Power battery state monitoring and regulation system, method

Abstract

The present invention relates to the field of computer control systems, and specifically to a power battery state monitoring and adjustment system and method, which includes a grouping module for grouping battery cells of a power battery module; a collection module that respectively sets the collection frequencies of current, voltage, and temperature, determines the collection sequence according to the numbers, and performs the collection of current, voltage, and temperature of each battery cell. The current, voltage, and temperature collected in each round respectively form a current matrix, a voltage matrix, and a temperature matrix; an adjustment module that dynamically adjusts the charging power, collection frequency, etc. according to the current, voltage, and temperature data. This method can monitor and dynamically adjust the charging power and temperature of the power battery to improve the battery life and usage safety.

Description

Technical Field

[0001] The present invention relates to the field of computer control systems, and particularly to a power battery state monitoring and regulating system and method. Background Art

[0002] With the rapid growth of the new energy vehicle market, the state management performance of power batteries has become the focus of attention in the industry. In order to ensure the safe and stable operation of power batteries, it is necessary to monitor the voltage, current, and temperature in real time during their charging or discharging states to ensure the balance of charging and discharging and to issue early warnings in a timely manner when the temperature is abnormal, so as to improve the battery service life and usage safety. Summary of the Invention

[0003] The present invention provides a power battery state monitoring and regulating system and method.

[0004] The technical solution of the present invention is as follows:

[0005] A power battery temperature monitoring and regulating system includes the following modules:

[0006] Grouping module: Group the battery cells of the power battery module, preset the number of battery cells in each group. If the total number of battery cells cannot be divided evenly by the preset number, then use the remainder as the number of the last group, and the number of the last group is not less than the quantity threshold, and number each battery cell;

[0007] Acquisition module: When the power battery module is in the charging or discharging state, set the acquisition frequencies of current, voltage, and temperature respectively, determine the acquisition order according to the numbers, and acquire the current, voltage, and temperature of each battery cell. The current, voltage, and temperature acquired in each round respectively form a current matrix, a voltage matrix, and a temperature matrix;

[0008] Regulation module: According to the acquisition time, multiply the corresponding data of the current matrix and the voltage matrix to obtain a power matrix, and calculate the average power by averaging all the powers at the same acquisition moment in the power matrix. If the power battery module is in the charging state, compare the recommended charging power determined according to the historical charging times and the remaining power with the average power. If the value obtained by subtracting the average power from the recommended charging power is positive and greater than the first threshold, then adjust the charging power of the power battery module to the recommended charging power. If the value obtained by subtracting the average power from the recommended charging power is negative and greater than the second threshold, then adjust the charging power of the power battery module to the recommended charging power, and the second threshold is less than the first threshold.

[0009] If there is a situation where the temperature acquired in the current round is greater than or equal to the safety temperature threshold, then start the warning and display the numbers of the battery cells whose temperatures exceed the safety temperature threshold;

[0010] If the temperatures collected in the current round are all less than the safety temperature threshold, a three-dimensional temperature change space curve graph is generated based on the temperature matrix, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safety rate threshold.

[0011] If none of them exceed the safety rate threshold, a state equation of the battery cell is established based on temperature, temperature change rate, and time. According to the state equation and historical data, the temperature at the current moment is predicted. Based on the actual temperature at the current moment, the predicted temperature error covariance matrix and the actual temperature covariance matrix are calculated. The gain coefficient is calculated based on the predicted temperature error covariance matrix and the actual temperature covariance matrix. Using the power battery temperature and the gain coefficient, the predicted value of the power battery temperature and the error covariance matrix at the current moment are updated to predict the temperature of the next round. If the predicted temperature of the next round exceeds the safety temperature threshold, the acquisition frequency of this battery cell is adjusted.

[0012] The specific method for calculating the gain coefficient in the adjustment module is as follows:

[0013] ,

[0014] where, is the gain coefficient, C is the temperature matrix collected, is the covariance matrix of the estimation error, and R is the covariance matrix of the collected temperature noise.

[0015] The specific method for adjusting the temperature acquisition frequency in the adjustment module is as follows:

[0016] The temperature change rate is divided into several intervals, and the temperature acquisition frequency for each interval is preset. The acquisition frequency corresponding to the interval where the temperature change rate of the battery cell exceeding the safety temperature threshold is located is the adjusted acquisition frequency of this battery cell.

[0017] The battery cells exceeding the safety temperature threshold are virtually grouped according to the temperature change rate and assigned to the corresponding intervals, and adjusted using the acquisition frequency of the corresponding intervals.

[0018] The battery cells after the acquisition frequency adjustment are virtually grouped and divided into a high-frequency group, a medium-frequency group, and a low-frequency group according to the adjusted acquisition frequency, and a subsequent temperature matrix is generated based on the frequency grouping.

[0019] The several intervals are specifically as follows:

[0020] Low change interval, the temperature change rate per unit time under the original acquisition frequency is less than 1 degree;

[0021] Medium change interval, the temperature change rate per unit time under the original acquisition frequency is greater than 1 degree and less than 2 degrees;

[0022] High change interval, the temperature change rate per unit time at the original acquisition frequency is greater than 2 degrees.

[0023] The acquisition frequencies corresponding to the intervals are as follows:

[0024] The corresponding frequency for the low change interval is 1 / 2 of the original acquisition frequency;

[0025] The corresponding frequency for the medium change interval is 1 / 5 of the original acquisition frequency;

[0026] The corresponding frequency for the high change interval is 1 / 10 of the original acquisition frequency.

[0027] Calculate the theoretical temperature change rate of the power battery cell according to the Fourier thermodynamics formula. If the temperature change rate of the battery cell exceeds the theoretical temperature change rate of the power battery cell, key monitoring is carried out and it is classified into the high change interval.

[0028] Generate a three-dimensional temperature change space curve graph, which is a multi-parallel operation. Based on the battery cells, simultaneously draw a three-dimensional temperature change space curve graph of the power battery. The three coordinates are the group number, the temperature of the battery cell, and the time. A method for monitoring and adjusting the state of a power battery includes:

[0029] S1: Group the battery cells of the power battery module, preset the number of battery cells in each group. If the total number of battery cells cannot be divided evenly by the preset number, then use the remainder as the number of the last group, and the number of the last group is not less than the quantity threshold. Number each battery cell;

[0030] S2: When the power battery module is in the charging or discharging state, set the acquisition frequencies of current, voltage, and temperature respectively, determine the acquisition order according to the number, and perform the acquisition of current, voltage, and temperature of each battery cell. The current, voltage, and temperature acquired in each round respectively form a current matrix, a voltage matrix, and a temperature matrix;

[0031] S3: According to the acquisition time, multiply the corresponding data of the current matrix and the voltage matrix to obtain a power matrix, calculate the average value of all powers at the same acquisition moment in the power matrix to obtain the average power. If the power battery module is in the charging state, compare the recommended charging power determined according to the historical charging times and the remaining power with the average power. If the value obtained by subtracting the average power from the recommended charging power is positive and greater than the first threshold, adjust the charging power of the power battery module to the recommended charging power. If the value obtained by subtracting the average power from the recommended charging power is negative and greater than the second threshold, adjust the charging power of the power battery module to the recommended charging power. The second threshold is less than the first threshold.

[0032] If there is a situation where the temperature collected in the current round is greater than or equal to the safety temperature threshold, start an alarm and display the numbers of the battery cells whose temperatures exceed the safety temperature threshold.

[0033] If the temperatures collected in the current round are all less than the safety temperature threshold, then based on the temperature matrix, a three-dimensional temperature change space curve graph is generated, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safety rate threshold.

[0034] If none of them exceed the safety rate threshold, then based on the temperature, temperature change rate, and time, a battery cell state equation is established. According to the state equation and historical data, the temperature at the current moment is predicted. Based on the actual temperature at the current moment, the predicted temperature error covariance matrix and the actual temperature covariance matrix are calculated. The gain coefficient is calculated based on the predicted temperature error covariance matrix and the actual temperature covariance matrix. Using the power battery temperature and the gain coefficient, the predicted value of the power battery temperature and the error covariance matrix at the current moment are updated to predict the temperature of the next round. If the predicted temperature of the next round exceeds the safety temperature threshold, the acquisition frequency of the battery cell is adjusted. Detailed implementation manner

[0035] The technical solution of the present invention is as follows:

[0036] A power battery state monitoring and regulating system includes the following modules:

[0037] Grouping module: Group the battery cells of the power battery module, preset the number of battery cells in each group. If the total number of battery cells cannot be divided evenly by the preset number, then take the remainder as the number of the last group, and the number of the last group is not less than the number threshold, and number each battery cell.

[0038] The specific method for grouping battery cells in the grouping module is as follows:

[0039] Preset the number of battery cells in each group to be 5 or 6, and preferentially select the preset number that the total number of battery cells can be divided evenly by.

[0040] If the total number of battery cells can be divided evenly by both preset numbers, then select the preset number as 6.

[0041] If the total number of battery cells cannot be divided evenly by one of the two preset numbers, then select the preset number with the larger remainder.

[0042] If the total number of battery cells cannot be divided evenly by one of the two preset numbers and the obtained remainders are the same, then select the preset number as 6.

[0043] In a power battery pack, the deployment of temperature sensors is a crucial step. These sensors are embedded between battery cells or on the surface of battery modules to accurately measure the temperature of each battery cell or module. The type and quantity of sensors depend on the scale of the battery pack, the design complexity, and the monitoring requirements. For a large-scale battery pack with oversized battery cells, multiple high-precision temperature sensors are required for each battery cell to ensure coverage of all critical areas.

[0044] Acquisition module: When the power battery module is in the charging or discharging state, set the acquisition frequencies of current, voltage, and temperature respectively, determine the acquisition order according to the numbering, and acquire the current, voltage, and temperature of each battery cell. The current, voltage, and temperature acquired in each round respectively form a current matrix, a voltage matrix, and a temperature matrix.

[0045] Preferably, temperature sensors can be set between two battery cells in a group in the acquisition module to save costs.

[0046] Further preferably, the state management of the power battery module needs to be carried out when it is in the charging or discharging state. This is because in these two states, chemical reactions occur inside the battery cells, generating heat and causing temperature changes. To accurately capture such temperature changes, reasonable acquisition frequencies of current, voltage, and temperature need to be set. The setting of the acquisition frequency comprehensively considers factors such as the thermal response time of the battery cells, the performance of the heat dissipation system, and the accuracy of the temperature monitoring system.

[0047] When the power battery module is in the charging or discharging state, a temperature acquisition frequency of 1 minute / time needs to be set. The setting of the acquisition frequency should be determined according to the characteristics and application scenarios of the power battery to ensure that the details of temperature changes can be accurately captured. Generally speaking, the higher the acquisition frequency, the more accurate the acquired temperature data, but it will also increase the difficulty and computational amount of data processing.

[0048] Determine that the acquisition and data storage order corresponds to the numbering. According to the numbering order of the battery cells, determine the acquisition order of current, voltage, and temperature. During the acquisition process, ensure that the current, voltage, and temperature data of each battery cell can be accurately recorded, and associate the acquired current, voltage, and temperature data with the corresponding battery cell number for subsequent analysis and processing.

[0049] After acquiring the current, voltage, and temperature data, during each round of acquisition process, sequentially acquire the current, voltage, and temperature data of each battery cell according to the determined acquisition order. Arrange the acquired current, voltage, and temperature data according to the time point and battery cell number to form multiple two-dimensional arrays, that is, obtain the current matrix, voltage matrix, and temperature matrix respectively.

[0050] Each row of the matrix represents the current, voltage, and temperature data at a time point, and each column represents the current, voltage, and temperature data of a single battery cell.

[0051] Adjustment module: According to the acquisition time, multiply the corresponding data of the current matrix and the voltage matrix to obtain the power matrix. Calculate the average power by averaging all the powers at the same acquisition moment in the power matrix. If the power battery module is in the charging state, compare the recommended charging power determined according to the historical charging times and the remaining power with the average power. If the value obtained by subtracting the average power from the recommended charging power is positive and greater than the first threshold, adjust the charging power of the power battery module to the recommended charging power. If the value obtained by subtracting the average power from the recommended charging power is negative and greater than the second threshold, adjust the charging power of the power battery module to the recommended charging power. The second threshold is less than the first threshold.

[0052] If there is a situation where the temperature collected in the current round is greater than or equal to the safety temperature threshold, start the warning and display the serial number of the battery cell whose temperature exceeds the safety temperature threshold.

[0053] If the temperatures collected in the current round are all less than the safety temperature threshold, generate a three-dimensional temperature change space curve graph based on the temperature matrix, calculate the temperature change rate, and determine whether the temperature change rate of each battery cell exceeds the safety rate threshold.

[0054] If none of them exceed the safety rate threshold, establish a state equation of the battery cell based on the temperature, temperature change rate, and time. According to the state equation and historical data, predict the temperature at the current moment. Based on the actual temperature at the current moment, calculate the predicted temperature error covariance matrix and the actual temperature covariance matrix. Calculate the gain coefficient according to the predicted temperature error covariance matrix and the actual temperature covariance matrix. Use the power battery temperature and the gain coefficient to update the predicted value of the power battery temperature and the error covariance matrix at the current moment, and predict the temperature of the next round. If the predicted temperature of the next round exceeds the safety temperature threshold, adjust the acquisition frequency of this battery cell.

[0055] Generally, the manufacturer of the power battery module will give suggestions or notifications on the charging power according to the battery model, etc. With the continuous update of power battery technology, there have also been situations where the charging power is recommended according to the historical charging times and the recommended charging power is determined according to the remaining power. Therefore, there is a recommended charging power for reference every time of charging. If the recommended charging powers determined according to factors such as historical charging times and remaining power are different, take the smallest value among them as the recommended charging power.

[0056] In the adjustment module, a three-dimensional spatial curve graph of temperature change is generated. For multiple parallel operations, based on battery cells, a three-dimensional spatial curve graph of temperature change is drawn simultaneously. The three coordinates are the grouping serial number, the temperature of the battery cell, and time. The time axis can be used as the frame of the animation, and the spatial axis represents the position of the battery cell in the battery pack. The temperature value is represented by color or height.

[0057] Use Python's Matplotlib or professional data visualization software to generate a three-dimensional spatial curve graph of temperature change. These tools support dynamic display, and the change of temperature over time and space can be intuitively seen.

[0058] During the entire temperature data processing process, temperature data quality control is crucial. This includes regularly checking the status of sensors, calibrating temperature data, verifying the accuracy and integrity of temperature data. In addition, a temperature data quality monitoring mechanism should be established to promptly detect and handle problems in temperature data.

[0059] The state equation of the battery cell constructed in the adjustment module is:

[0060] To establish the state equation of the battery cell, we need to consider three variables: temperature, temperature change rate, and time. The state of the battery can include its health state, performance state, etc. However, here, we mainly focus on the impact of temperature on the battery state.

[0061] Assume that the temperature state of the battery can be represented by a function of time t, that is, T(t). According to Fourier's thermodynamics formula, the temperature change rate is deduced, that is ,

[0062] The temperature change of the battery is affected by an internal heat source, that is, the chemical reaction inside the battery, and an external heat source. At the same time, the battery exchanges heat with the outside world through heat conduction and heat radiation. Combining these factors, a simplified state equation is obtained: ,

[0063] Among them, C is the heat capacity of the battery, indicating the ability of the battery to store thermal energy; is the heat generated inside the battery; is the heat dissipated by the battery through heat conduction, heat radiation, etc.

[0064] For further simplification, assume and are both functions of T(t) and t, or can be regarded as constants or linearly varying with time in some cases.

[0065] ,

[0066] Among them, I is the charge and discharge current,R is the internal resistance of the power battery.

[0067] ,

[0068] Among them, h is the heat dissipation coefficient, T is the battery temperature, is the ambient temperature.

[0069] Assume that a deterministic discrete-time system can be described by the following state-space equation:

[0070] ,

[0071] ,

[0072] Among them, the subscript represents the sampling time, is the temperature to be estimated at time t+1, is the temperature to be estimated at time t, A is the state transition matrix, B is the control matrix, C is the observation transition matrix, is the control input at time t, is the actual temperature at time t.

[0073] Introduce process disturbance and measurement noise , then the above state-space equation is expressed as:

[0074] ,

[0075] ,

[0076] Output the actual temperature at time t , so an estimate of the state is calculated by back-calculating with the measured value:

[0077] ,

[0078] Among them, is the unbiased estimated temperature, and another estimate of the state is obtained by recursion using the previous result:

[0079] ,

[0080] Among them, is the predicted temperature, is the predicted temperature at time t-1, is the control input at time t-1.

[0081] Then the estimate of the temperature state is: ,

[0082] Among them, G is the total gain value;

[0083] Further transform the above formula. Let ,

[0084] ,

[0085] Among them, is the gain coefficient;

[0086] Measures the gap between the estimated value and the true value, that is, the error is:

[0087]

[0088] ,

[0089] Among them, I is the conversion value, I = A + B.

[0090] The smaller the error between the estimated value and the true value, the better. That is, the smaller the variance of the error normal distribution satisfied by the error, the better. It is transformed into the minimum covariance of the error.

[0091] Denote the covariance matrix of the estimation error as , where E is the expectation,

[0092] Introduce the derivative formula to get:

[0093] ,

[0094] Substitute back into That is the estimated temperature of the power battery.

[0095] Among them, is the gain coefficient, C is the collected temperature matrix, is the covariance matrix of the estimation error, and R is the covariance matrix of the collected temperature noise.

[0096] The specific method for adjusting the temperature acquisition frequency in the adjustment module is,

[0097] Divide the temperature change rate into several intervals, preset the temperature acquisition frequency for each interval, and the acquisition frequency corresponding to the interval where the temperature change rate of the battery cell exceeds the safety temperature threshold is the acquisition frequency adjusted for this battery cell.

[0098] Virtual group the battery cells that exceed the safety temperature threshold according to the temperature change rate, divide them into the corresponding intervals, and adjust them using the acquisition frequency of the corresponding intervals.

[0099] Virtual group the battery cells after adjusting the acquisition frequency, and divide them into a high-frequency group, a medium-frequency group, and a low-frequency group according to the adjusted acquisition frequency, and generate the subsequent temperature matrix based on the frequency grouping.

[0100] The adjustment of the acquisition frequency is real-time and dynamic. If the temperature change rate calculated based on the measured temperature data of the battery cells in the high-frequency group decreases within a certain time range and falls into another interval, while adjusting the acquisition frequency, this battery cell is transferred to the corresponding acquisition frequency group, so as to realize the adaptive regulation of the acquisition frequency and grouping, and achieve the purpose of balancing the relationship between the acquisition frequency and data processing.

[0101] Several intervals can be specifically divided according to the following rules:

[0102] Low change interval: The temperature change rate per unit time under the original acquisition frequency is less than 1 degree;

[0103] Medium change interval: The temperature change rate per unit time under the original acquisition frequency is greater than 1 degree and less than 2 degrees;

[0104] High change interval: The temperature change rate per unit time under the original acquisition frequency is greater than 2 degrees.

[0105] The acquisition frequencies corresponding to the intervals are as follows.

[0106] The corresponding frequency for the low change interval is 1 / 2 of the original acquisition frequency;

[0107] The corresponding frequency for the medium change interval is 1 / 5 of the original acquisition frequency;

[0108] The corresponding frequency for the high change interval is 1 / 10 of the original acquisition frequency.

[0109] If the temperature change rate of the battery cell exceeds the theoretical temperature change rate of the power battery cell, it will be key monitored and classified into the high change interval.

[0110] The abnormal battery temperature may be caused by the quality of the battery itself, or may be caused by problems such as charge and discharge power or welding process. This application further monitors the temperature in order to be able to locate the cause of the temperature rise and provide a reference solution for subsequent processing methods.

[0111] If there is a situation where the temperature collected in the current round in the adjustment module is greater than or equal to the safety temperature threshold, an alarm is started, and the battery cell number with the temperature exceeding the safety temperature threshold is displayed. Since the setting of the safety temperature threshold is lower than the dangerous temperature (the risk of spontaneous combustion and other dangers is relatively high when working at this temperature), so if the collected temperature is greater than or equal to the safety temperature threshold, it is still possible to continue working. At this time, it is necessary to continue to monitor the temperature of this numbered battery cell, and it is necessary to adjust the temperature acquisition frequency to the preset maximum acquisition frequency for acquisition, so as to be able to make corresponding measures more quickly and avoid danger.

[0112] If the power battery module is in a charging state, while continuing to collect the temperature, compare the temperature of this battery cell with the temperatures of other battery cells in the power battery module.

[0113] Since the collection frequencies may be different, when making the comparison, select the temperature for comparison through the following reference ideas:

[0114] a. If the collection frequency of this battery cell can divide the collection frequency of the battery cell to be compared, then compare the temperature of this battery cell collected at the same collection moment as the battery cell to be compared with the temperature of the battery cell to be compared.

[0115] b. If the collection frequency of this battery cell cannot divide the collection frequency of the battery cell to be compared, then compare the temperature of this battery cell collected at the latest collection moment with the temperature of the battery cell to be compared collected at the latest collection moment.

[0116] If, within a preset time period, the temperature difference between this battery cell and the temperatures of other battery cells in the power battery module is within the first difference range, it indicates that the temperatures of other battery cells are also rising. It is judged that the temperature rise may be caused by the charging power or the charging device, and a prompt to adjust the charging power and check the charging device is given. The charging power is adjusted in the direction of reducing the charging power. For the first adjustment, a large range of values can be adjusted. If a maximum power reduction value is preset, during the first adjustment, the charging power is reduced by a maximum power reduction value.

[0117] If, within a preset time period, the temperature difference between this battery cell and the temperatures of other battery cells in the power battery module is greater than the second difference, and the second difference is greater than the first difference, it indicates that the temperature rise of this battery cell compared with other battery cells is abnormal. It is judged that there may be a problem with the battery cell itself, such as a cell problem or battery welding process, etc., and a prompt that there may be a problem with this battery cell is given.

[0118] Of course, the above judgments on the causes of battery temperature rise and the given prompts are only for reference, rather than the final overhaul conclusion.

[0119] The present invention also provides a method for monitoring and regulating the state of a power battery, including the following steps:

[0120] S1: Group the battery cells of the power battery module, preset the number of battery cells in each group. If the total number of battery cells cannot divide the preset number, then use the remainder as the number of the last group, and the number of the last group is not less than the number threshold, and number each battery cell.

[0121] S2: When the power battery module is in the charging or discharging state, set the acquisition frequencies of current, voltage, and temperature respectively, determine the acquisition order according to the numbers, and acquire the current, voltage, and temperature of each battery cell. The current, voltage, and temperature acquired in each round respectively form a current matrix, a voltage matrix, and a temperature matrix;

[0122] S3: According to the acquisition time, multiply the corresponding data of the current matrix and the voltage matrix to obtain a power matrix. Calculate the average power by averaging all the powers at the same acquisition moment in the power matrix. If the power battery module is in the charging state, compare the recommended charging power determined according to the historical charging times and the remaining power with the average power. If the value obtained by subtracting the average power from the recommended charging power is positive and greater than the first threshold, adjust the charging power of the power battery module to the recommended charging power. If the value obtained by subtracting the average power from the recommended charging power is negative and greater than the second threshold, adjust the charging power of the power battery module to the recommended charging power. The second threshold is less than the first threshold.

[0123] If there is a situation where the temperature acquired in the current round is greater than or equal to the safety temperature threshold, start an alarm and display the numbers of the battery cells whose temperatures exceed the safety temperature threshold;

[0124] If the temperatures acquired in the current round are all less than the safety temperature threshold, generate a three-dimensional temperature change space curve graph based on the temperature matrix, calculate the temperature change rate, and judge whether the temperature change rate of each battery cell exceeds the safety rate threshold.

[0125] If none of them exceed the safety rate threshold, establish a battery cell state equation based on the temperature, temperature change rate, and time. According to the state equation and historical data, predict the temperature at the current moment. According to the actual temperature at the current moment, calculate the predicted temperature error covariance matrix and the actual temperature covariance matrix. Calculate the gain coefficient according to the predicted temperature error covariance matrix and the actual temperature covariance matrix. Use the power battery temperature and the gain coefficient to update the predicted value of the power battery temperature and the error covariance matrix at the current moment, and predict the temperature of the next round. If the predicted temperature of the next round exceeds the safety temperature threshold, adjust the acquisition frequency of this battery cell.

Claims

1. A power battery status monitoring and adjustment system, characterized in that: The steps include: Grouping module: group the battery cells of the power battery module, preset the number of battery cells in each group, and if the total number of battery cells cannot divide the preset number, take the remainder as the number of the last group, and the number of the last group is not less than the number threshold, and number each battery cell; Collection module: When the power battery module is in the charging or discharging state, the collection frequency of current, voltage and temperature is set respectively, and the collection order is determined according to the number to collect the current, voltage and temperature of each battery cell. The current, voltage and temperature collected in each round form the current matrix, voltage matrix and temperature matrix respectively; Adjustment module: According to the acquisition time, the corresponding data of the current matrix and the voltage matrix are multiplied to obtain the power matrix, and the average power is obtained by averaging all the powers at the same acquisition time in the power matrix. If the power battery module is in a charging state, the recommended charging power determined according to the historical charging times and the remaining power is compared with the average power. If the value of the recommended charging power minus the average power is positive and greater than the first threshold, the charging power of the power battery module is adjusted to the recommended charging power. If the value of the recommended charging power minus the average power is negative and greater than the second threshold, the charging power of the power battery module is adjusted to the recommended charging power. The second threshold is less than the first threshold. If the temperature collected in the current round is greater than or equal to the safety temperature threshold, an early warning is initiated, and the battery cell number whose temperature exceeds the safety temperature threshold is displayed; If the temperatures collected in the current round are all lower than the safe temperature threshold, a three-dimensional temperature change space curve is generated based on the temperature matrix, and the temperature change rate is calculated to determine whether the temperature change rate of each battery cell exceeds the safe rate threshold. If the safety rate threshold is not exceeded, a battery cell state equation is established based on the temperature, temperature change rate and time. The temperature at the current moment is predicted based on the state equation and historical data. The predicted temperature error covariance matrix and the actual temperature covariance matrix are calculated based on the actual temperature at the current moment. The gain coefficient is calculated based on the predicted temperature error covariance matrix and the actual temperature covariance matrix. The power battery temperature and the gain coefficient are used to update the power battery temperature prediction value and the error covariance matrix at the current moment to predict the temperature of the next round. If the predicted temperature of the next round exceeds the safe temperature threshold, the collection frequency of the battery cell is adjusted; In the regulation module, if the temperature collected in the current round is greater than or equal to the safety temperature threshold, an early warning is initiated, and the battery cell number whose temperature exceeds the safety temperature threshold is displayed, and the temperature collection frequency is adjusted to the preset maximum collection frequency for collection; If the power battery module is in a charging state, the temperature of the battery cell is compared with the temperatures of other battery cells in the power battery module while continuing to collect temperature; Since the acquisition frequency may be different, when making a comparison, the temperature for comparison is selected in the following way: a. If the acquisition frequency of the battery cell can be divided by the acquisition frequency of the battery cell to be compared, the temperature of the battery cell to be compared and the temperature of the battery cell to be compared collected at the same time as the acquisition time of the battery cell to be compared are compared; b. If the acquisition frequency of the battery cell cannot be divided evenly by the acquisition frequency of the battery cell to be compared, the temperature of the battery cell acquired at the latest acquisition time is compared with the temperature of the battery cell to be compared at the latest acquisition time; If the temperature difference between the battery cell and the temperature of other battery cells in the power battery module is within the first difference range within the preset time period, a prompt to adjust the charging power and check the charging equipment is given; If within a preset time period, the temperature difference between this battery cell and the temperature of other battery cells in the power battery module is greater than the second difference, and the second difference is greater than the first difference, a prompt is given that there is a problem with this battery cell.

2. A power battery status monitoring and adjustment system according to claim 1, characterized in that: The gain coefficient calculation method in the adjustment module is specifically as follows: ， in, is the gain coefficient, C is the collected temperature matrix, is the covariance matrix of the estimation error, and R is the covariance matrix of the acquisition temperature noise.

3. A power battery status monitoring and adjustment system according to claim 1, characterized in that: The specific method of adjusting the acquisition frequency in the adjustment module is: The temperature change rate is divided into several intervals, and the temperature collection frequency corresponding to each interval is preset. The collection frequency corresponding to the interval where the temperature change rate of the battery cell whose predicted temperature exceeds the safety temperature threshold in the next round is located is used as the adjusted collection frequency of the battery cell. According to the adjustment of the acquisition frequency, the battery cells are regrouped, and the battery cells with the same acquisition frequency are divided into the same group. The adjusted acquisition frequency is used for temperature acquisition. The battery cells that exceed the safety temperature threshold are virtually grouped according to the temperature change rate and divided into corresponding intervals. The acquisition frequency of the corresponding interval is adjusted, and the battery cells after the acquisition frequency adjustment are virtually grouped and divided into high-frequency group, medium-frequency group and low-frequency group according to the adjusted acquisition frequency. The subsequent temperature matrix is ​​generated based on the frequency grouping. If the temperature change rate of the battery cell in the high-frequency group calculated according to the measured temperature data decreases within a certain time range and falls into another interval, the acquisition frequency is adjusted while adjusting the battery cell to the corresponding acquisition frequency grouping.

4. A power battery status monitoring and adjustment system according to claim 3, characterized in that: The several intervals are specifically: In the low change range, the temperature change rate per unit time under the original acquisition frequency is less than or equal to 1 degree; In the medium change range, the temperature change rate per unit time under the original acquisition frequency is greater than 1 degree and less than 2 degrees; In the high change range, the temperature change rate per unit time under the original acquisition frequency is greater than or equal to 2 degrees.

5. A power battery status monitoring and regulating system according to claim 4, characterized in that: The acquisition frequency of the interval corresponds to: The corresponding frequency of the low-variation interval is 1 / 2 of the original acquisition frequency; The corresponding frequency of the medium change interval is 1 / 5 of the original acquisition frequency; The corresponding frequency of the high change interval is 1 / 10 of the original acquisition frequency.

6. A power battery status monitoring and regulating system according to any one of claims 3 to 5, characterized in that: The theoretical power battery cell temperature change rate is calculated according to the Fourier thermodynamics formula. If the battery cell temperature change rate exceeds the theoretical power battery cell temperature change rate, it is monitored closely and classified into the high change range.

7. A power battery status monitoring and adjustment system according to claim 1, characterized in that: The generating of the three-dimensional temperature variation space curve graph is a plurality of parallel operations, and based on the battery cells, a three-dimensional power battery temperature variation space curve graph is simultaneously drawn, and the three coordinates are the battery cell number, the battery cell temperature and the acquisition time.

8. A method for monitoring and adjusting the state of a power battery, characterized in that: include: S1: Grouping the battery cells of the power battery module, presetting the number of battery cells in each group, and if the total number of battery cells cannot divide the preset number, taking the remainder as the number of the last group, and the number of the last group is not less than the number threshold, numbering each battery cell; The temperature acquisition module sets the temperature acquisition frequency when the power battery module is in the charging or discharging state, determines the acquisition order according to the number, and collects the temperature of each battery cell. The temperatures collected in each round form a temperature matrix. S2: When the power battery module is in the charging or discharging state, the collection frequency of current, voltage and temperature is set respectively, and the collection order is determined according to the number, and the current, voltage and temperature of each battery cell are collected. The current, voltage and temperature collected in each round form a current matrix, a voltage matrix and a temperature matrix respectively; S3: According to the acquisition time, the corresponding data of the current matrix and the voltage matrix are multiplied to obtain the power matrix, and the average power is obtained by averaging all the powers at the same acquisition time in the power matrix. If the power battery module is in a charging state, the recommended charging power determined according to the historical charging times and the remaining power is compared with the average power. If the value of the recommended charging power minus the average power is positive and greater than a first threshold, the charging power of the power battery module is adjusted to the recommended charging power. If the value of the recommended charging power minus the average power is negative and greater than a second threshold, the charging power of the power battery module is adjusted to the recommended charging power. The second threshold is less than the first threshold. If the temperature collected in the current round is greater than or equal to the safety temperature threshold, an early warning is initiated and the battery cell number whose temperature exceeds the safety temperature threshold is displayed; If the temperatures collected in the current round are all lower than the safe temperature threshold, a three-dimensional temperature change space curve is generated based on the temperature matrix, and the temperature change rate is calculated to determine whether the temperature change rate of each battery cell exceeds the safe rate threshold. If the safety rate threshold is not exceeded, a battery cell state equation is established based on the temperature, temperature change rate and time. The temperature at the current moment is predicted based on the state equation and historical data. The predicted temperature error covariance matrix and the actual temperature covariance matrix are calculated based on the actual temperature at the current moment. The gain coefficient is calculated based on the predicted temperature error covariance matrix and the actual temperature covariance matrix. The power battery temperature and the gain coefficient are used to update the power battery temperature prediction value and the error covariance matrix at the current moment to predict the temperature of the next round. If the predicted temperature of the next round exceeds the safe temperature threshold, the collection frequency of the battery cell is adjusted; In the regulation module, if the temperature collected in the current round is greater than or equal to the safety temperature threshold, an early warning is initiated, and the battery cell number whose temperature exceeds the safety temperature threshold is displayed, and the temperature collection frequency is adjusted to the preset maximum collection frequency for collection; If the power battery module is in a charging state, the temperature of the battery cell is compared with the temperatures of other battery cells in the power battery module while continuing to collect temperature; Since the acquisition frequency may be different, when making a comparison, the temperature for comparison is selected in the following way: a. If the acquisition frequency of the battery cell can be divided by the acquisition frequency of the battery cell to be compared, the temperature of the battery cell to be compared and the temperature of the battery cell to be compared collected at the same time as the acquisition time of the battery cell to be compared are compared; b. If the acquisition frequency of the battery cell cannot be divided evenly by the acquisition frequency of the battery cell to be compared, the temperature of the battery cell acquired at the latest acquisition time is compared with the temperature of the battery cell to be compared at the latest acquisition time; If the temperature difference between the battery cell and the temperature of other battery cells in the power battery module is within the first difference range within the preset time period, a prompt to adjust the charging power and check the charging equipment is given; If within a preset time period, the temperature difference between this battery cell and the temperature of other battery cells in the power battery module is greater than the second difference, and the second difference is greater than the first difference, a prompt is given that there is a problem with this battery cell.

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