Energy storage control system and method for sodium ion capacitor

Abstract

The invention discloses an energy storage control system and method for a sodium ion capacitor, and relates to the technical field of energy storage control, and the method comprises the following steps: collecting energy storage control related data information of the sodium ion capacitor, and carrying out the data preprocessing of the collected information; the local hot spot temperature is predicted by collecting current, voltage and surface temperature data of the sodium ion capacitor, and when the local hot spot temperature exceeds a set safety threshold value during charging and discharging, the voltage is adjusted according to a preset rule; based on the health state and the historical temperature data, adaptively adjusting the parameter a, and calculating the charge quantity in the charging and discharging process by using a trapezoidal integral method; and updating the state of charge of the sodium ion capacitor by combining the correction effect of the parameter a on the target state of charge according to the charge quantity integral result during charging and discharging, thereby realizing the energy storage control of the sodium ion capacitor.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage control, and particularly to an energy storage control system and method for a sodium-ion capacitor. Background Art

[0002] With the continuous growth of energy storage demand and the continuous improvement of the safety requirements for energy storage devices, the sodium-ion capacitor energy storage technology has become increasingly important in the energy storage field. As the key to ensuring the stability of sodium-ion capacitors, its energy storage control effect is related to the overall performance and safety of the energy storage system.

[0003] However, traditional sodium-ion capacitor energy storage control methods often face the following problems when dealing with complex charge-discharge processes and state-of-charge management: First, the data acquisition and processing capabilities are insufficient. During the charge-discharge process of sodium-ion capacitors, rich electrical, thermal and other data will be generated, and traditional methods only rely on a few sensors to collect limited data. Second, the temperature prediction and control accuracy are low. Traditional methods are difficult to predict the local hot spot temperature inside the capacitor. When the temperature is abnormal, the adjustment strategy is simple and rough, and the charge-discharge parameters cannot be finely adjusted according to the real-time temperature change, which easily causes the capacitor to overheat and affects its performance and life. In addition, there is a lack of an adaptive parameter adjustment and state-of-charge management mechanism. Traditional energy storage control cannot optimize control parameters in real time according to the health state and temperature history data of the capacitor, and the state-of-charge calculation and adjustment methods are single, which cannot meet the energy storage requirements under different working conditions. In view of the above problems, although the existing sodium-ion capacitor energy storage control systems have achieved a certain degree of automation, they lack intelligent real-time monitoring when facing complex charge-discharge processes and cannot meet the growing energy storage and application requirements. Summary of the Invention

[0004] The purpose of the present invention is to provide an energy storage control system and method for a sodium-ion capacitor to solve the problems raised in the prior art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An energy storage control method for a sodium-ion capacitor, the method comprising the following steps: Collect the energy storage control-related data information of the sodium-ion capacitor, and perform data preprocessing on the collected information; Predict the local hot spot temperature by collecting the current, voltage and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to a preset rule; Based on the health state and temperature history data, adaptively adjust the parameter a, and calculate the charge quantity during the charge-discharge process by using the trapezoidal integration method; Update the state of charge of the sodium-ion capacitor according to the integration result of the charge quantity during charge and discharge and the correction effect of the parameter a on the target state of charge.

[0006] Collect the energy storage control-related data information of the sodium-ion capacitor, and perform data preprocessing on the collected information. The specific steps are as follows: Collect the voltage data of the sodium-ion capacitor through a voltage sensor; collect the current data of the sodium-ion capacitor through a current sensor; use an NTC array to monitor the temperature data of the sodium-ion capacitor; Calculate the initial state of charge of the sodium-ion capacitor. The calculation formula is as follows: SOC init =(V cell -V min ) / (V max -V min )*100%; Among them, SOC init represents the initial state of charge of the sodium-ion capacitor, V cell represents the real-time voltage of the sodium-ion capacitor, V min represents the minimum operating voltage of the sodium-ion capacitor, V max represents the maximum safe voltage of the sodium-ion capacitor; Obtain the data related to the energy storage control of the sodium-ion capacitor through sensors, clean and preprocess the obtained data related to the energy storage control of the sodium-ion capacitor, standardize the data format, and store all the data according to the unified database table structure; Use the Min-Max normalization algorithm to process the obtained data related to the energy storage control of the sodium-ion capacitor, and map the data uniformly to the [0,1] interval; Form data sets from the data after cleaning in each stage, denoted as {x1, x2,..., xn}, where x1, x2,..., xn represent the 1st, 2nd,..., nth data related to the energy storage control of the sodium-ion capacitor.

[0007] Predict the local hot spot temperature by collecting the current, voltage and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to the preset rules. The specific steps are as follows: Obtain the charge and discharge current, voltage and surface temperature data of the real-time sodium-ion capacitor, and predict the local hot spot temperature based on the thermoelectric coupling model; During the discharge stage, when the temperature of a local hot spot is monitored to exceed the safety threshold, a derating discharge strategy is triggered, and the discharge current is gradually reduced by b times the discharge current for every 1°C increase in temperature above the threshold. During the charging process after discharge, the remaining capacity is maintained at a times the initial state of charge. The temperature of the local hot spot is monitored during the charging process. When the temperature of the local hot spot is monitored to exceed the safety threshold, through closed-loop feedback control, the PID regulation control algorithm is used to dynamically adjust the charging cut-off voltage. Among them, the value of a is adaptively adjusted according to the state of health SOH and temperature history data, the safety threshold is set through historical data, and b represents the set discharge ratio.

[0008] Based on the state of health and temperature history data, the parameter a is adaptively adjusted, and the trapezoidal integration method is used to calculate the charge and discharge amount during the charge and discharge process. The specific steps are as follows: The parameter a is adaptively adjusted based on the state of health SOH and temperature history data, and is defined as follows: a = a0 - k * (1 - SOH) - m * (T1 - T ref ); where, a0 represents the initial capacity retention coefficient, k represents the SOH decay compensation coefficient, SOH represents the state of health quantified by the ratio of the current actual capacity to the factory nominal value, T ref represents the reference temperature when calibrating a0, and m represents the temperature compensation coefficient; Integrate according to the charge and discharge current of the sodium-ion capacitor during the charge and discharge process. Set the integration time interval to 1 second, and use the trapezoidal integration method to calculate the integral of the current over time from the start of charging to the current moment to obtain the charge amount charged into the sodium-ion capacitor, denoted as Q1; during the discharge process, integrate the absolute value of the discharge current to obtain the discharged charge amount, denoted as Q2.

[0009] Based on the charge and discharge amount integration results and the correction effect of the parameter a on the target state of charge, update the state of charge of the sodium-ion capacitor. The specific steps are as follows: The formula for the state of charge during discharge is as follows: soc2 = soc prec -Q2 / (η discharge *C) * 100%; where, soc2 represents the state of charge of the sodium-ion capacitor during discharge, soc prec represents the state of charge of the sodium-ion capacitor, C represents the actual charge amount of the sodium-ion capacitor, and η discharge represents the discharge coulomb efficiency; Update the state of charge of the sodium-ion capacitor according to the integration result of the charge amount. The formula for the state of charge of the sodium-ion capacitor during charging is as follows: soc1 = soc2 + η charge *Q1 / C * 100%; where, soc1 represents the state of charge of the sodium-ion capacitor during charging, and η charge represents the charge coulomb efficiency; Adjust according to the state of charge of the sodium-ion capacitor after current charge and discharge, so that the remaining capacity of the sodium-ion capacitor is maintained at a times that of the initial state of charge.

[0010] An energy storage control system for a sodium-ion capacitor, which is applied to an energy storage control method for a sodium-ion capacitor described in any one of claims 1-5. The system includes: a data acquisition module, a temperature monitoring and control module, a parameter adjustment module, and a state of charge management module. The data acquisition module is used to collect data information related to the energy storage control of the sodium-ion capacitor and perform data preprocessing on the collected information; the temperature monitoring and control module is used to predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, the voltage is adjusted according to a preset rule; the parameter adjustment module is used to adaptively adjust the parameter a based on the health state and temperature history data, and calculate the charge amount during the charge and discharge process using the trapezoidal integration method; the state of charge management module is used to update the state of charge of the sodium-ion capacitor based on the charge amount integration result during charge and discharge and the correction effect of the parameter a on the target state of charge. The output end of the data acquisition module is connected to the input end of the temperature monitoring and control module, the output end of the temperature monitoring and control module is connected to the input end of the parameter adjustment module, and the output end of the parameter adjustment module is connected to the input end of the state of charge management module.

[0011] The data acquisition module includes a data collection unit, an initial state of charge calculation unit, a preprocessing unit, and a data set construction unit; the data collection unit is used to collect the voltage data of the sodium-ion capacitor through a voltage sensor; collect the current data of the sodium-ion capacitor through a current sensor; monitor the temperature data of the sodium-ion capacitor using an NTC array; the initial state of charge calculation unit is used to calculate the initial state of charge of the sodium-ion capacitor; the preprocessing unit is used to clean, standardize the format, and store the acquired data, and process the data using the Min-Max normalization algorithm; the data set construction unit is used to form a data set from the cleaned data.

[0012] The temperature monitoring and control module includes a local hot spot temperature prediction unit, a discharge control unit, and a charge control unit; the local hot spot temperature prediction unit is used to predict the local hot spot temperature based on the thermoelectric coupling model, using real-time charge and discharge current, voltage, and surface temperature data; the discharge control unit is used to trigger a derating discharge strategy during the discharge stage when it is detected that the local hot spot temperature exceeds the safety threshold, and gradually reduce the discharge current by reducing the discharge current by b times for every 1°C increase in temperature, where b represents the set discharge ratio, and the safety threshold is set through historical data; the charge control unit is used to maintain the remaining capacity at a times that in the initial state of charge during the charging process after the discharge ends, monitor the local hot spot temperature during the charging process, and when it is detected that the local hot spot temperature exceeds the safety threshold, dynamically adjust the charging cut-off voltage through closed-loop feedback control using the PID regulation control algorithm, where the value of a is adaptively adjusted according to the state of health SOH and temperature historical data.

[0013] The parameter adjustment module includes a parameter adjustment unit and a charge quantity calculation unit; the parameter adjustment unit is used to adaptively adjust parameters based on the state of health SOH and temperature historical data; the charge quantity calculation unit is used to calculate the charge quantity during the charge and discharge process using the trapezoidal integration method with an integration time interval of 1 second.

[0014] The state of charge management module includes a discharge state of charge calculation unit, a charge state of charge calculation unit, and a capacity adjustment unit; the discharge state of charge calculation unit is used to calculate the discharge state of charge; the charge state of charge calculation unit is used to calculate the charge state of charge; the capacity adjustment unit is used to maintain the remaining capacity of the sodium-ion capacitor at a times that in the initial state of charge according to the current state of charge after charge and discharge.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention constructs a dynamic adjustment model based on the feedback of the capacitor state of health and state of charge, combines real-time monitoring data with the energy storage control process mechanism, and adaptively adjusts operating parameters such as the charging cut-off voltage and discharge current. Different from the fixed parameter or manual experience-based adjustment methods in the prior art, the present invention optimizes control parameters according to the real-time operating state of the capacitor and dynamically adjusts the energy storage control strategy; 2. By fusing multi-sensor data to collect real-time multi-parameter data such as current, voltage, and temperature of the sodium-ion capacitor during charge and discharge, combining the thermoelectric coupling model and the parameter adaptive adjustment algorithm, dynamically quantifying the correlation between each control link, and realizing the comprehensive evaluation of the whole process from data collection, temperature prediction, parameter adjustment to state of charge management. Description of the Drawings

[0016] Figure 1Schematic flow diagram of an energy storage control method for a sodium-ion capacitor according to the present invention; Figure 2 Schematic structural diagram of an energy storage control system for a sodium-ion capacitor according to the present invention. Detailed implementation manners

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] In the embodiment: As Figure 1 - Figure 2 shown, the present invention provides a technical solution, an energy storage control method for a sodium-ion capacitor, and the method includes the following steps: Collect data information related to the energy storage control of the sodium-ion capacitor, and perform data preprocessing on the collected information; Predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to the preset rules; Based on the health state and temperature history data, adaptively adjust the parameter a, and use the trapezoidal integration method to calculate the charge quantity during the charge and discharge process; According to the integration result of the charge quantity during charge and discharge, combined with the correction effect of the parameter a on the target state of charge, update the state of charge of the sodium-ion capacitor.

[0019] Collect data information related to the energy storage control of the sodium-ion capacitor, and perform data preprocessing on the collected information. The specific steps include: Collect the voltage data of the sodium-ion capacitor through a voltage sensor; collect the current data of the sodium-ion capacitor through a current sensor; use an NTC array to monitor the temperature data of the sodium-ion capacitor; Calculate the initial state of charge of the sodium-ion capacitor, and the calculation formula is as follows: SOC init =(V cell -V min ) / (V max -V min )*100%; where, SOC init represents the initial state of charge of the sodium-ion capacitor, V cell represents the real-time voltage of the sodium-ion capacitor, V min represents the minimum working voltage of the sodium-ion capacitor, V max represents the maximum safety voltage of the sodium-ion capacitor; Obtain data related to the energy storage control of sodium-ion capacitors through sensors, clean and preprocess the obtained data related to the energy storage control of sodium-ion capacitors, standardize the data format, and store all data according to a unified database table structure; Use the Min-Max normalization algorithm to process the obtained data related to the energy storage control of sodium-ion capacitors, and map the data uniformly to the interval [0, 1]; Form data sets from the data after cleaning in each stage, denoted as {x1, x2,..., xn}, where x1, x2,..., xn represent the 1st, 2nd,..., nth data related to the energy storage control of sodium-ion capacitors.

[0020] Specifically, select a sodium-ion capacitor with a rated capacity C = 100 Ah, whose minimum operating voltage V min = 2.0 V, and the maximum safe voltage V max = 4.0 V, equipped with a voltage sensor, a current sensor, and an NTC array. The voltage sensor collects the capacitor voltage data, the current sensor collects the current data, and the NTC array monitors the temperature data. The acquisition frequency is set to 10 times per second. At an ambient temperature of 25°C, the real-time voltage of the sodium-ion capacitor is 3.5 V. Determine the initial state of charge of the sodium-ion capacitor to be 75% and the discharge current to be -10 A according to the formula; Clean the collected data, remove outliers (instantaneous current spikes), standardize the data format, store it in a unified database table structure, use the Min-Max normalization algorithm to process the obtained data related to the energy storage control of sodium-ion capacitors, map the data uniformly to the interval [0, 1], and form a data set from the cleaned data.

[0021] Predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to the preset rules. The specific steps are as follows: Predict the local hot spot temperature based on the thermoelectric coupling model by obtaining the charge and discharge current, voltage, and surface temperature data of the real-time sodium-ion capacitor; During the discharge stage, when it is detected that the local hot spot temperature exceeds the safety threshold, a derating discharge strategy is triggered, and the discharge current is gradually reduced by b times the discharge current for every 1°C increase in temperature; during the charging process after discharge, the remaining capacity is maintained at a times that in the initial state of charge, and the local hot spot temperature during the charging process is monitored. When it is detected that the local hot spot temperature exceeds the safety threshold, through closed-loop feedback control, the PID regulation control algorithm is used to dynamically adjust the charging cut-off voltage. Among them, the value of a is adaptively adjusted according to the state of health (SOH) and temperature history data, the safety threshold is set through historical data, and b represents the set discharge ratio.

[0022] Specifically, given a thermal resistance of 0.1°C / W, a real-time internal resistance of 0.05 Ω, and a surface temperature of 30°C, the local hot spot temperature inside the sodium-ion capacitor is calculated to be 30.5°C according to the thermal-electrical coupling model. During the discharge process, the discharge ratio b = 0.1 is set, and the local hot spot temperature safety threshold is determined to be 40°C through historical data. When it is detected that the local hot spot temperature exceeds the safety threshold of 40°C, a derating discharge strategy is triggered, and the discharge current is gradually reduced by 0.1 times the discharge current for every 1°C increase in temperature.

[0023] Based on the state of health and temperature history data, the parameter a is adaptively adjusted, and the trapezoidal integration method is used to calculate the charge and discharge process of the charge quantity. The specific steps are as follows: The parameter a is adaptively adjusted based on the state of health SOH and temperature history data, and is defined as follows: a = a0 - k * (1 - SOH) - m * (T1 - T ref ); where, a0 represents the initial capacity retention coefficient, k represents the SOH decay compensation coefficient, SOH represents the state of health quantified by the ratio of the current actual capacity to the factory nominal value, T ref represents the reference temperature when calibrating a0, and m represents the temperature compensation coefficient. Integrate according to the charge and discharge current of the sodium-ion capacitor during the charge and discharge process. Set the integration time interval to 1 second, and use the trapezoidal integration method to calculate the integral of the current with respect to time from the start of charging to the current moment to obtain the charge quantity charged into the sodium-ion capacitor, denoted as Q1; during the discharge process, integrate the absolute value of the discharge current to obtain the discharged charge quantity, denoted as Q2.

[0024] Specifically, the health state of the capacitor is 90%. The initial capacity retention coefficient a0 is set to 0.9, the SOH decay compensation coefficient k is 0.3, the temperature compensation coefficient m is 0.02, and the reference temperature for calibrating a0 is 25°C. Substituting the data into the formula gives a = 0.79. Using the trapezoidal integration method, with an integration time interval of 1 second to calculate the charge quantity, during a period of discharge, the discharged charge quantity Q2 is obtained through integral calculation; during the subsequent charging process, from the start of charging to a certain moment, the charged charge quantity Q1 is calculated.

[0025] Based on the integral results of the charge quantity during charge and discharge, combined with the corrective effect of parameter a on the target state of charge, the state of charge of the sodium-ion capacitor is updated. The specific steps include: The formula for the state of charge during discharge is as follows: soc2 = soc prec -Q2 / (η discharge *C)*100%; where soc2 represents the state of charge of the sodium-ion capacitor during discharge, soc prec represents the state of charge of the sodium-ion capacitor, C represents the actual charge quantity of the sodium-ion capacitor, and η discharge represents the discharge coulomb efficiency; According to the integral results of the charge quantity, the state of charge of the sodium-ion capacitor is updated. The formula for the state of charge of the sodium-ion capacitor during charging is as follows: soc1 = soc2 + η charge *Q1 / C*100%; where soc1 represents the state of charge of the sodium-ion capacitor during charging, and η charge represents the charge coulomb efficiency; Adjust according to the state of charge of the sodium-ion capacitor after the current charge and discharge, so that the remaining capacity of the sodium-ion capacitor is maintained at a times the initial state of charge.

[0026] Specifically, given that the state of charge before discharge is 75%, the discharge coulomb efficiency is 0.98, and the charge coulomb efficiency is 0.97, according to the formula, the state of charge during discharge is 64.8%; after discharge, charging is carried out. The state of charge before charging is 64.8%. According to the formula, the state of charge of the sodium-ion capacitor during charging is 79.4%. Adjust according to the state of charge of the sodium-ion capacitor after the current charge and discharge, so that the remaining capacity of the sodium-ion capacitor is maintained at 0.79 times the initial state of charge.

[0027] An energy storage control system for a sodium-ion capacitor, which is applied to an energy storage control method for a sodium-ion capacitor described in any one of claims 1-5. The system includes: a data acquisition module, a temperature monitoring and control module, a parameter adjustment module, and a state of charge management module. The data acquisition module is used to collect data information related to the energy storage control of the sodium-ion capacitor and perform data preprocessing on the collected information. The temperature monitoring and control module is used to predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, the voltage is adjusted according to a preset rule. The parameter adjustment module is used to adaptively adjust the parameter a based on the health state and temperature history data, and calculate the charge and discharge process charge by using the trapezoidal integration method. The state of charge management module is used to update the state of charge of the sodium-ion capacitor according to the charge integration result during charge and discharge, combined with the correction effect of the parameter a on the target state of charge. The output end of the data acquisition module is connected to the input end of the temperature monitoring and control module, the output end of the temperature monitoring and control module is connected to the input end of the parameter adjustment module, and the output end of the parameter adjustment module is connected to the input end of the state of charge management module.

[0028] The data acquisition module includes a data collection unit, an initial state of charge calculation unit, a preprocessing unit, and a data set construction unit. The data collection unit is used to collect the voltage data of the sodium-ion capacitor through a voltage sensor, collect the current data of the sodium-ion capacitor through a current sensor, and monitor the temperature data of the sodium-ion capacitor using an NTC array. The initial state of charge calculation unit is used to calculate the initial state of charge of the sodium-ion capacitor. The preprocessing unit is used to clean, standardize the format, and store the acquired data, and process the data using the Min-Max normalization algorithm. The data set construction unit is used to form a data set from the cleaned data.

[0029] The temperature monitoring and control module includes a local hot spot temperature prediction unit, a discharge control unit, and a charge control unit. The local hot spot temperature prediction unit is used to predict the local hot spot temperature based on the thermal-electrical coupling model, using the real-time charge and discharge current, voltage, and surface temperature data. The discharge control unit is used to trigger a derating discharge strategy when it is detected that the local hot spot temperature exceeds the safety threshold during the discharge stage, and gradually reduce the discharge current by b times the discharge current for every 1°C increase in temperature, where b represents the set discharge ratio, and the safety threshold is set through historical data. The charge control unit is used to maintain the remaining capacity as a times the initial state of charge during the charging process after the discharge ends, monitor the local hot spot temperature during the charging process, and when it is detected that the local hot spot temperature exceeds the safety threshold, dynamically adjust the charging cut-off voltage through closed-loop feedback control using the PID regulation control algorithm, where the value of a is adaptively adjusted according to the health state SOH and temperature history data.

[0030] The parameter adjustment module includes a parameter adjustment unit and a charge quantity calculation unit; the parameter adjustment unit is used to adaptively adjust parameters based on the state of health (SOH) and temperature history data; the charge quantity calculation unit is used to calculate the charge quantity during the charge and discharge process by using the trapezoidal integration method with an integration time interval of 1 second.

[0031] The state of charge management module includes a discharge state of charge calculation unit, a charge state of charge calculation unit, and a capacity adjustment unit; the discharge state of charge calculation unit is used to calculate the discharge state of charge; the charge state of charge calculation unit is used to calculate the charge state of charge; the capacity adjustment unit is used to maintain the remaining capacity of the sodium-ion capacitor as a times that in the initial state of charge according to the state of charge after the current charge and discharge.

[0032] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A energy storage control method for a sodium-ion capacitor, characterized in that: The method includes the following steps: Collect data information related to the energy storage control of the sodium-ion capacitor, and perform data preprocessing on the collected information; Predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to a preset rule; Based on the state of health and temperature history data, adaptively adjust the parameter a, and calculate the charge quantity during the charge and discharge process using the trapezoidal integration method; According to the integral result of the charge quantity during charge and discharge, combined with the correction effect of the parameter a on the target state of charge, update the state of charge of the sodium-ion capacitor.

2. The energy storage control method for a sodium-ion capacitor according to claim 1, characterized in that: Collect data information related to the energy storage control of the sodium-ion capacitor, and perform data preprocessing on the collected information. The specific steps include: Collect the voltage data of the sodium-ion capacitor through a voltage sensor; collect the current data of the sodium-ion capacitor through a current sensor; use an NTC array to monitor the temperature data of the sodium-ion capacitor; Calculate the initial state of charge of the sodium-ion capacitor. The calculation formula is as follows: SOC init =(V cell -V min ) / (V max -V min )*100%; Among them, SOC init represents the initial charge state of the sodium-ion capacitor, V cell represents the real-time voltage of the sodium-ion capacitor, V min represents the minimum operating voltage of the sodium-ion capacitor, V max represents the maximum safe voltage of the sodium-ion capacitor; Obtain data related to the energy storage control of the sodium-ion capacitor through sensors, clean and preprocess the obtained data related to the energy storage control of the sodium-ion capacitor, standardize the data format, and store all data according to a unified database table structure; Use the Min-Max normalization algorithm to process the obtained data related to the energy storage control of the sodium-ion capacitor, and map the data uniformly to the interval [0,1]; Form datasets from the data cleaned in each stage, denoted as {x1, x2,..., xn}, where x1, x2,..., xn represent the 1st, 2nd,..., nth data related to the energy storage control of the sodium-ion capacitor.

3. The energy storage control method for a sodium-ion capacitor according to claim 2, characterized in that: Predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to a preset rule. The specific steps include: Obtain the charge and discharge current, voltage, and surface temperature data of the real-time sodium-ion capacitor, and predict the local hot spot temperature based on the thermal-electrical coupling model; During the discharge stage, when it is monitored that the local hot spot temperature exceeds the safety threshold, trigger a derating discharge strategy, and gradually reduce the discharge current by b times the discharge current for every 1°C increase in temperature; during the charging process after the discharge ends, maintain the remaining capacity as a times the initial state of charge, monitor the local hot spot temperature during the charging process, and when it is monitored that the local hot spot temperature exceeds the safety threshold, through closed-loop feedback control, use the PID regulation control algorithm to dynamically adjust the charging cut-off voltage, where the value of a is adaptively adjusted according to the state of health SOH and temperature history data, the safety threshold is set through historical data, and b represents the set discharge ratio.

4. A energy storage control method for a sodium ion capacitor according to claim 3, characterized in that: Based on the state of health and temperature history data, adaptively adjust the parameter a, and calculate the charge quantity during the charge and discharge process using the trapezoidal integration method. The specific steps include: Based on the health state of health (SOH) and temperature historical data, parameter a is adaptively adjusted and defined as follows: a = a0 - k * (1 - SOH) - m * (T1 - T ref ); where, a0 represents the initial capacity retention coefficient, k represents the SOH attenuation compensation coefficient, SOH represents the health state quantified by the ratio of the current actual capacity to the factory nominal value, T ref represents the reference temperature when calibrating a0, and m represents the temperature compensation coefficient; Integrate the charge and discharge current of the sodium-ion capacitor during the charge and discharge process. Set the integration time interval to 1 second, and use the trapezoidal integration method to calculate the integral of the current with respect to time from the start of charging to the current moment to obtain the charge amount charged into the sodium-ion capacitor, denoted as Q1; during the discharge process, integrate the absolute value of the discharge current to obtain the discharged charge amount, denoted as Q2.

5. A method for energy storage control of a sodium-ion capacitor according to claim 4, characterized in that: Based on the charge integration results during charge and discharge, combined with the correction effect of parameter a on the target state of charge, update the state of charge of the sodium-ion capacitor. The specific steps include: The calculation formula for the state of charge during discharge is as follows: soc2 = soc prec -Q2 / (η discharge *C)*100%; where, soc2 represents the state of charge of the sodium-ion capacitor during discharge, soc prec represents the state of charge of the sodium-ion capacitor, C represents the actual charge quantity of the sodium-ion capacitor, η discharge represents the discharge coulomb efficiency; Update the state of charge of the sodium-ion capacitor according to the integration result of the charge quantity. The calculation formula for the state of charge of the sodium-ion capacitor during charging is as follows: soc1 = soc2 + η charge *Q1 / C*100%; where, soc1 represents the state of charge of the sodium-ion capacitor during charging, and η charge represents the charging coulomb efficiency; Adjust according to the state of charge of the sodium-ion capacitor after the current charge and discharge, so that the remaining capacity of the sodium-ion capacitor is maintained at a times that of the initial state of charge.

6. An energy storage control system for a sodium-ion capacitor, applied to an energy storage control method for a sodium-ion capacitor according to any one of claims 1-5, characterized in that: The system includes: a data acquisition module, a temperature monitoring and control module, a parameter adjustment module, and a state of charge management module. The data acquisition module is used to collect data information related to the energy storage control of the sodium-ion capacitor and perform data preprocessing on the collected information; the temperature monitoring and control module is used to predict the local hot spot temperature by collecting the current, voltage, and surface temperature data of the sodium-ion capacitor. When the local hot spot temperature exceeds the set safety threshold during charge and discharge, adjust the voltage according to the preset rules; the parameter adjustment module is used to adaptively adjust parameter a based on the health status and temperature history data, and calculate the charge amount during the charge and discharge process using the trapezoidal integration method; the state of charge management module is used to update the state of charge of the sodium-ion capacitor based on the charge integration results during charge and discharge, combined with the correction effect of parameter a on the target state of charge. The output end of the data acquisition module is connected to the input end of the temperature monitoring and control module, the output end of the temperature monitoring and control module is connected to the input end of the parameter adjustment module, and the output end of the parameter adjustment module is connected to the input end of the state of charge management module.

7. An energy storage control system for a sodium-ion capacitor according to claim 6, characterized in that: The data acquisition module includes a data collection unit, an initial state of charge calculation unit, a preprocessing unit, and a data set construction unit; the data collection unit is used to collect the voltage data of the sodium-ion capacitor through a voltage sensor; Collect the current data of the sodium-ion capacitor through a current sensor; Use an NTC array to monitor the temperature data of the sodium-ion capacitor; The initial state of charge calculation unit is used to calculate the initial state of charge of the sodium-ion capacitor; the preprocessing unit is used to clean, standardize the format, and store the acquired data, and process the data using the Min-Max normalization algorithm; The data set construction unit is used to form a data set from the cleaned data.

8. The energy storage control system for a sodium ion capacitor according to claim 7, characterized in that: The temperature monitoring and control module includes a local hot spot temperature prediction unit, a discharge control unit, and a charge control unit; the local hot spot temperature prediction unit is used to predict the local hot spot temperature based on the thermo-electric coupling model by using real-time charge and discharge current, voltage, and surface temperature data; the discharge control unit is used to trigger a derating discharge strategy during the discharge stage when it monitors that the local hot spot temperature exceeds the safety threshold, and gradually reduce the discharge current by b times the discharge current for every 1°C increase in temperature, where b represents the set discharge ratio, and the safety threshold is set through historical data; the charge control unit is used to maintain the remaining capacity at a times that in the initial state of charge during the charging process after the discharge ends, monitor the local hot spot temperature during the charging process, and when it monitors that the local hot spot temperature exceeds the safety threshold, dynamically adjust the charging cut-off voltage through closed-loop feedback control by using the PID regulation control algorithm, where the value of a is adaptively adjusted according to the state of health SOH and temperature historical data.

9. The energy storage control system for a sodium-ion capacitor according to claim 8, wherein: The parameter adjustment module includes a parameter adjustment unit and a charge quantity calculation unit; the parameter adjustment unit is used to adaptively adjust parameters based on the state of health SOH and temperature historical data; the charge quantity calculation unit is used to calculate the charge quantity during the charge and discharge process by using the trapezoidal integration method with an integration time interval of 1 second.

10. A energy storage control system for a sodium-ion capacitor according to claim 9, characterized in that: The state of charge management module includes a discharge state of charge calculation unit, a charge state of charge calculation unit, and a capacity adjustment unit; the discharge state of charge calculation unit is used to calculate the discharge state of charge; the charge state of charge calculation unit is used to calculate the charge state of charge; the capacity adjustment unit is used to maintain the remaining capacity of the sodium-ion capacitor at a times that in the initial state of charge according to the current state of charge after charge and discharge.

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