Fuel cell humidity control method and device, electronic equipment and storage medium

Abstract

The invention relates to a fuel cell humidity control method and device, electronic equipment and a storage medium, and the method comprises the steps: starting an on-load purging program when a power system of a fuel cell is ready to stop; wherein the on-load purging program is used for providing a predetermined flow of airflow for the fuel cell stack and purging the interior of the fuel cell stack; the method comprises the following steps: when an on-load purging program is started, injecting a sinusoidal current signal with a set frequency into a DC-DC converter connected with a fuel cell stack as current disturbance so as to induce an electrochemical impedance spectroscopy (EIS) response; in the injection current disturbance process of the DC-DC converter, the actual EIS amplitude of EIS response under the set frequency is determined; and controlling the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude. The method not only can save the downtime, but also can improve the operation reliability of the fuel cell power system.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell humidity control method, a control device, an electronic device and a storage medium. Background Art

[0002] In the field of fuel cell technology, the stable operation of the power system is highly dependent on the precise control of the humidity of the fuel cell stack. However, this key parameter faces the difficulty of direct monitoring, that is, it cannot be intuitively characterized by conventional sensors. Especially during the shutdown phase of the fuel cell, the management of internal humidity becomes particularly critical and challenging, because it is directly related to the stability of the fuel cell stack voltage when the power system is restarted. Especially under low temperature environmental conditions, the humidity state during shutdown has a more significant impact on the starting performance, which may lead to adverse consequences such as insufficient voltage and difficulty in starting. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, the first object of the present invention is to propose a fuel cell humidity control method. The method adds an EIS detection function to continuously inject current disturbances of a set frequency into a DC-DC (Direct Current to Direct Current) converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

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

[0006] A third objective of the present invention is to provide an electronic device.

[0007] A fourth object of the present invention is to provide a computer-readable storage medium.

[0008] A fifth object of the present invention is to provide a computer program product.

[0009] To achieve the above-mentioned purpose, a first aspect of the present invention proposes a fuel cell humidity control method, comprising: when the power system of the fuel cell is ready to shut down, starting an on-load purge program; wherein the on-load purge program is used to provide a predetermined flow rate of airflow to the fuel cell stack to purge the inside of the fuel cell stack; when the on-load purge program is started, a sinusoidal current signal of a set frequency is injected into a DC-DC converter connected to the fuel cell stack as a current disturbance to induce an electrochemical impedance spectroscopy (EIS) response; during the process of injecting the current disturbance into the DC-DC converter, the actual EIS amplitude of the EIS response at the set frequency is determined; and according to the actual EIS amplitude, the internal humidity of the fuel cell after shutdown is controlled.

[0010] According to the fuel cell humidity control method of the embodiment of the present invention, when the power system of the fuel cell is ready to shut down, the on-load purge program is started. When the on-load purge program is started, a sinusoidal current signal of a set frequency is injected into the DC-DC converter connected to the fuel cell stack as a current disturbance to induce an electrochemical impedance spectroscopy EIS response. During the process of injecting current disturbance into the DC-DC converter, the actual EIS amplitude of the EIS response at the set frequency is determined, and the internal humidity of the fuel cell after the shutdown is controlled according to the actual EIS amplitude. Therefore, the method continuously injects a current disturbance of a set frequency into the DC-DC converter during the shutdown of the power system of the fuel cell by adding an EIS detection function, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after the shutdown is controlled according to the EIS amplitude, which can not only save downtime, but also improve the operational reliability of the fuel cell power system.

[0011] In addition, the fuel cell humidity control method provided in the first embodiment of the present invention may also have the following additional technical features:

[0012] In one embodiment of the present invention, the controlling of the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude includes:

[0013] Predetermining a target humidity that the fuel cell stack needs to reach when shutting down;

[0014] Determining a target EIS amplitude according to the target humidity;

[0015] The actual EIS amplitude is compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the on-load purge procedure is stopped and the injection of the current disturbance into the DC-DC converter is stopped at the same time to complete the control of the internal humidity of the fuel cell after shutdown.

[0016] In one embodiment of the present invention, determining a target EIS amplitude according to the target humidity includes:

[0017] Pre-establishing a first corresponding relationship between internal resistance and humidity, and a second corresponding relationship between EIS amplitude and internal resistance of the fuel cell stack under different shutdown conditions;

[0018] When the power system of the fuel cell is ready to shut down, obtaining current shutdown operating condition information;

[0019] According to the acquired current shutdown condition information and the target humidity, the corresponding target internal resistance value is searched from the pre-established first corresponding relationship, and then the corresponding target EIS amplitude value is searched from the pre-established second corresponding relationship.

[0020] In one embodiment of the present invention, during the process of injecting the current disturbance into the DC-DC converter, determining the actual EIS amplitude of the EIS response at the set frequency includes:

[0021] During the current disturbance injection, collecting a response signal of the DC-DC converter to the current disturbance; wherein the response signal is a change in voltage or current;

[0022] Preprocessing the collected response signal, and using electrochemical impedance spectroscopy analysis technology to perform Fourier transform on the preprocessed response signal;

[0023] From the Fourier transform result, a response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

[0024] To achieve the above-mentioned purpose, the second aspect of the present invention proposes a fuel cell humidity control device, including: a first control module, used to start an on-load purge program when the power system of the fuel cell is ready to shut down; wherein the on-load purge program is used to provide a predetermined flow rate of airflow to the fuel cell stack to purge the inside of the fuel cell stack; a second control module, used to inject a sinusoidal current signal of a set frequency as a current disturbance into a DC-DC converter connected to the fuel cell stack when the on-load purge program is started, so as to induce an electrochemical impedance spectroscopy (EIS) response; a determination module, used to determine the actual EIS amplitude of the EIS response at the set frequency during the process of injecting the current disturbance into the DC-DC converter; a third control module, used to control the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude.

[0025] According to the fuel cell humidity control device of the embodiment of the present invention, when the power system of the fuel cell is ready to shut down, the on-load purge program is started by the first control module, and the on-load purge program is used to provide a predetermined flow of airflow to the fuel cell stack to purge the inside of the fuel cell stack. When the on-load purge program is started, the second control module injects a sinusoidal current signal of a set frequency as a current disturbance into the DC-DC converter connected to the fuel cell stack to induce an electrochemical impedance spectroscopy EIS response. The actual EIS amplitude of the EIS response at the set frequency is determined by the determination module during the process of injecting current disturbance into the DC-DC converter, and the internal humidity of the fuel cell after the shutdown is controlled by the third control module according to the actual EIS amplitude. Therefore, the device continuously injects a current disturbance of a set frequency into the DC-DC converter during the shutdown of the power system of the fuel cell by adding an EIS detection function, and obtains the EIS amplitude generated by the current disturbance, and controls the internal humidity of the fuel cell after the shutdown according to the EIS amplitude, which can not only save downtime, but also improve the operating reliability of the fuel cell power system.

[0026] In addition, the fuel cell humidity control device provided in the second embodiment of the present invention may also have the following additional technical features:

[0027] In one embodiment of the present invention, the third control module is used to control the internal humidity of the fuel cell after the fuel cell is shut down according to the actual EIS amplitude, including:

[0028] Predetermining a target humidity that the fuel cell stack needs to reach when shutting down;

[0029] Determining a target EIS amplitude according to the target humidity;

[0030] The actual EIS amplitude is compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the on-load purge procedure is stopped and the injection of the current disturbance into the DC-DC converter is stopped at the same time to complete the control of the internal humidity of the fuel cell after shutdown.

[0031] In one embodiment of the present invention, the third control module is used to determine the target EIS amplitude according to the target humidity, including:

[0032] Pre-establishing a first corresponding relationship between internal resistance and humidity, and a second corresponding relationship between EIS amplitude and internal resistance of the fuel cell stack under different shutdown conditions;

[0033] When the power system of the fuel cell is ready to shut down, obtaining current shutdown operating condition information;

[0034] According to the acquired current shutdown condition information and the target humidity, the corresponding target internal resistance value is searched from the pre-established first corresponding relationship, and then the corresponding target EIS amplitude value is searched from the pre-established second corresponding relationship.

[0035] In one embodiment of the present invention, the second control module is used to determine the actual EIS amplitude of the EIS response at the set frequency during the process of injecting the current disturbance into the DC-DC converter, including:

[0036] During the current disturbance injection, collecting a response signal of the DC-DC converter to the current disturbance; wherein the response signal is a change in voltage or current;

[0037] Preprocessing the collected response signal, and using electrochemical impedance spectroscopy analysis technology to perform Fourier transform on the preprocessed response signal;

[0038] From the Fourier transform result, a response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

[0039] To achieve the above object, the third aspect of the present invention further provides an electronic device, including:

[0040] at least one processor; and,

[0041] a memory communicatively connected to the at least one processor; wherein,

[0042] The memory stores instructions that can be executed by the at least one processor. The instructions are executed by the at least one processor so that the at least one processor can perform the above method.

[0043] The electronic device of the embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0044] To achieve the above objectives, the fourth aspect of the present invention further proposes a computer-readable storage medium, wherein the computer instructions are used to enable the computer to execute the above method.

[0045] The computer-readable storage medium of an embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0046] To achieve the above-mentioned purpose, a fifth aspect of the present invention further provides a computer program product, which executes the above-mentioned method when an instruction processor in the computer program product executes it.

[0047] The computer program product of the embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0048] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0050] Figure 1 is a flow chart of a fuel cell humidity control method according to an embodiment of the present invention;

[0051] Figure 2 is a schematic diagram of a fuel cell control system according to an embodiment of the present invention;

[0052] Figure 3 4 is a block diagram of a fuel cell humidity control device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0053] Embodiments of the present invention are described in detail below, 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 should not be construed as limiting the present invention.

[0054] The following describes a fuel cell humidity control method, a control device, an electronic device, and a storage medium according to embodiments of the present invention with reference to the accompanying drawings.

[0055] Figure 1 is a flow chart of a fuel cell humidity control method according to an embodiment of the present invention.

[0056] like Figure 1 As shown, the fuel cell humidity control method according to the embodiment of the present invention comprises the following steps:

[0057] S1, when the power system of the fuel cell is ready to shut down, the on-load purge program is started; wherein the on-load purge program is used to provide a predetermined flow of airflow to the fuel cell stack to purge the inside of the fuel cell stack.

[0058] During the shutdown of the fuel cell power system, the purge gas supply system is started, and dry, pure nitrogen or air is used as the purge medium. Through the flow control valve, a predetermined flow of air is stably delivered to the air inlet of the fuel cell stack. At the same time, the air flow speed is monitored and adjusted to ensure that it remains constant during the entire purge process to avoid unnecessary impact or damage to the fuel cell stack.

[0059] S2, when the on-load purge program is started, a sinusoidal current signal of a set frequency is injected into the DC-DC converter connected to the fuel cell stack as a current disturbance to induce an electrochemical impedance spectroscopy (EIS) response.

[0060] like Figure 2As shown, in the hardware design of the DC-DC converter (i.e., DCDC device) of the power system of the fuel cell, an AC injection module is integrated, and the AC injection module is used to generate a sinusoidal current signal with a set frequency (such as 1000Hz or 1500Hz, which can be set according to actual needs). The amplitude of the sinusoidal AC signal can be flexibly adjusted according to specific needs to meet different test or operating conditions. The sinusoidal current injected by the AC module will generate certain disturbance signals, which are then captured by the DC-DC converter's own sensors and preliminary data collection is performed.

[0061] The collected disturbance data is then transmitted to the fuel cell controller FCU in real time and accurately through the highly reliable CAN (Controller Area Network) communication protocol. In the fuel cell controller FCU, these data will be used for centralized data collection, processing and advanced control algorithm calculation.

[0062] It should be noted that, in other embodiments of the present invention, the AC injection module may also be external, that is, not arranged in the DC-DC converter, and may be specifically arranged according to actual needs.

[0063] S3, during the process of injecting current disturbance into the DC-DC converter, determining the actual EIS amplitude of the EIS response at the set frequency.

[0064] Specifically, during the current disturbance injection, the response signal of the DC-DC converter to the current disturbance is collected, and the response signal is a change in voltage or current. The collected response signal is preprocessed, and the preprocessed response signal is Fourier transformed using electrochemical impedance spectroscopy analysis technology. From the result of the Fourier transform, the response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

[0065] S4, controlling the internal humidity of the fuel cell after the fuel cell is shut down according to the actual EIS amplitude.

[0066] In this step, the target humidity that the fuel cell stack needs to reach when it is shut down can be determined in advance, and the target EIS amplitude can be determined based on the target humidity. The actual EIS amplitude is then compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the load purge program is stopped, and at the same time, the injection of current disturbances into the DC-DC converter is stopped to complete the control of the internal humidity after the fuel cell is shut down.

[0067] Among them, the process of determining the target EIS amplitude according to the target humidity includes: pre-establishing a first corresponding relationship between the internal resistance and humidity of the fuel cell stack under different shutdown conditions (such as flow, pressure, temperature), and a second corresponding relationship between the EIS amplitude and the internal resistance; when the power system of the fuel cell is ready to shut down, obtaining the current shutdown condition information; based on the obtained current shutdown condition information and target humidity, searching for the corresponding target internal resistance value from the pre-established first corresponding relationship, and then searching for the corresponding target EIS amplitude from the pre-established second corresponding relationship.

[0068] The present invention integrates the EIS detection function into the DC-DC converter, uses the EIS detection technology with a set frequency to monitor the internal humidity state of the fuel cell stack in real time during the shutdown process, and accurately controls the on-load purge program accordingly to maintain the fuel cell stack within the optimal humidity range, thereby being able to accurately control the shutdown fuel cell stack state, while saving the shutdown purge time and avoiding unnecessary additional purge. In addition, the method also creates a good initial humidity condition for the fuel cell stack for the secondary startup of the fuel cell power system, ensures the normal startup of the fuel cell stack, and greatly improves the reliability of the fuel cell power system.

[0069] In other embodiments of the present invention, when the actual EIS amplitude just reaches the target EIS amplitude, the purge can be appropriately extended according to the actual situation, and then the shutdown and loaded purge state is ended.

[0070] In summary, according to the fuel cell humidity control method of the embodiment of the present invention, when the power system of the fuel cell is ready to shut down, the on-load purge program is started. When the on-load purge program is started, a sinusoidal current signal of a set frequency is injected into the DC-DC converter connected to the fuel cell stack as a current disturbance to induce an electrochemical impedance spectroscopy EIS response. In the process of injecting current disturbance into the DC-DC converter, the actual EIS amplitude of the EIS response at the set frequency is determined, and the internal humidity of the fuel cell after the shutdown is controlled according to the actual EIS amplitude. Therefore, the method continuously injects a current disturbance of a set frequency into the DC-DC converter during the shutdown of the power system of the fuel cell by adding an EIS detection function, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after the shutdown is controlled according to the EIS amplitude, which can not only save downtime, but also improve the operational reliability of the fuel cell power system.

[0071] Figure 3 4 is a block diagram of a fuel cell humidity control device according to an embodiment of the present invention.

[0072] like Figure 3As shown, the fuel cell humidity control device 300 according to the embodiment of the present invention includes: a first control module 310 , a second control module 320 , a determination module 330 and a third control module 340 .

[0073] Among them, the first control module 310 is used to start the on-load purge program when the power system of the fuel cell is ready to shut down; wherein the on-load purge program is used to provide a predetermined flow of airflow to the fuel cell stack to purge the inside of the fuel cell stack. The second control module 320 is used to inject a sinusoidal current signal of a set frequency as a current disturbance into the DC-DC converter connected to the fuel cell stack when the on-load purge program is started, so as to induce an electrochemical impedance spectroscopy EIS response. The determination module 330 is used to determine the actual EIS amplitude of the EIS response at the set frequency during the process of injecting current disturbance into the DC-DC converter. The third control module 340 is used to control the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude.

[0074] In one embodiment of the present invention, the third control module 340 is used to control the internal humidity of the fuel cell after the fuel cell is shut down according to the actual EIS amplitude, including:

[0075] Predetermine the target humidity that the fuel cell stack needs to reach when shutting down;

[0076] According to the target humidity, the target EIS amplitude is determined;

[0077] The actual EIS amplitude is compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the on-load purge procedure is stopped and the injection of current disturbance into the DC-DC converter is stopped at the same time to complete the control of the internal humidity after the fuel cell is shut down.

[0078] In one embodiment of the present invention, the third control module 340 is used to determine the target EIS amplitude according to the target humidity, including:

[0079] Pre-establishing a first corresponding relationship between internal resistance and humidity and a second corresponding relationship between EIS amplitude and internal resistance of a fuel cell stack under different shutdown conditions;

[0080] When the power system of the fuel cell is ready to shut down, obtain current shutdown condition information;

[0081] According to the acquired current shutdown condition information and target humidity, the corresponding target internal resistance value is searched from the pre-established first corresponding relationship, and then the corresponding target EIS amplitude value is searched from the pre-established second corresponding relationship.

[0082] In one embodiment of the present invention, the second control module 320 is used to determine the actual EIS amplitude of the EIS response at a set frequency during the process of injecting current disturbance into the DC-DC converter, including:

[0083] During the current disturbance injection period, a response signal of the DC-DC converter to the current disturbance is collected; wherein the response signal is a change in voltage or current;

[0084] Preprocessing the collected response signal, and using electrochemical impedance spectroscopy analysis technology to perform Fourier transform on the preprocessed response signal;

[0085] From the Fourier transform result, the response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

[0086] It should be noted that for details not disclosed in the fuel cell humidity control device of the embodiment of the present invention, please refer to the details disclosed in the fuel cell humidity control method of the embodiment of the present invention, and the details will not be repeated here.

[0087] According to the fuel cell humidity control device of the embodiment of the present invention, when the power system of the fuel cell is ready to shut down, the on-load purge program is started by the first control module, and the on-load purge program is used to provide a predetermined flow of airflow to the fuel cell stack to purge the inside of the fuel cell stack. When the on-load purge program is started, the second control module injects a sinusoidal current signal of a set frequency as a current disturbance into the DC-DC converter connected to the fuel cell stack to induce an electrochemical impedance spectroscopy EIS response. The actual EIS amplitude of the EIS response at the set frequency is determined by the determination module during the process of injecting current disturbance into the DC-DC converter, and the internal humidity of the fuel cell after the shutdown is controlled by the third control module according to the actual EIS amplitude. Therefore, the device continuously injects a current disturbance of a set frequency into the DC-DC converter during the shutdown of the power system of the fuel cell by adding an EIS detection function, and obtains the EIS amplitude generated by the current disturbance, and controls the internal humidity of the fuel cell after the shutdown according to the EIS amplitude, which can not only save downtime, but also improve the operating reliability of the fuel cell power system.

[0088] Based on the above embodiments, the present invention further provides an electronic device.

[0089] An electronic device according to an embodiment of the present invention comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the above method.

[0090] The electronic device of the embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0091] Based on the above embodiments, the present invention also proposes a computer-readable storage medium.

[0092] The computer instructions in the computer-readable storage medium of the embodiment of the present invention are used to enable a computer to execute the above method.

[0093] The computer-readable storage medium of an embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0094] Based on the above embodiments, the present invention also proposes a computer program product.

[0095] In an embodiment of the present invention, when an instruction processor in a computer program product executes, the above method is performed.

[0096] The computer program product of the embodiment of the present invention executes the above method. The method adds an EIS detection function to continuously inject a current disturbance of a set frequency into the DC-DC converter during the shutdown of the fuel cell power system, and obtains the EIS amplitude generated by the current disturbance. The internal humidity of the fuel cell after shutdown is controlled according to the EIS amplitude. This not only saves downtime, but also improves the operating reliability of the fuel cell power system.

[0097] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0098] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0099] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0100] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, 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 in other suitable ways if necessary, and then stored in a computer memory.

[0101] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0102] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0103] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0104] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A fuel cell humidity control method, characterized in that: include: When the power system of the fuel cell is ready to shut down, starting the on-load purge program; wherein the on-load purge program is used to provide a predetermined flow of airflow to the fuel cell stack to purge the inside of the fuel cell stack; When the on-load purge procedure is started, a sinusoidal current signal of a set frequency is injected into a DC-DC converter connected to the fuel cell stack as a current disturbance to induce an electrochemical impedance spectroscopy (EIS) response; During the process of injecting the current disturbance into the DC-DC converter, determining an actual EIS amplitude of the EIS response at the set frequency; The internal humidity of the fuel cell after shutdown is controlled according to the actual EIS amplitude.

2. The method according to claim 1, characterized in that The controlling the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude includes: Predetermining a target humidity that the fuel cell stack needs to reach when shutting down; Determining a target EIS amplitude according to the target humidity; The actual EIS amplitude is compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the on-load purge procedure is stopped and the injection of the current disturbance into the DC-DC converter is stopped at the same time to complete the control of the internal humidity of the fuel cell after shutdown.

3. The method according to claim 2, characterized in that Determining a target EIS amplitude according to the target humidity includes: Pre-establishing a first corresponding relationship between internal resistance and humidity, and a second corresponding relationship between EIS amplitude and internal resistance of the fuel cell stack under different shutdown conditions; When the power system of the fuel cell is ready to shut down, obtaining current shutdown operating condition information; According to the acquired current shutdown condition information and the target humidity, the corresponding target internal resistance value is searched from the pre-established first corresponding relationship, and then the corresponding target EIS amplitude value is searched from the pre-established second corresponding relationship.

4. The method according to claim 1, characterized in that: In the process of injecting the current disturbance into the DC-DC converter, determining the actual EIS amplitude of the EIS response at the set frequency includes: During the current disturbance injection, collecting a response signal of the DC-DC converter to the current disturbance; wherein the response signal is a change in voltage or current; Preprocessing the collected response signal, and using electrochemical impedance spectroscopy analysis technology to perform Fourier transform on the preprocessed response signal; From the Fourier transform result, a response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

5. A fuel cell humidity control device, characterized in that: include: A first control module is used to start a load purge program when the power system of the fuel cell is ready to shut down; wherein the load purge program is used to provide a predetermined flow of air to the fuel cell stack to purge the inside of the fuel cell stack; A second control module is used to inject a sinusoidal current signal of a set frequency as a current disturbance into a DC-DC converter connected to the fuel cell stack when the on-load purge program is started, so as to induce an electrochemical impedance spectroscopy (EIS) response; A determination module, configured to determine an actual EIS amplitude of the EIS response at the set frequency during the process of injecting the current disturbance into the DC-DC converter; The third control module is used to control the internal humidity of the fuel cell after shutdown according to the actual EIS amplitude.

6. The device according to claim 5, characterized in that The third control module is used to control the internal humidity of the fuel cell after the fuel cell is shut down according to the actual EIS amplitude, including: Predetermining a target humidity that the fuel cell stack needs to reach when shutting down; Determining a target EIS amplitude according to the target humidity; The actual EIS amplitude is compared with the target EIS amplitude. If the actual EIS amplitude exceeds the target EIS amplitude, the on-load purge procedure is stopped and the injection of the current disturbance into the DC-DC converter is stopped at the same time to complete the control of the internal humidity of the fuel cell after shutdown.

7. The device according to claim 6, characterized in that The third control module is used to determine the target EIS amplitude according to the target humidity, including: Pre-establishing a first corresponding relationship between internal resistance and humidity, and a second corresponding relationship between EIS amplitude and internal resistance of the fuel cell stack under different shutdown conditions; When the power system of the fuel cell is ready to shut down, obtaining current shutdown operating condition information; According to the acquired current shutdown condition information and the target humidity, the corresponding target internal resistance value is searched from the pre-established first corresponding relationship, and then the corresponding target EIS amplitude value is searched from the pre-established second corresponding relationship.

8. The device according to claim 5, characterized in that The second control module is used to determine the actual EIS amplitude of the EIS response at the set frequency during the process of injecting the current disturbance into the DC-DC converter, including: During the current disturbance injection, collecting a response signal of the DC-DC converter to the current disturbance; wherein the response signal is a change in voltage or current; Preprocessing the collected response signal, and using electrochemical impedance spectroscopy analysis technology to perform Fourier transform on the preprocessed response signal; From the Fourier transform result, a response component with the same frequency as the injected sinusoidal current signal is extracted, and the amplitude of the response component is calculated as the actual EIS amplitude.

9. An electronic device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 4.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the program instructions are executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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