathode inlet of the stack. The output of the controller is the corrected opening of the bypass valve 320, and in some implementations, the opening of the shut-off valve 322 may also be corrected.

[0040] refer to Figure 4 At box 410 , the control method 400 starts. As the fuel cell system starts, the method 400 proceeds to 402 , where the controller 350 reads the collected values ​​of the sensors 302 , 306 , 308 , and 309 in the fuel cell system 300 .

[0041] The ambient air includes dry air (oxygen and nitrogen) and water vapor. At 403 , the controller calculates the mass flow rate m_dot_Vap_1 of water vapor in the intake air based on the temperature, pressure, mass flow rate and humidity provided by the sensor 302 and the principle of thermodynamics, thereby obtaining the mass fraction x_Vap of water vapor in the air before entering the intercooler 304 .

[0042] refer to Figure 3 , the temperature of the air passing through the air compressor 303 and the intercooler 304 will not be lower than the ambient temperature, which means that the air will not condense during this process. Therefore, the mass flow rate of water vapor in the air after the intercooler 304 is still m_dot_Vap_1. At 404, the controller 350 calculates the mass flow rate m_dot_Vap_Hum_In of water vapor before the air enters the humidifier 310. Specifically, the controller 350 determines the total air flow rate of the air entering the first channel 315 (i.e., entering the humidifier 310) and the air entering the second channel 325 based on the mass flow rate feedback from the sensor 302 and the mass flow rate feedback from the sensor 306. The controller 350 can estimate the air flow rate m_dot_hum entering the humidifier based on the opening of the bypass valve 320 and the stop valve 322. It should be noted that according to the law of conservation of mass, the mass fraction of water vapor here is still x_Vap. Thus, the mass flow rate m_dot_Vap_Hum_In of water vapor before entering the humidifier 310 can be obtained.

[0043] At 405 , the controller 350 may obtain the mass flow rate m_dot_Hum_Trans of water vapor permeating from the humidifier in the current state based on the humidifier performance characteristic curve.

[0044] At 406, the controller 350 estimates the air flow rate m_dot_hum entering the humidifier. At 407, the controller 350 determines the mass flow rate of water vapor at the humidifier outlet. Assuming that the relative humidity of the air passing through the humidifier 310 is 100%, that is, saturated, the mass flow rate m_dot_Vap_Hum_Out of the water vapor at the humidifier outlet can be determined based on the temperature and pressure at the cathode inlet fed back by sensors 308 and 309. Specifically, the saturated vapor pressure P_Sat is a function of the cathode inlet temperature (308), and the water vapor pressure at the humidifier outlet can be obtained as P_Vap_Hum_Out=P_Sat*100%. In addition, based on the mass flow rate m_dot_Vap_Hum_In of water vapor obtained in step 404, the mass flow rate P_DryAir_Hum_in of dry air can be calculated, that is, the total mass flow rate minus m_dot_Vap_Hum_In. The mass flow rate of water vapor at the humidifier outlet m_dot_Vap_Hum_Out can be calculated according to the following equation:

[0045] m_dot_Vap_Hum_Out / m_dot_dry_hum_Out=

[0046] (M_Vap*P_Vap_Hum_Out) / (M_DryAir*P_DryAir_Hum_Out)(1)wherein P-DryAir_Hum_Out=P_Stack_In-P_Vap_Hum_Out, P_Stack_In is the pressure value of the pressure sensor 309, m_dot_dry_hum_Out is the mass flow rate of dry air at the humidifier outlet, M_Vap is the molar mass of water vapor, M_DryAir is the molar mass of dry air, and P_DryAir_Hum_Out is the partial pressure of dry air at the humidifier outlet.

[0047] At 408, the controller 350 determines the generation rate of liquid water at the humidifier 310. The controller 350 may calculate the generation rate according to the following equation: m_dot_Liq = m_dot_Vap_Hum_In + m_dot_hum_Trans - m_dot_Vap_Hum_Out.

[0048] At 409, the controller 350 may perform a table lookup based on the calculated generation rate and the air flow m_dot_hum entering the humidifier. At 410, based on the table lookup result, determine whether the bypass valve needs to be corrected. If correction is required, at 411, the opening of the bypass valve 320 is increased. For example, when the air flow is less than the first threshold and the generation rate is greater than the second threshold, the opening of the bypass valve 320 can be increased to reduce the generation rate of condensed water. Otherwise, return to 402, the controller 350 may not make corrections and control the opening of the bypass valve 320 according to the original set value. In order to avoid frequent corrections, the controller 350 may start a timer with a predetermined time after adjusting the opening. Within the predetermined time, the controller 350 maintains the adjusted opening. At 412, the controller 350 increments the timer. At 413, determine whether the timer has reached the predetermined time. If not, return to 412 and increment the timer. If the predetermined time is reached, the control method 400 returns to 402 and repeats the actions from 402 to 413 to re-determine the opening of the bypass valve 320. Finally, when the system is shut down, at 414, the control method 400 ends.

[0049] References Figures 1 to 4 The present invention describes a fuel cell system and a control method thereof according to an embodiment of the present invention. Compared with a conventional fuel cell system, the embodiment of the present invention can reduce the risk of condensed water accumulated in a humidifier of the fuel cell system being brought into the fuel cell stack, causing water flooding and shutdown, thereby improving the stability and reliability of the fuel cell system.

[0050] Figure 5A schematic block diagram of a control device 500 according to some embodiments of the present disclosure is shown. The control device 500 may be arranged at the controllers 150 and 350. As shown, the control device 500 includes a determination unit 510 and an adjustment unit 520. The determination unit 510 is configured to determine the generation rate of liquid water at a humidifier in a fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack in the fuel cell system. The adjustment unit 520 is configured to adjust the opening of a bypass valve in a second channel, the second channel being connected to the cathode inlet as a bypass of the first channel, based at least on the generation rate of liquid water.

[0051] In some embodiments, the determination unit 510 can also be configured to: determine a first flow rate of water vapor at the inlet of the humidifier; determine a second flow rate of water vapor permeating the humidifier; determine a third flow rate of water vapor at the outlet of the humidifier; and determine a liquid water generation rate based on the first flow rate, the second flow rate and the third flow rate.

[0052] In some embodiments, the determination unit 510 can also be configured to: determine the air flow at the inlet of the humidifier based on the opening of the bypass valve and the shut-off valve in the first channel, and the total air flow of the first channel and the second channel; and determine the first flow of water vapor based on the air flow at the inlet of the humidifier and the water vapor fraction.

[0053] In some embodiments, the first channel and the second channel have an upstream connection point. The determination unit 510 may also be configured to determine the water vapor fraction by detecting the temperature, pressure, flow rate and humidity of the air before the upstream connection point.

[0054] In some embodiments, the determination unit 510 can also be configured to: detect the air flow of the third channel that bypasses the battery stack and the humidifier at the upstream connection point; and determine the total air flow of the first channel and the second channel based on the air flow of the third channel and the air flow before the upstream connection point.

[0055] In some embodiments, the second flow rate of water vapor may be derived based on a performance characteristic curve of the humidifier.

[0056] In some embodiments, the determination unit 510 may be further configured to determine a third flow rate of water vapor based on the temperature and pressure at the cathode inlet and the air flow rate at the inlet of the humidifier.

[0057] In some embodiments, the adjustment unit 520 may be further configured to adjust the opening of the bypass valve based on the air flow rate at the inlet of the humidifier and the generation rate of liquid water.

[0058] In some embodiments, the adjustment unit 520 may be further configured to increase the opening of the bypass valve in response to the air flow at the inlet of the humidifier being less than a first threshold and the generation rate of liquid water being greater than a second threshold.

[0059] In some embodiments, the adjustment unit 520 may be further configured to: maintain the adjusted opening of the bypass valve within a predetermined time after the adjustment; and re-determine the opening of the bypass valve after the predetermined time is reached.

[0060] Figure 6 A schematic block diagram of an example device 600 that can be used to implement an embodiment of the present disclosure is shown. For example, the control method, controller 150 and 350 of the fuel cell system according to the embodiment of the present disclosure can be implemented by the device 600. As shown in the figure, the device 600 includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) 602 or computer program instructions loaded from a 600 storage unit 608 to a random access memory (RAM) 603. In RAM 603, various programs and data required for the operation of the device 600 can also be stored. CPU 601, ROM 602 and RAM 603 are connected to each other via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0061] Multiple components in the device 600 are connected to the I / O interface 605. The types of I / O interfaces include, but are not limited to, peripheral component interconnect (PCIe), universal serial bus (USB), high-definition multimedia interface (HDMI), serial connection (SAS), etc. The components based on the I / O interface 605 may include, but are not limited to: input unit 606, such as keyboard, mouse, etc.; output unit 607, such as respective types of display, speaker, etc.; storage unit 608, such as disk, optical disk, etc.; and communication unit 609, such as network adapter, modem, wireless communication transceiver, etc. The communication unit 609 allows the device 600 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0062] The various processes and processing described above, such as processes 200, 400, and / or 500, may be performed by a processing unit in the device 600, such as the processing unit 601 and / or other processing units (e.g., a microprocessor on a mainboard of the device 600). For example, in some embodiments, the method processes 200 and / or 400 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 608. In some embodiments, part or all of the computer program may be loaded and / or installed on the device 600 via the ROM 602 and / or the communication unit 609. When the computer program is loaded into the RAM 603 and executed, one or more actions of the processes 200 and / or 400 described above may be performed.

[0063] The present disclosure may be a method, an apparatus, a system and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing various aspects of the present disclosure.

[0064] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0065] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0066] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0067] Various aspects of the present disclosure are described herein with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer-readable program instructions.

[0068] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processing unit of the computer or other programmable data processing device, a device that implements the functions / actions specified in one or more boxes in the flowchart and / or block diagram is generated. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause the computer, programmable data processing device, and / or other equipment to work in a specific manner, so that the computer-readable medium storing the instructions includes a manufactured product, which includes instructions for implementing various aspects of the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0069] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operating steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0070] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of the module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0071] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A control method for a fuel cell system, comprising: determining a rate of liquid water generation at a humidifier in the fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a fuel cell stack in the fuel cell system; Based at least on the generation rate of the liquid water, an opening degree of a bypass valve in a second passage connected to the cathode inlet as a bypass of the first passage is adjusted.

2. The method of claim 1 , wherein determining a rate of generation of liquid water at a humidifier of the fuel cell system comprises: determining a first flow rate of water vapor at an inlet of the humidifier; determining a second flow rate of water vapor permeating the humidifier; determining a third flow rate of water vapor at an outlet of the humidifier; as well as A generation rate of the liquid water is determined based on the first flow rate, the second flow rate, and the third flow rate.

3. The method of claim 2, wherein determining a first flow rate of water vapor at an inlet of the humidifier comprises: determining an air flow rate at an inlet of the humidifier based on the openings of the bypass valve and the shutoff valve in the first passage, and the total air flow rate of the first passage and the second passage; as well as The first flow rate of water vapor is determined based on the air flow rate and the water vapor fraction at the inlet of the humidifier.

4. The method of claim 3, wherein the first channel and the second channel have an upstream connection point, the method further comprising: The water vapor fraction is determined by detecting the temperature, pressure, flow rate and humidity of the air before the upstream connection point.

5. The method according to claim 4, further comprising: detecting an air flow rate of a third passage bypassing the fuel cell stack and the humidifier from the upstream connection point; as well as The total air flow rate of the first passage and the second passage is determined based on the air flow rate of the third passage and the air flow rate before the upstream connection point. The method according to claim 2 , wherein the second flow rate of water vapor is obtained based on a performance characteristic curve of the humidifier.

7. The method of claim 2, wherein determining a third flow rate of water vapor at an outlet of the humidifier comprises: The third flow rate of the water vapor is determined based on the temperature and pressure at the cathode inlet and the air flow rate at the inlet of the humidifier.

8. The method of claim 1, wherein adjusting the opening of the bypass valve in the second passage comprises: The opening in the bypass valve is adjusted based on the air flow rate at the inlet of the humidifier and the generation rate of the liquid water.

9. The method according to claim 8, wherein adjusting the opening of the bypass valve comprises: In response to the air flow rate at the inlet of the humidifier being less than a first threshold and the generation rate of the liquid water being greater than a second threshold, the opening degree of the bypass valve is increased.

10. The method according to claim 1, further comprising: maintaining the adjusted opening of the bypass valve within a predetermined time after the adjustment; as well as After the predetermined time has elapsed, the opening degree of the bypass valve is re-determined.

11. The method according to claim 1, wherein the fuel cell system further comprises: an air filter, a sensor, an air compressor and an intercooler located upstream of the first channel and the second channel, and a stop valve located in the first passage; as well as A bypass valve and a sensor are located in a third channel that bypasses the stack and the humidifier.

12. A fuel cell system comprising: Battery stack; a humidifier located in a first channel connected to a cathode inlet of the stack; a bypass valve located in a second passage connected to the cathode inlet as a bypass of the first passage; as well as The controller is configured as: determining a rate of liquid water generation at the humidifier; as well as At least based on said generation of said liquid water The rate adjusts the opening of the bypass valve.

13. A controller comprising: Processing unit; and a memory coupled to the processing unit and storing instructions for execution by the processing unit, the instructions, when executed by the processing unit, causing the controller to perform a method comprising: determining a rate of liquid water generation at a humidifier of a fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a stack of the fuel cell system; Based at least on the generation rate of the liquid water, an opening degree of a bypass valve in a second passage connected to the cathode inlet as a bypass of the first passage is adjusted.

14. A control device for a fuel cell system, comprising: a determination unit configured to determine a generation rate of liquid water at a humidifier in the fuel cell system, wherein the humidifier is located in a first channel connected to a cathode inlet of a fuel cell stack in the fuel cell system; as well as An adjustment unit is configured to adjust an opening degree of a bypass valve in a second channel connected to the cathode inlet as a bypass of the first channel based at least on the generation rate of the liquid water.

15. A computer-readable storage medium comprising machine-executable instructions which, when executed by a device, cause the device to perform the method according to any one of claims 1 to 11.

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