Temperature response-based dynamic regulation method and system for capacitance voltage and terminal

Abstract

The application provides a temperature response-based dynamic regulation method and system for a capacitor voltage and a terminal, specifically, a working voltage, a current and a shell temperature of a super capacitor are acquired in real time; two characteristic frequency point impedances are extracted through transient analysis of charging and discharging, high and low frequency equivalent series resistances are calculated, and a health state estimation value is updated by a weighted difference value of the two; a basic aging rate is calculated based on the estimation value, a real-time voltage and the temperature through an electrochemical aging model; a second-order time derivative of the shell temperature is used as a thermal shock factor to correct the basic aging rate, and a predicted aging rate is obtained; a voltage adjustment factor for delaying electrolyte decomposition is generated according to the predicted aging rate and the health state; a reference cutoff voltage is obtained by querying a mapping table in combination with a current power or energy priority working mode; the reference cutoff voltage is adjusted by the voltage adjustment factor to obtain a target cutoff voltage, and a closed-loop control is performed on a charging and discharging process according to the target cutoff voltage.

Description

Technical Field

[0001] This application belongs to the field of regulation, and in particular relates to a method, system and terminal for dynamic regulation of capacitor voltage based on temperature response. Background Technology

[0002] During long-term operation, the performance of supercapacitors gradually degrades, manifested as an increase in equivalent series resistance (ESR) and a decrease in capacitance, a process known as aging. Factors contributing to aging include operating voltage and temperature. Prolonged operation under excessively high voltage or high temperature environments accelerates the decomposition of the internal electrolyte and the degradation of the electrode materials, thus shortening the capacitor's lifespan. While the charging cut-off voltage slows down aging, it cannot be adjusted according to the capacitor's actual health status and real-time operating conditions, limiting energy and power performance when the capacitor is in good health.

[0003] Online monitoring of the state of health (SOH) of supercapacitors can be used to assess SOH by measuring DC internal resistance or AC impedance at a single frequency. However, supercapacitor aging is an electrochemical process, and changes in the impedance spectrum at different frequency bands reflect different aging mechanisms. For example, high-frequency resistance is mainly related to the ohmic polarization of the electrolyte and current collector, while low-frequency resistance is related to charge transfer and ion diffusion processes at the electrode / electrolyte interface. Therefore, it is difficult to measure the true health status based solely on a single resistance parameter. Furthermore, existing aging prediction models focus on the static effects of voltage and temperature, assuming that the aging rate is fixed at a constant voltage and temperature. In practical applications, load fluctuations often lead to rapid temperature changes, resulting in thermal shock. Rapid temperature rises and falls can induce thermomechanical stress between internal materials, accelerating the destruction of the microstructure. Therefore, existing technologies still have room for improvement in how to combine multi-dimensional impedance information to assess SOH and incorporate thermal shock factors to achieve optimized control of the operating voltage. Summary of the Invention

[0004] This invention proposes a temperature-response-based dynamic capacitor voltage control method to address the shortcomings of existing technologies in evaluating state of impedance (SOH) using multi-dimensional impedance information and incorporating thermal shock factors to achieve optimized control of the operating voltage. The method includes: The real-time operating voltage, operating current, and shell temperature of the supercapacitor are obtained; by analyzing the voltage and current response during the charging and discharging switching transient process, impedance information at least two characteristic frequency points is extracted, the high-frequency equivalent series resistance and the low-frequency equivalent series resistance are calculated, and the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance is used to update the estimated health status of the supercapacitor. The basic aging rate is calculated based on the estimated health status, real-time operating voltage, and housing temperature. At the same time, the second time derivative of the housing temperature within a preset time window is calculated as a thermal shock factor, and the basic aging rate is corrected using the thermal shock factor to obtain the predicted aging rate for the next time step. Based on the predicted aging rate and health status estimate, a voltage adjustment factor is generated to delay electrolyte decomposition; combined with the current power-priority or energy-priority operating mode of the supercapacitor, the reference cutoff voltage is obtained by querying the preset voltage reference-operating mode mapping table. The reference cutoff voltage is adjusted using the voltage adjustment factor to obtain the target cutoff voltage, and the charging and discharging process of the supercapacitor is controlled in a closed loop based on the target cutoff voltage.

[0005] Furthermore, the present invention also relates to a temperature-responsive capacitor voltage dynamic control system, comprising the following modules: The update module is used to obtain the real-time operating voltage, operating current and shell temperature of the supercapacitor; by analyzing the voltage and current response during the charging and discharging switching transient process, the impedance information of at least two characteristic frequency points is extracted, the high-frequency equivalent series resistance and the low-frequency equivalent series resistance are calculated, and the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance is used to update the health status estimate of the supercapacitor. The correction module is used to calculate the basic aging rate based on the health status estimate, real-time operating voltage and shell temperature; at the same time, it calculates the second time derivative of the shell temperature within a preset time window as a thermal shock factor, and uses the thermal shock factor to correct the basic aging rate to obtain the predicted aging rate for the next time step. The query module is used to generate a voltage adjustment factor for delaying electrolyte decomposition based on the predicted aging rate and health status estimate; and to obtain the reference cutoff voltage from the preset voltage reference-operating mode mapping table in combination with the current power-priority or energy-priority operating mode of the supercapacitor. The control module is used to adjust the reference cutoff voltage using the voltage adjustment factor to obtain the target cutoff voltage, and to perform closed-loop control of the charging and discharging process of the supercapacitor based on the target cutoff voltage.

[0006] In addition, the present invention also relates to a temperature-responsive capacitor voltage dynamic control terminal, the control terminal comprising at least a memory and a processor, wherein the memory stores a temperature-responsive capacitor voltage dynamic control program, and when the program is executed by the processor, it implements the steps of the control method as described above.

[0007] This invention extracts multi-frequency impedance information by analyzing the electrical response during the transient process of charge-discharge switching, enabling the assessment of the health status of supercapacitors. By utilizing the second-order time derivative of the shell temperature to represent the thermal shock effect and using this to correct the baseline aging rate, a more comprehensive aging rate prediction result is obtained. Based on this, a voltage adjustment factor is generated, and combined with the power or energy-priority operating mode requirements, the charge-discharge cutoff voltage is adjusted and controlled in a closed loop. While ensuring the supercapacitor's performance output, this suppresses key aging mechanisms, especially electrolyte decomposition, thereby delaying the performance degradation process of the supercapacitor. This achieves the goal of extending the overall service life, improving the long-term operational stability and economic benefits of the energy storage system. Attached Figure Description

[0008] Figure 1 A flowchart of the first embodiment; Figure 2 This is a schematic diagram of a signal acquisition system; Figure 3 This is a schematic diagram for calculating the predicted aging rate. Detailed Implementation

[0009] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0010] In the first embodiment, the present invention proposes a method for dynamic regulation of capacitor voltage based on temperature response, such as... Figure 1 ,include: S1, Obtain the real-time operating voltage, operating current and shell temperature of the supercapacitor; By analyzing the voltage and current response during the charging and discharging switching transient process, extract the impedance information at at least two characteristic frequency points, calculate the high-frequency equivalent series resistance and the low-frequency equivalent series resistance, and use the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance to update the estimated health status of the supercapacitor. Voltage is measured using a voltage divider resistor and differential amplifier circuit connected in parallel across the supercapacitor; current is measured using a Hall effect current sensor connected in series in the main circuit; and temperature is measured using an NTC thermistor tightly bonded to the surface of the supercapacitor casing. All analog signals are acquired by a 16-bit analog-to-digital converter (ADC), and the digitized results are read by an STM32 series microcontroller every 10ms. Figure 2 .

[0011] The microcontroller monitors the current direction in real time. When it detects a zero-crossing point where the current changes from positive (charging) to negative (discharging), it immediately acquires voltage and current data at a high frequency of 1kHz for 200ms before and after the switching point. The high-frequency equivalent series resistance Rhigh-frequency = ΔV1 / ΔI is calculated using the ratio of the voltage jump value ΔV1 to the current step value ΔI 1ms after the current switching. This resistance reflects the ohmic internal resistance. The low-frequency equivalent series resistance Rlow-frequency = ΔV2 / ΔI is calculated using the ratio of the total voltage change value ΔV2 to the current step value ΔI 150ms after the current switching. This resistance includes the impedance of charge transfer and diffusion processes. Optionally, voltage and current data of the supercapacitor during the charging and discharging transient process are collected. Fourier transform is performed on these transient data to convert them from the time domain to the frequency domain, thereby obtaining the impedance response at different frequencies. The real part of the impedance at a preset high-frequency point is extracted as the high-frequency equivalent series resistance, and the real part of the impedance at a preset low-frequency point is extracted as the low-frequency equivalent series resistance. The preset high-frequency point is typically around 1kHz to 10kHz, and the preset low-frequency point is preferably between 0.01Hz and 1Hz. In one embodiment, the health status (SOH) value is updated according to the formula SOH = (1 - (current weighted difference - new component weighted difference)) / (life end weighted difference - new component weighted difference), where the weighted difference = 0.8 × Rlow frequency - 0.2 × Rhigh frequency.

[0012] In yet another optional embodiment, updating the health status estimate of the supercapacitor using the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance includes: Perform Fourier transform on the voltage and current data during charge-discharge switching transients to calculate the preset high-frequency point. The real part of the impedance is used as the high-frequency equivalent series resistance. and preset low frequency points The real part of the impedance is used as the low-frequency equivalent series resistance. ; Update the health status estimate using the following formula. : in, The value is the estimated health status at the previous moment, and w is the preset weighting coefficient. This is the reference value for the resistance used for normalization.

[0013] During the transient process of a supercapacitor switching from charging to discharging or from discharging to charging, high-frequency sampling of voltage and current data is collected. For example, when the operating current switches from 50A discharging to 50A charging, data is continuously collected for 200ms at a sampling rate of 10kHz to obtain the voltage sequence V(t) and current sequence I(t) including the switching point. A Fast Fourier Transform (FFT) algorithm is applied to the collected voltage and current time series data to transform the data from the time domain to the frequency domain, obtaining the voltage spectrum V(f) and the current spectrum I(f). The complex impedance of the supercapacitor at different frequencies is obtained by calculating Z(f) = V(f) / I(f), and the real part, i.e., the equivalent series resistance, is extracted. .

[0014] Set preset high frequency point At 1000Hz, the real part of the impedance mainly reflects the ohmic internal resistance of the electrolyte and electrode materials, for example, calculated as follows: mΩ. Then set a preset low-frequency point. The impedance is 1 Hz. Here, the real part of the impedance, in addition to the ohmic internal resistance, also includes an impedance component related to charge transfer and ion diffusion. This component is sensitive to aging, for example, as calculated... mΩ. The health state is updated using these two resistance values. Assume the health state at the previous moment. The accuracy is 98.5%, the preset weighting coefficient w is 0.05, and the normalized resistance reference value is... It is 15mΩ. Substituting into the formula for calculation, we get... By monitoring the difference between low-frequency and high-frequency resistance, performance degradation caused by changes in electrode pore structure and electrolyte decomposition aging mechanisms can be detected.

[0015] In an alternative embodiment, to prevent the health status estimate from declining too rapidly, a formula is used. Update health status estimates.

[0016] S2, the basic aging rate is calculated based on the estimated health status, real-time operating voltage and shell temperature; at the same time, the second time derivative of the shell temperature within a preset time window is calculated as a thermal shock factor, and the basic aging rate is corrected using the thermal shock factor to obtain the predicted aging rate for the next time step. The baseline aging rate Rbase is calculated using the Arrhenius empirical formula. Simultaneously, the temperature values ​​for each second within the past minute are cached, and the second derivative Tsecond of the current temperature with respect to time is calculated using the five-point central difference method. The absolute value is then used as the thermal shock factor Fthermal shock. In one embodiment, the predicted aging rate is: Rbase × (1 + thermal shock sensitivity coefficient k × Fthermal shock).

[0017] In an optional embodiment, the calculation of the base aging rate based on the health status estimate, real-time operating voltage, and housing temperature includes: The basic aging rate The calculation formula is: Where A is the pre-exponential factor, Let R be the activation energy, R be the ideal gas constant, and T be the absolute temperature scale of the shell temperature. is the average value of the working voltage within a preset time window, n is the voltage exponent, and f(SOH) is the decay function related to the healthy state SOH.

[0018] The electrochemical aging model was constructed by calibrating the model parameters through offline experiments. For example, by conducting accelerated aging experiments on supercapacitors at different constant temperatures and voltages, the pre-exponential factor can be obtained through fitting. The unit is the daily percentage decrease in SOH, and the activation energy. Joules per mole, voltage index The attenuation function f(SOH) is preferably a simple linear function, such as... ,in , This indicates that the aging rate decreases linearly with decreasing SOH. The basic aging process is determined by two core electrochemical stress factors, namely temperature and voltage, while aging itself also affects the aging rate.

[0019] In actual operation, the steps are as follows: Within a preset time window, such as the past 10 minutes, the casing temperature and operating voltage of the supercapacitor are continuously monitored and recorded. Assume that during this period, the average reading of the casing temperature sensor is 50°C, i.e., absolute temperature scale T = 323.15 Kelvin, and the average operating voltage is measured simultaneously. The voltage is 2.7V. The current health status value is obtained from the SOH estimation module, assumed to be SOH = 0.96. The collected data and preset model parameters are substituted into the formula for calculation, with the ideal gas constant R taken as 8.314 joules per mole Kelvin. Calculation results... This represents the predicted percentage decrease in daily SOH under the current stable operating conditions of 50℃ and 2.7V.

[0020] To represent and compensate for the additional aging caused by drastic temperature changes, in an optional embodiment, the calculation of the second time derivative of the shell temperature within a preset time window as a thermal shock factor, and the use of the thermal shock factor to correct the base aging rate to obtain the predicted aging rate for the next time step, includes: The absolute value of the second time derivative of the shell temperature within a preset time window is used as the thermal shock factor. ; The basic aging rate is expressed by the following formula. Corrected to the predicted aging rate : in, This is the thermal shock correction factor.

[0021] Continuous acquisition of shell temperature data, for example, recording the temperature value once per second, forms a time series T(t). To calculate the second time derivative, a numerical difference method is employed. For example, at time t, using the current temperature value T(t), the temperature value T(t-1) from the previous second, and the temperature value T(t-2) from the second before that, the value is calculated using the formula... The acceleration due to temperature is approximated, where the time interval is... The value is 1 second. Assuming the current temperature is 60°C, the temperature one second ago was 55°C, and the second before that was 54°C, then the second derivative is approximately 4 degrees Celsius per square second. Thermal shock factor. That is, the absolute value of the value, which is 4.

[0022] Thermal shock correction factor It is an experimentally calibrated parameter that represents the material's sensitivity to thermal stress, such as a preset value. Assuming the base aging rate is calculated from the electrochemical aging model. For daily decay .Will , and Substitute the values ​​into the corrected formula. The predicted aging rate can then be calculated. ,like Figure 3 The results indicate that the actual predicted aging rate is 60% higher than at stable temperatures due to the current dramatic temperature rise. This correction incorporates the physical aging mechanism of electrode structure damage caused by thermal expansion and contraction mismatch into the overall aging assessment.

[0023] S3. Based on the predicted aging rate and health status estimate, generate a voltage adjustment factor to delay electrolyte decomposition; combine the current power-priority or energy-priority operating mode of the supercapacitor, and obtain the reference cutoff voltage from the preset voltage reference-operating mode mapping table. The voltage adjustment factor K is adjusted using a pre-calibrated two-dimensional lookup table stored in flash memory. The two input axes of this lookup table are the normalized predicted aging rate (range 0 to 1) and the health status estimate (range 0.7 to 1). The values ​​in the table range from 0.85 to 1.0. For example, when the predicted aging rate is 0.8 and the health status is 0.82, the voltage adjustment factor K is adjusted to 0.91 using bilinear interpolation.

[0024] When switching to power priority mode, the corresponding reference cutoff voltage is read as 2.85V from the mapping table embedded in the program. When switching to energy priority mode, the corresponding reference cutoff voltage is read as 2.65V from the table.

[0025] In an optional embodiment, generating a voltage adjustment factor for delaying electrolyte decomposition based on the predicted aging rate and health status estimate includes: Calculate the predicted aging rate Compared with the preset aging rate target threshold Deviation between ; The voltage adjustment factor is generated using a proportional control strategy based on the health status estimate, according to the following formula. : in, The proportional gain coefficient is determined based on the estimated health status.

[0026] Preset an acceptable aging rate target threshold For example, based on the planned lifespan requirement, the daily SOH decay is set to not exceed The predicted aging rate will be calculated in real time. For example, the result obtained in the previous moment This is compared to the threshold. The deviation is calculated. This positive deviation indicates that the current aging rate is exceeding expectations and measures need to be taken to slow it down.

[0027] A proportional control strategy is adopted, wherein the proportional gain coefficient is... It is not a fixed value, but rather related to the state of health (SOH) of the supercapacitor. For example, This can be determined using a piecewise function or a lookup table: when SOH is between 100% and 90%. Percentage of SOH per 500 volts per day; when SOH is below 90%, Reduced to 350 to balance performance and lifespan at the end of the product's lifespan. Assuming a current SOH of 95%, then [the appropriate value is selected]. The voltage adjustment factor is calculated using a formula. Volts. The 0.02-volt adjustment factor is the recommended cutoff voltage reduction, which slows down the aging rate by reducing the operating voltage stress, bringing it back to near the target threshold.

[0028] In an optional embodiment, the step of obtaining the reference cutoff voltage from a preset voltage reference-operating mode mapping table, in conjunction with the current supercapacitor's power-priority or energy-priority operating mode, includes: When the operating mode is power priority mode, the reference cutoff voltage is the first preset ratio of the rated voltage; When the operating mode is energy priority mode, the reference cutoff voltage is a second preset ratio of the rated voltage, and the second preset ratio is lower than the first preset ratio.

[0029] Assume the rated voltage of the supercapacitor is 2.85V. The mapping table contains at least two modes. The first is the power priority mode, suitable for scenarios requiring millisecond-level response and instantaneous high-power throughput, such as primary frequency regulation of the power grid, with a first preset ratio of 98%. The second is the energy priority mode, suitable for scenarios that need to balance energy storage duration and long system lifespan operation, such as smoothing fluctuations in renewable energy generation or substation backup power, with a second preset ratio of 95%, which is lower than the first preset ratio.

[0030] When a reference cutoff voltage needs to be determined, the current operating mode command is queried. For example, the energy management system of a grid-connected energy storage system monitors the grid frequency and voltage status in real time. When a sudden increase in grid load causes a frequency drop, requiring the supercapacitor to provide a rapid frequency response, a command is issued to switch the supercapacitor system to power-priority mode. The controller queries the mapping table to find the ratio 0.98 corresponding to power-priority mode. The reference cutoff voltage is calculated as the rated voltage multiplied by this ratio, which is 2.793V. Conversely, when the grid is operating smoothly and the supercapacitor is only used to smooth short-term power fluctuations from wind and solar power generation or is in hot standby mode, it switches to energy-priority mode. The controller will then query the ratio 0.95 and calculate the reference cutoff voltage as 2.7075V. In this way, a balance between performance and lifespan is achieved between different application requirements.

[0031] S4. The reference cutoff voltage is adjusted using the voltage adjustment factor to obtain the target cutoff voltage, and the charging and discharging process of the supercapacitor is controlled in a closed loop according to the target cutoff voltage.

[0032] Multiply the reference cutoff voltage Vreference obtained from the previous table lookup by the voltage adjustment factor Kadjustment to obtain the target cutoff voltage Vtarget = Vreference × Kadjustment. For example, in power priority mode, if Vreference is 2.85 volts and Kadjustment is 0.91, then Vtarget is 2.59 volts. This Vtarget value is set as the voltage setpoint for the bidirectional DC-DC converter charging control loop. During charging, the controller compares the actual voltage of the supercapacitor with Vtarget in real time. Once the actual voltage reaches Vtarget, the controller sets the charging current command to zero, thereby terminating the charging process.

[0033] In an optional embodiment, adjusting the reference cutoff voltage using the voltage adjustment factor to obtain the target cutoff voltage includes: Subtract the voltage adjustment factor from the reference cutoff voltage to obtain the initial target cutoff voltage; The initial target cutoff voltage is compared with preset upper and lower voltage protection values, and the initial target cutoff voltage is limited to the range formed by the upper and lower protection values ​​to obtain the target cutoff voltage.

[0034] The abstract control quantity obtained from the previous calculations is transformed into an executable voltage setpoint. Assuming the current mode is energy-priority, the reference cutoff voltage is 2.7075V. Simultaneously, the voltage adjustment factor calculated by the aging rate control module... The value is 0.02V. The initial target cutoff voltage is obtained by calculating the values ​​of these two values. V. When an excessively rapid aging rate is detected, protection is applied by actively reducing the charging cutoff voltage.

[0035] To ensure the supercapacitor always operates within an absolutely safe voltage range, maximum and minimum protection voltages are preset at the hardware or software level. For example, the maximum voltage limit protection value is set to 2.85V as specified by the manufacturer, and the minimum protection value is set to 2.2V required to guarantee basic performance. The calculated initial target cutoff voltage of 2.6875V is compared with the safe voltage range consisting of 2.2V and 2.85V. Since 2.6875V falls within this range, it is adopted as the target cutoff voltage. If, in some extreme cases, the calculated initial value exceeds this range, such as when aging calculations necessitate a reduction to 2.1V, it will be forcibly limited to 2.2V to avoid excessive performance suppression. The adjusted and safety-limited target cutoff voltage value is sent to the charging control unit as the maximum voltage target for this charging cycle.

[0036] In the second embodiment, the present invention also proposes a temperature-responsive capacitor voltage dynamic control system, comprising the following modules: The update module is used to obtain the real-time operating voltage, operating current and shell temperature of the supercapacitor; by analyzing the voltage and current response during the charging and discharging switching transient process, the impedance information of at least two characteristic frequency points is extracted, the high-frequency equivalent series resistance and the low-frequency equivalent series resistance are calculated, and the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance is used to update the health status estimate of the supercapacitor. The correction module is used to calculate the basic aging rate based on the health status estimate, real-time operating voltage and shell temperature; at the same time, it calculates the second time derivative of the shell temperature within a preset time window as a thermal shock factor, and uses the thermal shock factor to correct the basic aging rate to obtain the predicted aging rate for the next time step. The query module is used to generate a voltage adjustment factor for delaying electrolyte decomposition based on the predicted aging rate and health status estimate; and to obtain the reference cutoff voltage from the preset voltage reference-operating mode mapping table in combination with the current power-priority or energy-priority operating mode of the supercapacitor. The control module is used to adjust the reference cutoff voltage using the voltage adjustment factor to obtain the target cutoff voltage, and to perform closed-loop control of the charging and discharging process of the supercapacitor based on the target cutoff voltage.

[0037] In a third embodiment, the present invention also proposes a temperature-responsive capacitor voltage dynamic control terminal, the control terminal comprising at least a memory and a processor, wherein the memory stores a temperature-responsive capacitor voltage dynamic control program, and when the program is executed by the processor, it implements the steps of the control method described in the first embodiment.

[0038] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A method for dynamic control of capacitor voltage based on temperature response, characterized in that, Includes the following steps: The real-time operating voltage, operating current, and shell temperature of the supercapacitor are obtained; by analyzing the voltage and current response during the charging and discharging switching transient process, impedance information at least two characteristic frequency points is extracted, the high-frequency equivalent series resistance and the low-frequency equivalent series resistance are calculated, and the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance is used to update the estimated health status of the supercapacitor. The basic aging rate is calculated based on the health status estimate, real-time operating voltage, and housing temperature. Simultaneously, the second time derivative of the shell temperature within a preset time window is calculated as a thermal shock factor, and the basic aging rate is corrected using the thermal shock factor to obtain the predicted aging rate for the next time step. Based on the predicted aging rate and health status estimate, a voltage adjustment factor is generated to delay electrolyte decomposition; combined with the current power-priority or energy-priority operating mode of the supercapacitor, the reference cutoff voltage is obtained by querying the preset voltage reference-operating mode mapping table. The reference cutoff voltage is adjusted using the voltage adjustment factor to obtain the target cutoff voltage, and the charging and discharging process of the supercapacitor is controlled in a closed loop based on the target cutoff voltage.

2. The method according to claim 1, characterized in that, The calculation of the second time derivative of the shell temperature within a preset time window as a thermal shock factor, and the use of the thermal shock factor to correct the basic aging rate to obtain the predicted aging rate for the next time step, includes: The absolute value of the second time derivative of the shell temperature within a preset time window is used as the thermal shock factor. ; The basic aging rate is expressed by the following formula. Corrected to the predicted aging rate : in, This is the thermal shock correction factor.

3. The method according to claim 1, characterized in that, The step of generating a voltage adjustment factor to delay electrolyte decomposition based on the predicted aging rate and health status estimate includes: Calculate the deviation between the predicted aging rate and the preset aging rate target threshold. ; The voltage adjustment factor is generated using the following formula. : ; in, The proportional gain coefficient is determined based on the estimated health status.

4. The method according to any one of claims 1-3, characterized in that, The step of obtaining the reference cutoff voltage from a preset voltage reference-operating mode mapping table, based on the current supercapacitor's power-priority or energy-priority operating mode, includes: When the operating mode is power priority mode, the reference cutoff voltage is the first preset ratio of the rated voltage; When the operating mode is energy priority mode, the reference cutoff voltage is a second preset ratio of the rated voltage, and the second preset ratio is lower than the first preset ratio.

5. The method according to any one of claims 1-3, characterized in that, The step of adjusting the reference cutoff voltage using the voltage adjustment factor to obtain the target cutoff voltage includes: Subtract the voltage adjustment factor from the reference cutoff voltage to obtain the initial target cutoff voltage; The initial target cutoff voltage is compared with preset upper and lower voltage protection values, and the initial target cutoff voltage is limited to the range formed by the upper and lower protection values ​​to obtain the target cutoff voltage.

6. A temperature-responsive capacitor voltage dynamic control system, characterized in that, Includes the following modules: The update module is used to obtain the real-time operating voltage, operating current and shell temperature of the supercapacitor; by analyzing the voltage and current response during the charging and discharging switching transient process, the impedance information of at least two characteristic frequency points is extracted, the high-frequency equivalent series resistance and the low-frequency equivalent series resistance are calculated, and the weighted difference between the high-frequency equivalent series resistance and the low-frequency equivalent series resistance is used to update the health status estimate of the supercapacitor. The correction module is used to calculate the basic aging rate based on the estimated health status, real-time operating voltage, and housing temperature. Simultaneously, the second time derivative of the shell temperature within a preset time window is calculated as a thermal shock factor, and the basic aging rate is corrected using the thermal shock factor to obtain the predicted aging rate for the next time step. The query module is used to generate a voltage adjustment factor for delaying electrolyte decomposition based on the predicted aging rate and health status estimate; and to obtain the reference cutoff voltage from the preset voltage reference-operating mode mapping table in combination with the current power-priority or energy-priority operating mode of the supercapacitor. The control module is used to adjust the reference cutoff voltage using the voltage adjustment factor to obtain the target cutoff voltage, and to perform closed-loop control of the charging and discharging process of the supercapacitor based on the target cutoff voltage.

7. The system according to claim 6, characterized in that, The calculation of the second time derivative of the shell temperature within a preset time window as a thermal shock factor, and the use of the thermal shock factor to correct the basic aging rate to obtain the predicted aging rate for the next time step, includes: The absolute value of the second time derivative of the shell temperature within a preset time window is used as the thermal shock factor. ; The basic aging rate is expressed by the following formula. Corrected to the predicted aging rate : in, This is the thermal shock correction factor.

8. The system according to claim 6, characterized in that, The step of generating a voltage adjustment factor to delay electrolyte decomposition based on the predicted aging rate and health status estimate includes: Calculate the deviation between the predicted aging rate and the preset aging rate target threshold. ; The voltage adjustment factor is generated using the following formula. : ; in, The proportional gain coefficient is determined based on the estimated health status.

9. The system according to any one of claims 6-8, characterized in that, The step of obtaining the reference cutoff voltage from a preset voltage reference-operating mode mapping table, based on the current supercapacitor's power-priority or energy-priority operating mode, includes: When the operating mode is power priority mode, the reference cutoff voltage is the first preset ratio of the rated voltage; When the operating mode is energy priority mode, the reference cutoff voltage is a second preset ratio of the rated voltage, and the second preset ratio is lower than the first preset ratio.

10. A temperature-responsive capacitor voltage dynamic control terminal, characterized in that, The control terminal includes at least a memory and a processor, wherein the memory stores a dynamic control program for capacitor voltage based on temperature response, and when the program is executed by the processor, it implements the steps of the control method as described in any one of claims 1 to 5.

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