Hierarchical fusing matching method of energy storage system

Abstract

The invention provides a hierarchical fusing matching method of an energy storage system. The method comprises the following steps: acquiring expected short-circuit time of the energy storage system; when the expected short-circuit time is less than the preset time, controlling the pre-arc I2t of the third fuse to be greater than the fusing I2t of the second fuse, and controlling the pre-arc I2t of the second fuse to be greater than the fusing I2t of the first fuse; and when the expected short-circuit time is not less than the preset time, controlling the fusing time of the third fuse to be greater than the fusing time of the second fuse, and controlling the fusing time of the second fuse to be greater than the fusing time of the first fuse. According to the hierarchical fusing matching method of the energy storage system, hierarchical fusing protection of the first fuse, the second fuse and the third fuse can be more obvious, and the matching performance among the first fuse, the second fuse and the third fuse is better, so that the overall protection effect of the energy storage system is effectively improved; and safe and efficient operation of the energy storage system is ensured.

Description

Technical Field

[0001] The present disclosure relates to the technical field of fuses, and in particular to a hierarchical fuse matching method for an energy storage system. Background Art

[0002] In energy storage systems, fuses are a key protective device whose main function is to protect circuits and equipment from damage caused by overcurrent and short-circuit faults.

[0003] At present, each level in the energy storage system is equipped with fuses. Although each fuse can protect the protected devices at its level respectively, due to the poor matching between the fuses at each level, the overall protection effect of the energy storage system is poor, which seriously affects the safe and efficient operation of the energy storage system. Summary of the invention

[0004] The present disclosure aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, the purpose of the present disclosure is to provide a hierarchical fuse matching method for an energy storage system.

[0006] To achieve the above object, the present disclosure provides a hierarchical fuse matching method for an energy storage system, wherein the energy storage system comprises: a primary system and a first fuse for short-circuit protection of the primary system, the primary system comprises: a plurality of secondary systems and a second fuse for short-circuit protection of the secondary system, the secondary system comprises: a plurality of tertiary systems and a third fuse for short-circuit protection of the tertiary systems, wherein the method comprises: obtaining an expected short-circuit time of the energy storage system; when the expected short-circuit time is less than a preset time, controlling the pre-arc I of the third fuse 2 t is greater than the melting point of the second fuse 2 t, and the pre-arcing I 2 t is greater than the melting point of the first fuse 2 t; when the expected short-circuit time is not less than the preset time, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is greater than the fusing time of the first fuse.

[0007] Optionally, the method also includes: obtaining a first tolerance time of the protected device in the primary system, and controlling the blowing time of the first fuse to be less than the first tolerance time; and / or, obtaining a second tolerance time of the protected device in the secondary system, and controlling the blowing time of the second fuse to be less than the second tolerance time; and / or, obtaining a third tolerance time of the protected device in the tertiary system, and controlling the blowing time of the third fuse to be less than the third tolerance time.

[0008] Optionally, the method also includes: controlling the blowing time of the first fuse to be less than one half of the first tolerance time; and / or controlling the blowing time of the second fuse to be less than one half of the second tolerance time; and / or controlling the blowing time of the third fuse to be less than one half of the third tolerance time.

[0009] Optionally, the method also includes: determining a derating factor; obtaining the rated current of the first fuse based on the peak current of the primary system and the derating factor; obtaining the rated current of the second fuse based on the peak current of the secondary system and the derating factor; obtaining the rated current of the third fuse based on the peak current of the tertiary system and the derating factor.

[0010] Optionally, the rated current of the first fuse is equal to the peak current of the primary system divided by the derating factor; and / or, the rated current of the second fuse is equal to the peak current of the secondary system divided by the derating factor; and / or, the rated current of the third fuse is equal to the peak current of the tertiary system divided by the derating factor.

[0011] Optionally, the derating factor is equal to the product of the ambient temperature derating factor, the connecting device heat conduction derating factor, the air cooling derating factor, the frequency derating factor and the altitude derating factor.

[0012] Optionally, the derating factor is not less than 0.5.

[0013] Optionally, the derating factor is not greater than 0.8.

[0014] Optionally, the preset time is 0.1s; wherein, when the expected short-circuit time is less than 0.1s, the pre-arc I of the third fuse is controlled. 2 t is greater than the melting point of the second fuse 2 t, and the pre-arcing I 2 t is greater than the melting point of the first fuse 2 t; when the expected short-circuit time is not less than 0.1s, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is greater than the fusing time of the first fuse.

[0015] Optionally, the primary system is a battery stack, and the first fuse is connected in series in the DC combiner box of the battery stack and is used for short-circuit protection of the battery stack; the secondary system is a battery cluster, and the second fuse is connected in series in the high-voltage box of the battery cluster and is used for short-circuit protection of the battery cluster; the tertiary system is a battery pack, and the third fuse is connected in series in the battery pack and is used for short-circuit protection of the battery pack; wherein, the battery stack comprises: a plurality of battery clusters connected in series and / or in parallel, and the battery cluster comprises: a plurality of battery packs connected in series and / or in parallel, and the battery pack comprises: a plurality of single cells connected in series and / or in parallel.

[0016] The technical solution provided by the present disclosure may have the following beneficial effects:

[0017] When the expected short-circuit time is less than the preset time, the overall short-circuit duration is short, and it can be considered that the short-circuit energy is fully used to melt the fuse, so I 2 t is matched, specifically: the arc pre-arc I 2 t is greater than the second fuse I 2 t, and the pre-arc I 2 t is greater than the first fuse I 2 t; When the expected short-circuit time is not less than the preset time, the overall short-circuit duration is long, the fuse will dissipate heat, and the short-circuit energy cannot be fully used to melt the fuse, so the IT curve is used for matching, specifically: the melting time of the third fuse is greater than the melting time of the second fuse, and the melting time of the second fuse is greater than the melting time of the first fuse. Therefore, by comparing the expected short-circuit time with the preset time, and using I 2 t is matched. When the short circuit lasts for a long time, the IT curve is used for matching, which can make the graded fuse protection of the first fuse, the second fuse and the third fuse more obvious, and the matching between the first fuse, the second fuse and the third fuse is better, thereby effectively improving the overall protection effect of the energy storage system and ensuring the safe and efficient operation of the energy storage system.

[0018] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present disclosure will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 is a circuit diagram of an energy storage system proposed in one embodiment of the present disclosure;

[0021] Figure 2 It is a flow chart of a hierarchical fusing matching method for an energy storage system proposed in one embodiment of the present disclosure;

[0022] Figure 3 is an IT curve diagram of a device in a single level in an energy storage system proposed in an embodiment of the present disclosure;

[0023] Figure 4 It is a third-level fuse I in the energy storage system proposed in an embodiment of the present disclosure. 2 t comparison chart;

[0024] Figure 5 It is a graph of IT curve of a three-level fuse in an energy storage system proposed in an embodiment of the present disclosure;

[0025] As shown in the figure: 1. Primary system, 2. Secondary system, 3. Tertiary system, 4. DC combiner box, 5. High voltage box. DETAILED DESCRIPTION

[0026] Embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present disclosure, and are not to be construed as limitations of the present disclosure. On the contrary, the embodiments of the present disclosure include all changes, modifications, and equivalents that fall within the spirit and connotation of the appended claims.

[0027] like Figure 1 As shown, an embodiment of the present disclosure proposes an energy storage system, including: a primary system 1 and a first fuse for short-circuit protection of the primary system 1, the primary system 1 includes: a plurality of secondary systems 2 and a second fuse for short-circuit protection of the secondary systems 2, the secondary system 2 includes: a plurality of tertiary systems 3 and a third fuse for short-circuit protection of the tertiary systems 3.

[0028] It can be understood that the energy storage system has three levels, namely primary system 1, secondary system 2 and tertiary system 3, and the primary system 1 is protected against short circuit by a first fuse, the secondary system 2 is protected against short circuit by a secondary fuse, and the tertiary system 3 is protected against short circuit by a third fuse.

[0029] However, due to the poor matching between the first fuse, the second fuse and the third fuse, the overall protection effect of the energy storage system is poor, which seriously affects the safe and efficient operation of the energy storage system.

[0030] like Figure 2 , Figure 4 and Figure 5 As shown, the embodiment of the present disclosure provides a hierarchical fuse matching method for an energy storage system, including:

[0031] S1: Obtain the expected short-circuit time of the energy storage system;

[0032] S2: When the expected short-circuit time is less than the preset time, the pre-arc I of the third fuse is controlled 2 t is greater than the second fuse I 2 t, and the pre-arc I 2 t is greater than the first fuse I 2 t;

[0033] S3: When the expected short-circuit time is not less than the preset time, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is controlled to be greater than the fusing time of the first fuse.

[0034] It is understandable that when the expected short-circuit time is less than the preset time, the overall short-circuit duration is short, and it can be considered that the short-circuit energy is fully used to melt the fuse, so I 2 t is matched, specifically: the arc pre-arc I 2 t is greater than the second fuse I 2 t, and the pre-arc I 2 t is greater than the first fuse I 2 t; when the expected short-circuit time is not less than the preset time, the overall short-circuit duration is longer, the fuse will dissipate heat, and the short-circuit energy cannot be fully used to melt the fuse. Therefore, the IT curve is used for matching, specifically: the melting time of the third fuse is greater than the melting time of the second fuse, and the melting time of the second fuse is greater than the melting time of the first fuse.

[0035] Thus, by comparing the expected short circuit time with the preset time and adopting I 2 t is matched. When the short circuit lasts for a long time, the IT curve is used for matching, which can make the graded fuse protection of the first fuse, the second fuse and the third fuse more obvious, and the matching between the first fuse, the second fuse and the third fuse is better, thereby effectively improving the overall protection effect of the energy storage system and ensuring the safe and efficient operation of the energy storage system.

[0036] It should be noted that the I 2 t refers to the total heat energy absorbed by the fuse during the melting process, which is the integral of the square of the current and time. It reflects the fuse's ability to respond to different energy shocks.

[0037] Specifically, I 2 t is divided into front arc I 2 t and fuse I 2 t.

[0038] Forearc I 2 t refers to the energy absorbed by the fuse element from the beginning of melting to the moment the arc is generated, that is, the integral of the square of the current before the fuse melts and the time. This stage usually occurs before the fuse element melts, the time is short (generally in milliseconds), and is mainly related to the structure and design of the fuse.

[0039] Fuse I 2 t(Total I 2 t) refers to the total energy absorbed by the fuse from the beginning of melting to the final complete melting (including arc extinction), which is equal to the pre-arc I 2 t plus the arc phase I 2 t(i.e. arc burning I 2 t), reflects the total heat absorbed by the fuse during the melting process.

[0040] When the expected short-circuit time is less than the preset time, the pre-arc I 2 t>Blowing of the second fuse I 2 t, and the pre-arc I 2 t>Blowing of the first fuse I 2 t.

[0041] The IT curve of a fuse is used to describe the melting time of a fuse under different currents. Specifically, the IT curve fully reflects the melting time of a fuse under different current loads. The horizontal axis represents the current (in amperes) and the vertical axis represents the melting time (in seconds). Through the IT curve of a fuse, you can intuitively see the melting time of a fuse under a specific current.

[0042] In this embodiment, the IT curve of the fuse can be arranged in combination with the pre-arcing time-current characteristic curves of the first fuse, the second fuse and the third fuse.

[0043] When the expected short-circuit time is not less than the preset time, the fusing time of the third fuse is greater than the fusing time of the second fuse and greater than the fusing time of the first fuse.

[0044] The preset time can be set according to actual needs and there is no restriction on this.

[0045] like Figure 3 As shown, in some embodiments, the method further includes:

[0046] A first tolerance time of a protected device in the primary system is obtained, and a fusing time of a first fuse is controlled to be less than the first tolerance time.

[0047] It is understandable that the matching is performed according to the first tolerance time of the protected device in the primary system, specifically: when a short-circuit current is generated, the fusing time of the first fuse is less than the first tolerance time, that is, the fusing time of the first fuse is faster than the first tolerance time, so that when a short circuit occurs, the first fuse can act quickly and thus not damage the protected device in the primary system. In this way, the effective matching of the first fuse and the protected device in the primary system is achieved, thereby improving the protection effect of the primary system and ensuring the safe and efficient operation of the energy storage system.

[0048] It should be noted that the first tolerance time can be obtained according to the IT curve of the protected device in the primary system. The IT curve of the protected device can be sorted out in combination with the pre-arcing time current characteristic curve of the first fuse and the tolerance characteristics of the protected device.

[0049] The protected devices in the primary system can be relays, cables, etc.

[0050] The blowing time of the first fuse refers to the time required from the current in the circuit exceeding the rated value to the first fuse melting and cutting off the circuit.

[0051] The first withstand time of a protected device in a primary system refers to the maximum time that the device can withstand an overcurrent or short circuit condition without being damaged or having its performance degraded.

[0052] like Figure 3 As shown, in some embodiments, the method further includes:

[0053] A second tolerance time of the protected device in the secondary system is obtained, and a fusing time of the second fuse is controlled to be less than the second tolerance time.

[0054] It is understandable that the matching is performed according to the second tolerance time of the protected device in the secondary system, specifically: when a short-circuit current is generated, the fusing time of the second fuse is less than the second tolerance time, that is, the fusing time of the second fuse is faster than the second tolerance time, so that when a short circuit occurs, the second fuse can act quickly and thus not damage the protected device in the secondary system. In this way, the effective matching of the second fuse and the protected device in the secondary system is achieved, thereby improving the protection effect of the secondary system and ensuring the safe and efficient operation of the energy storage system.

[0055] It should be noted that the second tolerance time can be obtained according to the IT curve of the protected device in the secondary system. The IT curve of the protected device can be arranged in combination with the pre-arcing time current characteristic curve of the second fuse and the tolerance characteristics of the protected device.

[0056] The protected devices in the secondary system can be relays, cables, etc.

[0057] The fusing time of the second fuse refers to the time required from the current in the circuit exceeding the rated value to the second fuse melting and cutting off the circuit.

[0058] The second withstand time of a protected device in a secondary system refers to the maximum time the device can withstand an overcurrent or short circuit condition without being damaged or having its performance degraded.

[0059] like Figure 3 As shown, in some embodiments, the method further includes:

[0060] A third tolerance time of the protected device in the three-level system is obtained, and a fusing time of the third fuse is controlled to be less than the third tolerance time.

[0061] A second tolerance time of the protected device in the secondary system is obtained, and a fusing time of the second fuse is controlled to be less than the second tolerance time.

[0062] It can be understood that matching is performed according to the third tolerance time of the protected device in the three-level system, specifically: when a short-circuit current occurs, the fusing time of the third fuse is less than the third tolerance time, that is, the fusing time of the third fuse is faster than the third tolerance time, so that when a short circuit occurs, the third fuse can act quickly and thus not damage the protected device in the three-level system. In this way, the effective matching of the third fuse and the protected device in the three-level system is achieved, thereby improving the protection effect of the three-level system and ensuring the safe and efficient operation of the energy storage system.

[0063] It should be noted that the third tolerance time can be obtained according to the IT curve of the protected device in the three-level system. The IT curve of the protected device can be sorted out in combination with the pre-arcing time current characteristic curve of the third fuse and the tolerance characteristics of the protected device.

[0064] The protected devices in the three-level system can be relays, cables, etc.

[0065] The fusing time of the third fuse refers to the time required from the current in the circuit exceeding the rated value to the third fuse melting and cutting off the circuit.

[0066] The third withstand time of the protected device in the three-level system refers to the maximum time that the device can withstand an overcurrent or short circuit condition without being damaged or having its performance degraded.

[0067] In some embodiments, the method further comprises:

[0068] The fusing time of the first fuse is controlled to be less than half of the first tolerance time.

[0069] It can be understood that controlling the blowing time of the first fuse to be less than half of the first tolerance time can leave a larger safety margin between the first fuse and the protected device in the primary system, thereby ensuring that the first fuse provides stable protection for the protected device in the primary system.

[0070] In some embodiments, the method further comprises:

[0071] The fusing time of the second fuse is controlled to be less than half of the second tolerance time.

[0072] It can be understood that controlling the melting time of the second fuse to be less than half of the second tolerance time can leave a larger safety margin between the second fuse and the protected device in the secondary system, thereby ensuring that the second fuse provides stable protection for the protected device in the secondary system.

[0073] In some embodiments, the method further comprises:

[0074] The fusing time of the third fuse is controlled to be less than half of the third tolerance time.

[0075] It can be understood that controlling the blowing time of the third fuse to be less than half of the third tolerance time can leave a larger safety margin between the third fuse and the protected device in the three-level system, thereby ensuring that the third fuse provides stable protection for the protected device in the three-level system.

[0076] It should be noted that the fuse breaking time t1 is less than half of the tolerance time t2 and can be expressed as:

[0077] t1<0.5×t2.

[0078] In some embodiments, the method further comprises:

[0079] Determine the derating factor;

[0080] Obtaining the rated current of the first fuse according to the peak current and the derating factor of the primary system;

[0081] Obtain the rated current of the second fuse according to the peak current and the derating factor of the secondary system;

[0082] The rated current of the third fuse is obtained according to the peak current and the derating factor of the three-level system.

[0083] It can be understood that the rated current of the first fuse is obtained based on the peak current and derating factor of the primary system, thereby determining the rated current of the first fuse to ensure stable protection of the protected device in the primary system by the first fuse; the rated current of the second fuse is obtained based on the peak current and derating factor of the secondary system, thereby determining the rated current of the second fuse to ensure stable protection of the protected device in the secondary system by the second fuse; the rated current of the third fuse is obtained based on the peak current and derating factor of the tertiary system, thereby determining the rated current of the third fuse to ensure stable protection of the protected device in the tertiary system by the third fuse.

[0084] It should be noted that the rated current of the fuse is based on the peak current of the level and the derating factor. The derating factor can be set according to actual needs and there is no restriction on this.

[0085] In some embodiments, the rated current of the first fuse is equal to the peak current of the primary system divided by a derating factor.

[0086] It can be understood that the rated current of the first fuse is obtained by dividing the peak current of the primary system by the derating factor, so that the first fuse can ensure stable protection of the protected device in the primary system based on the determination of the rated current.

[0087] In some embodiments, the rated current of the second fuse is equal to the peak current of the secondary system divided by the derating factor;

[0088] It can be understood that the rated current of the second fuse is obtained by dividing the peak current of the secondary system by the derating factor, so that the second fuse can ensure stable protection of the protected device in the secondary system based on the determination of the rated current.

[0089] In some embodiments, the rated current of the third fuse is equal to the peak current of the three-level system divided by the derating factor.

[0090] It can be understood that the rated current of the third fuse is obtained by dividing the peak current of the three-level system by the derating factor, so that the third fuse can ensure stable protection of the protected device in the three-level system based on the determination of the rated current.

[0091] It should be noted that the rated current In of the fuse is equal to the peak current Irms of the system at the same level divided by the derating factor K, which can be expressed as: In=Irms / K.

[0092] In some embodiments, the derating factor is equal to the product of the ambient temperature derating factor, the connection device heat conduction derating factor, the air cooling derating factor, the frequency derating factor, and the altitude derating factor.

[0093] It can be understood that the derating factor is determined based on the product of the ambient temperature derating factor, the connecting device thermal conduction derating factor, the air cooling derating factor, the frequency derating factor and the altitude derating factor, thereby ensuring the accurate acquisition of the fuse rated current and further ensuring the stable protection of the fuse to the protected device.

[0094] It should be noted that the derating factor K is equal to the product of the ambient temperature derating factor Kt, the connection device heat conduction derating factor Ke, the air cooling derating factor Kv, the frequency derating factor Kf and the altitude derating factor Ka, which can be expressed as:

[0095] K=Kt×Ke×Kv×Kf×Ka.

[0096] In some embodiments, the derating factor is not less than 0.5.

[0097] In some embodiments, the derating factor is no greater than 0.8.

[0098] It should be noted that the derating factor can be set within the range of 0.5-0.8 as required. For example, the derating factor can be 0.5, 0.6, 0.7, 0.8, etc.

[0099] In some embodiments, the preset time is 0.1 s;

[0100] Among them, when the expected short-circuit time is less than 0.1s, the arc pre-arcing I 2 t is greater than the second fuse I 2 t, and the pre-arc I 2 t is greater than the first fuse I 2 t;

[0101] When the expected short-circuit time is not less than 0.1 s, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is controlled to be greater than the fusing time of the first fuse.

[0102] It is understandable that when the expected short-circuit time is less than 0.1s, the overall short-circuit duration is short, and it can be considered that the short-circuit energy is all used to melt the fuse, so I 2 t is matched, specifically: the arc pre-arc I 2 t is greater than the second fuse I 2 t, and the pre-arc I 2 t is greater than the first fuse I 2t; When the expected short-circuit time is not less than 0.1s, the overall short-circuit duration is longer, the fuse will dissipate heat, and the short-circuit energy cannot be fully used to melt the fuse. Therefore, the IT curve is used for matching. Specifically, the melting time of the third fuse is greater than the melting time of the second fuse, and the melting time of the second fuse is greater than the melting time of the first fuse.

[0103] like Figure 1 As shown, in some embodiments, the primary system 1 is a battery stack (SYSTEM), and the first fuse is connected in series in the DC combiner box 4 of the battery stack and used for short-circuit protection of the battery stack; the secondary system 2 is a battery cluster (RACK), and the second fuse is connected in series in the high-voltage box 5 of the battery cluster and used for short-circuit protection of the battery cluster; the tertiary system 3 is a battery pack (PACK), and the third fuse is connected in series in the battery pack and used for short-circuit protection of the battery pack. Among them, the battery stack includes: a plurality of battery clusters connected in series and / or in parallel, and the battery cluster includes: a plurality of battery packs connected in series and / or in parallel, and the battery pack includes: a plurality of single cells connected in series and / or in parallel.

[0104] It can be understood that the energy storage system has three levels, namely battery stack, battery cluster and battery pack, and the battery stack is short-circuit protected by a first fuse, the battery cluster is short-circuit protected by a secondary fuse, and the battery pack is short-circuit protected by a third fuse.

[0105] Furthermore, by comparing the expected short circuit time with the preset time and adopting I 2 t is matched. When the short circuit lasts for a long time, the IT curve is used for matching, which can make the graded fuse protection of the first fuse, the second fuse and the third fuse more obvious, and the matching between the first fuse, the second fuse and the third fuse is better, thereby effectively improving the overall protection effect of the battery stack, battery cluster and battery pack, and ensuring the safe and efficient operation of the energy storage system.

[0106] It should be noted that the DC combiner box 4 (DC combiner cabinet) is a key device for connecting the battery cluster and the power conversion system (PCS), which can realize the parallel connection and convergence function of the battery cluster, electrical protection function, monitoring and control function, power supply function, etc. The DC combiner box 4 is a key interface device between the battery system and the power grid. For example, in a 500kW energy storage system, multiple battery clusters are connected in parallel through the DC combiner box 4, output to the power conversion system (PCS), and finally connected to the power grid.

[0107] The high-voltage box 5 is a key device for connecting the battery cluster and the DC combiner box 4. It can realize electrical connection function, electrical protection function, monitoring and control function, etc. In the energy storage system, the high-voltage box 5 is mainly used to connect the battery cluster and the DC combiner box 4 to collect the outputs of multiple battery clusters to the DC combiner box 4, and cooperate with the second fuse to protect the battery system from overcurrent and short circuit damage.

[0108] Furthermore, when multiple battery clusters (RACK) in a battery stack (SYSTEM) are arranged in parallel, Ipack=Irack, Isystem=N×Irack, where Ipack is the battery pack current, Irac is the battery cluster current, Isystem is the battery stack current, and N is the number of battery clusters in parallel.

[0109] Based on this, when the expected short-circuit time is less than the preset time, the pre-arc I 2 t>Blowing of the second fuse I 2 t, and the pre-arc I 2 t>Blowing of the first fuse I 2 t / N 2 .

[0110] It should be noted that, in the description of the present disclosure, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present disclosure, unless otherwise specified, the meaning of "plurality" is two or more.

[0111] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present disclosure includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present disclosure belong.

[0112] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0113] Although the embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A hierarchical fusing matching method for an energy storage system, characterized in that: The energy storage system comprises: a primary system and a first fuse for short-circuit protection of the primary system, the primary system comprises: a plurality of secondary systems and a second fuse for short-circuit protection of the secondary systems, the secondary system comprises: a plurality of tertiary systems and a third fuse for short-circuit protection of the tertiary systems, wherein the method comprises: Obtaining an expected short-circuit time of the energy storage system; When the expected short-circuit time is less than the preset time, the pre-arc I of the third fuse is controlled 2 t is greater than the melting point of the second fuse 2 t, and the pre-arcing I 2 t is greater than the melting point of the first fuse 2 t; When the expected short-circuit time is not less than the preset time, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is controlled to be greater than the fusing time of the first fuse.

2. The hierarchical fusing matching method of the energy storage system according to claim 1, characterized in that: The method further comprises: Acquire a first tolerance time of a protected device in the primary system, and control a fusing time of the first fuse to be less than the first tolerance time; and / or, Acquire a second tolerance time of a protected device in the secondary system, and control a fusing time of the second fuse to be less than the second tolerance time; and / or, A third tolerance time of the protected device in the three-level system is obtained, and a fusing time of the third fuse is controlled to be less than the third tolerance time.

3. The hierarchical fusing matching method of the energy storage system according to claim 2, characterized in that: The method further comprises: Controlling the fusing time of the first fuse to be less than half of the first tolerance time; and / or, Controlling the fusing time of the second fuse to be less than half of the second tolerance time; and / or, The fusing time of the third fuse is controlled to be less than half of the third tolerance time.

4. The hierarchical fusing matching method for the energy storage system according to claim 1, characterized in that: The method further comprises: Determine the derating factor; Obtaining a rated current of the first fuse according to the peak current of the primary system and the derating factor; Obtaining a rated current of the second fuse according to the peak current of the secondary system and the derating factor; The rated current of the third fuse is obtained according to the peak current of the three-level system and the derating factor.

5. The hierarchical fusing matching method for the energy storage system according to claim 4, characterized in that: The rated current of the first fuse is equal to the peak current of the primary system divided by the derating factor; and / or, The rated current of the second fuse is equal to the peak current of the secondary system divided by the derating factor; and / or, The rated current of the third fuse is equal to the peak current of the three-level system divided by the derating factor.

6. The hierarchical fusing matching method for the energy storage system according to claim 4, characterized in that: The derating factor is equal to the product of the ambient temperature derating factor, the connecting device heat conduction derating factor, the air cooling derating factor, the frequency derating factor and the altitude derating factor.

7. The hierarchical fusing matching method for an energy storage system according to claim 4, characterized in that: The derating factor is not less than 0.

5.

8. The hierarchical fusing matching method for an energy storage system according to claim 4, characterized in that: The derating factor is not greater than 0.

8.

9. The hierarchical fusing matching method for an energy storage system according to claim 1, characterized in that: The preset time is 0.1s; Wherein, when the expected short-circuit time is less than 0.1s, the arc pre-arcing I of the third fuse is controlled. 2 t is greater than the melting point of the second fuse 2 t, and the pre-arcing I 2 t is greater than the melting point of the first fuse 2 t; When the expected short-circuit time is not less than 0.1 s, the fusing time of the third fuse is controlled to be greater than the fusing time of the second fuse, and the fusing time of the second fuse is controlled to be greater than the fusing time of the first fuse.

10. The hierarchical fusing matching method for an energy storage system according to any one of claims 1 to 9, characterized in that: The primary system is a battery stack, and the first fuse is connected in series in a DC combiner box of the battery stack and is used for short-circuit protection of the battery stack; The secondary system is a battery cluster, and the second fuse is connected in series in the high-voltage box of the battery cluster and is used for short-circuit protection of the battery cluster; The three-stage system is a battery pack, and the third fuse is connected in series in the battery pack and is used for short-circuit protection of the battery pack; The battery stack includes: a plurality of battery clusters connected in series and / or in parallel, and the battery cluster includes: a plurality of battery packs connected in series and / or in parallel, and the battery pack includes: a plurality of single cells connected in series and / or in parallel.

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