Power battery state monitoring and adjusting system and method

Abstract

The invention relates to the field of computer control systems, in particular to a power battery state monitoring and adjusting system and method, and the system comprises a grouping module which carries out the grouping of single batteries of a power battery module; the acquisition module is used for respectively setting acquisition frequencies of current, voltage and temperature, determining an acquisition sequence according to serial numbers and acquiring the current, the voltage and the temperature of each single battery, and the current, the voltage and the temperature acquired in each turn respectively form a current matrix, a voltage matrix and a temperature matrix; and the adjusting module is used for dynamically adjusting the charging power, the acquisition frequency and the like according to the current, voltage and temperature data. The method can monitor and dynamically adjust the charging power and temperature of the power battery so as to prolong the service life of the battery and improve the use safety of the battery.

Description

Technical Field

[0001] The present invention relates to the field of computer control systems, and in particular 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 the industry. In order to ensure the safe and stable operation of power batteries, it is necessary to monitor the voltage, current and temperature of the batteries in real time during charging or discharging to ensure the balance of charging and discharging and to issue early warnings in time when the temperature is abnormal, so as to improve the battery life and safety. Summary of the invention

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

[0004] The technical solution of the present invention is as follows: A power battery temperature monitoring and regulation system includes the following modules: 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, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safe rate threshold. If neither exceeds the safety rate threshold, a battery cell state equation is established based on 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 current power battery temperature prediction value and the error covariance matrix to predict the next round of temperature. If the predicted temperature of the next round exceeds the safety temperature threshold, the collection frequency of the battery cell is adjusted.

[0005] The calculation method of gain coefficient in the adjustment module is 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.

[0006] The specific method for adjusting the temperature acquisition frequency in the regulation module is: The temperature change rate is divided into several intervals, and the temperature collection frequency of each interval is preset. The collection frequency corresponding to the interval where the temperature change rate of the battery cell exceeding the safety temperature threshold is located is the collection frequency adjusted for the battery cell. The battery cells that exceed the safety temperature threshold are virtually grouped according to the temperature change rate, divided into corresponding intervals, and the collection frequency of the corresponding intervals is adjusted; The battery cells after the acquisition frequency adjustment are virtually grouped 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.

[0007] The specific intervals are: In the low change range, the temperature change rate per unit time is less than 1 degree at the original acquisition frequency; 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 2 degrees.

[0008] The sampling 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.

[0009] 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.

[0010] Generate a three-dimensional temperature change space curve graph, which is a multiple parallel operation. Based on the battery cell, a three-dimensional power battery temperature change space curve graph is drawn at the same time. The three coordinates are the group number, the battery cell temperature and the time. A power battery state monitoring and adjustment method includes: 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; 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, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safe rate threshold. If neither exceeds the safety rate threshold, a battery cell state equation is established based on 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 current power battery temperature prediction value and the error covariance matrix to predict the next round of temperature. If the predicted temperature of the next round exceeds the safety temperature threshold, the collection frequency of the battery cell is adjusted. DETAILED DESCRIPTION

[0011] The technical solution of the present invention is as follows: A power battery status monitoring and regulation system includes the following modules: 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; The specific method of grouping battery cells in the grouping module is: The number of battery cells in each group is preset to 5 or 6, preferably the preset number that can be divided by the total number of battery cells; If the total number of battery cells can divide two preset numbers, the preset number is selected as 6; If the total number of battery cells cannot divide one of the two preset numbers, the preset number with the larger remainder is selected; If the total number of battery cells cannot be divided evenly into one of the two preset numbers, and the remainders obtained are the same, the preset number is selected as 6.

[0012] The deployment of temperature sensors in power battery packs is a key 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 number of sensors depend on the size of the battery pack, the complexity of the design, and the monitoring requirements. If a large battery pack is used and the battery cells are too large, multiple high-precision temperature sensors are required for each battery cell to ensure that all critical areas are covered.

[0013] 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; Preferably, a temperature sensor may be provided between two battery cells in a group in the acquisition module to save costs.

[0014] As a further preference, the state management of the power battery module needs to be carried out in its charging or discharging state. This is because in these two states, chemical reactions will occur inside the battery cells, generating heat and causing temperature changes. In order to accurately capture this temperature change, it is necessary to set reasonable current, voltage and temperature acquisition frequencies. 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.

[0015] When the power battery module is in the charging or discharging state, the temperature collection frequency needs to be set to 1min / time. The setting of the collection frequency should be determined according to the characteristics of the power battery and the application scenario to ensure that the details of the temperature changes can be accurately captured. Generally speaking, the higher the collection frequency, the more accurate the temperature data obtained, but it will also increase the difficulty and calculation amount of data processing.

[0016] Determine the order of collection and data storage corresponding to the number, and determine the order of current, voltage, and temperature collection according to the numbering order of the battery cells. During the collection process, ensure that the current, voltage, and temperature data of each battery cell can be accurately recorded, and associate the collected current, voltage, and temperature data with the corresponding battery cell number for subsequent analysis and processing.

[0017] After collecting the current, voltage and temperature data, in each round of collection, the current, voltage and temperature data of each battery cell are collected in sequence according to the determined collection order. The collected current, voltage and temperature data are arranged according to the time point and the battery cell number to form multiple two-dimensional arrays, that is, the current matrix, voltage matrix and temperature matrix are obtained respectively.

[0018] 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 battery cell.

[0019] 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, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safe rate threshold. If neither exceeds the safety rate threshold, a battery cell state equation is established based on 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 current power battery temperature prediction value and the error covariance matrix to predict the next round of temperature. If the predicted temperature of the next round exceeds the safety temperature threshold, the collection frequency of the battery cell is adjusted.

[0020] Usually, the manufacturer of power battery modules will give charging power recommendations or notifications based on the battery model, etc. With the continuous updating of power battery technology, there are also situations where charging power recommendations are made based on the number of historical charging times, and the recommended charging power is determined based on the remaining power. Therefore, every time charging is performed, there will be a recommended charging power for reference. If the recommended charging power determined based on factors such as the number of historical charging times and the remaining power is different, take the smallest value as the recommended charging power.

[0021] A three-dimensional temperature change spatial curve graph is generated in the adjustment module. It is a multiple parallel operation. Based on the battery cells, a three-dimensional temperature change spatial curve graph is drawn simultaneously. The three coordinates are the group number, battery cell temperature and time. The time axis can be used as an animation frame, the space axis represents the position of the battery cell in the battery pack, and the temperature value is represented by color or height.

[0022] Use Python's Matplotlib or professional data visualization software to generate a three-dimensional temperature change spatial curve graph. These tools support dynamic display, which allows you to intuitively see the changes in temperature over time and space.

[0023] Temperature data quality control is critical throughout the entire temperature data processing process. This includes regularly checking the status of sensors, calibrating temperature data, and 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.

[0024] The battery cell state equation constructed in the regulation module is: In order to establish the state equation of a battery cell, we need to consider three variables: temperature, temperature change rate, and time. The state of a battery can include its health state, performance state, etc., but here, we mainly focus on the impact of temperature on the battery state.

[0025] Assuming that the temperature state of the battery can be expressed as a function of time t, that is, T(t), the temperature change rate is derived according to the Fourier thermodynamics formula, that is, , 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 also exchanges heat with the outside world through heat conduction and thermal radiation. Combining these factors, a simplified state equation is obtained: , Where C is the thermal capacity of the battery, which represents the battery's ability to store thermal energy; It is the heat generated inside the battery; It is the heat dissipated by the battery through heat conduction, thermal radiation, etc.

[0026] To simplify further, assume and are all functions of T(t) and t, or in some cases can be considered constant or vary linearly with time.

[0027] , in, I is the charge and discharge current, R It is the internal resistance of the power battery.

[0028] ,

[0029] in, h is the heat dissipation coefficient, T is the battery temperature, is the ambient temperature.

[0030] Assume that a deterministic discrete-time system can be described by the following state-space equations: , , The subscripts represent the sampling time. is the estimated temperature at time t+1, is the estimated temperature at time t, A is the state transfer matrix, B is the control matrix, C is the observation transfer matrix, is the control input at time t, is the actual temperature at time t.

[0031] Introducing process disturbances and measurement noise , then the above state space equation is expressed as: , , Output the actual temperature at time t , so one estimate of the state is to back-calculate it from the measured value: , in, is an unbiased estimate of the temperature. Another estimate of the state is to use the previous result recursively: , in, is the predicted temperature, is the predicted temperature at time t-1, is the control input at time t-1.

[0032] The estimate of the temperature state is: , Where G is the total gain; Further transform the above formula, let , , in, is the gain coefficient; Measures the difference between the estimated value and the true value, i.e., the error for:

[0033] ,

[0034] Among them, I is the conversion value, I=A+B.

[0035] The smaller the error between the estimated value and the true value, the better. In other words, the smaller the variance of the error normal distribution that the error satisfies, the better, which converts into the smallest covariance of the error.

[0036] The covariance matrix of the estimation error is recorded as , where E is the expectation, Introducing the derivative formula, we get: , Substitution This is the estimated power battery temperature.

[0037] 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.

[0038] The specific method for adjusting the temperature acquisition frequency in the regulation module is: The temperature change rate is divided into several intervals, and the temperature collection frequency of each interval is preset. The collection frequency corresponding to the interval where the temperature change rate of the battery cell exceeding the safety temperature threshold is located is the collection frequency adjusted for the battery cell.

[0039] The battery cells that exceed the safety temperature threshold are virtually grouped according to the temperature change rate and divided into corresponding intervals, and the collection frequency of the corresponding interval is adjusted. The battery cells after the acquisition frequency adjustment are virtually grouped 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.

[0040] The adjustment of the acquisition frequency is real-time and dynamic. If the temperature change rate of a battery cell in the high-frequency group calculated based on the measured temperature data decreases within a certain time range and falls into another interval, the acquisition frequency will be adjusted while adjusting the battery cell to the corresponding acquisition frequency grouping, thereby realizing adaptive control of the acquisition frequency and grouping to achieve the purpose of balancing the relationship between the acquisition frequency and data processing.

[0041] Several intervals can be divided according to the following rules: In the low change range, the temperature change rate per unit time is less than 1 degree at the original acquisition frequency; 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 2 degrees.

[0042] The sampling 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.

[0043] If the battery cell temperature change rate exceeds the theoretical power battery cell temperature change rate, it will be monitored closely and classified into the high change range.

[0044] Abnormal battery temperature may be caused by the quality of the battery itself, or it may be caused by problems such as charging and discharging power, or welding process. This application further monitors the temperature in order to locate the cause of the temperature increase and provide a reference solution for subsequent processing methods.

[0045] If the temperature collected in the current round in the regulation module is greater than or equal to the safety temperature threshold, the warning will be activated and the battery cell number whose temperature exceeds the safety temperature threshold will be displayed. Because the safety temperature threshold is set lower than the dangerous temperature (working at this temperature, the risk of spontaneous combustion and other hazards is greater), 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 the battery cell with this number, and adjust the temperature collection frequency to the preset maximum collection frequency for collection, so that corresponding measures can be taken more quickly to avoid danger.

[0046] 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 the temperature.

[0047] Since the acquisition frequency may be different, when making comparisons, the temperature for comparison is selected through the following reference ideas: 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 this battery cell cannot be divided evenly by the acquisition frequency of the battery cell to be compared, the temperature of this 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.

[0048] If the temperature difference between this 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, it indicates that the temperature of other battery cells is also rising. It is judged that the temperature rise may be caused by the charging power or the charging equipment, and a prompt to adjust the charging power and check the charging equipment is given. Adjusting the charging power is to adjust in the direction of reducing the charging power. For the first adjustment, a wide range of values ​​can be adjusted. If a maximum power reduction value is preset, the charging power is reduced by a maximum power reduction value during the first adjustment.

[0049] If within the preset time period, the temperature difference between this battery cell and 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, and it is judged that there may be a problem with the battery cell itself, such as a battery cell problem or a battery welding process, and a prompt is given that there may be a problem with this battery cell.

[0050] Of course, the above judgments on the causes of the battery temperature increase are for reference only, not the final maintenance conclusions.

[0051] The present invention also provides a method for monitoring and adjusting the state of a power battery, comprising the following steps: 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; 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, the temperature change rate is calculated, and it is determined whether the temperature change rate of each battery cell exceeds the safe rate threshold. If neither exceeds the safety rate threshold, a battery cell state equation is established based on 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 current power battery temperature prediction value and the error covariance matrix to predict the next round of temperature. If the predicted temperature of the next round exceeds the safety temperature threshold, the collection frequency of the battery cell is adjusted.

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, the temperature change rate is calculated, and it is determined 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 will be adjusted.

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, and the temperature is collected using the adjusted acquisition frequency.

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, the temperature change rate is calculated, and it is determined 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 will be adjusted.

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