Energy storage device and electronic equipment

Abstract

The utility model discloses an energy storage device and electronic equipment. The energy storage device comprises a multi-phase energy storage circuit, each phase energy storage circuit comprises a commutation link, and the commutation link comprises a plurality of cascaded energy storage sub-modules; the current conversion link is connected with at least one first lightning arrester, and the first lightning arrester is connected between different energy storage sub-modules. According to the energy storage device and the electronic equipment provided by the embodiment of the invention, the problem that the energy storage device faces a relatively large failure risk due to lightning impulse can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and particularly to an energy storage device and an electronic device. Background Art

[0002] With the development of energy storage technology, the capacity of energy storage devices has been constantly breaking records. For example, a large-capacity high-voltage chain-type energy storage device composed of cascaded multiple energy storage sub-modules has increasingly prominent technical advantages. By converting the energy stored in the battery to meet the user's power demand, it makes up for the deficiency of new energy power generation.

[0003] Power transmission can be carried out between the energy storage device and the high-voltage power grid. As the voltage level of the energy storage device connected to the power grid increases, the number of energy storage sub-modules in the single-phase energy storage circuit becomes larger, and the overvoltage of the energy storage device to the ground will be higher, resulting in a greater failure risk for the energy storage device. Summary of the Utility Model

[0004] The present application provides an energy storage device and an electronic device, which can solve the problem that the energy storage device faces a greater failure risk caused by lightning strikes.

[0005] In a first aspect, the present application provides an energy storage device, including: a multi-phase energy storage circuit, each phase of the energy storage circuit includes a commutation link, and the commutation link includes a plurality of cascaded energy storage sub-modules; at least one first lightning arrester is connected to the commutation link, and the first lightning arrester is connected between different energy storage sub-modules.

[0006] In the embodiment of the present application, by connecting at least one first lightning arrester to the commutation link, lightning protection can be provided for the commutation link, that is, lightning protection can be provided for the inside of the unit, thereby reducing the overvoltage of the inside of the unit to the ground and limiting the lightning overvoltage level inside the unit, so as to solve the greater failure risk faced by the insulation of the unit.

[0007] In a possible implementation manner of the first aspect, at least one phase of the energy storage circuit includes a plurality of lightning arresters, and the plurality of lightning arresters are connected to different positions of the energy storage circuit.

[0008] In the embodiment of the present application, at least one phase of the energy storage circuit includes a plurality of lightning arresters, and the plurality of lightning arresters are connected to different positions of the energy storage circuit. In this way, lightning arresters can be used for protection at multiple different positions of the energy storage circuit, which can reduce the ground voltage at multiple different positions of the energy storage circuit. Compared with setting a lightning arrester at only one position of the energy storage circuit, the present application can solve the problem that the energy storage device faces a greater failure risk caused by lightning strikes.

[0009] In a possible implementation manner of the first aspect, the commutation link includes n cascaded energy storage sub-modules, the first energy storage sub-module is connected to the neutral point, and the nth energy storage sub-module is connected to the bus;

[0010] At least one first lightning arrester is connected on the path from the m-th energy storage sub-module to the n-th energy storage sub-module, and m is an integer of n / 2.

[0011] From the first energy storage sub-module S 1 to the n-th energy storage sub-module S n , the ground voltage of the energy storage sub-module becomes larger and larger. And the more the number of lightning arresters, the higher the cost. In the embodiment of the present application, at least one first lightning arrester is connected on the path from the m-th energy storage sub-module to the n-th energy storage sub-module, which can better play the lightning protection effect while taking into account the cost.

[0012] In a possible implementation manner of the first aspect, the commutation link includes n cascaded energy storage sub-modules. The first energy storage sub-module is connected to the neutral point, and the n-th energy storage sub-module is connected to the bus;

[0013] p first lightning arresters are connected to the commutation link, where 1 < p < n;

[0014] On the path from the first energy storage sub-module to the n-th energy storage sub-module, the distribution density of the first lightning arresters shows an increasing trend.

[0015] From the first energy storage sub-module S 1 to the n-th energy storage sub-module S n , the ground voltage of the energy storage sub-module becomes larger and larger. And the more the number of lightning arresters, the higher the cost. In the embodiment of the present application, on the path from the first energy storage sub-module S 1 to the n-th energy storage sub-module S n , the distribution density of the first lightning arresters shows an increasing trend. In this way, it is possible to match the voltage trend of multiple energy storage sub-modules to distribute multiple first lightning arresters, which can better play the lightning protection effect.

[0016] In a possible implementation manner of the first aspect, each phase energy storage circuit further includes a reactor and a bus, and the commutation link is connected to the bus through the reactor;

[0017] A second lightning arrester is connected on the connection path between the reactor and the commutation link.

[0018] During lightning intrusion, the reactor is prone to inter-pole breakdown. In the embodiment of the present application, by setting the second lightning arrester to be connected to the reactor, lightning protection can be provided for the reactor, thereby reducing the risk of the reactor being broken down during lightning intrusion.

[0019] In a possible implementation manner of the first aspect, the energy storage circuit further includes a third lightning arrester, and the third lightning arrester is connected in parallel with the reactor.

[0020] When lightning invades, the voltage difference across the reactor is relatively large. A third lightning arrester 23 is provided in parallel with the reactor 13, and part of the current is introduced into the third lightning arrester, so as to better avoid the reactor being damaged.

[0021] In a possible implementation manner of the first aspect, the commutation link is connected to the neutral point, and a fourth lightning arrester is connected to the neutral point. In this way, lightning protection can also be carried out at the neutral point position.

[0022] In a possible implementation manner of the first aspect, each phase energy storage circuit is connected to the neutral point, and the number of the fourth lightning arresters is 1. By setting one fourth lightning arrester in this way, it can achieve lightning protection for multiple phase energy storage circuits and can reduce costs.

[0023] In a possible implementation manner of the first aspect, the protection ability of the fourth lightning arrester is less than that of the lightning arresters connected at other positions in the energy storage circuit. The voltage at the neutral point is relatively small compared to other positions. By selecting a relatively small protection ability for the lightning arrester connected to the neutral point, the cost of the energy storage device can be reduced.

[0024] In a possible implementation manner of the first aspect, each phase energy storage circuit further includes a bus, and the commutation link is connected to the bus; a fifth lightning arrester is connected to the bus. In this way, lightning protection can also be carried out at the bus position.

[0025] Based on the same inventive concept, in the second aspect, an embodiment of the present application further provides an electronic device, including the energy storage device described in the first aspect or any one of the embodiments of the first aspect.

[0026] Based on the same inventive concept, in the second aspect, an embodiment of the present application further provides an electrical device, which includes a battery and a charging circuit as described in any one of the embodiments of the first aspect.

[0027] The above description is only an overview of the technical solutions of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application are specifically given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The features, advantages and technical effects of the exemplary embodiments of the present application will be described below with reference to the drawings.

[0029] Figure 1 It is a schematic structural diagram of an energy storage device according to an embodiment of the present application;

[0030] Figure 2 It is a schematic structural diagram of an energy storage sub-module in an energy storage device according to an embodiment of the present application;

[0031] Figure 3Schematic diagram of the structure of another energy storage device according to an embodiment of the present application;

[0032] Figure 4 Schematic diagram of the structure of yet another energy storage device according to an embodiment of the present application;

[0033] Figure 5 Schematic diagram of the structure of yet another energy storage device according to an embodiment of the present application;

[0034] Figure 6 Schematic diagram of the structure of yet another energy storage device according to an embodiment of the present application;

[0035] Figure 7 Schematic diagram of the structure of yet another energy storage device according to an embodiment of the present application;

[0036] Figure 8 Schematic diagram of the structure of yet another energy storage device according to an embodiment of the present application;

[0037] Figure 9 A simulation diagram of the lightning protection effect of different lightning protection schemes.

[0038] In the drawings, the drawings are not necessarily drawn to actual scale.

[0039] In the drawings: 10, energy storage circuit; 10A, phase A energy storage circuit; 10B, phase B energy storage circuit; 10C, phase C energy storage circuit;

[0040] 11, commutation link; 111, energy storage sub-module; 1111, battery unit; 1112, control circuit;

[0041] S1~Sn, the 1st energy storage sub-module ~ the nth energy storage sub-module;

[0042] 12, busbar; 12A, phase A busbar; 12B, phase B busbar; 12C, phase C busbar;

[0043] 13, reactor;

[0044] 20, lightning arrester;

[0045] 21, first lightning arrester; 22, second lightning arrester; 23, third lightning arrester; 24, fourth lightning arrester; 25, fifth lightning arrester. Detailed implementation manners

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the scope of protection of this application.

[0047] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0048] The terms "first", "second", etc. in the specification and claims of this application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0049] In the description of the embodiments of this application, the term "and / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0050] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0051] Power transmission can be carried out between the energy storage device and the high-voltage power grid. As the voltage level of the energy storage device connected to the power grid increases, the number of energy storage sub-modules in the single-phase energy storage circuit becomes larger. For example, when the energy storage device is connected to a 35 kV power grid, the number of energy storage sub-modules in the single-phase energy storage circuit can be as many as dozens, and the overvoltage of the energy storage device to the ground will be higher, resulting in a greater risk of failure for the energy storage device.

[0052] However, the lightning protection schemes in the related technologies cannot effectively limit the lightning overvoltage level of the energy storage device, and the insulation of the unit faces a greater risk of failure.

[0053] To solve the above technical problems, embodiments of the present application provide an energy storage device and an electronic device. The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0054] As Figure 1 shown, the energy storage device provided by the embodiments of the present application includes a multi-phase energy storage circuit 10. Each phase of the energy storage circuit 10 includes a commutation link 11. The commutation link 11 includes a plurality of cascaded energy storage sub-modules 111; at least one lightning arrester 20 can be connected to the commutation link 11, and the first lightning arrester is connected between different energy storage sub-modules. For ease of distinction, the lightning arrester 20 connected to the commutation link 11 is denoted as the first lightning arrester 21. For example, the commutation link includes n energy storage sub-modules, which are the 1st to the nth energy storage sub-modules respectively. The connection path between the (n - 1)th energy storage sub-module S n-1 and the nth energy storage sub-module S n is connected with a first lightning arrester 21, and the other end of the first lightning arrester 21 is grounded.

[0055] Exemplarily, the energy storage device may include an Electrochemical Energy Storage (EES) system. EES technology can store electrical energy in a battery using a reversible chemical reaction and release energy through a reverse reaction. EES technology can reduce environmental pollution and is sustainable. Of course, in other examples, the energy storage device can also be of other types. For example, the energy storage device is an air energy storage device, a gravity energy storage device, a flywheel energy storage device, etc.

[0056] Exemplarily, the energy storage device includes three-phase energy storage circuits 10 of ABC, namely the A-phase energy storage circuit 10A, the B-phase energy storage circuit 10B, and the C-phase energy storage circuit 10C. The number of energy storage sub-modules 111 in each phase of the energy storage circuit can be the same.

[0057] Of course, in other examples, the energy storage device can also include a two-phase energy storage circuit, which is not limited in the embodiments of the present application.

[0058] The cascading of multiple energy storage sub-modules 111 in the commutation link 11 may include: the electrodes of multiple energy storage sub-modules 111 are connected in sequence.

[0059] For example, as Figure 1 shown, the number of energy storage sub-modules 111 in the phase energy storage circuit is n, and the n energy storage sub-modules are S 1 ~S n . The energy storage sub-module 111 includes a first pole and a second pole. Taking the (i - 1)th energy storage sub-module S i-1 the ith energy storage sub-module S i and the (i + 1)th energy storage sub-module S i+1 as an example, the ith energy storage sub-module S iThe first pole of is connected to the (i - 1)-th energy storage sub-module S i-1 The second pole of, and the second pole of the i-th energy storage sub-module S i is connected to the first pole of the (i + 1)-th energy storage sub-module S i+1 where i is any one of 2 to n - 1. The first pole of the first energy storage sub-module S 1 is connected to the neutral point N, and the second pole of the n-th energy storage sub-module S n is connected to the bus 12.

[0060] Exemplarily, each phase commutation link 11 can be connected to the bus 12 through a reactor 13 respectively.

[0061] As an example, as Figure 2 shown, the energy storage sub-module 111 includes a battery unit 1111 and a control circuit 1112. The battery unit 1111 includes one or more batteries. The multiple batteries can be connected in series, in parallel, or in a series-parallel combination, for example. The battery unit 1111 is connected to the control circuit 1112. The control circuit 1112 includes multiple switches. By controlling the states of the switches, the control circuit 1112 can control the charging or discharging of the battery unit 1111. It should be noted that Figure 2 the structure shown is only an example and is not used to limit the present application.

[0062] Exemplarily, one end of at least one lightning arrester 20 is connected to the energy storage circuit, and the other end of the lightning arrester 20 can be grounded. When the energy storage device is struck by lightning or subjected to other external voltage impacts, the lightning arrester 20 will conduct the overvoltage to the ground to protect the energy storage device from damage.

[0063] As an example, the lightning arrester 20 can include a Metal Oxide Surge Arrester (MOA). Of course, in other examples, the lightning arrester 20 can also be other types of lightning arresters.

[0064] In the embodiments of the present application, by connecting at least one first lightning arrester 21 on the commutation link 11, even if lightning invades the commutation link, due to the provision of the first lightning arrester 21, lightning protection can be provided for the commutation link 11, that is, lightning protection can be provided for the inside of the unit, thereby reducing the overvoltage to the ground inside the unit and limiting the lightning overvoltage level inside the unit, thus solving the relatively large failure risk faced by the insulation of the unit.

[0065] In some embodiments, as Figure 3 shown, at least one phase of the energy storage circuit 10 includes multiple lightning arresters 20, and the multiple lightning arresters 20 are connected at different positions of the energy storage circuit.

[0066] Exemplarily, different positions of the energy storage circuit include: positions between different modules in the energy storage circuit. The modules include energy storage sub-modules, busbars, reactors, etc. Multiple positions on the connection path between two modules are the same position. For example, multiple positions on the connection path between the second energy storage sub-module S 2 and the third energy storage sub-module S 3 are the same position, and multiple positions on the connection path between the second energy storage sub-module S 2 and the third energy storage sub-module S 3 and the connection path between the (n - 1)-th energy storage sub-module S n-1 and the n-th energy storage sub-module S n are different positions of the energy storage circuit.

[0067] The energy storage circuit 10 includes two or more lightning arresters 20. Taking the energy storage circuit 10 including two lightning arresters 20 as an example, as an example, as Figure 1 shown, one of the lightning arresters 20 can be connected to the commutation link 11, and the other lightning arrester is connected to the busbar. It should be noted that Figure 1 taking one lightning arrester 20 connected to the connection path between the (n - 1)-th energy storage sub-module S n-1 and the n-th energy storage sub-module S n and one lightning arrester connected to the busbar 12 for illustration, this does not limit the present application. For example, as another example, one of the lightning arresters can be connected to the commutation link, and the other lightning arrester is connected to the neutral point. As yet another example, one of the lightning arresters is connected to the busbar, and the other lightning arrester is connected to the reactor. In other examples, the connection positions of multiple lightning arresters can be set in other ways, which will not be listed one by one here.

[0068] According to the energy storage device provided by the embodiments of the present application, at least one phase of the energy storage circuit includes multiple lightning arresters, and the multiple lightning arresters are connected to different positions of the energy storage circuit. In this way, lightning arresters can be used for protection at multiple different positions of the energy storage circuit, and the ground voltage at multiple different positions of the energy storage circuit can be reduced. Compared with only setting a lightning arrester at one position of the energy storage circuit, the present application can solve the problem that the energy storage device faces a greater failure risk caused by lightning strikes.

[0069] It can be understood that at least two lightning arresters are connected to the single-phase energy storage circuit. When one lightning arrester can be connected to the commutation link 11, at least one lightning arrester is connected to other positions of the single-phase energy storage circuit. For example, at least one lightning arrester is connected to the busbar, and / or at least one lightning arrester is connected to the reactor, and / or at least one lightning arrester is connected to the neutral point.

[0070] In some embodiments, as Figure 3As shown, the commutation link 11 includes n energy storage sub-modules 111 connected in cascade. The first energy storage sub-module S 1 is connected to the neutral point N, and the nth energy storage sub-module S n is connected to the bus 12. At least one first lightning arrester 21 is connected on the path from the mth energy storage sub-module to the nth energy storage sub-module, where m is an integer of n / 2.

[0071] For example, when n = 30 or n = 31, m is 15. In this case, at least one first lightning arrester 21 is connected on the path from the 15th energy storage sub-module to the nth energy storage sub-module.

[0072] As an example, as Figure 3 shown, 2 first lightning arresters 21 can be connected on the path from the mth energy storage sub-module to the nth energy storage sub-module. For example, when m = 15, one first lightning arrester 21 is connected on the path from the 15th energy storage sub-module S 15 to the 16th energy storage sub-module S 16 , and one first lightning arrester 21 is connected on the path from the (n - 1)th energy storage sub-module S n- to the nth energy storage sub-module S n .

[0073] When at least one first lightning arrester 21 is connected on the path from the mth energy storage sub-module to the nth energy storage sub-module, a lightning arrester may or may not be connected on the path from the first energy storage sub-module to the mth energy storage sub-module.

[0074] From the first energy storage sub-module S 1 to the nth energy storage sub-module S n , the ground voltage of the energy storage sub-module becomes larger and larger. And the more the number of lightning arresters, the higher the cost. In the embodiment of the present application, at least one first lightning arrester 21 is connected on the path from the mth energy storage sub-module to the nth energy storage sub-module, which can better play the lightning protection effect while taking into account the cost.

[0075] In some embodiments, the commutation link 11 includes n energy storage sub-modules 111 connected in cascade. The first energy storage sub-module S 1 is connected to the neutral point N, and the nth energy storage sub-module S n is connected to the bus 12. p first lightning arresters 21 are connected on the commutation link, where 1 < p < n. On the path from the first energy storage sub-module S 1 to the nth energy storage sub-module S n , the distribution density of the first lightning arrester 21 shows an increasing trend. In other words, multiple first lightning arresters 21 are connected on the commutation link, and the closer to the nth energy storage sub-module S n, the distribution of the first lightning arrester 21 is denser. Or rather, the closer it is to the nth energy storage sub-module S n , the fewer the number of energy storage sub-modules distributed between two adjacent first lightning arresters 21.

[0076] As an example, n = 30. As Figure 4 shown, the 7th energy storage sub-module, the 11th energy storage sub-module, the 19th energy storage sub-module, and the 28th energy storage sub-module are each connected to a first lightning arrester 21. Taking the example that the ith energy storage sub-module is connected to a first lightning arrester, it can be: a first lightning arrester is connected on the connection path between the ith energy storage sub-module and the (i + 1)th energy storage sub-module, or a first lightning arrester is connected on the connection path between the ith energy storage sub-module and the (i - 1)th energy storage sub-module, for example, i is any one of 7, 11, 19, and 28.

[0077] From the 1st energy storage sub-module S 1 to the nth energy storage sub-module S n , the ground voltage of the energy storage sub-module is getting larger and larger. And the more the number of lightning arresters, the higher the cost. In the embodiment of the present application, on the path from the 1st energy storage sub-module S 1 to the nth energy storage sub-module S n , the distribution density of the first lightning arrester 21 shows an increasing trend. In this way, multiple first lightning arresters can be distributed to match the voltage trend of multiple energy storage sub-modules, and the lightning protection effect can be better achieved.

[0078] Of course, in other examples, for example, without considering the cost, lightning arresters can be connected between each energy storage sub-module, so as to ensure that the lightning protection effect can be achieved for each energy storage sub-module.

[0079] In some embodiments, as Figure 5 shown, each phase energy storage circuit further includes a reactor 13 and a bus 12. The commutation link 11 is connected to the bus 12 through the reactor 13. The bus 12 is connected to the power grid. A second lightning arrester 22 is connected on the connection path between the reactor 13 and the commutation link 11. The other end of the second lightning arrester 22 can be grounded. The reactor 13 is connected to the nth energy storage sub-module S n in the commutation link 11. The connection path between the reactor 13 and the commutation link 11 is the connection path between the reactor 13 and the nth energy storage sub-module S n in the commutation link 11.

[0080] When lightning invades, the reactor is prone to inter-pole breakdown. In the embodiment of the present application, by setting the second lightning arrester to be connected to the reactor, lightning protection can be provided for the reactor, thereby reducing the risk of the reactor being broken down when lightning invades.

[0081] It is understandable that at least two lightning arresters are connected to the single-phase energy storage circuit. When a second lightning arrester 22 is connected on the connection path between the reactor 13 and the commutation link 11, at least one lightning arrester is connected at other positions of the single-phase energy storage circuit. For example, one lightning arrester is connected on the commutation link 11, and / or at least one lightning arrester is connected to the bus, and / or at least one lightning arrester is connected to the neutral point.

[0082] In some embodiments, as Figure 6 shown, the energy storage circuit further includes a third lightning arrester 23, and the third lightning arrester 23 is connected in parallel with the reactor 13.

[0083] When lightning invades, the voltage difference across the reactor is relatively large. By setting the third lightning arrester 23 to be connected in parallel with the reactor 13, part of the current is introduced into the third lightning arrester, so as to better avoid the reactor from being damaged.

[0084] It is understandable that both the second lightning arrester 22 and the third lightning arrester 23 provide lightning protection for the reactor 13, and the second lightning arrester 22 and the third lightning arrester 23 can be understood as lightning arresters at the same position. When the second lightning arrester 22 and the third lightning arrester 23 are provided, at least one lightning arrester is connected at other positions of the single-phase energy storage circuit. For example, one lightning arrester is connected on the commutation link 11, and / or at least one lightning arrester is connected to the bus, and / or at least one lightning arrester is connected to the neutral point.

[0085] Exemplarily, the reactor in the present application includes an inductor.

[0086] It should be noted that Figures 3 to 6 only the structural schematic diagram of the single-phase energy storage circuit in the energy storage device is shown, and the circuit structure of any phase in the multi-phase energy storage circuit of the energy storage device can be Figures 3 to 6 the structure shown in any of the drawings. For example, the circuit structures of the multi-phase energy storage circuits of the energy storage device are the same, and are all Figures 3 to 6 the structure shown in any of the drawings.

[0087] In some embodiments, as Figure 7 shown, the commutation link 11 is connected to the neutral point N, and a fourth lightning arrester 24 is connected to the neutral point N. In this way, lightning protection can also be carried out at the neutral point position.

[0088] In some embodiments, please continue to refer to Figure 7 , each phase energy storage circuit 10 is connected to the neutral point N, and the number of the fourth lightning arresters 24 is 1. For example, the A-phase energy storage circuit 10A, the B-phase energy storage circuit 10B, and the C-phase energy storage circuit 10C are all connected to the neutral point N, and the fourth lightning arrester 24 is shared by the A-phase energy storage circuit 10A, the B-phase energy storage circuit 10B, and the C-phase energy storage circuit 10C. By setting one fourth lightning arrester in this way, lightning protection can be achieved for the multi-phase energy storage circuit, and the cost can be reduced.

[0089] In some embodiments, as Figure 8 shown, each phase energy storage circuit further includes a busbar 12, and the commutation link 11 is connected to the busbar 12. Specifically, the commutation link 11 is connected to the busbar 12 through a reactor 13. A fifth lightning arrester 25 is connected to the busbar 12. In this way, lightning protection can also be carried out at the busbar position.

[0090] In some embodiments, the protection ability of the fourth lightning arrester 24 connected to the neutral point N is less than that of the lightning arresters connected at other positions in the energy storage circuit. For example, in the above embodiments, the first lightning arrester 21, the second lightning arrester 22, the third lightning arrester 23, the fourth lightning arrester 24, and the fifth lightning arrester 25 are introduced. Among these lightning arresters, the protection ability of the fourth lightning arrester 24 is the smallest.

[0091] The voltage of the neutral point is relatively small compared to other positions. Selecting a relatively small protection ability for the lightning arrester connected to the neutral point can reduce the cost of the energy storage device.

[0092] Exemplarily, the protection ability of the lightning arrester can depend on its rated voltage. For example, the larger the rated voltage of the lightning arrester, the greater the protection ability of the lightning arrester. For the first lightning arrester 21, the second lightning arrester 22, the third lightning arrester 23, the fourth lightning arrester 24, and the fifth lightning arrester 25, the rated voltage of the fourth lightning arrester 24 can be the smallest.

[0093] As an example, the protection abilities of the first lightning arrester 21, the second lightning arrester 22, the third lightning arrester 23, and the fifth lightning arrester 25 can be the same.

[0094] Of course, in other examples, lightning arresters with different protection abilities can be selected according to the lightning protection requirements of each position.

[0095] As an alternative embodiment, as Figure 8 shown, the energy storage device includes a phase A energy storage circuit 10A, a phase B energy storage circuit 10B, and a phase C energy storage circuit 10C. The number of energy storage sub-modules 111 in each phase energy storage circuit is the same. The relative connection positions of the lightning arresters in the phase A energy storage circuit 10A, the phase B energy storage circuit 10B, and the phase C energy storage circuit 10C are the same.

[0096] Figure 8In the figure, a fifth lightning arrester 25 is connected to each of the phase A busbar 12A, phase B busbar 12B, and phase C busbar 12C; in each of the phase A energy storage circuit 10A, phase B energy storage circuit 10B, and phase C energy storage circuit 10C, a first lightning arrester is connected to the AC output line of the second energy storage sub-module to the (n - 1)-th energy storage sub-module. These first lightning arresters are respectively labeled as MOA-Z1 to MOA-Zx, where 1 < x < n - 2; in each of the phase A energy storage circuit 10A, phase B energy storage circuit 10B, and phase C energy storage circuit 10C, a third lightning arrester 23 is connected to the connection path between the reactor 13 and the n-th energy storage sub-module; the neutral point N is connected to a fourth lightning arrester 24.

[0097] The inventor of the present application also conducted simulation verification on the lightning protection effects of different lightning protection schemes, such as Figure 9 shown in the figure, the commutation link includes 30 energy storage sub-modules, and the numbers of the energy storage sub-modules are 0 to 29. Among them, the energy storage sub-module numbered 0 is connected to the neutral point, and the energy storage sub-module numbered 29 is connected to the busbar. Figure 9 In the figure, the vertical coordinate represents the overvoltage amplitude (kV), the horizontal coordinate represents the number of the energy storage sub-module, curve 1 represents the overvoltage amplitude of each energy storage sub-module under lightning protection scheme 1, curve 2 represents the overvoltage amplitude of each energy storage sub-module under lightning protection scheme 2, and curve 3 represents the overvoltage amplitude of each energy storage sub-module under lightning protection scheme 3. In lightning protection scheme 1, a lightning arrester is respectively connected to the busbar and the energy storage sub-module numbered 29. In lightning protection scheme 2, a lightning arrester is respectively connected to the busbar, the energy storage sub-module numbered 29, and the energy storage sub-module numbered 0. In lightning protection scheme 3, a lightning arrester is respectively connected to the busbar, the energy storage sub-module numbered 0, the energy storage sub-module numbered 3, the energy storage sub-module numbered 11, the energy storage sub-module numbered 19, and the energy storage sub-module numbered 27. It can be seen from Figure 9 this that the lightning protection effect of lightning protection scheme 3 is the best.

[0098] Exemplarily, when the scale of the energy storage station is large, the lead wire is long, and there is a steep wave or flashover of the grid-connected reactor, the overvoltage will exceed the protection level of a single lightning arrester. If the basic lightning protection scheme is not sufficient to protect the insulation effect of the energy storage unit, a deep lightning protection scheme can be adopted to limit the overvoltage of all nodes inside the energy storage unit within the protection level of the lightning arrester, which can ensure the safety of the insulation of the energy storage unit. Among them, the basic lightning protection scheme may include connecting lightning arresters to the busbar, the neutral point, and the connection path between the reactor and the commutation link respectively. The deep lightning protection scheme may include connecting lightning arresters to the busbar, the neutral point, and the connection path between the reactor and the commutation link respectively, and at least one lightning arrester is connected to the commutation link.

[0099] It can be understood that the deep lightning protection scheme penetrates the lightning protection measures into the interior of the unit (i.e., within the commutation link), which can suppress the lightning wave process inside the unit and clamp the maximum lightning strike overvoltage level between the poles and the ground of each energy storage sub-module of the unit.

[0100] The inventors of the present application also conducted simulation verification on the deep lightning protection solution. Through verification, it is obtained that regardless of whether the energy storage unit is in the operating state or in the hot standby state, under the deep lightning protection solution, for lightning strikes from the grid side, including various scenarios such as inter-pole flashover of the grid-connected reactor and steep wave intrusion caused by lightning strikes, the lightning overvoltages at the high and low voltage ends of the AC side of each energy storage sub-module of the energy storage unit and between the positive and negative poles of the battery side to the ground can be limited below the protection level of the lightning arrester, ensuring the insulation safety of the energy storage unit.

[0101] Based on the same inventive concept, the present application also provides an electronic device. The electronic device includes the energy storage device in any of the above embodiments. It can be understood that the electronic device has the beneficial effects of the energy storage device provided in the embodiments of the present application. For specific details, reference can be made to the specific descriptions of the energy storage device in the above embodiments, which will not be elaborated herein.

[0102] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0103] Although the present application has been described with reference to the preferred embodiments, various improvements can be made to it and its components can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An energy storage device, characterized in that: include: A multi-phase energy storage circuit, each phase of the energy storage circuit comprises a commutation link, and the commutation link comprises a plurality of cascaded energy storage submodules; At least one first lightning arrester is connected to the commutation link, and the first lightning arrester is connected between different energy storage submodules.

2. The energy storage device according to claim 1, characterized in that: At least one phase of the energy storage circuit includes a plurality of lightning arresters, and the plurality of lightning arresters are connected to different positions of the energy storage circuit.

3. The energy storage device according to claim 1 or 2, characterized in that: The commutation link comprises n cascaded energy storage submodules, the first energy storage submodule is connected to the neutral point, and the nth energy storage submodule is connected to the busbar; At least one of the first lightning arresters is connected on the path from the mth energy storage submodule to the nth energy storage submodule, where m is an integer of n / 2.

4. The energy storage device according to claim 1 or 2, characterized in that: The commutation link comprises n cascaded energy storage submodules, the first energy storage submodule is connected to the neutral point, and the nth energy storage submodule is connected to the busbar; The commutation link is connected to p first lightning arresters, 1<p<n; On the path from the first energy storage submodule to the nth energy storage submodule, the distribution density of the first lightning arresters tends to increase.

5. The energy storage device according to claim 1 or 2, characterized in that: The energy storage circuit of each phase further includes a reactor and a busbar, and the commutation link is connected to the busbar through the reactor; A second lightning arrester is connected to the connection path between the reactor and the commutation link.

6. The energy storage device according to claim 5, characterized in that: The energy storage circuit further includes a third lightning arrester, and the third lightning arrester is connected in parallel with the reactor.

7. The energy storage device according to claim 1 or 2, characterized in that: The commutation link is connected to a neutral point, and the neutral point is connected to a fourth lightning arrester.

8. The energy storage device according to claim 7, characterized in that: The energy storage circuit of each phase is connected to the neutral point, and the number of the fourth lightning arrester is 1.

9. The energy storage device according to claim 7, characterized in that: The protection capability of the fourth lightning arrester is smaller than the protection capability of lightning arresters connected to other positions in the energy storage circuit.

10. The energy storage device according to claim 1 or 2, characterized in that: The energy storage circuit of each phase further includes a busbar, and the commutation link is connected to the busbar; The busbar is connected with a fifth lightning arrester.

11. An electronic device, characterized in that: Comprising the energy storage device as claimed in any one of claims 1-10.

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