Self-adaptive charging and discharging control system of capacitor energy storage system

Abstract

A self-adaptive charging and discharging control system for a capacitor energy storage system belongs to the technical field of power grid charging and discharging control, and comprises a state sensing module, a dynamic calculation module, a state storage module, a state storage module, a state storage module, a state storage module and a state storage module, and is characterized in that the state sensing module acquires state acquisition data of a capacitor in real time through a current sensor, a temperature sensor and a voltage sensor; the polarization capacitance, the equivalent series resistance and the charge state of the capacitor are calculated through a dynamic quantization algorithm, and the self-adaptive control module adjusts the magnitude and the direction of charging and discharging current through a closed-loop feedback algorithm according to the polarization capacitance, the equivalent series resistance and the charge state output by the dynamic calculation module; the safety protection module triggers a hardware protection mechanism to cut off a charging and discharging loop based on overcurrent, over-temperature and overvoltage data collected by the state sensing module, and self-adaptive charging and discharging of the capacitor energy storage system are achieved through dynamic quantization of the polarization state, real-time compensation of internal resistance loss, high-precision updating of the charge state and closed-loop feedback control.

Description

Technical Field

[0001] This invention relates to the field of power grid charging and discharging control technology, specifically an adaptive charging and discharging control system for a capacitor energy storage system. Background Technology

[0002] Capacitor energy storage systems are widely used in urban rail transit regenerative braking, power grid frequency regulation, and energy recovery in new energy vehicles due to their high power density and fast charging and discharging speed. Their core requirement is to achieve efficient and safe charging and discharging control under complex operating conditions (high current, wide temperature range)—maximizing energy recovery efficiency while minimizing polarization losses and thermal damage, thus extending system lifespan.

[0003] Traditional capacitor energy storage systems rely on a static strategy of "rated current + fixed temperature threshold," meaning the charging and discharging current is set based on the capacitor's rated parameters (e.g., rated current 100A, upper temperature limit 60℃), thus neglecting the impact of dynamic changes in operating conditions on the system state. As the new energy industry demands increasing adaptability from energy storage systems, static control strategies are insufficient to meet practical needs, necessitating adaptive control technology based on dynamic state perception.

[0004] Therefore, those skilled in the art provide an adaptive charging and discharging control system for a capacitor energy storage system to solve the problems mentioned in the background art. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide an adaptive charging and discharging control system for a capacitor energy storage system, so as to achieve accurate quantification of polarization intensity, dynamic quantification of internal resistance loss, and accurate updating and closed-loop feedback of state of charge.

[0006] To address the above problems, the present invention provides the following technical solution: An adaptive charge and discharge control system for a capacitor energy storage system, comprising: The status sensing module is configured to collect status data of the capacitor in real time, including charging and discharging current, core temperature and terminal voltage data, through current sensor, temperature sensor and voltage sensor. The dynamic calculation module is configured to integrate the state acquisition data collected by the state perception module and calculate the polarization capacitance, equivalent series resistance and state of charge of the capacitor through a dynamic quantization algorithm. The adaptive control module is configured to adjust the magnitude and direction of the charging and discharging current through a closed-loop feedback algorithm based on the polarization capacitance, the equivalent series resistance, and the state of charge output by the dynamic calculation module. The safety protection module is configured to trigger a hardware protection mechanism to cut off the charging and discharging circuit based on the overcurrent, overtemperature, and overvoltage data collected by the state sensing module. The dynamic calculation module of the adaptive charge-discharge control system for capacitor energy storage systems includes: The polarization intensity calculation submodule is configured to combine real-time current and temperature data, and through coupled calculation of relative current intensity and temperature deviation, quantify the polarization state of the capacitor and output the polarization capacitance. The equivalent internal resistance calculation submodule is configured to quantify the internal resistance loss of the capacitor and output the equivalent series resistance based on the polarization capacitance and combined with the temperature deviation, through nonlinear fitting of the polarization relative value and temperature range. The state of charge update submodule is configured to integrate ideal charge and discharge quantities and internal resistance losses, and predict the remaining state of charge of the capacitor at the next moment through a dynamic compensation algorithm.

[0007] Further: The calculation logic of the polarization intensity calculation submodule is as follows: The current sensor collects real-time charging and discharging current, calculates the first ratio of charging and discharging current to rated current, and calculates the current correction term for polarization impact intensity under the influence of the product of the experimentally calibrated current influence coefficient. The capacitor temperature is collected in real time by a temperature sensor, and the temperature deviation between the capacitor temperature and the preset reference temperature is calculated. Under the influence of the first temperature influence coefficient calibrated in the experiment, the first temperature correction term for the polarization dissipation capability is calculated. The current correction term and the first temperature correction term are weighted and coupled together, and multiplied by the initial polarization capacitance to output the real-time polarization capacitance.

[0008] Further: The calculation logic of the equivalent internal resistance calculation submodule is as follows: Based on the polarization capacitance output by the polarization intensity calculation submodule, the second ratio of the polarization capacitance to the initial polarization capacitance is calculated, and the polarization correction term for the internal resistance blocking effect is calculated under the influence of the product of the polarization capacitance influence coefficient calibrated in the experiment. The temperature deviation is calculated based on the polarization intensity calculation submodule, and the second temperature correction term for the effect of temperature on ohmic loss is calculated under the influence of the temperature deviation multiplied by the experimentally calibrated second temperature influence coefficient. The fitting results of the polarization correction term and the second temperature correction term are coupled and multiplied with the reference equivalent series resistance to output the real-time equivalent series resistance.

[0009] Further: The calculation logic of the state of charge update submodule is as follows: Based on the charging and discharging current collected by the current sensor, the ratio of the charging and discharging current multiplied by the preset control cycle to the total capacitance is calculated, and the ideal charging and discharging amount without loss is obtained. The internal resistance loss energy is obtained by multiplying the equivalent series resistance, the charging and discharging current, and the control period. The internal resistance loss energy is then divided by the product of the rated voltage and the total capacitance to obtain the internal resistance loss. The state of charge at the previous moment, the ideal charge / discharge quantity, and the internal resistance loss are dynamically coupled to output the updated state of charge at the next moment.

[0010] Furthermore: the adaptive control module includes: The current adjustment unit adjusts the duty cycle of the charging and discharging current via a PWM signal; The closed-loop feedback unit adjusts the current influence coefficient based on the state of charge output by the state of charge update submodule, and feeds it back to the polarization intensity calculation submodule to update and calculate the polarization capacitance at the next moment. Based on the polarization capacitance at the next moment, the unit dynamically adjusts the current sampling strategy at the next moment.

[0011] Furthermore: the adjustment of the current influence coefficient is based on the polarization characteristics of a pre-set state-of-charge range, specifically in the following manner: When the state of charge is in the low state of charge range (state of charge <30%), it reflects that the charge density on the electrode surface is low and the polarization effect is weak. The current influence coefficient is taken as 0.001. When the state of charge is in the medium state of charge range (30%≤state of charge≤80%), it reflects that the charge density on the electrode surface is moderate, and the polarization effect increases linearly with the state of charge. The current influence coefficient is taken as 0.005. When the state of charge is in the high state of charge range (state of charge > 80%), it reflects that the charge density on the electrode surface is close to saturation, and the polarization effect is sharply enhanced. The current influence coefficient is taken as 0.01.

[0012] Further: The current sampling strategy is specifically as follows: If the polarization capacitance at the next moment is greater than the initial polarization capacitance × 1.2 (strong polarization), it indicates that the polarization loss is too large, and the charging and discharging current needs to be reduced to avoid overheating and capacity decay. If the polarization capacitance at the next moment is less than the initial polarization capacitance × 0.8 (weak polarization), it indicates that the polarization loss is small, and the charging and discharging current needs to be increased to improve the charging and discharging efficiency. If the initial polarization capacitance × 0.8 ≤ the polarization capacitance at the next moment ≤ the initial polarization capacitance × 1.2 (medium polarization), then the current charge / discharge current is maintained to balance efficiency and loss.

[0013] Furthermore: the security protection module includes: The overcurrent protection unit triggers a relay to cut off the circuit when the current collected by the current sensing unit exceeds 1.5 times the rated current. The over-temperature protection unit activates the cooling fan and reduces the charging and discharging current when the core temperature collected by the temperature sensing unit exceeds 60°C. The overvoltage protection unit stops charging and starts the discharge circuit when the voltage collected by the voltage sensing unit exceeds 1.1 times the rated voltage.

[0014] The effects of the above solution are as follows: 1. The polarization intensity calculation submodule in this invention achieves precise quantification of polarization intensity through coupled calculation of relative current intensity and temperature deviation. Specifically, it adjusts the polarization capacitor based on the relative current intensity—that is, the larger the current, the larger the increase in polarization capacitor—to automatically reduce the current under high charge conditions (avoiding overcharge polarization), reducing polarization losses and achieving dynamic compensation for current polarization impact. Furthermore, it adjusts the polarization capacitor based on the temperature deviation—that is, the higher the temperature, the larger the reduction in polarization capacitor. In the mid-temperature range (25-60℃), it utilizes the polarization dissipation space created by the increased temperature to automatically increase the current, improving charging efficiency and thus satisfying the adaptive utilization of temperature-induced polarization dissipation.

[0015] 2. The equivalent internal resistance calculation submodule in this invention achieves dynamic quantification of internal resistance loss through the coupled calculation of the relative value of polarization capacitance and temperature deviation. Specifically, the internal resistance is adjusted according to the relative value of polarization capacitance (the stronger the polarization, the larger the increase in internal resistance), automatically reducing the current under high current conditions (avoiding excessive heat loss), reducing the error in internal resistance loss estimation, and realizing real-time compensation for polarization internal resistance blockage. Furthermore, the internal resistance is differentiated into medium-temperature and high-temperature ranges based on the temperature deviation (internal resistance decreases at medium temperatures and increases at high temperatures), automatically increasing the current in the medium-temperature range (utilizing the low-loss space due to reduced internal resistance) and automatically decreasing the current in the high-temperature range (avoiding overheating and burnout), extending the system lifespan and achieving range adaptation to temperature-dependent internal resistance changes.

[0016] 3. The equivalent internal resistance calculation submodule in this invention achieves accurate updating and closed-loop feedback of the state of charge (SOC) through the coupled calculation of ideal charge / discharge quantity and internal resistance loss. Specifically, internal resistance loss is converted into a reduction in SOC (the greater the current and the greater the internal resistance, the greater the reduction), reducing the error in SOC estimation and achieving energy compensation for internal resistance loss. The updated SOC is then fed back, automatically reducing the current during high SOC (to avoid overcharging) and automatically increasing the current during low SOC (to avoid undercharging), forming a closed loop of "current → polarization → internal resistance → SOC → current," thereby significantly improving charging and discharging efficiency. Attached Figure Description

[0017] Figure 1 This is a system flowchart illustrating the adaptive charge and discharge control of the capacitor energy storage system of the present invention. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0019] Example 1, please refer to Figure 1 An adaptive charge and discharge control system for a capacitor energy storage system, comprising: The status sensing module is configured to collect status data of the capacitor in real time, including charging and discharging current, core temperature and terminal voltage data, through current sensor, temperature sensor and voltage sensor. The dynamic calculation module is configured to integrate the state acquisition data collected by the state perception module and calculate the polarization capacitance, equivalent series resistance and state of charge of the capacitor through a dynamic quantization algorithm. The adaptive control module is configured to adjust the magnitude and direction of the charging and discharging current through a closed-loop feedback algorithm based on the polarization capacitance, equivalent series resistance and state of charge output by the dynamic calculation module. The safety protection module is configured to trigger a hardware protection mechanism to cut off the charging and discharging circuit based on overcurrent, overtemperature, and overvoltage data collected by the status sensing module. The dynamic calculation module of the adaptive charge-discharge control system for capacitor energy storage systems includes: The polarization intensity calculation submodule is configured to combine real-time current and temperature data, and through coupled calculation of relative current intensity and temperature deviation, quantify the polarization state of the capacitor and output the polarization capacitance. The equivalent internal resistance calculation submodule is configured to quantify the internal resistance loss of the capacitor and output the equivalent series resistance based on the polarization capacitance and combined with the temperature deviation, through nonlinear fitting of the polarization relative value and temperature range. The state of charge update submodule is configured to integrate ideal charge and discharge quantities and internal resistance losses, and predict the remaining state of charge of the capacitor at the next moment through a dynamic compensation algorithm.

[0020] In the above embodiments, the state perception module uses multi-sensor fusion technology to achieve comprehensive real-time acquisition of key state parameters of the capacitor, providing a data foundation for subsequent dynamic calculation and control; the dynamic calculation module, through the collaboration of three sub-modules—polarization intensity calculation, equivalent internal resistance calculation, and state of charge update—achieves dynamic modeling and real-time estimation of the internal state of the capacitor; the adaptive control module, based on the state parameters output by the dynamic calculation module, uses a closed-loop feedback mechanism to achieve precise regulation of the charging and discharging current, improving system energy efficiency and safety; and the safety protection module, as the last line of defense at the hardware level, ensures that the system can quickly disconnect the circuit under abnormal operating conditions to prevent equipment damage.

[0021] The status sensing module employs high-precision current sensors (such as Hall sensors), temperature sensors (such as PT100), and voltage sensors, with a sampling frequency of no less than 1kHz to ensure data real-time performance and accuracy. The dynamic calculation module runs on an embedded processor (such as ARM Cortex-M4), and the control cycle can be set to 10ms to meet real-time control requirements. The adaptive control module adjusts the charging and discharging current through PWM modulation technology, supporting bidirectional energy flow. The safety protection module uses a combination of hardware comparators and relays, with a response time of less than 10ms, ensuring rapid and reliable protection actions.

[0022] In summary, this embodiment constructs a complete adaptive charging and discharging control system for capacitor energy storage system through modular design and multi-sensor information fusion. It realizes intelligent management of the entire process from state perception, dynamic modeling, closed-loop control to safety protection, and provides technical support for the efficient and safe operation of capacitors under complex working conditions.

[0023] Example 2: Based on Example 1, the calculation logic of the polarization intensity calculation submodule provided in this embodiment of the invention is as follows: The charging and discharging current is collected in real time by a current sensor, the first ratio of the charging and discharging current to the rated current is calculated, and the current correction term of the current on the polarization impact intensity is calculated under the influence of the product of the experimentally calibrated current influence coefficient. The capacitor temperature is collected in real time by a temperature sensor, and the temperature deviation between the capacitor temperature and the preset reference temperature is calculated. Under the influence of the first temperature influence coefficient calibrated in the experiment, the first temperature correction term for the polarization dissipation capability is calculated. The current correction term and the first temperature correction term are weighted and coupled together, and then multiplied by the initial polarization capacitance to output the real-time polarization capacitance.

[0024] The formula for calculating the polarization capacitance is as follows: ; In the formula: C p(t) C is the polarization capacitance at time t, reflecting the dynamic capacitance value of the capacitor's internal polarization effect. p0 The initial polarization capacitance is the reference value of the capacitor's polarization capacitance at the time of manufacture, which can be measured through factory testing. 'a' is the current influence coefficient, and 'I' is the initial polarization capacitance. (t) The charging and discharging current at time t can be measured in real time by a current sensor (positive for charging, negative for discharging), I. rated The rated current is the maximum design operating current of the capacitor, determined by the product specifications. b is the first temperature influence coefficient, and T... (t) The capacitor temperature at time t can be measured in real time using a temperature sensor. refThe reference temperature is the standard temperature for capacitor performance testing, where time t represents the current real-time moment.

[0025] In the above embodiments, the polarization intensity calculation submodule achieves dynamic correction of the polarization capacitance through real-time correction of two factors: current and temperature, and the introduction of a current influence coefficient a and a first temperature influence coefficient b. Specifically: On the one hand, the current correction term This reflects the enhancing effect of large current on polarization intensity. During capacitor charging and discharging, current passing through the electrode-electrolyte interface generates double-layer polarization (charge accumulation at the interface) and Faraday polarization (charge transfer caused by electrochemical reactions). The larger the current, the more charge passes through the interface per unit time, and the faster the accumulation rate of polarization charge. Therefore, the polarization capacitance C at time t increases. p(t) It will increase with the increase of current, at the rated current I rated Within the range (I) (t) ≤I rated The accumulation of polarization charge is approximately linearly related to the current, and exceeds the rated current I. rated Afterwards, the polarization effect enters the nonlinear saturation region, but through... Normalization ensures that the correction terms are within a reasonable range; On the other hand, the first temperature correction term This reflects the promoting effect of temperature increase on polarization dissipation. Increased temperature accelerates the dissipation of polarization charges (increased thermal motion makes it easier for charges to detach from the interface). Therefore, the polarization capacitance C at time t... p(t) The polarization capacitance C decreases with increasing temperature, and conversely, decreasing temperature inhibits the dissipation of polarization charge. At time t, the polarization capacitance C... p(t) Within the operating temperature range, the dissipation rate of polarization charge exhibits an approximately linear relationship with temperature. However, beyond the operating temperature range, the capacitor performance deteriorates sharply. This invention, however, addresses this issue by... The difference correction is used to ensure that the correction term reflects the effect of actual temperature deviation on polarization; Thus, this model combines physical mechanisms with experimental calibration, achieving high-precision quantification of polarization states.

[0026] Among them, the current influence coefficient 'a' and the first temperature influence coefficient 'b' are both empirical coefficients calibrated through experiments, and need to be determined in conjunction with the specific type of capacitor (such as supercapacitor, electrolytic capacitor) and the application scenario. The steps are as follows: Regarding the current influence coefficient α: a fixed temperature is set at (25℃), and different charging and discharging currents I are set. (t) (e.g., 0.1I) rated 0.5I rated I ratedAt each current, the polarization capacitance after stabilization was measured using an LCR meter, and the polarization capacitance was plotted against the line. The relationship curve is obtained, and the current influence coefficient 'a' (slope) is obtained through linear fitting. Example: If the current increases from 0 to I... rated At that time, C p From C p0 Increased to 1.1C p0 Then the current influence coefficient a = 0.1.

[0027] For the first temperature influence coefficient b: With a fixed current of 0 (to avoid current interference), different capacitor temperatures T are set. (t) (e.g., -10℃, 0℃, 25℃, 40℃, 60℃), at each temperature, the stable C value is measured using an LCR meter. p Value, plot C p and The relationship curve is used to obtain the first temperature influence coefficient b (the absolute value of the slope) through linear fitting. Example: If the temperature rises from 25℃ to 60℃, C p From C p0 Decreased to 0.93C p0 Therefore, the first temperature influence coefficient b = 0.07 / 35 = 0.002 (for every 1℃ increase in temperature, C...). p (Decrease of 0.2%).

[0028] In summary, the polarization intensity calculation submodule in this embodiment achieves dynamic estimation of polarization capacitance by coupling the effects of current and temperature, providing accurate polarization state input for subsequent internal resistance calculation, state of charge update and current control, and improving the system's adaptability to changes in operating conditions.

[0029] Example 3: Based on Example 2, the calculation logic of the equivalent internal resistance calculation submodule provided in this embodiment of the invention is as follows: Based on the polarization capacitance output by the polarization intensity calculation submodule, the second ratio of the polarization capacitance to the initial polarization capacitance is calculated. Under the influence of the product of the polarization capacitance influence coefficient calibrated in the experiment, the polarization correction term for the internal resistance blocking effect of polarization is calculated. The temperature deviation is calculated based on the polarization intensity calculation submodule, and the second temperature correction term for the effect of temperature on ohmic loss is calculated under the influence of the temperature deviation multiplied by the experimentally calibrated second temperature influence coefficient. The fitting results of the polarization correction term and the second temperature correction term are coupled and multiplied with the reference equivalent series resistance to output the real-time equivalent series resistance.

[0030] The formula for calculating the real-time equivalent series resistance is as follows: ; In the formula: ESR(t) Let be the equivalent series resistance at time t, reflecting the dynamic change of the capacitor's internal resistance. ESR0 is the reference equivalent series resistance at the reference temperature, indicating the capacitor's resistance at the reference temperature T. ref The internal resistance at a temperature below 25°C can be measured through factory testing. c is the second temperature influence coefficient, determined experimentally (e.g., 0.005, meaning that for every 1°C increase in temperature, the ESR increases). (t) Increase by 0.5%), the specific calculation formula is as follows: And in the formula, Reflects the direction of ESR change. The sign of c reflects the direction of temperature change, and the correlation between the ESR change direction and the temperature change direction (positive / negative correlation) is also represented by c. d is the polarization capacitance influence coefficient, which is also an empirical coefficient calibrated experimentally. The specific calibration process involves fixing the temperature (25℃) and setting different charging and discharging currents I. (t) (e.g., 0.1I) rated 0.5I rated I rated For each current, first use Calculate the polarization capacitance C at time t. p(t) Then, use an LCR meter to measure the stabilized ESR value and plot the ESR versus... The relationship curve is used to obtain the polarization capacitance influence coefficient d (slope) through linear fitting. Example: If C p(t) From C p0 Increase to 1.1C p0 When ESR increases from ESR0 to 1.02ESR0, the polarization capacitance influence coefficient d = 0.02 (for every 1% increase in C). p ESR increased by 0.02%.

[0031] In the above embodiments, the equivalent internal resistance calculation submodule introduces the relative value of the polarization capacitance. and temperature deviation term This enables real-time dynamic estimation of internal resistance; among which, the polarization correction term... The increase in internal resistance caused by enhanced polarization was captured, and the second temperature correction term was used. The model distinguishes between the decreasing internal resistance in the mid-temperature region and the increasing internal resistance in the high-temperature region, making the model more closely reflect actual physical changes.

[0032] The calibration method for the second temperature influence coefficient c is as follows: Under zero current conditions, the ESR values ​​at different temperatures are measured, and c is obtained through linear fitting; the calibration method for the polarization capacitance influence coefficient d is as follows: At a constant temperature, different polarization capacitances are obtained by changing the current, and the corresponding ESR is measured. The coefficient d is obtained through fitting; the sign and magnitude of the coefficient reflect the sensitivity and direction of the internal resistance to temperature and polarization changes, and need to be determined through experimental data. Furthermore, the sign of the second temperature influence coefficient c is a quantitative result of the physical characteristics of the capacitor's internal resistance, and its relationship with the effect of temperature on ESR can be summarized as follows: The capacitor temperature T at time t (t) Reference temperature T ref When the second temperature influence coefficient c is negative, a decrease in temperature leads to an increase in ESR, and the second temperature correction term... It is a positive number; Reference temperature T ref The capacitor temperature T at time t ≤ (t) At temperatures below 60℃: the second temperature influence coefficient c is negative; as temperature increases, ESR decreases, and the second temperature correction term... It is a negative number; The capacitor temperature T at time t (t) At ≥60℃: the second temperature influence coefficient c is positive; as temperature increases, ESR increases, and the second temperature correction term... It is a positive number.

[0033] Based on the above, it can be understood that the sign of the second temperature influence coefficient c is not fixed, but varies with the temperature range. Essentially, it transforms the temperature sensitivity of the ESR into a calculable mathematical coefficient, ensuring... It can accurately reflect the changes in internal resistance and loss at different temperatures.

[0034] Furthermore, although both the first temperature influence coefficient b and the second temperature influence coefficient c are temperature-related coefficients, the first temperature influence coefficient b affects the polarization charge storage capacity (polarization capacitance C at time t). p(t) The first temperature coefficient reflects the logic of "temperature → polarization dissipation → capacitance change"; the second temperature influence coefficient c acts on the inherent resistance value of the ohm (such as the metallic resistance of the electrode, the ionic resistance of the electrolyte), reflecting the logic of "temperature → material resistance characteristics → internal resistance change". These two belong to different physical processes, therefore they must be quantified separately using different coefficients.

[0035] In summary, the equivalent internal resistance calculation submodule of this embodiment achieves high-precision dynamic estimation of capacitor internal resistance through a two-factor coupling model, providing key parameters for loss compensation in state of charge updates, and also providing a basis for current limiting and thermal management in adaptive control.

[0036] Example 4: Based on Example 3, the calculation logic of the state of charge update submodule provided in this embodiment of the invention is as follows: Based on the charging and discharging current collected by the current sensor, the ratio of the charging and discharging current multiplied by the pre-set control cycle to the total capacitance is calculated, and the ideal charging and discharging amount under lossless conditions is obtained. The internal resistance loss energy is obtained by multiplying the equivalent series resistance, the charging and discharging current and the control period, and then dividing the internal resistance loss energy by the product of the rated voltage and the total capacitance to obtain the internal resistance loss. The state of charge, ideal charge / discharge, and internal resistance loss of the previous moment are dynamically coupled to output the updated state of charge for the next moment.

[0037] The updated real-time state of charge calculation formula is as follows: C total(t) =C0+C p(t) ; ; In the formula: SOC (t+1) State of charge (SOC) at time t+1 reflects the proportion of remaining charge to the rated capacity of the capacitor. (t) Δt represents the state of charge (SOC) at time t, specifically the SOC value of the previous time step, obtained from historical data or initial measurements. Δt is the control period; for example, a sampling interval of 10ms constitutes one period, which can be set according to specific control requirements. C total(t) The total capacitance, the sum of the static capacitance and the polarization capacitance, reflects the actual energy storage capacity of the capacitor. C0 is the static capacitance, and V... rated Rated voltage, representing the maximum design voltage of the capacitor, is determined by the product specification sheet.

[0038] In the above embodiments, the calculation of the state of charge (SOC) update submodule is a real-time calculation model for the SOC of the battery / capacitor. Essentially, it couples the "ideal charge / discharge amount" with the "actual internal resistance loss," thereby achieving dynamic correction of the SOC. This model not only considers the ideal charge / discharge amount but also compensates for energy loss caused by internal resistance heating, significantly improving the accuracy of SOC estimation, especially under high temperature and high current conditions. This allows for precise quantification of the capacitor's remaining energy, providing a core state signal for the closed-loop feedback of the charge / discharge strategy. Ideal charge / discharge It provides "energy changes without loss", thus showing the energy changes during charging (I (t) >0) SOC (t+1) Increase, during discharge (I) (t) <0)SOC (t+1) Reduced to the actual SOC (t+1) Updates provide benchmarks; Internal resistance loss correction term It compensates for the bias of "ideal model ignoring losses"—when current or internal resistance increases, the loss correction term increases, and the SOC... (t+1) Significant reduction (e.g., at a high current of 150A, the loss correction term increases from 0.05 to 0.13), avoiding the "theoretical SOC" limitation. (t+1) The risk of over-release, which is "high but with low actual energy".

[0039] Among them, the static capacitance C0 is an inherent parameter of the capacitor, which can be obtained from the manufacturer's specifications or through offline measurement; the total capacitance C total(t) The dynamic change with polarization state reflects the time-varying nature of the capacitor's actual energy storage capacity; the internal resistance loss term converts Joule heat loss into an equivalent reduction in the state of charge, achieving closed-loop correction at the energy level; the control period Δt needs to be set according to the trade-off between system response speed and calculated load.

[0040] In summary, the state of charge update submodule in this embodiment achieves real-time high-precision estimation of the state of charge through dynamic total capacitance and internal resistance loss compensation, providing accurate state feedback for the adaptive control module and serving as a core link in forming a "sensing-computation-control" closed loop.

[0041] Example 5: Based on Example 4, the adaptive control module provided in this embodiment of the invention includes: The current adjustment unit adjusts the duty cycle of the charging and discharging current through a PWM signal; The closed-loop feedback unit adjusts the current influence coefficient based on the state of charge (SOC) output from the SOC update submodule. When the state of charge is in the low state of charge range, it reflects that the charge density on the electrode surface is low and the polarization effect is weak, and the current influence coefficient is taken as 0.001. When the state of charge is in the intermediate state of charge range, it reflects that the charge density on the electrode surface is moderate, and the polarization effect increases linearly with the state of charge. The current influence coefficient is taken as 0.005. When the state of charge is in the high state of charge range, it reflects that the charge density on the electrode surface is close to saturation, the polarization effect is sharply enhanced, and the current influence coefficient is taken as 0.01. Next, the adjusted current influence coefficient 'a' is fed back to the polarization intensity calculation submodule to update the calculation of the polarization capacitance at the next time step. Based on the polarization capacitance at the next time step, the current sampling strategy at the next time step is dynamically adjusted. The specific current sampling strategy is as follows: If the polarization capacitance at the next moment is greater than the initial polarization capacitance × 1.2 (strong polarization), it indicates that the polarization loss is too large, and the charging and discharging current needs to be reduced (e.g., from 10A to 5A) to avoid overheating and capacity decay. If the polarization capacitance at the next moment is less than the initial polarization capacitance × 0.8 (weak polarization), it indicates that the polarization loss is small, and the charging and discharging current needs to be increased (e.g., from 5A to 10A) to improve the charging and discharging efficiency. If the initial polarization capacitance × 0.8 ≤ the polarization capacitance at the next moment ≤ the initial polarization capacitance × 1.2 (medium polarization), then the current charging and discharging current is maintained to balance efficiency and loss.

[0042] In the above embodiments, the adaptive control module realizes the adaptive adjustment of charging and discharging current through a closed-loop feedback mechanism of "state estimation → coefficient adjustment → strategy decision"; the current influence coefficient α is dynamically adjusted according to the SOC partition, reflecting the difference in polarization sensitivity in different SOC intervals; the current sampling strategy, based on the predicted polarization state, realizes the forward-looking adjustment of the current magnitude, achieving a dynamic balance between efficiency and loss.

[0043] The current influence coefficient 'a' is set according to the SOC range as follows: SOC (t+1) <30% (lower range): a=0.001; 30%≤SOC (t+1) ≤80% (middle interval): a=0.005; SOC (t+1) >80% (high interval) a=0.01.

[0044] This setting depends on different SOCs (t+1) The physical relationship between the surface charge density and polarization intensity of the lower electrode was obtained through experimental calibration and optimization. The current adjustment unit achieves smooth current regulation through a PWM controller, and the response time should be less than the control period Δt.

[0045] In summary, the adaptive control module of this embodiment utilizes SOC (t+1) Feedback and polarization state prediction enable intelligent dynamic control of charging and discharging current, which not only improves energy transmission efficiency but also effectively suppresses polarization loss and heat accumulation, extending the service life of the capacitor.

[0046] Example 6: Based on Example 5, the security protection module provided in this embodiment of the invention includes: The overcurrent protection unit triggers a relay to cut off the circuit when the current collected by the current sensing unit exceeds 1.5 times the rated current. The over-temperature protection unit activates the cooling fan and reduces the charging and discharging current when the core temperature collected by the temperature sensing unit exceeds 60°C. The overvoltage protection unit stops charging and starts the discharge circuit when the voltage collected by the voltage sensing unit exceeds 1.1 times the rated voltage.

[0047] In the above embodiments, the safety protection module serves as the hardware protection layer of the system, providing multiple protections against abnormal states; overcurrent protection prevents device damage caused by short circuits or overloads; overtemperature protection prevents thermal runaway through forced air cooling and load reduction operation; overvoltage protection avoids the risk of breakdown caused by charging voltage exceeding limits; each protection unit works independently and responds quickly, forming a "hardware-software combined" safety system with the software control layer.

[0048] The overcurrent protection threshold is set at 1.5 times the rated current to balance fault identification and malfunction prevention; the overtemperature protection threshold is set at 60℃ based on the thermal tolerance characteristics of the capacitor material; the overvoltage protection threshold is set at 1.1 times the rated voltage to account for a certain voltage fluctuation margin; the protection action actuators (such as relays, contactors, and cooling fans) must meet the requirements for response speed and load capacity, and industrial-grade components are usually selected.

[0049] In summary, the safety protection module of this embodiment provides a reliable safety barrier for the capacitor energy storage system through multiple hardware protection mechanisms, ensuring that the system can still operate safely under extreme or fault conditions, thereby improving the robustness and availability of the overall system.

[0050] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A capacitor energy storage system adaptive charge and discharge control system, characterized by, Comprise: State-aware module configured to collect capacitor state acquisition data including charging and discharging current, core temperature and terminal voltage data in real time through current sensor, temperature sensor and voltage sensor; Dynamic calculation module configured to integrate the state acquisition data collected by the state-aware module, and calculate the polarization capacitance, equivalent series resistance and state of charge of the capacitor through dynamic quantification algorithm; Adaptive control module configured to adjust the size and direction of the charging and discharging current through closed-loop feedback algorithm according to the polarization capacitance, equivalent series resistance and state of charge output by the dynamic calculation module; Safety protection module configured to trigger the hardware protection mechanism to cut off the charging and discharging circuit based on the overcurrent, overtemperature and overvoltage data collected by the state-aware module; The dynamic calculation module of the capacitor energy storage system adaptive charging and discharging control system comprises: Polarization intensity calculation submodule configured to combine real-time current and temperature data, and calculate the polarization state of the capacitor through coupling calculation of current relative intensity and temperature deviation, and output the polarization capacitance; Equivalent resistance calculation submodule configured to calculate the internal resistance loss of the capacitor based on the polarization capacitance and temperature deviation, and output the equivalent series resistance through nonlinear fitting of polarization relative value and temperature interval; State of charge update submodule configured to integrate ideal charging and discharging capacity and internal resistance loss, and predict the remaining state of charge of the capacitor at the next time through dynamic compensation algorithm.

2. The adaptive charge-discharge control system for a capacitor energy storage system of claim 1, wherein, The calculation logic of the polarization intensity calculation submodule is: The real-time charging and discharging current is collected by the current sensor, the first ratio of the charging and discharging current to the rated current is calculated, and the current correction term of the current on the polarization impact strength is affected by the product of the experimentally calibrated current influence coefficient; The real-time capacitor temperature is collected by the temperature sensor, the temperature deviation of the capacitor temperature from the preset reference temperature is calculated, and the first temperature correction term of the temperature on the polarization dissipation capacity is affected by the product of the experimentally calibrated first temperature influence coefficient; The current correction term and the first temperature correction term are weighted and coupled, and multiplied by the initial polarization capacitance to output the real-time polarization capacitance.

3. The adaptive charge-discharge control system for a capacitor energy storage system of claim 2, wherein, The calculation logic of the equivalent resistance calculation submodule is: Based on the polarization capacitance output by the polarization intensity calculation submodule, the second ratio of the polarization capacitance to the initial polarization capacitance is calculated, and the polarization correction term of the polarization on the internal resistance blocking effect is affected by the product of the experimentally calibrated polarization capacitance influence coefficient; Based on the temperature deviation calculated by the polarization intensity calculation submodule, the second temperature correction term of the temperature on the ohmic loss is calculated under the influence of the product of the experimentally calibrated second temperature influence coefficient; The fitting results of the polarization correction term and the second temperature correction term are coupled, and multiplied by the reference equivalent series resistance to output the real-time equivalent series resistance.

4. The adaptive charge-discharge control system for a capacitor energy storage system of claim 3, wherein, The calculation logic of the state of charge update submodule is: Based on the charging and discharging current collected by the current sensor, the proportion relationship of the charging and discharging current multiplied by the pre-set control period relative to the total capacitance is calculated, and the ideal charging and discharging capacity without loss is obtained; An internal resistance loss is obtained based on a product of the equivalent series resistance, the charging and discharging current and the control period, and the internal resistance loss is divided by a product of a rated voltage and a total capacitance to obtain an internal resistance loss energy; The state of charge at the previous time, the ideal charging and discharging amount and the internal resistance loss are dynamically coupled to output an updated state of charge at the next time.

5. The adaptive charge-discharge control system for a capacitor energy storage system of claim 4, wherein, The adaptive control module comprises: A current adjustment unit adjusts a duty cycle of the charging and discharging current through a PWM signal; A closed-loop feedback unit adjusts the current influence coefficient based on the state of charge output by the state of charge updating submodule and feeds back to the polarization intensity calculation submodule to update and calculate the polarization capacitance at the next time, and dynamically adjusts the current sampling strategy at the next time based on the polarization capacitance at the next time.

6. The adaptive charge-discharge control system of a capacitor energy storage system of claim 5, wherein, The adjustment of the current influence coefficient is based on the polarization characteristics of the state of charge interval preset in a specific manner as follows: When the state of charge is in a low state of charge interval, the electrode surface charge density is low and the polarization effect is weak, and the current influence coefficient is 0.001; When the state of charge is in a medium state of charge interval, the electrode surface charge density is moderate and the polarization effect is linearly enhanced with the state of charge, and the current influence coefficient is 0.005; When the state of charge is in a high state of charge interval, the electrode surface charge density is close to saturation and the polarization effect is sharply enhanced, and the current influence coefficient is 0.

01.

7. The adaptive charge-discharge control system for a capacitor energy storage system of claim 5, wherein, The current sampling strategy is specifically as follows: When the polarization capacitance at the next time > the initial polarization capacitance x 1.2, the polarization loss is too large, the charging and discharging current needs to be reduced to avoid overheating and capacity attenuation; When the polarization capacitance at the next time < the initial polarization capacitance x 0.8, the polarization loss is small, and the charging and discharging current needs to be increased to improve the charging and discharging efficiency; When the initial polarization capacitance x 0.8 ≤ the polarization capacitance at the next time ≤ the initial polarization capacitance x 1.2, the current charging and discharging current is maintained to balance the efficiency and loss.

8. The adaptive charge-discharge control system for a capacitor energy storage system of claim 1, wherein, The safety protection module comprises: An overcurrent protection unit triggers a relay to cut off the circuit when the current collected by the current sensing unit exceeds 1.5 times of the rated current; An overtemperature protection unit starts a cooling fan and reduces the charging and discharging current when the core temperature collected by the temperature sensing unit exceeds 60℃; An overvoltage protection unit stops charging and starts a discharging circuit when the voltage collected by the voltage sensing unit exceeds 1.1 times of the rated voltage.

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