CN115800421A

CN115800421A - Energy storage system and method for regulating an energy storage system

Info

Publication number: CN115800421A
Application number: CN202211145394.0A
Authority: CN
Inventors: 吴凯; 陈新伟; 颜昱; 但志敏; 李向涛; 姚远
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-09-20
Filing date: 2022-09-20
Publication date: 2023-03-14
Anticipated expiration: 2042-09-20
Also published as: CN115800421B

Abstract

The embodiment of the application provides an energy storage system and an adjusting method of the energy storage system. The energy storage system comprises N battery clusters, an adjusting switch module, M first variable voltage modules and a second variable voltage module, wherein N is a positive integer larger than 1, and M is a positive integer smaller than N; the N battery clusters are mutually connected in parallel, each battery cluster in the N battery clusters is correspondingly connected in series with at least one first variable voltage module in the M first variable voltage modules through at least one regulating switch in the regulating switch modules in a one-to-one mode, the M first variable voltage modules are connected to the second variable voltage module, the second variable voltage module is used for providing voltage for the M first variable voltage modules, and the M first variable voltage modules and the regulating switch modules are used for regulating electrical parameters of the N battery clusters, so that the electrical parameters of the N battery clusters are balanced. The scheme can improve the overall performance of the energy storage system.

Description

Energy storage system and method for regulating an energy storage system

Technical Field

The present embodiments relate to the field of energy storage, and more particularly, to an energy storage system and a method for adjusting the energy storage system.

Background

In a currently mainstream energy storage system, in order to increase energy storage capacity, a plurality of batteries are connected in series to form a battery cluster, and the plurality of battery clusters are directly connected in parallel by a wire. With the increase of the working time, the batteries in the energy storage system slowly have differences, and internal circulation is caused by the voltage difference of the batteries when the batteries are newly added or replaced. This internal circulation can cause further imbalance in the cells in the energy storage system, resulting in reduced performance or even damage to the energy storage system.

In view of this, how to ensure the balance among the battery clusters in the energy storage system to improve the overall performance of the energy storage system is a technical problem to be solved urgently.

Disclosure of Invention

The application provides an energy storage system and an adjusting method of the energy storage system, which can ensure the balance among all battery clusters in the energy storage system, thereby improving the overall performance of the energy storage system.

In a first aspect, an energy storage system is provided, comprising: the system comprises N battery clusters, a regulating switch module, M first variable voltage modules and a second variable voltage module, wherein N is a positive integer larger than 1, and M is a positive integer smaller than N; the N battery clusters are mutually connected in parallel, each battery cluster in the N battery clusters is correspondingly connected in series with at least one first variable voltage module in the M first variable voltage modules in a one-to-one mode through at least one regulating switch in the regulating switch modules, the M first variable voltage modules are connected to a second variable voltage module, the second variable voltage module is used for providing voltage for the M first variable voltage modules, and the M first variable voltage modules and the regulating switch modules are used for regulating electrical parameters of the N battery clusters so that the electrical parameters of the N battery clusters are balanced.

Through the technical scheme of the embodiment of the application, the electrical parameters of the N battery clusters connected in parallel in the energy storage system can be adjusted and balanced through the M first variable voltage modules. On the one hand, the technical scheme can reduce or even avoid the circulation among the N battery clusters, so that the capacity and the performance of the energy storage system can be improved to a large extent, on the other hand, at least two battery clusters in the N battery clusters in the technical scheme can share one first variable voltage module, the number of the first variable voltage modules in the energy storage system is small, and the cost, the size and the weight of the energy storage system can be relatively reduced. In a third aspect, the M first variable voltage modules may share the same second variable voltage module, and on the basis of ensuring the performance of the energy storage system, the overall cost of the energy storage system may be further reduced.

In some possible embodiments, at least one of the N battery clusters is connected in series to a plurality of the M first variable voltage modules through a plurality of regulating switches in a one-to-one correspondence.

In this embodiment, a plurality of first variable voltage modules in the M first variable voltage modules may be connected in series to the same battery cluster through the adjusting switch, and therefore, when the battery cluster is abnormal, any one of the at least two first variable voltage modules may be selected to be adjusted, and the energy storage system has a more flexible adjusting manner for the abnormality of the battery cluster, thereby facilitating the improvement of the overall performance of the energy storage system.

In some possible embodiments, the second variable voltage module is connected to the power source, and the first ends of the N battery clusters are connected to the M first variable voltage modules; the second variable voltage module is used for converting the voltage of the power source into a target voltage, and the ratio of the target voltage to the voltage of the first ends of the N battery clusters is greater than 0 and less than or equal to 10.

In the technical solution of this embodiment, the target voltage converted by the second variable voltage module may be used as the input voltage of the first variable voltage module, and the first variable voltage module may generate the output voltage based on the input voltage, so as to adjust the electrical parameter of the battery cluster connected in series with the first variable voltage module. The ratio of the target voltage to the voltage at the first end of each of the N battery clusters is greater than 0 and less than or equal to 10, so that the M second variable voltage modules can effectively and reliably regulate the N battery clusters based on the target voltage.

In some possible embodiments, a ratio of the target voltage to the voltage of the first terminals of the N battery clusters is greater than or equal to 1 and less than or equal to 5.

In the technical solution of this embodiment, the ratio of the target voltage to the voltage of the first terminals of the N battery clusters is greater than 1 and less than or equal to 5, and the adjustment performance of the second variable voltage module for the battery clusters can be further optimized.

In some possible embodiments, the energy storage system further comprises: the N battery clusters are connected in parallel with the bus bar; the second variable voltage module is connected to the bus bar.

The voltage on the bus bar is generally high, and therefore, the regulation performance of the first variable voltage module can be guaranteed by the conversion of the voltage thereof by the second variable voltage module in this embodiment. Furthermore, the power source of the second variable voltage module is multiplexed as the bus bar of the N battery clusters, so that an additional power source is not needed, and the system cost of the energy storage system can be reduced on the basis of ensuring the adjusting effect of the N battery clusters.

In some possible embodiments, the adjustment switch module comprises X adjustment switches, wherein X is a positive integer less than or equal to N × M.

Through the technical scheme of the embodiment, X adjusting switches are arranged between the N battery clusters and the M voltage variable modules, and the X adjusting switches can flexibly adjust the series connection between the N battery clusters and the M voltage variable modules.

In some possible embodiments, the M first variable voltage modules and the X regulating switches are used for regulating the SOCs of the N battery clusters so as to achieve balance among the SOCs of the N battery clusters; or the M first variable voltage modules and the X regulating switches are used for regulating the voltages of the N battery clusters so as to balance the voltages of the N battery clusters.

Through the technical scheme of the embodiment, the voltage and the SOC of the battery cluster can accurately reflect the state of the battery cluster during charging and discharging, and the battery cluster is easy to monitor by other electrical components, such as a BMS or a BMU. After the voltage or SOC of the N battery clusters is adjusted to be balanced by the M first variable voltage modules, the overall capacity and performance of the N battery clusters can be effectively and greatly improved.

In some possible embodiments, the energy storage system further comprises: a control module; the control module is used for detecting the electrical parameters of each battery cluster in the N battery clusters so as to judge the number of abnormal battery clusters in the N battery clusters; and under the condition that the number of the abnormal battery clusters is K and K is less than or equal to M, the control module is used for controlling K first variable voltage modules in the M first variable voltage modules to operate simultaneously, and the K first variable voltage modules are used for adjusting the electrical parameters of the K abnormal battery clusters.

Through the technical scheme of the embodiment, the abnormal battery clusters can be adjusted by fully utilizing the M first variable voltage modules according to the number of the abnormal battery clusters in the N battery clusters, and the adjustment efficiency of the abnormal battery clusters in the energy storage system is improved.

In some possible embodiments, in the case that the number of the abnormal battery clusters is K, and K is greater than M, the control module is configured to control a target first variable voltage module, corresponding to at least two abnormal battery clusters of the K abnormal battery clusters, of the M first variable voltage modules to operate, and the target first variable voltage module is configured to sequentially adjust electrical parameters of the at least two abnormal battery clusters.

Through the technical scheme of the embodiment, under the condition that the number of abnormal battery clusters in the N battery clusters is larger than M, the control module and the M first variable voltage modules can still adjust the plurality of abnormal battery clusters in the N battery clusters so as to guarantee the capacity and the performance of the energy storage system.

In some possible embodiments, the control module is configured to control the target first variable voltage module to sequentially adjust the electrical parameters of the at least two abnormal battery clusters according to a difference between the electrical parameters of the at least two abnormal battery clusters and a preset threshold.

Through the technical scheme of this embodiment, can further promote energy storage system to wherein a plurality of abnormal battery cluster's regulation performance, be favorable to guaranteeing energy storage system's security.

In some possible embodiments, the energy storage system further comprises: bypass switch module and busbar, this bypass switch module includes: y bypass switches, wherein Y is a positive integer less than M N; each battery cluster in the N battery clusters is connected in series with a bus bar through at least one bypass switch in the Y bypass switches, the at least one bypass switch is connected in series, and the bus bar is used for realizing the transmission of the N battery clusters and external electric energy.

Through the technical scheme of the embodiment, the energy storage system can comprise X regulating switches for controlling the connection and disconnection of the first variable voltage module and the battery clusters, and also comprise Y bypass switches for controlling the transmission of the electric energy between the N battery clusters and the outside. Through the X adjusting switches and the Y bypass switches, N battery clusters in the energy storage system can be adjusted and controlled more flexibly.

In some possible embodiments, each of the N battery clusters is connected in series to the M first variable voltage modules through the M regulating switches in a one-to-one correspondence manner, and each of the N battery clusters is connected in series to the bus bar through the M bypass switches.

Through the technical scheme of this embodiment, every battery cluster in N battery clusters all can be connected in M first variable voltage module and busbar through the same circuit structure, and further, M first variable voltage module also can be connected in N battery clusters through the same circuit structure, is favorable to realizing the equilibrium of circuit structure among the energy storage system.

In some possible embodiments, the ith battery cluster in the N battery clusters is connected in series from the 1 st first variable voltage module to the ith first variable voltage module in the M first variable voltage modules through i regulating switches in a one-to-one correspondence manner, and the ith battery cluster is connected in series to the bus bar through i bypass switches, where i is a positive integer smaller than M; the j-th battery cluster in the N battery clusters is connected in series with the M first variable voltage modules in a one-to-one correspondence mode through the M regulating switches, the j-th battery cluster is connected in series with the bus bar through the M bypass switches, and j is a positive integer larger than or equal to M and smaller than or equal to N.

Through the technical scheme of the embodiment, in the energy storage system, the number of the adjusting switches can be smaller than M x N, and the number of the bypass switches can also be smaller than M x N, so that the manufacturing cost of the energy storage system can be saved.

In some possible embodiments, the N battery clusters include a first battery cluster; under the conditions that the tth adjusting switch connected in series with the first battery cluster is closed and other adjusting switches are opened, and the tth bypass switch connected in series with the first battery cluster is opened and other bypass switches are closed, the tth first variable voltage module connected in series with the tth adjusting switch is used for adjusting the electrical parameters of the first battery cluster, wherein t is a positive integer less than or equal to M; under the condition that all the adjusting switches connected in series with the first battery cluster are switched off and all the bypass switches connected in series with the first battery cluster are switched on, the first battery cluster transmits electric energy with the outside through the bus bar.

Through the technical scheme of the embodiment, the adjusting switch and the bypass switch which are connected in series with the first battery cluster are simply controlled, and the adjustment of the electrical parameters of the first battery cluster and the transmission of the electric energy can be realized. Further, in the process that the first battery cluster transmits electric energy through the bus bar and the outside, all the adjusting switches connected in series with the first battery cluster are turned off, namely, the M first variable voltage modules are in a turned-off state, and reduction of the overall power consumption of the M first variable voltage modules and the energy storage system is facilitated.

In some possible embodiments, the energy storage system further comprises: a control module; before the tth first variable voltage module is used for adjusting the electrical parameters of the first battery cluster, the control module is used for detecting the electrical parameters of the first battery cluster to determine that the first battery cluster is an abnormal battery cluster; the control module is used for controlling the closure of the tth regulating switch connected in series with the first battery cluster and the closure of other regulating switches, the closure of the tth bypass switch connected in series with the first battery cluster and the closure of other bypass switches, and controlling the operation of the tth first variable voltage module so as to regulate the electrical parameters of the first battery cluster; after the electrical parameters of the first battery cluster are adjusted to the preset range, the control module is further used for controlling all the adjusting switches connected in series with the first battery cluster to be switched off, and all the bypass switches connected in series with the first battery cluster to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

According to the technical scheme of the embodiment, the control module can be used for detecting and monitoring the electrical parameters of the first battery cluster, and the first battery cluster can be determined to be an abnormal battery cluster under the condition that the electrical parameters of the first battery cluster exceed the preset range. Further, the control module can control the tth regulating switch, the tth bypass switch, the tth first variable voltage module and the like to regulate the abnormal first battery cluster according to the abnormal information of the first battery cluster, so that the effectiveness and the accuracy of regulation of the first battery cluster are guaranteed. After the adjustment of the t-th first variable voltage module on the abnormal first battery cluster is completed, the t-th first variable voltage module is disconnected with the first battery cluster, and the t-th first variable voltage module does not affect the transmission of electric energy between the first battery cluster and the outside, so that the charge and discharge performance of the first battery cluster is guaranteed.

In some possible embodiments, the electrical parameter is SOC; the control module is used for controlling the operation of the tth first variable voltage module so as to adjust the SOC of the first battery cluster to a preset SOC range.

Through the technical scheme of the embodiment, the SOC of the abnormal first battery cluster can be directly adjusted to the preset SOC range, the capacity of the first battery cluster can be guaranteed to be stable most visually, and the charge and discharge performance of the first battery cluster is effectively guaranteed.

In some possible embodiments, the preset SOC range includes: the average value or the median value of the SOC of the N battery clusters, or the preset SOC range includes: the SOC of any one of the N battery clusters other than the first battery cluster.

Through the technical scheme of the embodiment, the average value or the median of the SOC of the first battery cluster and the SOC of the N battery clusters can be kept balanced, so that the capacity balance among the N battery clusters can be conveniently realized, and the integral charge and discharge performance of the N battery clusters is guaranteed.

In some possible embodiments, the control module is configured to send a current instruction to the tth first variable voltage module, so that the tth first variable voltage module adjusts the current of the first battery cluster to a target current, and the target current adjusts the SOC of the first battery cluster to a target SOC in a preset SOC range.

Through the technical scheme of the embodiment, the control module can directly send a current instruction to the tth first variable voltage module, so that the tth first variable voltage module can output a target current, and the target current can enable the first battery cluster to generate a target SOC meeting the expectation. According to the technical scheme, the SOC of the first battery cluster can be adjusted to be the target SOC in a relatively efficient and reliable mode, and the adjusting efficiency of the energy storage system on the abnormal first battery cluster is improved.

In some possible embodiments, the control module is configured to determine the target current based on a difference between the SOC of the first battery cluster and the target SOC and an average current of the N battery clusters.

According to the technical scheme of the embodiment, the target current comprehensively considers the difference between the SOC of the first battery cluster and the target SOC and the average current of the N battery clusters, so that the target current can more quickly and accurately adjust the SOC of the first battery cluster to the target SOC, and the first battery cluster and other battery clusters are balanced.

In some possible embodiments, the target current I' satisfies the following relation:

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

wherein, I _ave Is the average current of the N battery clusters, Δ SOC is the difference between the SOC of the first battery cluster and the target SOC, k ₁ And n is a predetermined coefficient.

According to the technical scheme of the embodiment, the target current I 'and the target SOC obtained by calculation through the formula can have higher corresponding degree, so that the energy storage system can rapidly adjust the SOC of the first battery cluster to the target SOC according to the target current I', and the adjustment efficiency of the energy storage system to the abnormal battery cluster is improved.

In some possible embodiments, k ₁ And n is related to the power regulation capability of the tth first variable voltage module; and/or, k ₁ And N is related to the over-current capability of the N cell clusters.

Through the technical scheme of the embodiment, the system k is preset in the formula ₁ The numerical value of N considers the power regulation capability of the tth first variable voltage module and/or the overcurrent capability of the N battery clusters, so that the effective adjustment of the tth first variable voltage module on the target current can be ensured, and the safety performance of the energy storage system can be ensured.

in the case where Δ SOC > 0 and the energy storage system is in a state of charge, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

In the case where Δ SOC < 0 and the energy storage system is in a state of charge, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case where Δ SOC > 0 and the energy storage system is in a discharged state, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case where Δ SOC < 0 and the energy storage system is in a discharged state, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

Where Δ SOC is the difference between the SOC of the first battery cluster and the target SOC, I _ave Average current, k, for N cell clusters ₂ Is a preset coefficient.

Through the technical scheme of the embodiment, under the conditions that the difference delta SOC between the SOC of the abnormal battery cluster and the target SOC is different values and the energy storage system is in different states, the control module can determine different target currents I' according to different formulas, the formula is simple to realize, and the average current of N battery clusters is also consideredI _ave Therefore, the abnormal first battery cluster can be adjusted and balanced quickly, and the adjustment efficiency of the energy storage system on the first battery cluster is improved.

In some possible embodiments, the energy storage system further comprises: a control module; before the first battery cluster is connected in parallel with other battery clusters of the N battery clusters, the control module is further used for detecting the electrical parameters of the first battery cluster so as to judge whether to connect the first battery cluster in parallel with other battery clusters.

Through the technical scheme of the embodiment, before the first battery cluster is connected in parallel with other battery clusters, the control module can also judge whether the first battery cluster is connected in parallel according to the electrical parameters of the first battery cluster, so that the overall performance of the energy storage system is ensured. In addition, the regulation capability of the first variable voltage module can be designed within a relatively suitable range without the need for a particularly large design to meet the regulation of the first cell cluster which is abnormally severe, and the cost of the first variable voltage module can be relatively low, thereby facilitating the production and manufacture of the energy storage system.

In some possible embodiments, the electrical parameter is voltage; the control module is used for connecting the first battery cluster to other battery clusters in parallel under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value; and under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than a first preset voltage value, the control module is used for not connecting the first battery cluster to other battery clusters in parallel.

In this embodiment, by detecting the voltage of the first battery cluster, it can be determined and controlled whether the first battery cluster can be connected in parallel to other battery clusters or not more intuitively and rapidly.

In some possible embodiments, in the case that the voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to a first preset voltage value and greater than or equal to a second preset voltage value, the control module is configured to control a tth regulating switch connected in series to the first battery cluster to be turned on and other regulating switches to be turned off, and control a tth first variable voltage module to operate, so that the tth first variable voltage module regulates the voltage of the first battery cluster to a target voltage range; the control module is used for connecting the adjusted first battery cluster in parallel with other battery clusters, controlling all adjusting switches connected in series with the first battery cluster to be switched off, and controlling all bypass switches connected in series with the first battery cluster to be switched on so that the first battery cluster can transmit electric energy with the outside through the bus bar.

Through the technical scheme of the embodiment, on the basis that the control module detects the voltage of the first battery cluster, the control module can further control the first variable voltage module to adjust the voltage of the first battery cluster, so that the first variable voltage module can be connected with other battery clusters in the N battery clusters in parallel, and the capacity and the performance of the energy storage system are guaranteed.

In some possible embodiments, the first preset voltage value is related to a voltage regulation range of the tth first variable voltage module; and/or the target voltage range is related to the average voltage value of the battery clusters which are connected in parallel with each other in the N battery clusters.

Through the technical scheme of the embodiment, the first preset voltage value can be related to the voltage regulation range of the tth first variable voltage module, so that the tth first variable voltage module can support voltage regulation of the first battery cluster. The target voltage range can be related to the average voltage value of the battery clusters which are connected in parallel in the N battery clusters, the first battery cluster can be ensured to be connected in parallel with other battery clusters in the N battery clusters, the voltage of each battery cluster is in a balanced state, and the subsequent normal operation of each battery cluster is facilitated.

In some possible embodiments, the M first variable voltage modules are isolated DC/DC converters or non-isolated DC/DC converters, and/or; the M first variable voltage modules are used for outputting positive voltage and/or negative voltage.

In some possible embodiments, the second variable voltage module is an isolated DC/DC converter or a non-isolated DC/DC converter, and/or; the second variable voltage module is used for outputting positive voltage and/or negative voltage.

Through the technical scheme of the embodiment, the first variable voltage module can be adapted to more application scenes and has better voltage regulation performance.

In a second aspect, a method of regulating an energy storage system is provided, the energy storage system comprising: the adjusting method comprises the following steps that N battery clusters, adjusting switch modules, M first variable voltage modules and a second variable voltage module are connected in parallel, each battery cluster in the N battery clusters is connected in series with at least one first variable voltage module in the M first variable voltage modules in a one-to-one correspondence mode through at least one adjusting switch in the adjusting switch modules, the M first variable voltage modules are connected to the second variable voltage module, the second variable voltage module is used for providing voltage for the M first variable voltage modules, N is a positive integer larger than 1, and M is a positive integer smaller than N, and the adjusting method comprises the following steps: and controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters, so that the electrical parameters of the N battery clusters are balanced.

In some possible embodiments, at least one of the N battery clusters is connected in series to a plurality of first variable voltage modules of the M first variable voltage modules through a plurality of regulating switches in a one-to-one correspondence.

In some possible embodiments, the controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters so that the electrical parameters of the N battery clusters are balanced includes: controlling the M first variable voltage modules and the X regulating switches to regulate the SOC of the N battery clusters, so that the SOC of the N battery clusters are balanced; or the M first variable voltage modules and the X regulating switches are controlled to regulate the voltages of the N battery clusters, so that the voltages of the N battery clusters are balanced.

In some possible embodiments, the adjusting method further comprises: detecting the electrical parameters of each battery cluster in the N battery clusters to judge the number of abnormal battery clusters in the N battery clusters; the above controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters includes: and under the condition that the number of the abnormal battery clusters is K and K is less than or equal to M, controlling K regulating switches connected in series with the K abnormal battery clusters to be closed and K first variable voltage modules in the M first variable voltage modules to operate simultaneously, so that the K first variable voltage modules regulate the electrical parameters of the K abnormal battery clusters.

In some possible embodiments, the controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameter of the N battery clusters further includes: and under the condition that the number of the abnormal battery clusters is K and K is greater than M, at least two abnormal battery clusters in the K abnormal battery clusters are connected in series with the same target first variable voltage module in the M first variable voltage modules through at least two regulating switches, the at least two regulating switches are controlled to be sequentially closed, and the target first variable voltage module is controlled to operate, so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters.

In some possible embodiments, the controlling the at least two regulating switches to be sequentially closed and the target first variable voltage module to operate so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters includes: and controlling the at least two regulating switches to be closed in sequence and the target first variable voltage module to operate according to the difference value between the electrical parameters of the at least two abnormal battery clusters and the preset threshold value, so that the target first variable voltage module can regulate the electrical parameters of the at least two abnormal battery clusters in sequence.

In some possible embodiments, the energy storage system further comprises: bypass switch module and busbar, this bypass switch module includes: each battery cluster in the N battery clusters is connected in series with the bus bar through at least one bypass switch in the Y bypass switches, and the at least one bypass switch is connected in series with each other, wherein Y is a positive integer smaller than M x N; the adjusting method further comprises the following steps: and controlling the Y bypass switches to enable the N battery clusters to carry out electric energy transmission with the outside through the bus bar.

In some possible embodiments, the N battery clusters include a first battery cluster; wherein, the controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters includes: controlling the t-th regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling the t-th bypass switch connected in series with the first battery cluster to be opened and other bypass switches to be closed; controlling a tth first variable voltage module of a tth regulating switch in series connection to regulate the electrical parameter of the first battery cluster, wherein t is a positive integer less than or equal to M; the above-mentioned Y bypass switch of control to make N battery cluster carry out electric energy transmission through busbar and outside, include: and all the adjusting switches connected in series with the first battery cluster are controlled to be switched off, and all the bypass switches connected in series with the first battery cluster are controlled to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

In some possible embodiments, before controlling the tth first variable voltage module to adjust the electrical parameter of the first battery cluster, the adjusting method further includes: and detecting the electrical parameters of the first battery cluster to determine the first battery cluster as an abnormal battery cluster.

In some possible embodiments, the electrical parameter is SOC; wherein, the above-mentioned electrical parameter of controlling the first variable voltage module of the tth that the tth regulating switch is connected in series to adjust the first battery cluster includes: and controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to a preset SOC range.

In some possible embodiments, the controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to the preset SOC range includes: and sending a current instruction to the tth first variable voltage module so that the tth first variable voltage module adjusts the current of the first battery cluster to be a target current, and the target current enables the SOC of the first battery cluster to be adjusted to a target SOC in a preset SOC range.

In some possible embodiments, before sending the current command to the tth first variable voltage module, the adjusting method includes: and determining the target current according to the difference between the SOC of the first battery cluster and the target SOC and the average current of the N battery clusters.

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

in the case where Δ SOC > 0 and the regulation method is in the state of charge, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

In the case of Δ SOC < 0 and the regulating method in the charging state, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case where Δ SOC > 0 and the regulation method is in the discharge state, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case of Δ SOC < 0 and the regulating method in the discharged state, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

In some possible embodiments, before the first battery cluster is connected in parallel to the other battery clusters of the N battery clusters, the adjusting method further includes: detecting an electrical parameter of the first battery cluster; and judging whether the first battery cluster is connected in parallel with other battery clusters or not according to the electrical parameters of the first battery cluster.

In some possible embodiments, the determining whether to connect the first battery cluster to the other battery clusters in parallel according to the electrical parameter of the first battery cluster includes: under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value, connecting the first battery cluster to other battery clusters in parallel; and under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than the first preset voltage value, the first battery cluster is not connected with other battery clusters in parallel.

In some possible embodiments, the connecting the first battery cluster to the other battery clusters in parallel in the case that the voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to the first preset voltage value includes: under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value and larger than or equal to a second preset voltage value, controlling a t-th regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling a t-th first variable voltage module to operate so that the t-th first variable voltage module regulates the voltage of the first battery cluster to a target voltage range; the adjusted first battery cluster is connected in parallel with other battery clusters, all adjusting switches connected in series with the first battery cluster are controlled to be switched off, all bypass switches connected in series with the first battery cluster are controlled to be switched on, and therefore the first battery cluster transmits electric energy with the outside through a bus bar.

Through the technical scheme of the embodiment of the application, the electrical parameters of the N battery clusters connected in parallel in the energy storage system can be adjusted and balanced through the M first variable voltage modules. On the one hand, the technical scheme can reduce or even avoid the circulation among the N battery clusters, so that the capacity and the performance of the energy storage system can be improved to a large extent, on the other hand, at least two battery clusters in the N battery clusters in the technical scheme can share one first variable voltage module, the number of the first variable voltage modules in the energy storage system is small, and the cost, the size and the weight of the energy storage system can be relatively reduced. In a third aspect, the M first variable voltage modules may share the same second variable voltage module, so that the overall cost of the energy storage system can be further reduced on the basis of ensuring the performance of the energy storage system.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 2 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 3 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a first variable voltage module connected in series with a battery cluster through a regulating switch according to an embodiment of the present application.

Fig. 5 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 6 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 7 is a schematic diagram of the connection between the first battery cluster of the N battery clusters and the M first variable voltage modules and the bus bar of the embodiment shown in fig. 6.

Fig. 8 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 9 is another schematic block diagram of an energy storage system provided in an embodiment of the present application.

Fig. 10 is a graph of the change of the SOC of the first battery cluster and the second battery cluster over time in the energy storage system according to the embodiment of the present application.

Fig. 11 is a schematic flow chart diagram of a regulating method of an energy storage system according to an embodiment of the present application.

Fig. 12 is a schematic flow chart diagram of another energy storage system regulation method provided in the embodiment of the present application.

Fig. 13 is a schematic flow chart diagram of another energy storage system regulation method provided in the embodiment of the present application.

Fig. 14 is a schematic flow chart diagram of another energy storage system regulation method provided in the embodiment of the present application.

Fig. 15 is a schematic flow chart diagram of another energy storage system regulation method provided in the embodiment of the present application.

In the drawings, the drawings are not necessarily to scale.

Detailed Description

Embodiments of the present application will be described in further detail below with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the application, but are not intended to limit the scope of the application, i.e., the application is not limited to the described embodiments.

In the description of the present application, it is to be noted that, unless otherwise specified, "a plurality" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like, indicate an orientation or positional relationship that is merely for convenience in describing the application and to simplify the description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. "vertical" is not strictly vertical, but is within the tolerance of the error. "parallel" is not strictly parallel but within the tolerance of the error.

The directional terms used in the following description are intended to refer to directions shown in the drawings, and are not intended to limit the specific structure of the present application. In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood as appropriate by one of ordinary skill in the art.

The term "and/or" in this application is only one kind of association relationship describing the associated object, and means that there may be three kinds of relationships, for example, a and/or B, which may mean: there are three cases of A, A and B, and B. In addition, the character "/" in this application generally indicates that the former and latter related objects are in an "or" relationship.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The battery cluster in the present application refers to a battery assembly in which batteries are connected in series, in parallel, or in a series-parallel manner, where series-parallel means a mixture of series and parallel. For example, the battery cluster in the present application may be formed by a plurality of batteries connected in series or in parallel. For another example, the battery cluster in the present application may be formed by connecting a plurality of batteries in parallel and then in series. A battery refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery may be a battery module or a battery pack.

Optionally, the battery in this embodiment of the present application may be a lithium ion battery, a lithium metal battery, a lead-acid battery, a nickel-insulated battery, a nickel-metal hydride battery, a lithium sulfur battery, a lithium air battery, a sodium ion battery, or the like, which is not specifically limited in this embodiment of the present application.

Currently, in most energy storage systems, the system capacity needs to be increased by connecting the battery clusters in parallel. The wiring and the battery impedance of different battery clusters are generally inconsistent, different battery clusters are directly connected in parallel, a circulation phenomenon can occur in the charging and discharging process, the voltages of the battery clusters are forced to be balanced, and after the electric quantity of the battery cluster with smaller internal resistance is fully charged or emptied, other battery clusters must stop charging and discharging, so that the other battery clusters are not fully charged and emptied, further the capacity loss and the performance reduction of the battery are caused, the battery attenuation is accelerated, and the available capacity of the energy storage system is reduced.

In some related arts, direct parallel connection of the battery clusters is generally achieved by raising a current protection value, that is, direct parallel connection of the battery clusters can be achieved in a case that a current of the battery clusters does not exceed the current protection value. However, this method has the following disadvantages: firstly, the voltage difference of the battery clusters needing to be connected in parallel is ensured to be as small as possible, and if the voltage difference is too large, the impact current is larger than a set overcurrent protection value during parallel connection, so that parallel connection failure can be caused; secondly, a large circulation current still exists between the parallel battery clusters, and the risk of damaging the battery clusters is large.

In view of this, an embodiment of the present application provides an energy storage system, which includes, in addition to a battery cluster connected in parallel, a first variable voltage module, where the first variable voltage module is connected in series to the battery cluster, and is capable of adjusting electrical parameters of the battery cluster, so that the electrical parameters of the battery cluster connected in parallel are balanced, and a circular current between the battery clusters is reduced or even avoided, thereby improving capacity and performance of the energy storage system to a greater extent.

Fig. 1 shows a schematic block diagram of an energy storage system 100 provided by an embodiment of the present application.

As shown in fig. 1, the energy storage system 100 includes: n battery clusters 110, a regulation switch module (e.g., including the regulation switch 130 shown in fig. 1), M first variable voltage modules 120, and one second variable voltage module 170. Wherein N is a positive integer greater than 1, and M is a positive integer less than N.

The N battery clusters 110 are connected in parallel with each other, each battery cluster 110 of the N battery clusters 110 is connected in series to one first variable voltage module 120 of the M first variable voltage modules 120 through one regulating switch 130 of the regulating switch modules, and the M first variable voltage modules 120 are connected to the second variable voltage module 170.

The second variable voltage module 170 is configured to provide a voltage to the M first variable voltage modules 120, and the M first variable voltage modules 120 and the adjustment switch module are configured to adjust electrical parameters of the N battery clusters 110, so that the electrical parameters of the N battery clusters 110 are balanced.

Specifically, each of the N battery clusters 110 may include at least one battery, and the at least one battery may be connected in series with each other or in series-parallel with each other.

Alternatively, as shown in fig. 1, the regulation switch module may include X regulation switches 130, where X is a positive integer less than or equal to N × M. Optionally, in addition to the X adjustment switches 130, the adjustment switch module may also include other components of the user-assisted adjustment switch 130, such as: a capacitor, a resistor, and the like, and the embodiment of the present application does not limit the specific structure of the regulating switch module. In addition, the adjusting switch 130 includes, but is not limited to, a switch structure such as a relay, and the embodiment of the present application does not limit the specific type of the adjusting switch 130.

For each battery cluster 110 of the N battery clusters 110, it may be connected in series with at least one first variable voltage module 120 of the M first variable voltage modules 120 through at least one regulation switch 130 of the X regulation switches 130. Each of the M first variable voltage modules 120 may be connected in series with at least one battery cluster 110.

As an example, in the embodiment shown in fig. 1, each battery cluster 110 of the N battery clusters 110 is connected in series to the M first variable voltage modules 120 in a one-to-one correspondence manner through the M regulating switches 130. Each of the M first variable voltage modules 120 may be connected in series with N battery clusters 110. In this case, M × N regulating switches 130 are included in the energy storage system 100.

In other examples, any one of the N battery clusters 110 may also be connected in series to the a first variable voltage modules 120 through the a regulating switches in a one-to-one correspondence manner, and any one of the M first variable voltage modules 120 may be connected in series to the b battery clusters 110, where a and b are any positive integers smaller than M.

In the embodiment of the present application, it is intended that the M first variable voltage modules 120 are connected in series to the N battery clusters 110 through the X adjusting switches 130, and the specific distribution manner of the X adjusting switches 130 is not limited in the embodiment of the present application.

Specifically, in the embodiment of the present application, since M is smaller than N, at least two battery clusters 110 in the N battery clusters 110 are connected in series to the same first variable voltage module 120 in the M first variable voltage modules 120, so that a larger number of battery clusters 110 can be adjusted by using a smaller number of first variable voltage modules 120, and the cost of the energy storage system 100 is reduced.

As an example, the first variable voltage module 120 may be a Direct Current/Direct Current (DC/DC) converter, an Alternating Current/Direct Current (AC/DC) converter, or the like. The voltage output terminal of the first variable voltage module 120 is connected in series to the battery pack 110, the voltage input terminal of the first variable voltage module 120 is connected to the second variable voltage module 170, and the second variable voltage module 120 is configured to provide an input voltage to the first variable voltage module 120.

Specifically, the voltage input ends of the M first variable voltage modules 120 are connected in parallel, and one end of the parallel connection is commonly connected to the same second variable voltage module 120, so that the second variable voltage module 120 provides the input voltage to the M first variable voltage modules 120.

By way of example and not limitation, the second variable voltage module 170 may be a DC/DC converter, an AC/DC converter, an Alternating Current/Alternating Current (AC/AC) converter, and the like. In some embodiments, the second variable voltage module 170 and the first variable voltage module 120 are both DC/DC converters, and thus may together form a two-stage DC/DC architecture.

For the energy storage system 100 provided in the embodiment of the present application, the second variable voltage module 170 may provide an input voltage to the M first variable voltage modules 120, and the M first variable voltage modules 120 may adjust electrical parameters of the N battery clusters connected in series. For example, the first variable voltage module 120 may adjust the voltage and/or current of the battery cluster 110, and thus adjust other electrical parameters such as the SOC of the battery cluster 110. After being adjusted by the first variable voltage module 120, the electrical parameters of the N battery clusters 110 may be within a preset range. Alternatively, the difference between the electrical parameters of the N cell clusters 110 may be small or even zero.

In summary, according to the technical solution of the embodiment of the present application, the electrical parameters of the N battery clusters 110 connected in parallel in the energy storage system 100 can be adjusted and balanced by the second variable voltage module 170 and the M first variable voltage modules 120. On one hand, the technical scheme can reduce or even avoid the circulation between the N battery clusters, so as to improve the capacity and performance of the energy storage system 100 to a greater extent, and on the other hand, at least two battery clusters 110 in the N battery clusters 110 in the technical scheme can share one first variable voltage module 120, and the number of the first variable voltage modules 120 in the energy storage system 100 is small, so that the cost, the volume and the weight of the energy storage system 100 can be relatively reduced. In a third aspect, the M first variable voltage modules 120 may share the same second variable voltage module 170, so that the overall cost of the energy storage system 100 can be further reduced on the basis of ensuring the performance of the energy storage system 100.

Optionally, in some embodiments, at least one battery cluster 110 of the N battery clusters 110 may be connected in series to a plurality of first variable voltage modules 120 of the M first variable voltage modules 120 in a one-to-one correspondence via a plurality of regulating switches 130.

In other words, in this embodiment, a plurality of first variable voltage modules 120 in the M first variable voltage modules 120 may be connected in series to the same battery cluster 110 through the adjusting switch 130, so that when an abnormality occurs in the battery cluster 110, any one of the at least two first variable voltage modules 120 may be selected to be adjusted, and the energy storage system 100 has a more flexible adjusting manner for the abnormality of the battery cluster 110, thereby facilitating to improve the overall performance of the energy storage system 100.

Fig. 2 shows another schematic structural diagram of the energy storage system 100 provided in the embodiment of the present application.

As shown in fig. 2, the power source 171 is used for providing voltage to the second variable voltage module 170, the second variable voltage module 170 is connected to the M first variable voltage modules 120, and the M first variable voltage modules 120 are connected to the N battery clusters 110.

It should be noted that fig. 2 can be understood as a simplified schematic diagram of fig. 1, and fig. 2 is intended to illustrate the voltage relationship among the second variable voltage module 170, the first variable voltage module 120, and the battery cluster 110, therefore, other components of the energy storage system 100, such as the regulating switch 130, are not shown in detail in fig. 2, and the specific embodiment of the regulating switch 130 can still refer to the above description of the embodiment shown in fig. 1.

Optionally, in the embodiment of the present application, the power source 171 of the environment in which the energy storage system 100 is located is generally a high-voltage power source, and the power source 171 may also be referred to as a high-voltage end. The voltage of the battery cluster 110 connected in series with the end of the second variable voltage module 120 is generally lower, and the end of the battery cluster 110 connected in series with the second variable voltage module 120 can also be called a low voltage end. In order to realize the adjustment function of the battery cluster 110 (low voltage end), the power source 171 generally needs to perform a first-stage voltage reduction process by the first variable voltage module 170, so that the second variable voltage module 120 can effectively and safely adjust the electrical parameters such as the voltage and the current of the battery cluster 110.

Alternatively, in the case that the power source 171 is small, the first variable voltage module 170 may also flexibly perform the boost adjustment on the voltage of the power source 171, so as to achieve the effective and reliable adjustment of the second variable voltage module 120 on the battery cluster 110.

In some embodiments, the second variable voltage module 170 is connected to the power source 171, the first terminals of the N battery clusters 110 are connected to the M first variable voltage modules 120, and the second variable voltage module 170 is configured to convert the voltage of the power source 171 into a target voltage, and a ratio of the target voltage to the voltage of the first terminals of the N battery clusters 110 is greater than 0 and less than or equal to 10.

Specifically, in this embodiment, the target voltage converted by the second variable voltage module 170 may be used as the input voltage of the first variable voltage module 120, and the first variable voltage module 120 may generate the output voltage based on the input voltage, so as to adjust the electrical parameter of the battery cluster 110 connected in series therewith.

The ratio of the target voltage to the voltage of the first end of each of the N battery clusters 110 is greater than 0 and less than or equal to 10, so that the M second variable voltage modules 120 can effectively and reliably regulate the N battery clusters 110 based on the target voltage.

Further, the ratio of the target voltage to the voltages of the first terminals of the N battery clusters 110 is greater than 1 and less than or equal to 5, which can further optimize the regulation performance of the second variable voltage module 120 for the battery clusters 110.

On the basis of the embodiment shown in fig. 1, fig. 3 shows another schematic structural diagram of the energy storage system 100 provided by the embodiment of the present application.

As shown in fig. 3, in the embodiment of the present application, the energy storage system 100 further includes: the bus bar 160, the n cell clusters 110 are connected in parallel to the bus bar 160. The second variable voltage module 170 is connected to the bus bar.

Specifically, in the embodiment of the present application, the power source of the second variable voltage module 170 may be the bus bar. The bus bar 160 may realize power transmission between the N battery clusters 110 and the outside.

The voltage on the bus bar 160 is generally high, and therefore, the voltage conversion by the second variable voltage module 170 in the embodiment of the present application can ensure the regulation performance of the first variable voltage module 120. Further, the power source of the second variable voltage module 170 is multiplexed as the bus bar of the N battery clusters 110, and no additional power source is needed, so that the system cost of the energy storage system 100 can be reduced on the basis of ensuring the adjustment effect on the N battery clusters 110.

Optionally, in some embodiments, the M first variable voltage modules 120 and the X adjusting switches 130 are used to adjust states of Charge (SOCs) of the N battery clusters to achieve balance among SOCs of the N battery clusters 110.

Alternatively, in other embodiments, the M first variable voltage modules 120 and the X adjustment switches 130 are used to adjust the voltages of the N battery clusters 110 to achieve equalization between the voltages of the N battery clusters.

Specifically, the output voltage of the first variable voltage module 120 is adjustable, and after the output voltage of the first variable voltage module 120 is adjusted, the current of the battery cluster 110 connected in series with the first variable voltage module is adjustable, so that other electrical parameters such as the voltage and the SOC of the battery cluster 110 are correspondingly changed.

Fig. 4 shows a schematic diagram of a first variable voltage module 120 connected in series with a battery cluster 110 via a regulating switch 130.

As shown in fig. 4, the battery cluster 110 is formed by connecting a plurality of cells 111 in series. The voltage of the battery cluster 110 is denoted as U _bat The voltage of the first variable voltage module 120 is denoted as U _dcdc The first variable voltage module 120 and the battery cluster 110 can be connected in series between bus bars, the bus bar voltage being denoted as U _bus 。

When the regulating switch 130 is closed, the current I = (U) of the battery cluster 110 during charging of the energy storage system 100 _bus -U _dcdc -U _bat ) R; during the discharging process of the energy storage system 100, the current I = (U) of the battery cluster 110 _dcdc +U _bat -U _bus ) and/R. Where R is the total of the series branches formed by the first variable voltage module 120 and the battery cluster 110And (4) resistance. The total resistance R may include the resistance of the battery cluster 110, the resistance of the first variable voltage module 120, the resistance of the regulating switch 130, the resistance of the connection lines, and so on, wherein the resistance of the battery cluster 110 is large.

Therefore, when the voltage of the first variable voltage module 120 is adjusted, the current of the battery cluster 110 is also adjusted and changed, and other electrical parameters of the battery cluster 110, such as the voltage and the SOC, are also adjusted and changed accordingly.

The voltage and the SOC of the Battery cluster 110 can accurately reflect the state of the Battery cluster 110 during charging and discharging, and are easily monitored by other electrical components, such as a Battery Management System (BMS) or a Battery Management Unit (BMU). After the M first variable voltage modules 120 adjust the voltages or SOCs of the N battery clusters 110 to be balanced, the overall capacity and performance of the N battery clusters 110 can be effectively and greatly improved.

Optionally, in some embodiments, the first variable voltage module 120 is an isolated DC/DC converter or a non-isolated DC/DC converter, and/or the first variable voltage module 120 is configured to output a positive voltage and/or a negative voltage.

Optionally, in some embodiments, the second variable voltage module 170 may also be an isolated DC/DC converter or a non-isolated DC/DC converter, and/or the second variable voltage module 170 may also be configured to output a positive voltage and/or a negative voltage.

Through the technical scheme of the embodiment, the first variable voltage module 120 can be adapted to more application scenarios and has better voltage regulation performance.

Fig. 5 shows another schematic block diagram of the energy storage system 100 provided in the embodiment of the present application.

As shown in fig. 5, in the embodiment of the present application, the energy storage system 100 further includes: a control module 150, wherein the control module 150 is configured to detect an electrical parameter of each battery cluster 110 of the N battery clusters 110 to determine the number of abnormal battery clusters 110 in the N battery clusters 110. When the number of the abnormal battery clusters is K and K is less than or equal to M, the control module 150 is configured to control K first variable voltage modules 120 of the M first variable voltage modules 120 to operate simultaneously, where the K first variable voltage modules are configured to adjust electrical parameters of the K abnormal battery clusters.

Specifically, in the embodiment of the present application, the N battery clusters 110 in the energy storage system 100 may be in an operating state, for example, the N battery clusters 110 may be in a charging state or a discharging state.

During the operation state of the N battery clusters 110, the control module 150 may be configured to detect, in real time, operation parameters of the N battery clusters 110 in the N battery clusters 110, where the operation parameters may include operation electrical parameters of the battery clusters 110, such as voltage, current, or SOC. Based on the operating electrical parameters of the N battery clusters 110 in the N battery clusters 110, the number of abnormal battery clusters in the N battery clusters 110 may be determined, where an abnormal battery cluster may be a battery cluster whose operating electrical parameters exceed a preset threshold.

In the case that the number of abnormal battery clusters in the N battery clusters 110 is less than or equal to M, it indicates that the M first variable voltage modules 120 can operate simultaneously to adjust the abnormal battery clusters in the N battery clusters 110.

Specifically, there are K abnormal battery clusters in the N battery clusters 110, and the control module 150 may control the K first variable voltage modules 120 corresponding to the K abnormal battery clusters to operate, so as to adjust electrical parameters of the K abnormal battery clusters. The K first variable voltage modules 120 corresponding to the K abnormal battery clusters may be understood as the first variable voltage modules 120 connected in series to the K abnormal battery clusters through the regulating switch 130.

In some embodiments, the number of the first variable voltage modules 120 connected in series to the K abnormal battery clusters through the regulating switch 130 may be greater than K, for example, there may be M first variable voltage modules 120 connected in series to the K abnormal battery clusters through the regulating switch 130, in which case, the K first variable voltage modules 120 may be arbitrarily selected among the M first variable voltage modules or the K first variable voltage modules 120 may be selected according to a certain rule to respectively regulate the K abnormal battery clusters.

It is understood that the control module 150 may control not only the K first variable voltage modules 120 to operate, but also the K regulating switches 130 connected in series between the K abnormal battery clusters and the K first variable voltage modules 120 to be closed, so that the K first variable voltage modules 120 regulate the K abnormal battery clusters.

Optionally, the control module 150 includes but is not limited to a BMS or a BMU. The BMS or BMU may monitor operating parameters of each battery cluster 110 and other components in the energy storage system 100 and control the regulating switch 130, the first variable voltage module 120, etc. in the energy storage system 100 according to the operating parameters.

Through the technical scheme of the embodiment of the application, the abnormal battery clusters can be adjusted by fully utilizing the M first variable voltage modules 120 according to the number of the abnormal battery clusters in the N battery clusters 110, and the adjustment efficiency of the abnormal battery clusters in the energy storage system 100 is improved.

Optionally, in a case that the number of abnormal battery clusters in the N battery clusters 110 is K and K is greater than M, the control module 150 is configured to control a target first variable voltage module corresponding to at least two abnormal battery clusters in the K abnormal battery clusters in the M first variable voltage modules 120 to operate, where the target first variable voltage module is configured to sequentially adjust electrical parameters of the at least two abnormal battery clusters. Here, the target first variable voltage module corresponding to the at least two abnormal battery clusters may be understood as the first variable voltage module 120 connected in series to the at least two abnormal battery clusters through the regulating switch 130.

Specifically, in K abnormal battery clusters of the N battery clusters 110, since K is greater than M, at least two abnormal battery clusters of the K abnormal battery clusters are connected in series to the same target first variable voltage module. The target first variable voltage module may sequentially adjust the at least two abnormal battery clusters.

Optionally, in some embodiments, the energy storage system 100 may include a plurality of target first variable voltage modules, at least two abnormal battery clusters may be connected in series to the plurality of target first variable voltage modules through the regulating switch 130, and any one of the plurality of first target variable voltage modules may regulate the at least two abnormal battery clusters in sequence.

Optionally, the control module 150 may be configured to control the target first variable voltage module to sequentially adjust the electrical parameters of the at least two abnormal battery clusters according to a difference between the electrical parameters of the at least two abnormal battery clusters and a preset threshold.

In some embodiments, the target first variable voltage module adjusts a more abnormal battery cluster of the at least two abnormal battery clusters first. For example, in at least two abnormal battery clusters, if the deviation of the electrical parameter of a certain abnormal battery cluster from the preset threshold value is the largest, the abnormal battery cluster is the most abnormal battery cluster of the at least two abnormal battery clusters.

Through the technical scheme of the embodiment, when the number of abnormal battery clusters in the N battery clusters 110 is greater than M, the control module 150 and the M first variable voltage modules 120 can still adjust a plurality of abnormal battery clusters in the N battery clusters 110, so as to ensure the capacity and performance of the energy storage system 100.

Fig. 6 shows another schematic block diagram of the energy storage system 100 provided in the embodiment of the present application.

As shown in fig. 6, in the embodiment of the present application, in addition to the N battery clusters 110, the X regulating switches 130, and the M first variable voltage modules 120 in the above embodiment, the energy storage system 100 further includes: a bypass switch module and a bus bar 160, the bypass switch module comprising: y bypass switches 140, where Y is a positive integer less than or equal to M x N.

Optionally, in the bypass switch module, in addition to the Y bypass switches 140, the bypass switch module may further include other components of the user auxiliary bypass switch 140, such as: a capacitor, a resistor, and the like, and the embodiment of the present application does not limit the specific structure of the regulating switch module. In addition, the bypass switch 140 includes, but is not limited to, a switch structure such as a relay, and the embodiment of the present application does not limit the specific type of the bypass switch 140.

Each battery cluster 110 of the N battery clusters 110 is connected in series to the bus bar 160 through at least one bypass switch 140 of the Y bypass switches 140, the at least one bypass switch 140 is connected in series, and the bus bar 160 is used for realizing electric energy transmission between the N battery clusters 110 and the outside.

Specifically, in the embodiment shown in fig. 6, the positive electrodes and the negative electrodes of the N battery clusters 110 are connected to two bus bars 160, respectively. The two bus bars 160 may be the first bus bar 1601 and the second bus bar 1602 in the embodiment shown in fig. 3. The N battery clusters 110 may be discharged to the outside through the two bus bars 160, or an external power source may charge the N battery clusters 110 through the two bus bars.

Alternatively, each cell cluster 110 of the N cell clusters 110 may be connected to any one bus bar 160 of the two bus bars 160 through at least one bypass switch 140 connected in series. For example, at least one bypass switch 140 is connected in series between one bus bar 160 and the positive pole of one cell cluster 110, or at least one bypass switch 140 is connected in series between one bus bar 160 and the negative pole of one cell cluster 110.

Through the technical solution of the embodiment of the present application, the energy storage system 100 may further include Y bypass switches 140 for controlling the transmission of the electric energy between the N battery clusters 110 and the outside, in addition to the X adjustment switches 130 for controlling the connection and disconnection between the first variable voltage module 120 and the battery cluster 110. Through the X adjusting switches 130 and the Y bypass switches 140, the N battery clusters 110 in the energy storage system 100 can be adjusted and controlled more flexibly.

As an example, as shown in fig. 6, each of the N battery clusters 110 is connected in series to the M first variable voltage modules 120 through the M regulating switches 130 in a one-to-one correspondence manner, and each of the N battery clusters 110 is connected in series to the bus bar 160 through the M bypass switches 140.

Specifically, in this example, the energy storage system 100 includes M × N regulation switches 130 and M × N bypass switches 140.

For any one of the N battery clusters 110, the battery cluster 110 may be connected in series to one end of the M first variable voltage modules 120 through the M adjusting switches 130. When any one of the N battery clusters 110 is abnormal, any one of the M first variable voltage modules 120 may provide regulation for the any one of the N battery clusters 110.

In addition, for any one of the N battery clusters 110, the battery cluster 110 may be connected in series to the bus bar 160 through the M bypass switches 140. The M bypass switches 140 are connected in series, and may correspond to the M adjusting switches 130 one by one, and the bypass switches 140 and the adjusting switches 130 corresponding to each other are connected in parallel.

As an example, among the M bypass switches 140 connected in series to any one of the battery clusters 110, the pth bypass switch may be connected in series to one end of the pth first variable voltage module corresponding thereto. The other end of the pth first variable voltage module is connected in series with a pth adjusting switch of the M adjusting switches 130, and the pth adjusting switch and the pth bypass switch are connected in parallel. Where p is a positive integer less than or equal to M, and when p =1, the 1 st bypass switch of the M bypass switches 140 is the switch closest to the battery cluster 110. The 1 st bypass switch and the 1 st adjusting switch are connected in parallel and then directly connected in series with the battery cluster 110.

When p is larger than 1, the p regulating switch and the p bypass switch corresponding to the p first variable voltage module can be connected in series with the p-1 regulating switch and the p-1 bypass switch corresponding to the p-1 first variable voltage module.

Through the technical scheme of this example, each battery cluster 110 in the N battery clusters 110 can be connected to the M first variable voltage modules 120 and the bus bar 160 through the same circuit structure, and further, the M first variable voltage modules 120 can also be connected to the N battery clusters 110 through the same circuit structure, which is favorable for achieving the balance of the circuit structure in the energy storage system 100. Through the technical scheme of this example, in addition to the adjustment and the electric energy transmission of the N battery clusters 110 through the M × N adjusting switches 130 and the M × N bypass switches 140, the method is beneficial to improving the balance of the energy storage system 100, and is convenient for adjusting the abnormal battery clusters 110 in the energy storage system 100.

Fig. 7 shows a schematic connection diagram of a first cell cluster 1101 of the N cell clusters 110 with the M first variable voltage modules 120 and the bus bar 160 of the embodiment shown in fig. 6. Alternatively, the first cell cluster 1101 may be any one cell cluster 110 of the N cell clusters 110.

As shown in fig. 7, M first variable voltage modules 120 connected in series in the first battery cluster 1101 are respectively represented as 1201 to 120M, wherein the tth first variable voltage module is represented as 120t, t is a positive integer less than or equal to M. The regulating switch 130 and the bypass switch 140 connected in series to the 1 st first variable voltage module 1201 are respectively denoted as a 1 st regulating switch 1301 and a 1 st bypass switch 1401, and similarly in this order, the regulating switch 130 and the bypass switch 140 connected in series to the t-th first variable voltage module 120t are respectively denoted as a t-th regulating switch 130t and a t-th bypass switch 140t.

In the case that the tth regulating switch 130t connected in series to the first battery cluster 1101 is closed and the other regulating switches are open, the tth bypass switch 140t connected in series to the first battery cluster 1101 is open and the other bypass switches are closed, the tth first variable voltage module 120t connected in series to the tth regulating switch 130t is used to regulate the electrical parameter of the first battery cluster 1101.

In the case where all the regulation switches 1301 to 130M connected in series to the first battery cluster 1101 are open and all the bypass switches 1401 to 140M connected in series to the first battery cluster are closed, the first battery cluster 1101 transmits electric power to the outside through the bus bar 160.

Through the technical scheme of the embodiment of the application, the M adjusting switches 130 and the M bypass switches 140 connected in series to the first battery cluster 1101 are simply controlled, so that the adjustment of the electrical parameters of the first battery cluster 1101 and the transmission of the electric energy can be realized. Further, in the process that the first battery cluster 1101 transmits electric energy to the outside through the bus bar 160, all the regulating switches connected in series to the first battery cluster 1101 are turned off, that is, all the M first variable voltage modules 120 are in an off state, which is beneficial to reducing the overall power consumption of the M first variable voltage modules 120 and the energy storage system 100.

Fig. 8 shows another schematic block diagram of the energy storage system 100 provided in the embodiment of the present application.

As shown in fig. 8, in the embodiment of the present application, the ith battery cluster in the N battery clusters 110 is connected in series to the 1 st to the ith first variable voltage modules in the M first variable voltage modules 120 through the i regulating switches 130 in a one-to-one correspondence manner, and the ith battery cluster is connected in series to the bus bar 160 through the i bypass switches 140, where i is a positive integer smaller than M.

The jth battery cluster of the N battery clusters 110 is connected in series to the M first variable voltage modules 120 in a one-to-one correspondence manner through the M regulating switches 130, and the jth battery cluster is connected in series to the bus bar through the M bypass switches 140, where j is a positive integer greater than or equal to M and less than or equal to N.

Specifically, in the embodiment of the present application, not each of the N battery clusters 110 is connected in series to the M first variable voltage modules 120 through the M regulating switches 130, nor is each of the battery clusters 110 connected in series to the bus bar 160 through the M bypass switches 140. In the energy storage system 100 provided in the embodiment of the present application, the number of the adjusting switches 130 may be less than M × N, and the number of the bypass switches 140 may also be less than M × N, so that the manufacturing cost of the energy storage system 100 may be saved.

Specifically, among the N battery clusters 110, the first M battery clusters 110 may be connected to the first variable voltage module 120 and the bus bar 160 through a smaller number of the regulating switches 130 and the bypass switches 140. As an example, the 1 st cell cluster may be connected in series to the 1 st first variable voltage module through only one regulating switch 130, and connected in series to the bus bar 160 through only one bypass switch 140; by analogy, the ith battery cluster can be connected in series from the 1 st first variable voltage module to the ith first variable voltage module through the i adjusting switches 130, and can be connected in series to the bus bar 160 through the i bypass switches 140, where i is any positive integer less than or equal to M.

Among the i bypass switches 140 connected in series with the ith battery cluster, the pth bypass switch may be connected in series to one end of a pth first variable voltage module corresponding thereto, and the other end of the pth first variable voltage module is connected in series to a pth adjusting switch among the i adjusting switches 130, and the pth adjusting switch and the pth bypass switch are connected in parallel to each other. Where p is a positive integer less than or equal to i, and when p =1, the 1 st bypass switch of the i bypass switches 140 is the switch closest to the i-th cell cluster. The 1 st bypass switch and the 1 st adjusting switch 130 are connected in parallel and then directly connected in series with the ith battery cluster.

When p > 1, the pth adjusting switch 130 and the pth bypass switch 140 corresponding to the pth first variable voltage module 120 may be connected in series to the pth-1 adjusting switch 130 and the pth-1 bypass switch 140 corresponding to the pth-1 first variable voltage module 120.

Among the N battery clusters 110, each battery cluster 110 of the next N-M battery clusters 110 may be connected to the first variable voltage module 120 and the bus bar 160 through M regulating switches 130 and M bypass switches 140. The specific related scheme of each battery cluster 110 in the next N-M battery clusters 110 may refer to the related description of the embodiments shown in fig. 6 to fig. 7, and will not be described herein again.

For the control manner of the adjusting switch 130 and the bypass switch 140 corresponding to each battery cluster 110 in the embodiment of the present application, reference may also be specifically made to the related description of the embodiment shown in fig. 7, and redundant description is not repeated here.

On the basis of the embodiment shown in fig. 8, fig. 9 shows another schematic block diagram of the energy storage system 100 provided by the embodiment of the present application.

As shown in fig. 9, in an embodiment of the present application, the energy storage system 100 may include the control module 150 of the embodiment shown in fig. 5 above.

Specifically, before the tth first variable voltage module of the M first variable voltage modules 120 is used to adjust the electrical parameter of the first battery cluster, the control module 150 is used to detect the electrical parameter of the first battery cluster to determine that the first battery cluster is an abnormal battery cluster. The control module 150 is configured to control the tth adjusting switch connected in series to the first battery cluster to be turned on and other adjusting switches to be turned off, and the tth bypass switch connected in series to the first battery cluster to be turned off and other bypass switches to be turned on, and control the tth first variable voltage module to operate to adjust the electrical parameter of the first battery cluster.

In the embodiment of the present application, the tth first variable voltage module is any one of the first variable voltage modules 120 connected in series to the first battery cluster. The control module 150 can detect and monitor the electrical parameter of the first battery cluster, and when the electrical parameter of the first battery cluster exceeds a preset range, the first battery cluster can be determined to be an abnormal battery cluster. Further, the control module 150 may control the tth first variable voltage module and the tth regulating switch, the tth bypass switch, etc. connected in series to the tth first variable voltage module to regulate the abnormal first battery cluster according to the abnormal information of the first battery cluster, so as to ensure the effectiveness and accuracy of regulation of the first battery cluster.

After the electrical parameter of the first battery cluster is adjusted to the preset range, the control module 150 is further configured to control all the adjusting switches connected in series to the first battery cluster to be turned off, and all the bypass switches connected in series to the first battery cluster to be turned on, so that the first battery cluster transmits electric energy to the outside through the bus bar 160.

Through the technical scheme of the embodiment, after the adjustment of the tth first variable voltage module on the abnormal first battery cluster is completed, the tth first variable voltage module is disconnected with the first battery cluster, and the tth first variable voltage module does not affect the transmission of electric energy between the first battery cluster and the outside, so that the charge and discharge performance of the first battery cluster is guaranteed.

In some possible embodiments, the electrical parameter may be SOC, and the control module 150 may be configured to control the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to a preset SOC range.

Optionally, in some examples, the preset SOC range may include: the average or median value of the SOC of the N battery clusters. Alternatively, the central value of the preset SOC range may be an average value or a median value of the SOCs of the N battery clusters.

Through the technical scheme of the example, the average value or the median of the SOC of the first battery cluster and the SOC of the N battery clusters 110 can be kept balanced, so that the capacity balance among the N battery clusters 110 can be realized more conveniently, and the overall charge and discharge performance of the N battery clusters 110 is guaranteed.

Alternatively, in other examples, the preset SOC range may include: and the SOC of any one battery cluster except the first battery cluster in the N battery clusters. Alternatively, the central value of the preset SOC range may be the SOC of any one of the N battery clusters except the first battery cluster.

Through the technical scheme of the example, the SOC of the first battery cluster and the SOC of other battery clusters can be kept balanced, and the charge and discharge performance of the first battery cluster and the other battery clusters is guaranteed.

Optionally, the control module 150 may be configured to send a current instruction to the tth first variable voltage module, so that the tth first variable voltage module adjusts the current of the first battery cluster to a target current, where the target current adjusts the SOC of the first battery cluster to a target SOC in a preset SOC range.

As an example, the target SOC may be an average value or a median value of the SOCs of the N battery clusters 110, or the target SOC may be the SOC of any one of the N battery clusters except for the first battery cluster.

Specifically, the control module 150 may send a current command to the tth first variable voltage module, and the tth first variable voltage module may adjust its own voltage and current according to the current command, thereby adjusting the current of the first battery cluster connected in series with the tth first variable voltage module. Since the current of the first battery cluster changes and the SOC of the first battery cluster also changes, the control module 150 may monitor the SOC of the first battery cluster in real time to determine whether the SOC of the first battery cluster is adjusted to the target SOC.

Through the technical scheme of the embodiment of the application, the control module 150 can directly send a current instruction to the tth first variable voltage module, so that the tth first variable voltage module can output a target current, and the target current can enable the first battery cluster to generate a target SOC meeting the expectation. According to the technical scheme, the SOC of the first battery cluster can be adjusted to be the target SOC in a highly efficient and reliable mode, and the adjusting efficiency of the energy storage system 100 on the abnormal first battery cluster is improved.

In some embodiments, the control module 150 may be configured to determine the target current based on a difference between the SOC of the first battery cluster and the target SOC and an average current of the N battery clusters 110.

In this embodiment, the target current comprehensively considers the difference between the SOC of the first battery cluster and the target SOC and the average current of the N battery clusters 110, so that the target current can more quickly and accurately adjust the SOC of the first battery cluster to the target SOC, and the first battery cluster is equalized with other battery clusters.

As an example, the target current I' may satisfy the following relation:

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

wherein, I _ave Is the average current of the N battery clusters 110, Δ SOC is the difference between the SOC of the first battery cluster and the target SOC, k ₁ And n is a predetermined coefficient.

In the solution of this embodiment, the control module 150 may determine the target current I' according to the formula, which determines the current variation f (Δ SOC) by using the exponential function and the Δ SOC, and then determines the average current I of the N battery clusters 110 _ave The target current I' is determined with the current variation f (Δ SOC).

The target current I 'calculated by the formula has higher degree of correspondence with the target SOC, so that the energy storage system 100 can rapidly adjust the SOC of the first battery cluster to the target SOC according to the target current I', and the adjustment efficiency of the energy storage system 100 on the abnormal battery cluster is improved.

Alternatively, in the above formula, the coefficient k is preset ₁ And n and t first variable voltage modulesThe power regulating capability is related, and/or the preset coefficient k ₁ And N is related to the over-current capability of the N cell clusters 110.

In particular, the power regulation capability of the tth first variable voltage module may depend on the maximum output power and the minimum output power of the tth first variable voltage module. The over-current capability of the N battery clusters 110 may depend on the maximum current that each battery cluster 110 of the N battery clusters 110 can withstand.

Optionally, with a preset coefficient k ₁ And n is increased, the following two conditions are ensured: (1) The tth first variable voltage module needs to satisfy the power regulation capability of the corresponding current variation. (2) The total power of the energy storage system 100 in a specific mode is constant, when the current of the first battery cluster is independently adjusted, the other battery clusters passively adjust the current to meet the total power, and when the current of the first battery cluster is adjusted, not only the overcurrent capacity of the current of the first battery cluster but also the overcurrent capacity of the current of the other battery clusters after being affected need to be noticed.

Through the technical scheme of the embodiment, the system k is preset in the formula ₁ The value of N takes into account the power regulation capability of the tth first variable voltage module and/or the overcurrent capability of the N battery clusters, so that on one hand, the effective adjustment of the tth first variable voltage module on the target current can be ensured, and on the other hand, the safety performance of the energy storage system 100 can also be ensured.

As another example, the target current I' may satisfy the following relation:

in the case where Δ SOC > 0 and the energy storage system 100 is in the charged state, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

In the case where Δ SOC < 0 and the energy storage system 100 is in the state of charge, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case where Δ SOC > 0 and the energy storage system 100 is in a discharge state, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

At Δ SOC < 0 and energy storage system 100 is dischargingIn the case of the state, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

Wherein Δ SOC is a difference between the SOC of the first battery cluster and a predetermined SOC, I _ave Average current, k, for N cell clusters ₂ Is a preset coefficient.

Through the technical scheme of the embodiment of the application, under the condition that the difference delta SOC between the SOC of the abnormal battery cluster and the target SOC is different values and the energy storage system 100 is in different states, the control module 150 can determine different target currents I' according to different formulas, the formula is simpler to implement, and the average current I of the N battery clusters 110 is also considered _ave Therefore, the abnormal first battery cluster can be adjusted and balanced quickly, and the adjustment efficiency of the energy storage system 100 on the first battery cluster is improved.

Through the two current regulation modes, when the energy storage system 100 is charged, the charging of the battery cluster 110 with higher capacity can be slowed down or the charging of the battery cluster 110 with lower capacity can be quickened. When the energy storage system 100 is discharging, the battery clusters 110 with higher capacity can be discharged faster or the battery clusters 110 with lower capacity can be discharged slower.

Fig. 10 shows a graph of the SOC of the first battery cluster and the second battery cluster in the energy storage system 100 over time.

Specifically, the energy storage system 100 may be in a state of charge, wherein the SOC of the first and second battery clusters may gradually increase over time.

In the case where the control module 150 detects that the first battery cluster is an abnormal battery cluster and the charging rate of the first battery cluster is fast, the control module 150 may determine at t ₁ The first battery cluster is adjusted at every moment so that the charging rate of the first battery cluster becomes slow, namely the increase rate of the SOC of the first battery cluster becomes slow along with the time. The SOC of the first battery cluster and the SOC of the second battery cluster can be both at t ₂ The time reaches 80%.

In the embodiment shown in fig. 10, if the abnormal first battery cluster is not adjusted, the charging time of the energy storage system 100 depends on the charging time of the first battery cluster, which is at t ₃ The SOC reaches 80%, and if the charging of the energy storage system 100 is stopped at this time, the second battery cluster is at t ₃ The SOC at the time is much less than 80%, thereby affecting the charge capacity of the energy storage system 100.

It can be understood that, for the energy storage system 100 in the discharge state, the abnormal battery cluster also affects the discharge capacity of the energy storage system 100, so that the electric quantity of at least a part of the battery clusters in the energy storage system 100 cannot be completely released, and the service time of the energy storage system 100 is affected.

Through the adjustment method for the abnormal battery clusters in the energy storage system 100 provided by the embodiment of the application, the charging of the battery cluster 110 with higher capacity in the energy storage system 100 can be slowed down or the charging of the battery cluster 110 with lower capacity can be quickened, or the discharging of the battery cluster 110 with higher capacity can be quickened or the discharging of the battery cluster 110 with lower capacity can be slowed down, so that the capacities of the battery clusters 110 in the energy storage system 100 are balanced, and the charging and discharging performance of the energy storage system 100 is ensured.

In the above embodiment, the control module 150 may adjust the electrical parameter of the first battery cluster in the operating state. Alternatively, the control module 150 may also control the first battery cluster connected in parallel before the other battery clusters, that is, the first battery cluster in a non-operating state.

Optionally, before the first battery cluster is connected in parallel to the other battery clusters of the N battery clusters 110, the control module 150 is further configured to detect an electrical parameter of the first battery cluster to determine whether to connect the first battery cluster in parallel to the other battery clusters.

Specifically, before a first battery cluster is connected in parallel to other battery clusters, the first battery cluster may be separately powered on, and the control module 150 may detect electrical parameters of the first battery cluster, such as voltage, current, and the like, and when the electrical parameters of the first battery cluster exceed a preset range, the first battery cluster is different from the other battery clusters. Considering the regulation capability of the first variable voltage module 120 connected in series to the first battery cluster, even if the first battery cluster is connected in parallel to other battery clusters, the first variable voltage module 120 may not be able to regulate it well, so that the first battery cluster is balanced with other battery clusters.

In view of this, in the embodiment of the present application, before the first battery cluster is connected in parallel to other battery clusters, the control module may further determine whether to connect the first battery cluster in parallel according to the electrical parameter of the first battery cluster, so as to ensure the overall performance of the energy storage system 100. In addition, the regulation capability of the first variable voltage module 120 may be designed within a relatively suitable range without the need for a design that is particularly large to meet the regulation of the first battery cluster that is abnormally severe, and the cost of the first variable voltage module 120 may be relatively low, thereby facilitating the production and manufacture of the energy storage system 100.

Optionally, in some embodiments, the electrical parameter is voltage, and in a case that a voltage difference between the voltage of the first battery cluster and a preset voltage is smaller than or equal to a first preset voltage value, the control module 150 is configured to connect the first battery cluster to other battery clusters in parallel; in the case that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than the first preset voltage value, the control module 150 is configured to not connect the first battery cluster in parallel with the other battery clusters.

In this embodiment, by detecting the voltage of the first battery cluster, it can be determined and controlled whether the first battery cluster can be connected in parallel to other battery clusters more intuitively and quickly.

Optionally, in a case that a voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to a first preset voltage value and greater than or equal to a second preset voltage value, the control module 150 is configured to control a t-th regulating switch connected in series to the first battery cluster to be turned on and other regulating switches to be turned off, and control the t-th first variable voltage module to operate, so that the t-th first variable voltage module regulates the voltage of the first battery cluster to a target voltage range. After the adjustment is completed, the control module 150 is configured to connect the adjusted first battery cluster in parallel to other battery clusters, and control all the adjusting switches connected in series to the first battery cluster to be turned off, and all the bypass switches connected in series to the first battery cluster to be turned on, so that the first battery cluster transmits electric energy to the outside through the bus bar 160.

In this embodiment, in the case where the voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to the first preset voltage value and greater than or equal to the second preset voltage value, an abnormality is generated in the first battery cluster, but the abnormality may be adjusted by any one of the adjustable voltage modules (e.g., the tth adjustable voltage module) connected in series to the first battery cluster. Specifically, the control module 150 may be configured to control the voltage of the tth first variable voltage module, so as to adjust the voltage of the first battery cluster, and after the voltage of the first battery cluster is adjusted to the target voltage range, the first battery cluster may be connected in parallel to the other battery clusters 110 in the N battery clusters 110.

Through the technical scheme of the embodiment, on the basis that the control module 150 detects the voltage of the first battery cluster, the control module 150 may further control the first variable voltage module to adjust the voltage of the first battery cluster, so that the first variable voltage module can be connected in parallel with other battery clusters 110 in the N battery clusters 110, and the capacity and performance of the energy storage system 100 are guaranteed.

Optionally, the first preset voltage value may be related to a voltage regulation range of the tth first variable voltage module, so that the tth first variable voltage module can support voltage regulation of the first battery cluster.

Alternatively, the target voltage range may be related to an average voltage value of the battery clusters that have been connected in parallel with each other among the N battery clusters. For example, the target voltage range may include an average voltage value of the battery clusters that have been connected in parallel with each other among the N battery clusters.

By the technical scheme, the first battery cluster can be ensured to be connected with other battery clusters 110 in the N battery clusters 110 in parallel, and the voltage of each battery cluster 110 is in a balanced state, so that the subsequent normal operation of each battery cluster 110 is facilitated.

In the above application embodiment, the energy storage system 100 provided in the embodiment of the present application is described with reference to fig. 1 to 10, and next, the method for adjusting the energy storage system provided in the embodiment of the present application is described with reference to fig. 11 to 15. It is to be understood that the following method embodiments correspond to the above-described apparatus embodiments, and similar descriptions may be had with reference to the above-described embodiments.

Fig. 11 shows a schematic flow chart of a regulating method 200 of an energy storage system according to an embodiment of the present application. This energy storage system includes: the battery pack comprises N battery clusters, adjusting switch modules, M first variable voltage modules and a second variable voltage module, wherein the N battery clusters are connected in parallel, each battery cluster in the N battery clusters is connected in series with at least one first variable voltage module in the M first variable voltage modules in a one-to-one correspondence mode through at least one adjusting switch in the adjusting switch modules, and the second variable voltage module is used for providing voltage for the M first variable voltage modules, wherein N is a positive integer larger than 1, and M is a positive integer smaller than N.

As shown in fig. 11, the adjustment method 200 may include the following steps.

S210: and controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters, so that the electrical parameters of the N battery clusters are balanced.

Specifically, the adjusting method 200 provided in the embodiment of the present application may be applied to the energy storage system 100 of the embodiment of the application. The main body of execution of the regulating method 200 may be the control module 150 in the energy storage system 100.

In some possible embodiments, the second variable voltage module is connected to a power source, and the first ends of the N battery clusters are connected to the M first variable voltage modules; the second variable voltage module is used for converting the voltage of the power source into a target voltage, and the ratio of the target voltage to the voltage of the first ends of the N battery clusters is greater than 0 and less than or equal to 10.

As an example, the ratio of the target voltage to the voltage of the first terminals of the N battery clusters is greater than or equal to 1 and less than or equal to 5.

In some possible embodiments, the electrical parameter may be SOC or voltage in some possible embodiments. In this case, the step S210 may include: controlling the X regulating switches and the M first variable voltage modules to regulate the SOC of the N battery clusters, so that the SOC of the N battery clusters are balanced; or controlling the X regulating switches and the M first variable voltage modules to regulate the voltages of the N battery clusters, so that the voltages of the N battery clusters are balanced.

Fig. 12 is a schematic flow chart diagram illustrating another energy storage system regulation method 300 provided by the embodiment of the present application.

As shown in fig. 12, the adjustment method 300 may include the following steps.

S310: and detecting the electrical parameters of each battery cluster in the N battery clusters to judge the number of abnormal battery clusters in the N battery clusters.

S320: and under the condition that the number of the abnormal battery clusters is K and K is less than or equal to M, controlling K regulating switches connected in series with the K abnormal battery clusters to be closed and K first variable voltage modules in the M first variable voltage modules to operate simultaneously, so that the K first variable voltage modules regulate the electrical parameters of the K abnormal battery clusters.

S330: and under the condition that the number of the abnormal battery clusters is K and K is greater than M, at least two abnormal battery clusters in the K abnormal battery clusters are connected in series with the same target first variable voltage module in the M first variable voltage modules through at least two regulating switches, the at least two regulating switches are controlled to be sequentially closed, and the target first variable voltage module is controlled to operate, so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters.

Specifically, the executing subjects of the steps S310 to S330 may also be the control module 150 in the energy storage system 100. The control module 150 may detect a battery cluster in the energy storage system 100, and control the adjusting switch and the first variable voltage module to adjust an abnormal battery cluster in the energy storage system 100.

Alternatively, the steps S320 to S330 may be an implementation manner of the step S210 in the embodiment of fig. 11.

Optionally, in the step S330, the control module 150 may control the at least two adjusting switches to be sequentially closed and the target first variable voltage module to operate according to a difference between the electrical parameter of the at least two abnormal battery clusters and a preset threshold, so that the target first variable voltage module sequentially adjusts the electrical parameter of the at least two abnormal battery clusters.

In some possible embodiments, the energy storage system further comprises: y bypass switch and busbar, every battery cluster in N battery cluster is established ties in the busbar through at least one bypass switch in Y bypass switch, and at least one bypass switch is established ties each other, and wherein, Y is less than M N positive integer.

In this case, fig. 13 shows a schematic flow chart of another energy storage system regulation method 400 provided by the embodiment of the present application.

As shown in fig. 13, the adjustment method 400 may include the following steps.

S210: and controlling the M first variable voltage modules and the X regulating switches to regulate the electrical parameters of the N battery clusters, so that the electrical parameters of the N battery clusters are balanced.

S410: and controlling the Y bypass switches to enable the N battery clusters to carry out electric energy transmission with the outside through the bus bar.

Specifically, the executing subject of step S410 may also be the control module 150 in the energy storage system 100. The control module 150 may control Y bypass switches 140 in the energy storage system 100 in addition to X regulating switches 130 in the energy storage system 100.

In other possible embodiments, the ith battery cluster in the N battery clusters is connected in series from the 1 st first variable voltage module to the ith first variable voltage module in the M first variable voltage modules through i regulating switches in a one-to-one correspondence manner, and the ith battery cluster is connected in series to the bus bar through i bypass switches, where i is a positive integer smaller than M; the j-th battery cluster in the N battery clusters is connected in series with the M first variable voltage modules in a one-to-one correspondence mode through the M regulating switches, the j-th battery cluster is connected in series with the bus bar through the M bypass switches, and j is a positive integer larger than or equal to M and smaller than or equal to N.

In some possible embodiments, the N battery clusters include: a first battery cluster, in this case, fig. 14 shows a schematic flow chart of another regulating method 500 of the energy storage system provided by the embodiment of the present application.

As shown in fig. 14, the adjustment method 500 may include the following steps.

S520: and controlling the t-th regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling the t-th bypass switch connected in series with the first battery cluster to be opened and other bypass switches to be closed.

S530: and controlling the tth first variable voltage module connected with the tth adjusting switch in series to adjust the electrical parameter of the first battery cluster, wherein t is a positive integer less than or equal to M.

S540: and all the adjusting switches connected in series with the first battery cluster are controlled to be switched off, and all the bypass switches connected in series with the first battery cluster are controlled to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

Alternatively, the steps S520 to S530 may be an implementation manner of the step S210 in the embodiment shown in fig. 13. The step S540 may be an implementation manner of the step S410 in the embodiment shown in fig. 13.

In some possible embodiments, as shown in fig. 14, before step S520, the adjusting method 500 may further include:

s510: and detecting the electrical parameters of the first battery cluster to determine the first battery cluster as an abnormal battery cluster.

In some possible embodiments, the electrical parameter is SOC, in which case, the step S530 may include: and controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to a preset SOC range.

In some possible embodiments, the controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to the preset SOC range includes: and sending a current instruction to the tth first variable voltage module so that the tth first variable voltage module adjusts the current of the first battery cluster into a target current, and the target current enables the SOC of the first battery cluster to be adjusted to a target SOC in a preset SOC range.

In some possible embodiments, before sending the current command to the tth first variable voltage module, the adjusting method 500 may further include: and determining the target current according to the difference between the SOC of the first battery cluster and the target SOC and the average current of the N battery clusters.

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

Alternatively, k ₁ And n is related to the power regulation capability of the tth first variable voltage module; and/or, k ₁ And N is related to the over-current capability of the N cell clusters.

In other possible embodiments, the target current I' satisfies the following relationship:

Fig. 15 shows a schematic flow chart of another energy storage system regulation method 600 provided in the embodiment of the present application. The conditioning method 600 may be performed before the first battery cluster is connected in parallel with the other battery clusters of the N battery clusters as described above.

As shown in fig. 15, the adjustment method 600 may include the following steps.

S610: detecting an electrical parameter of the first battery cluster;

s620: and judging whether the first battery cluster is connected in parallel with other battery clusters or not according to the electrical parameters of the first battery cluster.

Specifically, the executing main body of the steps S610 to S620 may also be the control module 150 in the energy storage system 100. The control module 150 may detect an electrical parameter of the first battery cluster before being connected in parallel to other battery clusters, in addition to an electrical parameter of the first battery cluster after being connected in parallel to other battery clusters.

In some possible embodiments, the electrical parameter is a voltage, in which case, the step S620 may include: under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to a first preset voltage value, connecting the first battery cluster to other battery clusters in parallel; and under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than the first preset voltage value, the first battery cluster is not connected with other battery clusters in parallel.

In some possible embodiments, the connecting the first battery cluster to the other battery clusters in parallel in the case that the voltage difference between the voltage of the first battery cluster and the preset voltage is less than or equal to the first preset voltage value includes: under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value and larger than or equal to a second preset voltage value, controlling a tth regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling a tth first variable voltage module to operate so that the tth first variable voltage module regulates the voltage of the first battery cluster to a target voltage range; the adjusted first battery cluster is connected in parallel with other battery clusters, all adjusting switches connected in series with the first battery cluster are controlled to be switched off, all bypass switches connected in series with the first battery cluster are controlled to be switched on, and therefore the first battery cluster transmits electric energy with the outside through a bus bar.

In some possible embodiments, the power source of the M first variable voltage modules in the energy storage system is any one of: at least one cell of the N cell clusters; a bus bar of N cell clusters; a power supply battery; or a supply capacitor.

While the application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims

1. An energy storage system, comprising: the battery pack comprises N battery clusters, an adjusting switch module, M first variable voltage modules and a second variable voltage module, wherein N is a positive integer larger than 1, and M is a positive integer smaller than N;

the N battery clusters are mutually connected in parallel, each battery cluster in the N battery clusters is connected in series with at least one first variable voltage module in the M first variable voltage modules in a one-to-one correspondence mode through at least one regulating switch in the regulating switch modules, and the M first variable voltage modules are connected to the second variable voltage module;

the second variable voltage module is used for providing voltage for the M first variable voltage modules, and the M first variable voltage modules and the adjusting switch module are used for adjusting the electrical parameters of the N battery clusters so as to achieve balance among the electrical parameters of the N battery clusters.

2. The energy storage system of claim 1, wherein at least one of the N battery clusters is connected in series with a plurality of first variable voltage modules of the M first variable voltage modules in a one-to-one correspondence via a plurality of regulating switches.

3. The energy storage system of claim 1 or 2, wherein the second variable voltage module is connected to a power source, and the first ends of the N battery clusters are connected to the M first variable voltage modules;

the second variable voltage module is configured to convert a voltage of the power source into a target voltage, and a ratio of the target voltage to a voltage of the first ends of the N battery clusters is greater than 0 and less than or equal to 10.

4. The energy storage system of claim 3, wherein a ratio of the target voltage to the voltage of the first end of the N battery clusters is greater than or equal to 1 and less than or equal to 5.

5. The energy storage system of any one of claims 1 to 4, further comprising: the N battery clusters are connected in parallel with the bus bar;

the second variable voltage module is connected to the bus bar.

6. The energy storage system of any one of claims 1 to 5, wherein the regulating switch module comprises X regulating switches, wherein X is a positive integer less than or equal to N M.

7. The energy storage system of claim 6, wherein the M first variable voltage modules and the X regulating switches are configured to regulate the SOCs of the N battery clusters such that an equalization is achieved between the SOCs of the N battery clusters; alternatively, the first and second electrodes may be,

the M first variable voltage modules and the X adjusting switches are used for adjusting the voltages of the N battery clusters so as to enable the voltages of the N battery clusters to be balanced.

8. The energy storage system of any one of claims 1 to 7, further comprising: a control module;

the control module is used for detecting the electrical parameters of each battery cluster in the N battery clusters so as to judge the number of abnormal battery clusters in the N battery clusters;

and under the condition that the number of the abnormal battery clusters is K and K is less than or equal to M, the control module is used for controlling K first variable voltage modules in the M first variable voltage modules to operate simultaneously, and the K first variable voltage modules are used for adjusting the electrical parameters of the K abnormal battery clusters.

9. The energy storage system according to claim 8, wherein in a case that the number of the abnormal cell clusters is K and K is greater than M, the control module is configured to control a target first variable voltage module of the M first variable voltage modules, which corresponds to at least two abnormal cell clusters of the K abnormal cell clusters, to operate, and the target first variable voltage module is configured to sequentially adjust electrical parameters of the at least two abnormal cell clusters.

10. The energy storage system according to claim 9, wherein the control module is configured to control the target first variable voltage module to sequentially adjust the electrical parameters of the at least two abnormal battery clusters according to a difference between the electrical parameters of the at least two abnormal battery clusters and a preset threshold.

11. The energy storage system of any one of claims 1 to 10, further comprising: bypass switch module and busbar, bypass switch module includes: y bypass switches, wherein Y is a positive integer less than or equal to M N;

each battery cluster in the N battery clusters is connected in series with the bus bar through at least one bypass switch in the Y bypass switches, the at least one bypass switch is connected in series, and the bus bar is used for realizing the transmission of the N battery clusters and external electric energy.

12. The energy storage system of claim 11, wherein each of the N battery clusters is connected in series to the M first variable voltage modules through M regulating switches in a one-to-one correspondence, and wherein each of the N battery clusters is connected in series to the bus bar through M bypass switches.

13. The energy storage system according to claim 11, wherein an ith battery cluster of the N battery clusters is connected in series to 1 st to ith first variable voltage modules of the M first variable voltage modules through i regulating switches in a one-to-one correspondence manner, and the ith battery cluster is connected in series to the bus bar through i bypass switches, i is a positive integer smaller than M;

the j-th battery cluster in the N battery clusters is connected in series with the M first variable voltage modules in a one-to-one correspondence mode through M regulating switches, the j-th battery cluster is connected in series with the bus bar through M bypass switches, and j is a positive integer larger than or equal to M and smaller than or equal to N.

14. The energy storage system of claim 12 or 13, wherein the N battery clusters comprise a first battery cluster;

under the conditions that a tth adjusting switch connected in series with the first battery cluster is closed and other adjusting switches are opened, and a tth bypass switch connected in series with the first battery cluster is opened and other bypass switches are closed, a tth first variable voltage module connected in series with the tth adjusting switch is used for adjusting the electrical parameter of the first battery cluster, wherein t is a positive integer less than or equal to M;

and under the condition that all the adjusting switches connected in series with the first battery cluster are switched off and all the bypass switches connected in series with the first battery cluster are switched on, the first battery cluster transmits electric energy with the outside through the bus bar.

15. The energy storage system of claim 14, further comprising: a control module;

before the tth first variable voltage module is used for adjusting the electrical parameters of the first battery cluster, the control module is used for detecting the electrical parameters of the first battery cluster to determine that the first battery cluster is an abnormal battery cluster;

the control module is used for controlling the t-th regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, the t-th bypass switch connected in series with the first battery cluster to be opened and other bypass switches to be closed, and controlling the t-th first variable voltage module to operate so as to regulate the electrical parameters of the first battery cluster;

after the electrical parameters of the first battery cluster are adjusted to a preset range, the control module is further used for controlling all the adjusting switches connected in series with the first battery cluster to be switched off, and all the bypass switches connected in series with the first battery cluster to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

16. The energy storage system of claim 15, wherein the electrical parameter is SOC;

the control module is used for controlling the operation of the tth first variable voltage module so as to adjust the SOC of the first battery cluster to a preset SOC range.

17. The energy storage system of claim 16, wherein the preset SOC range comprises: the average value or the median value of the SOCs of the N battery clusters, or the preset SOC range includes: the SOC of any one of the N battery clusters except the first battery cluster.

18. The energy storage system of claim 16 or 17, wherein the control module is configured to send a current command to the tth first variable voltage module to cause the tth first variable voltage module to adjust the current of the first battery cluster to a target current, the target current causing the SOC of the first battery cluster to be adjusted to a target SOC in the preset SOC range.

19. The energy storage system of claim 18, wherein the control module is configured to determine the target current based on a difference between the SOC of the first battery cluster and a target SOC and an average current of the N battery clusters.

20. The energy storage system of claim 19, wherein the target current I' satisfies the following relationship:

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

21. The energy storage system of claim 20, wherein k is ₁ And n is related to the power regulation capability of the tth first variable voltage module; and/or, k ₁ And N is related to the over-current capability of the N battery clusters.

22. The energy storage system of claim 19, wherein the target current I' satisfies the following relationship:

i' = k in the case where Δ SOC > 0 and the energy storage system is in a state of charge ₂ *I _ave ，0＜k ₂ ≤1；

Wherein Δ SOC is a difference between the SOC of the first battery cluster and the target SOC, I _ave Is the average current, k, of the N cell clusters ₂ Is a preset coefficient.

23. The energy storage system of any of claims 14-22, further comprising: a control module;

before the first battery cluster is connected in parallel with other battery clusters of the N battery clusters, the control module is further configured to detect an electrical parameter of the first battery cluster to determine whether to connect the first battery cluster in parallel with other battery clusters.

24. The energy storage system of claim 23, wherein the electrical parameter is voltage;

the control module is used for connecting the first battery cluster to other battery clusters in parallel under the condition that the voltage difference between the voltage of the first battery cluster and a preset voltage is smaller than or equal to a first preset voltage value;

and under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than the first preset voltage value, the control module is used for not connecting the first battery cluster in parallel with other battery clusters.

25. The energy storage system according to claim 24, wherein the control module is configured to control a tth regulation switch connected in series to the first battery cluster to be closed and other regulation switches to be opened, and control the tth first variable voltage module to operate so that the tth first variable voltage module regulates the voltage of the first battery cluster to a target voltage range, when a voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value and larger than or equal to a second preset voltage value;

the control module is used for connecting the regulated first battery cluster in parallel with other battery clusters, controlling all regulating switches connected in series with the first battery cluster to be switched off, and controlling all bypass switches connected in series with the first battery cluster to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

26. The energy storage system of claim 25, wherein the first predetermined voltage value is related to a voltage regulation range of the tth first variable voltage module; and/or the presence of a gas in the atmosphere,

the target voltage range is related to an average voltage value of the battery clusters that have been connected in parallel with each other among the N battery clusters.

27. The energy storage system according to any one of claims 1 to 26, wherein the M first variable voltage modules are isolated DC/DC converters or non-isolated DC/DC converters, and/or;

the M first variable voltage modules are used for outputting positive voltage and/or negative voltage.

28. The energy storage system of any of claims 1 to 27, wherein the second variable voltage module is an isolated DC/DC converter or a non-isolated DC/DC converter, and/or;

the second variable voltage module is used for outputting positive voltage and/or negative voltage.

29. A method of regulating an energy storage system, the energy storage system comprising: the adjustment method comprises the following steps of connecting N battery clusters, a regulating switch module, M first variable voltage modules and a second variable voltage module in parallel, connecting each of the N battery clusters to at least one first variable voltage module of the M first variable voltage modules in series in a one-to-one correspondence manner through at least one regulating switch of the regulating switch module, connecting the M first variable voltage modules to the second variable voltage module, and providing voltage to the M first variable voltage modules, wherein N is a positive integer greater than 1, and M is a positive integer smaller than N, and the adjustment method comprises the following steps:

controlling the M first variable voltage modules and the adjusting switch module to adjust the electrical parameters of the N battery clusters, so that the electrical parameters of the N battery clusters are balanced.

30. The method of claim 29, wherein at least one of the N battery clusters is connected in series with a plurality of first variable voltage modules of the M first variable voltage modules through a plurality of regulating switches in a one-to-one correspondence.

31. A method of regulating according to claim 29 or 30, wherein said second variable voltage module is connected to a power source, first terminals of said N battery clusters being connected to said M first variable voltage modules;

the second variable voltage module is used for converting the voltage of the power source into a target voltage, and the ratio of the target voltage to the voltage of the first ends of the N battery clusters is greater than 0 and less than or equal to 10.

32. The method of claim 31, wherein a ratio of the target voltage to a voltage of the first end of the N battery clusters is greater than or equal to 1 and less than or equal to 5.

33. The method of any one of claims 29 to 32, wherein the energy storage system further comprises: the N battery clusters are connected in parallel with the bus bar;

the second variable voltage module is connected to the bus bar.

34. The regulation method according to any one of claims 29 to 33, wherein the regulation switch module comprises X regulation switches, wherein X is a positive integer less than or equal to N X M.

35. The method of adjusting of claim 34, wherein said controlling the M first variable voltage modules and the adjustment switch module to adjust the electrical parameters of the N battery clusters such that a balance is achieved between the electrical parameters of the N battery clusters comprises:

controlling the M first variable voltage modules and the X regulating switches to regulate the SOC of the N battery clusters, so that the SOC of the N battery clusters are balanced; alternatively, the first and second electrodes may be,

controlling the M first variable voltage modules and the X adjusting switches to adjust the voltages of the N battery clusters, so that the voltages of the N battery clusters are balanced.

36. The adjustment method according to any one of claims 29 to 35, characterized in that the adjustment method further comprises: detecting electrical parameters of each battery cluster in the N battery clusters to judge the number of abnormal battery clusters in the N battery clusters;

the controlling the M first variable voltage modules and the regulating switch module to regulate the electrical parameters of the N battery clusters includes:

and under the condition that the number of the abnormal battery clusters is K and K is less than or equal to M, controlling K regulating switches connected in series with the K abnormal battery clusters to be closed and K first variable voltage modules in the M first variable voltage modules to operate simultaneously, so that the K first variable voltage modules regulate the electrical parameters of the K abnormal battery clusters.

37. The method for regulating according to claim 36, wherein said controlling said M first variable voltage modules and said regulating switch module to regulate electrical parameters of said N battery clusters further comprises:

and under the condition that the number of the abnormal battery clusters is K and K is greater than M, at least two abnormal battery clusters in the K abnormal battery clusters are connected in series with the same target first variable voltage module in the M first variable voltage modules through at least two regulating switches, and the at least two regulating switches are controlled to be sequentially closed and the target first variable voltage module is controlled to operate, so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters.

38. The method according to claim 37, wherein the controlling the at least two regulating switches to be sequentially closed and the target first variable voltage module to operate so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters comprises:

and controlling the at least two regulating switches to be sequentially closed and the target first variable voltage module to operate according to the difference value between the electrical parameters of the at least two abnormal battery clusters and a preset threshold value, so that the target first variable voltage module sequentially regulates the electrical parameters of the at least two abnormal battery clusters.

39. The method of conditioning of any of claims 29 to 38, wherein the energy storage system further comprises: bypass switch module and busbar, the bypass switch module includes: each battery cluster in the N battery clusters is connected in series with the bus bar through at least one bypass switch in the Y bypass switches, the at least one bypass switch is connected in series with each other, and Y is a positive integer less than or equal to M N;

the adjusting method further comprises the following steps: and controlling the Y bypass switches to enable the N battery clusters to carry out electric energy transmission with the outside through the bus bar.

40. The method according to claim 39, wherein each of the N battery clusters is connected in series to the M first variable voltage modules through M regulating switches in a one-to-one correspondence manner, and each of the N battery clusters is connected in series to the bus bar through M bypass switches.

41. The method according to claim 39, wherein the ith battery cluster of the N battery clusters is connected in series with the 1 st to the ith first variable voltage modules of the M first variable voltage modules in a one-to-one correspondence manner through i regulating switches, and the ith battery cluster is connected in series with the bus bar through i bypass switches, i is a positive integer less than M;

42. The method of conditioning of claim 40 or 41, wherein the N battery clusters comprise a first battery cluster;

wherein said controlling said M first variable voltage modules and said regulating switch module to regulate electrical parameters of said N battery clusters comprises:

controlling the t-th regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling the t-th bypass switch connected in series with the first battery cluster to be opened and other bypass switches to be closed;

controlling a tth first variable voltage module of the tth adjusting switch in series to adjust the electrical parameter of the first battery cluster, wherein t is a positive integer less than or equal to M;

the controlling the Y bypass switches to enable the N battery clusters to transmit electric energy with the outside through the bus bar comprises:

and controlling all the adjusting switches connected in series with the first battery cluster to be opened and all the bypass switches connected in series with the first battery cluster to be closed so that the first battery cluster transmits electric energy with the outside through the bus bar.

43. The method of adjusting of claim 42, wherein prior to controlling the tth first variable voltage module to adjust the electrical parameter of the first battery cluster, the method of adjusting further comprises:

detecting an electrical parameter of the first battery cluster to determine that the first battery cluster is an abnormal battery cluster.

44. The method of conditioning of claim 43 wherein the electrical parameter is SOC;

wherein the controlling the tth first variable voltage module of the tth series of regulating switches to regulate the electrical parameter of the first battery cluster comprises:

and controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to a preset SOC range.

45. The method of tuning of claim 44, wherein the preset SOC range comprises: the average value or the median value of the SOCs of the N battery clusters, or the preset SOC range includes: the SOC of any one battery cluster except the first battery cluster in the N battery clusters.

46. The method of adjusting of claim 44 or 45, wherein the controlling the operation of the tth first variable voltage module to adjust the SOC of the first battery cluster to a preset SOC range comprises:

sending a current instruction to the tth first variable voltage module to enable the tth first variable voltage module to adjust the current of the first battery cluster to a target current, wherein the target current enables the SOC of the first battery cluster to be adjusted to a target SOC in the preset SOC range.

47. The method of claim 46, wherein prior to said sending a current command to said tth first variable voltage module, said method of adjusting comprises:

and determining the target current according to the difference between the SOC of the first battery cluster and the target SOC and the average current of the N battery clusters.

48. The regulation method of claim 47, wherein the target current I' satisfies the following relationship:

I’＝I _ave +f(ΔSOC)；

f(ΔSOC)＝k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＞0；

f(ΔSOC)＝-k ₁ *((1+ΔSOC) ⁿ -1)，ΔSOC＜0；

49. According toThe method of regulating as claimed in claim 48, wherein k is ₁ And n is related to the power regulation capability of the tth first variable voltage module; and/or, k ₁ And N is related to the over-current capability of the N battery clusters.

50. The regulation method of claim 47, wherein the target current I' satisfies the following relationship:

in the case where Δ SOC > 0 and the regulating method is in the state of charge, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

In the case where Δ SOC < 0 and the regulating method is in the charging state, I' = k ₂ *I _ave ，1＜k ₂ ≤10；

In the case where Δ SOC < 0 and the regulating method is in the discharge state, I' = k ₂ *I _ave ，0＜k ₂ ≤1；

51. The conditioning method in accordance with any of claims 42 to 50, wherein prior to the first battery cluster being connected in parallel to the other of the N battery clusters, the conditioning method further comprises:

detecting an electrical parameter of the first battery cluster;

and judging whether the first battery cluster is connected in parallel with other battery clusters or not according to the electrical parameters of the first battery cluster.

52. The method for adjusting according to claim 51, wherein the electrical parameter is voltage, and wherein the determining whether to connect the first battery cluster in parallel with other battery clusters according to the electrical parameter of the first battery cluster comprises:

under the condition that the voltage difference between the voltage of the first battery cluster and a preset voltage is less than or equal to a first preset voltage value, connecting the first battery cluster to other battery clusters in parallel;

and under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is greater than the first preset voltage value, not connecting the first battery cluster in parallel with other battery clusters.

53. The method for regulating according to claim 52, wherein said connecting the first battery cluster in parallel to the other battery clusters in case that a voltage difference between the voltage of the first battery cluster and a preset voltage is less than or equal to a first preset voltage value comprises:

under the condition that the voltage difference between the voltage of the first battery cluster and the preset voltage is smaller than or equal to a first preset voltage value and larger than or equal to a second preset voltage value, controlling a tth regulating switch connected in series with the first battery cluster to be closed and other regulating switches to be opened, and controlling the tth first variable voltage module to operate so that the tth first variable voltage module regulates the voltage of the first battery cluster to a target voltage range;

and connecting the regulated first battery cluster in parallel with other battery clusters, controlling all regulating switches connected in series with the first battery cluster to be switched off, and controlling all bypass switches connected in series with the first battery cluster to be switched on, so that the first battery cluster transmits electric energy with the outside through the bus bar.

54. The method of claim 53, wherein the first predetermined voltage value is associated with a voltage regulation range of the tth first variable voltage module; and/or the presence of a gas in the gas,

55. The regulation method according to any one of claims 29 to 54, wherein the M first variable voltage modules are isolated DC/DC converters or non-isolated DC/DC converters, and/or;

56. The regulation method according to any one of claims 29 to 55, wherein the second variable voltage module is an isolated DC/DC converter or a non-isolated DC/DC converter, and/or;