A method and apparatus for on-line monitoring of capacity degradation of an energy storage device battery array

Abstract

The application relates to a kind of energy storage device battery array capacity recession on-line monitoring method and device, wherein, the method comprises: collecting the basic data of battery array, and screening initial charging interval and initial discharge interval according to current data;According to initial charging interval and initial discharge interval, effective charging interval and effective discharge interval are screened out;According to effective charging interval and effective discharge interval, approximate constant-current charging interval and approximate constant-current discharge interval are screened out;According to approximate constant-current charging interval and approximate constant-current discharge interval, large SOC change charging interval and large SOC change discharge interval are screened out;According to large SOC change charging interval, available charging capacity is calculated, and according to large SOC change discharge interval, available discharge capacity is calculated;According to available charging capacity and available discharge capacity, the capacity recession degree of battery array is calculated.The application can improve the evaluation granularity of energy storage device health degree, so that the evaluation result is more comprehensive and accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent monitoring of energy storage devices, in particular to an energy storage device battery array capacity degradation online monitoring method and device. BACKGROUND

[0002] The health degree of an energy storage device is usually determined from the overall system, which represents the overall capacity degradation of the energy storage device. However, an energy storage device is usually composed of multiple battery arrays, which work together to store and release electrical energy. The capacity, internal resistance and consistency of each battery array are different, which not only makes the overall health degree evaluation result of the energy storage device inaccurate, but also cannot reflect the health degree of each battery array.

[0003] The lack of online evaluation means for the available capacity of a battery array has become a short board affecting the service life and reliability of the energy storage device. How to use the existing collected data to evaluate the health degree of each battery array is the key to improving the operation performance of the energy storage device. In order to independently evaluate the available battery capacity of a single battery array online, more refined monitoring and evaluation means need to be introduced. SUMMARY

[0004] The technical problem to be solved by the present application is to provide an energy storage device battery array capacity degradation online monitoring method and device, which can improve the evaluation granularity of the health degree of the energy storage device and make the evaluation result more comprehensive and accurate.

[0005] The technical solution adopted by the present application to solve the technical problem is to provide an energy storage device battery array capacity degradation online monitoring method, comprising the following steps:

[0006] Collecting basic data of the battery array, the basic data including current data and state of charge data, and screening an initial charging interval and an initial discharging interval according to the current data;

[0007] Screening an effective charging interval according to the charging current data at each time in the initial charging interval, and screening an effective discharging interval according to the discharging current data at each time in the initial discharging interval;

[0008] Screening an approximately constant current charging interval according to the charging current data at each time in the effective charging interval, and screening an approximately constant current discharging interval according to the discharging current data at each time in the effective discharging interval;

[0009] Screening a large SOC change charging interval according to the charging state of charge data at each time in the approximately constant current charging interval, and screening a large SOC change discharging interval according to the discharging state of charge data at each time in the approximately constant current discharging interval;

[0010] The available charging capacity is calculated according to the charging current data and the charging state of charge data of the large SOC change charging interval, and the available discharging capacity is calculated according to the discharging current data and the discharging state of charge data of the large SOC change discharging interval.

[0011] The capacity degradation degree of the battery array is calculated according to the available charging capacity and the available discharging capacity.

[0012] The initial charging interval and the initial discharging interval are screened according to the current data, specifically, the basic data with the current data less than 0 is allocated to the initial charging interval, and the basic data with the current data greater than 0 is allocated to the initial discharging interval.

[0013] The effective charging interval is screened according to the charging current data at each time in the initial charging interval, and the effective discharging interval is screened according to the discharging current data at each time in the initial discharging interval, specifically:

[0014] The charging current data at each time in the initial charging interval is compared with the charging current screening threshold respectively, and the basic data with the absolute value of the charging current data greater than or equal to the charging current screening threshold is allocated to the effective charging interval.

[0015] The discharging current data at each time in the initial discharging interval is compared with the discharging current threshold respectively, and the basic data with the discharging current data greater than or equal to the discharging current threshold is allocated to the effective discharging interval.

[0016] The approximate constant current charging interval is screened according to the charging current data at each time in the effective charging interval, and the approximate constant current discharging interval is screened according to the discharging current data at each time in the effective discharging interval, specifically:

[0017] The difference between the charging current at the first time and the charging current at the nth time in the effective charging interval is calculated, and the difference is divided by the charging current at the first time, when the absolute value of the result is less than or equal to the charging current fluctuation threshold, the basic data corresponding to the charging current is allocated to the approximate constant current charging interval; when the absolute value of the result is greater than the charging current fluctuation threshold, the charging current at the nth time is taken as the starting time point of the next effective charging interval. ch,n The next effective charging interval starts at the starting time point;

[0018] The difference between the discharging current at the first time and the discharging current at the nth time in the effective discharging interval is calculated, and the difference is divided by the discharging current at the first time, when the absolute value of the result is less than or equal to the discharging current fluctuation threshold, the basic data corresponding to the discharging current data is allocated to the approximate constant current discharging interval; when the absolute value of the result is greater than the discharging current fluctuation threshold, the charging current at the nth time is taken as the starting time point of the next effective discharging interval.

[0019] The large SOC change charging interval is screened out according to the charging state of charge data at each time in the approximate constant current charging interval, and the large SOC change discharging interval is screened out according to the discharging state of charge data at each time in the approximate constant current discharging interval, and specifically:

[0020] The difference between the charging state of charge at the first time and the charging state of charge at the last time in the approximate constant current charging interval is calculated, and when the absolute value of the obtained result is greater than the charging state of charge data fluctuation threshold, the basic data corresponding to the charging state of charge data is allocated to the large SOC change charging interval;

[0021] The difference between the discharging state of charge at the first time and the discharging state of charge at the last time in the approximate constant current discharging interval is calculated, and when the absolute value of the obtained result is greater than the discharging state of charge data fluctuation threshold, the basic data corresponding to the discharging state of charge data is allocated to the large SOC change discharging interval.

[0022] The available charging capacity is represented as: C j″,N =[C r,j″ ,N] and the available discharging capacity is represented as: D k″,M =[D r,k″ ,M], wherein C j″,N is the available charging capacity expression of the jth large SOC change charging interval, C r,j″ is the available charging capacity of the jth large SOC change charging interval, represented as: i ch,t is the charging current data at time t in the jth large SOC change charging interval, is the first time in the jth large SOC change charging interval, t n″ is the last time in the jth large SOC change charging interval, is the charging state of charge data at the first time in the jth large SOC change charging interval, is the charging state of charge data at the last time in the jth large SOC change charging interval, and N is the evaluation time of the available charging capacity; D k″,M is the available discharging capacity expression of the kth large SOC change discharging interval, D r,k″ is the available discharging capacity of the kth large SOC change discharging interval, represented as: i dis,t is the discharging current data at time t in the kth large SOC change discharging interval, is the first time in the kth large SOC change discharging interval, t m″ is the last time in the kth large SOC change charging interval, is the discharge charge state data of the first time in the kth large SOC change discharge interval, is the discharge charge state data of the last time in the kth large SOC change discharge interval, and M is the evaluation time of the available discharge capacity.

[0023] The capacity degradation degree of the battery array is calculated according to the available charge capacity and the available discharge capacity, specifically: the average value of all available charge capacities in a preset period is subtracted from the average value of all available discharge capacities in the preset period to obtain an average difference value, and the average difference value is divided by the average value of all available charge capacities in the preset period to obtain the capacity degradation degree of the battery array.

[0024] The technical scheme adopted by the present application to solve its technical problems is: a kind of energy storage device battery array capacity degradation online monitoring device, comprising:

[0025] The first screening module is used to collect the basic data of the battery array, and the basic data includes current data and state of charge data, and the initial charging interval and the initial discharging interval are screened according to the current data;

[0026] The second screening module is used to screen the effective charging interval according to the charging current data of each time in the initial charging interval, and screen the effective discharging interval according to the discharging current data of each time in the initial discharging interval;

[0027] The third screening module is used to screen the approximate constant current charging interval according to the charging current data of each time in the effective charging interval, and screen the approximate constant current discharging interval according to the discharging current data of each time in the effective discharging interval;

[0028] The fourth screening module is used to screen the large SOC change charging interval according to the charging state of charge data of each time in the approximate constant current charging interval, and screen the large SOC change discharging interval according to the discharging state of charge data of each time in the approximate constant current discharging interval;

[0029] The available capacity calculation module is used to calculate the available charge capacity according to the charging current data and the charging state of charge data of the large SOC change charging interval, and calculate the available discharge capacity according to the discharging current data and the discharging state of charge data of the large SOC change discharging interval;

[0030] The capacity degradation degree calculation module is used to calculate the capacity degradation degree of the battery array according to the available charge capacity and the available discharge capacity.

[0031] The technical scheme adopted by the present application to solve its technical problems is: providing an electronic device, comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the energy storage device battery array capacity degradation online monitoring method when executing the computer program.

[0032] The technical scheme adopted by the present application to solve its technical problems is: providing a computer readable storage medium, having a computer program stored thereon, wherein the computer program is executed by a processor to implement the steps of the energy storage device battery array capacity degradation online monitoring method.

[0033] Beneficial effects

[0034] Compared with the prior art, the present application has the following advantages and positive effects: the present application can independently evaluate the available charge and discharge capacity of the battery array, improves the evaluation granularity of the energy storage device health degree, and makes the evaluation result more comprehensive and accurate. The present application proposes a capacity degradation degree index of the battery array based on the difference degree of the charge and discharge capacity, quantifies the degradation performance of the battery array, and promotes the improvement of the overall life of the energy storage device. The present application selects the charge and discharge interval with large SOC change, reduces the available capacity evaluation error caused by SOC precision. The present application uses existing collected data without increasing additional data collection cost, and has strong portability and economy. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a flowchart of the energy storage device battery array capacity degradation online monitoring method of the first embodiment of the present application;

[0036] Figure 2 is a schematic diagram of the calculation results of the charge capacity and the discharge capacity in the embodiment of the present application. DETAILED DESCRIPTION

[0037] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. In addition, it should be understood that those skilled in the art can make various modifications or changes to the present application after reading the content taught by the present application, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

[0038] The first embodiment of the present application relates to an energy storage device battery array capacity degradation online monitoring method, as shown in Figure 1 , comprising the following steps:

[0039] Step 1, collecting the basic data A of the battery array t , the basic data A t including current data i t and state of charge data St and according to the current data i t Screening initial charging interval A ch,t and initial discharging interval A dis,t . Wherein, the basic data A t of the battery array can be expressed as: A t = [i t , S t ], when screening, if the basic data with current data less than 0 is allocated to the initial charging interval, and the basic data with current data greater than 0 is allocated to the initial discharging interval, that is, when i t <0, it means that the battery array is charging, and it is marked as C t = [i ch,t , S ch,t ], and added to the initial charging interval A ch,t , when i t >0, it means that the battery array is discharging, and it is marked as D t = [i dis,t , S dis,t ], and added to the initial discharging interval A dis,t .

[0040] Step 2, according to the charging current data of each time in the initial charging interval A ch,t , the effective charging interval is screened out, and according to the discharging current data of each time in the initial discharging interval A dis,t , the effective discharging interval is screened out.

[0041] In this step, when screening the effective charging interval, the charging current data i ch,t of each time in the initial charging interval A ch,t is compared with the charging current screening threshold i ch,int (i ch,int ≥0) respectively, the basic data with the absolute value of the charging current data greater than or equal to the charging current screening threshold is allocated to the effective charging interval, that is, when |i ch,t |≥i ch,int , it is considered that the charging current data i ch,t corresponding basic data C t = [i ch,t , S ch,t ] belongs to the effective charging interval, so it is added to the effective charging interval. Wherein, the jth effective charging interval segment can be marked as Wherein, and are the charging current data at the first time t1 and the last time t n of the jth effective charging interval respectively, and respectively, are the charge state of charge data at the first time t1 and the last time t n respectively, of the jth effective discharge interval.

[0042] In this step, when screening the effective discharge interval, the discharge current data i dis,t at each time in the initial discharge interval A dis,t is compared with the discharge current threshold i dis,int (i dis,int ≥ 0), and the basic data with discharge current data greater than or equal to the discharge current threshold is assigned to the effective discharge interval, that is, when i dis,t ≥ i dis,int , the discharge current data i dis,t is considered to correspond to the basic data D t = [i dis,t , S dis,t ] belonging to the effective discharge interval, and thus it is added to the effective discharge interval. The kth effective discharge interval segment can be marked as wherein, and are the discharge current data at the first time t1 and the last time t m of the kth effective discharge interval respectively, and are the discharge state of charge data at the first time t1 and the last time t m of the kth effective discharge interval respectively.

[0043] Step 3, according to the charging current data at each time in the effective charging interval, the approximately constant current charging interval is screened out, and according to the discharge current data at each time in the effective discharge interval, the approximately constant current discharge interval is screened out.

[0044] In this step, when screening the approximately constant current charging interval, the difference between the charging current i at the first time and the charging current i ch,n at the nth time in the effective charging interval is calculated, and the difference is divided by the charging current i at the first time. When the absolute value of the result is less than or equal to the charging current fluctuation threshold Δi ch (0 < Δi ch < 1), the basic data corresponding to the charging current data is assigned to the approximately constant current charging interval. Taking the fourth time charging current data in the effective charging interval as an example, when the basic data corresponding to the fourth time charging current data D is added to the approximately constant current charging interval; when The charging current data at the fourth moment is then used as the starting point of the next effective charging interval, and the above calculations are performed on it, thus obtaining multiple approximate constant current charging intervals. The j′-th approximate constant current charging interval is marked as... in, and These are the first moments of the j'th approximately constant current charging interval. Charging current data at time t and the last time t n' Charging current data at that time, and These are the first moments of the j′-th approximate constant current charging interval. State of charge data at time t and the last time t n' The state of charge data at that time.

[0045] In this step, when selecting the approximate constant current discharge range, the discharge current at the first moment in the effective discharge range is calculated. The discharge current i at time n dis,n The difference is calculated and then divided by the discharge current at the first moment. When the absolute value of the obtained result is less than or equal to the discharge current fluctuation threshold Δi dis (0<Δi dis If <1), then the basic data corresponding to the discharge current data is allocated to the approximate constant current discharge interval. Taking the calculation of the discharge current data at the fourth moment in the effective discharge interval as an example, when The basic data corresponding to the discharge current data at the fourth moment. When added to the approximate constant current discharge range, Using the discharge current data at the fourth moment as the starting point of the next effective discharge interval, and performing the above calculations, multiple approximate constant current discharge intervals can be obtained. The k′-th approximate constant current discharge interval is marked as... in, and These are the first moments of the k′-th approximate constant current discharge interval. Charging current data at time t and the last time t m' Charging current data at that time, and These are the first moments of the k′-th approximate constant current discharge interval. Discharge state data at time t and the last time t m′ Data on the charge state at that time.

[0046] Step 4, screening out large SOC change charging intervals according to charging state of charge data at each time in the approximate constant current charging interval, and screening out large SOC change discharging intervals according to discharging state of charge data at each time in the approximate constant current discharging interval.

[0047] In this step, when screening out large SOC change charging intervals, the difference between the charging state of charge data at the first time in the approximate constant current charging interval and the charging state of charge data at the last time is calculated. When the absolute value of the result is greater than the charging state of charge data fluctuation threshold ΔS ch , the basic data corresponding to the charging state of charge data is allocated to the large SOC change charging interval. Taking the charging state of charge data at the first time in the approximate constant current charging interval as an example, when the basic data corresponding to the charging state of charge data at the first time is added to the large SOC change charging interval. Wherein, the jth large SOC change charging interval is marked as Wherein, and are the charging current data at the first time and the charging current data at the last time t n” in the jth large SOC change charging interval segment, respectively. and are the state of charge data at the first time and the state of charge data at the last time t n” in the jth large SOC change charging interval, respectively.

[0048] In screening out large SOC change discharging intervals, the difference between the discharging state of charge data at the first time in the approximate constant current discharging interval and the discharging state of charge data at the last time is calculated. When the absolute value of the result is greater than the discharging state of charge data fluctuation threshold ΔS dis (0 < ΔS dis < 1), the basic data corresponding to the discharging state of charge data is allocated to the large SOC change discharging interval. Taking the discharging state of charge data at the first time in the approximate constant current charging interval as an example, when the basic data corresponding to the discharging state of charge data at the first time is added to the large SOC change discharging interval. Wherein, the kth large SOC change discharging interval is marked as Wherein, and are the discharging current data at the first time and the discharging current data at the last time t in the kth large SOC change discharging interval segment, respectively.​​​​​​m” Discharge current data at that time and These are the first moments of the k”th large SOC change discharge interval. Discharge state data at time t and the last time t m” Data on the charge state at that time.

[0049] Step 5: Calculate the available charging capacity based on the charging current data and state of charge data of the large SOC variation charging range, and calculate the available discharge capacity based on the discharge current data and state of charge data of the large SOC variation discharging range.

[0050] In this step, the available charging capacity of the j”th large SOC variation charging range is represented as: C j″,N =[C r,j″ [,N], where,,C j″,N Let C be the expression for the available charging capacity during the j″-th large SOC variation charging range. r,j″ The available charging capacity for the j″-th large SOC variation charging range is expressed as: N is the evaluation time for available charging capacity, and N = t″ n This is the last moment of the j″-th large SOC change charging interval.

[0051] The discharge capacity of the k″-th large SOC variation discharge interval can be represented by: D k″,M =[D r,k″ [,M], where D k″,M Let D be the expression for the available discharge capacity in the k″-th large SOC variation discharge interval. r,k″ The available discharge capacity for the k″-th large SOC variation discharge interval is expressed as: M is the assessment time for available discharge capacity, and M = t″ m This is the last moment of the k″-th large SOC change discharge interval.

[0052] Step 6: Calculate the capacity degradation of the battery array based on the available charging capacity and available discharging capacity.

[0053] In this step, the capacity degradation η of the battery array is... ΔT The calculation is performed according to a certain time period, and the calculation method is as follows:

[0054]

[0055] Where T is the last moment in the cycle, x is the number of available charging capacities in the cycle, and AVE(C x ) represents the average of x available charging capacities within this cycle, and y represents the number of available discharging capacities within this cycle. AVE(D)y ) is the average value of y available discharge capacities in the cycle.

[0056] The following is the evaluation result of the available charge and discharge capacities of the fixed energy storage device battery array. A total of 201 charge intervals and 192 discharge intervals are screened out, and the calculation results of the charge and discharge capacities are shown in Figure 2 According to the calculation results, the initial capacity of the battery is about 480 Ah, and the battery capacity decays as the battery ages. In the later stage of battery aging, the charge and discharge performance of the battery becomes unstable, and the charge and discharge capacity of the battery fluctuates between 250-350 Ah, and finally decays to 300 Ah. The charge and discharge capacities of the battery array are more dispersed, and the capacity degradation degree gradually increases.

[0057] It can be found that the present application can independently evaluate the available charge and discharge capacities of the battery array, improve the evaluation granularity of the energy storage device health, and make the evaluation result more comprehensive and accurate. The present application proposes a capacity degradation degree index of the battery array based on the difference degree of the charge and discharge capacities, quantifies the degradation performance of the battery array, and promotes the improvement of the overall life of the energy storage device. The present application selects the charge and discharge intervals with large SOC changes, reduces the available capacity evaluation error caused by the SOC precision. The present application uses the existing collected data, does not increase the additional data collection cost, and has strong portability and economy.

[0058] The second embodiment of the present application relates to an energy storage device battery array capacity degradation online monitoring device, comprising:

[0059] A first screening module is used to collect the basic data of the battery array, the basic data including current data and state of charge data, and to screen the initial charge interval and the initial discharge interval according to the current data;

[0060] A second screening module is used to screen the effective charge interval according to the charge current data at each time in the initial charge interval, and to screen the effective discharge interval according to the discharge current data at each time in the initial discharge interval;

[0061] A third screening module is used to screen the approximately constant current charge interval according to the charge current data at each time in the effective charge interval, and to screen the approximately constant current discharge interval according to the discharge current data at each time in the effective discharge interval;

[0062] A fourth screening module is used to screen the large SOC change charge interval according to the charge state of charge data at each time in the approximately constant current charge interval, and to screen the large SOC change discharge interval according to the discharge state of charge data at each time in the approximately constant current discharge interval;

[0063] The available capacity calculation module is configured to calculate available charging capacity according to charging current data and charging state of charge data of a large SOC change charging interval, and calculate available discharging capacity according to discharging current data and discharging state of charge data of a large SOC change discharging interval.

[0064] The capacity degradation degree calculation module is configured to calculate a capacity degradation degree of the battery array according to the available charging capacity and the available discharging capacity.

[0065] The first screening module is configured to, when screening the initial charging interval and the initial discharging interval according to the current data, assign the basic data with current data less than 0 to the initial charging interval, and assign the basic data with current data greater than 0 to the initial discharging interval.

[0066] The second screening module comprises:

[0067] The effective charging interval screening unit is configured to compare the charging current data at each time point in the initial charging interval with a charging current screening threshold respectively, and assign the basic data with the absolute value of the charging current data greater than or equal to the charging current screening threshold to the effective charging interval.

[0068] The effective discharging interval screening unit is configured to compare the discharging current data at each time point in the initial discharging interval with a discharging current threshold respectively, and assign the basic data with the discharging current data greater than or equal to the discharging current threshold to the effective discharging interval.

[0069] The third screening module comprises:

[0070] The third screening module is configured to calculate a difference value between the charging current at the first time point and the charging current at the nth time point in the effective charging interval, and divide the difference value by the charging current at the first time point, when the absolute value of the obtained result is less than or equal to a charging current fluctuation threshold, assign the basic data corresponding to the charging current to the approximately constant current charging interval, and when the absolute value of the obtained result is greater than the charging current fluctuation threshold, take the charging current at the nth time point as a start time point of the next effective charging interval.

[0071] The third screening module is configured to calculate a difference value between the discharging current at the first time point and the discharging current at the nth time point in the effective discharging interval, and divide the difference value by the discharging current at the first time point, when the absolute value of the obtained result is less than or equal to a discharging current fluctuation threshold, assign the basic data corresponding to the discharging current data to the approximately constant current discharging interval, and when the absolute value of the obtained result is greater than the discharging current fluctuation threshold, take the charging current at the nth time point as a start time point of the next effective discharging interval.

[0072] The fourth screening module comprises:

[0073] The large SOC change charging interval screening unit is configured to calculate a difference between a charging state of charge at a first time and a charging state of charge at a last time in an approximately constant current charging interval, and when an absolute value of a result obtained is greater than a charging state of charge data fluctuation threshold, the basic data corresponding to the charging state of charge data is allocated to the large SOC change charging interval.

[0074] The large SOC change discharging interval screening unit is configured to calculate a difference between a discharging state of charge at a first time and a discharging state of charge at a last time in an approximately constant current discharging interval, and when an absolute value of a result obtained is greater than a discharging state of charge data fluctuation threshold, the basic data corresponding to the discharging state of charge data is allocated to the large SOC change discharging interval.

[0075] The available charging capacity is represented as: C j″,N = [C r,j″ , N], and the available discharging capacity is represented as: D k″,M = [D r,k″ , M], wherein C j″,N is an available charging capacity expression of the jth large SOC change charging interval, C r,j″ is an available charging capacity of the jth large SOC change charging interval, and is represented as: i ch,t is charging current data at t in the jth large SOC change charging interval, is a first time in the jth large SOC change charging interval, t n″ is a last time in the jth large SOC change charging interval, is charging state of charge data at the first time in the jth large SOC change charging interval, is charging state of charge data at the last time in the jth large SOC change charging interval, and N is an evaluation time of the available charging capacity. k″,M D r,k″ is an available discharging capacity expression of the kth large SOC change discharging interval, D r,k″ is an available discharging capacity of the kth large SOC change discharging interval, and is represented as: i dis,t is discharging current data at t in the kth large SOC change discharging interval, is a first time in the kth large SOC change discharging interval, t m″ is a last time in the kth large SOC change charging interval, is discharging state of charge data at the first time in the kth large SOC change discharging interval, is discharging state of charge data at the last time in the kth large SOC change discharging interval, and M is an evaluation time of the available discharging capacity.

[0076] The capacity degradation degree calculation module calculates the capacity degradation degree of the battery array according to the available charging capacity and the available discharging capacity by subtracting the average of all available discharging capacities in the preset period from the average of all available charging capacities in the preset period, and then dividing the average difference by the average of all available charging capacities in the preset period.

[0077] The third embodiment of the present application relates to an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the capacity degradation online monitoring method of the battery array of the energy storage device of the first embodiment when executing the computer program.

[0078] The fourth embodiment of the present application relates to a computer readable storage medium, which stores a computer program, wherein the computer program implements the steps of the capacity degradation online monitoring method of the battery array of the energy storage device of the first embodiment when executed by a processor.

[0079] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage, etc.) containing computer-usable program code.

[0080] The present application is described with reference to the flowcharts and / or block diagrams according to the methods, devices (systems), and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one flow or multiple flows and / or blocks Figure 1 The means for implementing the functions specified in one flow or multiple flows and / or blocks.

[0081] These computer program instructions can also be stored in a computer-readable memory capable of guiding the computer or other programmable data processing devices to work in a specific manner, so that the instructions stored in the computer-readable memory produce a product comprising an instruction method, which implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one flow or multiple flows and / or blocks Figure 1the function specified in the one or more blocks.

[0082] These computer program instructions can also be loaded into computer or other programmable data processing devices, so that a series of operation steps are performed on the computer or other programmable data processing devices to generate computer-implemented processes, so that the instructions executed on the computer or other programmable data processing devices provide processes for implementing the flows Figure 1 the flow or flows and / or blocks Figure 1 the steps of the function specified in the one or more blocks.

[0083] The above description is merely one specific implementation of the application, but the protection scope of the application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the application, which should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. An energy storage device battery array capacity degradation on-line monitoring method, characterized in that, The method comprises the following steps: Collecting basic data of the battery array, the basic data comprising current data and state of charge data, and screening an initial charging interval and an initial discharging interval according to the current data; Screening an effective charging interval according to the charging current data at each time in the initial charging interval, and screening an effective discharging interval according to the discharging current data at each time in the initial discharging interval; Screening an approximately constant-current charging interval according to the charging current data at each time in the effective charging interval, and screening an approximately constant-current discharging interval according to the discharging current data at each time in the effective discharging interval; Screening a large-SOC-change charging interval according to the charging state of charge data at each time in the approximately constant-current charging interval, and screening a large-SOC-change discharging interval according to the discharging state of charge data at each time in the approximately constant-current discharging interval; Calculating available charging capacity according to the charging current data and the charging state of charge data of the large-SOC-change charging interval, and calculating available discharging capacity according to the discharging current data and the discharging state of charge data of the large-SOC-change discharging interval; Calculating the capacity degradation degree of the battery array according to the available charging capacity and the available discharging capacity.

2. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The screening of the initial charging interval and the initial discharging interval according to the current data is specifically: allocating the basic data with current data less than 0 to the initial charging interval, and allocating the basic data with current data greater than 0 to the initial discharging interval.

3. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The screening of the effective charging interval according to the charging current data at each time in the initial charging interval, and the screening of the effective discharging interval according to the discharging current data at each time in the initial discharging interval are specifically: Comparing the charging current data at each time in the initial charging interval with a charging current screening threshold value respectively, and allocating the basic data with the absolute value of the charging current data greater than or equal to the charging current screening threshold value to the effective charging interval; Comparing the discharging current data at each time in the initial discharging interval with a discharging current threshold value respectively, and allocating the basic data with the discharging current data greater than or equal to the discharging current threshold value to the effective discharging interval.

4. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The screening of the approximately constant-current charging interval according to the charging current data at each time in the effective charging interval, and the screening of the approximately constant-current discharging interval according to the discharging current data at each time in the effective discharging interval are specifically: Calculating the difference between the charging current at the first time and the charging current at the nth time in the effective charging interval, and dividing the difference by the charging current at the first time, when the absolute value of the result is less than or equal to a charging current fluctuation threshold value, the basic data corresponding to the charging current at the nth time is allocated to the approximately constant-current charging interval; When the absolute value of the result is greater than the charging current fluctuation threshold value, the charging current at the nth time is taken as the starting time point of the next effective charging interval; Calculating the difference between the discharging current at the first time and the discharging current at the nth time in the effective discharging interval, and dividing the difference by the discharging current at the first time, when the absolute value of the result is less than or equal to a discharging current fluctuation threshold value, the basic data corresponding to the discharging current at the nth time is allocated to the approximately constant-current discharging interval; When the absolute value of the result is greater than the discharge current fluctuation threshold, the discharge current at the nth moment is taken as the starting moment of the next effective charging interval.

5. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The method further includes: screening a large SOC change charging interval according to the charging state of charge data at each moment in the approximate constant current charging interval, and screening a large SOC change discharging interval according to the discharging state of charge data at each moment in the approximate constant current discharging interval, and specifically including: The difference between the charging state of charge at the first moment and the charging state of charge at the last moment in the approximate constant current charging interval is calculated, and when the absolute value of the result is greater than the charging state of charge data fluctuation threshold, the basic data corresponding to the charging state of charge data is allocated to the large SOC change charging interval. The difference between the discharging state of charge at the first moment and the discharging state of charge at the last moment in the approximate constant current discharging interval is calculated, and when the absolute value of the result is greater than the discharging state of charge data fluctuation threshold, the basic data corresponding to the discharging state of charge data is allocated to the large SOC change discharging interval.

6. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The available charge capacity is represented as: C j″,N = [C r,j″ , N], and the available discharge capacity is represented as: D k″,M = [D r,k″ , M], wherein C j″,N is an available charge capacity expression of the jth large SOC change charging interval, C r,j″ is the available charge capacity of the jth large SOC change charging interval, represented as: i ch,t is the charging current data at time t in the jth large SOC change charging interval, is the first time in the jth large SOC change charging interval, t n″ is the last time in the jth large SOC change charging interval, is the charge state of charge data at the first time in the jth large SOC change charging interval, is the charge state of charge data at the last time in the jth large SOC change charging interval, and N is the evaluation time of the available charge capacity; D k″,M is an available discharge capacity expression of the kth large SOC change discharging interval, D r,k″ is the available discharge capacity of the kth large SOC change discharging interval, represented as: i dis,t is the discharging current data at time t in the kth large SOC change discharging interval, is the first time in the kth large SOC change discharging interval, t m″ is the last time in the kth large SOC change charging interval, is the discharge state of charge data at the first time in the kth large SOC change discharging interval, is the discharge state of charge data at the last time in the kth large SOC change discharging interval, and M is the evaluation time of the available discharge capacity.

7. The energy storage device battery array capacity degradation on-line monitoring method of claim 1, wherein, The method further includes: calculating the capacity degradation degree of the battery array according to the available charging capacity and the available discharging capacity, and specifically including: subtracting the average of all available discharging capacities in the preset period from the average of all available charging capacities in the preset period to obtain an average difference, and then dividing the average difference by the average of all available charging capacities in the preset period to obtain the capacity degradation degree of the battery array.

8. An energy storage device battery array capacity degradation on-line monitoring apparatus, characterized by, The method further includes: The first screening module is configured to collect basic data of the battery array, the basic data including current data and state of charge data, and screen an initial charging interval and an initial discharging interval according to the current data. The second screening module is configured to screen an effective charging interval according to the charging current data at each moment in the initial charging interval, and screen an effective discharging interval according to the discharging current data at each moment in the initial discharging interval. The third screening module is configured to screen an approximate constant current charging interval according to the charging current data at each moment in the effective charging interval, and screen an approximate constant current discharging interval according to the discharging current data at each moment in the effective discharging interval. The fourth screening module is configured to screen a large SOC change charging interval according to the charging state of charge data at each moment in the approximate constant current charging interval, and screen a large SOC change discharging interval according to the discharging state of charge data at each moment in the approximate constant current discharging interval. The available capacity calculation module is configured to calculate the available charging capacity according to the charging current data and the charging state of charge data of the large SOC change charging interval, and calculate the available discharging capacity according to the discharging current data and the discharging state of charge data of the large SOC change discharging interval. The capacity degradation degree calculation module is configured to calculate the capacity degradation degree of the battery array according to the available charging capacity and the available discharging capacity.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the steps of the energy storage device battery array capacity degradation online monitoring method in any one of claims 1-7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the energy storage device battery array capacity degradation online monitoring method in any one of claims 1-7.

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