A method for identifying the attenuation of fuel cell vehicle stack operation stability

Abstract

The present invention relates to the field of fuel cell technology, and in particular to a method for identifying the attenuation of the operational stability of a fuel cell vehicle stack. The method comprises the following steps: obtaining a first data set of the fuel cell stack of the fuel cell vehicle, processing the data set to obtain an effective operational data set; determining first and second operational characteristic time intervals and corresponding first and second effective operational data sets, performing fitting calculations to obtain respective voltage fitting values, and further analyzing the method to obtain a fuel cell stack fitting determination coefficient; calculating the relative deviation values ​​of the fuel cell stack fitting determination coefficients of the first and second operational characteristic time intervals, and determining whether the operational stability of the fuel cell stack has attenuated based on the relative deviation values. The present invention does not require the fuel cell stack to be disassembled from the vehicle for bench testing by traditional means, thereby significantly saving test resource requirements. At the same time, the method can also obtain the operational stability changes of the fuel cell stack in all time periods, providing technical support for the overhaul and maintenance of the stack product.

Description

Technical Field

[0001] The present invention relates to the field of fuel cell technology, and in particular to a method for identifying attenuation of operating stability of a fuel cell vehicle stack. Background Art

[0002] During actual road driving, fuel cell vehicles are continuously affected by factors such as vehicle acceleration and deceleration, road vibration excitation, changes in ambient temperature and humidity, and air pollutants. The output performance of the fuel cell engine will attenuate to a certain extent as the vehicle mileage and engine operating time increase. This is manifested as a decrease in the output power of the fuel cell stack under rated operating conditions and a decrease in the operating stability of the fuel cell stack.

[0003] However, currently available documents do not address the monitoring, determination, and identification of fuel cell stack operational stability during actual road driving. Furthermore, the testing resources and costs required to disassemble and test a vehicle's fuel cell stack are too high to meet the needs of the "3+2" urban agglomeration, which will exceed 10,000 vehicles. Therefore, there is an urgent need for an efficient, fast, and easy-to-use method for identifying and analyzing the operational stability of fuel cell stacks, thereby providing technical support for companies to overhaul and maintain fuel cell stack products. Summary of the Invention

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] According to a first aspect of the present invention, the present invention claims protection for a method for identifying attenuation of fuel cell vehicle stack operation stability, comprising:

[0006] Acquiring a first data set of a fuel cell stack of the fuel cell vehicle, and cleaning and screening the first data set to obtain an effective operation data set of the fuel cell stack;

[0007] Setting an operating state identification time interval of the fuel cell stack, and determining a first operating characteristic time interval and a second operating characteristic time interval of the fuel cell stack in combination with a first operating characteristic moment and a second operating characteristic moment of the fuel cell stack;

[0008] Based on the valid operation data set, obtaining a first valid operation data set and a second valid operation data set corresponding to the first operation characteristic time interval and the second operation characteristic time interval;

[0009] performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operating data set and the second effective operating data set to obtain voltage fitting values ​​corresponding to the first operating characteristic time interval and the second operating characteristic time interval, respectively;

[0010] Calculating the fuel cell stack fitting determination coefficients for the first and second operating characteristic time intervals based on the first and second valid operating data sets and the voltage fitting values ​​for the first and second operating characteristic time intervals;

[0011] A relative deviation value of the fuel cell stack fitting determination coefficient between the first operation characteristic time interval and the second operation characteristic time interval is calculated, and whether the fuel cell stack operation stability is attenuated is determined based on the relative deviation value.

[0012] Furthermore, the step of obtaining a first data set of a fuel cell stack of the fuel cell vehicle further includes:

[0013] The vehicle uploaded data of the fuel cell vehicle from the start of data uploading to the current moment is obtained, including information sending time, fuel cell current and fuel cell voltage, and recorded as a first data set.

[0014] Furthermore, the cleaning and screening of the first data set to obtain an effective operating data set of the fuel cell stack includes:

[0015] Setting a minimum power threshold of the fuel cell stack, a minimum and maximum thresholds for fuel cell current validity, and a minimum and maximum thresholds for fuel cell voltage validity;

[0016] The first data set is cleaned and screened according to multiple thresholds to obtain an effective operation data set of the fuel cell stack.

[0017] Furthermore, the setting of the operating state identification time interval of the fuel cell stack, combining the first operating characteristic moment and the second operating characteristic moment of the fuel cell stack to determine the first operating characteristic time interval and the second operating characteristic time interval of the fuel cell stack, further includes:

[0018] Setting an operating status identification time interval of the fuel cell stack;

[0019] A first operating characteristic moment and a second operating characteristic moment of the fuel cell stack are extracted, and an operating characteristic time interval of the first fuel cell stack and an operating characteristic time interval of the second fuel cell stack are calculated.

[0020] Furthermore, the method of performing curve fitting between the voltage and current of the fuel cell stack using the least squares method based on the first effective operating data set and the second effective operating data set to obtain voltage fitting values ​​corresponding to the first operating characteristic time interval and the second operating characteristic time interval, respectively, further includes:

[0021] performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operation data set to obtain a voltage fitting value corresponding to the first operation characteristic time interval;

[0022] Based on the second effective operation data set, a least squares method is used to perform curve fitting between the voltage and current of the fuel cell stack to obtain a voltage fitting value corresponding to the second operation characteristic time interval.

[0023] Furthermore, the calculation of the fuel cell stack fitting determination coefficients for the first and second operating characteristic time intervals based on the first and second valid operating data sets and the voltage fitting values ​​for the first and second operating characteristic time intervals further includes:

[0024] Calculating a fuel cell stack fitting determination coefficient for the first operating characteristic time interval based on the first valid operating data set and the voltage fitting value for the first operating characteristic time interval;

[0025] The fuel cell stack fitting determination coefficient of the second operating characteristic time interval is calculated based on the second effective operating data set and the voltage fitting value of the second operating characteristic time interval.

[0026] Furthermore, the calculation of the fuel cell stack fitting determination coefficient of the first operating characteristic time interval based on the first valid operating data set and the voltage fitting value of the first operating characteristic time interval further includes:

[0027] Based on the first valid operating data set and the voltage fitting value of the fuel cell stack in the first operating characteristic time interval, calculating the average value, the residual sum of squares and the total sum of squares of the fuel cell stack fitting voltage in the first operating characteristic time interval;

[0028] The fuel cell stack fitting determination coefficient of the first operating characteristic time interval is calculated based on the fuel cell stack fitting residual sum of squares and the total sum of squares of the first operating characteristic time interval.

[0029] Furthermore, the calculation of the fuel cell stack fitting determination coefficient of the second operating characteristic time interval based on the second effective operating data set and the voltage fitting value of the second operating characteristic time interval further includes:

[0030] Based on the second valid operating data set and the voltage fitting value of the fuel cell stack in the second operating characteristic time interval, calculating the average value, the residual sum of squares and the total sum of squares of the fuel cell stack fitting voltage in the second operating characteristic time interval;

[0031] The fuel cell stack fitting determination coefficient for the second operating characteristic time interval is calculated based on the fuel cell stack fitting residual sum of squares and the total sum of squares for the second operating characteristic time interval.

[0032] Furthermore, the calculating of the relative deviation value of the fuel cell stack fitting determination coefficient between the first operation characteristic time interval and the second operation characteristic time interval, and determining whether the fuel cell stack operation stability has decayed based on the relative deviation value, further includes:

[0033] Comparing the relative deviation value with a set reference threshold value to determine whether the operating stability of the fuel cell stack has declined;

[0034] If the relative deviation value is greater than a set reference threshold, it indicates that the fuel cell stack operation stability has decayed;

[0035] Otherwise, it means that the operating stability of the fuel cell stack has not declined.

[0036] The present invention relates to the field of fuel cell technology, and in particular to a method for attenuating the operational stability of a fuel cell vehicle stack based on a big data platform. The method comprises the following steps: obtaining a first data set of a fuel cell stack of a fuel cell vehicle, processing the data set to obtain an effective operational data set; determining first and second operational characteristic time intervals and corresponding first and second effective operational data sets, performing fitting calculations to obtain respective voltage fitting values, and further analyzing the method to obtain a fuel cell stack fitting coefficient; calculating the relative deviation values ​​of the fuel cell stack fitting coefficients of the first and second operational characteristic time intervals, and determining whether the operational stability of the fuel cell stack has attenuated based on the relative deviation values. The present invention does not require the fuel cell stack to be disassembled from the vehicle for bench testing by traditional means, thereby greatly saving the demand for experimental resources. At the same time, the method can also obtain the operational stability changes of the fuel cell stack in all time periods, providing technical support for the overhaul and maintenance of the stack product. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A flowchart of a method for identifying attenuation of fuel cell vehicle stack operation stability as claimed in an embodiment of the present invention;

[0038] Figure 2 A schematic diagram of test results of a method for identifying attenuation of fuel cell vehicle stack operation stability, as claimed in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0040] The terms "first," "second," and "third" in this disclosure are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, features specified as "first," "second," or "third" may explicitly or implicitly include at least one of such features. In the description of this disclosure, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this disclosure are intended only to illustrate the relative positional relationships and movement of components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements and may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to such process, method, product, or apparatus.

[0041] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0042] According to the first embodiment of the present invention, referring to Figure 1 The present invention claims a method for identifying the attenuation of the operational stability of a fuel cell vehicle stack, comprising:

[0043] S1, obtaining a first data set of a fuel cell stack of the fuel cell vehicle, and cleaning and screening the first data set to obtain an effective operation data set of the fuel cell stack;

[0044] S2, setting an operating state identification time interval of the fuel cell stack, and determining a first operating characteristic time interval and a second operating characteristic time interval of the fuel cell stack in combination with a first operating characteristic moment and a second operating characteristic moment of the fuel cell stack;

[0045] S3, based on the valid operation data set, obtaining a first valid operation data set and a second valid operation data set corresponding to the first operation characteristic time interval and the second operation characteristic time interval;

[0046] S4, performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operation data set and the second effective operation data set to obtain voltage fitting values ​​corresponding to the first operation characteristic time interval and the second operation characteristic time interval, respectively;

[0047] S5, calculating a fuel cell stack fitting determination coefficient for the first and second operating characteristic time intervals based on the first and second valid operating data sets and the voltage fitting values ​​for the first and second operating characteristic time intervals;

[0048] S6, calculating a relative deviation value of the fuel cell stack fitting determination coefficient between the first operation characteristic time interval and the second operation characteristic time interval, and determining whether the fuel cell stack operation stability has decayed based on the relative deviation value.

[0049] Furthermore, the S1 further includes:

[0050] The vehicle uploaded data of the fuel cell vehicle from the start of data uploading to the current moment is obtained, including information sending time, fuel cell current and fuel cell voltage, and recorded as a first data set.

[0051] Among them, in this embodiment, based on the fuel cell vehicle big data platform, the vehicle uploaded data of the fuel cell vehicle from the start of uploading data to the current moment is extracted, covering the information sending time t, fuel cell current and fuel cell voltage , recorded as the first data set S.

[0052] Furthermore, the S1 further includes:

[0053] Setting a minimum power threshold of the fuel cell stack, a minimum and maximum thresholds for fuel cell current validity, and a minimum and maximum thresholds for fuel cell voltage validity;

[0054] The first data set is cleaned and screened according to multiple thresholds to obtain an effective operation data set of the fuel cell stack.

[0055] In this embodiment, the minimum power threshold of the fuel cell stack is set , minimum threshold value of fuel cell current effectiveness With the maximum threshold , minimum threshold value of fuel cell voltage validity and maximum threshold , perform data cleaning and screening on the first data set S to obtain the effective operation data set of the fuel cell stack ( );

[0056]

[0057] in represents the fuel cell current, represents the fuel cell voltage, Indicates the minimum power threshold of the fuel cell stack, and Indicates the minimum and maximum thresholds for fuel cell current effectiveness, and Indicates the minimum and maximum thresholds for fuel cell voltage validity, Indicates belonging to a symbol;

[0058] Combined with the time interval for vehicle data upload (s), calculate the cumulative operating time of the fuel cell stack (h);

[0059]

[0060] in Represents a valid operating data set for a fuel cell stack The total number of rows.

[0061] Furthermore, the S2 further includes:

[0062] Setting an operating status identification time interval of the fuel cell stack;

[0063] A first operating characteristic moment and a second operating characteristic moment of the fuel cell stack are extracted, and an operating characteristic time interval of the first fuel cell stack and an operating characteristic time interval of the second fuel cell stack are calculated.

[0064] In this embodiment, the fuel cell stack operation status identification time interval is set to , extract the first fuel cell stack operating characteristic moment And the second fuel cell stack operating characteristic time , the first running characteristic time interval is calculated as [ , ], the second operating characteristic time interval is [ , ];

[0065] Specific requirements:

[0066] ;

[0067] Furthermore, in this embodiment, the step S3 further includes:

[0068] Effective operation data set based on fuel cell stack Extract the first valid operation data set corresponding to the first operation feature time interval and the second valid operation data set corresponding to the second operation characteristic time interval ;

[0069] ;

[0070] .

[0071] Furthermore, the S4 further includes:

[0072] performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operation data set to obtain a voltage fitting value corresponding to the first operation characteristic time interval;

[0073] Based on the second effective operation data set, a least squares method is used to perform curve fitting between the voltage and current of the fuel cell stack to obtain a voltage fitting value corresponding to the second operation characteristic time interval.

[0074] In this embodiment, the effective operating data set for the first fuel cell stack is , the curve fitting between the fuel cell stack voltage and the fuel cell current is performed by the least squares method to obtain the fuel cell stack performance fitting formula for the first operating characteristic time interval

[0075] ;

[0076] in represents the fuel cell stack voltage fitting value in the first operating characteristic time interval, Indicates the number of cells in the fuel cell stack, represents the fuel cell stack performance fitting constant of the first operating characteristic time interval, represents the natural logarithm operation, represents the fuel cell current, Indicates belonging to a symbol;

[0077] Valid operating data set for the second fuel cell stack , performing curve fitting between the fuel cell stack voltage and the fuel cell current by the least squares method to obtain a fuel cell stack performance fitting formula for the second operating characteristic time interval;

[0078] ;

[0079] in represents the fuel cell stack voltage fitting value in the second operating characteristic time interval, Indicates the number of cells in the fuel cell stack, represents the fuel cell stack performance fitting constant of the second operating characteristic time interval, represents the natural logarithm operation, represents the fuel cell current, Indicates belonging to the symbol.

[0080] Furthermore, the S5 further includes:

[0081] Calculating a fuel cell stack fitting determination coefficient for the first operating characteristic time interval based on the first valid operating data set and the voltage fitting value for the first operating characteristic time interval;

[0082] The fuel cell stack fitting determination coefficient of the second operating characteristic time interval is calculated based on the second effective operating data set and the voltage fitting value of the second operating characteristic time interval.

[0083] Furthermore, the calculation of the fuel cell stack fitting determination coefficient of the first operating characteristic time interval based on the first valid operating data set and the voltage fitting value of the first operating characteristic time interval further includes:

[0084] Based on the first valid operating data set and the voltage fitting value of the fuel cell stack in the first operating characteristic time interval, calculating the average value, the residual sum of squares and the total sum of squares of the fuel cell stack fitting voltage in the first operating characteristic time interval;

[0085] The fuel cell stack fitting determination coefficient of the first operating characteristic time interval is calculated based on the fuel cell stack fitting residual sum of squares and the total sum of squares of the first operating characteristic time interval.

[0086] Furthermore, the calculation of the fuel cell stack fitting determination coefficient of the second operating characteristic time interval based on the second effective operating data set and the voltage fitting value of the second operating characteristic time interval further includes:

[0087] Based on the second valid operating data set and the voltage fitting value of the fuel cell stack in the second operating characteristic time interval, calculating the average value, the residual sum of squares and the total sum of squares of the fuel cell stack fitting voltage in the second operating characteristic time interval;

[0088] The fuel cell stack fitting determination coefficient for the second operating characteristic time interval is calculated based on the fuel cell stack fitting residual sum of squares and the total sum of squares for the second operating characteristic time interval.

[0089] In this embodiment, based on the first valid running data set The fuel cell stack performance fitting formula for the first operating characteristic time interval , calculate the average value of the fuel cell stack fitting voltage in the first operating characteristic time interval , residual square Sum and total sum of squares ;

[0090]

[0091]

[0092]

[0093] in Indicates the first valid running data set number of rows;

[0094] Based on the second valid run data set The fuel cell stack performance fitting formula for the second operating characteristic time interval , calculate the average value of the fuel cell stack fitting voltage in the second operating characteristic time interval , residual square Sum and total sum of squares ;

[0095]

[0096]

[0097]

[0098] in Indicates the second valid running data set number of rows;

[0099] Fuel cell stack fitting residual square based on the first operating characteristic time interval Sum and total sum of squares And the fuel cell stack fitting residual square of the second operating characteristic time interval Sum and total sum of squares , calculate the fuel cell stack fitting determination coefficient of the first operating characteristic time interval And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval ;

[0100] ;

[0101] .

[0102] Furthermore, the calculating of the relative deviation value of the fuel cell stack fitting determination coefficient between the first operation characteristic time interval and the second operation characteristic time interval, and determining whether the fuel cell stack operation stability has decayed based on the relative deviation value, further includes:

[0103] Comparing the relative deviation value with a set reference threshold value to determine whether the operating stability of the fuel cell stack has declined;

[0104] If the relative deviation value is greater than a set reference threshold, it indicates that the fuel cell stack operation stability has decayed;

[0105] Otherwise, it means that the operating stability of the fuel cell stack has not declined.

[0106] In this embodiment, the fuel cell stack fitting determination coefficient of the first operating characteristic time interval is calculated as follows: And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval The relative deviation between ;

[0107]

[0108] in Indicates taking the absolute value;

[0109] Compare relative deviation values With the set reference threshold , determine whether the fuel cell stack operation stability has declined; if , it means that the fuel cell stack operation stability has declined; if , it means that the operating stability of the fuel cell stack has not declined.

[0110] The following describes the specific implementation test cases:

[0111] The selected fuel cell vehicle type is a heavy-duty truck. It has been sending data to the big data platform since June 2022, with a cumulative mileage of 112,788.3 km. The demonstration city cluster where the vehicle is located is the Beijing-Tianjin-Hebei urban agglomeration. The fuel cell stack has a rated power of 70kW, a single fuel cell stack with 242 cells, and an information transmission frequency of 0.1Hz.

[0112] Based on the fuel cell vehicle big data platform, the vehicle uploaded data of the fuel cell vehicle from the start of uploading data to the current moment is extracted, covering the information sending time t, fuel cell current and fuel cell voltage , recorded as the first data set S;

[0113] The data set S is a matrix with 1931778 rows and 3 columns. The first column is the information sending time, the second column is the fuel cell current, and the third column is the fuel cell voltage.

[0114] ;

[0115] Set the minimum power threshold of the fuel cell stack , minimum threshold value of fuel cell current effectiveness With the maximum threshold , minimum threshold value of fuel cell voltage validity and maximum threshold , perform data cleaning and screening on the first data set S to obtain the effective operation data set of the fuel cell stack ( );

[0116] ;

[0117] in represents the fuel cell current, represents the fuel cell voltage, Indicates the minimum power threshold of the fuel cell stack, and Indicates the minimum and maximum thresholds for fuel cell current effectiveness, and Indicates the minimum and maximum thresholds for fuel cell voltage validity;

[0118] Set the minimum power threshold of the fuel cell stack The minimum threshold value of fuel cell current effectiveness is 100W. is 2A, the maximum threshold The minimum threshold value of fuel cell voltage validity is 1000A. is 5V, the maximum threshold The voltage is 1000V. The first data set S is cleaned and filtered to obtain the effective operation data set of the fuel cell stack. ( );

[0119] ;

[0120] Efficiently run datasets It is a matrix of 645084 rows and 3 columns, the first column is the information sending time, the second column is the fuel cell current, and the third column is the fuel cell voltage;

[0121] Combined with the time interval for vehicle data upload (s), calculate the cumulative operating time of the fuel cell stack (h);

[0122] ;

[0123] in Represents a valid operating data set for a fuel cell stack The total number of rows;

[0124] The frequency of vehicle information transmission is 0.1Hz, and the time interval for vehicle data upload is calculated 10s;

[0125] Efficiently run datasets The matrix is ​​645084 rows and 3 columns, and the cumulative operating time of the fuel cell stack is calculated is 1791.9h;

[0126]

[0127] Set the fuel cell stack operating state identification time interval to t_interval, and extract the first fuel cell stack operating characteristic moment And the second fuel cell stack operating characteristic time , the operating characteristic time interval of the first fuel cell stack is calculated to be [ , ], the second fuel cell stack operating characteristic time interval is [ , ];

[0128]

[0129] Set the time interval t_interval to 20h and set the first fuel cell stack operating characteristic time The second fuel cell stack operation characteristic time is set to 50h. The first operating characteristic time interval is calculated to be [50,70], and the second operating characteristic time interval is calculated to be [1500,1520];

[0130] Effective operation data set based on fuel cell stack Extract the operating characteristic time interval corresponding to the first fuel cell stack as well as ;

[0131]

[0132]

[0133] It is a matrix with 7200 rows and 3 columns;

[0134]

[0135] It is a matrix with 7200 rows and 3 columns;

[0136]

[0137] against , performing curve fitting between the fuel cell stack voltage and the fuel cell current by the least squares method to obtain a fuel cell stack performance fitting formula for the first operating characteristic time interval;

[0138]

[0139] in represents the fuel cell stack voltage fitting value in the first operating characteristic time interval, Indicates the number of cells in the fuel cell stack, represents the fuel cell stack performance fitting constant of the first operating characteristic time interval, represents the natural logarithm operation, represents the fuel cell current;

[0140] After calculation, a fuel cell stack performance fitting formula for the first operating characteristic time interval is obtained;

[0141]

[0142] against , performing curve fitting between the fuel cell stack voltage and the fuel cell current by the least squares method to obtain a fuel cell stack performance fitting formula for the second operating characteristic time interval;

[0143]

[0144] in represents the fuel cell stack voltage fitting value in the second operating characteristic time interval, Indicates the number of cells in the fuel cell stack, represents the fuel cell stack performance fitting constant of the second operating characteristic time interval, represents the natural logarithm operation, represents the fuel cell current;

[0145] After calculation, a fuel cell stack performance fitting formula for the second operating characteristic time interval is obtained;

[0146]

[0147] Based on the effective operating data set of the first fuel cell stack The fuel cell stack performance fitting formula for the first operating characteristic time interval , calculate the average value of the fuel cell stack fitting voltage in the first operating characteristic time interval , residual square Sum and total sum of squares ;

[0148]

[0149]

[0150]

[0151] in express number of rows;

[0152] After calculation, the average value of the fuel cell stack fitting voltage in the first operating characteristic time interval is , residual square Sum and total sum of squares ;

[0153]

[0154]

[0155]

[0156] based on The fuel cell stack performance fitting formula for the second operating characteristic time interval , calculate the average value of the fuel cell stack fitting voltage in the second operating characteristic time interval , residual square Sum and total sum of squares ;

[0157]

[0158]

[0159]

[0160] in express number of rows;

[0161] After calculation, the average value of the fuel cell stack fitting voltage in the second operating characteristic time interval is , residual square Sum and total sum of squares ;

[0162]

[0163]

[0164]

[0165] Fuel cell stack fitting residual square based on the first operating characteristic time interval Sum and total sum of squares And the fuel cell stack fitting residual square of the second operating characteristic time interval Sum and total sum of squares , calculate the fuel cell stack fitting determination coefficient of the first operating characteristic time interval And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval ;

[0166] ;

[0167] ;

[0168] After calculation, the fuel cell stack fitting determination coefficient of the first operating characteristic time interval is And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval ;

[0169] ;

[0170] ;

[0171] Calculate the fuel cell stack fitting determination coefficient of the first operating characteristic time interval And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval The relative deviation between ;

[0172] ;

[0173] in Indicates taking the absolute value;

[0174] Reference Figure 2 , after calculation, the fuel cell stack fitting determination coefficient of the first operating characteristic time interval is And the fuel cell stack fitting determination coefficient of the second operating characteristic time interval The relative deviation between ;

[0175] ;

[0176] Compare relative deviation values With the set reference threshold , determine whether the fuel cell stack operation stability has declined; if , it means that the fuel cell stack operation stability has declined; if , it means that the fuel cell stack operation stability has not declined;

[0177] Setting the reference threshold is 0.2, due to the relative deviation value Greater than the reference threshold , so it is judged that the operating stability of the fuel cell stack has declined.

[0178] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0179] In addition, the functional units in the various embodiments of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware or in the form of software functional units. The above is only an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

[0180] The above detailed description of the specific embodiments of the invention is intended to be illustrative only, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions to the invention are also within the scope of the present invention. Therefore, equivalent changes, modifications, and improvements made without departing from the spirit and scope of the present invention are also encompassed within the scope of the present invention.

Claims

1. A method for identifying attenuation of fuel cell vehicle stack operation stability, characterized in that: include: Acquiring a first data set of a fuel cell stack of the fuel cell vehicle, and cleaning and screening the first data set to obtain an effective operation data set of the fuel cell stack; Setting an operating state identification time interval of the fuel cell stack, and determining a first operating characteristic time interval and a second operating characteristic time interval of the fuel cell stack in combination with a first operating characteristic moment and a second operating characteristic moment of the fuel cell stack; Based on the valid operation data set, obtaining a first valid operation data set and a second valid operation data set corresponding to the first operation characteristic time interval and the second operation characteristic time interval; performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operating data set and the second effective operating data set to obtain voltage fitting values ​​corresponding to the first operating characteristic time interval and the second operating characteristic time interval, respectively; Based on the first effective operation data set and the voltage fitting value of the fuel cell stack in the first operation characteristic time interval, the average value and the residual sum of squares of the fuel cell stack fitting voltage in the first operation characteristic time interval are calculated. and total sum of squares ; The residual sum of squares of the fuel cell stack fitting voltage based on the first operating characteristic time interval and total sum of squares , calculate the fuel cell stack fitting determination coefficient of the first operating characteristic time interval , ; Based on the second effective operation data set and the voltage fitting value of the fuel cell stack in the second operation characteristic time interval, the average value and the residual sum of squares of the fuel cell stack fitting voltage in the second operation characteristic time interval are calculated. and total sum of squares ; The sum of squares of the fuel cell stack fitting residuals based on the second operating characteristic time interval and total sum of squares , calculate the fuel cell stack fitting determination coefficient of the second operating characteristic time interval , ; Calculate the fuel cell stack fitting determination coefficient for the first operating characteristic time interval The fuel cell stack fitting determination coefficient of the second operating characteristic time interval The relative deviation between ; ； in Indicates taking the absolute value; Compare relative deviation values With the set reference threshold , determine whether the fuel cell stack operation stability has declined; if , it means that the fuel cell stack operation stability has declined; if , it means that the operating stability of the fuel cell stack has not declined.

2. A method for identifying attenuation of fuel cell vehicle stack operation stability according to claim 1, characterized in that: The obtaining of a first data set of a fuel cell stack of the fuel cell vehicle further includes: The vehicle uploaded data of the fuel cell vehicle from the start of data uploading to the current moment is obtained, including information sending time, fuel cell current and fuel cell voltage, and recorded as a first data set.

3. The method for identifying attenuation of fuel cell vehicle stack operation stability according to claim 1, characterized in that: The cleaning and screening of the first data set to obtain a valid operating data set of the fuel cell stack includes: Setting a minimum power threshold of the fuel cell stack, a minimum and maximum thresholds for fuel cell current validity, and a minimum and maximum thresholds for fuel cell voltage validity; The first data set is cleaned and screened according to multiple thresholds to obtain an effective operation data set of the fuel cell stack.

4. The method for identifying attenuation of fuel cell vehicle stack operation stability according to claim 1, characterized in that: The step of setting the operating state identification time interval of the fuel cell stack and determining the first operating characteristic time interval and the second operating characteristic time interval of the fuel cell stack in combination with the first operating characteristic moment and the second operating characteristic moment of the fuel cell stack further includes: Setting an operating status identification time interval of the fuel cell stack; A first operating characteristic moment and a second operating characteristic moment of the fuel cell stack are extracted, and an operating characteristic time interval of the first fuel cell stack and an operating characteristic time interval of the second fuel cell stack are calculated.

5. The method for identifying attenuation of fuel cell vehicle stack operation stability according to claim 1, characterized in that: The method further includes: performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operation data set and the second effective operation data set to obtain voltage fitting values ​​corresponding to the first operation characteristic time interval and the second operation characteristic time interval, respectively. performing curve fitting between the voltage and current of the fuel cell stack using a least squares method based on the first effective operation data set to obtain a voltage fitting value corresponding to the first operation characteristic time interval; Based on the second effective operation data set, a least squares method is used to perform curve fitting between the voltage and current of the fuel cell stack to obtain a voltage fitting value corresponding to the second operation characteristic time interval.

Images