Energy storage device voltage equalization control method and device

Abstract

The application relates to a kind of energy storage device voltage equalization control method and device, the voltage instantaneous value of each group of energy storage device is monitored in real time;The voltage instantaneous value of each group of energy storage device is sorted, and the power adjustment coefficient of each group of energy storage device is configured according to the sorting result;According to the power adjustment coefficient, the adjustment amount of the control amount directly related to power is configured;The maximum value of the voltage instantaneous value difference of each group of energy storage device is calculated, and if it is greater than the set threshold, the power is adjusted according to the adjustment amount, otherwise the controller does not adjust the power.The energy storage device voltage equalization control method and device of the application can ensure that the voltage of each group of energy storage device is balanced.The adjustment amount is calculated in real time, but only when the maximum value of the voltage instantaneous value difference of each group of energy storage device exceeds the threshold, adjustment is carried out, to avoid frequent adjustment.

Description

Technical Field

[0001] This invention relates to the field of voltage equalization control technology, and in particular to a voltage equalization control method and apparatus for energy storage devices. Background Technology

[0002] The energy storage device is connected to the DC distribution network via a DC / DC converter. The high-voltage side of the DC / DC converter is connected in series and directly connected to the DC bus of the DC distribution network. The low-voltage side is connected in parallel in groups, with each group connected to a separate energy storage device. Due to limitations in technology, there are differences between the groups of energy storage devices and between the DC / DC converters connected to the energy storage devices, resulting in voltage imbalances during the charging and discharging process of the energy storage devices.

[0003] Current technology connects one energy storage device to the low-voltage side of each high-frequency isolation transformer, but has not yet studied the voltage imbalance problem when multiple energy storage devices are connected.

[0004] When multiple energy storage devices are connected in parallel on the low-voltage side of a high-frequency isolation DC transformer, the voltage of each energy storage device becomes unbalanced due to differences in the parameters of the primary equipment. There is currently no solution to this problem. Summary of the Invention

[0005] To address the problem of voltage imbalance in energy storage devices caused by inconsistent primary equipment parameters, this invention provides a voltage balancing control method and apparatus for energy storage devices, ensuring voltage balance among different groups of energy storage devices.

[0006] To achieve the above objectives, the present invention provides a voltage equalization control method for an energy storage device, comprising:

[0007] Real-time monitoring of the instantaneous voltage values ​​of each group of energy storage devices;

[0008] The instantaneous voltage values ​​of each group of energy storage devices are sorted, and the power adjustment coefficient of each group of energy storage devices is configured according to the sorting results.

[0009] Based on the power adjustment coefficient, configure the adjustment amount of the control quantity directly related to the power;

[0010] Calculate the maximum value of the instantaneous voltage difference between each group of energy storage devices. If it is greater than the set threshold, adjust the power according to the adjustment amount; otherwise, the controller does not adjust the power.

[0011] Furthermore, the instantaneous voltage values ​​of each group of energy storage devices are sorted, and the power adjustment coefficients of each group of energy storage devices are configured according to the sorting results, including: according to the voltage u i Sort by size from largest to smallest, power adjustment coefficient p i for:

[0012]

[0013] Where i is the sorting number and k is a constant value for the power adjustment coefficient.

[0014] Furthermore, based on the power adjustment coefficient, the adjustment amount of the control quantity directly related to the power is configured, including:

[0015] If it is a low-voltage side control mode, the adjustment amount of the control quantity is:

[0016]

[0017] Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refi u is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0018] If it is a high-voltage side control mode, the adjustment amount of the control quantity is:

[0019]

[0020] Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

[0021] Further, adjusting the power according to the stated adjustment amount includes:

[0022] If it is in low-voltage side control mode, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This is superimposed on the low-voltage side current command value;

[0023] If it is in high-voltage side control mode, dHu hi The command value superimposed on the high-voltage side equalization controller will be dHu li It is superimposed on the low-voltage side capacitor voltage command value.

[0024] Another aspect of the present invention provides a voltage equalization control device for an energy storage device, comprising:

[0025] The acquisition module acquires the instantaneous voltage values ​​of each group of energy storage devices in real time;

[0026] The adjustment coefficient determination module sorts the instantaneous voltage values ​​of each group of energy storage devices and configures the power adjustment coefficient of each group of energy storage devices according to the sorting results.

[0027] The adjustment amount determination module configures the adjustment amount of the control quantity directly related to the power based on the power adjustment coefficient;

[0028] The control module is adjusted to calculate the maximum value of the instantaneous voltage difference between each group of energy storage devices. If the difference is greater than the set threshold, the power is adjusted according to the adjustment amount determined by the adjustment amount determination module; otherwise, the controller does not adjust the power.

[0029] Furthermore, the adjustment coefficient determination module, according to the voltage u i Sort the data from largest to smallest, and calculate the power adjustment coefficient p. i for:

[0030]

[0031] Where i is the sorting number and k is a constant value for the power adjustment coefficient.

[0032] Furthermore, the adjustment amount determination module configures the adjustment amount of the control quantity directly related to the power, including:

[0033] If it is a low-voltage side control mode, the adjustment amount of the control quantity is:

[0034]

[0035] Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refi u is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0036] If it is a high-voltage side control mode, the adjustment amount of the control quantity is:

[0037]

[0038] Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

[0039] Further, adjusting the power by adjusting the amount mentioned in the control module includes:

[0040] If it is in low-voltage side control mode, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This is superimposed on the low-voltage side current command value;

[0041] If it is in high-voltage side control mode, dHu hi The command value superimposed on the high-voltage side equalization controller will be dHu li It is superimposed on the low-voltage side capacitor voltage command value.

[0042] The above-described technical solution of the present invention has the following beneficial technical effects:

[0043] (1) The voltage equalization control method and device for energy storage devices of the present invention can ensure the voltage equalization of each group of energy storage devices.

[0044] (2) The energy storage device voltage equalization control method and device of the present invention calculates the adjustment amount in real time, but only makes adjustments when the maximum value of the difference between the instantaneous voltage values ​​of each group of energy storage devices exceeds the threshold, thus avoiding frequent adjustments.

[0045] (3) The present invention provides power adjustment methods for high-voltage side control mode and low-voltage side control mode respectively, ensuring the universality of equalization control. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the high-voltage side and low-voltage side of the energy storage device;

[0047] Figure 2 Flowchart of voltage equalization control method for energy storage devices;

[0048] Figure 3 This is a schematic diagram of the low-voltage side control device;

[0049] Figure 4 This is a schematic diagram of the high-voltage side control device;

[0050] Figure 5 This is a schematic diagram of the low-voltage side control mode;

[0051] Figure 6 This is a schematic diagram of the high-voltage side control mode;

[0052] Figure 7 This is a schematic diagram of the low-voltage side control adjustment;

[0053] Figure 8 This is a schematic diagram of the high-voltage side control adjustment. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0055] This invention provides a voltage equalization control method for energy storage devices, wherein the controlled objects are DC / DC converters connected in series on the high-voltage side and in parallel groups on the low-voltage side, and the connected energy storage devices, such as... Figure 1 As shown.

[0056] Voltage balancing control method for energy storage devices, combined with Figure 2 Its implementation includes the following steps:

[0057] (1) Monitor the instantaneous voltage values ​​of each group of energy storage devices in real time.

[0058] The voltage equalization control strategy described in this invention aims to ensure that the voltage of each group of energy storage devices is consistent. The transmission power adjustment coefficient is calculated in real time based on the magnitude of the voltage relationship and the difference between the voltages of each group of energy storage devices. Therefore, it is necessary to monitor the instantaneous voltage value of each energy storage device in real time.

[0059] (2) Sort the voltage of each group of energy storage devices and configure the power adjustment coefficient of each group of energy storage devices according to the sorting results.

[0060] The voltages of each group of energy storage devices are sorted, and the power adjustment coefficients of each group of energy storage devices are configured according to the voltage ranking results. The configuration method is as follows:

[0061]

[0062] In the formula, the value of k is related to the direction of power transmission. When power flows into the energy storage device, i.e., when the energy storage device is in a charging state, if the voltage of a certain group of energy storage devices is high, it is desirable to reduce the charging power of that group of energy storage devices to make it charge more slowly and the voltage rise more slowly. Conversely, it is desirable to increase the charging power of that group of energy storage devices to make it charge more quickly and the voltage rise more quickly. Therefore, k is negative. When power flows out of the energy storage device, i.e., when the energy storage device is in a discharging state, if the voltage of a certain group of energy storage devices is high, it is desirable to increase the discharging power of that group of energy storage devices to make it discharge more quickly and the voltage drop more quickly. Conversely, it is desirable to reduce the discharging power of that group of energy storage devices to make it discharge more slowly and the voltage drop more slowly. Therefore, k is positive. Moreover, the larger the absolute value of the proportional coefficient k, the higher the voltage equalization efficiency.

[0063] (3) With reference to the power adjustment coefficient, configure the adjustment of the control quantity directly related to the power accordingly;

[0064] By referring to the power adjustment value, the controller reasonably controls the control quantities directly related to the power, thereby realizing the corresponding adjustment of the transmission power of the energy storage device and ultimately achieving the voltage equalization control of the energy storage device.

[0065] Based on the power adjustment coefficient, the adjustment amounts of control quantities directly related to power are configured accordingly.

[0066] The DC / DC converter connecting the energy storage device and the DC distribution network has two operating modes: a) Low-voltage side control mode: The DC distribution network can provide a stable DC voltage for the DC / DC converter. In this mode, the DC / DC converter needs to control the current on the low-voltage side to achieve charging and discharging control of the energy storage device. The low-voltage side control mode includes... Figure 3 As shown; b. High-voltage side control mode: When the DC distribution network cannot provide a stable DC voltage for the DC / DC converter, energy storage devices and the DC / DC converter are needed to jointly support and control the DC voltage of the DC distribution network. The high-voltage side control mode is as follows: Figure 4 As shown. The control strategies differ between the two modes, therefore the voltage equalization control strategies also differ.

[0067] a) Low-voltage side control mode

[0068] In low-voltage side control mode, a stable DC voltage is provided to the DC / DC converter by the DC distribution network. Therefore, the high-voltage side of the DC / DC converter adopts a dual closed-loop control method of submodule capacitor voltage outer loop - current inner loop, while the low-voltage side adopts a single current loop control method. Figure 5 As shown u href The rated operating voltage of the high-voltage side capacitor of the DC / DC submodule, u havg i represents the average voltage of the high-voltage side capacitor of the DC / DC submodule. DCh For DC / DC high-voltage side DC current, u hij Let i be the high-voltage side capacitor voltage of the lower j submodules in the DC / DC submodule corresponding to the i-th energy storage device. DCli is the DC / DC low-voltage side current corresponding to the i-th group of energy storage devices.

[0069] In low-voltage side control mode, the high-voltage side submodule capacitor voltage and low-voltage side current are directly related to the transmission power. Therefore, the transmission power can be adjusted by synchronously adjusting the high-voltage side submodule capacitor voltage and low-voltage side current commands. Based on the calculation results of the transmission power adjustment coefficient according to this invention, the adjustment amount of the high-voltage side submodule capacitor voltage and low-voltage side current command values ​​can be calculated as follows:

[0070]

[0071] Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refiu is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices.

[0072] b. High-voltage side control mode

[0073] In high-voltage side control mode, the DC distribution network loses its DC voltage control capability, requiring a DC / DC converter to take over DC voltage control. Therefore, the high-voltage side of the DC / DC converter adopts a dual closed-loop control method with an outer DC voltage loop and an inner current loop, while the low-voltage side adopts a dual closed-loop control method with an outer submodule capacitor voltage loop and an inner current loop. Figure 6 As shown, u dcref The rated DC voltage on the high-voltage side of the DC / DC converter, u DCh The DC / DC high-voltage side DC bus voltage, u lref The rated operating voltage of the low-voltage side capacitor of the DC / DC submodule, u lavgi This represents the average capacitor voltage of the DC / DC low-voltage side submodule corresponding to the i-th group of energy storage devices.

[0074] The parameters in the diagram are defined as follows:

[0075] u i Let be the terminal voltage of the i-th group of energy storage devices;

[0076] u avg This represents the average terminal voltage of each group of energy storage devices.

[0077] p i The power adjustment values ​​for each group of energy storage devices;

[0078] dLu hi This represents the voltage adjustment value of the capacitor in the high-voltage side submodule under low-voltage side control mode.

[0079] dLi refi This refers to the adjustment value of the energy storage device current command under low-voltage side control mode.

[0080] dHu hi This refers to the voltage adjustment value of the capacitor in the high-voltage side submodule under high-voltage side control mode.

[0081] dHu li This represents the adjustment value of the capacitor voltage of the low-voltage side submodule under high-voltage side control mode.

[0082] u hi This is the high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0083] i refiThis is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0084] u li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0085] u href The rated operating voltage of the high-voltage side capacitor of the DC / DC submodule;

[0086] u havg This represents the average voltage of the high-voltage side capacitor of the DC / DC submodule.

[0087] i DCh This refers to the DC current on the high-voltage side of the DC / DC converter.

[0088] u hij The voltage of the high-voltage side capacitor of the lower j submodules in the DC / DC submodule corresponding to the i-th group of energy storage devices;

[0089] i DCli The DC / DC low-voltage side current corresponding to the i-th group of energy storage devices;

[0090] u dcref The rated DC voltage on the high-voltage side of the DC / DC converter;

[0091] u DCh This refers to the DC bus voltage on the high-voltage side of the DC / DC converter.

[0092] u lref The rated operating voltage of the low-voltage side capacitor of the DC / DC submodule;

[0093] u lavgi This represents the average capacitor voltage of the DC / DC low-voltage side submodule corresponding to the i-th group of energy storage devices.

[0094] In high-voltage side control mode, the capacitor voltages of the high-voltage side submodule and the low-voltage side submodule are directly related to the transmission power. Therefore, the transmission power can be adjusted by adjusting the capacitor voltages of the high-voltage side submodule and the low-voltage side submodule. Based on the calculation results of the transmission power adjustment coefficient according to this invention, the adjustment amount of the capacitor voltages of the high-voltage side submodule and the low-voltage side submodule can be calculated as follows:

[0095]

[0096] Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. liThis is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

[0097] (4) The maximum voltage difference of each group of energy storage devices is judged. When the difference is ≥ △, the controller is used to reasonably control the control quantity directly related to the power to realize the corresponding adjustment of the transmission power of the energy storage device. When the difference is < △, the controller does not act, and finally realizes the balanced control of the voltage of the energy storage device. △ is the threshold of the difference.

[0098] a) Low-voltage side control mode

[0099] In low-voltage side control mode, the maximum voltage difference between each group of energy storage devices is determined. When the difference is ≥ Δ, the controller performs corresponding control on the capacitor voltage of the high-voltage side submodule and the current of the low-voltage side energy storage device, which are directly related to the power. Figure 7 As shown, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This value is added to the low-voltage side current command value. When the difference is less than Δ, the controller does not operate, such as... Figure 5 As shown, this ultimately achieves voltage balance control of the energy storage device under low-voltage side control mode.

[0100] b. High-voltage side control mode

[0101] In high-voltage side control mode, the maximum voltage difference between each group of energy storage devices is determined. When the difference is ≥ Δ, the controller performs corresponding control on the capacitor voltages of the high-voltage side submodule and the low-voltage side submodule, which are directly related to the power, to control the dHu. hi The command value superimposed on the high-voltage side equalization controller will be dHu li This is superimposed on the low-voltage side capacitor voltage command value, such as... Figure 8 As shown; when the difference is less than Δ, the controller does not operate, as shown. Figure 6 As shown, this ultimately achieves voltage balance control of the energy storage device under low-voltage side control mode.

[0102] On the other hand, a voltage equalization control device for an energy storage device is provided, including an acquisition module, an adjustment coefficient determination module, an adjustment amount determination module, and an adjustment control module.

[0103] The acquisition module acquires the instantaneous voltage values ​​of each group of energy storage devices in real time.

[0104] The adjustment coefficient determination module sorts the instantaneous voltage values ​​of each group of energy storage devices and configures the power adjustment coefficient of each group of energy storage devices according to the sorting results.

[0105] The adjustment amount determination module configures the adjustment amount of control quantities directly related to power based on the power adjustment coefficient.

[0106] The control module is adjusted to calculate the maximum value of the instantaneous voltage difference between each group of energy storage devices. If the difference is greater than the set threshold, the power is adjusted according to the adjustment amount determined by the adjustment amount determination module; otherwise, the controller does not adjust the power.

[0107] Furthermore, the adjustment coefficient determination module, according to the voltage u i Sort the data from largest to smallest, and calculate the power adjustment coefficient p. i for:

[0108]

[0109] Where i is the sorting number and k is a constant value for the power adjustment coefficient.

[0110] Furthermore, the adjustment amount determination module configures the adjustment amount of the control quantity directly related to the power, including:

[0111] If it is a low-voltage side control mode, the adjustment amount of the control quantity is:

[0112]

[0113] Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refi u is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices;

[0114] If it is a high-voltage side control mode, the adjustment amount of the control quantity is:

[0115]

[0116] Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

[0117] Further, adjusting the power by adjusting the amount mentioned in the control module includes:

[0118] If it is in low-voltage side control mode, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This is superimposed on the low-voltage side current command value;

[0119] If it is in high-voltage side control mode, dHu hi The command value superimposed on the high-voltage side equalization controller will be dHu li It is superimposed on the low-voltage side capacitor voltage command value.

[0120] In summary, this invention relates to a voltage balancing control method and apparatus for energy storage devices. The method involves real-time monitoring of the instantaneous voltage values ​​of each group of energy storage devices; sorting the instantaneous voltage values ​​of each group of energy storage devices; configuring power adjustment coefficients for each group of energy storage devices based on the sorting results; configuring adjustment amounts for control quantities directly related to power based on the power adjustment coefficients; calculating the maximum value of the difference between the instantaneous voltage values ​​of each group of energy storage devices; if the maximum value exceeds a set threshold, adjusting the power according to the adjustment amount; otherwise, the controller does not adjust the power. This invention ensures voltage balancing across all groups of energy storage devices. It calculates the adjustment amount in real time, but only adjusts when the maximum value of the difference between the instantaneous voltage values ​​of each group of energy storage devices exceeds a threshold, thus avoiding frequent adjustments.

[0121] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A voltage equalization control method for an energy storage device, characterized in that, include: Real-time monitoring of the instantaneous voltage values ​​of each group of energy storage devices; The instantaneous voltage values ​​of each group of energy storage devices are sorted, and the power adjustment coefficient of each group of energy storage devices is configured according to the sorting results. Based on the power adjustment coefficient, configure the adjustment amount of the control quantity directly related to the power; Calculate the maximum value of the instantaneous voltage difference of each group of energy storage devices. If it is greater than the set threshold, adjust the power according to the adjustment amount; otherwise, the controller will not adjust the power. This involves sorting the instantaneous voltage values ​​of each group of energy storage devices, and configuring the power adjustment coefficient for each group of energy storage devices based on the sorting results, including: according to voltage u i Sort in descending order, power adjustment coefficient p i for: Where i is the sorting number and k is a constant value for the power adjustment coefficient; Based on the power adjustment coefficient, configure the adjustment amounts of control quantities directly related to power, including: If it is a low-voltage side control mode, the adjustment amount of the control quantity is: Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refi u is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices; If it is a high-voltage side control mode, the adjustment amount of the control quantity is: Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

2. The voltage equalization control method for energy storage devices according to claim 1, characterized in that, Adjusting the power according to the aforementioned adjustment amount includes: If it is in low-voltage side control mode, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This is superimposed on the low-voltage side current command value; If it is in high-voltage side control mode, dHu hi The command value superimposed on the high-voltage side equalization controller will be dHu li It is superimposed on the low-voltage side capacitor voltage command value.

3. A voltage equalization control device for an energy storage device, characterized in that, include: The acquisition module acquires the instantaneous voltage values ​​of each group of energy storage devices in real time; The adjustment coefficient determination module sorts the instantaneous voltage values ​​of each group of energy storage devices and configures the power adjustment coefficient of each group of energy storage devices according to the sorting results. The adjustment amount determination module configures the adjustment amount of the control quantity directly related to the power based on the power adjustment coefficient; The control module is adjusted to calculate the maximum value of the instantaneous voltage difference of each group of energy storage devices. If it is greater than the set threshold, the power is adjusted according to the adjustment amount determined by the adjustment amount determination module; otherwise, the controller does not adjust the power. Among them, the adjustment coefficient determination module is based on the voltage u. i Sort in descending order, power adjustment coefficient p i for: Where i is the sorting number and k is a constant value for the power adjustment coefficient; The adjustment amount determination module configures the adjustment amounts of control quantities directly related to power, including: If it is a low-voltage side control mode, the adjustment amount of the control quantity is: Where dLu hi For the voltage adjustment of the capacitor of the i-th group of energy storage devices in the high-voltage side submodule, dLi refi u is the adjustment amount of the low-voltage side current command value corresponding to the i-th group of energy storage devices. hi The high-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices, i refi This is the low-voltage side current command value of the DC transformer submodule corresponding to the i-th group of energy storage devices; If it is a high-voltage side control mode, the adjustment amount of the control quantity is: Among them dHu hi dHu represents the voltage adjustment value of the i-th group of energy storage devices in the high-voltage side submodule under high-voltage side control mode. li u represents the capacitor voltage adjustment value of the low-voltage side submodule corresponding to the i-th group of energy storage devices under high-voltage side control mode. li This is the low-voltage side capacitor voltage of the DC transformer submodule corresponding to the i-th group of energy storage devices.

4. The voltage equalization control device for energy storage devices according to claim 3, characterized in that, The adjustment amount of the control module adjusts the power, including: If it is in low-voltage side control mode, dLu hi The command value superimposed on the high-voltage side equalization controller will be dLi refi This is superimposed on the low-voltage side current command value; If it is in high-voltage side control mode, dHu hi The command value superimposed on the high-voltage side equalization controller will be dHu li It is superimposed on the low-voltage side capacitor voltage command value.

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