Super capacitor and equalization method and device thereof

Abstract

The invention discloses a super capacitor and an equalization method and device thereof. The method comprises the following steps: acquiring an equalization starting voltage difference and an equalization current of a super capacitor monomer to be equalized; wherein the equalization starting voltage difference represents a voltage difference threshold value for controlling the super capacitor to start equalization; preset storage data are obtained, the preset storage data comprise the corresponding relation between different equalizing currents and different voltage recovery values, and the voltage recovery value matched with the equalizing current of the super capacitor single body is determined according to the preset storage data; determining an equalization ending voltage difference according to the equalization starting voltage difference and the voltage recovery value; wherein the equalization ending voltage difference represents a voltage difference threshold value for controlling the super capacitor to end equalization. According to the invention, the voltage difference after equalization is limited in a proper range, the repeated triggering of equalization is inhibited, and the stability of equalization is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of supercapacitors, and in particular to a supercapacitor and a balancing method and device thereof. BACKGROUND

[0002] As an electrochemical energy storage device, the relationship curve between time and voltage of a supercapacitor during constant current charging or discharging is usually more linear, and the supercapacitor is widely used in short-time high-power scenarios.

[0003] However, after the supercapacitor is charged and discharged, the voltage of the supercapacitor will recover due to charge redistribution. This phenomenon has a bad influence on the balancing of the supercapacitor, and how to improve the stability of the supercapacitor balancing has become a problem of concern in the industry. SUMMARY

[0004] In the prior art, balancing can maintain the voltage of each supercapacitor cell within a desired range, thereby ensuring that each supercapacitor cell remains in the same state during normal use to avoid overcharging and overdischarging. When the voltage difference between a supercapacitor cell and the supercapacitor cell with the lowest voltage reaches a certain threshold, the balancing is started. When the voltage difference between the supercapacitor cell and the supercapacitor cell with the lowest voltage recovers to below the threshold, the balancing is stopped. However, due to voltage recovery caused by charge redistribution, the voltage of the supercapacitor cell that has ended balancing will rise, causing the voltage difference between it and the supercapacitor cell with the lowest voltage to again meet the balancing start condition, and this cycle will continue, resulting in repeated starting and ending of balancing, and thus poor stability of the supercapacitor balancing. Therefore, the present application provides a supercapacitor and a balancing method and device thereof to inhibit repeated triggering of supercapacitor balancing and improve the stability of supercapacitor balancing.

[0005] According to an aspect of the present application, a balancing method of a supercapacitor is provided, comprising:

[0006] obtaining a balancing start voltage difference and a balancing current of a supercapacitor cell to be balanced, wherein the balancing start voltage difference represents a voltage difference threshold for starting balancing of the supercapacitor;

[0007] obtaining preset storage data containing a corresponding relationship between different balancing currents and different voltage recovery values, and determining a voltage recovery value matched with the balancing current of the supercapacitor cell according to the preset storage data;

[0008] determining a balancing end voltage difference according to the balancing start voltage difference and the voltage recovery value, wherein the balancing end voltage difference represents a voltage difference threshold for ending balancing of the supercapacitor.

[0009] Optionally, the method for obtaining the equalization current of the supercapacitor cell to be equalized specifically includes:

[0010] The voltage of each individual supercapacitor cell in the supercapacitor is collected, and the supercapacitor cell to be balanced is determined based on the equalization start-up voltage difference.

[0011] The equalization current is determined based on the voltage of the supercapacitor cell to be equalized and the equalization resistor in the equalization circuit.

[0012] Optionally, the number of supercapacitor cells to be equalized is at least two, and each supercapacitor cell to be equalized uses the same equalization termination voltage difference;

[0013] Before acquiring preset stored data characterizing the correspondence between equalization current and voltage recovery values, and matching the equalization current to the voltage recovery value of the supercapacitor cell to be equalized based on the preset stored data, the method further includes:

[0014] The voltage recovery value and the voltage difference at the end of the equalization process are determined by selecting the equalization current corresponding to the supercapacitor cell with the highest individual voltage.

[0015] Optionally, the number of supercapacitor cells to be balanced is at least two; if each supercapacitor cell to be balanced uses a different balancing circuit, then each supercapacitor cell to be balanced uses its own suitable balancing termination voltage difference.

[0016] Optionally, the method for obtaining the preset stored data characterizing the correspondence between the equalization current and the voltage recovery value specifically includes:

[0017] The supercapacitor cells were discharged using different equalizing currents.

[0018] A voltage metering device is used to collect the voltage values ​​of the supercapacitor at a first time and a second time; wherein, the first time is before the end of the discharge of the supercapacitor, and the second time is after the end of the discharge of the supercapacitor;

[0019] The voltage value at the second moment is subtracted from the voltage value at the first moment to obtain the voltage recovery value under the current equilibrium current.

[0020] Optionally, before discharging the supercapacitor cells with different equalizing currents, the method further includes:

[0021] Determine the initial voltage value of the supercapacitor cell before discharge;

[0022] After subtracting the voltage value at the second moment from the voltage value at the first moment to obtain the voltage recovery value under the current equalization current, the method further includes:

[0023] Change the initial voltage value of the supercapacitor cell before discharge, and repeat the steps of discharging the supercapacitor cell with different equalizing currents.

[0024] Optionally, the preset stored data further includes: the correspondence between different initial voltage values ​​and different voltage recovery values;

[0025] The voltage recovery value of the supercapacitor cell to be equalized is determined by the initial voltage value and the equalization current.

[0026] Optionally, the method for determining the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value specifically includes:

[0027] The difference between the equalization start-up voltage difference and the voltage recovery value is used to obtain the equalization end voltage difference threshold value.

[0028] The equilibrium termination pressure difference is set to be less than or equal to the equilibrium termination pressure difference threshold value.

[0029] Optionally, the difference between the equilibrium termination pressure difference and the equilibrium termination pressure difference threshold value is within a preset range.

[0030] Optionally, the equalization method for the supercapacitor further includes: enabling equalization;

[0031] The timing for initiating load balancing is as follows:

[0032] After determining the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value;

[0033] Alternatively, after determining the supercapacitor to be balanced, and before acquiring preset stored data characterizing the correspondence between the balancing current and the voltage recovery value, and matching the balancing current to the voltage recovery value of the supercapacitor to be balanced based on the preset stored data.

[0034] According to another aspect of the present invention, an equalization device for a supercapacitor is provided, comprising:

[0035] The equalization current acquisition module is used to acquire the equalization current of the equalization start-up voltage difference and the supercapacitor cell to be equalized.

[0036] The voltage recovery value acquisition module is used to acquire preset stored data, which includes the correspondence between different equalization currents and different voltage recovery values. Based on the preset stored data, the voltage recovery value matched by the equalization current of the supercapacitor cell is determined.

[0037] The equalization termination voltage difference determination module is used to determine the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value; wherein, the equalization start voltage difference represents the voltage difference threshold for controlling the supercapacitor to start equalization, and the equalization termination voltage difference represents the voltage difference threshold for controlling the supercapacitor to end equalization.

[0038] According to another aspect of the present invention, a supercapacitor is provided, comprising a plurality of supercapacitor cells, an equalization circuit, and a control module, wherein the control module executes the equalization method of the supercapacitor as described in any embodiment of the present invention.

[0039] The technical solution of this invention, by utilizing the correspondence between the voltage recovery value and the balancing current of a single supercapacitor cell, can obtain a more accurate balancing termination voltage difference. Specifically, the balancing current of the supercapacitor cell to be balanced is obtained, the voltage recovery value matching the balancing current of the supercapacitor cell is determined based on the preset stored data, and the balancing termination voltage difference is determined based on the balancing start voltage difference and the voltage recovery value. This achieves the comprehensive consideration of the balancing start voltage difference and the voltage recovery value to determine the balancing termination voltage difference. This setting provides a theoretical basis for determining the balancing termination voltage difference, which helps to limit the balancing termination voltage difference to a suitable range, both suppressing repeated balancing triggering and improving the over-balancing problem. Therefore, the supercapacitor balancing method provided by this invention can improve the stability of balancing.

[0040] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 A flowchart illustrating a supercapacitor equalization method provided in an embodiment of this specification;

[0043] Figure 2 A schematic flowchart illustrating another equalization method for supercapacitors provided in the embodiments of this specification;

[0044] Figure 3 A circuit diagram illustrating the discharge of a supercapacitor through an equalizing resistor, provided as an embodiment of this specification;

[0045] Figure 4 A flowchart illustrating another equalization method for supercapacitors provided in the embodiments of this specification;

[0046] Figure 5 A flowchart illustrating a method for acquiring preset stored data provided in an embodiment of this specification;

[0047] Figure 6 A flowchart illustrating another method for acquiring preset stored data provided in the embodiments of this specification;

[0048] Figure 7 A flowchart illustrating another equalization method for supercapacitors provided in the embodiments of this specification;

[0049] Figure 8 This is a schematic diagram of the structure of a supercapacitor equalization device provided in the embodiments of this specification. Detailed Implementation

[0050] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0052] This specification provides an embodiment of a supercapacitor equalization method. Figure 1 This is a schematic flowchart illustrating a supercapacitor balancing method provided in an embodiment of this specification. See also... Figure 1 The balancing method includes the following steps:

[0053] S110. Obtain the equalization start-up voltage difference and the equalization current of the supercapacitor cell to be equalized; wherein, the equalization start-up voltage difference characterizes the voltage difference threshold for controlling the start-up equalization of the supercapacitor.

[0054] Specifically, a supercapacitor comprises multiple individual supercapacitor cells. Due to aging and other factors, the voltage of each supercapacitor cell can change, resulting in voltage differences between different cells within the same supercapacitor. When these voltage differences are significant, the cells may overcharge or over-discharge, further degrading the supercapacitor's performance and lifespan. This problem can be effectively mitigated by employing a balancing method. The balancing activation condition is that, compared to the supercapacitor cell with the lowest voltage, a voltage difference between the current supercapacitor cell's voltage and the lowest voltage must reach the balancing activation voltage difference. This balancing activation voltage difference can be set according to actual needs, such as user-defined settings.

[0055] Equalization methods are generally divided into passive and active equalization. Regardless of the method used, the supercapacitor cells to be equalized need to be discharged during the equalization process, and the resulting discharge current is the equalization current. In some embodiments, passive equalization lowers the voltage of the supercapacitor cells to be equalized by discharging them, thus achieving equalization. In some embodiments, active equalization simultaneously discharges the supercapacitor cells to be equalized and uses the resulting energy to charge the supercapacitor cell with the lowest voltage, achieving equalization.

[0056] S120. Obtain preset stored data. The preset stored data contains the correspondence between different equalization currents and different voltage recovery values. Determine the voltage recovery value matching the equalization current of the supercapacitor cell based on the preset stored data.

[0057] The inventors discovered that the magnitude of the equalization current plays a decisive role in the voltage recovery of a single supercapacitor cell after discharge. For the same type of supercapacitor cell, the voltage recovery value corresponding to different equalization currents can be determined in advance through experiments, thereby obtaining preset storage data.

[0058] S130. Determine the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value; wherein, the equalization termination voltage difference characterizes the voltage difference threshold at which the supercapacitor ends equalization.

[0059] As the foregoing analysis shows, balancing can reduce the voltage of the supercapacitor cell to be balanced, or simultaneously reduce the voltage of the cell to be balanced and increase the voltage of the cell with the lowest voltage. As the voltage of the supercapacitor cell to be balanced decreases, the voltage difference between it and the cell with the lowest voltage gradually narrows until the balancing process ends. It should be noted that once the supercapacitor cell to be balanced begins balancing, it is more appropriate to refer to it as a balanced supercapacitor cell. For consistency, the term "supercapacitor cell to be balanced" will be used in subsequent descriptions.

[0060] Setting a reasonable equalization termination voltage differential is beneficial to improving equalization stability. If the equalization termination voltage differential is set too large, meaning that equalization ends while the voltage difference between the supercapacitor cell to be equalized and the supercapacitor cell with the lowest voltage is still relatively large, this setting helps reduce the energy consumption caused by equalization. However, after the supercapacitor cell to be equalized ends equalization, there is a phenomenon of voltage self-recovery, meaning that the voltage of the supercapacitor cell to be equalized will rise. The voltage difference between the cell with the risen voltage and the supercapacitor cell with the lowest voltage may again reach the equalization start voltage differential, thus causing equalization to be repeatedly triggered.

[0061] If the equalization termination voltage difference is set too small, that is, the equalization ends when the voltage difference between the supercapacitor cell to be equalized and the supercapacitor cell with the lowest voltage is very small, this setting can effectively avoid the equalization being repeatedly triggered, but it is easy to cause over-equalization.

[0062] The embodiments in this specification determine the equalization termination voltage difference by comprehensively considering the equalization start-up voltage difference and the voltage recovery value, providing a theoretical basis for determining the equalization termination voltage difference. This helps to limit the equalization termination voltage difference to a suitable range, which is beneficial for suppressing repeated equalization triggering and improving the problem of over-equalization. Therefore, the equalization method of supercapacitors provided in the embodiments of this specification can improve the stability of equalization.

[0063] Based on the above embodiments, optionally, the method for determining the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value specifically includes:

[0064] Balance the opening pressure difference ΔU1 and the voltage recovery value ΔU rec By subtracting the values, we obtain the equilibrium termination pressure threshold value ΔU. th ; expressed by the formula ΔU th =ΔU1-ΔU rec ;

[0065] Set the equilibrium termination pressure difference ΔU2 to be less than or equal to the equilibrium termination pressure difference threshold value ΔU th Furthermore, the difference between the equilibrium termination pressure differential and the equilibrium termination pressure differential threshold value is within the preset range ΔU. ran Internal; expressed by the formula ΔU2=ΔU1-ΔU rec -ΔU ran Among them, the preset range ΔU ran This represents the equilibrium termination pressure difference ΔU2 and the equilibrium termination pressure difference threshold ΔU. th The fluctuation range between them, the preset range ΔU ranIt can be configured as needed, for example, according to user requirements. In special cases, the equilibrium termination pressure differential ΔU2 can be set to equal the equilibrium termination pressure differential threshold value ΔU. th That is, ΔU2 = ΔU th =ΔU1-ΔU rec .

[0066] The embodiments in this specification are configured in such a way that it helps to limit the equalization termination pressure difference within a suitable range, which is beneficial for both suppressing repeated equalization triggering and improving the problem of over-equalization. Specifically, if the set equalization termination pressure difference ΔU2' is greater than the aforementioned ΔU2, that is, if the set equalization termination pressure difference is large, then if the preset range ΔU is not considered... ran From ΔU2=ΔU1-ΔU rec It can be seen that the voltage of the supercapacitor elevator after balancing is ΔU2' + ΔU rec If the equilibrium opening pressure difference is greater than ΔU1, it is easy to cause repeated equilibrium triggering. If the equilibrium ending pressure difference ΔU2' is less than the above ΔU2, it is easy to waste energy or even cause over-equilibrium.

[0067] It should be noted that the above embodiments exemplify the method of determining the balancing termination voltage difference based on the balancing start voltage difference and voltage recovery value through calculation, and are not intended to limit the scope of this specification. In other embodiments, a lookup table method can also be used. Specifically, the balancing start voltage difference, voltage recovery value, and their corresponding balancing termination voltage difference are stored in a table, and the balancing termination voltage difference is determined by using the balancing start voltage difference and voltage recovery value as indexes and the balancing termination voltage difference as the lookup result.

[0068] In the above embodiments, there are various methods for obtaining the equalization current depending on the equalization circuit. These methods will be described in detail below, but they are not intended to limit this specification.

[0069] Figure 2 This is a schematic flowchart illustrating another supercapacitor balancing method provided in the embodiments of this specification. See also... Figure 2 In one embodiment, optionally, S110, the method for obtaining the equalization current of the supercapacitor cell to be equalized specifically includes:

[0070] S111. Collect the voltage of each supercapacitor cell in the supercapacitor, and determine the supercapacitor cell to be balanced based on the equalization start-up voltage difference.

[0071] As supercapacitors are used, the voltages of individual supercapacitor cells gradually differ, with some cells having higher voltages and others lower voltages. When a supercapacitor cell's voltage reaches a certain level, it needs to be discharged to equalize the voltages of all cells. Typically, the supercapacitor cell with the lowest voltage is used as a benchmark. The voltage difference between the other supercapacitor cells and the lowest voltage cell is calculated. If the voltage difference exceeds the equalization threshold voltage, the supercapacitor cell with the higher voltage is the one that needs to be equalized.

[0072] S112. Determine the balancing current based on the voltage of the supercapacitor cell to be balanced and the balancing resistor in the balancing circuit.

[0073] One method for equalizing the individual supercapacitor cells is to discharge them, which generates a discharge current. In one implementation, such as... Figure 3 As shown, the equalization circuit only includes equalization resistors. Figure 3 The diagram illustrates an equalization circuit comprising equalization resistors R1, R2, R3, and R4. Equalization resistor R1 is used to equalize supercapacitor C1, R2 to equalize supercapacitor C2, R3 to equalize supercapacitor C3, and R4 to equalize supercapacitor C4. The supercapacitor cells to be equalized discharge through the equalization resistors. Using Ohm's law, the equalization current can be determined based on the voltage of the supercapacitor cell and the equalization resistor. In another embodiment, the devices in the discharge path of the equalization circuit can determine an equivalent equalization resistance. Using Ohm's law, the equalization current can be determined based on the voltage of the supercapacitor cell and the equivalent equalization resistance.

[0074] The equalization current can be determined through S111-S112, and the implementation method is simple and easy to implement.

[0075] In the above embodiments, the number of supercapacitor cells to be balanced, as confirmed by the equalization of the opening voltage difference, may be one or at least two.

[0076] In one implementation, when there is only one supercapacitor cell to be equalized, it is only necessary to equalize that supercapacitor cell.

[0077] In another implementation, when there are at least two supercapacitor cells to be balanced, if each supercapacitor cell uses a different balancing circuit, the different balancing circuits can be triggered individually. In this case, each supercapacitor cell can use its own suitable balancing termination voltage difference. For example, there are two supercapacitor cells to be balanced, namely supercapacitor cell 1 and supercapacitor cell 2. The balancing current corresponding to supercapacitor cell 1 is I1, the voltage recovery value is ΔU1, and the balancing start voltage difference is ΔU. 11 The pressure difference at the end of equilibrium is ΔU 12 The equalization current for supercapacitor cell 2 is I2, the voltage recovery value is ΔU2, and the equalization turn-on voltage difference is ΔU. 21 The pressure difference at the end of equilibrium is ΔU 22 Therefore, the equilibrium termination pressure difference ΔU is adopted. 12 The determination of the end of equalization for supercapacitor cell 1 is based on the equalization end voltage difference ΔU. 22 The equalization process for supercapacitor cell 2 is determined. This setting allows for more precise control over the equalization process.

[0078] In another implementation, optionally, when the number of supercapacitor cells to be equalized is at least two, each supercapacitor cell to be equalized uses the same equalization termination voltage difference. Specifically, Figure 4 This is a schematic flowchart illustrating another supercapacitor balancing method provided in the embodiments of this specification. See also... Figure 4 The balancing method includes the following steps:

[0079] S210, Obtain the equalization turn-on voltage difference and the equalization current of at least two supercapacitor cells to be equalized.

[0080] S220. Select the supercapacitor cell with the highest voltage from at least two supercapacitor cells to be balanced; wherein the supercapacitor cell with the highest voltage corresponds to the maximum balancing current.

[0081] Among them, the supercapacitor with the highest single-cell voltage also corresponds to the largest balancing current. The maximum balancing current is... max This indicates that, generally speaking, the larger the balancing current, the greater the corresponding voltage recovery value. Therefore, the maximum balancing current Im... ax Corresponding maximum voltage recovery value ΔU max In subsequent steps, the maximum balancing current I is used. max Determine the maximum voltage recovery value ΔU max And the pressure difference at the end of the equilibrium.

[0082] S230. Obtain preset stored data representing the correspondence between equalization current and voltage recovery value, and determine the maximum voltage recovery value matching the maximum equalization current based on the preset stored data.

[0083] S240. Determine the equalization termination pressure difference based on the equalization start pressure difference and the maximum voltage recovery value.

[0084] Wherein, the voltage difference at the start of the equalization process is represented by ΔU1, the voltage difference at the end of the equalization process is represented by ΔU2, and the maximum voltage recovery value is represented by ΔU. max This indicates that the equalization opening voltage difference ΔU1 and the maximum voltage recovery value ΔU are known. max This allows us to derive the equilibrium termination pressure difference ΔU2, ensuring that ΔU2 is limited to a suitable range. This approach helps suppress repeated equilibrium triggering and mitigates overequilibrium issues. For example, ΔU2 = ΔU1 - ΔU max From this formula, it can be seen that the equalization opening voltage difference ΔU1 is a fixed value, and the maximum voltage recovery value ΔU max The voltage difference ΔU2 at the end of equalization is the maximum value obtained among the individual supercapacitors to be equalized, and the voltage difference at the end of equalization is the minimum value obtained among the individual supercapacitors to be equalized. This setting ensures that the voltage recovery of the supercapacitor with the highest voltage after equalization does not cause repeated equalization triggers, thus ensuring that the voltage recovery of each supercapacitor to be equalized after equalization does not cause repeated equalization triggers.

[0085] Using S210-S240, each supercapacitor cell to be equalized can be given the same equalization termination voltage difference, making the setting process simple and easy to implement.

[0086] Based on the above embodiments, the preset stored data characterizing the correspondence between the equalization current and voltage recovery values ​​can be pre-stored before leaving the factory. There are various methods for obtaining this preset stored data, which will be specifically described below, but this is not intended to limit this specification.

[0087] Figure 5 This is a flowchart illustrating a method for acquiring preset stored data, provided in an embodiment of this specification. See also... Figure 5 In one embodiment of this specification, optionally, a preset method for obtaining stored data includes the following steps:

[0088] S310, different equalization currents are used to discharge the supercapacitor cells respectively.

[0089] Since the equalization current generated during equalization is usually different in practical applications, and the equalization current plays a major role in the voltage recovery value, it is necessary to test the voltage recovery value of each supercapacitor cell when using different equalization currents.

[0090] S320. A voltage metering device is used to collect the voltage values ​​of the supercapacitor at the first and second moments; wherein the first moment is before the end of the supercapacitor's discharge, and the second moment is after the end of the supercapacitor's discharge.

[0091] In supercapacitors, voltage recovery occurs after discharge, a phenomenon known as a sudden voltage increase. From the perspective of a voltage meter measuring on the order of seconds (s), this voltage recovery is instantaneous, representing a voltage surge. After recovery, the supercapacitor's voltage remains essentially constant. However, when this voltage surge is amplified over time, with a voltage meter measuring on the order of milliseconds (ms) or higher, the voltage recovery may appear gradual. In practical applications, the voltage meter monitors the supercapacitor in real time. The voltage value at the moment immediately before the end of discharge can be selected as the first time value, and the voltage value at the moment immediately after the end of discharge or at a predetermined time after the end of discharge can be selected as the second time value. The voltage meter can be a built-in device within the supercapacitor or an external device, such as a voltmeter.

[0092] S330. Subtract the voltage value at the second moment from the voltage value at the first moment to obtain the voltage recovery value under the current equalization current.

[0093] Specifically, the voltage recovery values ​​under each equalization current can be recorded and statistically analyzed to obtain preset storage data. This preset storage data can be stored in the form of tables or curves; it is two-dimensional data, with the equalization current dimension and the voltage recovery value dimension.

[0094] Preset storage data can be obtained through S310-S330, which is easy to implement.

[0095] Figure 6 This is a flowchart illustrating another method for acquiring preset stored data provided in an embodiment of this specification. See also... Figure 6 In another embodiment of this specification, optionally, a method for obtaining stored data is preset, specifically including the following steps:

[0096] S410. Determine the initial voltage value of a single supercapacitor cell before discharge.

[0097] The voltage recovery value of a single supercapacitor cell is mainly related to the discharge current. However, the initial voltage value of the supercapacitor cell before discharge also has a certain impact on the voltage recovery value. By determining the initial voltage value of the supercapacitor cell before discharge, the corresponding voltage recovery value can be made more accurate.

[0098] S420 uses different equalizing currents to discharge the supercapacitor cells.

[0099] S430: A voltage metering device is used to collect the voltage values ​​of the supercapacitor at the first and second moments.

[0100] The voltage metering device can be a built-in metering device in the supercapacitor or an external voltage metering device, such as a voltmeter.

[0101] S440. Subtract the voltage value at the second moment from the voltage value at the first moment to obtain the voltage recovery value under the current equilibrium current.

[0102] S450: Determine whether to continue changing the initial voltage value of the supercapacitor cell before discharge; if yes, execute S460 and then return to execute S410; otherwise, end.

[0103] S460, Change the initial voltage value of a single supercapacitor cell before discharge.

[0104] Specifically, by recording and statistically analyzing the voltage recovery values ​​under various equalization currents corresponding to the voltage values ​​before discharge, a preset storage data set containing the initial voltage values ​​before discharge and the correspondence between different initial voltage values ​​and different voltage recovery values ​​can be obtained. Therefore, the voltage recovery value of the supercapacitor cell to be equalized is determined by both the initial voltage value and the equalization current. This preset storage data can be stored in the form of tables or curves, and it is three-dimensional data, with the three dimensions being the initial voltage value, the equalization current dimension, and the voltage recovery value dimension.

[0105] S410-S460 can obtain preset stored data including the voltage value before discharge, making the determination of the voltage recovery value more accurate.

[0106] Using the above method, correspondingly, when executing the method of determining the voltage recovery value of the equalization current matching of the supercapacitor cell based on the preset stored data, it further includes: matching the voltage recovery value of the supercapacitor cell to be equalized to its pre-discharge voltage. Specifically, Figure 7 This is a schematic flowchart illustrating another supercapacitor balancing method provided in the embodiments of this specification. See also... Figure 7 Based on the above embodiments, the equalization method may optionally include the following steps:

[0107] S510: Obtain the equalization start-up voltage difference and the pre-discharge voltage and equalization current of the supercapacitor cell to be equalized.

[0108] S520: Obtain preset stored data characterizing the correspondence between the initial voltage, equalization current, and voltage recovery value before discharge; determine the voltage recovery value matching the equalization current of the supercapacitor cell to be equalized based on the preset stored data.

[0109] S530. Determine the equalization termination pressure difference based on the equalization start pressure difference and voltage recovery value.

[0110] Through S510-S530, the voltage recovery value can be obtained from preset stored data including the voltage value before discharge, so the determination of the voltage recovery value is more accurate, thereby making the determination of the equalization end voltage difference more accurate.

[0111] Based on the above embodiments, optionally, the supercapacitor balancing method further includes: activating balancing. That is, after determining the supercapacitor cell to be balanced, balancing is activated for the corresponding supercapacitor cell. This specification does not limit the timing of activating balancing; it can be activated before or after determining the balancing end voltage difference. Specifically, determining the balancing end voltage difference can be performed in the controller. The time consumed in determining the balancing end voltage difference is negligible compared to the duration of balancing the supercapacitor cell, and even if balancing is activated early, it will not affect the determination of the balancing end voltage difference. For example, the timing of activating balancing is: after determining the balancing end voltage difference based on the balancing activation voltage difference and the voltage recovery value; or, after determining the supercapacitor to be balanced, and before acquiring preset stored data characterizing the correspondence between the balancing current and the voltage recovery value, and determining the voltage recovery value matching the balancing current of the supercapacitor cell to be balanced based on the preset stored data.

[0112] It should be noted that the above embodiments exemplify methods for determining the equalization termination voltage difference only for supercapacitor cells with higher voltages, and are not intended to limit this specification. In other embodiments, if the equalization includes not only discharging equalization of supercapacitor cells with higher voltages but also charging equalization of supercapacitor cells with lower voltages, then it is also necessary to consider determining the equalization termination voltage difference for charging equalization of supercapacitor cells. The determination method is similar and will not be repeated here.

[0113] This specification also provides an equalization device for a supercapacitor, which can be configured in the controller of the supercapacitor and can be implemented by software and / or hardware. Figure 8 This is a schematic diagram of the structure of a supercapacitor equalization device provided in an embodiment of this specification. See also... Figure 8 The device includes:

[0114] The equalization current acquisition module 610 is used to acquire the equalization start-up voltage difference and the equalization current of the supercapacitor cell to be equalized.

[0115] The voltage recovery value acquisition module 620 is used to acquire preset stored data. The preset stored data contains the correspondence between different equalization currents and different voltage recovery values. Based on the preset stored data, the voltage recovery value matching the equalization current of the supercapacitor cell to be equalized is determined.

[0116] The equalization termination voltage difference determination module 630 is used to determine the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value; wherein, the equalization start voltage difference represents the voltage difference threshold for controlling the supercapacitor to start equalization, and the equalization termination voltage difference represents the voltage difference threshold for controlling the supercapacitor to end equalization.

[0117] Optionally, the equalization current acquisition module 610 specifically includes:

[0118] The individual cell voltage acquisition unit is used to acquire the voltage of each cell in the supercapacitor and determine the supercapacitor cell to be balanced based on the equalization start-up voltage difference.

[0119] The current determination unit is used to determine the equalization current based on the voltage of the supercapacitor cell to be equalized and the equalization resistor in the equalization circuit.

[0120] Optionally, the number of supercapacitor cells to be equalized is at least two, and each supercapacitor cell to be equalized uses the same equalization termination voltage difference;

[0121] The equalization current acquisition module 610 selects the supercapacitor cell with the highest individual voltage and determines the subsequent voltage recovery value and the voltage difference at the end of equalization.

[0122] Optionally, the number of supercapacitor cells to be balanced is at least two; if each supercapacitor cell to be balanced uses a different balancing circuit, then each supercapacitor cell to be balanced uses its own suitable balancing termination voltage difference.

[0123] Optionally, the device further includes a preset stored data acquisition module, used to acquire preset stored data characterizing the correspondence between the equalization current and voltage recovery values. The preset stored data acquisition module is specifically used for:

[0124] Different equalization currents were used to discharge the individual supercapacitor cells;

[0125] A voltage metering device was used to collect the voltage values ​​of the supercapacitor at the first and second moments; the first moment was before the supercapacitor finished discharging, and the second moment was after the supercapacitor finished discharging.

[0126] The voltage value at the second moment is subtracted from the voltage value at the first moment to obtain the voltage recovery value under the current equilibrium current.

[0127] Optionally, the preset data acquisition module is also used before discharging the supercapacitor cells using different equalizing currents:

[0128] Determine the pre-discharge voltage value of a single supercapacitor cell;

[0129] After subtracting the voltage value at the second moment from the voltage value at the first moment to obtain the voltage recovery value under the current equilibrium current, the process also includes:

[0130] By changing the pre-discharge voltage of a single supercapacitor cell, the steps of discharging the supercapacitor cell using different equalization currents are repeated.

[0131] Optionally, the voltage recovery value acquisition module 620 is also used to match the voltage recovery value of the supercapacitor cell to be equalized with its pre-discharge voltage.

[0132] Optionally, the equalization end pressure difference determination module 630 specifically includes:

[0133] The threshold value determination unit is used to subtract the equalization start voltage difference and the voltage recovery value to obtain the equalization end voltage difference threshold value.

[0134] The equilibrium termination pressure difference determination unit is used to set the equilibrium termination pressure difference to be less than or equal to the equilibrium termination pressure difference threshold value, and the difference between the equilibrium termination pressure difference and the equilibrium termination pressure difference threshold value is within a preset range.

[0135] Optionally, the device further includes: a balancing activation control unit for activating balancing;

[0136] In one embodiment, the timing for initiating load balancing is as follows:

[0137] After determining the equalization termination pressure difference based on the equalization start pressure difference and voltage recovery value.

[0138] This setting is equivalent to determining all the physical quantities (including the balancing current and the balancing end voltage difference) required for the balancing process before starting the balancing process. This makes the balancing process clear and facilitates timely termination of the balancing process when the balancing end voltage difference is reached, thus making the balancing process more stable.

[0139] Alternatively, in another embodiment, the timing for initiating equalization is: after determining the supercapacitor to be equalized, and before acquiring preset stored data characterizing the correspondence between equalization current and voltage recovery values, and determining the voltage recovery value matching the equalization current of the supercapacitor cell based on the preset stored data.

[0140] This configuration is equivalent to initiating balancing after the balancing current is determined but before the balancing end voltage difference is determined. Compared to the previous embodiment, this is equivalent to initiating balancing earlier, as the balancing current is already determined, making early balancing possible. Furthermore, this helps to shorten the overall balancing time for the supercapacitor, thereby improving balancing efficiency. During the balancing process, the steps for determining the balancing end voltage difference are performed simultaneously. Typically, the time consumed in determining the balancing end voltage difference is negligible compared to the duration of balancing individual supercapacitor cells; therefore, this embodiment of the invention can calculate the accurate balancing end voltage difference before it is reached.

[0141] The supercapacitor equalization device provided in the embodiments of this specification can execute the supercapacitor equalization method provided in any embodiment of this specification, and has the corresponding functional modules and beneficial effects of the method.

[0142] This specification also provides a supercapacitor, which includes multiple supercapacitor cells, an equalization circuit, and a control module. The control module executes the equalization method of the supercapacitor provided in any embodiment of this specification, and has corresponding beneficial effects.

[0143] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this specification can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution in this specification can be achieved, and this document does not impose any restrictions on this.

[0144] The specific embodiments described above do not constitute a limitation on the scope of protection of this specification. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this specification should be included within the scope of protection of this specification.

Claims

1. A method for equalizing a supercapacitor, characterized in that, include: The equalization start-up voltage difference and the equalization current of the supercapacitor cell to be equalized are obtained; wherein, the equalization start-up voltage difference represents the voltage difference threshold that controls the equalization start-up of the supercapacitor. Acquire preset stored data, which contains the correspondence between different equalization currents and different voltage recovery values, and determine the voltage recovery value matching the equalization current of the supercapacitor cell based on the preset stored data; The equalization termination voltage difference is determined based on the equalization start voltage difference and the voltage recovery value; wherein, the equalization termination voltage difference represents the voltage difference threshold that controls the supercapacitor to end equalization.

2. The equalization method for supercapacitors according to claim 1, characterized in that, The method for obtaining the equalization current of the supercapacitor cell to be equalized specifically includes: The voltage of each individual supercapacitor cell in the supercapacitor is collected, and the supercapacitor cell to be balanced is determined based on the equalization start-up voltage difference. The equalization current is determined based on the voltage of the supercapacitor cell to be equalized and the equalization resistor in the equalization circuit.

3. The equalization method for supercapacitors according to claim 1 or 2, characterized in that, The number of supercapacitor cells to be equalized is at least two, and each supercapacitor cell to be equalized uses the same equalization termination voltage difference. Before acquiring preset stored data, which includes the correspondence between different equalization currents and different voltage recovery values, and determining the voltage recovery value matching the equalization current of the supercapacitor cell based on the preset stored data, the process further includes: The voltage recovery value and the voltage difference at the end of the equalization process are determined by selecting the equalization current corresponding to the supercapacitor cell with the highest individual voltage.

4. The equalization method for supercapacitors according to claim 1 or 2, characterized in that, The number of supercapacitor cells to be balanced is at least two; if each supercapacitor cell to be balanced uses a different balancing circuit, then each supercapacitor cell to be balanced uses its own suitable balancing termination voltage difference.

5. The equalization method for supercapacitors according to claim 1, characterized in that, The method for obtaining the preset stored data specifically includes: The supercapacitor cells were discharged using different equalizing currents. A voltage metering device is used to collect the voltage values ​​of the supercapacitor at a first time and a second time; wherein, the first time is before the end of the discharge of the supercapacitor, and the second time is after the end of the discharge of the supercapacitor. The voltage value at the second moment is subtracted from the voltage value at the first moment to obtain the voltage recovery value under the current equilibrium current.

6. The equalization method for supercapacitors according to claim 5, characterized in that, Before discharging the supercapacitor cells using different equalizing currents, the method further includes: Determine the initial voltage value of the supercapacitor cell before discharge; After subtracting the voltage value at the second moment from the voltage value at the first moment to obtain the voltage recovery value under the current equalization current, the method further includes: Change the initial voltage value of the supercapacitor cell before discharge, and repeat the steps of discharging the supercapacitor cell with different equalizing currents.

7. The equalization method for supercapacitors according to claim 6, characterized in that, The preset stored data also includes: the correspondence between different initial voltage values ​​and different voltage recovery values; The voltage recovery value of the supercapacitor cell to be equalized is determined by the initial voltage value and the equalization current.

8. The equalization method for supercapacitors according to claim 1, characterized in that, The method for determining the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value specifically includes: The difference between the equalization start-up voltage difference and the voltage recovery value is used to obtain the equalization end voltage difference threshold value. The equilibrium termination pressure difference is set to be less than or equal to the equilibrium termination pressure difference threshold value.

9. The equalization method for supercapacitors according to claim 8, characterized in that, The difference between the equilibrium termination pressure difference and the equilibrium termination pressure difference threshold value is within a preset range.

10. The equalization method for supercapacitors according to claim 1, characterized in that, Also includes: Enable balance; The timing for initiating load balancing is as follows: After determining the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value; Alternatively, after determining the supercapacitor to be balanced, and before acquiring preset stored data, which contains the correspondence between different balancing currents and different voltage recovery values, and determining the voltage recovery value matching the balancing current of the supercapacitor cell based on the preset stored data.

11. An equalization device for a supercapacitor, characterized in that, include: The equalization current acquisition module is used to acquire the equalization current of the equalization start-up voltage difference and the supercapacitor cell to be equalized. The voltage recovery value acquisition module is used to acquire preset stored data, which includes the correspondence between different equalization currents and different voltage recovery values. Based on the preset stored data, the voltage recovery value matched by the equalization current of the supercapacitor cell is determined. The equalization termination voltage difference determination module is used to determine the equalization termination voltage difference based on the equalization start voltage difference and the voltage recovery value; wherein, the equalization start voltage difference represents the voltage difference threshold for controlling the supercapacitor to start equalization, and the equalization termination voltage difference represents the voltage difference threshold for controlling the supercapacitor to end equalization.

12. A supercapacitor, characterized in that, It includes multiple supercapacitor cells, an equalization circuit, and a control module, wherein the control module performs the equalization method for the supercapacitors as described in any one of claims 1-10.

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