Battery management system and method for redundancy collection

Abstract

The invention relates to a redundancy collection battery management system and method. The system comprises a first voltage acquisition unit, a second voltage acquisition unit and a control unit, the first voltage acquisition unit is used for acquiring a first voltage of a target cell, and the second voltage acquisition unit is used for acquiring a second voltage of the target cell. And the control unit is used for receiving the first voltage and the second voltage and carrying out weighted fusion calculation based on the deviation between the first voltage and the second voltage to obtain a final voltage value of the target battery cell. By adopting the system, when single-path voltage acquisition fails due to interference or faults, accurate battery voltage can be output through another path of redundancy acquisition and fusion algorithm, and the fault-tolerant capability of a voltage acquisition link and the reliability of a battery management system are effectively improved.

Description

Technical Field

[0001] This application relates to the field of battery management technology, and in particular to a battery management system and method for redundant data acquisition. Background Technology

[0002] The Battery Management System (BMS) is a core component that ensures the safe, stable, and efficient operation of a battery pack. One of its core functions is to collect the voltage of each cell in the battery pack. The accuracy of the voltage data directly affects the reliability of functions such as battery state assessment, equalization management, and overcharge and over-discharge protection.

[0003] Currently, the common approach for battery management systems to acquire battery voltage is to use a single analog front-end (AFE) chip and its sampling channels. This approach uses the analog-to-digital converter (ADC) inside the AFE chip to measure the voltage of each cell sequentially or synchronously.

[0004] However, in practical applications, when the AFE chip's acquisition channel experiences disconnections or electromagnetic interference, a single acquisition path may fail to obtain valid voltage data. This can affect the BMS's accurate judgment of the battery status and even lead to risks such as malfunctions in charge / discharge control and cell damage. Therefore, improving the robustness and reliability of the voltage acquisition circuit under interference and certain fault conditions to ensure accurate and usable cell voltage data has become a pressing technical problem in this field. Summary of the Invention

[0005] Therefore, it is necessary to provide a redundant acquisition battery management system and method that can improve the reliability of cell voltage acquisition in order to address the above-mentioned technical problems.

[0006] In a first aspect, this application provides a redundant voltage acquisition battery management system, the battery management system including a first voltage acquisition unit, a second voltage acquisition unit, and a control unit, the first voltage acquisition unit and the second voltage acquisition unit being respectively connected to a battery pack, the battery pack including multiple cells; the control unit being respectively connected to the first voltage acquisition unit and the second voltage acquisition unit.

[0007] The first voltage acquisition unit is used to acquire the first voltage of the target battery cell;

[0008] The second voltage acquisition unit is used to acquire the second voltage of the target battery cell;

[0009] The control unit is used to receive the first voltage and the second voltage, and perform a weighted fusion calculation based on the deviation between the two to obtain the final voltage value of the target cell.

[0010] In one embodiment, the second voltage acquisition unit includes a resistor divider network and a multiplexing circuit; the multiplexing circuit is connected to the resistor divider network; the first voltage acquisition unit is connected to the second voltage acquisition unit.

[0011] The resistor voltage divider network is connected to the battery pack and is used to divide the voltage of the battery pack and form multiple voltage divider nodes;

[0012] The first voltage acquisition unit sends a selection command to the multiplexing circuit to control the multiplexing circuit to select the voltage divider node corresponding to the target cell and acquire the voltage value of the circuit being conducted to obtain the second voltage.

[0013] In one embodiment, the control unit is configured to:

[0014] The second voltage of the target cell is obtained by the difference between the first total voltage corresponding to the first voltage divider node selected at the current time and the second total voltage corresponding to the adjacent voltage divider node selected at the previous acquisition time.

[0015] In one embodiment, the first voltage acquisition unit includes a first analog front-end chip, and the second voltage acquisition unit includes a second analog front-end chip; the first analog front-end chip and the second analog front-end chip acquire voltage from the same cell through different voltage acquisition channels.

[0016] In one embodiment, when the battery pack is in a charging or discharging state, the control unit is configured to:

[0017] When either the first voltage or the second voltage experiences a jump that is opposite to the voltage change trend of the other cells, while the other voltage has the same change trend as the other cells, the voltage with the same change trend is taken as the final voltage.

[0018] In one embodiment, the control unit is further configured to:

[0019] When both the first voltage and the second voltage change in the same direction, the moving average of the voltage change of all cells in the battery pack at the current moment is calculated. The deviation of the voltage change value of the first voltage and the second voltage from the moving average is calculated respectively. Based on the comparison result of the deviation with a first preset threshold, the first voltage and the second voltage are assigned weights and weighted calculation is performed to obtain the final voltage.

[0020] In one embodiment, the formula for weighted fusion calculation of the first voltage and the second voltage is as follows:

[0021]

[0022] in, For the final voltage, The first voltage, The second voltage, This is the jump value corresponding to the first voltage. This is the jump value corresponding to the second voltage. The first preset threshold is used.

[0023] In one embodiment, when the battery pack is in a static state, the control unit is further configured to:

[0024] Determine whether the first voltage and the second voltage have undergone a jump in amplitude exceeding a second preset threshold relative to their historical values, and take the collected voltage whose jump amplitude does not exceed the second preset threshold as the final voltage.

[0025] Secondly, this application also provides a battery management method for redundant acquisition, used in a system as described in any of the first aspects above, comprising:

[0026] Obtain the first and second voltages of the target cell in the battery pack;

[0027] Calculate the deviation between the first voltage and the second voltage;

[0028] The final voltage of the target battery cell is obtained by performing a weighted fusion calculation based on the deviation.

[0029] In one embodiment, the weighted fusion calculation based on the deviation to obtain the final voltage of the target cell includes:

[0030] When both the first voltage and the second voltage change in the same direction, calculate the moving average of the voltage changes of all cells in the battery pack at the current moment.

[0031] Calculate the deviations of the jump values ​​of the first voltage and the second voltage relative to the moving average value, respectively;

[0032] Based on the comparison result between the deviation and the first preset threshold, weights are assigned to the first voltage and the second voltage;

[0033] The first voltage and the second voltage are weighted according to the assigned weights to obtain the final voltage.

[0034] The aforementioned redundant voltage acquisition battery management system and method, by introducing a first voltage acquisition unit and a second voltage acquisition unit, constructs a redundant voltage acquisition system architecture. When the data measurement of one acquisition channel is abnormal, the other acquisition channel can still provide valid voltage data, thereby improving the availability and robustness of voltage acquisition. The control unit can dynamically correct the two data channels by performing data weighted fusion calculation based on voltage data deviation, thereby improving the accuracy of voltage acquisition. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a structural diagram of a battery management system with redundant data acquisition according to one embodiment.

[0037] Figure 2 This is a battery management system module structure based on a multi-channel gating circuit in one embodiment;

[0038] Figure 3 This is a modular structure of a resistor voltage divider network in a specific embodiment;

[0039] Figure 4 This is a module structure of the second voltage acquisition unit in a preferred embodiment;

[0040] Figure 5 This is a battery management system module structure based on an analog front-end chip in another embodiment;

[0041] Figure 6 A flowchart illustrating the steps of a battery management method for redundant data acquisition according to one embodiment;

[0042] Figure 7 This is a flowchart of the steps for weighted fusion calculation based on deviation in one embodiment. Detailed Implementation

[0043] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0044] Unless otherwise defined, 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 application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0045] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0046] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0047] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0048] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0049] like Figure 1 As shown, the redundant voltage acquisition battery management system of this embodiment includes a first voltage acquisition unit 100, a second voltage acquisition unit 200, and a control unit 300. The battery pack 400 includes multiple cells (B1, B2, ..., Bn) connected in series. The first voltage acquisition unit 100 and the second voltage acquisition unit 200 are electrically connected to the corresponding cell connection points in the battery pack 400, and the control unit 300 is connected to the first voltage acquisition unit 100 and the second voltage acquisition unit 200.

[0050] It should be noted that the "redundancy" referred to in this method is relative to the traditional single-path voltage acquisition scheme. In traditional battery management systems, a single voltage acquisition unit (such as an AFE chip) is typically used to measure the voltage of all cells. If this acquisition unit or related circuit fails or is interfered with, the voltage detection function of the battery management system will be at risk of failure. Therefore, this scheme adds a second voltage acquisition unit 200 to the single acquisition path. The two units are hardware-independent, thus forming a redundant structure. The control unit 300 performs data fusion processing on the data from the two independent sources to ensure the accuracy and reliability of the voltage acquisition information.

[0051] The first voltage acquisition unit 100 is used to acquire the first voltage of the target cell. Its function is to directly or indirectly measure the cell voltage and convert the analog signal into a digital quantity that can be processed by the control unit 300. In one optional implementation, the first voltage acquisition unit 100 may include an analog front-end chip that integrates an analog multiplexer and an analog-to-digital converter, capable of acquiring the terminal voltage of each cell through polling or synchronous methods. In another optional implementation, the first voltage acquisition unit 100 may also consist of discrete operational amplifiers, analog-to-digital converters, and related filtering and protection circuits.

[0052] The second voltage acquisition unit 200 is used to acquire the second voltage of the same target cell. The acquisition principle or signal path of the second voltage acquisition unit 200 is independent of that of the first voltage acquisition unit 100, thus constituting hardware redundancy. For example, in one optional implementation, the second voltage acquisition unit 200 can be a voltage detection circuit based on a multiplexing circuit and a resistor divider network. This network divides the total voltage of the battery pack and indirectly calculates the voltage of a single cell through subsequent processing. In another optional implementation, the second voltage acquisition unit 200 can also be another independent AFE sampling system, whose sampling channel, reference source, or signal conditioning circuit is independent of that of the first voltage acquisition unit 100.

[0053] The control unit 300 can be a microcontroller unit (MCU), a microprocessor unit (MPU), or a digital signal processor (DSP). The control unit can directly or indirectly receive voltage data acquired from the first voltage acquisition unit and the second voltage acquisition unit, and perform a weighted fusion algorithm based on the deviation between the two data streams to determine the final voltage value of the target cell being measured.

[0054] The deviation between the two data streams can be the absolute difference between the sampled values ​​at the same time, or it can be the difference in the trend calculated based on historical data.

[0055] For example, the principle of the weighted fusion algorithm can be to assign weight coefficients to the two voltage paths based on the magnitude or characteristics of the deviation calculated in real time. When the data consistency is high, the weights are close; when the deviation is large, it indicates that one of the data paths may be unreliable, and the algorithm adaptively reduces the weight of that data path while increasing the weight of the other data path. Finally, the final voltage value of the target cell is obtained by weighted calculation.

[0056] This embodiment enhances the fault tolerance of voltage acquisition by setting up two independent acquisition units. When one channel fails due to fault or interference, the system can still obtain voltage information through the other channel, thus improving the fault tolerance of voltage acquisition. By combining the weighted fusion algorithm of the control unit, weighted fusion is performed based on the deviation of the two data channels. This effectively identifies and suppresses erroneous data caused by transient interference, channel noise, or gradual drift, making the final output voltage value closer to the true value and significantly improving the reliability of voltage acquisition.

[0057] In some exemplary embodiments, the second voltage acquisition unit 200 can implement hardware redundancy based on a multiplexing circuit architecture. For example... Figure 2 As shown, in the redundant acquisition battery management system of this embodiment, the second voltage acquisition unit 200 includes a resistor voltage divider network 210 and a multiplexing circuit 220.

[0058] A resistor-based voltage divider network 210 is connected to the total voltage output terminal of the battery pack 400. This network is used to divide the total voltage of the battery pack 400, forming a voltage divider node at the connection point of every two adjacent resistors. The potentials of these voltage divider nodes are proportional to the cumulative voltage of the battery pack from the first cell to the nth cell. By properly designing the resistor values, the voltage of each voltage divider node can be made to fall within the input range of subsequent processing circuits.

[0059] The input terminals of the multiplexing circuit 220 are connected one-to-one with each voltage divider node of the resistor voltage divider network 210, while the output terminal is connected to one or more general-purpose input / output ports or dedicated analog input ports of the first voltage acquisition unit 100. The multiplexing circuit 220 can be one or more multiplexed analog switch chips.

[0060] In addition, the first voltage acquisition unit 100 is also connected to the control terminal of the multiplexing circuit 220 via a set of digital control lines (e.g., address lines A, B, and C). The first voltage acquisition unit 100 sends specific gating commands through the control lines to control the switching action inside the multiplexing circuit 220, thereby connecting its common output terminal to a designated voltage divider node.

[0061] Specifically, when the system needs to acquire the second voltage data of the target cell Bk, the control logic within the control unit 300 or the first voltage acquisition unit 100 first determines the voltage divider node to be selected. Then, the first voltage acquisition unit 100 sends a signal corresponding to the multiplexing circuit 220. The strobe command switches its internal switch to the position corresponding to the input. On the connected channel, at this time, The voltage divider signal at the point is conducted to the output terminal and acquired by the ADC port of the first voltage acquisition unit 100. This signal is then measured at the node. and The voltage difference between the two voltages can be used to obtain the value of the second voltage.

[0062] In one specific embodiment, the resistor divider network is as follows: Figure 3 As shown, it consists of multiple voltage divider circuit modules. The input terminals are connected to the connection points of each cell in the battery pack to be measured. Each voltage divider circuit module consists of two resistors connected in series. The output terminals of the voltage divider circuit modules together form a voltage divider node, which is connected to a multiplexing circuit.

[0063] In another preferred embodiment, two CD4051BPWR chips are used to form a multiplexing circuit for acquiring the voltage of 14 battery cells. The first voltage acquisition unit uses an ADBMS1818 analog front-end chip. The connection circuit diagram of one of the CD4051BPWR chips is shown below. Figure 4 As shown, the CD4051BPWR is powered by the VREG (5V) pin of the AFE chip. The AFE chip selects the CD4051BPWR's internal single-pole multi-throw (SPMWOT) switch array to the corresponding I / O ports 1 to 7 via address inputs A, B, and C. For example, when ABC=000, the switch is I / O 0; when ABC=001, the switch is I / O 1; and when ABC=111, the switch is I / O 7. Its output pin 3 is connected to the AFE chip's GPIO8 channel to complete voltage acquisition. Filtering circuits are also connected to the chip's inputs I / O 1 to I / O 7 to filter high-frequency interference in the voltage signal. A 7.5V Zener diode is connected to the VREG pin to ensure that the VREG pin voltage does not exceed 7.5V, thus preventing damage to the resistor due to overvoltage. Capacitor C75 is the filter capacitor.

[0064] It is understandable that the AFE chip can drive two multiplexer chips to select the switching state of 16 I / O ports through the three binary control signals of the A, B, and C address input terminals.

[0065] It should be noted that since the multiplexing circuit 220 can only connect its single output terminal to a voltage divider node at any given time, the voltage of the target cell Bk can be calculated using the timing proximity relationship.

[0066] In one exemplary embodiment, the system controls a multiplexing circuit to cyclically select the first to nth voltage divider nodes at millisecond intervals, and collects the total voltage to ground of each voltage divider node. At the first acquisition moment, the system selects and measures the node. The total voltage of cells from the first to the (k-1)th cell was obtained. The value is then stored in memory. At the next data acquisition moment, the control unit retrieves the value acquired at the current moment. (Representing the total voltage of sections 1 to k) and the stored The second voltage of the target cell Bk can then be calculated. get.

[0067] In other embodiments, the first voltage acquisition unit 100 and the second voltage acquisition unit 200 may both adopt an architecture based on an analog front-end chip to achieve hardware redundancy of another architecture. Figure 5 Another schematic diagram of the redundant acquisition battery management system according to this embodiment is shown.

[0068] In this embodiment, the first voltage acquisition unit 100 specifically includes a first analog front-end chip 110, and the second voltage acquisition unit 200 includes a second analog front-end chip 230. Both can use the same model of chip to simplify the design, or they can use chips from different manufacturers or of different models to reduce the risk of common failure.

[0069] The first analog front-end chip 110 is directly connected to the connection points corresponding to each cell in the battery pack through the first set of voltage sampling channels. The second analog front-end chip is also connected to the connection points corresponding to each cell in the battery pack through its voltage sampling channel, which is independent of the first voltage acquisition chip. Therefore, for the same target cell to be measured, there are two different physical sampling paths.

[0070] In a preferred embodiment, both the first analog front-end chip and the second analog front-end chip are ADBMS1818, which has 18 voltage acquisition channels, and the voltage of 14 battery cells to be acquired is collected. Specifically, C0 and C1 of the second analog front-end chip are shorted, meaning the first acquisition channel is shorted. The voltage of the first battery cell is acquired starting from the second acquisition channel, and so on, until the 15th channel acquires the voltage of the 14th cell. Channels 16, 17, and 18 are shorted. The first analog front-end chip, starting from the first acquisition channel, sequentially acquires the voltage of the 1st to 14th battery cells, thus achieving staggered connection of the chip's sampling channels.

[0071] In this embodiment, the same set of measured signals is collected by two complete and independent analog front-end chip sampling systems, which achieves the technical effect of avoiding the phenomenon that the sampling voltage of individual channels is prone to jump due to circuit layout and anti-interference design defects in the analog front-end chip.

[0072] For any of the above embodiments, when the battery pack is in a dynamic operating state of charging or discharging, this embodiment provides a voltage data fusion algorithm executed by the control unit.

[0073] It is understandable that when a battery pack is charging or discharging, its internal cells should theoretically exhibit a voltage change trend in the same direction. For example, during constant current charging, the terminal voltage of all cells will gradually increase; during constant current discharging, the terminal voltage of all cells will gradually decrease. Therefore, if either the first voltage or the second voltage sampled voltage experiences a jump that is opposite to the voltage change trend of the other cells, while the other sampled voltage exhibits the same voltage change trend as the other cells, it indicates an anomaly in the sampling channel exhibiting a reverse jump. In this case, the final voltage of the target cell is selected as the value with the same voltage change trend.

[0074] Furthermore, in some embodiments, when the changing trends of the first and second voltages are consistent with the overall trend of the battery pack, neither data source exhibits a significant abnormal trend. However, their jump amplitudes may differ, potentially reflecting varying degrees of noise, interference, or minor channel errors. In this case, the control unit executes the following data fusion algorithm.

[0075] Specifically, the control unit first calculates the moving average of the voltage changes of all cells in the battery pack at the current moment. This moving average is calculated by summing the absolute values ​​of all cell voltage jumps and dividing by the total number of cells, reflecting the average magnitude of the overall voltage change of the battery pack within the current sampling interval.

[0076] Then, the deviations of the jump values ​​of the first and second voltages relative to the moving average are calculated separately. This deviation represents the degree to which the jump amplitude deviates from the group average. The jump value of the first voltage... The deviation value is The jump value of the second voltage The deviation value is .

[0077] Next, based on the deviation and the first preset threshold The comparison results are used to assign weights to the first and second voltages and perform a weighted calculation to obtain the final voltage. The preset threshold can be a voltage value designed considering factors such as system noise level and actual application scenario. The weight of the first voltage... Weight of the second voltage satisfy ,and , For deviation values ​​and The different comparison results can be categorized as follows:

[0078] like and The absolute values ​​are all less than or equal to If the jump between the two data streams is reasonable, then approximately equal weights can be assigned, or a simple average can be performed.

[0079] If the absolute value of the deviation of one of the data is less than or equal to The other path is greater than If the data with a large deviation is judged to be more susceptible to interference, then the data with a smaller absolute deviation should be assigned a higher weight, and vice versa.

[0080] like and The absolute values ​​are all greater than However, the two data points are different in size, indicating that both data sources have some anomalies, but the degree of anomaly differs. In this case, weights can be allocated inversely proportional to the magnitude of the deviation.

[0081] Finally, the control unit determines the weights according to the assigned weights. and For the first voltage Second voltage After weighted fusion calculation, the final voltage value is .

[0082] In this embodiment, by using the overall change of all cells as a benchmark, the values ​​of two independent sampling channels are compared and fused, which makes the voltage sampling data closer to the actual voltage value of the cells.

[0083] In an exemplary embodiment, in the weighted fusion calculation formula of the above embodiments, the weight of the first voltage is... Weight of the second voltage It can be determined by the following formula:

[0084] ;

[0085] ;

[0086] in, For the final voltage, The first voltage, For the second voltage, This is the jump value corresponding to the first voltage. This is the jump value corresponding to the second voltage. This is the first preset threshold. Therefore, the final voltage value of the target cell is:

[0087] .

[0088] It is understandable that in the above weight allocation method, the greater the deviation, the lower the weight; and the weight allocation is related to the deviation. The degree is inversely proportional to the extent.

[0089] By applying this formula, the control unit 300 can fuse the two redundant data streams to obtain a final voltage that is closer to the true value when both streams exhibit different degrees of anomalies, thereby enhancing the data reliability and system stability of the system under complex and dynamic interference environments.

[0090] In some embodiments, the battery management system provided in this solution further extends to scenarios where the battery pack is in a static operating state. The static operating state typically refers to a relatively stable state where the battery pack has neither charging nor discharging current, or the charging and discharging current is extremely small. In this state, the theoretical voltage values ​​of each cell should remain stable without any abrupt changes. Therefore, if a certain data acquisition method experiences a jump or a disconnection, it can be considered that this data acquisition method is erroneous. In this embodiment, the control unit is configured to perform the following logical operations:

[0091] Determine whether the first voltage and the second voltage have changed in magnitude exceeding a second preset threshold relative to their historical values, and take the collected voltage whose magnitude of the change does not exceed the second preset threshold as the final voltage.

[0092] Specifically, the system has a second preset threshold. This value can be determined based on factors such as system noise and ADC resolution in a static state. The control unit continuously receives and stores the historical sampling sequence of the target cell, performs transition detection, and compares it with... Compare the deviation values ​​with The different comparison results can be categorized as follows:

[0093] If only the first voltage is available absolute value of jump Exceeded Or only the second voltage absolute value of jump Exceeded If so, the control unit will use the other voltage source as the final voltage value.

[0094] If the voltage jumps of both paths do not exceed If the result is positive, it indicates that both data streams are normal and stable. The control unit 300 can choose either one as the final voltage value or use a simple averaging method for calculation.

[0095] If the voltage jumps of both paths exceed If this occurs, it indicates that there may be a global disturbance or a sudden change in battery status. In this case, the control unit 300 can trigger a more advanced diagnostic process or adopt other preset strategies.

[0096] In this embodiment, by detecting whether a single data stream changes under the static state of the battery, data errors caused by abnormal acquisition such as circuit noise or poor contact can be quickly identified. This enables the redundant acquisition circuit to continuously ensure the reliability of voltage sampling data under all operating conditions, further improving the robustness and fault tolerance of the battery management system at different operating stages.

[0097] Based on the same inventive concept, this application also provides a battery management method for implementing the redundant acquisition involved above. This method can be applied to the control unit in any of the foregoing system embodiments. The solution provided by this method is similar to the implementation scheme described in the above system embodiments. Therefore, the specific limitations in one or more battery management method embodiments for redundant acquisition provided below can be found in the limitations above, and will not be repeated here.

[0098] In one exemplary embodiment, such as Figure 6 As shown, a battery management method for redundant data acquisition is provided, including:

[0099] Step S501: Obtain the first voltage and the second voltage of the target cell in the battery pack.

[0100] The control unit obtains the first voltage of the target cell from the first voltage acquisition unit. And simultaneously acquire the second voltage of the same target cell from the second voltage acquisition unit. The first voltage and the second voltage are obtained through different hardware acquisition principles or paths, forming a redundant data source.

[0101] Step S502: Calculate the deviation between the first voltage and the second voltage.

[0102] Calculate the first voltage With the second voltage The difference between the two data points serves as an indicator of their consistency. This deviation can be the absolute difference between the two voltage values ​​within the current sampling period, or it can be a trend difference or rate of change difference calculated by combining historical data.

[0103] Step S503: Perform weighted fusion calculation based on the deviation to obtain the final voltage of the target cell.

[0104] Based on the aforementioned biases, a weighted fusion algorithm is executed to perform fusion based on the magnitude or characteristics of the biases. and Weights are assigned. A large deviation indicates low reliability of one data path, in which case the weight assigned to that path is reduced. Finally, the weights are summed using these weights to obtain the final voltage.

[0105] In this embodiment, by using weighted fusion calculation on the two collected voltages, even if interference or failure occurs in one collected voltage, the system can still calculate a relatively reliable final voltage based on the other data and deviation analysis.

[0106] Furthermore, in some embodiments, such as Figure 7 As shown, the above weighted fusion calculation based on deviation to obtain the final voltage of the target cell specifically includes the following steps:

[0107] Step S601: When both the first voltage and the second voltage change in the same direction, calculate the moving average of the voltage changes of all cells in the battery pack at the current moment.

[0108] Step S602: Calculate the deviations of the jump values ​​of the first voltage and the second voltage relative to the moving average values, respectively.

[0109] Step S603: Based on the comparison result between the deviation and the first preset threshold, assign weights to the first voltage and the second voltage.

[0110] Specifically, the control unit will control the deviation. and The absolute value and the preset first threshold Compare the results. Dynamically assign weights based on the comparison results:

[0111] like and The absolute values ​​of all are less than or equal to Both can be assigned similar weights.

[0112] If the absolute value of the deviation of one of the data is less than or equal to The other path is greater than If the data with a large deviation is judged to be more susceptible to interference, then the data with a smaller absolute deviation should be assigned a higher weight, and vice versa.

[0113] like and The absolute values ​​are all greater than However, since the two values ​​differ, weights are assigned based on how much they exceed the threshold, with the larger the deviation, the lower the weight. One specific implementation can be based on the formula:

[0114] ;

[0115] ;

[0116] in, The first voltage, For the second voltage, This is the jump value corresponding to the first voltage. This is the jump value corresponding to the second voltage. This is the first preset threshold.

[0117] Step S604: The first voltage and the second voltage are weighted according to the assigned weights to obtain the final voltage.

[0118] .

[0119] This embodiment introduces a dynamic moving average, allowing weight allocation to be based on the deviation of each voltage data point relative to the overall system. This enables adaptive data fusion even when two voltage data points exhibit similar trends but differ in their degree of interference, effectively suppressing noise interference and improving the accuracy of the voltage sampling algorithm.

[0120] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0121] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0122] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A battery management system with redundant data acquisition, characterized in that, The battery management system includes a first voltage acquisition unit, a second voltage acquisition unit, and a control unit. The first voltage acquisition unit and the second voltage acquisition unit are respectively connected to a battery pack, and the battery pack includes multiple battery cells. The control unit is connected to both the first voltage acquisition unit and the second voltage acquisition unit. The first voltage acquisition unit is used to acquire the first voltage of the target battery cell; The second voltage acquisition unit is used to acquire the second voltage of the target battery cell; The control unit is used to receive the first voltage and the second voltage, and perform a weighted fusion calculation based on the deviation between the two to obtain the final voltage value of the target cell.

2. The system according to claim 1, characterized in that, The second voltage acquisition unit includes a resistor divider network and a multiplexing circuit; the multiplexing circuit is connected to the resistor divider network; the first voltage acquisition unit is connected to the second voltage acquisition unit. The resistor voltage divider network is connected to the battery pack and is used to divide the voltage of the battery pack and form multiple voltage divider nodes; The first voltage acquisition unit sends a selection command to the multiplexing circuit to control the multiplexing circuit to select the voltage divider node corresponding to the target cell and acquire the voltage value of the circuit being conducted to obtain the second voltage.

3. The system according to claim 2, characterized in that, The control unit is configured to: The second voltage of the target cell is obtained by the difference between the first total voltage corresponding to the first voltage divider node selected at the current time and the second total voltage corresponding to the adjacent voltage divider node selected at the previous acquisition time.

4. The system according to claim 1, characterized in that, The first voltage acquisition unit includes a first analog front-end chip, and the second voltage acquisition unit includes a second analog front-end chip; the first analog front-end chip and the second analog front-end chip acquire voltage from the same cell through different voltage acquisition channels.

5. The system according to any one of claims 1 to 4, characterized in that, When the battery pack is in a charging or discharging state, the control unit is configured to: When either the first voltage or the second voltage experiences a jump that is opposite to the voltage change trend of the other cells, while the other voltage has the same change trend as the other cells, the voltage with the same change trend is taken as the final voltage.

6. The system according to claim 5, characterized in that, The control unit is also configured to: When both the first voltage and the second voltage change in the same direction, the moving average of the voltage change of all cells in the battery pack at the current moment is calculated. The deviation of the voltage change value of the first voltage and the second voltage from the moving average is calculated respectively. Based on the comparison result of the deviation with a first preset threshold, the first voltage and the second voltage are assigned weights and weighted calculation is performed to obtain the final voltage.

7. The system according to claim 6, characterized in that, The formula for weighted fusion calculation of the first voltage and the second voltage is as follows: ； in, For the final voltage, The first voltage, The second voltage, This is the jump value corresponding to the first voltage. This is the jump value corresponding to the second voltage. The first preset threshold is used.

8. The system according to any one of claims 1 to 4, characterized in that, When the battery pack is in a static state, the control unit is also configured to: Determine whether the first voltage and the second voltage have undergone a jump in amplitude exceeding a second preset threshold relative to their historical values, and take the collected voltage whose jump amplitude does not exceed the second preset threshold as the final voltage.

9. A battery management method for redundant data acquisition, used in the system as described in any one of claims 1-8, characterized in that, The method includes: Obtain the first and second voltages of the target cell in the battery pack; Calculate the deviation between the first voltage and the second voltage; The final voltage of the target battery cell is obtained by performing a weighted fusion calculation based on the deviation.

10. The method according to claim 9, characterized in that, The weighted fusion calculation based on the deviation to obtain the final voltage of the target battery cell includes: When both the first voltage and the second voltage change in the same direction, calculate the moving average of the voltage changes of all cells in the battery pack at the current moment. Calculate the deviations of the jump values ​​of the first voltage and the second voltage relative to the moving average value, respectively; Based on the comparison result between the deviation and the first preset threshold, weights are assigned to the first voltage and the second voltage; The first voltage and the second voltage are weighted according to the assigned weights to obtain the final voltage.

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