Load balance new energy battery energy efficiency optimization system and method

Abstract

The invention discloses a load balance new energy battery energy efficiency optimization system and method, and belongs to the field of battery energy efficiency optimization, and the method comprises the steps: extracting monomer deviation data based on the working state data of a battery pack, carrying out the single-point data monitoring, carrying out the abnormal data analysis if abnormal data is monitored, and carrying out the data analysis if the battery pack is abnormal; if yes, judging whether the load of the battery pack is balanced or not by calculating charge state data of the battery pack; when it is judged that the load of the battery pack is unbalanced, the SOC value of each single battery is obtained, the load balance difference level of each single battery is evaluated, a load balance strategy is made according to the load balance difference level, and the working state data of the battery pack, the early warning information and the driving state information of the vehicle are sent to a vehicle instrument panel through the wireless communication technology to be displayed. The problems of comprehensively monitoring the battery pack in real time, accurately judging the load balance condition of the battery pack, optimizing the energy efficiency of the battery by adopting a differentiation strategy according to the load unbalance degree and prolonging the service life of the battery are solved.

Description

Technical Field

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

[0002] As the key power source for electric two-wheelers, electric three-wheelers and other means of transportation, new energy batteries are increasingly widely used. However, new energy batteries face many challenges in practical applications. On the one hand, different battery cells have differences in production processes and material properties, which makes it very easy for the battery pack to have load imbalance during the charging and discharging process. For example, a single cell may bear more load during discharge due to its high internal resistance, resulting in premature exhaustion of power, affecting the performance and life of the entire battery pack. On the other hand, the driving conditions of electric two-wheelers and three-wheelers are complex and changeable. When they frequently start and stop in congested sections of the city, or encounter different road conditions such as climbing and bumping on rural roads, and carry different weights of goods, the battery load fluctuates greatly, further exacerbating the problem of load imbalance. Load imbalance not only reduces the available capacity of the battery pack, but also causes some batteries to be overcharged and discharged, shortening the battery life and increasing replacement costs. At the same time, battery energy efficiency also needs to be improved urgently. Inefficient energy conversion means that the vehicle's cruising range is limited and cannot meet the growing travel and use needs of users.

[0003] The Chinese patent application with publication number CN114987233A discloses a charging and swapping control system and control method for a low-speed electric vehicle. The charging and swapping control system includes: a first high-voltage control component; a second high-voltage control component; a battery main control module, which controls the working state 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-charge voltage of the power load device. Although the prior art realizes the small current pre-charging between the unbalanced battery packs during the battery swap process, the voltage platform is consistent, and the safety hazard that may be caused by the instantaneous "sparking" phenomenon of the battery packs in parallel when there is a large voltage difference during the battery swap action is eliminated. It still fails to solve the problem of comprehensive and real-time monitoring of the working state of each single battery in the battery pack during the charging and discharging process, as well as the vehicle driving state information; accurately judging whether the battery pack is load balanced, rather than only focusing on the battery pack voltage balance during battery swap; when the battery pack is unbalanced, adopt targeted strategies according to different degrees of imbalance to optimize the battery energy efficiency and extend the battery life. 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] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a load-balanced new energy battery energy efficiency optimization system and method, which solves the problems of comprehensive real-time monitoring of the charging and discharging working status of the battery pack single cells and the driving status of the vehicle; accurately determining the load balance status of the battery pack; and adopting differentiated strategies according to the degree of load imbalance to optimize battery energy efficiency and extend battery life.

[0005] To achieve the above object, the present invention provides the following technical solutions: A load-balanced new energy battery energy efficiency optimization system, comprising a state monitoring module, a data analysis module, a load balancing module and a communication display module; The status monitoring module is used to 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; 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 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.

[0006] Specifically, 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.

[0007] Specifically, the specific steps of determining whether the battery pack is load balanced also include: 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.

[0008] Specifically, 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.

[0009] Specifically, the steps to formulate a 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 to prevent the charging process from continuing. A push notification is sent to the user's mobile phone to issue a load balance warning to remind the user to inspect the vehicle. If the battery pack is in a discharging state, the discharge current of the battery pack will be gradually reduced, and the indicator light on the vehicle dashboard will flash to issue a load balancing warning to remind the user to stop using the vehicle and have it repaired.

[0010] Specifically, the simple equilibrium strategy 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.

[0011] Specifically, 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.

[0012] Specifically, the specific steps for formulating an 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.

[0013] Specifically, 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 SOC mean of the battery pack is recalculated as the target balancing value.

[0014] Specifically, the specific steps of evaluating the battery pack load balance 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.

[0015] A method for optimizing energy efficiency of a load-balanced new energy battery comprises the following steps: 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.

[0016] Beneficial effects of the present invention: 1. Real-time collection of single cell voltage, current, temperature data and vehicle driving status information provides a comprehensive basis for data analysis. The data analysis module uses complex algorithms to extract single cell deviation data from working status data, conducts detailed single-point data monitoring, accurately determines whether the battery pack is abnormal and whether the load is balanced, and promptly detects potential problems of single cells inside the battery pack to avoid problems from worsening, thereby extending the overall battery life.

[0017] 2. Implement different strategies based on the assessed load balance difference level. When there is a slight imbalance, the simple balance strategy takes effect, and when there is a moderate imbalance, the active balance strategy intervenes. During the energy transfer process, real-time monitoring and flexible adjustments are made to ensure that the balance of the battery pack is continuously optimized, further improving the performance and service life of the battery pack.

[0018] 3. When the battery pack is severely unbalanced, cut off the power supply immediately during charging to prevent serious safety hazards such as battery bulging and fire caused by overcharging; gradually reduce the discharge current during discharge to avoid permanent damage caused by excessive discharge of individual cells. At the same time, by sending push notifications to the user's mobile phone and flashing the indicator light on the vehicle dashboard, the user is informed in time that the vehicle needs to be repaired to protect the user's life and property. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural schematic diagram of a load balancing new energy battery energy efficiency optimization system of the present invention; Figure 2 A flowchart of specific steps for determining whether a battery pack is load balanced according to the present invention; Figure 3 A schematic diagram of formulating a load balancing strategy for the present invention; Figure 4 A flowchart of specific steps for evaluating the load balance difference level of a battery pack according to the present invention; Figure 5 A flowchart of the specific steps of the simple balancing strategy of the present invention; Figure 6 A flowchart of specific steps of the active balancing strategy of the present invention; Figure 7The present invention is a flow chart of a method for optimizing energy efficiency of a load-balanced new energy battery. DETAILED DESCRIPTION

[0020] Example 1

[0021] See also Figure 1 ,This embodiment introduces a load balancing new energy battery energy efficiency optimization system, including a state monitoring module, a data analysis module, a load balancing module and a communication display module; The status monitoring module is used to 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; In this embodiment, through sensing technology, whether the vehicle is running or in a static state after the vehicle is turned off, the working status data of each single cell in the battery pack is collected in real time. The working status data includes voltage data, current data and temperature data, among which the voltage data is used to capture subtle changes in battery voltage; the current data is used to reflect the battery charging and discharging current; the temperature data collection is used to monitor abnormal fluctuations in battery temperature, providing a reliable data basis for subsequent battery status analysis. Comprehensively obtain the vehicle's driving status information, covering speed, acceleration and load. Use speed sensors to quickly respond to changes in vehicle speed; acceleration sensors capture changes in acceleration during vehicle starting, acceleration, deceleration, braking, etc.; load sensors are used to measure vehicle load, thereby providing a strong basis for judging the load conditions of the battery under different driving conditions.

[0022] 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. See also Figure 2 Preferably, the specific steps of determining whether the battery pack is load balanced include: According to the collected working state data of each single cell in the battery pack during charging and discharging, 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. The single cell deviation data includes: voltage deviation data, current deviation data and temperature deviation data. The calculation method of single cell deviation data is as follows: ; in, It is at the moment The battery pack collected Individual deviation data of working status data, The value of , respectively represent voltage deviation data, current deviation data and temperature deviation data, It is at the moment The collected battery pack The first Working status data, is the total number of cells in the battery pack, is a maximum function, is a minimum function; Configure the cell deviation threshold, which includes voltage deviation threshold, current deviation threshold and temperature deviation threshold. Perform single-point data monitoring based on the cell deviation data of the battery pack. If there is cell deviation data 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. For example, the voltage deviation threshold is set to 0.1V, the current deviation threshold is set to 0.5A, and the temperature deviation threshold is set to 0.5℃. When the calculated voltage deviation data is greater than 0.1V, the voltage data at that moment is marked as abnormal data.

[0023] If abnormal data is detected, abnormal data analysis is performed to further count the frequency of abnormal data occurrence and set a monitoring interval to measure the number of times the monitoring working status data is collected. For example, if the monitoring interval is set to 100 collections, the proportion of the number of abnormal data occurrences in the monitoring interval to the total number of collections is calculated; 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. Not only the frequency should be paid attention to, but also the duration and interval time of the abnormal data should be analyzed. If the abnormal data continues to occur or the interval time is short, it indicates that the problem of the battery pack is more serious. If the abnormal data occurs occasionally and the interval time is long, it may be caused by accidental factors and needs to be continuously observed.

[0024] 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. Preferably, the specific steps of calculating the state of charge data of the battery pack include: The current data of the battery pack collected within the monitoring interval is obtained. Since the driving conditions of electric two-wheeled and three-wheeled vehicles are complex, the current fluctuates frequently, and they are susceptible to electromagnetic interference, the median filter algorithm is used to process the collected current data to remove the instantaneous abnormal current values. At the moment of vehicle starting, acceleration, braking, etc., the current will fluctuate greatly. These fluctuations are smoothed by median filtering to ensure the accuracy of the data.

[0025] 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 statistics threshold, the SOC change rate is set to 0; if the statistics of the battery pack SOC values ​​within the monitoring interval are all less than the corresponding SOC statistics threshold, it indicates that the state of charge difference between the single cells is small, and the battery pack can be considered to be in a relatively balanced state. At this time, the SOC change rate is set to 0. If the range or standard deviation exceeds a certain reasonable range, it means that the state of charge difference between the single cells is large, and there is a load imbalance.

[0026] Otherwise, according to the statistics of the battery pack SOC value, set the sliding window, which can be set to 10%-20% of the monitoring interval, obtain the range and the range of the battery pack SOC value in the sliding window, select the sliding window according to the range and as the representative interval, and calculate the SOC change rate of each single cell in the representative interval; by comparing the SOC change rate of different single cells, the charge and discharge differences of each single cell in the battery pack can be analyzed more deeply, and the degree and cause of load imbalance can be further determined. If the SOC change rate of some single cells is significantly higher than that of other batteries, it means that these batteries are charged and discharged faster during this time period and may be under a greater load.

[0027] Set the load balancing threshold and obtain the SOC change rate of each single cell in the battery pack in the representative interval. 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, that is, it is considered that the current battery pack is in a balanced state in terms of load distribution.

[0028] The load balancing module is used to obtain the SOC value of each single battery to evaluate its 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, so as to balance the charge state of each single battery; See also Figure 3 , preferably, 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; See also Figure 4 Preferably, the specific steps of evaluating the battery pack load balance difference level include: Get the SOC value of each single cell of the battery pack within the monitoring interval, and based on the rated capacity of each single cell, get the current stored charge of the battery pack, that is: ; in, is the current stored charge of the battery pack, The battery pack The rated capacity of each single cell, The battery pack The SOC value of each single battery, is the total number of cells in the battery pack; 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 the slope of the fitting curve 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 severe imbalance. During the charging and discharging process of electric two-wheeled and three-wheeled vehicles, if the SOC range shows an increasing trend, it means that the performance difference of the single cells in the battery pack is expanding, which will lead to unstable power and shortened cruising range during vehicle driving. Timely determination of severe imbalance can remind users and maintenance personnel to intervene as soon as possible to avoid further damage to the battery pack.

[0029] Otherwise, it is determined that there is no growth trend in the range of the battery pack SOC value, then the range mean of the battery pack SOC value 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. The first imbalance lower threshold is used to define the boundary between a mild imbalance and a moderate imbalance, and the second imbalance upper threshold is used to distinguish between a moderate imbalance and a severe imbalance. According to the current stored charge of the battery pack and the rated total charge of the battery pack, the first imbalance threshold is dynamically adjusted to obtain a dynamically adjusted second imbalance threshold, including a second imbalance lower threshold and a second imbalance upper threshold, that is: ; ; in, and is the second imbalance lower threshold and the second imbalance upper threshold after dynamic adjustment, and are the first imbalance lower threshold and the first imbalance upper threshold, is the total rated charge of the battery pack, and is the lower percentage of the battery pack's stored charge and the upper percentage of the battery pack's stored charge, and is the minimum and maximum value of the second imbalance lower threshold after dynamic adjustment, and is the minimum and maximum value of the second imbalance upper threshold after dynamic adjustment, and They are maximum value function and minimum value function respectively. For the high charge range, since the performance of the battery pack is relatively stable, in order to more strictly monitor the load balance, the first imbalance threshold is tightened. For the medium charge range, the first imbalance threshold is kept unchanged. For the low charge range, considering the performance fluctuation caused by factors such as the increase of battery internal resistance, the first imbalance threshold is relaxed. 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.

[0030] When the load balance difference level of the battery pack is slightly unbalanced, a simple balancing strategy is adopted; See also Figure 5 , preferably, the specific steps of the simple equilibrium strategy include: 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 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%; 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: ; 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 ; 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: ; 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, an example ; During the charging process, the simple balancing strategy can quickly replenish the power of single cells with a lower state of charge, and avoid overcharging of single cells with a higher state of charge, ensuring that the power of each single cell in the battery pack increases evenly. For electric two-wheeled and three-wheeled vehicles, it can improve the overall charging efficiency of the battery pack, reduce the charging time, and avoid affecting the battery life and safety due to overcharging of individual batteries. For example, in daily use, users can complete charging faster and do not have to worry about the battery being damaged by overcharging, which extends the service life of the battery pack and reduces the cost of use.

[0031] 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; Similarly, if the battery pack is in a discharging state, the discharge acceleration threshold and the discharge reduction threshold are configured, and the single cells of the battery pack are divided into a discharge acceleration group, a discharge maintenance group, and a discharge reduction group according to the average SOC value of the battery pack; the discharge currents of the discharge acceleration group and the discharge reduction group are adjusted respectively to achieve the balance of the battery pack; The single cells whose SOC value is less than the discharge slowdown threshold are divided into the discharge slowdown group, the discharge current is reduced, the discharge speed is slowed down, and the discharge current after slowdown is determined according to the difference between the single cell SOC value and the discharge slowdown threshold; The single cells whose SOC value is greater than the discharge acceleration threshold are divided into the discharge acceleration group, and their discharge current is increased. The discharge current after slowing down is determined according to the difference between the single cell SOC value and the discharge acceleration threshold; The single cells with SOC values ​​greater than or equal to the discharge slowdown threshold and SOC values ​​less than or equal to the discharge acceleration threshold are divided into the discharge maintenance group to maintain the discharge current unchanged; during the discharge process, a simple balancing strategy can make the discharge depth of each single cell tend to be consistent to avoid excessive discharge of individual batteries. This is crucial for the stable driving of electric two-wheeled and three-wheeled vehicles, which can ensure that the vehicle has stable power output during driving and will not suddenly lose power or drive abnormally due to excessive discharge of individual batteries. At the same time, by reasonably adjusting the discharge current, the discharge time of the battery pack can be extended and the vehicle's endurance can be improved.

[0032] 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.

[0033] See also Figure 6 When the load balance difference level of the battery pack is moderately unbalanced, an active balancing strategy is adopted. 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; The SOC value of each single cell is compared with the preliminary balance value. The single cell with an SOC value higher than the preliminary balance value is marked as a rich state; the single cell with an SOC value lower than the preliminary balance value is marked as a scarce state; the state information of each single cell is recorded for subsequent analysis and processing.

[0034] According to the SOC value and preliminary equalization value of each single cell, combined with the rated capacity of the single cell, the target transfer charge is calculated, that is: ; in, is the target transfer charge, is the initial equilibrium value, The battery pack The rated capacity of each single cell, The battery pack The SOC value of each single battery, The value range is , It is the total number of cells in the battery pack; accurately calculating the target transfer charge provides a quantitative basis for the formulation of the energy transfer plan. During the use of electric two-wheeled and three-wheeled vehicles, the charge state of the battery pack will continue to change. By accurately calculating the target charge, energy transfer can be reasonably arranged to ensure that the balance of the battery pack is effectively improved.

[0035] 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; Preferably, the specific steps of formulating the energy transfer scheme include: The single cells marked as rich state and scarce state are sorted from large to small according to the SOC values ​​of the single cells. If there are single cells with the same SOC value, they are sorted again from left to right according to the installation position of the single cells. The initial energy transfer direction of the battery pack is determined according to the sorting result, that is, the initial energy transfer direction is determined as 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; for example, a battery pack of an electric tricycle has a total of 8 single cells, and the obtained After 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 scarce 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); the single cells in the rich state are sorted from large to small according to the SOC value. At this time, the SOC values ​​of single cells 5 and 7 are the same. From left to right according to the installation position of the single cells, assuming that single cell 5 is on the left of single cell 7, the order is single cell 3, single cell 5, single cell 7, single cell 9. For the single cells in the scarce state, the single cells are sorted from large to small according to the SOC value of the single cells. The SOC values ​​of single cells 2 and 4 are the same. From left to right according to the installation position, assuming that single cell 2 is on the left of single cell 4, the order is single cell 2, single cell 4, single cell 6, single cell 8. According to the sorting results, the preliminary energy transfer direction is determined to form a one-to-one energy transfer pair: monomer 3 transfers energy to monomer 8, monomer 5 transfers energy to monomer 6, monomer 7 transfers energy to monomer 4, and monomer 9 transfers energy to monomer 2.

[0036] 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. The specific steps of dynamically adjusting the preliminary balancing 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.

[0037] During the energy transfer process, the SOC value of each single cell in each energy transfer pair is monitored in real time. If there is a single cell in the energy transfer pair that reaches the target balance value, the energy transfer is stopped, the amount of charge transferred by the energy transfer pair is output, and 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. If there are single cells with the same SOC value, the single cell is selected from left to right according to the installation position of the single cell to form a new energy transfer pair; otherwise, no processing is performed; real-time monitoring and flexible adjustment of the energy transfer process can ensure that the energy transfer effect is optimal. The energy transfer pair that reaches the target balance value is stopped in time to avoid over-balancing, and the single cells that have not reached balance are continuously adjusted to ensure the continuous optimization of the balance of the battery pack.

[0038] 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; illustratively, after all single cells are dynamically updated according to the preliminary balance value, the target balance value is 0.5. During the energy transfer process, the SOC value of the single cell in each energy transfer pair is monitored in real time. After a period of time, single cell 8 reaches the target balance value of 0.5. Stop the energy transfer from single cell 3 to single cell 8, and output the amount of charge transferred by the energy transfer pair, assuming it is 400C. Compare the SOC value of single cell 3 with the target balance value of 0.5. The SOC value of single cell 3 is 0.75, which is greater than the target balance value. At this time, the single cell 6 (SOC=0.2) has the lowest SOC value in the starvation state, forming a new energy transfer pair: single cell 3 transfers energy to single cell 6. Assuming that in the subsequent energy transfer process, the SOC values ​​of monomer 3 and monomer 6 both reach 0.5, and the two are equal and equal to the target equilibrium value, the energy transfer is stopped without any additional processing.

[0039] 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 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, do not perform any operation. Otherwise, re-adopt the active balancing strategy and re-transfer energy to the battery pack. Configure the transfer threshold and perform deviation calculation to effectively evaluate the completion of the energy transfer. If the transfer deviation is too large, recalculate and judge the state of charge data to ensure that the battery pack is truly load balanced.

[0040] 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 cell exceeds its parameter range, the energy transfer operation is stopped and an energy transfer warning is issued; setting the working status data parameter range and real-time monitoring can promptly detect abnormal conditions that occur in the battery pack during the balancing process. For example, when the voltage, current or temperature of a single cell exceeds the normal range, it will cause battery failure or even safety problems. Stopping the energy transfer operation in time and issuing a warning can avoid further deterioration of the problem and ensure the safe use of electric two-wheeled and three-wheeled vehicles. At the same time, the warning information can remind users and maintenance personnel to check and maintain the battery pack in time, reduce maintenance costs, and improve vehicle availability.

[0041] 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 to prevent the charging process from continuing, thereby avoiding more serious damage to the battery pack due to overcharging, such as battery bulging, fire and other safety hazards. A push notification is sent to the user's mobile phone to issue a load balance warning to remind the user to inspect the vehicle; If the battery pack is in a discharging state, the discharge current of the battery pack will be gradually reduced to prevent permanent damage to individual cells due to over-discharge. The indicator light on the vehicle dashboard will flash to provide a load balancing warning to remind the user to stop using the vehicle and have it repaired.

[0042] 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 through wireless communication technology for display, so that the user can understand the battery working status in real time.

[0043] Warning information includes: battery pack abnormality warning, load imbalance warning and energy transfer abnormality warning; When the data analysis module determines that the battery pack is abnormal, it includes the type of battery pack abnormality, such as abnormal voltage, abnormal current, abnormal temperature, etc., the timestamp of the abnormality, 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 status data of a single battery exceeds the parameter range, the warning information includes the type of working status data that exceeds the range, the specific value, and the abnormal single battery number.

[0044] In this embodiment, a module with Bluetooth and CAN bus communication functions is selected, such as an industrial-grade communication display control panel, which integrates a high-performance microcontroller and can quickly process and transmit data. A dedicated controller adapted to electric tricycles and electric two-wheelers is used, which has a CAN bus interface to receive and process data from the communication display module. An intelligent dashboard with an LCD display and indicator light is selected, which supports Bluetooth connection and can clearly display various information. The status monitoring module collects the voltage, current and temperature data of each single cell in the battery pack in real time. The communication display module then sends the battery pack working status data to the vehicle dashboard through wireless communication technology. The LCD screen on the dashboard displays these data in the form of numbers and charts, and the user can intuitively see the real-time status of each single cell. When the data analysis module or the load balancing module detects that the battery pack is abnormal or there is a load balancing warning, for example, the voltage of a single cell exceeds the normal range, assuming that the voltage of the No. 5 single cell 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 dashboard through wireless communication technology. The red indicator light on the dashboard lights up, and the LCD screen displays the battery abnormality, please check the prompt information, reminding the user to deal with it in time. The status monitoring module obtains the vehicle's driving status information through the speed sensor, acceleration sensor and load sensor. For example, the speed is 25km / h, the acceleration is 0.5m / s², and the load is 100kg. The communication display module sends the vehicle's driving status information to the vehicle dashboard through wireless communication technology. The LCD screen on the dashboard displays the current speed, acceleration value, and load information, allowing users to understand the vehicle's driving status in real time.

[0045] Example 2

[0046] See also Figure 7 This embodiment introduces a load balancing new energy battery energy efficiency optimization method, including the following steps: Step S1: collecting 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 obtaining the driving state information of the vehicle, including speed, acceleration and load; Step S2: Based on the working status data of the battery pack, extract the single-cell deviation data to perform 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, determine whether the battery pack is load balanced by calculating the state of charge data of the battery pack. Step S3: when it is determined that the battery pack has load imbalance, the SOC value of each single battery is obtained to evaluate the 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; Step S4: The battery pack operating status data, warning information and vehicle driving status information are sent to the vehicle dashboard for display via wireless communication technology.

[0047] Preferably, 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 further count the frequency of abnormal data occurrence and set a monitoring interval to measure the number of times the monitoring work status data is collected; 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 of the abnormal data occurring in the monitoring interval are obtained. 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.

[0048] Preferably, the specific steps of formulating a 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 to prevent the charging process from continuing. A push notification is sent to the user's mobile phone to issue a load balance warning to remind the user to inspect the vehicle. If the battery pack is in a discharging state, the discharge current of the battery pack will be gradually reduced, and the indicator light on the vehicle dashboard will flash to issue a load balancing warning to remind the user to stop using the vehicle and have it repaired.

[0049] Preferably, 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, and their charging current is increased to speed up the charging speed. 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, and their charging current is reduced to slow down the charging process. 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.

[0050] Preferably, 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.

[0051] Working principle and its effect: A load-balanced new energy battery energy efficiency optimization system and method are designed to improve the performance and safety of new energy batteries and optimize user experience.

[0052] The status monitoring module collects the working status data of the battery pack's single cells, such as voltage, current, and temperature, as well as the vehicle's driving status information in real time, to provide a basis for subsequent analysis. The data analysis module extracts the single cell deviation data by calculating the extreme value difference of the working status data, and compares it with the single cell deviation threshold to determine whether there is a single point of data anomaly and mark the abnormal data. This can promptly detect local anomalies in the battery pack, provide accurate data support for subsequent analysis, and ensure the stable operation of the battery pack.

[0053] After abnormal data is detected, the frequency, duration and interval of abnormal data are counted, and the balance, duration and interval thresholds are combined to determine whether the battery pack is abnormal. If abnormal, the median filter algorithm is used to process the current data, the SOC value of the single battery is calculated according to the ampere-hour integration method, the SOC change rate is calculated by combining the SOC statistical threshold and the sliding window, and the load balance threshold is used to determine whether the battery pack is load balanced. Accurately judge the status of the battery pack and make adjustments in advance to avoid battery performance degradation and shortened life, thereby extending the service life of the battery pack.

[0054] The load balancing module evaluates the load balancing difference level according to the SOC value of the single battery and adopts different strategies. In case of mild imbalance, the simple balancing strategy divides the charging or discharging groups according to the battery pack SOC mean and the set threshold, adjusts the current, and restores the normal current when the range of the battery pack SOC value is less than the stop threshold, which can quickly balance the power, improve the charging efficiency, and avoid overcharging and over-discharging. In case of moderate imbalance, the active balancing strategy marks the single batteries in rich and scarce states, calculates the target charge, formulates an energy transfer plan, dynamically adjusts the balancing value, monitors and adjusts the energy transfer in real time, decides whether to re-balance according to the transfer deviation, monitors the working status data at the same time, warns in abnormal situations, and further optimizes the balance of the battery pack. In case of severe imbalance, the abnormal warning strategy cuts off the power supply during charging and pushes a notification to the user's mobile phone. During discharge, the current is reduced and the dashboard indicator light flashes to remind the user to avoid serious damage to the battery and ensure user safety.

[0055] The communication display module sends the battery pack working status, warning information and vehicle driving status information to the vehicle dashboard via wireless communication, allowing users to understand relevant information in real time, plan their trips reasonably, respond to battery pack problems in a timely manner, and improve user experience.

[0056] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications 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 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 used 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 discharge current of the battery pack will be reduced, and the indicator light on the vehicle dashboard will flash 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 5, characterized in that: 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.

8. A load balancing new energy battery energy efficiency optimization system as claimed in claim 7, 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.

9. A load balancing new energy battery energy efficiency optimization system as claimed in claim 8, 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.

10. 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.

11. 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 10, 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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