A synchronous measurement system and method for measuring the resistance of a battery and the resistance of a connecting strip

Abstract

The application relates to the technical field of measuring electric variables, and particularly discloses a storage battery internal resistance and connecting strip resistance synchronous measurement system and method, which comprises the following steps: a storage battery and a connecting strip are combined to form a battery unit, and synchronous measurement of voltage differences at two ends of the connecting strip to which each battery unit belongs is dynamically triggered in combination with total discharge current, so that real-time and accurate analysis of the connecting strip resistance is realized, a complete broken line graph and a normal broken line graph are generated based on the resistance value to form coincidence comparison, and a closed-loop logic from dynamic trigger measurement to resistance accurate calculation to strategy optimization feedback is formed. The storage battery internal resistance and connecting strip resistance synchronous measurement system can not only guarantee the timeliness and accuracy of the connecting strip resistance measurement, reduce the influence of interference factors through the synchronous measurement strategy, but also continuously improve the system measurement stability through sampling single amplifier analysis and strategy initialization optimization, and provide reliable resistance data support for safe operation and state evaluation of the storage battery group.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measuring electrical variables, in particular to a storage battery internal resistance and connecting strip resistance synchronous measurement system and method. BACKGROUND

[0002] Currently, there are various technologies for measuring the internal resistance of storage batteries and the internal resistance of their connecting strips, which have been put into practical application. Common measurement systems generally include a storage battery, a load circuit, a synchronous acquisition circuit, a controller, and the like. The load circuit is connected to the electrodes of the storage battery by means of test lines to obtain the power required for work. The synchronous acquisition circuit is also electrically connected to the storage battery by means of test lines, and thus can acquire the current data and voltage data inside the storage battery. The controller is connected to the synchronous acquisition circuit to effectively control the working state of the synchronous acquisition circuit. In the actual measurement process, when the load circuit is connected to the storage battery, the storage battery provides working current for it. At this time, the synchronous acquisition circuit starts to acquire relevant data, and finally the controller calculates the internal resistance of the storage battery and the resistance of the connecting strip according to the acquired current and voltage data using algorithms such as Ohm's law.

[0003] For example, the line connection method for measuring the internal resistance of a storage battery disclosed in Chinese Patent No. CN102981057B adopts power lines to connect the positive and negative poles of the storage battery in parallel with a voltmeter to obtain voltage sampling values, adopts power lines to connect the positive pole of the storage battery through the negative pole of the first storage battery to the first interface of the load resistance, and adopts power lines to connect the negative pole of the storage battery through the positive pole of the second storage battery to the second interface of the load resistance to perform constant-current discharge of the storage battery. Using the above-mentioned line, the internal resistance value of the storage battery can also be calculated according to Ohm's law.

[0004] For example, the single storage battery internal resistance measurement circuit and method disclosed in Chinese Patent No. CN107797074A includes an MCU microcontroller unit, a differential amplification circuit, a switch driving circuit, a band-pass filter amplification circuit, a load resistance, a current sampling resistance, and a discharge switch. The load resistance, the current sampling resistance, and the discharge switch are connected in series across the two ends of the measured single battery to form a direct-current pulse discharge circuit. The input end of the band-pass filter amplification circuit is connected across the two ends of the measured single battery, and the output end is connected to the analog-to-digital conversion port ADC2 of the MCU microcontroller unit. The input end of the differential amplification circuit is connected across the two ends of the current sampling resistance, and the output end is connected to the analog-to-digital conversion port ADC1 of the MCU microcontroller unit. The input end of the switch driving circuit is connected to the MCU microcontroller unit, and the output end is connected to the discharge switch.

[0005] The above technology has at least the following technical problems: the operational amplifier itself is unstable in voltage, which weakens the anti-interference ability of the amplifier and makes it extremely fragile; whether it is inherent noise inside the circuit or external environmental electromagnetic noise, it is extremely easy to be captured and significantly amplified by the abnormal amplifier, causing the collected data to jump or drift. Since the resistance value is calculated from the amplified voltage and current data, distorted collected data eventually leads to a serious deviation of the calculated resistance value from the true value, making it completely unreliable. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application provides a storage battery internal resistance and connecting strip resistance synchronous measurement system and method, which can effectively solve the problems involved in the above background art.

[0007] To achieve the above object, the present application is realized by the following technical scheme: the present application provides a storage battery internal resistance and connecting strip resistance synchronous measurement system in the first aspect, comprising: a voltage difference measurement module, for connecting a plurality of storage batteries through a plurality of connecting strips to form a battery pack, wherein the adjacent two storage batteries and the corresponding connecting strips are marked as a battery unit, the total discharge current of the battery pack is collected in real time, the BMS host determines whether to issue a connecting strip internal resistance measurement signal, if yes, the voltage difference between the two ends of the connecting strip to which each battery unit belongs is measured by a synchronous measurement strategy, otherwise, the total discharge current of the battery pack is continuously collected; a sampling single-body amplifier adjustment module, for analyzing the resistance value of the connecting strip to which each battery unit belongs based on the voltage difference between the two ends of the connecting strip, and determining whether to analyze the sampling single-body amplifier of each battery unit; an initialization synchronous measurement module, for generating the complete resistance value fold line and the normal resistance value fold line corresponding to each battery unit based on the resistance value of the connecting strip to which each battery unit belongs collected, and performing coincidence comparison, so as to determine whether to reinitialize the synchronous measurement strategy.

[0008] The second aspect of the present application provides a method for synchronously measuring the internal resistance of a battery and the resistance of a connecting strip, comprising the following steps: step one, a plurality of batteries are connected by a plurality of connecting strips to form a battery pack, wherein two adjacent batteries and the corresponding connecting strip are marked as a battery unit, the total discharge current of the battery pack is collected in real time, and the BMS host determines whether to issue a measurement signal for the internal resistance of the connecting strip; if the determination is yes, the voltage difference between the two ends of the connecting strip to which each battery unit belongs is measured by a synchronous measurement strategy; otherwise, the total discharge current of the battery pack is continuously collected; step two, based on the voltage difference between the two ends of the connecting strip to which each battery unit belongs, the resistance value of the connecting strip to which each battery unit belongs is analyzed, and it is determined whether to analyze the sampling single amplifier of each battery unit; step three, based on the resistance value of the connecting strip to which each battery unit belongs collected, a complete resistance value fold line graph and a normal resistance value fold line graph corresponding to each battery unit are generated, and a coincidence comparison is performed to determine whether to re-initialize the synchronous measurement strategy.

[0009] Compared with the prior art, the embodiments of the present application have at least the following advantages or beneficial effects:

[0010] (1) The present application provides a system and method for synchronously measuring the internal resistance of a battery and the resistance of a connecting strip, which combines the total discharge current to dynamically trigger the synchronous measurement of the voltage difference between the two ends of the connecting strip to which each battery unit belongs. This not only realizes real-time and accurate analysis of the resistance of the connecting strip, but also forms a closed-loop logic from dynamic triggering measurement to accurate calculation of resistance to strategy optimization feedback based on the coincidence comparison of the complete fold line graph and the normal fold line graph generated based on the resistance value. This not only ensures the timeliness and accuracy of the resistance measurement of the connecting strip, but also reduces the influence of interference factors through the synchronous measurement strategy, and continuously improves the measurement stability of the system through the analysis of the sampling single amplifier and the optimization of the strategy initialization, providing reliable resistance data support for the safe operation and state evaluation of the battery pack.

[0011] (2) By dividing the battery pack into standardized battery units and monitoring the total current in real time, a clear object and trigger reference is provided for synchronous measurement; the BMS host intelligently determines the measurement opportunity according to the working conditions, issues instructions only when necessary, and instantaneously collects the voltage difference between the two ends of the connecting strip to which each battery unit belongs with the help of the synchronous strategy, effectively avoiding the problem of out-of-sync data caused by time delay in traditional sequential measurement, and laying a reliable foundation for subsequent accurate calculation of the resistance of the connecting strip.

[0012] (3) Based on the synchronous acquisition of voltage data, the resistance value of each connecting strip is quickly and accurately calculated by using Ohm's law, realizing the quantitative diagnosis of the electrical connection state; the system not only analyzes the resistance in isolation, but also further intelligently judges whether the front-end sampling unit needs to be diagnosed, thereby effectively distinguishing whether the connecting strip itself is abnormal or the measurement system is faulty, greatly improving the reliability of the entire internal resistance and connecting strip resistance synchronous measurement system and the accuracy of fault positioning.

[0013] (4) The method combining visualization and trend analysis is adopted, the actual and normal resistance value line chart is generated and compared, the state of the connecting strip is realized, the system can automatically determine whether to re-initialize the measurement strategy based on the graphical deviation, not only effectively avoiding the long-term error caused by the drift or fault of the measurement system itself, but also forming a complete measurement, diagnosis and calibration closed-loop management. BRIEF DESCRIPTION OF DRAWINGS

[0014] The application is further illustrated by the drawings, but the embodiments in the drawings do not constitute any limitation on the application, and other drawings can be obtained by the ordinary skilled in the art without creative labor on the basis of the following drawings.

[0015] Figure 1 It is a system module connection diagram of the application.

[0016] Figure 2 It is a method step flow diagram of the application.

[0017] Figure 3 It is a flow chart for judging the total discharge current of the application.

[0018] Figure 4 It is a flow chart for judging whether to optimize the sampling single amplifier corresponding to the connecting strip to which each abnormal battery unit belongs of the application.

[0019] Figure 5 It is a flow chart for judging whether to perform deep adjustment on the sampling single amplifier corresponding to the connecting strip to which each abnormal battery unit belongs of the application.

[0020] Figure 6 It is a flow chart for judging whether to analyze the sampling single amplifier of each battery unit of the application.

[0021] Figure 7 It is a flow chart for judging whether to optimize the sampling single amplifier corresponding to the connecting strip to which each battery unit to be optimized belongs of the application.

[0022] Figure 8 It is a flow chart for judging whether to perform deep optimization on the sampling single amplifier corresponding to the connecting strip to which each optimized battery unit belongs of the application.

[0023] Figure 9 Flow chart for initialization synchronization measurement module of the present application.

[0024] Figure 10 Connection diagram of battery internal resistance and connecting strip of the present application. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0026] With reference to Figure 1 , the system module connection diagram of the present application shows that the first aspect of the present application provides a battery internal resistance and connecting strip resistance synchronization measurement system, comprising: a voltage difference measurement module, a sampling single cell amplifier adjustment module, an initialization synchronization measurement module and a database.

[0027] The voltage difference measurement module is connected with the sampling single cell amplifier adjustment module, the sampling single cell amplifier adjustment module is connected with the initialization synchronization measurement module, the voltage difference measurement module is connected with the initialization synchronization measurement module, and the voltage difference measurement module, the sampling single cell amplifier adjustment module and the initialization synchronization measurement module are all connected with the database.

[0028] The database is used for storing parameters related to the battery internal resistance and connecting strip resistance synchronization measurement system and method.

[0029] Figure 3 The flow chart for judging the total discharge current of the present application, the BMS host collects the total discharge current of the battery pack in real time; if the total discharge current is not greater than the total discharge current threshold, the total discharge current is continuously collected; if the total discharge current is greater than the total discharge current threshold, the voltage difference between the two ends of the connecting strip to which each battery cell belongs is measured by a synchronization measurement detection technology. Then each battery cell is traversed, and it is judged whether the voltage difference between the two ends of the connecting strip to which it belongs is within the allowed voltage range: if the voltage difference between the two ends of the connecting strip to which it belongs is within the allowed voltage range, the sampling single cell amplifier corresponding to the connecting strip is not optimized; if the voltage difference between the two ends of the connecting strip to which it belongs is not within the allowed voltage range, the battery cell is marked as an abnormal battery cell. Figure 4For the flowchart of the application for judging whether to optimize the sampling single-body amplifier corresponding to the connection strip to which each battery unit belongs, if the voltage difference is greater than the maximum value of the allowed voltage range, the amplification coefficient is reduced based on the voltage difference; if the voltage difference at both ends of the connection strip belonging to it is less than the minimum value of the allowed voltage range, the amplification coefficient is increased based on the voltage difference. After adjustment, the connection strip voltage difference of the abnormal unit is synchronously measured to obtain the voltage difference at both ends of the connection strip belonging to each abnormal battery unit after adjustment; finally, it is judged whether to perform deep adjustment on the sampling single-body amplifier corresponding to the connection strip belonging to each abnormal battery unit.

[0030] Figure 5 For the flowchart of the application for judging whether to perform deep adjustment on the sampling single-body amplifier corresponding to the connection strip belonging to each abnormal battery unit, if deep adjustment is needed, the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after adjustment is obtained; each abnormal battery unit is traversed to judge whether the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after adjustment is within the allowed voltage range: if the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after adjustment is within the allowed voltage range, no deep adjustment is performed, and the unit processing is marked as completed; if the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after adjustment is not within the allowed voltage range, deep adjustment is performed on the unit, and the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after deep adjustment is obtained. Then it is judged whether the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after deep adjustment is within the allowed voltage range: if the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after deep adjustment is within the allowed voltage range, it means that the adjustment is successful, and the corresponding resistance value is calculated; if the voltage difference at both ends of the connection strip belonging to the abnormal battery unit after deep adjustment is not within the allowed voltage range, a voltage difference warning is triggered.

[0031] Specifically, the BMS host judges whether to issue a measurement connection strip resistance signal, and the specific judgment process is: the BMS host collects the total discharge current of the battery pack in real time through the current monitoring module, and continuously judges whether the total discharge current is greater than the total discharge current threshold.

[0032] If the total discharge current is less than or equal to the total discharge current threshold, the total discharge current of the battery pack is continuously collected.

[0033] If the total discharge current is greater than the total discharge current threshold, the voltage difference at both ends of the connection strip belonging to each battery unit is measured through a synchronous measurement strategy.

[0034] The voltage difference at both ends of the connection strip belonging to each battery unit is compared with the allowed voltage range to judge whether to optimize the sampling single-body amplifier corresponding to the connection strip belonging to each battery unit.

[0035] The total discharge current threshold is used to represent the minimum value of the total discharge current and is stored in the database.

[0036] By monitoring the total discharge current of the battery pack in real time and comparing it with the total discharge current threshold, the BMS host can intelligently trigger the synchronous voltage difference measurement of the connection strip resistance, avoiding measurement errors caused by insufficient signal-to-noise ratio in low current conditions, and ensuring that the resistance detection is only started when the current conditions meet the precise measurement requirements. This strategy not only improves the accuracy and reliability of the connection strip resistance measurement, but also optimizes the working time of the sampling single cell amplifier, significantly improving the overall monitoring efficiency of the system.

[0037] Specifically, whether to optimize the sampling single cell amplifier corresponding to the connection strip to which each battery cell belongs is determined by comparing the voltage difference between the two ends of the connection strip to which each battery cell belongs with the allowed voltage range. If the voltage difference between the two ends of the connection strip to which a certain battery cell belongs belongs to the allowed voltage range, it is determined that the sampling single cell amplifier corresponding to the connection strip to which the battery cell belongs is not optimized, and the resistance value of the connection strip to which the battery cell belongs is analyzed.

[0038] If the voltage difference between the two ends of the connection strip to which a certain battery cell belongs does not belong to the allowed voltage range, the battery cell is recorded as an abnormal battery cell, and it is determined that the sampling single cell amplifier corresponding to the connection strip to which the abnormal battery cell belongs is adjusted. The specific adjustment process is: under the condition that the voltage difference is greater than the maximum value of the allowed voltage range, the amplification coefficient of the sampling single cell amplifier is reduced based on the voltage difference, and under the condition that the voltage difference is less than the minimum value of the allowed voltage range, the amplification coefficient of the sampling single cell amplifier is increased based on the voltage difference.

[0039] After adjustment, the voltage difference between the two ends of the connection strip to which each abnormal battery cell belongs is measured again by the synchronous measurement strategy, the voltage difference between the two ends of the connection strip to which each abnormal battery cell belongs after adjustment is obtained, and it is determined whether to perform deep adjustment on the sampling single cell amplifier corresponding to the connection strip to which each abnormal battery cell belongs.

[0040] The allowed voltage range is used to represent the range of the voltage difference between the two ends of the connection strip to which a certain battery cell belongs, and is stored in the database.

[0041] Based on the voltage difference, the amplification coefficient of the sampling single cell amplifier is increased, and in the data, the voltage difference is divided into different gradients, each gradient corresponds to a different amplification coefficient increment value of the sampling single cell amplifier, and the existing amplification coefficient of the sampling single cell amplifier is added to the amplification coefficient increment value of the sampling single cell amplifier to obtain the amplification coefficient of the sampling single cell amplifier in the next step.

[0042] The voltage difference is divided into different gradients in the data, each gradient corresponds to a different reduction value of the amplification coefficient of the sampling single-body amplifier, and the existing amplification coefficient of the sampling single-body amplifier is reduced by the reduction value of the amplification coefficient of the sampling single-body amplifier to obtain the amplification coefficient of the next sampling single-body amplifier.

[0043] By dynamically adjusting the amplification coefficient of the sampling single-body amplifier, the abnormal situation of the voltage difference between the two ends of the connection strip can be accurately responded to, and closed-loop self-correction is realized: when the voltage difference exceeds the maximum value of the allowed range, the amplification coefficient is reduced in proportion to effectively suppress the over-collection of signals and avoid the virtual increase of the measurement value caused by the excessive gain of the amplifier; on the contrary, when the voltage difference is lower than the minimum value, the amplification coefficient is increased as needed to enhance the capture ability of weak signals and prevent effective signals from being overwhelmed by noise. This directional adjustment based on real-time voltage difference values not only significantly improves the accuracy and reliability of the battery unit voltage sampling data, but also avoids resource waste caused by global system adjustment through local targeted optimization, ultimately making the voltage measurement values between each battery unit more truly reflect the actual state, providing a more accurate data basis for the battery management system, and thus improving the safety and balanced control ability of the overall system.

[0044] By intelligently comparing the voltage difference between the two ends of the connection strip to which each battery unit belongs with the allowed voltage range, adaptive optimization of the sampling single-body amplifier is realized. The system can automatically identify abnormal battery units and dynamically adjust the amplification coefficient according to the voltage difference deviation direction, which not only real-time corrects the gain error of the measurement channel, but also provides a reliable data basis for subsequent deep adjustment. This method effectively guarantees the long-term stability and reliability of the synchronous measurement system under various working conditions.

[0045] Further, it is judged whether to perform deep adjustment on the sampling single-body amplifier corresponding to the connection strip to which each abnormal battery unit belongs. The specific judgment process is: if the voltage difference between the two ends of the connection strip to which the adjusted abnormal battery unit belongs belongs to the allowed voltage range, no deep adjustment is performed, and thus the resistance value of the connection strip to which the abnormal battery unit belongs is analyzed.

[0046] If the voltage difference between the two ends of the connection strip to which the adjusted abnormal battery unit belongs does not belong to the allowed voltage range, the sampling single-body amplifier corresponding to the connection strip to which the abnormal battery unit belongs is subjected to deep adjustment. The specific deep adjustment process is: based on the moving average window size of the voltage difference increase data processing algorithm.

[0047] The abnormal battery units after deep optimization are counted and marked as deep abnormal battery units. If the voltage difference between the two ends of the connection strip to which a deep abnormal battery unit belongs after deep optimization still does not belong to the allowed voltage range, a voltage difference warning is triggered at the two ends of the connection strip to which the deep abnormal battery unit belongs.

[0048] If the voltage difference between the two ends of the connection bar to which the deeply abnormal battery cell belongs belongs to the allowed voltage range, the resistance value of the connection bar to which the deeply abnormal battery cell belongs is analyzed.

[0049] When the system takes deep adjustment measures on the abnormal battery connection bar, the voltage difference between the two ends of the connection bar still cannot recover to the allowed voltage range. This indicates that the connection bar may have a physical failure that cannot be repaired by automatic calibration of the system. Triggering this early warning aims to send the highest level of emergency warning to the operation and maintenance personnel, prompting immediate manual on-site intervention to eliminate hidden dangers through physical inspection or replacement of the connection bar, so as to prevent the performance of the battery pack from being sharply reduced due to overheating of the connection point and uneven power transmission.

[0050] Based on the moving average window size of the voltage difference increase data processing algorithm, the voltage difference is divided into different gradients in the data, each gradient corresponds to a different moving average window size increment value of the data processing algorithm, and the existing moving average window size of the data processing algorithm is added to the moving average window size increment value of the data processing algorithm to obtain the moving average window size of the next data processing algorithm.

[0051] The data processing algorithm runs in the sampling single amplifier, and its core function is to perform real-time smoothing processing on the continuously sampled connection bar voltage difference raw data that may contain noise. It maintains a fixed moving average window size, continuously calculates the arithmetic mean of the latest batch of voltage difference data in the moving average window, and takes this average value as the filtered effective output value. When a new data point is collected, it is included in the window calculation, while the oldest data point in the window is discarded, thereby realizing the movement of the window. Increasing the window size means that the algorithm will average more historical data points, which can more effectively suppress random noise and transient interference, making the output curve smoother, but at the cost of slower system response to voltage changes. Conversely, reducing the window size will make the system respond faster, but the filtering effect will be weakened.

[0052] The core advantage of the deep adjustment strategy of increasing the moving average window size is to suppress noise and transient interference by enhancing data filtering effect. When the voltage difference between the two ends of the connection bar to which the adjusted abnormal battery cell belongs does not belong to the allowed voltage range, it indicates that the abnormality may be caused by random fluctuations or high-frequency noise rather than fixed deviation, and increasing the window size more effectively extracts the stable trend of the voltage signal, thereby significantly improving the reliability and stability of the measurement value. This optimization not only avoids introducing new errors due to excessive adjustment of hardware parameters, but also realizes effective suppression of deep abnormalities through flexible processing at the software algorithm level without changing the characteristics of the circuit.

[0053] Through multi-level judgment and progressive optimization strategy, fine processing of abnormal battery unit is realized. The system intelligently judges whether deep adjustment is needed based on the adjusted voltage difference result, avoiding unnecessary algorithm resource consumption; secondly, by increasing the moving average window size to smooth the data and suppress noise, the stability and accuracy of voltage difference measurement in complex interference environment are effectively improved; the units that are still out of limit after deep optimization trigger a warning, realizing accurate positioning and hierarchical warning of faults. This process significantly enhances the adaptive ability, robustness and reliability of the entire synchronous measurement system, providing strong protection for long-term accurate monitoring of battery connection strip resistance and internal resistance.

[0054] Figure 6 For the flowchart of the application for judging whether to analyze each battery unit sampling single amplifier, the resistance value of the connection strip to which each battery unit belongs is calculated according to Ohm's law; if the resistance value of the connection strip to which a certain battery unit belongs is within the normal resistance range, the resistance value is stored in the normal area of the database; if the resistance value of the connection strip to which a certain battery unit belongs is not within the normal resistance range, the resistance value is stored in the abnormal area of the database. Then, the abnormal parameters of the sampling single amplifier corresponding to the abnormal battery unit are analyzed; finally, it is judged whether to optimize the sampling single amplifier corresponding to the connection strip to which each battery unit belongs.

[0055] Figure 7 For the flowchart of the application for judging whether to optimize the sampling single amplifier corresponding to the connection strip to which each battery unit belongs, it is judged whether to optimize the sampling single amplifier corresponding to the connection strip to which each battery unit belongs; it is judged whether the sampling single amplifier corresponding to the connection strip to which the battery unit to be optimized belongs exists first comparison result: if the sampling single amplifier corresponding to the connection strip to which the battery unit to be optimized belongs exists first comparison result, resistance warning is triggered; if the sampling single amplifier corresponding to the connection strip to which the battery unit to be optimized belongs does not exist first comparison result, enter optimization process, judge the resistance value of the connection strip to which the battery unit to be optimized belongs. If the resistance value of the connection strip to which the battery unit to be optimized belongs is greater than the maximum value of the normal resistance range, the bias voltage of the sampling single amplifier is reduced based on the resistance value and the measurement abnormality index; if the resistance value of the connection strip to which the battery unit to be optimized belongs is less than the minimum value of the normal resistance range, the bias voltage of the sampling single amplifier is increased based on the resistance value and the measurement abnormality index. Then, all optimized sampling single amplifiers are counted, and the connection strip resistance value is measured again to obtain the resistance value of the optimized battery unit; finally, it is judged whether to perform deep optimization on the sampling single amplifier corresponding to the optimized unit.

[0056] Figure 8For the flowchart of the application for judging whether to perform deep optimization on the sampling single-cell amplifier corresponding to the connection strip to which the optimized battery cell belongs, it is judged whether to perform deep optimization on the sampling single-cell amplifier corresponding to the optimized cell; then it is judged whether there is a first comparison result for the sampling single-cell amplifier corresponding to the connection strip to which the optimized battery cell belongs: if there is a first comparison result for the sampling single-cell amplifier corresponding to the connection strip to which the optimized battery cell belongs, no deep optimization is performed; if there is no first comparison result for the sampling single-cell amplifier corresponding to the connection strip to which the optimized battery cell belongs, it is further judged whether the resistance value of the connection strip to which the optimized battery cell belongs belongs to the normal resistance value range: if the resistance value of the connection strip to which the optimized battery cell belongs is greater than the maximum value of the normal resistance value range, the cutoff frequency of the hardware low-pass filter is reduced based on the resistance value and the measurement abnormality index; if the resistance value of the connection strip to which the optimized battery cell belongs is less than the minimum value of the normal resistance value range, the cutoff frequency of the hardware low-pass filter is increased based on the resistance value and the measurement abnormality index. After completing the deep optimization, it is judged whether there is a first comparison result: if there is, a resistance warning is triggered; if there is not, an amplifier deep optimization warning is performed.

[0057] Specifically, it is judged whether to analyze the sampling single-cell amplifier of each battery cell, and the specific judgment process is: according to Ohm's law, the resistance value of the connection strip to which each battery cell belongs is calculated, and if the resistance value of the connection strip to which a certain battery cell belongs belongs to the normal resistance value range, the resistance value of the connection strip to which the battery cell belongs is stored in the database normal area.

[0058] According to Ohm's law, the resistance value of the connection strip to which each battery cell belongs is calculated, and the voltage value of the connection strip to which each battery cell belongs is processed by ratio with the total discharge current to calculate the resistance value of the connection strip to which each battery cell belongs.

[0059] If the resistance value of the connection strip to which a certain battery cell belongs does not belong to the normal resistance value range, the resistance value of the connection strip to which the battery cell belongs is stored in the database abnormal area, and the battery cell is marked as a to-be-optimized battery cell. The abnormal parameters of the sampling single-cell amplifier corresponding to the connection strip to which each to-be-optimized battery cell belongs are analyzed, and it is judged whether to optimize the sampling single-cell amplifier corresponding to the connection strip to which each to-be-optimized battery cell belongs.

[0060] The normal resistance value range is used to represent the range of the resistance value of the connection strip to which a certain battery cell belongs, and is stored in the database.

[0061] By intelligently comparing the resistance value with the normal resistance value range, the system can automatically screen out the battery unit to be optimized and store its data, which not only establishes a valuable historical database for trend analysis and fault prediction, but also provides a clear target and basis for subsequent amplifier parameter optimization. This method upgrades the traditional voltage monitoring to more essential resistance monitoring, greatly enhancing the diagnostic accuracy and depth of the battery internal resistance and connecting strip resistance synchronous measurement system, realizing the intelligent leap from monitoring phenomena to diagnosing roots, and providing core data support for the safe operation and precise maintenance of the battery pack.

[0062] Specifically, whether to optimize the sampling single-amplifier corresponding to the connecting strip to which the each battery unit to be optimized belongs is determined, and the specific determination process is as follows: if the sampling single-amplifier corresponding to the connecting strip to which the each battery unit to be optimized belongs has the first comparison result, resistance early warning is triggered.

[0063] The resistance early warning is triggered to prompt the staff in the form of sound and light, icon and message notification, so as to require the operation and maintenance personnel to intervene and manually check and preventively maintain the specified connecting strip.

[0064] If the sampling single-amplifier corresponding to the connecting strip to which the each battery unit to be optimized belongs does not have the first comparison result, optimization is performed, and the specific optimization process is as follows: if the resistance value of the connecting strip to which the each battery unit to be optimized belongs is greater than the maximum value of the normal resistance value range, the bias voltage of the sampling single-amplifier is reduced based on the resistance value of the connecting strip to which the each battery unit to be optimized belongs and the corresponding measurement abnormality index; if the resistance value of the connecting strip to which the each battery unit to be optimized belongs is less than the minimum value of the normal resistance value range, the bias voltage of the sampling single-amplifier is increased based on the resistance value of the connecting strip to which the each battery unit to be optimized belongs and the corresponding measurement abnormality index.

[0065] The first comparison result refers to that the measurement abnormality index is less than or equal to the measurement abnormality threshold.

[0066] The measurement abnormality threshold refers to the upper limit value of the measurement abnormality index.

[0067] The sampling single-amplifiers corresponding to the connecting strips to which the optimized battery units belong are counted, and the resistance values of the corresponding connecting strips are re-measured to obtain the resistance values of the connecting strips to which the optimized battery units belong, and whether to perform deep optimization on the sampling single-amplifiers corresponding to the connecting strips to which the optimized battery units belong is determined.

[0068] Based on the resistance value of the connection strip to which the battery cell to be optimized belongs and the measurement abnormality index, the bias voltage of the corresponding sampling cell amplifier is reduced, in the data, the resistance value of the connection strip to which the battery cell to be optimized belongs is divided into different gradients, each gradient corresponds to a different bias voltage reduction value of the sampling cell amplifier, the measurement abnormality index is divided into different gradients, each gradient corresponds to a different proportion coefficient, the bias voltage reduction value of the sampling cell amplifier is multiplied by the proportion coefficient to obtain the corrected bias voltage reduction value of the sampling cell amplifier, and the existing bias voltage of the sampling cell amplifier is subtracted from the corrected bias voltage reduction value of the sampling cell amplifier to obtain the bias voltage of the next sampling cell amplifier.

[0069] Based on the resistance value of the connection strip to which the battery cell to be optimized belongs and the measurement abnormality index, the bias voltage of the corresponding sampling cell amplifier is reduced, in the data, the resistance value of the connection strip to which the battery cell to be optimized belongs is divided into different gradients, each gradient corresponds to a different bias voltage reduction value of the sampling cell amplifier, the measurement abnormality index is divided into different gradients, each gradient corresponds to a different proportion coefficient, the bias voltage reduction value of the sampling cell amplifier is multiplied by the proportion coefficient to obtain the corrected bias voltage reduction value of the sampling cell amplifier, and the existing bias voltage of the sampling cell amplifier is subtracted from the corrected bias voltage reduction value of the sampling cell amplifier to obtain the bias voltage of the next sampling cell amplifier.

[0070] By dynamically adjusting the bias voltage of the sampling cell amplifier, the measurement deviation caused by the abnormal resistance of the connection strip can be effectively coped with: when the resistance value is not within the normal range, the system adjusts the bias voltage based on the cooperative analysis of the actual resistance value and the measurement abnormality index, thereby compensating for the signal acquisition error caused by the abnormal connection strip. This closed-loop regulation not only improves the accuracy and consistency of the sampling data, but also significantly suppresses the abnormal index fluctuations introduced by hardware bias during data fusion. Through real-time calibration at the hardware level, the probability of abnormal data generation is reduced, making the measurement abnormality index more stable within a reasonable threshold, thereby improving the reliability of the system in evaluating the state of the battery.

[0071] By introducing the key parameter of the measurement abnormality index, intelligent differentiation and accurate processing of the fault type of the sampling cell amplifier are realized. The system can effectively identify the measurement abnormality caused by the deviation of the amplifier itself and perform directional compensation accordingly, thereby correcting the root cause of the measurement error at the hardware level rather than simply relying on filtering. This optimization strategy based on resistance value and quantitative abnormality index greatly improves the measurement sensitivity and accuracy of small changes in the resistance of the connection strip, ensuring the long-term reliability of the synchronous measurement system data. At the same time, this process provides an accurate and reliable data foundation for subsequent deep optimization, and is the core guarantee for realizing high-precision and high-reliability monitoring of the connection state of the storage battery.

[0072] Further, it is judged whether to perform deep optimization on the sampling single cell amplifier corresponding to the connection strip to which the optimized battery cell belongs. The specific judgment process is: if there is a first comparison result for the sampling single cell amplifier corresponding to the connection strip to which the optimized battery cell belongs, no deep optimization is performed, and a resistance warning is triggered.

[0073] If there is no first comparison result for the sampling single cell amplifier corresponding to the connection strip to which the optimized battery cell belongs, deep optimization is performed. The specific deep optimization process is: if the resistance value of the connection strip to which the optimized battery cell belongs is greater than the maximum value of the normal resistance value range, the cutoff frequency of the hardware low-pass filter at the output end of the amplifier is reduced based on the resistance value of the connection strip to which the optimized battery cell belongs and the measurement abnormality index of the corresponding sampling single cell amplifier.

[0074] If the resistance value of the connection strip to which the optimized battery cell belongs is less than the minimum value of the normal resistance value range, the cutoff frequency of the hardware low-pass filter at the output end of the amplifier is increased based on the resistance value of the connection strip to which the optimized battery cell belongs and the measurement abnormality index of the corresponding sampling single cell amplifier. After deep optimization is completed, if there is still no first comparison result, an amplifier deep optimization warning is performed.

[0075] After deep optimization is completed, if there is still a first comparison result, a resistance warning is performed.

[0076] When the system confirms that the sampling single cell amplifier still cannot generate an effective first comparison result after completing deep optimization, the system will automatically trigger a warning process. This process usually includes: generating and recording a high-priority fault warning log, popping up a conspicuous warning message to the user through a human-computer interaction interface, which may be accompanied by sound and light prompts, and uploading this warning event to a remote monitoring center to notify maintenance personnel that manual intervention is needed to check whether the amplifier itself, the connection line or the sensor has a deeper hardware failure or uncontrollable external interference.

[0077] Then, based on the resistance value of the connection strip to which the optimized battery cell belongs and the measurement abnormality index of the corresponding sampling cell amplifier, the cut-off frequency of the hardware low-pass filter of the amplifier output end is increased, in the database, the resistance value of the connection strip to which the optimized battery cell belongs is divided into different gradients, each gradient corresponds to a different increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end, the measurement abnormality index of the corresponding sampling cell amplifier is divided into different gradients, each gradient corresponds to a different proportion coefficient, the increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end is multiplied by the proportion coefficient to obtain a corrected increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end, and the existing cut-off frequency of the hardware low-pass filter of the amplifier output end is added to the corrected increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end to obtain the cut-off frequency of the hardware low-pass filter of the amplifier output end in the next step.

[0078] Then, based on the resistance value of the connection strip to which the optimized battery cell belongs and the measurement abnormality index of the corresponding sampling cell amplifier, the cut-off frequency of the hardware low-pass filter of the amplifier output end is increased, in the database, the resistance value of the connection strip to which the optimized battery cell belongs is divided into different gradients, each gradient corresponds to a different increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end, the measurement abnormality index of the corresponding sampling cell amplifier is divided into different gradients, each gradient corresponds to a different proportion coefficient, the increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end is multiplied by the proportion coefficient to obtain a corrected increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end, and the existing cut-off frequency of the hardware low-pass filter of the amplifier output end is added to the corrected increase value of the cut-off frequency of the hardware low-pass filter of the amplifier output end to obtain the cut-off frequency of the hardware low-pass filter of the amplifier output end in the next step.

[0079] The adjustment mechanism can effectively filter out high-frequency noise and interference signals introduced by excessively high connection strip resistance by reducing the cut-off frequency of the hardware low-pass filter, thereby improving the stability and signal-to-noise ratio of the sampling data. Based on the cooperative decision of the resistance value and the measurement abnormality index, precise adaptive adjustment of the filtering strength is realized, and signal distortion caused by excessive filtering is avoided; the high-frequency fluctuations of abnormal data are suppressed from the hardware level, directly reducing the value of the measurement abnormality index, providing purer and more reliable input for subsequent data fusion, and thus comprehensively improving the accuracy and robustness of system state evaluation. If the abnormal index is still out of limit after deep optimization, a warning is triggered, indicating that there may be a deep fault beyond the hardware adjustment range.

[0080] Through the multi-stage progressive optimization strategy, the precise adjustment of the hardware parameters of the sampling system is realized. When the preliminary optimization fails to completely eliminate the error, the system can intelligently start deep optimization to further suppress noise and interference by dynamically adjusting the cutoff frequency of the hardware low-pass filter, thereby improving the signal quality at the circuit level rather than relying on software post-processing. This closed-loop control method based on resistance value and quantitative anomaly index significantly enhances the measurement accuracy of small internal resistance changes and the system's anti-interference ability in complex electromagnetic environments. The mechanism of triggering an early warning when the limit is exceeded after deep optimization provides the ultimate protection for the system, ensuring timely alarm for potential hardware failures, and greatly improving the reliability, adaptability and safety of the battery internal resistance and connecting strip resistance synchronous measurement system.

[0081] Specifically, the abnormal parameters of the sampling single amplifier are analyzed, including the noise spectral density of the sampling single amplifier, the slew rate of the sampling single amplifier, and the temperature drift of the sampling single amplifier.

[0082] The abnormal parameters of the sampling single amplifier need to be evaluated through systematic measurement. The noise spectral density of the sampling single amplifier can be measured by high-precision ADC to collect output data, and the noise voltage amplitude at different frequency points is measured under short-circuit input conditions, and then divided by the amplifier gain and normalized to 1 Hz bandwidth; the slew rate of the sampling single amplifier can be measured by inputting a large amplitude square wave signal, and the output waveform is captured by an oscilloscope to calculate the ratio of voltage change rate to time slope; the temperature drift of the sampling single amplifier is evaluated by using the SPICE model provided by the amplifier manufacturer, and the temperature scanning analysis is performed in the circuit simulation software. The changes of parameters such as offset voltage and bias current at different temperatures are directly read through simulation, and the temperature drift coefficient is calculated, which represents the sensitivity of the amplifier to temperature. The final temperature drift is the actual change value obtained by multiplying the temperature drift coefficient by a specific application temperature change range, thereby providing accurate data basis for error budgeting and performance design of circuit system.

[0083] The SPICE model is a precise mathematical model provided by the amplifier manufacturer for circuit simulation, which serves as a digital avatar of the chip in a virtual environment. When evaluating temperature drift, engineers use the model to perform temperature scanning analysis in simulation software. The model can automatically calculate parameter changes at different temperatures based on built-in physical laws, thereby efficiently and cost-effectively obtaining temperature drift coefficients and providing key data basis for circuit design.

[0084] The calculation of the measurement abnormality index of the sampling single amplifier is based on the proportional relationship between the noise spectral density of the sampling single amplifier and the defined noise spectral density, the proportional relationship between the defined pressure rate and the pressure rate of the sampling single amplifier, and the proportional relationship between the temperature drift of the sampling single amplifier and the defined temperature drift, and the specific process is: according to the influence degree of each proportional relationship on the measurement abnormality index of the sampling single amplifier, different measurement proportions are given, and then the measurement abnormality index of the sampling single amplifier is obtained.

[0085] The measurement abnormality index of the sampling single amplifier is used to quantify the measurement abnormality degree of the sampling single amplifier, and the specific expression is as follows:

[0086] ;

[0087] FYS is the measurement abnormality index of the sampling single amplifier, ZPD is the noise spectral density of the sampling single amplifier, YBL is the pressure rate of the sampling single amplifier, WPY is the temperature drift of the sampling single amplifier, ZPD_L is the defined noise spectral density in the database, YBL_L is the defined pressure rate in the database, WPY_L is the defined temperature drift in the database, A1 is the measurement proportion corresponding to the noise spectral density in the database, A2 is the measurement proportion corresponding to the pressure rate in the database, and A3 is the measurement proportion corresponding to the temperature drift in the database.

[0088] The defined noise spectral density is used to represent the upper limit value of the noise spectral density of the sampling single amplifier; the defined pressure rate is used to represent the lower limit value of the pressure rate of the sampling single amplifier; and the defined temperature drift is used to represent the upper limit value of the temperature drift of the sampling single amplifier.

[0089] The noise spectral density of the sampling single amplifier reflects the distribution characteristics of the internal noise of the amplifier, and its increase will cause the signal quality to decrease, thereby affecting the overall performance of the amplifier; the pressure rate of the sampling single amplifier represents the response ability of the amplifier to rapidly changing signals, and if the pressure rate is insufficient, distortion may be caused in high-frequency or transient signal processing, thereby indirectly aggravating the influence of noise; the temperature drift reflects the stability of the parameters of the amplifier with temperature change, and excessive temperature drift of the sampling single amplifier will cause the DC operating point to deviate, thereby affecting the consistency of the noise performance and the pressure rate. The three parameters jointly act on the measurement abnormality index of the sampling single amplifier: the noise spectral density of the sampling single amplifier reduces the signal-to-noise ratio by introducing additional noise, the pressure rate of the sampling single amplifier increases the risk of signal distortion by limiting the dynamic response ability, and the temperature drift of the sampling single amplifier causes parameter drift through environmental sensitivity, and the three parameters cooperatively amplify the abnormal effect, and finally the weighted summary is reflected on the measurement abnormality index, which comprehensively quantifies the abnormality degree of the amplifier.

[0090] The metric ratio corresponding to the noise spectral density of the sampling unit amplifier represents the proportional relationship between the noise spectral density of the sampling unit amplifier and the preset defined noise spectral density, and its influence on the measurement anomaly index of the sampling unit amplifier; the metric ratio corresponding to the slew rate of the sampling unit amplifier represents the proportional relationship between the preset defined slew rate and the slew rate of the sampling unit amplifier, and its influence on the measurement anomaly index of the sampling unit amplifier; the metric ratio corresponding to the temperature drift of the sampling unit amplifier represents the proportional relationship between the temperature drift of the sampling unit amplifier and the preset defined temperature drift, and its influence on the measurement anomaly index of the sampling unit amplifier, highlighting the diagnostic value of temperature stability in overall quantification.

[0091] The database stores preset benchmark parameters for evaluating measurement anomalies in the sampling unit amplifier, including defining noise spectral density, defining slew rate, and defining temperature drift. These parameters are dynamically correlated with the key performance indicators of the real-time sampling unit amplifier and the preset anomaly evaluation benchmarks through a structured parameter mapping table, forming a complete measurement anomaly evaluation system for the sampling unit amplifier. When it is necessary to calculate the measurement anomaly index of a specific sampling unit amplifier, the system extracts relevant parameters of the sampling unit amplifier, including its noise spectral density, slew rate, and temperature drift. Based on a preset rule base, these indicators are compared with the parameter mapping table in the database. Finally, the system dynamically outputs the defining noise spectral density, defining slew rate, and defining temperature drift applicable to the amplifier, along with the corresponding weighting coefficients. Among them, the A1, A2, and A3 measurement ratios serve as weighting coefficients, and their values ​​range from 0 to 1.

[0092] Figure 9 The flowchart for the initialization of the synchronous measurement module of this invention is as follows: First, the synchronous measurement module is initialized and enters the monitoring cycle. Then, a line graph of the normal resistance value of each battery cell is generated based on the normal area data in the database, and simultaneously, a line graph of the complete resistance value of each battery cell is generated based on the normal area and abnormal area data in the database. Next, the overlap comparison analysis of these two line graphs is performed to obtain the overlap degree of the resistance value line graph of the connecting strip to which a certain battery cell belongs. Then, it is determined whether the overlap degree of the resistance value line graph of the connecting strip to which the battery cell belongs is greater than or equal to the resistance value line graph overlap threshold: if it is greater than or equal to, the voltage difference of the connecting strip continues to be measured according to the current synchronous measurement strategy; if it is less than, the synchronous measurement strategy is re-initialized based on the resistance value line graph overlap degree, and the voltage difference of the connecting strip is measured according to the new strategy.

[0093] The overlap of resistance values ​​on the broken lines is obtained through data processing software (such as Matrix Lab).

[0094] Specifically, the determination of whether to re-initialize the synchronization measurement strategy is as follows: in the monitoring period, a normal resistance value polyline corresponding to each battery unit is generated based on the data in the normal region of the database, and a complete resistance value polyline corresponding to each battery unit is generated based on the data in the normal region of the database and the data in the abnormal region of the database.

[0095] The monitoring period refers to the time interval for the system to perform a complete integrity check and strategy evaluation.

[0096] The system first extracts two data sets from the database, including data in the normal region and data in the abnormal region; according to Ohm's law, the dynamic resistance value sequence of the connecting strip of each battery unit in the corresponding period is calculated using the two data sets respectively; finally, the calculated resistance value data points are connected with time as the horizontal axis and resistance value as the vertical axis, thereby drawing a curve containing the dynamic resistance value sequence of the connecting strip of the overall battery unit in the corresponding period, and separately drawing the dynamic resistance value sequence of the connecting strip of the battery unit in the corresponding period in the data in the normal region.

[0097] The data in the normal region and the data in the abnormal region, the data in the normal region includes resistance values belonging to the normal resistance range, and the data in the abnormal region includes resistance values not belonging to the normal resistance range.

[0098] By overlapping and comparing the normal resistance value polyline and the complete resistance value polyline, the resistance value polyline coincidence degree of the connecting strip to which each battery unit belongs is obtained, and is compared with the resistance value polyline coincidence threshold.

[0099] The overlapping comparison is made by Python to compare the overlapping proportion of the normal resistance value polyline and the complete resistance value polyline.

[0100] If the resistance value polyline coincidence degree of the connecting strip to which a certain battery unit belongs is greater than or equal to the resistance value polyline coincidence threshold, the voltage difference between the two ends of the connecting strip to which the battery unit belongs is measured according to the current synchronization measurement strategy.

[0101] If the resistance value polyline coincidence degree of the connecting strip to which a certain battery unit belongs is less than the resistance value polyline coincidence threshold, the synchronization measurement strategy is re-initialized based on the resistance value polyline coincidence degree, and the voltage difference between the two ends of the connecting strip to which the battery unit belongs is measured according to the re-initialized synchronization measurement strategy.

[0102] The synchronization measurement strategy is reinitialized based on the resistance value polyline coincidence degree, and the calculated coincidence index is matched with a preset mapping table to determine the synchronization measurement parameter combination to be adopted. The mapping table is pre-established based on experimental data or system experience, and clearly defines the optimal sampling frequency, synchronization clock compensation value and data alignment mode and other key parameters corresponding to different resistance value polyline coincidence degree intervals. Through this index and parameter mapping mechanism, the system can adaptively adjust the measurement strategy to ensure the accuracy and reliability of the voltage difference measurement when the resistance changes abnormally.

[0103] The reinitialized synchronization measurement strategy measures the voltage difference between the two ends of the connection strip to which the battery unit belongs, which is the initial synchronization measurement strategy for the next monitoring period.

[0104] The resistance value polyline coincidence threshold is used to represent the minimum value of the resistance value polyline coincidence degree of the connection strip to which the battery unit belongs, and is stored in the data.

[0105] Through intelligent analysis of historical data trends, self-feedback and dynamic optimization of the synchronization measurement strategy are realized. The system generates a polyline graph and performs coincidence degree analysis using normal and abnormal resistance values in the database, which can evaluate the applicability of the current measurement strategy for a specific battery unit from a macro perspective. If the coincidence degree is high, the strategy is effective and can be continued to save system resources; if the coincidence degree is low, the battery characteristics or noise environment have changed, and the measurement parameters need to be reinitialized based on the coincidence index. This data-driven strategy self-adjustment mechanism significantly improves the self-adaptive ability of the synchronization measurement system to the long-term performance evolution of the battery pack and the complex working environment.

[0106] Figure 10 For the connection diagram of the battery internal resistance and the connection strip of the present application, the sampling monomer is connected to the negative electrode of the first section battery, the positive electrode of the first section battery, and the negative electrode of the second section battery through three terminals; the positive electrode of the first section battery and the negative electrode of the second section battery are connected by a battery connection strip; the sampling monomer is connected to the host computer, and the BMS host computer collects the battery pack discharge current through the current monitoring module connected thereto. When the total discharge current is greater than a preset total discharge current threshold, the host computer sends a measurement connection strip resistance signal, the sampling monomer obtains the current voltage on the connection strip through an internal voltage sampling circuit, and sends the voltage to the BMS host computer. The BMS host computer calculates the resistance of the connection strip based on the current and voltage data, and also collects the internal resistance of the battery at the same time. When the internal resistance or connection strip resistance measurement is not performed, the BMS host computer is continuously in a voltage and current monitoring state.

[0107] Reference Figure 2The method step flowchart shown in the application, the second aspect of the application provides a battery resistance and connecting strip resistance synchronous measurement method, comprising: step one, for a plurality of batteries connected through a plurality of connecting strips, to form a battery pack, wherein, adjacent two batteries and the corresponding connecting strip are marked as a battery unit, the total discharge current of the battery pack is collected in real time, the BMS host judges whether to issue a measurement connecting strip resistance signal, if it is judged, the voltage difference between the two ends of the connecting strip to which each battery unit belongs is measured through a synchronous measurement strategy, otherwise, the total discharge current of the battery pack is continuously collected; step two, for analyzing the resistance value of the connecting strip to which each battery unit belongs based on the voltage difference between the two ends of the connecting strip, and judging whether to analyze the sampling single cell amplifier of each battery unit; step three, for generating the complete resistance value fold line chart and the normal resistance value fold line chart corresponding to each battery unit based on the resistance value of the connecting strip to which each battery unit belongs collected, and performing coincidence comparison, so as to determine whether to reinitialize the synchronous measurement strategy.

[0108] The above is only an example and description of the structure of the application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or use similar ways to replace, as long as the modifications or supplements do not deviate from the structure of the application or exceed the scope defined by the application, and should belong to the protection scope of the application.

Claims

1. A system for synchronously measuring the internal resistance of a battery and the resistance of a connecting strip, characterized in that, include: The voltage difference measurement module is used to connect several batteries through several connecting strips to form a battery pack. The module marks two adjacent batteries and their corresponding connecting strips as battery units. The total discharge current of the battery pack is collected in real time. The BMS host determines whether to send a signal to measure the internal resistance of the connecting strip. If it does, the voltage difference between the two ends of the connecting strip of each battery unit is measured through a synchronous measurement strategy. Otherwise, the total discharge current of the battery pack is collected. The sampling unit amplifier adjustment module is used to analyze the resistance value of the connecting strip of each battery unit based on the voltage difference between the two ends of the connecting strip of each battery unit, and to determine whether to analyze the sampling unit amplifier of each battery unit. The initialization synchronization measurement module is used to generate a complete resistance value line graph and a normal resistance value line graph for each battery cell based on the resistance values ​​of the connecting strips to which each battery cell belongs, and to compare the overlap values ​​to determine whether to re-initialize the synchronization measurement strategy. The determination of whether to analyze the sampling unit amplifier of each battery cell includes optimizing and adjusting the sampling unit amplifier corresponding to the connecting strip of each battery cell during synchronous measurement; The process of optimizing and adjusting the sampling unit amplifier corresponding to the connecting strip of each battery cell during synchronous measurement includes obtaining the voltage difference between the two ends of the connecting strip of each battery cell based on the synchronous measurement strategy. The voltage difference between the two ends of the connecting strip of each battery cell is compared with the allowable voltage range. If the voltage difference between the two ends of the connecting strip of a certain battery cell is within the allowable voltage range, it is determined that the sampling cell amplifier corresponding to the connecting strip of that battery cell will not be optimized. If the voltage difference between the two ends of the connecting strip to which a battery cell belongs is not within the allowable voltage range, the battery cell is recorded as an abnormal battery cell, and it is determined that the sampling unit amplifier corresponding to the connecting strip to which the abnormal battery cell belongs should be adjusted. The specific adjustment process is as follows: when the voltage difference is greater than the maximum value of the allowable voltage range, the amplification factor of the sampling unit amplifier is reduced based on the voltage difference; when the voltage difference is less than the minimum value of the allowable voltage range, the amplification factor of the sampling unit amplifier is increased based on the voltage difference. After adjustment, the voltage difference between the two ends of the connecting strip of each abnormal battery cell is measured again using the synchronous measurement strategy. The adjusted voltage difference between the two ends of the connecting strip of each abnormal battery cell is obtained, and it is determined whether to perform deep adjustment on the sampling cell amplifier corresponding to the connecting strip of each abnormal battery cell.

2. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 1, characterized in that: The BMS host determines whether to send a signal to measure the internal resistance of the connecting strip. The specific determination process is as follows: The BMS host collects the total discharge current of the battery pack in real time through the current monitoring module and continuously judges whether the total discharge current is greater than the total discharge current threshold. If the total discharge current is less than or equal to the total discharge current threshold, the total discharge current of the battery pack will continue to be collected. If the total discharge current is greater than the total discharge current threshold, the voltage difference between the two ends of the connecting strip of each battery cell is measured using a synchronous measurement strategy. Compare the voltage difference between the two ends of the connecting strip of each battery cell with the allowable voltage range to determine whether the sampling cell amplifier corresponding to the connecting strip of each battery cell needs to be optimized. The total discharge current threshold is used to characterize the minimum value of the total discharge current.

3. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 1, characterized in that: The specific process for determining whether to perform depth adjustment on the sampling cell amplifier corresponding to the connecting strip of each abnormal battery cell is as follows: If the voltage difference between the two ends of the connecting strip to which a certain abnormal battery cell belongs after adjustment is within the allowable voltage range, then no deep adjustment is performed, thereby analyzing the resistance value of the connecting strip to which the abnormal battery cell belongs. If the voltage difference between the two ends of the connecting strip of a certain abnormal battery cell after adjustment is not within the allowable voltage range, then the sampling cell amplifier corresponding to the connecting strip of the abnormal battery cell is deeply adjusted. The specific deep adjustment process is: increase the moving average window size of the data processing algorithm based on the voltage difference. The abnormal battery cells after deep optimization are identified and marked as deep abnormal battery cells. If the voltage difference between the two ends of the connecting strip of a certain deep abnormal battery cell is within the allowable voltage range after deep optimization, the resistance value of the connecting strip of that deep abnormal battery cell is analyzed. If the voltage difference between the two ends of the connecting strip of a certain deep-abnormal battery cell is still outside the allowable voltage range, a voltage difference warning will be triggered.

4. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 1, characterized in that: The specific process for determining whether to analyze the sampling amplifier of each battery cell is as follows: According to Ohm's law, the resistance value of the connecting strip to which each battery cell belongs is calculated. If the resistance value of the connecting strip to which a battery cell belongs is within the normal resistance value range, the resistance value of the connecting strip to which the battery cell belongs is stored in the normal area of ​​the database. If the resistance value of the connecting strip to which a certain battery cell belongs is not within the normal resistance value range, the resistance value of the connecting strip to which the battery cell belongs is stored in the abnormal area of ​​the database, and the battery cell is marked as a battery cell to be optimized. The abnormal parameters of the sampling unit amplifier corresponding to the connecting strip to which each battery cell to be optimized belongs are analyzed to determine whether the sampling unit amplifier corresponding to the connecting strip to which each battery cell to be optimized belongs should be optimized.

5. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 4, characterized in that: The abnormal parameters of the sampling unit amplifier are analyzed in detail as follows: Analyze the abnormal parameters of the sampling unit amplifier, including the noise spectral density, slew rate, and temperature drift of the sampling unit amplifier. The measurement anomaly index of the sampling unit amplifier is calculated based on the proportional relationship between the noise spectral density of the sampling unit amplifier and the boundary noise spectral density, the proportional relationship between the boundary slew rate and the slew rate of the sampling unit amplifier, and the proportional relationship between the temperature drift of the sampling unit amplifier and the boundary temperature drift. The specific process is as follows: different measurement ratios are assigned to the degree of influence of each proportional relationship on the measurement anomaly index of the sampling unit amplifier, and the results are summarized to finally obtain the measurement anomaly index of the sampling unit amplifier. The measurement anomaly index of the sampling unit amplifier is used to quantify the degree of measurement anomaly of the sampling unit amplifier.

6. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 5, characterized in that: The specific process for determining whether to optimize the sampling cell amplifier corresponding to the connecting strip of each battery cell to be optimized is as follows: If the sampling cell amplifier corresponding to the connecting strip of a battery cell to be optimized has a first comparison result, a resistance warning will be triggered. If the sampling unit amplifier corresponding to the connecting strip of a certain battery cell to be optimized does not have a first comparison result, then optimization is performed. The specific optimization process is as follows: if the resistance value of the connecting strip of the battery cell to be optimized is greater than the maximum value of the normal resistance value range, then the bias voltage of the sampling unit amplifier is reduced based on the resistance value of the connecting strip of the battery cell to be optimized and the corresponding measurement anomaly index. If the resistance value of the connecting strip to which the battery cell to be optimized belongs is less than the minimum value of the normal resistance value range, then the bias voltage of the sampling cell amplifier is increased based on the resistance value of the connecting strip to which the battery cell to be optimized belongs and the corresponding measurement anomaly index. The first comparison result refers to a measurement anomaly index that is less than or equal to the measurement anomaly threshold; The measurement anomaly threshold refers to the upper limit of the measurement anomaly index; The sampling unit amplifiers corresponding to the connecting strips of several battery cells to be optimized are identified, and the resistance values ​​of the corresponding connecting strips are remeasured to obtain the resistance values ​​of the connecting strips of each optimized battery cell. It is then determined whether to perform deep optimization on the sampling unit amplifiers corresponding to the connecting strips of each optimized battery cell.

7. A synchronous measurement system for battery internal resistance and connecting strip resistance according to claim 6, characterized in that: The specific process for determining whether to perform deep optimization on the sampling cell amplifiers corresponding to the connecting strips of each optimized battery cell is as follows: If the sampling cell amplifier corresponding to the connecting strip of an optimized battery cell has a first comparison result, then no deep optimization will be performed; If the sampling unit amplifier corresponding to the connecting strip of an optimized battery cell does not have a first comparison result, then deep optimization is performed. The specific deep optimization process is as follows: if the resistance value of the connecting strip of the optimized battery cell is greater than the maximum value of the normal resistance value range, then the cutoff frequency of the hardware low-pass filter at the amplifier output is reduced based on the resistance value of the connecting strip of the optimized battery cell and the measurement anomaly index of the corresponding sampling unit amplifier. If the resistance value of the connecting strip to which the optimized battery cell belongs is less than the minimum value of the normal resistance range, the cutoff frequency of the hardware low-pass filter at the amplifier output is increased based on the resistance value of the connecting strip to which the optimized battery cell belongs and the measurement anomaly index of the corresponding sampling single-cell amplifier. If the first comparison result is still not found after the deep optimization is completed, an amplifier deep optimization warning is issued.

8. The battery internal resistance and connecting strip resistance synchronous measurement system according to claim 1, characterized in that: The specific process for determining whether to reinitialize the synchronization measurement strategy is as follows: During the monitoring period, a line chart of normal resistance values ​​for each battery cell is generated based on data from the normal area of ​​the database, and a line chart of complete resistance values ​​for each battery cell is generated based on data from the normal area of ​​the database and data from the abnormal area of ​​the database. By comparing and analyzing the normal resistance value line graph and the complete resistance value line graph, the degree of overlap of the resistance value line graphs of each battery cell's connecting strip is obtained, and compared with the resistance value line graph overlap threshold. The resistance value breakpoint overlap threshold represents the lower limit of the resistance value breakpoint overlap degree. If the resistance value of a certain battery cell's connecting strip overlap is greater than or equal to the resistance value's connecting strip overlap threshold, then continue to measure the voltage difference between the two ends of the connecting strip to which the battery cell belongs according to the current synchronous measurement strategy. If the resistance value of a connecting strip to which a battery cell belongs has a line overlap degree less than the resistance value line overlap threshold, the synchronous measurement strategy is re-initialized based on the resistance value line overlap degree, and the voltage difference between the two ends of the connecting strip to which the battery cell belongs is measured according to the re-initialized synchronous measurement strategy.

9. A method for synchronously measuring the internal resistance of a battery and the resistance of a connecting strip, applied to the synchronous measurement system for the internal resistance of a battery and the resistance of a connecting strip as described in any one of claims 1-8, characterized in that, include: Step 1: Several batteries are connected by several connecting strips to form a battery pack. Adjacent batteries and their corresponding connecting strips are marked as battery units. The total discharge current of the battery pack is collected in real time. The BMS host determines whether to send a signal to measure the internal resistance of the connecting strip. If it does, the voltage difference between the two ends of the connecting strip of each battery unit is measured through a synchronous measurement strategy. Otherwise, the total discharge current of the battery pack is collected. Step 2: Based on the voltage difference between the two ends of the connecting strip of each battery cell, analyze the resistance value of the connecting strip of each battery cell, and determine whether to analyze the sampling single-cell amplifier of each battery cell. Step 3: Based on the collected resistance values ​​of the connecting strips to which each battery cell belongs, generate a complete resistance value line graph and a normal resistance value line graph for each battery cell, and perform overlap comparison to determine whether to reinitialize the synchronous measurement strategy.

Images