Fuel cell nitrogen emission strategy adjustment method and system based on membrane thickness change

Abstract

A fuel cell nitrogen emission strategy adjustment method and system based on membrane thickness change belong to the field of fuel cells, and the method comprises the following steps: acquiring the real-time thickness of a proton exchange membrane at the current moment, if the real-time thickness is greater than the historical thickness, reducing the opening duration of a nitrogen discharge valve, and if the real-time thickness is less than the historical thickness, increasing the opening duration of the nitrogen discharge valve. According to the present invention, the existing nitrogen removal strategy is adjusted according to the thickness change of the proton exchange membrane, and the proton exchange membrane is thickened, such that the nitrogen permeating from the cathode to the anode is reduced, and the content of the nitrogen accumulated on the anode side is reduced so as to reduce the opening time of the nitrogen removal valve in the nitrogen removal strategy; thinning of the proton exchange membrane indicates that nitrogen permeating from the cathode to the anode is increased, the content of nitrogen accumulated on the anode side is increased, the opening duration of a nitrogen removal valve in the nitrogen removal strategy is increased, and by setting the more reasonable nitrogen removal duration changing along with the thickness of the membrane, it is guaranteed that anode nitrogen is fully discharged, meanwhile, excessive discharge of anode hydrogen is avoided, and the nitrogen removal efficiency is improved. And the reasonability of the nitrogen removal strategy is improved.

Description

Technical Field

[0001] The present application relates to the field of fuel cells, and in particular to a method and system for adjusting a fuel cell nitrogen emission strategy based on changes in membrane thickness. Background Art

[0002] Proton Exchange Membrane (PEM) is the core component of Proton Exchange Membrane Fuel Cell (PEMFC) and plays a key role in battery performance. It not only has a barrier effect, but also has the function of conducting protons. During the operation of the fuel cell, nitrogen in the air (cathode side) will penetrate into the hydrogen side (anode side) through the proton exchange membrane. The nitrogen exhaust strategy of the existing technology mainly relies on preset fixed cycles and times to control the opening and closing of the nitrogen exhaust valve. These fixed parameters are usually set based on empirical values ​​under laboratory conditions and will not be adjusted with changes in operating conditions in actual applications.

[0003] For example, a common solution is to set the nitrogen exhaust valve to open at regular intervals for a certain period of time. This method is based on an assumed nitrogen permeation rate and a fixed membrane thickness, attempting to regularly remove accumulated nitrogen without affecting the operation of the fuel cell. However, this method cannot cope with the possible changes in the thickness of the proton exchange membrane during the operation of the fuel cell.

[0004] Specifically, the thickness of the proton exchange membrane may change during operation due to chemical degradation, mechanical damage, etc. A thinner membrane thickness will increase the nitrogen permeation rate, while a thicker membrane thickness will decrease the nitrogen permeation rate. The fixed cycle and time nitrogen removal strategy does not take into account the possible changes in the thickness of the proton exchange membrane during the operation of the fuel cell. When the membrane thickness changes, the fixed strategy may not be able to effectively remove nitrogen, resulting in nitrogen accumulation or excessive hydrogen removal.

[0005] For example, if the nitrogen exhaust valve is opened too frequently or for too long, it will cause excessive hydrogen emissions, waste hydrogen resources, and reduce the overall efficiency of the system. If the nitrogen exhaust valve is opened too infrequently or for too short a time, nitrogen and other impurities will accumulate, affecting battery performance, causing low single-chip voltage, and even shortening the life of the battery stack. Summary of the invention

[0006] The present application provides a method and system for adjusting a fuel cell nitrogen emission strategy based on membrane thickness changes, which can solve the technical problem of unreasonable opening time of a nitrogen exhaust valve existing in the prior art.

[0007] In a first aspect, an embodiment of the present application provides a method for adjusting a nitrogen emission strategy of a fuel cell based on a change in membrane thickness, the method comprising:

[0008] The real-time thickness of the proton exchange membrane at the current moment is obtained, and the real-time thickness is compared with the historical thickness at the previous moment. If the real-time thickness is greater than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is reduced; if the real-time thickness is less than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is increased.

[0009] In combination with the first aspect, in one embodiment, obtaining the real-time thickness of the proton exchange membrane specifically comprises the following steps:

[0010] Collect the real-time temperature and humidity of the fuel cell, and the real-time resistance of the proton exchange membrane;

[0011] The real-time thickness of the proton exchange membrane is obtained by calculation based on the real-time temperature, real-time humidity, and real-time resistance.

[0012] In combination with the first aspect, in one embodiment, the real-time temperature is the temperature at the outlet of the fuel cell cooling channel, and the real-time humidity is the humidity at the outlet of the fuel cell air channel.

[0013] In combination with the first aspect, in one implementation, calculating the real-time thickness according to the real-time temperature, the real-time humidity, and the real-time resistance value specifically includes the following steps:

[0014] Calculating according to the real-time humidity to obtain the real-time water content of the proton exchange membrane;

[0015] Calculating according to the real-time temperature and the real-time water content to obtain the real-time conductivity of the proton exchange membrane;

[0016] The real-time thickness of the proton exchange membrane is obtained by calculation based on the real-time conductivity and the real-time resistance.

[0017] In combination with the first aspect, in one implementation, the real-time thickness is calculated using the following formula:

[0018] t m =R m ×σ(T,λ)

[0019] Among them, t m represents the real-time thickness of the proton exchange membrane, R m represents the real-time resistance of the proton exchange membrane, T represents the real-time temperature of the fuel cell, λ represents the real-time water content of the proton exchange membrane, and σ(T, λ) represents the real-time conductivity of the proton exchange membrane at the real-time temperature and real-time water content.

[0020] In combination with the first aspect, in one embodiment, the real-time conductivity is calculated using the following formula:

[0021]

[0022] Wherein, σ(T, λ) represents the real-time conductivity of the proton exchange membrane at the real-time temperature and real-time water content, λ represents the real-time water content of the proton exchange membrane, T represents the real-time temperature of the fuel cell, and σ 303k (λ)=0.005193λ-0.00326.

[0023] In combination with the first aspect, in one implementation, the real-time moisture content is calculated using the following formula:

[0024]

[0025] Where, λ represents the real-time water content of the proton exchange membrane, a w Indicates the real-time humidity of the fuel cell.

[0026] In combination with the first aspect, in one embodiment, when the real-time thickness is different from the historical thickness, the time adjustment amount is obtained by calculating the real-time nitrogen concentration of the anode of the fuel cell, and the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is adjusted according to the market adjustment amount;

[0027] The real-time nitrogen concentration is calculated using the following formula:

[0028]

[0029] Where M(t) represents the real-time nitrogen concentration of the fuel cell anode at the current time t, t represents the current time, V represents the volume of the fuel cell anode space, C ca represents the nitrogen concentration at the cathode of the fuel cell, M0 represents the nitrogen content at the anode of the fuel cell at the initial time 0, represents the nitrogen permeability coefficient, e represents the natural constant, t m Indicates the real-time thickness of the proton exchange membrane.

[0030] In combination with the first aspect, in one embodiment, the method further includes periodically detecting the real-time thickness to determine whether to adjust the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy;

[0031] The detection period is negatively correlated with the ambient temperature and ambient pressure of the operating environment of the fuel cell.

[0032] In a second aspect, an embodiment of the present application provides a fuel cell nitrogen emission strategy adjustment system based on membrane thickness change, the system comprising:

[0033] A data acquisition module, which is used to obtain the real-time thickness of the proton exchange membrane at the current moment;

[0034] The data processing module is used to compare the real-time thickness with the historical thickness at the previous moment. If the real-time thickness is greater than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is reduced; if the real-time thickness is less than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is increased.

[0035] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:

[0036] The existing nitrogen removal strategy is adjusted according to the change in the thickness of the proton exchange membrane. If the proton exchange membrane becomes thicker, it means that the amount of nitrogen penetrating from the cathode to the anode decreases, and the nitrogen content accumulated on the anode side decreases, then the opening time of the nitrogen removal valve in the nitrogen removal strategy is reduced; if the proton exchange membrane becomes thinner, it means that the amount of nitrogen penetrating from the cathode to the anode increases, and the nitrogen content accumulated on the anode side increases, then the opening time of the nitrogen removal valve in the nitrogen removal strategy is increased. By setting a more reasonable nitrogen removal time that changes with the membrane thickness, it is possible to ensure that the anode nitrogen is fully discharged while avoiding excessive discharge of anode hydrogen, thereby improving the rationality of the nitrogen removal strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of an embodiment of a method for adjusting a fuel cell nitrogen emission strategy based on a membrane thickness change according to the present application;

[0038] Figure 2 This is a schematic diagram of the location of the temperature sensor and humidity sensor;

[0039] Figure 3 For this application Figure 1 Detailed flow chart of step S1 in FIG.

[0040] Figure 4 For this application Figure 3 Detailed flow chart of step S12;

[0041] Figure 5 This is a functional module diagram of an embodiment of a fuel cell nitrogen emission strategy adjustment system based on membrane thickness change of the present application;

[0042] Figure 6 This is a schematic diagram of the hardware structure of a fuel cell nitrogen emission strategy adjustment device based on membrane thickness change involved in an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0045] In a first aspect, an embodiment of the present application provides a method for adjusting a fuel cell nitrogen emission strategy based on changes in membrane thickness.

[0046] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of an embodiment of a method for adjusting a fuel cell nitrogen emission strategy based on membrane thickness variation according to the present application. Figure 1 As shown, the method for adjusting the fuel cell nitrogen emission strategy based on the change of membrane thickness includes:

[0047] Step S1, obtaining the real-time thickness of the proton exchange membrane at the current moment.

[0048] Step S2, comparing the real-time thickness with the historical thickness at the previous moment, if the real-time thickness is greater than the historical thickness, reducing the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy, if the real-time thickness is less than the historical thickness, increasing the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy.

[0049] In the existing nitrogen removal strategy, the opening frequency and opening time of the nitrogen removal valve are calibrated in advance according to the performance of the corresponding fuel cell. When formulating the nitrogen removal strategy, it is assumed that the thickness of the proton exchange membrane remains unchanged, and the corresponding nitrogen concentration permeating from the cathode side to the anode side through the proton exchange membrane per unit time remains unchanged. However, during the operation of the fuel cell, the thickness of the proton exchange membrane inside it may change with the operating environment. For example, after the fuel cell has been operated in a high temperature and high pressure environment for a period of time, the thickness of the proton exchange membrane may become smaller. If the membrane thickness becomes smaller, the concentration of nitrogen permeating from the cathode side to the anode side through the proton exchange membrane may increase. If the opening time of the nitrogen removal valve in the existing nitrogen removal strategy is still followed, the nitrogen removal valve will continue to be opened after the nitrogen concentration is exhausted, which will cause excessive hydrogen on the anode side to be discharged, thereby affecting the performance of the fuel cell.

[0050] In this embodiment, the existing nitrogen removal strategy is adjusted according to the change in the thickness of the proton exchange membrane. The thickening of the proton exchange membrane indicates that the nitrogen permeating from the cathode to the anode is reduced, and the nitrogen content accumulated on the anode side is reduced, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is reduced. The thinning of the proton exchange membrane indicates that the nitrogen permeating from the cathode to the anode is increased, and the nitrogen content accumulated on the anode side is increased, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is increased. By setting a more reasonable nitrogen removal time that changes with the membrane thickness, it is ensured that the anode nitrogen is fully discharged while avoiding excessive discharge of anode hydrogen, thereby improving the rationality of the nitrogen removal strategy.

[0051] Further, in one embodiment, referring to Figure 3 The above-mentioned method of obtaining the real-time thickness of the proton exchange membrane specifically includes the following steps:

[0052] Step S11, collecting the real-time temperature and real-time humidity of the fuel cell, and the real-time resistance value of the proton exchange membrane.

[0053] Step S12: Calculate the real-time thickness of the proton exchange membrane according to the real-time temperature, real-time humidity, and real-time resistance.

[0054] Preferably, refer to Figure 2 The above-mentioned real-time temperature is the temperature at the outlet of the fuel cell cooling channel, and the real-time humidity is the humidity at the outlet of the fuel cell air channel.

[0055] Preferably, refer to Figure 4 , calculate the real-time thickness according to the real-time temperature, real-time humidity, and real-time resistance, specifically including the following steps:

[0056] Step S121, calculating according to the real-time humidity to obtain the real-time water content of the proton exchange membrane.

[0057] Step S122: Calculate according to the real-time temperature and the real-time water content to obtain the real-time conductivity of the proton exchange membrane.

[0058] Step S123: Calculate the real-time thickness of the proton exchange membrane according to the real-time conductivity and the real-time resistance.

[0059] In this embodiment, the resistance of the proton exchange membrane of the fuel cell is measured using an electrochemical impedance spectroscopy (EIS) device to obtain the resistance R m Install a temperature sensor at a suitable location of the fuel cell to obtain the temperature T of the fuel cell. Install a humidity sensor at a suitable location of the fuel cell to obtain the humidity a of the fuel cell. w , the subscript w has no actual meaning.

[0060] For fuel cell proton exchange membrane thickness R m The calculation of involves the following formula (1):

[0061]

[0062] Among them, t m represents the real-time thickness of the proton exchange membrane, σ represents the conductivity of the proton exchange membrane, λ represents the real-time water content of the proton exchange membrane, z represents the thickness of the proton exchange membrane, and the subscript m has no actual meaning. During the operation of the fuel cell system, it can be considered that the real-time water content λ is uniformly distributed within the entire thickness of the membrane, and the conductivity σ of the proton exchange membrane can also be considered uniform, so the above formula (1) can be transformed into the following formula (2):

[0063]

[0064] Wherein, σ(T, λ) represents the real-time conductivity σ of the proton exchange membrane at the real-time temperature T and the real-time water content λ.

[0065] For fuel cells, the conductivity σ of the proton exchange membrane is closely related to the water content λ. Calculating the water content λ is one of the key steps in determining the conductivity σ. The water content λ of the proton exchange membrane can be obtained by the following formula (3):

[0066]

[0067] Among them, a w Represents the humidity of the fuel cell. This formula is a general formula for calculating the water content.

[0068] The conductivity σ in the proton exchange membrane is closely related to the water content λ and the conductivity σ is also closely related to the temperature T. In general, the proton conductivity σ of the proton exchange membrane increases linearly with the water content λ and increases exponentially with the temperature T. The conductivity σ is calculated using the following formula (4):

[0069]

[0070] Wherein, σ(T, λ) represents the real-time conductivity σ of the proton exchange membrane at the real-time temperature T and the real-time water content λ, in units of S / cm, λ represents the real-time water content of the proton exchange membrane, T represents the real-time temperature of the fuel cell, in units of K, σ 303k (λ) = 0.005193λ - 0.00326. Each coefficient involved in formula (4) is determined according to different fuel cell systems based on experience and experimental data. Different fuel cell systems have different coefficients. 1268 represents the material temperature sensitivity of the proton exchange membrane. σ 303k(λ) This is the change of conductivity σ with the change of water content λ at the reference temperature of 303K (the reference temperature can be customized, and the coefficients involved must also be changed). 0.005193 is the coefficient of water content λ, which indicates the intensity of the influence of water content λ on conductivity σ, and -0.00326 is an offset constant.

[0071] Combining the above steps, we can get the resistance value R of the proton exchange membrane according to the measurement. m 、Fuel cell humidity a w 2 , the fuel cell temperature T is used to calculate the thickness of the proton exchange membrane t m , as shown in formula (5):

[0072]

[0073] After calculating the real-time thickness of the proton exchange membrane, determine whether the thickness of the proton exchange membrane has changed, and adjust the existing nitrogen removal strategy according to the change in the thickness of the proton exchange membrane. The thicker the proton exchange membrane, the less nitrogen permeates from the cathode to the anode, and the nitrogen content accumulated on the anode side decreases, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is reduced. The thinner the proton exchange membrane, the more nitrogen permeates from the cathode to the anode, and the more nitrogen content accumulated on the anode side increases, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is increased. By setting a more reasonable nitrogen removal time that changes with the membrane thickness, it is ensured that the anode nitrogen is fully discharged while avoiding excessive discharge of anode hydrogen, thereby improving the rationality of the nitrogen removal strategy.

[0074] Furthermore, in some embodiments, when the above-mentioned real-time thickness is different from the historical thickness, the time adjustment amount is obtained by calculating the real-time nitrogen concentration of the anode of the fuel cell, and the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is adjusted according to the market adjustment amount.

[0075] In this embodiment, the nitrogen exhaust cycle of the nitrogen exhaust valve is re-determined by the calculated proton exchange membrane thickness. For a fuel cell, the nitrogen concentration of the anode and the proton exchange membrane have a strong correlation, and the correlation is shown in the following formula (6):

[0076]

[0077] Where M represents the nitrogen mass at the anode of the fuel cell, t represents the time, and ΔC N2 represents the nitrogen concentration difference between the positive and negative electrodes, t m represents the thickness of the proton exchange membrane, K N2 It represents the nitrogen permeability coefficient.

[0078] Since the volume V of the anode does not change, the rate at which the nitrogen at the cathode penetrates into the anode is slow, and the nitrogen concentration at the cathode C caAssume it as a constant, thus, the above formula (6) can be transformed into the following formula (7):

[0079]

[0080] From the above formula (7), the following formula (8) is obtained:

[0081]

[0082] Where M(t) represents the nitrogen mass of the fuel cell anode at the current time t, t represents the current time, V represents the volume of the fuel cell anode space, C ca represents the nitrogen concentration at the cathode of the fuel cell, M0 represents the nitrogen content at the anode of the fuel cell at the initial time 0, represents the nitrogen permeability coefficient, e represents the natural constant, t m Indicates the real-time thickness of the proton exchange membrane.

[0083] Formula (8) can be used to calculate how much nitrogen mass will be added to the fuel cell during the time when the nitrogen exhaust valve is closed. For each fuel cell, there is a tolerance for anode nitrogen. We need to make the nitrogen concentration at the anode not higher than the tolerance. When the thickness of the proton exchange membrane does not change, the nitrogen concentration can be controlled below the tolerance of the fuel cell according to the normal nitrogen exhaust cycle. Due to the change in the thickness of the proton exchange membrane, the nitrogen that penetrates into the anode during the original nitrogen exhaust valve closing time t1 increases. Using the original nitrogen exhaust valve nitrogen exhaust time t2 cannot discharge the nitrogen accumulated during t1 to a concentration below the original discharge concentration. Under the condition of normal membrane thickness, it can be calculated that the cathode will penetrate into the anode with a mass of m1 during t1. Under the condition of changed membrane thickness, it can be calculated that the cathode will penetrate into the anode with a mass of m2 during t1. Calculate m1-m2 to obtain the mass of nitrogen change caused by the change in membrane thickness, and obtain the nitrogen exhaust valve opening time t3 to be adjusted according to the changed nitrogen mass. For example, if m1-m2 is greater than 0, that is, the film thickness increases, the nitrogen exhaust valve opening time needs to be reduced by 3 seconds, and if m1-m2 is less than 0, that is, the film thickness decreases, the nitrogen exhaust valve opening time needs to be increased by 3 seconds. After the above steps, an update of the nitrogen exhaust cycle is completed.

[0084] In summary, by measuring the temperature and humidity of the fuel cell and the resistance of the proton exchange membrane, the thickness of the proton exchange membrane is calculated, and a function of the amount of nitrogen over time is obtained based on the calculated thickness of the proton exchange membrane, so as to update the current nitrogen exhaust strategy. The nitrogen exhaust strategy is optimized based on the determined membrane thickness change, thereby improving the operating efficiency and service life of the fuel cell.

[0085] In a second aspect, an embodiment of the present application also provides a fuel cell nitrogen emission strategy adjustment system based on membrane thickness changes.

[0086] In one embodiment, referring to Figure 5 , Figure 5 This is a functional module diagram of an embodiment of a fuel cell nitrogen emission strategy adjustment system based on membrane thickness change in this application. Figure 5 As shown, the fuel cell nitrogen emission strategy adjustment system based on membrane thickness change includes:

[0087] The data acquisition module 1 is used to obtain the real-time thickness of the proton exchange membrane at the current moment.

[0088] Data processing module 2 is used to compare the real-time thickness with the historical thickness at the previous moment. If the real-time thickness is greater than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is reduced; if the real-time thickness is less than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is increased.

[0089] In the existing nitrogen removal strategy, the opening frequency and opening time of the nitrogen removal valve are calibrated in advance according to the performance of the corresponding fuel cell. When formulating the nitrogen removal strategy, it is assumed that the thickness of the proton exchange membrane remains unchanged, and the corresponding nitrogen concentration permeating from the cathode side to the anode side through the proton exchange membrane per unit time remains unchanged. However, during the operation of the fuel cell, the thickness of the proton exchange membrane inside it may change with the operating environment. For example, after the fuel cell has been operated in a high temperature and high pressure environment for a period of time, the thickness of the proton exchange membrane may become smaller. If the membrane thickness becomes smaller, the concentration of nitrogen permeating from the cathode side to the anode side through the proton exchange membrane may increase. If the opening time of the nitrogen removal valve in the existing nitrogen removal strategy is still followed, the nitrogen removal valve will continue to be opened after the nitrogen concentration is exhausted, which will cause excessive hydrogen on the anode side to be discharged, thereby affecting the performance of the fuel cell.

[0090] In this embodiment, the existing nitrogen removal strategy is adjusted according to the change in the thickness of the proton exchange membrane. The thickening of the proton exchange membrane indicates that the nitrogen permeating from the cathode to the anode is reduced, and the nitrogen content accumulated on the anode side is reduced, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is reduced. The thinning of the proton exchange membrane indicates that the nitrogen permeating from the cathode to the anode is increased, and the nitrogen content accumulated on the anode side is increased, so the opening time of the nitrogen removal valve in the nitrogen removal strategy is increased. By setting a more reasonable nitrogen removal time that changes with the membrane thickness, it is ensured that the anode nitrogen is fully discharged while avoiding excessive discharge of anode hydrogen, thereby improving the rationality of the nitrogen removal strategy.

[0091] Among them, the functional implementation of each module in the above-mentioned fuel cell nitrogen emission strategy adjustment system based on membrane thickness change corresponds to the steps in the above-mentioned fuel cell nitrogen emission strategy adjustment method based on membrane thickness change embodiment, and its functions and implementation processes are no longer repeated here one by one.

[0092] In a third aspect, an embodiment of the present application provides a fuel cell nitrogen emission strategy adjustment device based on membrane thickness changes. The fuel cell nitrogen emission strategy adjustment device based on membrane thickness changes can be a personal computer (PC), a laptop computer, a server, or other device with data processing capabilities.

[0093] Reference Figure 6 , Figure 6 The hardware structure diagram of the device for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation involved in the embodiment of the present application is shown in FIG. In the embodiment of the present application, the device for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation may include a processor, a memory, a communication interface, and a communication bus.

[0094] The communication bus may be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0095] The communication interface includes an input / output (I / O) interface, a physical interface, and a logical interface, etc., which are used to realize the interconnection of devices inside the fuel cell nitrogen emission strategy adjustment device based on membrane thickness changes, and an interface for realizing the interconnection of the fuel cell nitrogen emission strategy adjustment device based on membrane thickness changes with other devices (such as other computing devices or user devices). The physical interface can be an Ethernet interface, an optical fiber interface, an ATM interface, etc. The user device can be a display, a keyboard, etc.

[0096] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0097] The processor may be a general-purpose processor, and the general-purpose processor may call a fuel cell nitrogen emission strategy adjustment program based on a membrane thickness change stored in a memory, and execute a fuel cell nitrogen emission strategy adjustment method based on a membrane thickness change provided in an embodiment of the present application. For example, the general-purpose processor may be a central processing unit (CPU). Among them, the method executed when the fuel cell nitrogen emission strategy adjustment program based on membrane thickness change is called may refer to the various embodiments of the fuel cell nitrogen emission strategy adjustment method based on membrane thickness change of the present application, which will not be repeated here.

[0098] Those skilled in the art will understand that Figure 6 The hardware structure shown in the figure does not constitute a limitation on the present application, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0099] In a fourth aspect, an embodiment of the present application also provides a computer-readable storage medium.

[0100] A fuel cell nitrogen emission strategy adjustment program based on membrane thickness change is stored on a computer-readable storage medium of the present application, wherein when the above-mentioned fuel cell nitrogen emission strategy adjustment program based on membrane thickness change is executed by a processor, the steps of the fuel cell nitrogen emission strategy adjustment method based on membrane thickness change as described above are implemented.

[0101] Among them, the method implemented when the fuel cell nitrogen emission strategy adjustment program based on membrane thickness change is executed can refer to the various embodiments of the fuel cell nitrogen emission strategy adjustment method based on membrane thickness change of the present application, and will not be repeated here.

[0102] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0103] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0104] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0105] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0106] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0107] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0108] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness change, characterized in that: The method comprises: The real-time thickness of the proton exchange membrane at the current moment is obtained, and the real-time thickness is compared with the historical thickness at the previous moment. If the real-time thickness is greater than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is reduced; if the real-time thickness is less than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is increased.

2. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness change according to claim 1, characterized in that: The method of obtaining the real-time thickness of the proton exchange membrane specifically comprises the following steps: Collect the real-time temperature and humidity of the fuel cell, and the real-time resistance of the proton exchange membrane; The real-time thickness of the proton exchange membrane is obtained by calculation based on the real-time temperature, real-time humidity, and real-time resistance.

3. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness change according to claim 2, characterized in that: The real-time temperature is the temperature at the outlet of the fuel cell cooling channel, and the real-time humidity is the humidity at the outlet of the fuel cell air channel.

4. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness change according to claim 2, characterized in that: The method of calculating the real-time thickness according to the real-time temperature, the real-time humidity, and the real-time resistance value specifically includes the following steps: Calculating according to the real-time humidity to obtain the real-time water content of the proton exchange membrane; Calculating according to the real-time temperature and the real-time water content to obtain the real-time conductivity of the proton exchange membrane; The real-time thickness of the proton exchange membrane is obtained by calculation based on the real-time conductivity and the real-time resistance.

5. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness change according to claim 1, characterized in that: The real-time thickness is calculated using the following formula: t m =R m ×σ(T,λ) Among them, t m represents the real-time thickness of the proton exchange membrane, R m represents the real-time resistance of the proton exchange membrane, T represents the real-time temperature of the fuel cell, λ represents the real-time water content of the proton exchange membrane, and σ(T, λ) represents the real-time conductivity of the proton exchange membrane at the real-time temperature and real-time water content.

6. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation according to claim 5, characterized in that: The real-time conductivity is calculated using the following formula: Wherein, σ(T, λ) represents the real-time conductivity of the proton exchange membrane at the real-time temperature and real-time water content, λ represents the real-time water content of the proton exchange membrane, T represents the real-time temperature of the fuel cell, and σ 303k (λ)=0.005193λ-0.00326.

7. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation according to claim 5, characterized in that: The real-time moisture content is calculated using the following formula: Where, λ represents the real-time water content of the proton exchange membrane, a w Indicates the real-time humidity of the fuel cell.

8. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation according to claim 1, characterized in that: When the real-time thickness is different from the historical thickness, the time adjustment amount is obtained by calculating the real-time nitrogen concentration of the anode of the fuel cell, and the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is adjusted according to the market adjustment amount; The real-time nitrogen concentration is calculated using the following formula: Where M(t) represents the real-time nitrogen concentration of the fuel cell anode at the current time t, t represents the current time, V represents the volume of the fuel cell anode space, C ca represents the nitrogen concentration at the cathode of the fuel cell, M0 represents the nitrogen content at the anode of the fuel cell at the initial time 0, represents the nitrogen permeability coefficient, e represents the natural constant, t m Indicates the real-time thickness of the proton exchange membrane.

9. The method for adjusting the nitrogen emission strategy of a fuel cell based on membrane thickness variation according to claim 1, characterized in that: The method further includes periodically detecting the real-time thickness to determine whether to adjust the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy; The detection period is negatively correlated with the ambient temperature and ambient pressure of the operating environment of the fuel cell.

10. A fuel cell nitrogen emission strategy adjustment system based on membrane thickness change, characterized in that: The system comprises: A data acquisition module, which is used to obtain the real-time thickness of the proton exchange membrane at the current moment; The data processing module is used to compare the real-time thickness with the historical thickness at the previous moment. If the real-time thickness is greater than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is reduced; if the real-time thickness is less than the historical thickness, the opening time of the nitrogen exhaust valve in the nitrogen exhaust strategy is increased.

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