High-capacity battery pack state monitoring and equalization control method, system and device

Abstract

The invention relates to the technical field of electric energy storage, in particular to a high-capacity battery pack state monitoring and equalization control method, system and device, and the method comprises the steps: obtaining the monitoring data of a plurality of single batteries in a high-capacity battery pack; determining a load state corresponding to each single battery based on the monitoring data of the plurality of single batteries; analyzing the influence of the load state corresponding to each single battery on the balancing efficiency, determining the adaptation degree of balancing of each single battery at the current moment, and determining the balancing priority corresponding to each single battery according to the adaptation degree; and performing equalization control on part of the single batteries in the high-capacity battery pack based on the equalization priorities corresponding to the single batteries. When the scheme is used in the electric energy storage process, the interference of load change on voltage judgment can be effectively reduced, the single battery which most needs to be balanced can be processed preferentially, the efficiency of balance control is improved, and the service life of the battery pack is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy storage, and in particular to a method, system and device for monitoring and balancing a large-capacity battery pack. Background Art

[0002] A large-capacity battery pack refers to a battery system that can store a large amount of electrical energy. It is composed of multiple single cells connected in series and parallel. It is used to store and provide a large amount of energy. It is often used in power tools during construction. Generally speaking, more than 10kWh (kilowatt-hours) can be considered "large capacity". Since large-capacity battery packs are usually composed of multiple single cells, there may be differences between the single cells. The lack of effective balancing control will lead to overall performance degradation, energy loss and shortened battery life. In order to ensure the efficient and safe operation of the battery pack, the voltage and other data of the battery pack are generally monitored in real time to evaluate the status of each single cell. By adjusting the energy distribution of each single cell, the imbalance caused by the voltage difference between the single cells is eliminated, and the excessive use or aging of local batteries is avoided, thereby achieving balancing control to ensure the optimization of battery pack performance, extend service life and ensure safety.

[0003] In the prior art, in the process of balancing and controlling a large-capacity battery pack through voltage, the load change in the battery pack has a particularly significant impact on the voltage value, which directly causes the voltage to be unable to truly reflect the battery's state of charge (SOC). For example, when the load changes rapidly, the battery voltage will fluctuate violently due to the internal resistance effect and polarization phenomenon, making the relationship between the voltage and the actual SOC unstable. Since the balancing system usually relies on the voltage value as a basis for judgment, when the voltage fluctuates for a short time, the system may misjudge the actual state of the battery, thereby triggering unnecessary balancing actions and failing to effectively improve the unbalanced state of the battery pack.

[0004] Therefore, how to effectively balance and control large-capacity battery packs is a problem that needs to be solved urgently. Summary of the invention

[0005] In order to solve the technical problem of how to effectively balance control a large-capacity battery pack, the purpose of the present invention is to provide a large-capacity battery pack state monitoring and balance control method, system and device, the technical solution adopted is as follows:

[0006] An embodiment of the present invention provides a large-capacity battery pack state monitoring and balancing control method, the method comprising:

[0007] Obtain monitoring data of multiple single cells in a large-capacity battery pack;

[0008] Determining a load state corresponding to each of the single cells based on the monitoring data of the multiple single cells;

[0009] Analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells for balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability;

[0010] Based on the balancing priority corresponding to each of the single cells, balancing control is performed on some of the single cells in the large-capacity battery pack.

[0011] In one embodiment of the present invention, after acquiring the monitoring data of a plurality of single cells in the large-capacity battery pack, the method further includes:

[0012] removing random noise from the monitoring data to obtain first monitoring data;

[0013] Performing filtering optimization on the first monitoring data to obtain second monitoring data;

[0014] The second monitoring data is subjected to temperature compensation and aging effect correction to obtain preprocessed monitoring data, and the preprocessed monitoring data is used to determine a load state corresponding to the large-capacity battery pack.

[0015] In one embodiment of the present invention, the monitoring data includes current data, and determining the load state corresponding to each of the single cells based on the monitoring data of the plurality of single cells includes:

[0016] For each of the single cells, extract a current segment from the current data, and determine a current mean value corresponding to the current segment;

[0017] According to a preset neighborhood radius and a minimum number of samples, the current mean value is clustered to obtain a clustering result, and the load state corresponding to each of the single cells is determined according to the clustering result.

[0018] In one embodiment of the present invention, the monitoring data includes voltage data, and the analyzing the influence of the load state corresponding to each of the single cells on the balancing efficiency, determining the adaptability of each of the single cells for balancing at the current moment, and determining the balancing priority corresponding to each of the single cells according to the adaptability, includes:

[0019] Determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within a preset neighborhood range at the current moment;

[0020] Analyzing the influence of the load state on the equalization efficiency of the single cell, and determining the equalization inadaptability corresponding to the single cell;

[0021] The balancing priority corresponding to the single battery is determined according to the necessary degree of energy transfer and the balancing inadaptability.

[0022] In one embodiment of the present invention, determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within a preset neighborhood at the current moment includes:

[0023] Taking the average value of the voltage data within a preset neighborhood at the current moment as the energy transfer demand corresponding to the single battery;

[0024] Taking the variance of the voltage data within a preset neighborhood at the current moment as the voltage credibility corresponding to the single battery;

[0025] Determining the necessity of energy transfer corresponding to the single battery in combination with the energy transfer requirement and the voltage credibility;

[0026] The degree of necessity of energy transfer corresponding to the single cell is determined according to a difference between the necessity of energy transfer corresponding to the single cell and a maximum value of the necessity of energy transfer corresponding to all the single cells.

[0027] In one embodiment of the present invention, analyzing the influence of the load state on the balancing efficiency of the single cell and determining the balancing inadaptability corresponding to the single cell includes:

[0028] Analyzing the reduction of the voltage data through the correlation between the current data and the voltage data to determine the abnormal reduction degree corresponding to the voltage data;

[0029] Determining the equalization efficiency corresponding to the single cell according to the voltage change of the single cell during the historical equalization process;

[0030] Analyzing the correlation between the abnormal reduction degree under the load state and the change of the balancing efficiency, and determining the effect of the load state on the balancing efficiency according to the change correlation degree;

[0031] The balancing inadaptability corresponding to the single cell is determined according to the effect of the load state of the single cell at the current moment on the balancing efficiency and the effect of the minimum load state on the balancing efficiency.

[0032] In one embodiment of the present invention, determining the balancing priority corresponding to the single battery according to the necessary degree of energy transfer and the balancing inadaptability includes:

[0033] Determining the balancing adaptability of the single battery at the current moment according to the balancing unadaptability;

[0034] The balancing priority corresponding to the single cell is determined based on the necessary degree of energy transfer of the single cell at the current moment and the balancing adaptability.

[0035] In one embodiment of the present invention, the balancing control of some single cells in the large-capacity battery pack based on the balancing priority corresponding to each single cell includes:

[0036] When the voltage difference between the plurality of single cells is greater than a preset voltage difference threshold, determining an energy transfer path according to the balancing priority corresponding to each of the single cells;

[0037] Through the energy transfer path, energy is transferred from a single cell with a high voltage to a single cell with the highest balancing priority by using an inductor, so as to achieve balancing control.

[0038] An embodiment of the present invention also provides a large-capacity battery pack state monitoring and balancing control system, the system including a computer-readable storage medium, the computer-readable storage medium storing a plurality of instructions, the instructions being suitable for a processor to load to execute the steps in the large-capacity battery pack state monitoring and balancing control method as described above.

[0039] The embodiment of the present invention further provides a large-capacity battery pack state monitoring and balancing control device, the device comprising:

[0040] A data acquisition module, used to acquire monitoring data of multiple single cells in a large-capacity battery pack;

[0041] A load state determination module, used for determining the load state corresponding to each of the single cells based on the monitoring data of the multiple single cells;

[0042] A balancing priority determination module, used to analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells to balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability;

[0043] The balancing control module is used to perform balancing control on some single cells in the large-capacity battery pack based on the balancing priority corresponding to each single cell.

[0044] The present invention has the following beneficial effects:

[0045] First, the monitoring data of multiple single cells in a large-capacity battery pack is obtained; then, based on the monitoring data of the multiple single cells, the load state corresponding to each of the single cells is determined; then, the influence of the load state corresponding to each of the single cells on the balancing efficiency is analyzed, the adaptability of each of the single cells for balancing at the current moment is determined, and the balancing priority corresponding to each of the single cells is determined according to the adaptability; finally, based on the balancing priority corresponding to each of the single cells, balancing control is performed on some of the single cells in the large-capacity battery pack. In the present invention, the load state of each single cell is determined based on the monitoring data of multiple single cells in a large-capacity battery pack, which not only takes into account the voltage value but also combines the load characteristics, so as to more comprehensively evaluate the actual working state of the single cell, effectively reduce the interference of load changes on voltage judgment, and improve the accuracy of state evaluation; by analyzing the influence of the load state on the balancing efficiency, the adaptability of each single cell for balancing at the current moment is determined, avoiding the limitation of relying solely on the voltage value for balancing judgment, ensuring that the balancing action is more reasonable and efficient, avoiding misjudgment caused by the load state, and thus improving the overall balancing efficiency; according to the balancing adaptability of each single cell, its corresponding balancing priority is determined, and the single cell that most needs balancing can be processed preferentially, thereby improving the efficiency of balancing control, reducing unnecessary balancing operations, and extending the service life of the battery pack; based on the balancing priority of each single cell, balancing control is performed on some single cells, which can concentrate resources to deal with key issues, improve the overall effect of balancing control, ensure that limited balancing resources are used preferentially for the single cells that need it most, and avoid resource dispersion. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A schematic diagram of an implementation environment of a large-capacity battery pack state monitoring and balancing control method provided by an embodiment of the present invention;

[0048] Figure 2 A schematic flow chart of a large-capacity battery pack state monitoring and balancing control method provided by an embodiment of the present invention;

[0049] Figure 3 A schematic diagram of a voltage drop abnormality provided by an embodiment of the present invention;

[0050] Figure 4A schematic diagram of the structure of a large-capacity battery pack state monitoring and balancing control device provided by an embodiment of the present invention;

[0051] Figure 5 A schematic diagram of the structure of a computer system suitable for electronic equipment provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a large-capacity battery pack state monitoring and balancing control method, system and device proposed by the present invention, its specific implementation, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0053] It should be noted that the terms "first", "second", etc. in the specification of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0054] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0055] The specific scheme of a large-capacity battery pack state monitoring and balancing control method, system and device provided by the present invention is described in detail below with reference to the accompanying drawings.

[0056] See also Figure 1 , Figure 1 The following is a schematic diagram of an implementation environment of a large-capacity battery pack state monitoring and balancing control method provided by an embodiment of the present invention. Figure 1As shown, the implementation environment includes a large-capacity battery pack 101, a balancing control terminal 102, and a battery management terminal 103, wherein the large-capacity battery pack 101 includes a plurality of single cells, and a battery management system is installed in the battery management terminal 103. The balancing control terminal 102 includes but is not limited to a laptop computer, a tablet computer, a handheld computer, a PAD, a desktop computer, etc. with local computing capabilities; the balancing control terminal 102 can communicate with the large-capacity battery pack 101 and the battery management terminal 103 through a network, and the network can include but is not limited to: a wired network, a wireless network, wherein the wired network includes: a local area network, a metropolitan area network, and a wide area network, and the wireless network includes: Bluetooth, WIFI, and other networks that implement wireless communication. The above-mentioned balancing control terminal 102 can include but is not limited to a human-computer interaction screen, a processor, and a memory. The above-mentioned human-computer interaction screen can be but is not limited to being used to display the balancing control result. The above-mentioned processor can be but is not limited to being used to respond to human-computer interaction operations, perform corresponding operations, or generate corresponding instructions.

[0057] As an optional manner, the above-mentioned balancing control terminal 102 may also be a server, which may be a single server, a server cluster composed of multiple servers, or a cloud server. The above is only an example, and this embodiment does not make any limitation to this.

[0058] As an optional method, the battery management terminal 103 obtains monitoring data of multiple single cells from the large-capacity battery pack 101, and then transmits the monitoring data to the balancing control terminal 102 for balancing control.

[0059] As an optional method, the following steps of the large-capacity battery pack state monitoring and balancing control method may be performed on the balancing control terminal 102:

[0060] Obtain monitoring data of multiple single cells in a large-capacity battery pack;

[0061] Determining a load state corresponding to each of the single cells based on the monitoring data of the multiple single cells;

[0062] Analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells for balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability;

[0063] Based on the balancing priority corresponding to each of the single cells, balancing control is performed on some of the single cells in the large-capacity battery pack.

[0064] The above method determines the load state of each single cell based on the monitoring data of multiple single cells in a large-capacity battery pack, which not only takes into account the voltage value, but also combines the load characteristics, and can more comprehensively evaluate the actual working state of the single cell, effectively reduce the interference of load changes on voltage judgment, and improve the accuracy of state evaluation; by analyzing the impact of the load state on the balancing efficiency, the adaptability of each single cell for balancing at the current moment is determined, avoiding the limitation of relying solely on the voltage value for balancing judgment, ensuring that the balancing action is more reasonable and efficient, avoiding misjudgment caused by the load state, and thus improving the overall balancing efficiency; according to the balancing adaptability of each single cell, its corresponding balancing priority is determined, and the single cell that most needs balancing can be processed first, thereby improving the efficiency of balancing control, reducing unnecessary balancing operations, and extending the service life of the battery pack; based on the balancing priority of each single cell, balancing control is performed on some single cells, which can concentrate resources to deal with key issues, improve the overall effect of balancing control, ensure that limited balancing resources are used first for the single cells that need it most, and avoid resource dispersion.

[0065] As an optional example, this embodiment does not limit the execution subject of the above-mentioned large-capacity battery pack status monitoring and balancing control method. The above-mentioned large-capacity battery pack status monitoring and balancing control method can be executed on the balancing control terminal 102. For example, when the balancing control terminal 102 is a desktop computer, some or all steps of the above-mentioned large-capacity battery pack status monitoring and balancing control method can be executed on the desktop computer.

[0066] The above section introduces the contents of an exemplary implementation environment for applying the technical solution of the present invention. Next, the large-capacity battery pack state monitoring and balancing control method of the present invention will be introduced.

[0067] In order to solve the problem of how to effectively balance and control large-capacity battery packs in the prior art, the embodiments of the present invention respectively propose a large-capacity battery pack state monitoring and balancing control method, a large-capacity battery pack state monitoring and balancing control device, an electronic device, and a large-capacity battery pack state monitoring and balancing control system. These embodiments will be described in detail below.

[0068] See also Figure 2 , Figure 2 A flow chart of a large-capacity battery pack state monitoring and balancing control method provided by an embodiment of the present invention, which can be applied to Figure 1 It should be understood that the method can also be applied to other exemplary implementation environments and specifically executed by devices in other implementation environments, and this embodiment does not limit the implementation environment to which the method is applicable.

[0069] like Figure 2As shown, in an exemplary embodiment, the large-capacity battery pack state monitoring and balancing control method includes at least steps S210 to S240, which are described in detail as follows:

[0070] In step S210, monitoring data of a plurality of single cells in a large-capacity battery pack is obtained.

[0071] Among them, a large-capacity battery pack is composed of multiple single cells, each of which is an independent energy storage unit with its own voltage, current, temperature and other characteristics. The state of the single cell directly affects the performance of the entire battery pack. By monitoring and controlling the state of the single cell, the overall optimization of the battery pack can be achieved.

[0072] Among them, monitoring data refers to various real-time data collected from single cells, including but not limited to voltage, current, temperature, internal resistance, etc. Monitoring data is the basis for evaluating the status of single cells. By analyzing these data, we can understand the working condition and load characteristics of the battery.

[0073] In step S220, based on the monitoring data of the plurality of single cells, a load state corresponding to each of the single cells is determined.

[0074] The load state describes the workload of a single cell at the current moment, usually reflected by the current value and its changing trend. The load state affects the voltage performance and balancing efficiency of the battery. A high load may cause voltage fluctuations, while a low load may leave the battery idle.

[0075] Among them, based on the monitoring data of the plurality of single cells, when determining the load state corresponding to each single cell, the current data of the single cell can be obtained, and the current data can be processed by sliding window (such as taking the average of 11 data points with a left and right radius of 5), and then the clustering algorithm is used to classify the current mean, and different current modes are mapped to different load states. By quantifying the load state, the actual working conditions of the single cell can be understood more accurately.

[0076] In step S230, the influence of the load state corresponding to each of the single cells on the balancing efficiency is analyzed to determine the adaptability of each of the single cells for balancing at the current moment, and the balancing priority corresponding to each of the single cells is determined according to the adaptability.

[0077] Among them, balancing efficiency refers to the effectiveness of energy transfer of single cells during the balancing process. It is affected by factors such as load state, internal resistance and polarization effect. The balancing efficiency determines whether the balancing operation can effectively improve the consistency of the battery pack.

[0078] Among them, the adaptability of balancing is to measure whether the single cell battery is suitable for balancing at the current moment. It comprehensively considers the load status, voltage fluctuation and historical balancing performance, and can be used to determine which single cells need to be balanced first to avoid unnecessary balancing actions.

[0079] Among them, when analyzing the influence of the load state corresponding to each of the single cells on the balancing efficiency and determining the adaptability of each of the single cells for balancing at the current moment, the influence of the load state on the voltage value and the balancing efficiency can be analyzed first, and then the necessity of energy transfer of the single cell can be evaluated in combination with the change trend of the voltage data (such as the mean and variance) and the voltage abnormality under the load state. Finally, according to the historical performance of the necessity of energy transfer and the balancing efficiency, the balancing adaptability of the single cell is calculated.

[0080] Among them, the balancing priority refers to assigning a priority value to each single cell according to its balancing adaptability, which is used to determine the allocation order of balancing resources. By sorting by priority, resources are concentrated on processing the single cells that need balancing the most, thus improving the overall balancing efficiency.

[0081] When determining the balancing priority corresponding to each of the single cells according to the adaptability, the balancing adaptability of the single cell may be compared with the maximum adaptability of all single cells; and a priority value is assigned to each single cell according to the comparison result.

[0082] In step S240, based on the balancing priority corresponding to each of the single cells, balancing control is performed on some of the single cells in the large-capacity battery pack.

[0083] As can be seen from the above steps S210 to S240, the solution proposed in this embodiment determines the load state of each single cell based on the monitoring data of multiple single cells in the large-capacity battery pack, not only considering the voltage value, but also combining the load characteristics, which can more comprehensively evaluate the actual working state of the single cell, effectively reduce the interference of load changes on voltage judgment, and improve the accuracy of state evaluation; by analyzing the impact of the load state on the balancing efficiency, the adaptability of each single cell to balancing at the current moment is determined, avoiding the limitation of relying solely on the voltage value for balancing judgment, ensuring that the balancing action is more reasonable and efficient, avoiding misjudgment caused by the load state, and thus improving the overall balancing efficiency; according to the balancing adaptability of each single cell, the corresponding balancing priority is determined, and the single cell that needs balancing the most can be processed first, thereby improving the efficiency of balancing control, reducing unnecessary balancing operations, and extending the service life of the battery pack; based on the balancing priority of each single cell, balancing control is performed on some single cells, which can concentrate resources to deal with key issues, improve the overall effect of balancing control, ensure that limited balancing resources are used first for the single cells that need it the most, and avoid resource dispersion.

[0084] In one embodiment of the present invention, after acquiring the monitoring data of a plurality of single cells in the large-capacity battery pack, the method further includes:

[0085] removing random noise from the monitoring data to obtain first monitoring data;

[0086] Performing filtering optimization on the first monitoring data to obtain second monitoring data;

[0087] The second monitoring data is subjected to temperature compensation and aging effect correction to obtain preprocessed monitoring data, and the preprocessed monitoring data is used to determine a load state corresponding to the large-capacity battery pack.

[0088] Among them, random noise refers to irregular fluctuations in monitoring data caused by external interference or measurement errors, which usually appear as high-frequency, low-amplitude signals. Random noise will interfere with the accurate judgment of the status of single cells and needs to be removed through denoising processing.

[0089] Among them, when removing random noise in the monitoring data, a sliding average filter or a median filter can be used to perform preliminary smoothing processing on the original monitoring data, detect and eliminate outliers that exceed a reasonable range, reduce the impact of random noise on subsequent analysis, and improve data quality.

[0090] Among them, filtering optimization refers to further smoothing and optimizing the data through mathematical algorithms to retain useful signals and suppress noise. Filtering optimization can better extract key features from monitoring data and provide a more reliable basis for subsequent analysis.

[0091] When filtering and optimizing the first monitoring data, a low-pass filter or a Kalman filter may be applied to process the first monitoring data after removing random noise; and appropriate filtering parameters (such as cutoff frequency or model parameters) may be selected according to data characteristics.

[0092] Temperature compensation refers to the correction of monitoring data based on the impact of temperature on battery performance to make it closer to the true value. Temperature changes will affect parameters such as battery voltage and internal resistance. Temperature compensation can eliminate this impact and improve the accuracy of data analysis.

[0093] Among them, aging effect correction refers to adjusting the monitoring data to take into account the performance degradation of the battery during long-term use. The aging effect will cause the battery capacity to decrease and the internal resistance to increase. After correction, the actual state of the battery can be evaluated more accurately.

[0094] When the second monitoring data is subjected to temperature compensation and aging effect correction, the temperature compensation coefficient and aging correction factor can be calculated according to the current ambient temperature and the battery history usage data; these correction factors are applied to the second monitoring data to obtain the preprocessed monitoring data. The influence of temperature and aging effects on the battery status is comprehensively considered to ensure the accuracy and consistency of the data.

[0095] For example, assume that there is a large-capacity battery pack consisting of three single cells, and collect voltage, current and temperature data of each single cell.

[0096] The voltage, current and temperature can be, for example, (unit: V / A / °C): Cell 1: 4.15V / 5A / 25°C; Cell 2: 4.08V / 8A / 26°C; Cell 3: 3.92V / 10A / 27°C. The voltage data is smoothed using a sliding average filter to obtain: Cell 1: 4.14V; Cell 2: 4.07V; Cell 3: 3.91V, eliminating abnormal values ​​(such as fluctuations exceeding ±0.1V). The denoised data is further optimized using a low-pass filter to obtain: Cell 1: 4.13V; Cell 2: 4.06V; Cell 3: 3.90V. According to the relationship between temperature and voltage, the temperature compensation coefficient is calculated (for example, the voltage decreases by 0.01V for every 1°C increase), and the results are: single cell 1: 4.13-(25-20)×0.01=4.08V; single cell 2: 4.06-(26-20)×0.01=4.00V; single cell 3: 3.90-(27-20)×0.01=3.83V. According to the historical usage data of the battery, the aging correction factor is calculated (for example, the voltage decreases by 0.02V for every year of use), and the results are: single cell 1: 4.08-0.02×2=4.04V; single cell 2: 4.00-0.02×2=3.96V; single cell 3: 3.83-0.02×2=3.79V. Finally, the pre-processed monitoring data obtained are: single cell 1: 4.04V; single cell 2: 3.96V; single cell 3: 3.79V.

[0097] In this embodiment, the quality of monitoring data is significantly improved through denoising, filtering optimization, temperature compensation and aging effect correction, reducing the impact of external interference and internal factors on the data. Comprehensively considering the impact of temperature and aging effects on battery status, the load status judgment is more accurate, providing a reliable basis for subsequent balancing control. Data preprocessing effectively reduces the impact of random noise and system errors, avoids misjudgment caused by data quality problems, and improves the reliability of the system.

[0098] In one embodiment of the present invention, the monitoring data includes current data, and determining the load state corresponding to each of the single cells based on the monitoring data of the plurality of single cells includes:

[0099] For each of the single cells, extract a current segment from the current data, and determine a current mean value corresponding to the current segment;

[0100] According to a preset neighborhood radius and a minimum number of samples, the current mean value is clustered to obtain a clustering result, and the load state corresponding to each of the single cells is determined according to the clustering result.

[0101] Among them, each single cell in the battery pack has different charging and discharging performance due to internal performance differences. The abnormal voltage performance of the single cell under high load is caused by the internal performance of the battery and may recur during multiple uses. It is caused by the load state. Therefore, the load state of the single cell can be represented by the performance of the current at each moment. The impact of the load state on the battery voltage can be further obtained by clustering analysis.

[0102] The current segment refers to a sequence of current values ​​within a continuous period of time extracted from the current data of a single battery. By analyzing the current segment, the load characteristics of the single battery over a period of time can be captured.

[0103] When extracting the current segment from the current data, the size of the sliding window can be determined first (such as a left and right radius of 5 and a total length of 11 data points), and then the current segment centered at the moment can be extracted for the current data at each moment. The original current data is divided into multiple small segments for subsequent calculation and analysis.

[0104] The neighborhood radius refers to the distance threshold used in clustering algorithms to define whether two samples are considered to be the same cluster.

[0105] The minimum number of samples refers to the number of samples that must be included in a cluster in the clustering algorithm.

[0106] Among them, clustering processing refers to dividing similar data points into different groups (clusters) through mathematical algorithms, so that the data points in the same cluster are as similar as possible, and the data points between different clusters are as different as possible, and the current mean can be divided into different load state categories.

[0107] When clustering the current means according to the preset neighborhood radius and the minimum number of samples, the current mean of each current segment can be calculated first; and then a clustering algorithm is used to classify the current means based on the preset neighborhood radius and the minimum number of samples.

[0108] When determining the load state corresponding to each single cell according to the clustering result, each cluster in the clustering result can be first mapped to a load state (such as high load, medium load, low load); then, the corresponding load state is determined according to the cluster to which the current mean of the single cell belongs.

[0109] For example, suppose there is a large-capacity battery pack consisting of 3 cells, and the current data (unit: A) of each cell is collected: Cell 1: [5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]; Cell 2: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]; Cell 3: [20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40]. Use a sliding window (with a radius of 5 on the left and right, a total of 11 data points) to extract the current segment and calculate the mean, and you can get: Cell 1:

[0110] (5+6+7+8+9+10+11+12+13+14+15) / 11=10A; Cell 2: (1+2+3+4+5+6+7+8+9+10+11) / 11=6A; Cell 3: (20+22+24+26+28+30+32+34+36+38+40) / 11=30A. The preset neighborhood radius (Eps) is 5, and the minimum number of samples (MinPts) is 2. The clustering algorithm is used to cluster the current mean, and the results are: Cell 1: 10A, which is cluster 1 (medium load); Cell 2: 6A, which is cluster 2 (low load); Cell 3: 30A, which is cluster 3 (high load). According to the clustering results, the clusters are mapped to load states, and the results are: Cluster 1: medium load; Cluster 2: low load; Cluster 3: high load.

[0111] In this embodiment, the load state of the single battery is divided into discrete categories through clustering of the current mean, which is convenient for subsequent analysis and control. Based on the sliding window, the current segment is extracted and the mean is calculated, which can effectively smooth the data fluctuation, reduce noise interference, and improve the accuracy of load state judgment. The parameters of the clustering algorithm (neighborhood radius and minimum number of samples) can be adjusted according to actual needs and are suitable for load state identification under various complex working conditions.

[0112] In one embodiment of the present invention, the monitoring data includes voltage data, and the analyzing the influence of the load state corresponding to each of the single cells on the balancing efficiency, determining the adaptability of each of the single cells for balancing at the current moment, and determining the balancing priority corresponding to each of the single cells according to the adaptability, includes:

[0113] Determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within a preset neighborhood range at the current moment;

[0114] Analyzing the influence of the load state on the equalization efficiency of the single cell, and determining the equalization inadaptability corresponding to the single cell;

[0115] The balancing priority corresponding to the single battery is determined according to the necessary degree of energy transfer and the balancing inadaptability.

[0116] Among them, during the operation of a large-capacity battery pack, the load change in the battery pack has a particularly significant impact on the voltage value, which directly causes the voltage to be unable to truly reflect the battery's state of charge. When the battery pack is in a high-load state, the battery's voltage will fluctuate violently due to the internal resistance effect and polarization phenomenon. The optimal energy transfer target obtained based only on voltage information may have errors, and the actual state of the battery may be misjudged, thereby triggering unnecessary balancing actions. Frequent ineffective adjustments will significantly increase energy loss and reduce the overall efficiency of the system. Therefore, it is necessary to analyze the impact of the load state corresponding to each of the single cells on the balancing efficiency in order to achieve more accurate and effective balancing operations.

[0117] The preset neighborhood range at the current moment refers to a time window centered at the current moment, which is used to analyze the change trend of voltage data within the range. By examining the change of voltage data within the neighborhood range, the energy state and load characteristics of the single cell can be more comprehensively evaluated.

[0118] Among them, the degree of necessity of energy transfer refers to an indicator to measure whether the single cell battery needs to transfer energy at the current moment. It is usually determined by the changing trend of voltage data and is used to judge the energy demand of the single cell battery and provide a basis for determining the balancing priority.

[0119] Among them, the balancing inadaptability refers to the difficulty or inappropriateness of the single battery in the current load state to perform the balancing operation, which is affected by factors such as load state, internal resistance effect and polarization phenomenon. By analyzing the balancing inadaptability, it is possible to avoid balancing operations under unsuitable conditions and improve the balancing efficiency.

[0120] In this embodiment, by comprehensively considering the necessary degree of energy transfer and the unsuitability of balancing, it is possible to more accurately evaluate whether a single cell is suitable for balancing operation and avoid unnecessary balancing actions. Based on the voltage data and load status at the current moment, the balancing priority is dynamically adjusted to ensure that the balancing control strategy can adapt to different working conditions.

[0121] In one embodiment of the present invention, determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within a preset neighborhood at the current moment includes:

[0122] Taking the average value of the voltage data within a preset neighborhood at the current moment as the energy transfer demand corresponding to the single battery;

[0123] Taking the variance of the voltage data within a preset neighborhood at the current moment as the voltage credibility corresponding to the single battery;

[0124] Determining the necessity of energy transfer corresponding to the single battery in combination with the energy transfer requirement and the voltage credibility;

[0125] The degree of necessity of energy transfer corresponding to the single cell is determined according to a difference between the necessity of energy transfer corresponding to the single cell and a maximum value of the necessity of energy transfer corresponding to all the single cells.

[0126] Among them, the battery will inevitably cause performance differences during the manufacturing process and the use process. The large-capacity battery pack will cause a reduction in service life due to the difference in the charging and discharging characteristics of the single cells. With the accumulation of use, the difference between the batteries becomes more and more obvious. The life of the battery pack depends on the single cell with the worst performance. Therefore, active balancing control is required to improve the life of the battery pack. Taking the voltage of the single cell as the criterion for balancing, during use, battery balancing needs to achieve a balance in the energy stored between the single cells, and the batteries with the largest voltage difference need to transfer energy first.

[0127] The energy transfer demand refers to the energy demand of the single cell at the current moment, which is usually reflected by the mean of the voltage data. By calculating the mean of the voltage data within a preset neighborhood, the energy state of the single cell is evaluated to determine whether it needs energy transfer.

[0128] Among them, voltage credibility refers to the degree of fluctuation of voltage data within a preset neighborhood, which is usually represented by the variance of voltage data. The smaller the variance, the more stable the voltage data and the higher the credibility; conversely, the larger the variance, the greater the fluctuation of voltage data and the lower the credibility.

[0129] Among them, the necessity of energy transfer refers to an indicator that comprehensively considers the energy transfer demand and voltage credibility to evaluate whether the single cell needs energy transfer. Combined with the voltage mean and variance, it more comprehensively reflects the energy state of the single cell and provides a basis for subsequent balancing control.

[0130] Among them, the difference between the necessity of energy transfer corresponding to a single cell and the maximum necessity of energy transfer corresponding to all single cells refers to quantifying the energy transfer priority of the single cell at the current moment by comparing the difference between the necessity of energy transfer of the single cell and the maximum necessity of energy transfer in the entire battery pack, which is used to determine the degree of necessity of energy transfer of the single cell, thereby realizing dynamic adjustment of the balancing strategy.

[0131] For example, due to the performance differences of each single cell in the battery pack, there are differences in the energy distribution in the battery during use. In order to improve the system efficiency and extend the service life of the battery pack, it is necessary to balance the energy transfer. By monitoring the voltage data of the single cells in real time, the battery voltage will inevitably fluctuate during use. Therefore, based on the performance of the voltage data in the neighborhood range, it is determined whether battery balancing control is needed.

[0132] Exemplarily, the necessity of energy transfer may be expressed as:

[0133]

[0134] Among them, D i Indicates the necessity of energy transfer corresponding to the i-th single cell; represents the energy transfer demand corresponding to the ith single cell, that is, the average value of the voltage data within the preset neighborhood range (the first 5 data points of the current voltage) at the current moment. The larger the value, the more energy needs to be transferred; exp is an exponential function; V i It indicates the voltage credibility corresponding to the ith single cell, that is, the variance of the voltage data within the preset neighborhood at the current moment, which represents the referenceability of the current voltage data. The smaller the value, the more credible the voltage of the single cell at the current moment is, which can prevent misjudgment caused by voltage fluctuations.

[0135] in, The larger it is, the more energy transfer the single cell needs.

[0136] Exemplarily, during the battery pack balancing process, the battery with the highest voltage acts as an energy provider, and the battery with the lowest voltage acts as an energy receiver. Single cells with larger voltage differences should be adjusted first. Therefore, single cells with larger voltage differences are two single cells with larger differences in the necessity of energy transfer. Based on the necessity of energy transfer of all single cells in the large-capacity battery pack, the necessity degree of energy transfer of the single cells is obtained.

[0137] Exemplarily, the necessary degree of energy transfer may be expressed as:

[0138]

[0139] Among them, A i Indicates the necessary degree of energy transfer corresponding to the i-th single cell; D i represents the necessity of energy transfer corresponding to the i-th single cell; maxD represents the maximum value of the necessity of energy transfer corresponding to all single cells; D n Indicates the necessity of energy transfer corresponding to the nth single cell; |D i-maxD| represents the difference between the necessity of energy transfer corresponding to the i-th single cell and the maximum necessity of energy transfer corresponding to all single cells, which can represent the necessity of the single cell as an energy receiver.

[0140] in, The mean of the difference between the necessity of energy transfer corresponding to all single cells in the battery pack and the maximum necessity of energy transfer corresponding to all single cells is used to measure the necessity of balancing control at the current moment, where N is greater than 1.

[0141] in, The larger it is, the more necessary it is to transfer energy to the i-th single cell.

[0142] In this embodiment, by introducing voltage credibility as a supplementary indicator, the energy state of the single cell can be evaluated more accurately to avoid misjudgment caused by voltage fluctuations. Based on the necessity of energy transfer and the difference in maximum value, a refined evaluation of the necessity of energy transfer of the single cell is achieved to ensure a more reasonable allocation of balancing resources. Considering the influence of voltage credibility, unnecessary balancing actions caused by voltage fluctuations are reduced, and the stability and reliability of the system are improved.

[0143] In one embodiment of the present invention, analyzing the influence of the load state on the balancing efficiency of the single cell and determining the balancing inadaptability corresponding to the single cell includes:

[0144] Analyzing the reduction of the voltage data through the correlation between the current data and the voltage data to determine the abnormal reduction degree corresponding to the voltage data;

[0145] Determining the equalization efficiency corresponding to the single cell according to the voltage change of the single cell during the historical equalization process;

[0146] Analyzing the correlation between the abnormal reduction degree under the load state and the change of the balancing efficiency, and determining the effect of the load state on the balancing efficiency according to the change correlation degree;

[0147] The balancing inadaptability corresponding to the single cell is determined according to the effect of the load state of the single cell at the current moment on the balancing efficiency and the effect of the minimum load state on the balancing efficiency.

[0148] Among them, simply performing balancing control based on voltage data may lead to over-balancing due to changes in the load state of the battery pack. Under actual high-load discharge conditions, the battery voltage will drop rapidly due to the internal resistance voltage drop caused by the large current, which may trigger unnecessary balancing actions. The balancing trigger comes from the large voltage difference. When the voltage difference between batteries exceeds the balancing threshold, balancing action will be performed. Therefore, it is necessary to capture this abnormal voltage state to avoid invalid balancing.

[0149] The correlation between the current data and the voltage data refers to the mathematical correlation between the current data and the voltage data, which is usually measured by calculating the correlation coefficient between the two.

[0150] Among them, the degree of abnormal reduction refers to an indicator that describes whether the degree of voltage reduction under specific conditions exceeds the normal range, and is used to evaluate whether there is an abnormal voltage drop phenomenon in the single cell battery.

[0151] Among them, the historical balancing process refers to a series of operation records of the single cell in the past balancing control process, including voltage changes, current flows, etc. By analyzing the historical balancing process, we can understand the balancing performance of the single cell under different load conditions.

[0152] When determining the balancing efficiency corresponding to the single cell according to the voltage change of the single cell during the historical balancing process, the voltage change amplitude of the single cell during the historical balancing process can be counted; and then the balancing efficiency is calculated according to the voltage change amplitude (e.g., the smaller the voltage change, the higher the balancing efficiency).

[0153] The effect of the load state on the balancing efficiency refers to the degree of influence of the load state on the balancing efficiency of the single cell.

[0154] The minimum load state refers to the working state of the single cell under the minimum load condition, which can be used as a benchmark to compare the changes in balanced efficiency under other load states.

[0155] For example, there is a certain correlation between current and voltage. If an abnormal condition occurs, such as causing an internal resistance voltage drop, the voltage will suddenly drop. Figure 3 , Figure 3 A schematic diagram of abnormal voltage drop provided by an embodiment of the present invention, in Figure 3 In the process, the voltage suddenly drops, which destroys the relationship between current and voltage. The abnormal degree of reduction corresponding to the voltage data can be obtained according to the changes in current and voltage.

[0156] Exemplarily, the expression of the reduced abnormality degree corresponding to the voltage data may be:

[0157]

[0158] Among them, F i A represents the abnormal degree of decrease corresponding to the voltage data of the i-th single cell at the current moment; i Indicates the necessary degree of energy transfer corresponding to the i-th single cell. The larger the value, the lower the battery voltage, and the more suitable the i-th single cell is as an energy receiver. However, the low battery voltage at this time is due to an abnormal condition and cannot reflect the actual battery charge state; E i represents the voltage data of the ith single cell within the preset neighborhood at the current moment; I i represents the current data of the i-th single cell within the preset neighborhood at the current moment; ρ(E i ,I i ) represents the correlation between the current data and the voltage data of the ith single cell within the preset neighborhood at the current moment, which may be the Pearson correlation coefficient between the current and the voltage; It represents the correlation between the current data and voltage data of the ith single cell during the historical balancing process, and is also the Pearson correlation coefficient between current and voltage.

[0159] in, It represents the difference in the correlation between the current data and the voltage data of the ith single cell at the current moment and in the historical balancing process. The larger the value of this formula is, the voltage of the single cell may be in an abnormal state and cannot reflect the real battery state.

[0160] in, The larger the value is, the more likely the voltage of the single battery is abnormal and cannot reflect the actual battery status.

[0161] For example, if the voltage of a single cell is in an abnormal state caused by an internal resistance voltage drop, the voltage drops rapidly as an energy receiver, but the original charge state of the battery does not require immediate energy reception, which will cause it to become an energy transferor after the balancing action, and frequently perform useless balancing. The balancing efficiency caused by this abnormal voltage state will be very low. By analyzing the voltage changes of each single cell in the historical balancing process, the balancing efficiency corresponding to the single cell can be determined.

[0162] For example, the equalization efficiency corresponding to the single cell may be expressed as:

[0163]

[0164] Among them, X i,j represents the balancing efficiency of the ith single cell in the jth historical balancing process; bE i,j represents the initial equalization voltage value of the ith single cell in the jth historical equalization process; eE i,j represents the ending equalization voltage value of the ith single cell in the jth historical equalization process; Ti,j It represents the balancing time of the i-th single cell in the j-th historical balancing process.

[0165] in, It represents the efficiency of energy transfer completion (i.e. voltage reaching equilibrium state) of the ith single cell during the jth historical balancing process. The larger the value of this formula, the higher the balancing efficiency.

[0166] For example, the main reason for frequent ineffective balancing of a battery pack is that the single cell is affected by the load state, and the voltage cannot truly reflect the battery charge state, resulting in erroneous balancing action. Therefore, in the clustering results, the relationship between the abnormal voltage drop under the load state at each moment in the high-load cluster and the balancing efficiency of the balancing process experienced is analyzed. It can be concluded that the relationship between the abnormal voltage drop and the corresponding balancing efficiency at the historical moment of the same load state corresponding to the cluster to which each single cell belongs at the current moment.

[0167] For example, the effect of the load state on the balancing efficiency may be expressed as follows:

[0168] G i =exp(-DTW(F i ′ ,exp(-X i )))

[0169] Among them, G i Indicates the effect of the load state of the i-th single cell on the balancing efficiency; F i ′ represents the abnormal degree sequence of voltage data reduction corresponding to all historical balancing processes in the load state to which the voltage data of the i-th single cell at the current moment belongs; X i represents the equilibrium efficiency sequence of the i-th single cell in all historical balancing processes; exp is an exponential function; DTW represents dynamic time warping.

[0170] Among them, DTW(F i ′ ,exp(-X i )) represents the correlation between the abnormal degree of voltage drop of all historical balancing processes and the balancing efficiency in the load state to which the voltage data of the i-th single cell at the current moment belongs. The smaller the formula is, the greater the impact of the voltage drop on the balancing efficiency.

[0171] Among them, exp(-DTW(F i ′ ,exp(-X i The larger the value of ))), the greater the effect of the load state on the balancing efficiency.

[0172] For example, the voltage of the battery reflects the real-time level of its working state, and the change is relatively stable and predictable. At this time, the load state has a low impact on the balancing efficiency. The balancing control of the lowest load state is used as a basis to determine whether the load state of the single cell at the current moment is suitable for energy reception. According to the comprehensive impact of the load state in the load state cluster to which the single cell belongs at the current moment on the balancing efficiency, the balancing unsuitability of the load state of the single cell at the current moment can be determined.

[0173] Exemplarily, the equalization inadaptability corresponding to the single cell may be expressed as:

[0174]

[0175] Among them, Y i represents the balancing inadaptability corresponding to the i-th single cell; G i represents the effect of the load state of the ith single cell on the balancing efficiency; G i ′ It represents the effect of the minimum load state corresponding to the i-th single cell on the balancing efficiency.

[0176] in, The larger the value is, the less suitable the single cell is for balancing at the current moment.

[0177] In this embodiment, by analyzing the correlation between current and voltage and the voltage change during the historical balancing process, the balancing efficiency of the single cell can be evaluated more accurately. Combined with the correlation between the reduction of abnormality and the change in balancing efficiency, the impact of the load state on the balancing efficiency is comprehensively evaluated to ensure that the balancing strategy is more reasonable. Introducing the reduction of abnormality and historical balancing data as supplementary indicators reduces the risk of misjudgment caused by a single factor.

[0178] In one embodiment of the present invention, determining the balancing priority corresponding to the single battery according to the necessary degree of energy transfer and the balancing inadaptability includes:

[0179] Determining the balancing adaptability of the single battery at the current moment according to the balancing unadaptability;

[0180] The balancing priority corresponding to the single cell is determined in combination with the necessary degree of energy transfer of the single cell at the current moment and the balancing adaptability.

[0181] For example, during the operation of the battery pack, the single cell pair with the largest voltage difference needs to be balanced. When the single cell is in a high load state, the voltage will drop rapidly due to the internal resistance voltage drop, causing it to be misjudged as the optimal energy transfer target. Therefore, the balancing priority of the single cell can be dynamically adjusted by analyzing the impact of the battery's current load state on the balancing efficiency.

[0182] Exemplarily, the balancing priority corresponding to the single cell is expressed as follows:

[0183] Z i =A i ×(1-Y i )

[0184] Among them, Z i Indicates the balancing priority corresponding to the i-th single cell; A i Indicates the necessary degree of energy transfer corresponding to the i-th single cell.

[0185] Among them, (1-Y i ) represents the balancing adaptability of the ith single cell at the current moment. The larger the value, the more suitable the single cell is for balancing at the current moment.

[0186] Among them, A i ×(1-Y i ) is larger, the higher the balancing priority of the i-th single cell is, and the more suitable it is for balancing at the current moment.

[0187] In this embodiment, by comprehensively considering the necessary degree of energy transfer and the adaptability of balancing, the balancing requirements of the single cells can be evaluated more comprehensively, avoiding misjudgment due to a single indicator, and dynamically adjusting the balancing priority according to the current energy state and load characteristics to ensure that the balancing control strategy can adapt to different working conditions.

[0188] In one embodiment of the present invention, the balancing control of some single cells in the large-capacity battery pack based on the balancing priority corresponding to each single cell includes:

[0189] When the voltage difference between the plurality of single cells is greater than a preset voltage difference threshold, determining an energy transfer path according to the balancing priority corresponding to each of the single cells;

[0190] Through the energy transfer path, energy is transferred from a single cell with a high voltage to a single cell with the highest balancing priority by using an inductor, so as to achieve balancing control.

[0191] Among them, the energy transfer path refers to the specific path or method used to realize the transfer of energy from one single cell to another in the balancing control process. It can clarify the direction and path of energy flow and ensure the efficiency and accuracy of the balancing operation.

[0192] Among them, inductance is an energy storage element that can store and release energy through the principle of electromagnetic induction. It is often used to achieve energy transfer in balancing control. By utilizing the energy storage characteristics of inductance, the energy of high-voltage single cells is transferred to low-voltage single cells, thereby achieving voltage balance.

[0193] For example, suppose there is a large-capacity battery pack composed of 3 single cells, and the voltage data (unit: V) and balancing priority of each single cell are: single cell 1: voltage = 4.2V, balancing priority = 0.8; single cell 2: voltage = 4.0V, balancing priority = 0.5; single cell 3: voltage = 3.8V, balancing priority = 0.2. Assuming the preset voltage difference threshold is 0.3V: the voltage difference between single cell 1 and single cell 3 = 4.2-3.8 = 0.4V> 0.3V, then balancing control is required. According to the balancing priority, select the target battery: high voltage single cell: single cell 1 (highest voltage); target single cell: single cell 3 (highest balancing priority). Use inductance as the energy transfer medium, store the energy in single cell 1 into the inductor; release the energy in the inductor into single cell 3. After the energy transfer is completed, the voltage is redistributed as follows: single cell 1: the voltage drops to 4.0V; single cell 3: the voltage rises to 4.0V.

[0194] It should be noted that during the balancing process, the status of the single cells can be continuously monitored and the priority calculation results can be dynamically updated to ensure that the balancing operation is adjusted in real time to adapt to load changes and avoid over-balancing or under-balancing.

[0195] In this embodiment, the energy transfer path planning driven by the equalization priority can more accurately select the single battery that needs to be equalized, avoiding unnecessary equalization operations. Using inductance as the energy transfer medium reduces energy loss and improves energy transfer efficiency.

[0196] Figure 4 A schematic diagram of a large-capacity battery pack state monitoring and balancing control device provided by an embodiment of the present invention. The device can be applied to Figure 1 The device may also be applicable to other exemplary implementation environments and specifically configured in other devices, and this embodiment does not limit the implementation environment to which the device is applicable.

[0197] like Figure 4 As shown, the exemplary large-capacity battery pack state monitoring and balancing control device includes:

[0198] The data acquisition module 401 is used to acquire monitoring data of multiple single cells in a large-capacity battery pack;

[0199] A load state determination module 402, configured to determine a load state corresponding to each of the single cells based on the monitoring data of the multiple single cells;

[0200] The balancing priority determination module 403 is used to analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells to balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability;

[0201] The balancing control module 404 is used to perform balancing control on some single cells in the large-capacity battery pack based on the balancing priority corresponding to each single cell.

[0202] In this exemplary large-capacity battery pack state monitoring and balancing control device, the load state of each single cell is determined based on the monitoring data of multiple single cells in the large-capacity battery pack, which not only takes into account the voltage value but also combines the load characteristics, so as to more comprehensively evaluate the actual working state of the single cell, effectively reduce the interference of load changes on voltage judgment, and improve the accuracy of state evaluation; by analyzing the impact of the load state on the balancing efficiency, the adaptability of each single cell for balancing at the current moment is determined, avoiding the limitation of relying solely on the voltage value for balancing judgment, ensuring that the balancing action is more reasonable and efficient, avoiding misjudgment caused by the load state, and thus improving the overall balancing efficiency; according to the balancing adaptability of each single cell, its corresponding balancing priority is determined, and the single cell that most needs balancing can be processed first, thereby improving the efficiency of balancing control, reducing unnecessary balancing operations, and extending the service life of the battery pack; based on the balancing priority of each single cell, balancing control is performed on some single cells, which can concentrate resources to deal with key issues, improve the overall effect of balancing control, ensure that limited balancing resources are used first for the single cells that need it most, and avoid resource dispersion.

[0203] It should be noted that the large-capacity battery pack state monitoring and balancing control device provided in the above embodiment and the large-capacity battery pack state monitoring and balancing control method provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment, and will not be repeated here. In actual applications, the large-capacity battery pack state monitoring and balancing control device provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0204] An embodiment of the present invention also provides an electronic device, comprising: one or more processors; a storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the electronic device implements the large-capacity battery pack status monitoring and balancing control method provided in the above-mentioned embodiments.

[0205] Figure 5 This is a schematic diagram of the structure of a computer system suitable for electronic equipment provided by one embodiment of the present invention. It should be noted that: Figure 5 The computer system 500 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0206] like Figure 5 As shown, the computer system 500 includes a central processing unit (CPU) 501, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 502 or the program loaded from the storage part 508 to the random access memory (RAM) 503, such as executing the method described in the above embodiment. In the RAM 503, various programs and data required for system operation are also stored. The CPU 501, the ROM 502 and the RAM 503 are connected to each other through a bus 504. The input / output (I / O) interface 505 is also connected to the bus 504.

[0207] The following components are connected to the I / O interface 505: an input section 506 including a keyboard, a mouse, etc.; an output section 507 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker; a storage section 508 including a hard disk, etc.; and a communication section 509 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 509 performs communication processing via a network such as the Internet. A drive 510 is also connected to the I / O interface 505 as needed. A removable medium 511, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 510 as needed so that a computer program read therefrom is installed into the storage section 508 as needed.

[0208] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication part 509, and / or installed from a removable medium 511. When the computer program is executed by a central processing unit (CPU) 501, various functions defined in the system of the present invention are executed.

[0209] It should be noted that the computer-readable medium shown in the embodiment of the present invention may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present invention, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable computer program. This propagated data signal may take a variety of forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate or transmit a program for use by or in conjunction with an instruction execution system, apparatus or device. A computer program contained on a computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0210] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Among them, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0211] The units involved in the embodiments of the present invention may be implemented by software or hardware, and the units described may also be arranged in a processor. The names of these units do not, in some cases, limit the units themselves.

[0212] Another aspect of the present invention further provides a large-capacity battery pack state monitoring and balancing control system, the system comprising a computer-readable storage medium, the computer-readable storage medium storing a plurality of instructions, the instructions being suitable for a processor to load to execute the steps in any large-capacity battery pack state monitoring and balancing control method provided in the embodiments of the present invention. The computer-readable storage medium may be included in the electronic device described in the above embodiments, or may exist independently without being assembled into the electronic device.

[0213] It should be noted that the sequence of the above embodiments of the present invention is for description only and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0214] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A method for monitoring and balancing the state of a large-capacity battery pack, characterized in that: The method comprises: Obtain monitoring data of multiple single cells in a large-capacity battery pack; Determining a load state corresponding to each of the single cells based on the monitoring data of the multiple single cells; Analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells for balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability; Based on the balancing priority corresponding to each of the single cells, balancing control is performed on some of the single cells in the large-capacity battery pack.

2. The large-capacity battery pack state monitoring and balancing control method according to claim 1, characterized in that: After the monitoring data of the plurality of single cells in the large-capacity battery pack are obtained, the method further includes: removing random noise from the monitoring data to obtain first monitoring data; Performing filtering optimization on the first monitoring data to obtain second monitoring data; The second monitoring data is subjected to temperature compensation and aging effect correction to obtain preprocessed monitoring data, and the preprocessed monitoring data is used to determine a load state corresponding to the large-capacity battery pack.

3. The large-capacity battery pack state monitoring and balancing control method according to claim 1, characterized in that: The monitoring data includes current data, and determining the load state corresponding to each of the single cells based on the monitoring data of the multiple single cells includes: For each of the single cells, extract a current segment from the current data, and determine a current mean value corresponding to the current segment; According to a preset neighborhood radius and a minimum number of samples, the current mean value is clustered to obtain a clustering result, and the load state corresponding to each of the single cells is determined according to the clustering result.

4. The large-capacity battery pack state monitoring and balancing control method according to claim 3, characterized in that: The monitoring data includes voltage data, and the analyzing the influence of the load state corresponding to each of the single cells on the balancing efficiency, determining the adaptability of each of the single cells for balancing at the current moment, and determining the balancing priority corresponding to each of the single cells according to the adaptability, includes: Determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within a preset neighborhood range at the current moment; Analyzing the influence of the load state on the equalization efficiency of the single cell, and determining the equalization inadaptability corresponding to the single cell; The balancing priority corresponding to the single battery is determined according to the necessary degree of energy transfer and the balancing inadaptability.

5. The large-capacity battery pack state monitoring and balancing control method according to claim 4, characterized in that: The determining the necessary degree of energy transfer corresponding to the single battery according to the change of the voltage data within the preset neighborhood range at the current moment includes: Taking the average value of the voltage data within a preset neighborhood at the current moment as the energy transfer demand corresponding to the single battery; Taking the variance of the voltage data within a preset neighborhood at the current moment as the voltage credibility corresponding to the single battery; Determining the necessity of energy transfer corresponding to the single battery in combination with the energy transfer requirement and the voltage credibility; The degree of necessity of energy transfer corresponding to the single cell is determined according to a difference between the necessity of energy transfer corresponding to the single cell and a maximum value of the necessity of energy transfer corresponding to all the single cells.

6. The large-capacity battery pack state monitoring and balancing control method according to claim 4, characterized in that: The analyzing the influence of the load state on the equalization efficiency of the single cell to determine the equalization inadaptability corresponding to the single cell includes: Analyzing the reduction of the voltage data through the correlation between the current data and the voltage data to determine the abnormal reduction degree corresponding to the voltage data; Determining the equalization efficiency corresponding to the single cell according to the voltage change of the single cell during the historical equalization process; Analyzing the correlation between the abnormal reduction degree under the load state and the change of the balancing efficiency, and determining the effect of the load state on the balancing efficiency according to the change correlation degree; The balancing inadaptability corresponding to the single cell is determined according to the effect of the load state of the single cell at the current moment on the balancing efficiency and the effect of the minimum load state on the balancing efficiency.

7. The large-capacity battery pack state monitoring and balancing control method according to claim 4, characterized in that: The determining, according to the necessary degree of energy transfer and the balancing inadaptability, the balancing priority corresponding to the single battery includes: Determining the balancing adaptability of the single battery at the current moment according to the balancing unadaptability; The balancing priority corresponding to the single cell is determined in combination with the necessary degree of energy transfer of the single cell at the current moment and the balancing adaptability.

8. The large-capacity battery pack state monitoring and balancing control method according to claim 1, characterized in that: The step of performing balancing control on some of the single cells in the large-capacity battery pack based on the balancing priority corresponding to each of the single cells includes: When the voltage difference between the plurality of single cells is greater than a preset voltage difference threshold, determining an energy transfer path according to the balancing priority corresponding to each of the single cells; Through the energy transfer path, energy is transferred from a single cell with a high voltage to a single cell with the highest balancing priority by using an inductor, so as to achieve balancing control.

9. A large-capacity battery pack state monitoring and balancing control system, characterized in that: The system includes a computer-readable storage medium storing a plurality of instructions suitable for loading by a processor to execute the steps in the large-capacity battery pack state monitoring and balancing control method as claimed in any one of claims 1 to 8.

10. A large-capacity battery pack state monitoring and balancing control device, characterized in that: The device comprises: A data acquisition module, used to acquire monitoring data of multiple single cells in a large-capacity battery pack; A load state determination module, used for determining the load state corresponding to each of the single cells based on the monitoring data of the multiple single cells; A balancing priority determination module, used to analyze the influence of the load state corresponding to each of the single cells on the balancing efficiency, determine the adaptability of each of the single cells for balancing at the current moment, and determine the balancing priority corresponding to each of the single cells according to the adaptability; The balancing control module is used to perform balancing control on some single cells in the large-capacity battery pack based on the balancing priority corresponding to each single cell.

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