A load balancing new energy battery energy efficiency optimization system and method

Abstract

The present invention discloses a load balancing new energy battery energy efficiency optimization system and method, belonging to the field of battery energy efficiency optimization. It includes: based on the working state data of the battery pack, extracting single-cell deviation data for single-point data monitoring. If abnormal data is detected, abnormal data analysis is carried out. If the battery pack is abnormal, the state of charge data of the battery pack is calculated to determine whether the battery pack is load balanced; when it is determined that there is load imbalance in the battery pack, the SOC values of each single-cell battery are obtained to evaluate its load balance difference level, a load balancing strategy is formulated according to the load balance difference level, and the working state data of the battery pack, warning information and the driving state information of the vehicle are sent to the vehicle dashboard for display through wireless communication technology. It solves the problems of comprehensively and real-time monitoring the battery pack, accurately determining the load balance status of the battery pack, and adopting differential strategies to optimize the battery energy efficiency and extend the battery life according to the degree of load imbalance.

Description

Technical Field

[0001] The present invention relates to the field of battery energy efficiency optimization, and more particularly to a load-balanced new energy battery energy efficiency optimization system and method. Background Art

[0002] As a key power source for means of transportation such as electric two-wheelers and electric three-wheelers, new energy batteries are increasingly widely used. However, new energy batteries face many challenges in practical applications. On the one hand, there are differences in production processes and material properties among different battery monomers, resulting in extremely easy load imbalance in the battery pack during charging and discharging. For example, a certain monomer battery may bear more load during discharge due to its relatively high internal resistance, leading to premature depletion of power and affecting the performance and lifespan of the entire battery pack. On the other hand, the driving conditions of electric two-wheelers and three-wheelers are complex and variable. When frequently starting and stopping in urban congested sections, or encountering different road conditions such as climbing slopes and bumps on rural roads, and carrying different weights of goods, the battery load fluctuates greatly, further exacerbating the load imbalance problem. Load imbalance not only reduces the available capacity of the battery pack, but also causes overcharging and over-discharging of some batteries, shortening the battery lifespan and increasing the replacement cost. At the same time, the battery energy efficiency also needs to be improved urgently. Inefficient energy conversion means limited vehicle cruising range and cannot meet the growing travel and usage needs of users.

[0003] Chinese patent application with publication number CN114987233A discloses a charging and swapping control system and control method for low-speed electric vehicles. The charging and swapping control system includes: a first high-voltage control component; a second high-voltage control component; a battery main control module that controls the working states of the first high-voltage control component and the second high-voltage control component according to the first voltage of the first battery pack, the second voltage of the second battery pack, and the pre-charging voltage of the electrical load device. Although the prior art realizes small-current pre-charging between unbalanced battery packs during the swapping process to achieve consistent voltage platforms and eliminates potential safety hazards caused by the electric "sparking" phenomenon that may occur during the instant parallel connection of each battery pack when there is a large voltage difference. It still fails to solve the problems of comprehensively and real-time monitoring the working states of each monomer battery in the battery pack during charging and discharging, as well as the vehicle driving state information; accurately judging whether the battery pack is load-balanced, rather than only focusing on the voltage balance of the battery packs during swapping; and taking targeted strategies according to different degrees of imbalance to optimize the battery energy efficiency and extend the battery lifespan when the battery pack has a load imbalance. Therefore, in order to overcome these limitations, the present invention proposes a load-balanced new energy battery energy efficiency optimization system and method. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a load balancing new energy battery energy efficiency optimization system and method, which solves the problems of comprehensively and real-time monitoring the charging and discharging working states of single cells in a battery pack and the vehicle driving state; accurately determining the load balancing condition of the battery pack; and adopting differential strategies to optimize the battery energy efficiency and extend the battery life according to the degree of load imbalance.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A load balancing new energy battery energy efficiency optimization system includes a state monitoring module, a data analysis module, a load balancing module, and a communication display module;

[0007] The state monitoring module is used to collect the working state data of each single cell in the battery pack during charging and discharging, including voltage data, current data, and temperature data, and obtain the vehicle driving state information, including speed, acceleration, and load;

[0008] The data analysis module is used to extract single cell deviation data for single point data monitoring based on the working state data of the battery pack. If abnormal data is detected, abnormal data analysis is performed, and it is judged whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, the state of charge data of the battery pack is calculated to judge whether the battery pack is load balanced;

[0009] The load balancing module is used to, when it is determined that there is load imbalance in the battery pack, obtain the SOC values of each single cell to evaluate its load balancing difference level, and formulate load balancing strategies according to the load balancing difference level, including a simple balancing strategy, an active balancing strategy, and an abnormal warning strategy, to balance the load of the battery pack;

[0010] The communication display module is used to send the working state data of the battery pack, warning information, and the vehicle driving state information to the vehicle dashboard for display through wireless communication technology.

[0011] Specifically, the specific steps for judging whether the battery pack is load balanced include:

[0012] According to the working state data of each single cell in the battery pack collected, the single cell deviation data of the battery pack is extracted by calculating the extreme value difference of each working state data of the battery pack;

[0013] Configure a single cell deviation threshold, and based on the single cell deviation data of the battery pack, perform single point data monitoring. If there is single cell deviation data greater than the corresponding single cell deviation threshold, it is determined that the single point data is abnormal, and the current working state data is marked as abnormal data, otherwise no processing is performed;

[0014] If abnormal data is detected, perform abnormal data analysis, count the frequency of the abnormal data occurrence, and set a monitoring interval to measure the number of times of data collection for the monitoring work status.

[0015] Configure an equilibrium threshold. If the proportion of the number of times the abnormal data appears within the monitoring interval to the total number of collections is greater than the equilibrium threshold, determine that the battery pack is abnormal, and calculate the state of charge data of the battery pack. The state of charge data includes the SOC value and the SOC change rate; otherwise, obtain the duration and interval time of the abnormal data appearance within the monitoring interval.

[0016] Specifically, the specific steps for determining whether the battery pack is load-balanced further include:

[0017] Set a duration threshold and an interval threshold. If the duration of the abnormal data appearance within the monitoring interval is greater than the duration threshold, or the interval time of the abnormal data appearance is less than the interval threshold, determine that the battery pack is abnormal, and calculate the state of charge data of the battery pack; otherwise, do not perform any processing.

[0018] Set a load balance threshold, obtain the SOC change rate of each single battery of the battery pack in the representative interval. If the absolute value of the difference between the SOC change rates of two single batteries in the battery pack is greater than the load balance threshold, determine that the battery pack has load imbalance; otherwise, do not perform any processing.

[0019] Specifically, the specific steps for calculating the state of charge data of the battery pack include:

[0020] Obtain the current data of the battery pack collected within the monitoring interval, and process the collected current data using a median filtering algorithm to remove abnormal current values.

[0021] According to the ampere-hour integration method, based on the current data within the monitoring interval processed by the median filtering algorithm, calculate the SOC value of each single battery at each moment within the monitoring interval.

[0022] Configure SOC statistic thresholds, including the SOC range threshold and the SOC standard deviation threshold. According to the SOC values of each single battery within the monitoring interval, calculate the statistics of the battery pack SOC value, including the range and the standard deviation.

[0023] If the statistics of the battery pack SOC value within the monitoring interval are all less than the corresponding SOC statistic thresholds, set the SOC change rate to 0.

[0024] Otherwise, according to the statistics of the battery pack SOC value, set a sliding window, respectively obtain the range sum of the battery pack SOC value within the sliding window, select the sliding window as the representative interval according to the range sum, and calculate the SOC change rate of the SOC values of each single battery in the representative interval.

[0025] Specifically, the specific steps for formulating a load balancing strategy include:

[0026] When it is determined that there is a load imbalance in the battery pack, evaluate the load balancing difference level of the battery pack according to the SOC value of each single battery, and classify it into mild imbalance, moderate imbalance, and severe imbalance;

[0027] When the load balancing difference level of the battery pack is mild imbalance, adopt a simple balancing strategy to adjust the load of the battery pack;

[0028] When the load balancing difference level of the battery pack is moderate imbalance, adopt an active balancing strategy to adjust the load of the battery pack;

[0029] When the load balancing difference level of the battery pack is severe imbalance, adopt an abnormal warning strategy. If the battery pack is in the charging state, immediately cut off the charging power supply to prevent the charging process from continuing, and send a push notification to the user's mobile phone for load balancing warning to remind the user to repair the vehicle;

[0030] If the battery pack is in the discharging state, gradually reduce the discharging current of the battery pack, and perform a load balancing warning by flashing the indicator light on the vehicle dashboard to remind the user to stop using the vehicle and repair the vehicle.

[0031] Specifically, the simple balancing strategy specifically includes:

[0032] Obtain the SOC value of each single battery in the current battery pack and the average SOC value of the battery pack;

[0033] If the battery pack is in the charging state, configure a charging acceleration threshold and a charging slowdown threshold, and divide the single batteries of the battery pack into a charging acceleration group, a charging maintenance group, and a charging slowdown group according to the average SOC value of the battery pack;

[0034] Divide the single batteries with an SOC value less than the charging acceleration threshold into the charging acceleration group, increase the charging current, and accelerate the charging speed. Determine the increased charging current according to the difference between the SOC value of the single battery and the charging acceleration threshold;

[0035] Divide the single batteries with an SOC value greater than the charging slowdown threshold into the charging slowdown group, reduce the charging current, and slow down the charging process. Determine the slowed-down charging current according to the difference between the SOC value of the single battery and the charging slowdown threshold;

[0036] Divide the single batteries with an SOC value greater than or equal to the charging acceleration threshold and less than or equal to the charging slowdown threshold into the charging maintenance group, and keep the charging current unchanged;

[0037] If the battery pack is in a discharging state, configure a discharging acceleration threshold and a discharging deceleration threshold. According to the average value of the state of charge (SOC) of the battery pack, divide the individual cells of the battery pack into a discharging acceleration group, a discharging maintenance group, and a discharging deceleration group; adjust the discharging currents of the discharging acceleration group and the discharging deceleration group respectively.

[0038] Configure a stop threshold, monitor the load state of the battery pack after the charging and discharging currents with mild imbalance are adjusted, and obtain the SOC value of each individual cell of the battery pack in real time. When the range of the SOC values of the battery pack is less than the stop threshold, restore the charging and discharging currents of the individual cells of the battery pack.

[0039] Specifically, the specific steps of the active balancing strategy include:

[0040] Obtain the SOC value of each individual cell of the current battery pack and the average value of the SOC of the battery pack, and use the average value of the SOC of the battery pack as the preliminary balancing value.

[0041] Compare the SOC value of each individual cell with the preliminary balancing value. For the individual cells with SOC values higher than the preliminary balancing value, mark them as rich state; for the individual cells with SOC values lower than the preliminary balancing value, mark them as deficit state.

[0042] According to the SOC value of each individual cell and the preliminary balancing value, combined with the rated capacity of the individual cell, calculate the target transferred charge amount.

[0043] Obtain the charging and discharging currents of each individual cell of the current battery pack, combine the SOC value of each individual cell with the target transferred charge amount, formulate an energy transfer plan, generate energy transfer pairs, and perform energy transfer on the individual cells of the battery pack.

[0044] Configure a transfer threshold. When the energy transfer ends, count the total transferred charge amount of all energy transfer pairs, compare it with the target transferred charge amount, calculate the transfer deviation. If it is greater than the transfer threshold, recalculate the state of charge data of the battery pack and determine whether the battery pack is load balanced.

[0045] If the battery pack is load balanced, do not perform any operation. Otherwise, re - adopt the active balancing strategy and perform energy transfer on the battery pack again.

[0046] During the implementation of the active balancing strategy, set the parameter range of the working state data, and monitor the working state data of the battery pack in real time. If there is a working state data of an individual cell that exceeds its parameter range, stop the energy transfer operation and issue an energy transfer warning.

[0047] Specifically, the specific steps of formulating the energy transfer plan include:

[0048] For the single cells marked as rich state and shortage state respectively, sort them in descending order according to the SOC value of the single cells, and determine the preliminary energy transfer direction of the battery pack according to the sorting result, that is:

[0049] Determine that the preliminary energy transfer direction is that the single cell with the highest SOC value in the rich state transfers energy to the single cell with the lowest SOC value in the shortage state, and the single cell with the second highest SOC value in the rich state transfers energy to the single cell with the second lowest SOC value in the shortage state, and so on, forming a one-to-one energy transfer pair;

[0050] According to the charge and discharge current of each single cell of the battery pack, dynamically adjust the preliminary balance value as the target balance value;

[0051] During the energy transfer process, real-time monitor the SOC value of the single cells in each energy transfer pair. If there is a single cell in the energy transfer pair that reaches the target balance value, stop the energy transfer and output the transferred charge amount of the energy transfer pair;

[0052] And compare the SOC value of the other single cell in the energy transfer pair with the target balance value. If it is greater than the target balance value, update the energy transfer direction, that is: this single cell transfers energy to the single cell with the lowest SOC value in the shortage state, forming a new energy transfer pair; otherwise, do not perform any processing;

[0053] During the energy transfer process, if the SOC values of the single cells in the energy transfer pair are equal, stop the energy transfer. If the SOC value of the single cell is equal to the target balance value, do not perform any processing. If the SOC value of the single cell is greater than the target balance value, update the energy transfer direction, otherwise do not perform any processing.

[0054] Specifically, the specific steps for dynamically adjusting the preliminary balance value include:

[0055] Obtain the charge and discharge current values of each single cell of the battery pack, and calculate the change amount of the charge and discharge electric quantity of each single cell in combination with the current value acquisition interval;

[0056] According to the change amount of the charge and discharge electric quantity of the single cell, update the SOC value of each single cell, and recalculate the SOC average value of the battery pack as the target balance value.

[0057] Specifically, the specific steps for evaluating the load balance difference level of the battery pack include:

[0058] Obtain the SOC value of each single cell of the battery pack within the monitoring interval, and obtain the current stored charge amount of the battery pack based on the rated capacity of each single cell;

[0059] Configure the growth trend threshold, obtain the range of the SOC values of the battery pack within the monitoring interval, perform linear fitting, obtain the slope of the fitting curve. If it is greater than the growth trend threshold, it is determined that there is a growth trend in the range of the SOC values of the battery pack, and it is classified as severe imbalance.

[0060] Otherwise, if it is determined that there is no growth trend in the range of the SOC values of the battery pack, calculate the average value of the range of the SOC values of the battery pack within the monitoring interval. Set the first imbalance threshold, including the first lower imbalance threshold and the first upper imbalance threshold. Dynamically adjust the first imbalance threshold according to the current stored charge of the battery pack in combination with the rated total charge of the battery pack to obtain the second imbalance threshold after dynamic adjustment, including the second lower imbalance threshold and the second upper imbalance threshold.

[0061] If the average value of the range of the SOC values of the battery pack within the monitoring interval is greater than the second upper imbalance threshold, it is classified as severe imbalance; if the average value of the range of the SOC values of the battery pack within the monitoring interval is less than the second lower imbalance threshold, it is classified as mild imbalance; otherwise, it is classified as moderate imbalance.

[0062] A method for optimizing the energy efficiency of a load-balanced new energy battery includes the following steps:

[0063] Collect the working state data of each single battery in the battery pack during charging and discharging, including voltage data, current data, and temperature data, and obtain the driving state information of the vehicle, including speed, acceleration, and load.

[0064] Based on the working state data of the battery pack, extract single-cell deviation data for single-point data monitoring. If abnormal data is detected, perform abnormal data analysis, and determine whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, calculate the state of charge data of the battery pack to determine whether the battery pack is load-balanced.

[0065] When it is determined that the battery pack has load imbalance, obtain the SOC values of each single battery to evaluate its load balance difference level, and formulate a load balance strategy according to the load balance difference level, including a simple balancing strategy, an active balancing strategy, and an abnormal warning strategy, to balance the load of the battery pack.

[0066] Send the working state data of the battery pack, warning information, and the driving state information of the vehicle to the vehicle dashboard for display through wireless communication technology.

[0067] The beneficial effects of the present invention:

[0068] 1. By collecting the voltage, current, temperature data of individual batteries and the vehicle driving state information in real time, it provides a comprehensive basis for data analysis. The data analysis module extracts the individual deviation data from the working state data through complex algorithms, conducts detailed single-point data monitoring, accurately judges whether the battery pack is abnormal and whether the load is balanced, and timely detects potential problems of individual batteries inside the battery pack to avoid the deterioration of problems, thereby extending the overall service life of the battery.

[0069] 2. According to the evaluated load balance difference level, different strategies are implemented. When the imbalance is mild, the simple balancing strategy takes effect; when the imbalance is moderate, the active balancing strategy intervenes. During the energy transfer process, it is monitored and adjusted flexibly in real time to ensure the continuous optimization of the battery pack balance, and further improve the performance and service life of the battery pack.

[0070] 3. When the battery pack shows severe imbalance, the power supply is immediately cut off during charging to prevent serious safety hazards such as battery bulging and fire caused by overcharging; during discharging, the discharge current is gradually reduced to avoid permanent damage caused by over-discharging of individual batteries. At the same time, by sending push notifications to the user's mobile phone and flashing the indicator light on the vehicle dashboard, etc., the user is informed in a timely manner that the vehicle needs to be repaired to ensure the safety of the user's life and property. Description of the Drawings

[0071] Figure 1 It is a schematic structural diagram of an energy efficiency optimization system for a load-balanced new energy battery according to the present invention;

[0072] Figure 2 It is a flowchart of the specific steps for judging whether the battery pack is load-balanced according to the present invention;

[0073] Figure 3 It is a schematic diagram of formulating a load balance strategy according to the present invention;

[0074] Figure 4 It is a flowchart of the specific steps for evaluating the load balance difference level of the battery pack according to the present invention;

[0075] Figure 5 It is a flowchart of the specific steps for the simple balancing strategy according to the present invention;

[0076] Figure 6 It is a flowchart of the specific steps for the active balancing strategy according to the present invention;

[0077] Figure 7 It is a flowchart of a method for optimizing the energy efficiency of a load-balanced new energy battery according to the present invention. Detailed Embodiments

[0078] Example 1

[0079] Please refer to Figure 1, this embodiment introduces an energy efficiency optimization system for load-balanced new energy batteries, which includes a state monitoring module, a data analysis module, a load balancing module, and a communication display module;

[0080] The state monitoring module is used to collect the working state data of each single battery in the battery pack during charging and discharging, including voltage data, current data, and temperature data, and obtain the driving state information of the vehicle, including speed, acceleration, and load;

[0081] In this embodiment, through sensing technology, whether the vehicle is running or in a static state after the vehicle is turned off, the working state data of each single battery in the battery pack is collected in real time. The working state data includes voltage data, current data, and temperature data. Among them, the voltage data is used to capture the subtle changes in the battery voltage; the current data is used to reflect the battery charge and discharge current situation; the temperature data collection is used to monitor the abnormal fluctuations of the battery temperature, providing a reliable data basis for subsequent battery state analysis. Comprehensively obtain the driving state information of the vehicle, covering speed, acceleration, and load. Use a speed sensor to quickly respond to changes in vehicle speed; an acceleration sensor captures the acceleration changes of the vehicle during startup, acceleration, deceleration, braking, etc.; a load sensor is used to measure the vehicle load, thus providing a strong basis for judging the load situation of the battery under different driving conditions.

[0082] The data analysis module is used to extract single-cell deviation data for single-point data monitoring based on the working state data of the battery pack. If abnormal data is detected, abnormal data analysis is performed to determine whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, the state of charge data of the battery pack is calculated to determine whether the battery pack is load-balanced;

[0083] Please refer to Figure 2 , preferably, the specific steps for determining whether the battery pack is load-balanced include:

[0084] According to the working state data of each single battery in the battery pack collected during charging and discharging, by calculating the extreme difference of each working state data of the battery pack, single-cell deviation data of the battery pack is extracted. The single-cell deviation data includes: voltage deviation data, current deviation data, and temperature deviation data. The calculation method of the single-cell deviation data is as follows:

[0085] ;

[0086] Among them, is the single-cell deviation data of the th working state data of the battery pack collected at time , The value of is is the th working state data of the th single cell in the battery pack collected at time is the total number of single cells in the battery pack, is the maximum value function, is the minimum value function;

[0087] Configure the single cell deviation threshold, which includes: voltage deviation threshold, current deviation threshold and temperature deviation threshold. Based on the single cell deviation data of the battery pack, perform single point data monitoring. If there is single cell deviation data greater than the corresponding single cell deviation threshold, it is determined that the single point data is abnormal, and the current working state data is marked as abnormal data, otherwise no processing is performed; for example, set the voltage deviation threshold to 0.1V, the current deviation threshold to 0.5A, and the temperature deviation threshold to 0.5°C. When the calculated voltage deviation data is greater than 0.1V, the voltage data at that time is marked as abnormal data.

[0088] If abnormal data is detected, perform abnormal data analysis, further count the frequency of abnormal data occurrence, set a monitoring interval to measure the number of times of monitoring the acquisition of working state data. For example, set the monitoring interval to 100 acquisitions, and calculate the proportion of the number of times abnormal data appears in the monitoring interval to the total number of acquisitions;

[0089] Configure the balancing threshold. If the proportion of the number of times abnormal data appears in the monitoring interval to the total number of acquisitions is greater than the balancing threshold, it is determined that the battery pack is abnormal, and calculate the state of charge data of the battery pack, which includes the SOC value and the SOC change rate; otherwise, obtain the duration and interval time of abnormal data appearance in the monitoring interval; not only pay attention to the frequency, but also analyze the duration and interval time of abnormal data appearance. If abnormal data appears continuously or the interval time is short, it indicates that the problem of the battery pack is more serious; if abnormal data appears occasionally and the interval time is long, it may be caused by accidental factors and needs continuous observation.

[0090] Set the continuous threshold and the interval threshold. If the duration of abnormal data appearance in the monitoring interval is greater than the continuous threshold, or the interval time of abnormal data appearance is less than the interval threshold, it is determined that the battery pack is abnormal, and calculate the state of charge data of the battery pack, otherwise no processing is performed;

[0091] Preferably, the specific steps for calculating the state of charge data of the battery pack include:

[0092] Obtain the current data of the battery pack collected within the monitoring interval. Since the driving conditions of electric two-wheelers and three-wheelers are complex, the current fluctuates frequently and is vulnerable to electromagnetic interference. Therefore, the median filtering algorithm is used to process the collected current data to remove instantaneous abnormal current values. During moments such as vehicle startup, acceleration, and braking, the current will experience significant fluctuations. The median filtering smooths these fluctuations to ensure the accuracy of the data.

[0093] According to the ampere-hour integration method, based on the current data within the monitoring interval processed by the median filtering algorithm, calculate the SOC value of each single battery at each moment within the monitoring interval respectively.

[0094] Configure the SOC statistic thresholds, including the SOC range threshold and the SOC standard deviation threshold. According to the SOC values of each single battery within the monitoring interval, calculate the statistics of the battery pack's SOC value, including the range and the standard deviation.

[0095] If the statistics of the battery pack's SOC value within the monitoring interval are all less than the corresponding SOC statistic thresholds, set the SOC change rate to 0. If the statistics of the battery pack's SOC value within the monitoring interval are all less than the corresponding SOC statistic thresholds, it indicates that the difference in the state of charge between single batteries is small, and the battery pack can be considered to be in a relatively balanced state. At this time, set the SOC change rate to 0. If the range or the standard deviation exceeds a certain reasonable range, it means that the difference in the state of charge between single batteries is large, and there is a situation of unbalanced load.

[0096] Otherwise, according to the statistics of the battery pack's SOC value, set a sliding window, which can be set to 10% - 20% of the monitoring interval. Respectively obtain the sum of the ranges of the battery pack's SOC value within the sliding window. Select the sliding window as the representative interval according to the sum of the ranges, and calculate the SOC change rate of the SOC values of each single battery within the representative interval. By comparing the SOC change rates of different single batteries, the charging and discharging differences of each single battery within the battery pack can be analyzed more deeply, and further judge the degree and cause of the unbalanced load. If the SOC change rates of several single batteries are significantly higher than those of other batteries, it means that these batteries have a faster charging and discharging speed during this period and may bear a greater load.

[0097] Set the load balance threshold, obtain the SOC change rate of each single battery of the battery pack within the representative interval. If the absolute value of the difference between the SOC change rates of two single batteries in the battery pack is greater than the load balance threshold, it is determined that the battery pack has an unbalanced load. Otherwise, no processing is performed, that is, it is considered that the current battery pack is in a balanced state in terms of load distribution.

[0098] The load balancing module is used to obtain the SOC values of each single battery to evaluate the load balancing difference level when it is determined that there is load imbalance in the battery pack, and formulate a load balancing strategy according to the load balancing difference level, including a simple balancing strategy, an active balancing strategy and an abnormal warning strategy, so as to balance the state of charge of each single battery;

[0099] Please refer to Figure 3 , preferably, the specific steps for formulating the load balancing strategy include:

[0100] When it is determined that there is load imbalance in the battery pack, evaluate the load balancing difference level of the battery pack according to the SOC values of the single batteries, and divide it into mild imbalance, moderate imbalance and severe imbalance;

[0101] Please refer to Figure 4 , preferably, the specific steps for evaluating the load balancing difference level of the battery pack include:

[0102] Obtain the SOC value of each single battery in the battery pack within the monitoring interval, and based on the rated capacity of each single battery, obtain the current stored charge of the battery pack, that is:

[0103] ;

[0104] Among them, is the current stored charge of the battery pack, is the rated capacity of the th single battery in the battery pack, is the SOC value of the th single battery in the battery pack, is the total number of single batteries in the battery pack;

[0105] Configure a growth trend threshold, obtain the range of the SOC values of the battery pack within the monitoring interval, and perform linear fitting to obtain the slope of the fitting curve. If the slope of the fitting curve is greater than the growth trend threshold, it is determined that there is a growth trend in the range of the SOC values of the battery pack, and it is divided into severe imbalance; during the charging and discharging process of electric two-wheelers and three-wheelers, if the SOC range shows a growth trend, it means that the performance differences of the single batteries in the battery pack are continuously expanding, which will lead to problems such as unstable power and shortened cruising range during vehicle driving. Timely determination of severe imbalance can remind users and maintenance personnel to intervene and handle as early as possible to avoid further damage to the battery pack.

[0106] Otherwise, it is determined that there is no increasing trend in the range of the SOC values of the battery pack, and then the average value of the range of the SOC values of the battery pack within the monitoring interval is calculated. A first imbalance threshold is set, including a first lower imbalance threshold and a first upper imbalance threshold. The first lower imbalance threshold is used to define the boundary between mild imbalance and moderate imbalance, and the second upper imbalance threshold is used to distinguish between moderate imbalance and severe imbalance. According to the current stored charge amount of the battery pack, combined with the rated total charge amount of the battery pack, the first imbalance threshold is dynamically adjusted to obtain a dynamically adjusted second imbalance threshold, including a second lower imbalance threshold and a second upper imbalance threshold, that is:

[0107] ;

[0108] ;

[0109] Wherein, and are the dynamically adjusted second lower imbalance threshold and second upper imbalance threshold, and are the first lower imbalance threshold and first upper imbalance threshold, is the rated total charge amount of the battery pack, and are the lower percentage of the stored charge amount of the battery pack and the upper percentage of the stored charge amount of the battery pack, and are the minimum value and maximum value of the dynamically adjusted second lower imbalance threshold, and are the minimum value and maximum value of the dynamically adjusted second upper imbalance threshold, and are the maximum value function and minimum value function respectively; for the high state of charge interval, since the performance of the battery pack is relatively stable, in order to more strictly monitor the load balance situation, the first imbalance threshold is tightened. For the medium state of charge interval, the first imbalance threshold remains unchanged. For the low state of charge interval, considering the performance fluctuations caused by factors such as the increase in the internal resistance of the battery, the first imbalance threshold is relaxed;

[0110] If the average value of the range of the SOC values of the battery pack within the monitoring interval is greater than the second upper imbalance threshold, it is classified as severe imbalance; if the average value of the range of the SOC values of the battery pack within the monitoring interval is less than the second lower imbalance threshold, it is classified as mild imbalance; otherwise, it is classified as moderate imbalance.

[0111] When the load balance difference level of the battery pack is mild imbalance, a simple equalization strategy is adopted;

[0112] Please refer to Figure 5 Preferably, the specific steps of the simple equalization strategy include:

[0113] Obtain the SOC value of each single battery of the current battery pack and the SOC average value of the battery pack;

[0114] If the battery pack is in the charging state, configure the charging acceleration threshold and charging slowdown threshold, and divide the single cells of the battery pack into the charging acceleration group, charging maintenance group and charging slowdown group according to the average SOC of the battery pack; the charging acceleration threshold is set to the average SOC of the battery pack minus a fixed percentage, such as 5%, and the charging slowdown threshold is set to the average SOC of the battery pack plus a fixed percentage, such as 10%;

[0115] The single cells with SOC values ​​less than the charging acceleration threshold are divided into the charging acceleration group. The state of charge of these single cells is obviously lower than the average level of the battery group. The charging speed needs to be accelerated to achieve the balance of the battery group, increase its charging current, and speed up the charging speed. According to the difference between the single cell SOC value and the charging acceleration threshold, the increased charging current is determined, that is:

[0116] ;

[0117] in, Is the charging acceleration group The charging current of each single cell is increased. Is the charging acceleration group The original charging current of each single cell, The value range is , is the total number of cells in the charging acceleration group, is the charging acceleration threshold, Is the charging acceleration group The SOC value of each single battery, is a coefficient mapping function, an example ;

[0118] The single cells with SOC values ​​greater than the charge slowdown threshold are divided into the charge slowdown group. The state of charge of the single cell is significantly higher than the average level of the battery group. It is necessary to slow down the charging speed to avoid overcharging, reduce its charging current, and slow down the charging process. According to the difference between the single cell SOC value and the charge slowdown threshold, the charging current after slowdown is determined, that is:

[0119] ;

[0120] in, Is the charging slowdown group The charging current of each single cell is reduced. Is the charging slowdown group The original charging current of each single cell, is the charge slowdown threshold, Is the charging slowdown group The SOC value of each single battery, is a coefficient mapping function, exemplary ;

[0121] During the charging process, the simple balancing strategy can enable the single cells with lower state of charge (SOC) to quickly replenish their power, and prevent the single cells with higher SOC from overcharging, ensuring that the power of each single cell in the battery pack increases evenly. For electric two-wheelers and three-wheelers, it can improve the overall charging efficiency of the battery pack, reduce the charging time, and at the same time avoid affecting the battery life and safety due to overcharging of individual batteries. For example, in daily use, users can complete charging faster and don't have to worry about the battery being damaged due to overcharging, extending the service life of the battery pack and reducing the usage cost.

[0122] Classify the single cells with SOC values greater than or equal to the charging acceleration threshold and less than or equal to the charging deceleration threshold into the charging maintenance group, and keep the charging current unchanged;

[0123] Similarly, if the battery pack is in a discharging state, configure the discharging acceleration threshold and the discharging deceleration threshold. According to the average SOC of the battery pack, divide the single cells of the battery pack into a discharging acceleration group, a discharging maintenance group, and a discharging deceleration group; adjust the discharging currents of the discharging acceleration group and the discharging deceleration group respectively to achieve the balance of the battery pack;

[0124] Classify the single cells with SOC values less than the discharging deceleration threshold into the discharging deceleration group, reduce the discharging current, slow down the discharging speed, and determine the reduced discharging current according to the difference between the SOC value of the single cell and the discharging deceleration threshold;

[0125] Classify the single cells with SOC values greater than the discharging acceleration threshold into the discharging acceleration group, increase their discharging current, and determine the reduced discharging current according to the difference between the SOC value of the single cell and the discharging acceleration threshold;

[0126] Classify the single cells with SOC values greater than or equal to the discharging deceleration threshold and less than or equal to the discharging acceleration threshold into the discharging maintenance group, and keep the discharging current unchanged; During the discharging process, the simple balancing strategy can make the discharging depths of each single cell tend to be consistent, and prevent individual batteries from over-discharging. This is crucial for the stable driving of electric two-wheelers and three-wheelers, ensuring that the vehicle has a stable power output during driving and will not suddenly lose power or drive abnormally due to over-discharging of individual batteries. At the same time, by reasonably adjusting the discharging current, the discharging time of the battery pack can be extended and the endurance of the vehicle can be improved.

[0127] Configure a stop threshold, monitor the load state of the battery pack after the mild imbalance charge and discharge current adjustment, and obtain the SOC value of each single cell of the battery pack in real time. When the range of the SOC values of the battery pack is less than the stop threshold, restore the charge and discharge currents of the single cells of the battery pack.

[0128] Please refer to Figure 6 , when the battery pack load balance difference level is moderately unbalanced, an active equalization strategy is adopted. The specific steps of the active equalization strategy include:

[0129] Obtain the SOC value of each single cell in the current battery pack and the average SOC of the battery pack, and use the average SOC of the battery pack as the preliminary equalization value;

[0130] Compare the SOC value of each single cell with the preliminary equalization value. For single cells with an SOC value higher than the preliminary equalization value, mark them as rich; for single cells with an SOC value lower than the preliminary equalization value, mark them as scarce; record the status information of each single cell for subsequent analysis and processing.

[0131] According to the SOC value of each single cell and the preliminary equalization value, combined with the rated capacity of the single cell, calculate the target transferred charge amount, that is:

[0132] ;

[0133] Among them, is the target transferred charge amount, is the preliminary equalization value, is the th rated capacity of the single cell in the battery pack, is the th SOC value of the single cell in the battery pack, The value range of , is the total number of single cells in the battery pack; accurately calculating the target transferred charge amount provides a quantitative basis for formulating the energy transfer plan. During the use of electric two-wheelers and three-wheelers, the state of charge of the battery pack will change continuously. By accurately calculating the target charge amount, the energy transfer can be reasonably arranged to ensure the effective improvement of the balance of the battery pack.

[0134] Obtain the charge and discharge current of each single cell in the current battery pack, combine the SOC value of each single cell with the target transferred charge amount, formulate an energy transfer plan, generate energy transfer pairs, and perform energy transfer on the single cells of the battery pack;

[0135] Preferably, the specific steps for formulating the energy transfer plan include:

[0136] For the single cells marked as in the rich state and the poor state respectively, sort them in descending order according to the SOC value of the single cells. If there are single cells with the same SOC value, sort them again from left to right according to the installation position of the single cells. Determine the preliminary energy transfer direction of the battery pack according to the sorting result, that is: determine that the preliminary energy transfer direction is that the single cell with the highest SOC value in the rich state transfers energy to the single cell with the lowest SOC value in the poor state, and the single cell with the second highest SOC value in the rich state transfers energy to the single cell with the second lowest SOC value in the poor state, and so on, to form a one-to-one energy transfer pair; Exemplarily, a battery pack of an electric tricycle has a total of 8 single cells. After obtaining the SOC value of each single cell, the single cells in the rich state are marked as: single cell 3 (SOC = 0.8), single cell 5 (SOC = 0.78), single cell 7 (SOC = 0.78), single cell 9 (SOC = 0.75); The single cells in the poor state are: single cell 2 (SOC = 0.25), single cell 4 (SOC = 0.25), single cell 6 (SOC = 0.2), single cell 8 (SOC = 0.18); Sort the single cells in the rich state in descending order according to the SOC value. At this time, the SOC values of single cell 5 and single cell 7 are the same. According to the installation position of the single cells from left to right, assuming that single cell 5 is on the left of single cell 7, the sorting is single cell 3, single cell 5, single cell 7, single cell 9. For the single cells in the poor state, sort them in descending order according to the SOC value of the single cells. The SOC values of single cell 2 and single cell 4 are the same. According to the installation position from left to right, assuming that single cell 2 is on the left of single cell 4, the sorting is single cell 2, single cell 4, single cell 6, single cell 8. According to the sorting result, determine the preliminary energy transfer direction and form a one-to-one energy transfer pair: single cell 3 transfers energy to single cell 8, single cell 5 transfers energy to single cell 6, single cell 7 transfers energy to single cell 4, and single cell 9 transfers energy to single cell 2.

[0137] According to the charge and discharge current of each single cell of the battery pack, dynamically adjust the preliminary equalization value as the target equalization value. The specific steps for dynamically adjusting the preliminary equalization value include:

[0138] Obtain the charge and discharge current values of each single cell of the battery pack, and calculate the change in charge and discharge power of each single cell in combination with the current value acquisition interval;

[0139] According to the change in charge and discharge power of the single cell, update the SOC value of each single cell, and recalculate the SOC average value of the battery pack as the target equalization value.

[0140] During the energy transfer process, the SOC value of each single battery in the energy transfer pair is monitored in real time. If there is a single battery in the energy transfer pair that reaches the target equilibrium value, the energy transfer is stopped, the transferred charge amount of the energy transfer pair is output, and the SOC value of the other single battery in the energy transfer pair is compared with the target equilibrium value. If it is greater than the target equilibrium value, the energy transfer direction is updated, that is: this single battery transfers energy to the single battery with the lowest SOC value in the shortage state to form a new energy transfer pair. If there are single batteries with the same SOC value, the single batteries are selected according to the installation position of the single batteries from left to right to form a new energy transfer pair; otherwise, no processing is performed; monitoring and flexibly adjusting the energy transfer process in real time can ensure that the effect of energy transfer reaches the best. Timely stopping the energy transfer pair that reaches the target equilibrium value can avoid over-equilibration, and at the same time continuously adjust the single batteries that have not reached equilibrium to ensure the continuous optimization of the balance of the battery pack.

[0141] If the SOC values of the single batteries in the energy transfer pair are equal, the energy transfer is stopped. If the SOC value of the single battery is equal to the target equilibrium value, no processing is performed. If the SOC value of the single battery is greater than the target equilibrium value, the energy transfer direction is updated, otherwise no processing is performed; Exemplarily, after dynamically updating all single batteries according to the preliminary equilibrium value, the target equilibrium value is obtained as 0.5. During the energy transfer process, the SOC value of each single battery in the energy transfer pair is monitored in real time. After a period of time, single battery 8 reaches the target equilibrium value of 0.5. Stop the energy transfer from single battery 3 to single battery 8, and output the transferred charge amount of this energy transfer pair, which is assumed to be 400C. Compare the SOC value of single battery 3 with the target equilibrium value of 0.5. The SOC value of single battery 3 is 0.75, which is greater than the target equilibrium value. At this time, the single battery with the lowest SOC value in the shortage state is single battery 6 (SOC = 0.2), and a new energy transfer pair is formed: single battery 3 transfers energy to single battery 6. Assume that during the subsequent energy transfer process, the SOC values of single battery 3 and single battery 6 both reach 0.5, they are equal and equal to the target equilibrium value, then stop this energy transfer and do not perform any additional processing.

[0142] Configure the transfer threshold. When the energy transfer ends, count the total transferred charge amount of all energy transfer pairs, compare it with the target transferred charge amount, calculate the transfer deviation. If the transfer deviation is greater than the transfer threshold, recalculate the state of charge data of the battery pack to determine whether the battery pack is load-balanced; if the battery pack is load-balanced, no operation is performed, otherwise, re-adopt the active equalization strategy to re-perform energy transfer on the battery pack; configuring the transfer threshold and performing deviation calculation can effectively evaluate the completion of energy transfer. If the transfer deviation is too large, recalculate the state of charge data and make a judgment to ensure that the battery pack truly achieves load balance.

[0143] During the implementation of the active balancing strategy, set the parameter range of the working state data, and monitor the working state data of the battery pack in real time. If the working state data of a single battery exceeds its parameter range, stop the energy transfer operation and issue an energy transfer warning; setting the parameter range of the working state data and monitoring it in real time can promptly detect abnormal conditions that occur during the balancing process of the battery pack. Exemplarily, when the voltage, current, or temperature of a single battery exceeds the normal range, it may trigger battery failures or even safety issues. Stopping the energy transfer operation and issuing a warning in a timely manner can prevent the problem from deteriorating further and ensure the use safety of electric two-wheel and three-wheel vehicles. At the same time, the warning information can remind users and maintenance personnel to check and maintain the battery pack in a timely manner, reduce maintenance costs, and improve the usability of the vehicle.

[0144] When the load balance difference level of the battery pack is severely unbalanced, adopt an abnormal warning strategy. If the battery pack is in the charging state, immediately cut off the charging power supply to prevent the charging process from continuing, and avoid more serious damage to the battery pack caused by overcharging, such as safety hazards like battery bulging and fire. Send a push notification to the user's mobile phone for load balance warning to remind the user to repair the vehicle.

[0145] If the battery pack is in the discharging state, gradually reduce the discharging current of the battery pack to prevent permanent damage to individual single batteries due to over-discharging, and issue a load balance warning through the flashing of the vehicle dashboard indicator light to remind the user to stop using the vehicle and repair the vehicle.

[0146] The communication display module is used to send the working state data of the battery pack, warning information, and the driving state information of the vehicle to the vehicle dashboard for display through wireless communication technology, enabling users to understand the working state of the battery in real time.

[0147] The warning information includes: battery pack abnormal warning, load imbalance warning, and energy transfer abnormal warning.

[0148] When the data analysis module determines that the battery pack is abnormal, it includes the type of battery pack abnormality, such as voltage abnormality, current abnormality, temperature abnormality, etc., the timestamp when the abnormality occurs, and the abnormal single battery number; when it is determined that the battery pack has load imbalance, the warning information includes the degree of load imbalance, including mild imbalance, moderate imbalance, and severe imbalance; during the implementation of the active balancing strategy, if the working state data of a single battery exceeds the parameter range, the warning information includes the type of working state data that exceeds the range, the specific value, and the abnormal single battery number.

[0149] In this embodiment, a module with Bluetooth and CAN bus communication functions is selected, such as an industrial communication display control board, which integrates a high-performance microcontroller and can quickly process and transmit data. A dedicated controller adapted for electric tricycles and electric two-wheelers is used, which has a CAN bus interface and receives and processes data from the communication display module. An intelligent instrument panel with a liquid crystal display screen and indicator lights is selected, which supports Bluetooth connection and can clearly display various information. The state monitoring module collects the voltage, current, and temperature data of each single battery in the battery pack in real time. The communication display module then sends the battery pack working state data to the vehicle instrument panel through wireless communication technology. The LCD screen on the instrument panel displays this data in the form of numbers and charts, and users can intuitively see the real-time state of each single battery. When the data analysis module or the load balancing module detects an abnormality in the battery pack or a load balancing warning, for example, the voltage of a single battery exceeds the normal range. Suppose the voltage of the 5th single battery drops to 3.2V, which is lower than the lower limit of the normal range. This abnormal information is sent to the communication display module. The communication display module sends the warning information to the vehicle instrument panel through wireless communication technology. The red indicator light on the instrument panel lights up, and at the same time, the LCD screen displays a prompt message of "Battery abnormality, please check", reminding the user to handle it in time. The state monitoring module obtains the driving state information of the vehicle through a speed sensor, an acceleration sensor, and a load sensor. For example, the speed is 25 km / h, the acceleration is 0.5 m / s², and the load is 100 kg. The communication display module sends the vehicle driving state information to the vehicle instrument panel through wireless communication technology. The LCD screen on the instrument panel displays the current speed, acceleration value, and load information, allowing users to understand the driving condition of the vehicle in real time.

[0150] Embodiment 2

[0151] Please refer to Figure 7 , this embodiment introduces a load balancing new energy battery energy efficiency optimization method, including the following steps:

[0152] Step S1: Collect the working state data of each single battery in the battery pack during charging and discharging, including voltage data, current data, and temperature data, and obtain the driving state information of the vehicle, including speed, acceleration, and load;

[0153] Step S2: Based on the working state data of the battery pack, extract single-cell deviation data for single-point data monitoring. If abnormal data is detected, perform abnormal data analysis, and judge whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, calculate the state of charge data of the battery pack to judge whether the battery pack is load-balanced;

[0154] Step S3: When it is determined that there is a load imbalance in the battery pack, obtain the SOC values of each single battery to evaluate its load balance difference level, and formulate a load balance strategy according to the load balance difference level, including a simple balancing strategy, an active balancing strategy, and an abnormal warning strategy, to balance the load of the battery pack;

[0155] Step S4: Send the battery pack working state data, warning information, and vehicle driving state information to the vehicle dashboard for display through wireless communication technology.

[0156] Preferably, the specific steps for determining whether the battery pack is load balanced include:

[0157] According to the working state data of each single battery in the battery pack during charging and discharging collected, extract the single-cell deviation data of the battery pack by calculating the extreme value difference of each working state data of the battery pack;

[0158] Configure a single-cell deviation threshold, and based on the single-cell deviation data of the battery pack, perform single-point data monitoring. If there is single-cell deviation data greater than the corresponding single-cell deviation threshold, it is determined that the single-point data is abnormal, and the current working state data is marked as abnormal data, otherwise no processing is performed;

[0159] If abnormal data is detected, perform abnormal data analysis, further count the frequency of occurrence of abnormal data, and set a monitoring interval to measure the number of times of collecting working state data for monitoring;

[0160] Configure an equalization threshold. If the proportion of the number of times abnormal data appears in the monitoring interval to the total number of collections is greater than the equalization threshold, it is determined that the battery pack is abnormal, and calculate the state of charge data of the battery pack. The state of charge data includes the SOC value and the SOC change rate; otherwise, obtain the duration and interval time of the occurrence of abnormal data in the monitoring interval;

[0161] Set a duration threshold and an interval threshold. If the duration of the occurrence of abnormal data in the monitoring interval is greater than the duration threshold, or the interval time of the occurrence of abnormal data is less than the interval threshold, it is determined that the battery pack is abnormal, and calculate the state of charge data of the battery pack, otherwise no processing is performed;

[0162] Set a load balance threshold, obtain the SOC change rate of each single battery in the battery pack in the representative interval. If the absolute value of the difference between the SOC change rates of two single batteries in the battery pack is greater than the load balance threshold, it is determined that the battery pack has a load imbalance, otherwise no processing is performed.

[0163] Preferably, the specific steps for formulating a load balance strategy include:

[0164] When it is determined that there is a load imbalance in the battery pack, the load balance difference level of the battery pack is evaluated according to the SOC value of each single battery, and it is divided into mild imbalance, moderate imbalance and severe imbalance;

[0165] When the load balance difference level of the battery pack is mild imbalance, a simple balancing strategy is adopted to adjust the load of the battery pack;

[0166] When the load balance difference level of the battery pack is moderate imbalance, an active balancing strategy is adopted to adjust the load of the battery pack;

[0167] When the load balance difference level of the battery pack is severe imbalance, an abnormal warning strategy is adopted. If the battery pack is in the charging state, the charging power supply is immediately cut off to prevent the charging process from continuing, and a load balance warning is sent by pushing a notification to the user's mobile phone to remind the user to repair the vehicle;

[0168] If the battery pack is in the discharging state, the discharging current of the battery pack is gradually reduced, and a load balance warning is given by flashing the indicator light on the vehicle dashboard to remind the user to stop using the vehicle and repair the vehicle.

[0169] Preferably, the simple balancing strategy specifically includes:

[0170] Obtain the SOC value of each single battery in the current battery pack and the average SOC value of the battery pack;

[0171] If the battery pack is in the charging state, configure a charging acceleration threshold and a charging slowdown threshold, and divide the single batteries of the battery pack into a charging acceleration group, a charging maintenance group and a charging slowdown group according to the average SOC value of the battery pack;

[0172] Divide the single batteries with SOC values less than the charging acceleration threshold into the charging acceleration group, increase their charging current to speed up the charging speed, and determine the increased charging current according to the difference between the SOC value of the single battery and the charging acceleration threshold;

[0173] Divide the single batteries with SOC values greater than the charging slowdown threshold into the charging slowdown group, reduce their charging current to slow down the charging process, and determine the slowed-down charging current according to the difference between the SOC value of the single battery and the charging slowdown threshold;

[0174] Divide the single batteries with SOC values greater than or equal to the charging acceleration threshold and less than or equal to the charging slowdown threshold into the charging maintenance group and keep the charging current unchanged;

[0175] If the battery pack is in the discharging state, configure a discharging acceleration threshold and a discharging slowdown threshold, and divide the single batteries of the battery pack into a discharging acceleration group, a discharging maintenance group and a discharging slowdown group according to the average SOC value of the battery pack; adjust the discharging currents of the discharging acceleration group and the discharging slowdown group respectively;

[0176] Configure a stop threshold, monitor the load status of the battery pack after adjusting the charge and discharge current of the mild imbalance, and obtain the SOC value of each single battery in the battery pack in real time. When the range of the SOC values of the battery pack is less than the stop threshold, restore the charge and discharge current of the single battery in the battery pack.

[0177] Preferably, the specific steps of the active balancing strategy include:

[0178] Obtain the SOC value of each single battery in the current battery pack and the average SOC value of the battery pack, and use the average SOC value of the battery pack as the preliminary balancing value;

[0179] Compare the SOC value of each single battery with the preliminary balancing value. For the single battery with an SOC value higher than the preliminary balancing value, mark it as the affluent state; for the single battery with an SOC value lower than the preliminary balancing value, mark it as the deficit state;

[0180] According to the SOC value of each single battery and the preliminary balancing value, combined with the rated capacity of the single battery, calculate the target transferred charge amount;

[0181] Obtain the charge and discharge current of each single battery in the current battery pack, combine the SOC value of each single battery with the target transferred charge amount, formulate an energy transfer plan, generate energy transfer pairs, and perform energy transfer on the single batteries in the battery pack;

[0182] Configure a transfer threshold. When the energy transfer ends, count the total transferred charge amount of all energy transfer pairs, compare it with the target transferred charge amount, calculate the transfer deviation. If it is greater than the transfer threshold, recalculate the state of charge data of the battery pack and determine whether the battery pack is load balanced;

[0183] If the battery pack is load balanced, do not perform any operation. Otherwise, re - adopt the active balancing strategy and perform energy transfer on the battery pack again;

[0184] During the implementation of the active balancing strategy, set the parameter range of the working state data, and monitor the working state data of the battery pack in real time. If the working state data of a single battery exceeds its parameter range, stop the energy transfer operation and issue an energy transfer warning.

[0185] Working principle and its effect:

[0186] A load - balanced new - energy battery energy - efficiency optimization system and method aims to improve the performance and safety of new - energy batteries and optimize the user experience.

[0187] The state monitoring module collects in real time the working state data such as the voltage, current, and temperature of the individual batteries in the battery pack, as well as the vehicle driving state information, providing a basis for subsequent analysis. The data analysis module extracts the individual deviation data by calculating the extreme value difference of the working state data, compares it with the individual deviation threshold, determines whether there is single-point data anomaly, and marks the abnormal data. This can timely detect local anomalies in the battery pack, provide accurate data support for subsequent analysis, and ensure the stable operation of the battery pack.

[0188] After abnormal data is detected, the frequency, duration, and interval time of the abnormal data are counted, and it is judged whether the battery pack is abnormal by combining the balance, duration, and interval thresholds. If it is abnormal, the median filtering algorithm is used to process the current data, the SOC value of the individual battery is calculated based on the ampere-hour integration method, the SOC change rate is calculated by combining the SOC statistic threshold and the sliding window, and it is judged whether the battery pack is load-balanced by the load balance threshold. The state of the battery pack is accurately judged, adjusted in advance, avoiding the decline of battery performance and shortening of life, and extending the service life of the battery pack.

[0189] The load balancing module evaluates the load balance difference level according to the SOC value of the individual battery and adopts different strategies. When there is a slight imbalance, the simple balancing strategy divides the charging or discharging groups according to the average SOC value of the battery pack and the set threshold, adjusts the current, and restores the normal current when the range of the SOC value of the battery pack is less than the stop threshold, which can quickly balance the power, improve the charging efficiency, and avoid overcharging and over-discharging. When there is a moderate imbalance, the active balancing strategy marks the individual batteries in the rich and poor states, calculates the target charge amount, formulates an energy transfer plan, dynamically adjusts the balance value, monitors and adjusts the energy transfer in real time, decides whether to re-balance according to the transfer deviation, and at the same time monitors the working state data and gives an early warning when abnormal, further optimizing the balance of the battery pack. When there is a severe imbalance, the abnormal warning strategy cuts off the power supply and pushes a notification to the user's mobile phone during charging, and reduces the current and reminds the user through the flashing of the dashboard indicator during discharging, avoiding serious damage to the battery and ensuring the safety of the user.

[0190] The communication display module sends the working state of the battery pack, the warning information, and the vehicle driving state information to the vehicle dashboard through wireless communication, facilitating the user to understand the relevant information in real time, reasonably plan the itinerary, respond to the problems of the battery pack in time, and improve the user experience.

[0191] The above is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the idea of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, several improvements and refinements made without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A load balancing new energy battery energy efficiency optimization system, characterized in that: It includes a status monitoring module, a data analysis module, a load balancing module and a communication display module; The state monitoring module is used to collect the working state data of each single cell in the battery pack during charging and discharging, including voltage data, current data and temperature data, and obtain the driving state information of the vehicle, including speed, acceleration and load; The data analysis module is used to extract the single-cell deviation data for single-point data monitoring based on the working status data of the battery pack. If abnormal data is detected, abnormal data analysis is performed to determine whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, the state of charge data of the battery pack is calculated to determine whether the battery pack is load balanced. The load balancing module is used to obtain the SOC value of each single battery to evaluate the load balance difference level when it is determined that the battery pack has load imbalance, and formulate a load balancing strategy according to the load balance difference level, including a simple balancing strategy, an active balancing strategy and an abnormal warning strategy, to balance the battery pack load; The specific steps of the active balancing strategy include: Obtain the SOC value of each single cell of the current battery pack and the average SOC value of the battery pack, and use the average SOC value of the battery pack as the initial balancing value; Compare the SOC value of each single cell with the preliminary equilibrium value, and mark the single cell with an SOC value higher than the preliminary equilibrium value as a rich state; and mark the single cell with an SOC value lower than the preliminary equilibrium value as a scarce state; According to the SOC value and preliminary equalization value of each single battery, combined with the rated capacity of the single battery, the target transfer charge amount is calculated; Obtain the charge and discharge current of each single cell of the current battery pack, combine the SOC value of each single cell with the target transfer charge, formulate an energy transfer plan, generate an energy transfer pair, and perform energy transfer on the single cells of the battery pack; Configure the transfer threshold. When the energy transfer is completed, count the total amount of charge transferred by all energy transfer pairs, compare it with the target transfer charge, and calculate the transfer deviation. If it is greater than the transfer threshold, recalculate the state of charge data of the battery pack to determine whether the battery pack is load balanced. If the battery pack load is balanced, no operation is performed, otherwise the active balancing strategy is adopted again to transfer energy to the battery pack again; During the implementation of the active balancing strategy, the parameter range of the working status data is set, and the working status data of the battery pack is monitored in real time. If the working status data of a single battery exceeds its parameter range, the energy transfer operation is stopped and an energy transfer warning is issued; The communication display module is used to send the battery pack working status data, warning information and vehicle driving status information to the vehicle dashboard for display through wireless communication technology.

2. A load balancing new energy battery energy efficiency optimization system as claimed in claim 1, characterized in that: The specific steps of determining whether the battery pack is load balanced include: According to the collected working state data of each single battery in the battery pack during charging and discharging, the single battery deviation data of the battery pack is extracted by calculating the extreme value difference of each working state data of the battery pack; Configure the cell deviation threshold, and perform single-point data monitoring based on the cell deviation data of the battery pack. If the cell deviation data is greater than the corresponding cell deviation threshold, it is determined to be single-point data abnormal, and the current working status data is marked as abnormal data. Otherwise, no processing is performed; If abnormal data is detected, abnormal data analysis is performed to count the frequency of abnormal data occurrence and set a monitoring interval to measure the number of times data is collected for monitoring working status; Configure the balancing threshold. If the ratio of the number of abnormal data occurring in the monitoring interval to the total number of acquisitions is greater than the balancing threshold, the battery pack is determined to be abnormal and the state of charge data of the battery pack is calculated. The state of charge data includes the SOC value and the SOC change rate. Otherwise, the duration and interval time of the abnormal data occurring in the monitoring interval are obtained.

3. A load balancing new energy battery energy efficiency optimization system as claimed in claim 2, characterized in that: The specific step of determining whether the battery pack is load balanced also includes: Set the duration threshold and interval threshold. If the duration of abnormal data in the monitoring interval is greater than the duration threshold, or the interval time of abnormal data is less than the interval threshold, the battery pack is judged to be abnormal and the state of charge data of the battery pack is calculated. Otherwise, no processing is performed. Set the load balancing threshold, obtain the SOC change rate of each single cell in the battery pack in the representative interval, and if the absolute value of the difference in the SOC change rate of two single cells in the battery pack is greater than the load balancing threshold, it is determined that the battery pack has load imbalance, otherwise no processing is performed.

4. A load balancing new energy battery energy efficiency optimization system as claimed in claim 3, characterized in that: The specific steps of calculating the state of charge data of the battery pack include: Obtain the current data of the battery pack collected within the monitoring interval, and use the median filter algorithm to process the collected current data to remove abnormal current values; According to the ampere-hour integration method, based on the current data in the monitoring interval processed by the median filter algorithm, the SOC value of each single battery at each moment in the monitoring interval is calculated respectively; Configure SOC statistical thresholds, including SOC extreme value threshold and SOC standard deviation threshold, and calculate the statistics of the battery pack SOC value, including extreme value and standard deviation, based on the SOC value of each single battery in the monitoring interval; If the statistics of the battery pack SOC values ​​within the monitoring interval are all less than the corresponding SOC statistic threshold, the SOC change rate is set to 0; Otherwise, according to the statistics of the battery pack SOC value, a sliding window is set to obtain the range and the range of the battery pack SOC value in the sliding window respectively, and the sliding window is selected according to the range and the range as the representative interval to calculate the SOC change rate of each single cell SOC value in the representative interval.

5. A load balancing new energy battery energy efficiency optimization system as claimed in claim 1, characterized in that: The specific steps of formulating the load balancing strategy include: When it is determined that the battery pack has load imbalance, the load balance difference level of the battery pack is evaluated according to the SOC value of the single battery, and it is divided into mild imbalance, moderate imbalance and severe imbalance; When the battery pack load balance difference level is slightly unbalanced, a simple balancing strategy is adopted to adjust the battery pack load; When the battery pack load balance difference level is moderately unbalanced, an active balancing strategy is adopted to adjust the battery pack load; When the load balance difference level of the battery pack is severely unbalanced, an abnormal warning strategy is adopted. If the battery pack is in a charging state, the charging power supply is immediately cut off, and a load balance warning is issued by sending a push notification to the user's mobile phone; If the battery pack is in a discharging state, the battery pack discharge current is reduced, and the indicator light on the vehicle dashboard flashes to provide a load balancing warning.

6. A load balancing new energy battery energy efficiency optimization system as claimed in claim 5, characterized in that: The simple equilibrium strategy specifically includes: Get the SOC value of each single cell of the current battery pack and the average SOC value of the battery pack; If the battery pack is in a charging state, configure the charging acceleration threshold and the charging slowdown threshold, and divide the single cells of the battery pack into a charging acceleration group, a charging maintenance group, and a charging slowdown group according to the average SOC value of the battery pack; The single cells whose SOC value is less than the charging acceleration threshold are divided into the charging acceleration group, the charging current is increased, the charging speed is accelerated, and the increased charging current is determined according to the difference between the single cell SOC value and the charging acceleration threshold; The single cells whose SOC value is greater than the charge slowdown threshold are divided into the charge slowdown group, the charging current is reduced, the charging process is slowed down, and the charging current after slowdown is determined according to the difference between the single cell SOC value and the charge slowdown threshold; The single cells whose SOC value is greater than or equal to the charging acceleration threshold and whose SOC value is less than or equal to the charging slowdown threshold are divided into the charging maintenance group to maintain the charging current unchanged; If the battery pack is in a discharging state, configure the discharge acceleration threshold and the discharge slowdown threshold, and divide the single cells of the battery pack into a discharge acceleration group, a discharge maintenance group, and a discharge slowdown group according to the average SOC value of the battery pack; and adjust the discharge current of the discharge acceleration group and the discharge slowdown group respectively; Configure the stop threshold, monitor the load status of the battery pack after the slight imbalance charge and discharge current is adjusted, obtain the SOC value of each single cell of the battery pack in real time, and restore the charge and discharge current of the single cell of the battery pack when the extreme difference of the SOC value of the battery pack is less than the stop threshold.

7. A load balancing new energy battery energy efficiency optimization system as claimed in claim 1, characterized in that: The specific steps of formulating the energy transfer scheme include: The single cells marked as rich and scarce are sorted from large to small according to their SOC values, and the initial energy transfer direction of the battery pack is determined according to the sorting results, namely: Determine the initial energy transfer direction as follows: the single cell with the highest SOC value in the rich state transfers energy to the single cell with the lowest SOC value in the scarce state, the single cell with the second highest SOC value in the rich state transfers energy to the single cell with the second lowest SOC value in the scarce state, and so on, to form a one-to-one energy transfer pair; According to the charge and discharge current of each single cell of the battery pack, the preliminary balancing value is dynamically adjusted as the target balancing value; During the energy transfer process, the SOC value of each single cell in the energy transfer pair is monitored in real time. If a single cell in the energy transfer pair reaches the target balance value, the energy transfer is stopped and the charge transferred by the energy transfer pair is output; The SOC value of the other single cell in the energy transfer pair is compared with the target balance value. If it is greater than the target balance value, the energy transfer direction is updated, that is, the single cell transfers energy to the single cell with the lowest SOC value in the starvation state to form a new energy transfer pair; otherwise, no processing is performed; During the energy transfer process, if the SOC values ​​of the single cells in the energy transfer pair are equal, the energy transfer is stopped. If the SOC value of the single cell is equal to the target balance value, no processing is performed. If the SOC value of the single cell is greater than the target balance value, the energy transfer direction is updated, otherwise no processing is performed.

8. A load balancing new energy battery energy efficiency optimization system as claimed in claim 7, characterized in that: The specific steps of dynamically adjusting the preliminary equilibrium value include: Obtain the charge and discharge current value of each single cell of the battery pack, and calculate the charge and discharge power change of each single cell in combination with the current value collection interval; According to the change in charge and discharge power of the single cell, the SOC value of each single cell is updated, and the average SOC value of the battery pack is recalculated as the target balancing value.

9. A load balancing new energy battery energy efficiency optimization system as claimed in claim 5, characterized in that: The specific steps of evaluating the battery pack load balancing difference level include: Obtain the SOC value of each single cell of the battery pack within the monitoring interval, and obtain the current stored charge of the battery pack based on the rated capacity of each single cell; Configure the growth trend threshold, obtain the range of the battery pack SOC value within the monitoring interval, and perform linear fitting to obtain the slope of the fitting curve. If it is greater than the growth trend threshold, it is determined that the range of the battery pack SOC value has a growth trend and is classified as severely unbalanced. Otherwise, it is determined that there is no growth trend in the range of the SOC value of the battery pack, then the range mean of the SOC value of the battery pack in the monitoring interval is calculated, and a first imbalance threshold is set, including a first imbalance lower threshold and a first imbalance upper threshold, and the first imbalance threshold is dynamically adjusted according to the current stored charge of the battery pack and the rated total charge of the battery pack, and a second imbalance threshold after dynamic adjustment is obtained, including a second imbalance lower threshold and a second imbalance upper threshold; If the mean of the range of the battery pack SOC values ​​in the monitoring interval is greater than the second upper imbalance threshold, it is classified as severe imbalance; if the mean of the range of the battery pack SOC values ​​in the monitoring interval is less than the second lower imbalance threshold, it is classified as mild imbalance; otherwise, it is classified as moderate imbalance.

10. A method for optimizing energy efficiency of a load-balanced new energy battery, which is implemented based on a load-balanced new energy battery energy efficiency optimization system according to any one of claims 1 to 9, characterized in that: The following steps are involved: Collect the working status data of each single cell in the battery pack during charging and discharging, including voltage data, current data and temperature data, and obtain the driving status information of the vehicle, including speed, acceleration and load; Based on the working status data of the battery pack, extract the single-cell deviation data for single-point data monitoring. If abnormal data is detected, perform abnormal data analysis to determine whether the battery pack is abnormal within the monitoring interval. If the battery pack is abnormal, calculate the state of charge data of the battery pack to determine whether the battery pack is load balanced. When it is determined that the battery pack has load imbalance, the SOC value of each single battery is obtained to evaluate its load balance difference level, and a load balancing strategy is formulated according to the load balance difference level, including a simple balancing strategy, an active balancing strategy and an abnormal warning strategy, to balance the battery pack load; The battery pack working status data, warning information and vehicle driving status information are sent to the vehicle dashboard for display via wireless communication technology.

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