A power equipment capacity analysis method and system

Abstract

The application discloses a kind of power equipment capacity analysis method and system, method includes: determining target discharge current variation sequence between target time and current time, and at least one target historical discharge current variation sequence is selected in each historical discharge current variation sequence according to target discharge current variation sequence;At least one target historical calibration capacity that exists associated relationship with at least one target historical discharge current variation sequence is found, and the current loss capacity of power equipment between target time and current time is determined using preset capacity matching rule;Current calibration capacity in current discharge cycle is determined based on the initial calibration capacity of power equipment;Based on current calibration capacity and current loss capacity, the residual capacity of power equipment at current time is determined using preset capacity analysis strategy.Thereby the accuracy of determining the residual battery capacity of power equipment at current time is improved as far as possible.

Description

A method and system for capacity analysis of power equipment Technical Field

[0001] This invention belongs to the field of capacity analysis technology, and in particular relates to a method and system for capacity analysis of power equipment. Background Technology

[0002] In the field of power equipment management, particularly in capacity status assessment of energy storage devices such as batteries, numerous technical challenges have persisted. Firstly, traditional capacity assessment methods cannot effectively address dynamically changing discharge conditions. In actual operation, power equipment often operates in environments with frequent load fluctuations, resulting in complex non-stationary characteristics in the discharge current. While existing technologies such as the ampere-hour integration method are computationally simple, they lack the ability to identify current variation patterns, leading to significant deviations in capacity assessment results under different discharge scenarios. Especially when equipment experiences variable current discharge, traditional methods struggle to accurately establish the correlation between current changes and capacity decay.

[0003] Secondly, existing technologies lack precise methods for quantifying capacity degradation during equipment aging. As the number of cycles increases, the actual usable capacity of power equipment gradually decreases, but traditional assessment methods often rely on fixed capacity degradation models, which cannot adapt to the individualized degradation characteristics under different operating conditions. This leads to inaccurate equipment health status assessments, affects the reliability of remaining life predictions, and creates difficulties for equipment maintenance and replacement decisions. Summary of the Invention

[0004] This invention provides a method and system for analyzing the capacity of power equipment, which solves the technical problem of inaccurate estimation of the remaining capacity of power equipment.

[0005] In a first aspect, the present invention provides a method for analyzing the capacity of power equipment, comprising:

[0006] The historical rated capacity of the power equipment in each historical discharge cycle is obtained, as well as the historical discharge current change sequence corresponding to each historical discharge cycle, and the correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle is established.

[0007] Determine the target discharge current change sequence from the target time to the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence;

[0008] Find at least one target historical calibration capacity that is correlated with the at least one target historical discharge current change sequence, and determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule;

[0009] The current rated capacity of the power equipment is determined based on the initial rated capacity of the power equipment in the current discharge cycle, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time;

[0010] Based on the current rated capacity and the current lost capacity, a preset capacity analysis strategy is used to determine the remaining capacity of the power equipment at the current moment.

[0011] Furthermore, the historical discharge period is the time period from the start of discharge to the end of discharge, and a certain historical discharge current change sequence contains historical discharge currents sorted by time within a certain historical discharge period.

[0012] Furthermore, the target time is the discharge start time that has the shortest interval with the current time;

[0013] The step of selecting at least one target historical discharge current change sequence from various historical discharge current change sequences based on the target discharge current change sequence includes:

[0014] In the target discharge current change sequence, at least one discharge current with the same current value is extracted sequentially according to the time sequence, and each extraction yields a target discharge current change subsequence. Each target discharge current change subsequence is then assigned to a target subsequence set.

[0015] Each historical discharge current change sequence is further truncated to obtain at least one set of historical discharge current change subsequences.

[0016] Determine whether there exists at least one target historical discharge current change subsequence set that is the same as the target subsequence set in the at least one historical discharge current change subsequence set. If the subsequence length and current value of each target historical discharge current change subsequence in a target historical discharge current change subsequence set are the same as the subsequence length and current value of each target discharge current change subsequence in the target subsequence set, then the target subsequence set is determined to be the same as the target historical discharge current change subsequence set.

[0017] If there exists at least one target historical discharge current change subsequence set that is identical to the target subsequence set, then the target historical discharge current change sequence corresponding to the at least one target historical discharge current change subsequence set is selected.

[0018] Furthermore, after determining whether there exists at least one target historical discharge current change subsequence set that is identical to the target subsequence set in the at least one set of historical discharge current change subsequences, the method further includes:

[0019] If there is no target historical discharge current change subsequence set that is the same as the target subsequence set, then determine whether there is a combination of at least one historical discharge current change subsequence set that includes the target subsequence set;

[0020] If there exists at least one set of historical discharge current change subsequences that includes the target subsequence set, then the set of historical discharge current change subsequences with the smallest number of sequences is selected from the at least one set of historical discharge current change subsequences, and the historical discharge current change sequence corresponding to each set of historical discharge current change subsequences in the set of historical discharge current change subsequences is defined as the first historical discharge current change sequence.

[0021] Based on the aforementioned correlation, the first calibration capacity corresponding to each first historical discharge current change sequence is obtained, and the first calibration capacities are added together to obtain the total calibration capacity.

[0022] The current loss capacity of the power equipment between the target time and the current time is determined based on the total rated capacity and the first sequence length ratio, wherein the first sequence length ratio is the ratio of the sequence length of the target discharge current change sequence to the sum of the sequence lengths of each first historical discharge current change sequence.

[0023] Furthermore, after determining whether there exists a combination of at least one set of historical discharge current change subsequences containing the target subsequence set, the method further includes:

[0024] If there is no set of at least one historical discharge current change subsequences that includes the target subsequence set, then a historical discharge current change sequence that has the same current change as a target discharge current change subsequence is assigned to the second discharge current change sequence set, wherein a historical discharge current change subsequence of the target discharge current change sequence has the same current change as a target discharge current change subsequence.

[0025] Further, the step of finding at least one target historical calibration capacity that is correlated with the at least one target historical discharge current change sequence, and determining the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule, includes:

[0026] Based on the chronological order, at least one target historical discharge current with the same current value is extracted from the at least one target historical discharge current change sequence. Each extraction yields a target historical discharge current change subsequence, and finally, a set of target historical discharge current change subsequences corresponding to the at least one target historical discharge current change sequence is obtained.

[0027] The number of subsequences in the set of subsequences of historical discharge current changes for each target is defined as the first subsequence number, and the number of subsequences in the set of subsequences of the target is defined as the second subsequence number.

[0028] Select the first target subsequence number with the smallest difference from the second subsequence number among the various first subsequence numbers, and obtain the first target historical discharge current change sequence corresponding to the first target subsequence number;

[0029] Based on the correlation, obtain the first battery calibration capacity corresponding to the historical discharge current change sequence of the first target;

[0030] The current loss capacity of the power equipment between the target time and the current time is determined based on the first battery rated capacity and the second sequence length ratio, wherein the second sequence length ratio is the ratio between the sequence length of the target discharge current change sequence and the sequence length of the first target historical discharge current change sequence.

[0031] Further, determining the current rated capacity in the current discharge cycle based on the initial rated capacity of the power equipment includes:

[0032] The first polarization internal resistance of the power equipment in the first discharge cycle is obtained, wherein the first discharge cycle is the discharge time cycle adjacent to the current discharge cycle;

[0033] Obtain the initial polarization internal resistance of the power equipment after the first cycle, and calculate the internal resistance ratio between the initial polarization internal resistance and the first polarization internal resistance;

[0034] The current rated capacity of the power equipment in the current discharge time period is calculated based on the initial rated capacity and the internal resistance ratio.

[0035] In a second aspect, the present invention provides a power equipment capacity analysis system, comprising:

[0036] The acquisition module is configured to acquire the historical rated capacity of the power equipment in each historical discharge cycle, as well as the historical discharge current change sequence corresponding to each historical discharge cycle, and establish the correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle.

[0037] The selection module is configured to determine the target discharge current change sequence from the target time to the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence according to the target discharge current change sequence.

[0038] The matching module is configured to find at least one target historical calibration capacity that is associated with the at least one target historical discharge current change sequence, and to determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule;

[0039] The determination module is configured to determine the current calibration capacity in the current discharge cycle based on the initial calibration capacity of the power equipment, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time;

[0040] The analysis module is configured to determine the remaining capacity of the power equipment at the current moment based on the current calibrated capacity and the current lost capacity, using a preset capacity analysis strategy.

[0041] The power equipment capacity analysis method and system of this application constructs a complete capacity analysis database by establishing the correlation between historical discharge current sequences and rated capacity. It then employs a multi-level matching strategy between the target sequence and historical sequences, including three modes: complete matching, combined matching, and sub-sequence matching, ensuring reliable matching results under varying data completeness conditions. Through accurate identification of current change patterns and dynamic sub-sequence segmentation technology, it effectively solves the problem of poor adaptability of traditional methods under variable load conditions. Combining the correlation characteristics between polarization resistance changes and capacity decay, it achieves a relatively accurate estimation of the current rated capacity. Finally, by integrating the current rated capacity and lost capacity through the capacity analysis strategy, it obtains an accurate assessment of remaining capacity. While maintaining the simplicity of system implementation, it significantly improves the accuracy and reliability of capacity analysis, providing strong technical support for intelligent operation and maintenance and life prediction of power equipment. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 is a flowchart of a power equipment capacity analysis method according to an embodiment of the present invention;

[0044] Figure 2 is a structural block diagram of a power equipment capacity analysis system provided in an embodiment of the present invention;

[0045] Figure 3 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Please refer to Figure 1, which shows a flowchart of a power equipment capacity analysis method according to this application.

[0048] As shown in Figure 1, the power equipment capacity analysis method specifically includes the following steps:

[0049] Step S101: Obtain the historical rated capacity of the power equipment in each historical discharge cycle, and the historical discharge current change sequence corresponding to each historical discharge cycle, and establish the correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle.

[0050] In this step, electrical equipment specifically refers to rechargeable batteries used in power systems, new energy storage, or backup power sources, such as lithium-ion batteries, lead-acid batteries, and nickel-metal hydride batteries.

[0051] Specifically, historical rated capacity refers to the actual usable capacity (usually measured in ampere-hours (Ah) or kilowatt-hours (kWh)) of a power device obtained through actual testing or calibration during each complete discharge cycle in the past. For example, for a battery, rated capacity refers to the total amount of electricity released when discharged from a fully charged state to the cutoff voltage under standard discharge conditions (such as specific temperature and discharge rate). Capacity data of power devices over multiple historical discharge cycles is collected through a battery management system (BMS), supervisory control and data acquisition system (SCADA), or monitoring platform. This data may come from periodically performed capacity calibration tests (such as full discharge tests) or daily operating records.

[0052] The historical discharge cycle is the time period from the start of discharge to the end of discharge. A certain historical discharge current change sequence contains the historical discharge currents sorted by time within a certain historical discharge cycle.

[0053] A historical discharge current variation sequence refers to the sequence data of how the discharge current changes over time within each historical discharge cycle. Each data point in the sequence represents the discharge current value at a specific point in time, arranged in chronological order. The sequence can reflect characteristics such as current fluctuations and load changes during the discharge process. For example, high-precision current sensors (such as Hall effect sensors or shunts) can be used to monitor the discharge current of power equipment in real time, and the current values ​​can be recorded at fixed sampling intervals (such as per second, per minute, or as set according to application requirements).

[0054] For each historical discharge cycle, a historical discharge current change sequence is generated, and the sequence length depends on the discharge duration.

[0055] Step S102: Determine the target discharge current change sequence between the target time and the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence according to the target discharge current change sequence.

[0056] In this step, step S102 specifically performs the following sub-steps:

[0057] Step S1021: The target time is the discharge start time with the shortest interval from the current time.

[0058] Specifically, in the target discharge current change sequence, at least one discharge current with the same current value is extracted sequentially based on the time sequence, and each extraction yields a target discharge current change subsequence. Each target discharge current change subsequence is then assigned to a target subsequence set.

[0059] In one specific embodiment, the target discharge current change sequence is (0.2A, 0.3A, 0.3A, 0.3A, 0.4A, 0.2A, 0.1A, 0.1A, 0.1A). Then, by extracting at least one discharge current with the same current value from the target discharge current change sequence, we can obtain the target discharge current change subsequences a (0.2A), b (0.3A, 0.3A, 0.3A), c (0.4A), d (0.2A), and e (0.1A, 0.1A, 0.1A), which together form the target discharge current change subsequence set.

[0060] Step S1022: Extract each historical discharge current change sequence again to obtain at least one set of historical discharge current change subsequences.

[0061] In another specific embodiment, at least one historical discharge current with the same current value in the historical discharge current change sequence (0.2A, 0.3A, 0.3A, 0.4A, 0.4A, 0.2A, 0.2A, 0.1A, 0.1A) is extracted to obtain historical discharge current change subsequences a1 (0.2A), b1 (0.3A, 0.3A), c1 (0.4A, 0.4A), d1 (0.2A, 0.2A), and e1 (0.1A, 0.1A), which constitute the first set of discharge current change subsequences.

[0062] Step S1023: Determine whether there exists at least one target historical discharge current change subsequence set that is the same as the target subsequence set in at least one historical discharge current change subsequence set. If the subsequence length and current value of each target historical discharge current change subsequence in the target historical discharge current change subsequence set are the same as the subsequence length and current value of each target discharge current change subsequence in the target subsequence set, then the target subsequence set is determined to be the same as a certain target historical discharge current change subsequence set.

[0063] In this embodiment, it is assumed that the target discharge current change sequence is (0.2A, 0.3A, 0.3A, 0.3A, 0.4A, 0.2A, 0.1A, 0.1A, 0.1A), the first historical discharge current change sequence is (0.2A, 0.3A, 0.3A, 0.4A, 0.4A, 0.2A, 0.2A, 0.1A, 0.1A), and the second historical discharge current change sequence is (0.2A, 0.3A, 0.3A, 0.3A, 0.4A, 0.2A, 0.1A, 0.1A, 0.1A).

[0064] Then, by extracting the target discharge current change sequence, the first historical discharge current change sequence, and the second historical discharge current change sequence respectively, we obtain the target discharge current change subsequence set, the first historical discharge current change subsequence set, and the second historical discharge current change subsequence set. The second historical discharge current change subsequence set is the same as the target subsequence set.

[0065] Step S1024: If there exists at least one target historical discharge current change subsequence set that is the same as the target subsequence set, then select the target historical discharge current change sequence corresponding to the at least one target historical discharge current change subsequence set.

[0066] Step S1025: If there is no target historical discharge current change subsequence set that is the same as the target subsequence set, then determine whether there is a combination of at least one historical discharge current change subsequence set that includes the target subsequence set.

[0067] The combination of historical discharge current change subsequences is a combination of at least two historical discharge current change subsequences, and the at least two historical discharge current change subsequences can completely cover the target subsequence set.

[0068] For example, the target subsequence set contains target discharge current change subsequence a (0.2A, 0.2A), target discharge current change subsequence b (0.3A, 0.3A), target discharge current change subsequence c (0.4A), target discharge current change subsequence d (0.2A), and target discharge current change subsequence e (0.1A, 0.1A, 0.1A).

[0069] The first set of historical discharge current change subsequences includes historical discharge current change subsequences a1 (0.2A, 0.2A), b1 (0.3A, 0.3A), c1 (0.4A), d1 (0.2A, 0.2A), e1 (0.1A, 0.1A), and f1 (0.2A, 0.2A).

[0070] The second set of historical discharge current change subsequences includes historical discharge current change subsequences a2 (0.2A), b2 (0.3A, 0.3A, 0.3A), c2 (0.4A), d2 (0.2A), e2 (0.1A, 0.1A, 0.1A), and f2 (0.2A).

[0071] The third set of historical discharge current change subsequences includes historical discharge current change subsequences a3 (0.2A, 0.2A), b3 (0.3A, 0.3A), c3 (0.4A, 0.4A), and d3 (0.1, 0.1A, 0.1A).

[0072] Therefore, the combinations of historical discharge current change subsequence sets containing the target subsequence set are (first historical discharge current change subsequence set + second historical discharge current change subsequence set) and (first historical discharge current change subsequence set + second historical discharge current change subsequence set + third historical discharge current change subsequence set).

[0073] If there exists at least one combination of historical discharge current change subsequence sets containing the target subsequence set, then the combination of historical discharge current change subsequence sets with the smallest number of sequences is selected from the at least one combination of historical discharge current change subsequence sets, and the historical discharge current change sequence corresponding to each historical discharge current change subsequence set in the combination of historical discharge current change subsequence sets is defined as the first historical discharge current change sequence.

[0074] Specifically, the combination of the historical discharge current change subsequences with the smallest number of sequences is the combination of the first historical discharge current change subsequence set and the second historical discharge current change subsequence set.

[0075] The first calibration capacity corresponding to each first historical discharge current change sequence is obtained based on the correlation relationship, and the first calibration capacities are added together to obtain the total calibration capacity.

[0076] The current loss capacity of the power equipment between the target time and the current time is determined based on the total rated capacity and the first sequence length ratio, wherein the first sequence length ratio is the ratio of the sequence length of the target discharge current change sequence to the sum of the sequence lengths of each first historical discharge current change sequence.

[0077] Furthermore, it is assumed that the first set of historical discharge current change subsequences corresponds to the first historical discharge current change sequence, and the second set of historical discharge current change subsequences corresponds to the second historical discharge current change sequence.

[0078] The calibration capacities corresponding to the first historical discharge current change sequence and the second historical discharge current change sequence are 1200mAh and 1200mAh, respectively. The total calibration capacity when added together is 1200mAh + 1200mAh = 2400mAh.

[0079] At this point, the sum of the sequence lengths of the first historical discharge current change sequence and the second historical discharge current change sequence is 20, and the sequence length of the target discharge current change sequence is 9. Therefore, the current capacity loss of the sodium-ion battery from the target discharge start time to the current time is 2400mAh × (9 / 21) = 1028.57mAh, which is calculated by multiplying the ratio of the target discharge current change sequence length to the sum of the sequence lengths of the first and second historical discharge current change sequences by the total calibrated capacity.

[0080] In one specific embodiment, after determining whether there exists at least one set of historical discharge current change subsequences containing the target subsequence set, if there is no set of at least one set of historical discharge current change subsequences containing the target subsequence set, then a historical discharge current change sequence with the same current change as a target discharge current change subsequence is assigned to a set of historical discharge current change sequences, wherein a certain historical discharge current change subsequence of the certain historical discharge current change sequence has the same current change as a target discharge current change subsequence.

[0081] It should be noted that if none of the target discharge current change subsequences have a matching historical discharge current change subsequence, then the historical discharge current change sequence adjacent to the target discharge current change sequence is directly assigned to the historical discharge current change sequence combination.

[0082] Assume that the target subsequence set contains target discharge current change subsequence a (0.2A, 0.2A), target discharge current change subsequence b (0.3A, 0.3A), target discharge current change subsequence c (0.4A), target discharge current change subsequence d (0.2A), and target discharge current change subsequence e (0.1A, 0.1A, 0.1A).

[0083] The set of historical discharge current change subsequences consists only of the first set of historical discharge current change subsequences and the third set of historical discharge current change subsequences. The first set of historical discharge current change subsequences includes the following historical discharge current change subsequences: a1 (0.2A, 0.2A), b1 (0.3A, 0.3A), c1 (0.4A), d1 (0.2A, 0.2A), e1 (0.1A, 0.1A), and f1 (0.2A, 0.2A).

[0084] The third set of historical discharge current change subsequences includes historical discharge current change subsequences a3 (0.2A, 0.2A), b3 (0.3A, 0.3A), c3 (0.4A, 0.4A), and d3 (0.1, 0.1A, 0.1A).

[0085] Although the combination of the first and third historical discharge current change subsequence sets does not completely cover the target subsequence set, the first and third historical discharge current change subsequence sets are still classified as combinations of historical discharge current change sequences. Specifically, the first and third historical discharge current change subsequence sets correspond to the first and third historical discharge current change sequences, respectively.

[0086] The calibration capacity corresponding to the first and third historical discharge current change sequences is obtained based on the correlation relationship. These calibration capacities are then summed to obtain the total calibration capacity. Based on the total calibration capacity and the ratio of the first sequence length, the current loss capacity of the power equipment between the target time and the current time is determined.

[0087] Step S103: Find at least one target historical calibration capacity that is associated with the at least one target historical discharge current change sequence, and determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule.

[0088] In this step, based on the chronological order, at least one target historical discharge current with the same current value is extracted from at least one target historical discharge current change sequence. Each extraction yields a target historical discharge current change subsequence, and finally, a set of target historical discharge current change subsequences corresponding to at least one target historical discharge current change sequence is obtained.

[0089] The number of subsequences in the set of subsequences of historical discharge current changes for each target is defined as the first subsequence number, and the number of subsequences in the set of subsequences of the target is defined as the second subsequence number.

[0090] Select the first target subsequence number with the smallest difference from the second subsequence number among the first subsequence numbers, and obtain the first target historical discharge current change sequence corresponding to the first target subsequence number;

[0091] The first battery calibration capacity corresponding to the historical discharge current change sequence of the first target is obtained based on the correlation relationship.

[0092] The current loss capacity of the power equipment between the target time and the current time is determined based on the first battery calibrated capacity and the second sequence length ratio, wherein the second sequence length ratio is the ratio between the sequence length of the target discharge current change sequence and the sequence length of the first target historical discharge current change sequence.

[0093] Assuming the target discharge current change sequence length is 15, the first target historical discharge current change sequence length is 20, and the corresponding first battery calibrated capacity is 2000mAh, then: the second sequence length ratio = 15 / 20 = 0.75, and the current capacity loss = 2000mAh × 0.75 = 1500mAh.

[0094] In this embodiment, the accuracy and adaptability of capacity analysis are significantly improved by accurately matching current change patterns. It can effectively identify the capacity decay characteristics under different discharge modes. Based on the matching strategy of dynamic subsequence segmentation and pattern recognition, it can overcome the shortcomings of traditional methods with large errors under variable load conditions as much as possible. Furthermore, through capacity matching rules, it achieves accurate mapping from current change characteristics to capacity loss, providing a more reliable technical basis for the health status assessment of power equipment. While ensuring the accuracy of analysis as much as possible, it reduces the complexity of system implementation and provides a practical technical solution for the intelligent operation and maintenance of various types of power equipment.

[0095] Step S104: Determine the current rated capacity of the power equipment in the current discharge cycle based on the initial rated capacity of the power equipment, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time.

[0096] In this step, the first polarization internal resistance of the power equipment in the first discharge cycle is obtained, wherein the first discharge cycle is the discharge time cycle adjacent to the current discharge cycle; the initial polarization internal resistance after the first cycle of the power equipment is obtained, and the internal resistance ratio between the initial polarization internal resistance and the first polarization internal resistance is calculated; the current rated capacity of the power equipment in the current discharge time cycle is calculated based on the initial rated capacity and the internal resistance ratio.

[0097] Specifically, based on the positive correlation between polarization resistance and capacity decay during battery aging, the rated capacity for the current discharge cycle is estimated by measuring changes in polarization resistance. Polarization resistance increases with battery aging, while the rated capacity decreases accordingly; a definite functional relationship exists between the two.

[0098] Therefore, the polarization resistance of the power device in the first discharge cycle can be read from the battery management system (BMS) or dedicated testing equipment. Alternatively, the accurate first polarization resistance can be obtained by measuring existing methods such as electrochemical impedance spectroscopy (EIS) or DC pulse method.

[0099] Furthermore, the initial polarization internal resistance value of the power equipment after the first cycle is retrieved from the equipment archive. Then, the internal resistance ratio between the initial polarization internal resistance and the first polarization internal resistance is calculated; based on the initial rated capacity and the internal resistance ratio, the current rated capacity of the power equipment in the current discharge time cycle is calculated.

[0100] Step S105: Based on the current rated capacity and the current lost capacity, determine the remaining capacity of the power equipment at the current moment using a preset capacity analysis strategy.

[0101] In this step, the current rated capacity is subtracted from the current lost capacity to obtain the remaining capacity of the power equipment at the current moment.

[0102] In summary, the method of this application first establishes a complete capacity analysis database by establishing the correlation between historical discharge current sequences and rated capacity. Then, it employs a multi-level matching strategy between the target sequence and historical sequences, including three modes: complete matching, combined matching, and subsequence matching, ensuring reliable matching results under varying data completeness conditions. Through accurate identification of current change patterns and dynamic subsequence segmentation technology, it effectively solves the problem of poor adaptability of traditional methods under varying load conditions. Combining the correlation characteristics between polarization resistance changes and capacity decay, it achieves a relatively accurate estimation of the current rated capacity. Finally, it integrates the current rated capacity and lost capacity through a capacity analysis strategy to obtain an accurate assessment of remaining capacity. While maintaining the simplicity of system implementation, it significantly improves the accuracy and reliability of capacity analysis, providing strong technical support for intelligent operation and maintenance and life prediction of power equipment.

[0103] Please refer to Figure 2, which shows a structural block diagram of a power equipment capacity analysis system according to this application.

[0104] As shown in Figure 2, the power equipment capacity analysis system 200 includes an acquisition module 210, a selection module 220, a matching module 230, a determination module 240, and an analysis module 250.

[0105] The acquisition module 210 is configured to acquire the historical rated capacity of the power equipment in each historical discharge cycle, and the historical discharge current change sequence corresponding to each historical discharge cycle, and establish a correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle; the selection module 220 is configured to determine the target discharge current change sequence between the target time and the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence according to the target discharge current change sequence; the matching module 230 is configured to find at least one target historical rated capacity that is correlated with the at least one target historical discharge current change sequence, and determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule; the determination module 240 is configured to determine the current rated capacity in the current discharge cycle based on the initial rated capacity of the power equipment, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time; and the analysis module 250 is configured to determine the remaining capacity of the power equipment in the current time based on the current rated capacity and the current loss capacity using a preset capacity analysis strategy.

[0106] It should be understood that the modules shown in Figure 2 correspond to the steps in the method described with reference to Figure 1. Therefore, the operations, features, and corresponding technical effects described above for the method also apply to the modules in Figure 2, and will not be repeated here.

[0107] In other embodiments, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor performs the power equipment capacity analysis method in any of the above method embodiments.

[0108] In one embodiment, the computer-readable storage medium of the present invention stores computer-executable instructions, which are configured as follows:

[0109] The historical rated capacity of the power equipment in each historical discharge cycle is obtained, as well as the historical discharge current change sequence corresponding to each historical discharge cycle, and the correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle is established.

[0110] Determine the target discharge current change sequence from the target time to the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence;

[0111] Find at least one target historical calibration capacity that is correlated with the at least one target historical discharge current change sequence, and determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule;

[0112] The current rated capacity of the power equipment is determined based on the initial rated capacity of the power equipment in the current discharge cycle, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time;

[0113] Based on the current rated capacity and the current lost capacity, a preset capacity analysis strategy is used to determine the remaining capacity of the power equipment at the current moment.

[0114] Computer-readable storage media may include a stored program area and a stored data area, wherein the stored program area may store an operating system and an application program required for at least one function; the stored data area may store data created based on the use of the power equipment capacity analysis system, etc. Furthermore, the computer-readable storage medium may include high-speed random access memory, and may also include memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the computer-readable storage medium may optionally include memory remotely disposed relative to a processor, which can be connected to the power equipment capacity analysis system via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0115] Figure 3 is a schematic diagram of the electronic device provided in an embodiment of the present invention. As shown in Figure 3, the device includes a processor 310 and a memory 320. The electronic device may also include an input device 330 and an output device 340. The processor 310, memory 320, input device 330, and output device 340 can be connected via a bus or other means; Figure 3 shows an example of connection via a bus. The memory 320 is the aforementioned computer-readable storage medium. The processor 310 executes various functional applications and data processing of the server by running non-volatile software programs, instructions, and modules stored in the memory 320, thereby implementing the power equipment capacity analysis method of the above-described method embodiment. The input device 330 can receive input digital or character information and generate key signal inputs related to user settings and function control of the power equipment capacity analysis system. The output device 340 may include a display screen or other display device.

[0116] The aforementioned electronic device can execute the method provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the method provided in the embodiments of the present invention.

[0117] In one implementation, the above-described electronic device is applied to a power equipment capacity analysis system for a client, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0118] The historical rated capacity of the power equipment in each historical discharge cycle is obtained, as well as the historical discharge current change sequence corresponding to each historical discharge cycle, and the correlation between the historical rated capacity and the historical discharge current change sequence in a unified historical discharge cycle is established.

[0119] Determine the target discharge current change sequence from the target time to the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence;

[0120] Find at least one target historical calibration capacity that is correlated with the at least one target historical discharge current change sequence, and determine the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule;

[0121] The current rated capacity of the power equipment is determined based on the initial rated capacity of the power equipment in the current discharge cycle, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time;

[0122] Based on the current rated capacity and the current lost capacity, a preset capacity analysis strategy is used to determine the remaining capacity of the power equipment at the current moment.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for capacity analysis of power equipment, characterized in that, include: The process involves: acquiring the historical rated capacity of power equipment in each historical discharge cycle, and the historical discharge current change sequence corresponding to each historical discharge cycle; establishing a unified correlation between the historical rated capacity and the historical discharge current change sequence for each historical discharge cycle; determining the target discharge current change sequence between the target time and the current time; and selecting at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence, wherein the target time is the start discharge time with the shortest interval from the current time; selecting at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence includes: sequentially extracting at least one discharge current with the same current value from the target discharge current change sequence according to time order, obtaining a target discharge current change subsequence each time, and classifying each target discharge current change subsequence into a target subsequence set; further extracting each historical discharge current change sequence to obtain at least one set of historical discharge current change subsequences; and determining whether there is at least one target discharge current change subsequence in the at least one set of historical discharge current change subsequences that is the same as the target subsequence set. A set of historical discharge current change subsequences is defined, wherein if the subsequence length and current value of each target historical discharge current change subsequence in a certain target historical discharge current change subsequence set are the same as the subsequence length and current value of each target discharge current change subsequence in the target subsequence set, then the target subsequence set is determined to be the same as the target historical discharge current change subsequence set; if there exists at least one target historical discharge current change subsequence set that is the same as the target subsequence set, then a target historical discharge current change sequence corresponding to the at least one target historical discharge current change subsequence set is selected; at least one target historical calibration capacity that is associated with the at least one target historical discharge current change sequence is found, and the current loss capacity of the power equipment between the target time and the current time is determined using a preset capacity matching rule; the current calibration capacity in the current discharge cycle is determined based on the initial calibration capacity of the power equipment, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time; based on the current calibration capacity and the current loss capacity, the remaining capacity of the power equipment at the current time is determined using a preset capacity analysis strategy.

2. The power equipment capacity analysis method according to claim 1, characterized in that, in, The historical discharge cycle is the time period from the start of discharge to the end of discharge. A certain historical discharge current change sequence contains historical discharge currents sorted by time within a certain historical discharge cycle.

3. The power equipment capacity analysis method according to claim 1, characterized in that, After determining whether there exists at least one target historical discharge current change subsequence set that is identical to the target subsequence set in the at least one set of historical discharge current change subsequences, the method further includes: if there is no at least one target historical discharge current change subsequence set identical to the target subsequence set, then determining whether there exists at least one combination of historical discharge current change subsequence sets that includes the target subsequence set; if there exists at least one combination of historical discharge current change subsequence sets that includes the target subsequence set, then selecting the historical discharge current change subsequence set combination with the smallest number of sequences from the at least one combination of historical discharge current change subsequence sets, and... The historical discharge current change sequence corresponding to each historical discharge current change subsequence set in the combination of the historical discharge current change subsequence sets is defined as the first historical discharge current change sequence; the first calibration capacity corresponding to each first historical discharge current change sequence is obtained according to the correlation relationship, and the first calibration capacity is added together to obtain the total calibration capacity; the current loss capacity of the power equipment between the target time and the current time is determined according to the total calibration capacity and the first sequence length ratio, wherein the first sequence length ratio is the ratio of the sequence length of the target discharge current change sequence to the sum of the sequence lengths of each first historical discharge current change sequence.

4. The power equipment capacity analysis method according to claim 3, characterized in that, After determining whether there exists at least one set of historical discharge current change subsequences containing the target subsequence set, the method further includes: if there is no set of at least one set of historical discharge current change subsequences containing the target subsequence set, then a historical discharge current change sequence that has the same current change as a target discharge current change subsequence is assigned to a set of historical discharge current change sequences, wherein a historical discharge current change subsequence of the historical discharge current change sequence has the same current change as a target discharge current change subsequence.

5. The power equipment capacity analysis method according to claim 1, characterized in that, The step of finding at least one target historical calibration capacity that is associated with the at least one target historical discharge current change sequence, and determining the current loss capacity of the power equipment between the target time and the current time using a preset capacity matching rule, includes: extracting at least one target historical discharge current with the same current value from the at least one target historical discharge current change sequence based on chronological order, extracting one target historical discharge current change subsequence each time, and finally obtaining a set of target historical discharge current change subsequences corresponding to the at least one target historical discharge current change sequence; obtaining the number of subsequences in each target historical discharge current change subsequence set, defined as the first subsequence number, and obtaining the target... The number of subsequences in the target subsequence set is defined as the second subsequence number; among the various first subsequence numbers, the first target subsequence number with the smallest difference from the second subsequence number is selected, and the first target historical discharge current change sequence corresponding to the first target subsequence number is obtained; the first battery calibration capacity corresponding to the first target historical discharge current change sequence is obtained according to the correlation; the current loss capacity of the power equipment between the target time and the current time is determined according to the first battery calibration capacity and the second sequence length ratio, wherein the second sequence length ratio is the ratio between the sequence length of the target discharge current change sequence and the sequence length of the first target historical discharge current change sequence.

6. The power equipment capacity analysis method according to claim 1, characterized in that, The step of determining the current rated capacity in the current discharge cycle based on the initial rated capacity of the power equipment includes: obtaining the first polarization internal resistance of the power equipment in the first discharge cycle, wherein the first discharge cycle is a discharge time cycle adjacent to the current discharge cycle; obtaining the initial polarization internal resistance after the first cycle of the power equipment, and calculating the internal resistance ratio between the initial polarization internal resistance and the first polarization internal resistance; and calculating the current rated capacity of the power equipment in the current discharge time cycle based on the initial rated capacity and the internal resistance ratio.

7. A power equipment capacity analysis system, characterized in that, include: The acquisition module is configured to acquire the historical rated capacity of power equipment in each historical discharge cycle, and the historical discharge current change sequence corresponding to each historical discharge cycle, and establish a unified correlation between the historical rated capacity and the historical discharge current change sequence for each historical discharge cycle; the selection module is configured to determine the target discharge current change sequence between the target time and the current time, and select at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence, wherein the target time is the start discharge time with the shortest interval from the current time; the step of selecting at least one target historical discharge current change sequence from each historical discharge current change sequence based on the target discharge current change sequence includes: extracting at least one discharge current with the same current value in the target discharge current change sequence according to the time sequence, extracting a target discharge current change subsequence each time, and dividing each target discharge current change subsequence into a target subsequence set; extracting each historical discharge current change sequence again to obtain at least one set of historical discharge current change subsequences; and determining whether there is at least one target historical discharge current change sequence in the at least one set of historical discharge current change subsequences that is the same as the target subsequence set. A set of subsequences of electrical current changes, wherein, when the subsequence length and current value of each subsequence of a target historical discharge current change in a certain target subsequence set are the same as the subsequence length and current value of each subsequence of a target discharge current change in the target subsequence set, then the target subsequence set is determined to be the same as the target historical discharge current change subsequence set; if there exists at least one target historical discharge current change subsequence set that is the same as the target subsequence set, then the target historical discharge current change sequence corresponding to the at least one target historical discharge current change subsequence set is selected; a matching module, configured. To locate at least one target historical calibration capacity that is correlated with the at least one target historical discharge current change sequence, a preset capacity matching rule is used to determine the current loss capacity of the power equipment between the target time and the current time; the determination module is configured to determine the current calibration capacity in the current discharge cycle based on the initial calibration capacity of the power equipment, wherein the current discharge cycle is a discharge cycle that includes the target time and the current time; the analysis module is configured to determine the remaining capacity of the power equipment at the current time based on the current calibration capacity and the current loss capacity, using a preset capacity analysis strategy.

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