An energy storage system

Abstract

The energy storage system provided by the embodiment of the present application comprises a grounding net and an energy storage device, the grounding net is buried below the ground where the energy storage device is located; the energy storage device comprises a plurality of grounding terminals, at least part of the grounding terminals are of different grounding types; the grounding types include at least one of working grounding, protection grounding and lightning protection grounding; the plurality of grounding terminals are connected with the grounding net respectively, which realizes the co-networking and non-co-line of different grounding types, avoids the mutual interference of different grounding types, and improves the safety and reliability of the energy storage system.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and more particularly to an energy storage system. Background Technology

[0002] Existing energy storage systems typically include numerous components such as battery packs, energy storage converters, transformers, and monitoring equipment. Each component requires different grounding types. For example, there is protective grounding for the battery pack, lightning protection grounding to reduce the impact of surge currents, and working grounding to provide a zero-potential reference for the energy storage converter, transformer, and other operating equipment. However, in existing grounding methods, these different components are usually connected in parallel to the same busbar for unified grounding. This results in a mixed connection of different grounding types, causing mutual interference between them and reducing the safety and reliability of the energy storage system. Summary of the Invention

[0003] This invention provides an energy storage system that achieves shared grounding grid but not shared grounding lines by employing a grounding grid, thus avoiding mutual interference between different grounding types and improving the safety and reliability of the energy storage system.

[0004] This invention provides an energy storage system, including a grounding grid and an energy storage device. The grounding grid is buried below the ground where the energy storage device is located. The energy storage device includes multiple grounding terminals, each with a different grounding type. The grounding terminals include at least one of working grounding, protective grounding, and lightning protection grounding. Each of the multiple grounding terminals is connected to the grounding grid.

[0005] The beneficial effects of this invention are as follows: The energy storage system provided in this embodiment of the invention achieves the goal of different grounding types sharing the same grid but not the same line by burying a grounding grid below the ground where the energy storage device is located and connecting the grounding terminals of different grounding types to the grounding grid respectively, thereby avoiding mutual interference between the grounding terminals of different grounding types and improving the safety and reliability of the energy storage system. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the structure of an energy storage system provided in an embodiment of the present invention; Figure 2 This is a side view of an energy storage system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the grounding grid structure provided in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the connection relationship between an insulation monitoring device and a battery pack provided in an embodiment of the present invention; Figure 5This is a schematic diagram illustrating the connection relationship between another insulation monitoring device and a battery pack provided in an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the connection relationship between an insulation monitoring device and a battery pack, as provided in another embodiment of the present invention. Figure 7 This is a schematic diagram showing the connection relationship between each cabinet and the grounding grid provided in the embodiments of the present invention; Figure 8 This is a schematic diagram of the energy storage cabinet provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of the combiner cabinet provided in an embodiment of the present invention.

[0007] Figure label: 100 - Grounding grid, 200 - Energy storage device, 300 - Ground, 210 - Multiple grounding terminals, 110 - Grounding electrode, 120 - Grounding wire, 130 - Grounding bolt, 211 - First grounding terminal, 220 - Battery pack, 221 - Positive terminal, 224 - Negative terminal, 230 - Insulation monitoring device, 241 - Positive DC bus, 242 - Negative DC bus, 243 - First switch, 244 - Second switch, 222 - Battery, 223 - Battery switch 250-Battery Management System, 201-Energy Storage Cabinet, 202-Combiner Cabinet, 2013-Energy Storage Cabinet Body, 2014-First Protective Grounding Conductor, 212-Second Grounding Terminal, 213-Third Grounding Terminal, 2022-Protective Grounding Busbar, 2023-Second Protective Grounding Conductor, 2024-Third Protective Grounding Conductor, 2025-Communication Grounding Busbar, 2026-Communication Cable, 2027-Surge Protection Grounding Busbar, 2028-Fourth Protective Grounding Conductor. Detailed Implementation

[0008] The specific embodiments of an energy storage system provided by the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0009] This invention provides an energy storage system, such as Figure 1 As shown, it may include a grounding grid 100 and an energy storage device 200. The grounding grid 100 is buried below the ground 300 where the energy storage device 200 is located. The energy storage device 200 includes multiple grounding terminals 210 (e.g., ...). Figure 1 As shown in the dashed box, at least some of the grounding terminals 210 have different grounding types; the grounding types include at least one of working grounding, protective grounding, and lightning protection grounding; the multiple grounding terminals 210 are respectively connected to the grounding grid 100.

[0010] in, Figure 1 The example shown uses two grounding terminals. In practice, the number of grounding terminals is not limited to two, and the arrangement of the grounding terminals is also not limited to... Figure 1 As shown in the image.

[0011] The energy storage system provided in the embodiments of the present invention, such as Figure 1 The grounding grid 100 shown is buried below the ground 300 where the energy storage device 200 is located. Therefore, multiple grounding terminals 210 with different positions and functions in the energy storage device 200 can be connected to the same grounding grid 100, realizing the grounding of multiple grounding terminals 210.

[0012] It should be noted that the function of the grounding terminal differs in different grounding types. In lightning protection grounding, the grounding terminal is used to draw out surge current from the energy storage device, preventing damage. Therefore, a large overcurrent is required at the grounding terminal in lightning protection grounding. In functional grounding, the grounding terminal provides a potential reference for the energy storage device, enabling its normal operation. In protective grounding, the grounding terminal promptly draws out accumulated charge from the energy storage device, preventing electric shock to personnel or damage to electrical components, ensuring the safety of the energy storage device. When different grounding types share a grounding terminal, they can interfere with each other. For example, during lightning protection grounding, a large overcurrent at the grounding terminal can prevent it from providing an accurate potential reference for the functional ground, causing the energy storage device to malfunction and creating a safety hazard. The energy storage system provided in this embodiment of the invention uses multiple grounding terminals of different types, avoiding mutual interference caused by different grounding types sharing a grounding terminal. This improves the reliability of the energy storage device while reducing safety hazards, thus enhancing the safety and reliability of the energy storage device.

[0013] In some embodiments, such as Figure 2 As shown, the energy storage system also includes multiple grounding wires 120; the energy storage device 200 also includes multiple grounding bolts 130; the grounding grid 100 includes multiple grounding electrodes 110; the multiple grounding wires 120 are connected between the multiple grounding bolts 130 and the multiple grounding electrodes 110, and the multiple grounding bolts 130, the multiple grounding wires 120 and the multiple grounding electrodes 110 are connected in a one-to-one correspondence.

[0014] In this way, the multiple grounding bolts 130 on the energy storage device 200 can be more tightly connected to the grounding wire 120, and the grounding bolts 130, grounding wire 120, and grounding electrode 110 are connected one-to-one. This enables multiple grounding terminals 210 to be connected to the grounding grid 100 respectively. When the grounding bolts 130, grounding wire 120, and grounding electrode 110 are connected one-to-one, the connection between the grounding bolts 130 and grounding wire 120 does not require welding, thus offering advantages such as easy assembly, convenient disassembly and maintenance, and greater layout flexibility in application scenarios requiring mobile energy storage devices.

[0015] In some embodiments, any one of the multiple grounding electrodes is made of hot-dip galvanized angle steel or copper-clad steel. It should be understood that hot-dip galvanized angle steel refers to a structure where angle steel is immersed in molten zinc to form a zinc-iron alloy on its surface. This zinc-iron alloy enhances the corrosion resistance of the angle steel while maintaining good electrical conductivity. Copper-clad steel refers to a structure where a copper layer is tightly coated onto a steel core. This structure offers better electrical conductivity and corrosion resistance, and compared to pure copper, it has advantages such as lower cost and higher structural strength. The grounding electrode provided in this embodiment is made of the above materials, allowing it to carry a large current without overheating when connected to lightning protection grounding, thus improving safety. Furthermore, the angled structure of the hot-dip galvanized angle steel facilitates the installation and connection between the grounding electrode and the grounding grid, improving installation convenience.

[0016] Of course, the grounding electrode can also be made of other materials with good conductivity and corrosion resistance, such as copper-aluminum alloy or pure copper, and is not limited here.

[0017] In some embodiments, such as Figure 3 As shown, the grounding grid 100 has a mesh structure.

[0018] Thus, the mesh-like grounding grid 100 can be made by splicing together strips of conductive material, reducing the difficulty and cost of manufacturing. Furthermore, as... Figure 3 As shown, the grid-like grounding grid 100 enables multiple grounding terminals 210 in the energy storage device (not shown in the figure) to be connected to the nearest grounding grid 100 as long as they are located above the grounding grid 100, regardless of their specific location, and to achieve equipotential grounding through the interconnected conductive network.

[0019] Of course, the grounding grid 100 can also be a tree structure or other easily connected structures, which are not limited here.

[0020] In some embodiments, the grounding grid is made of hot-dip galvanized flat steel. It should be understood that hot-dip galvanized flat steel refers to flat steel that has been immersed in molten zinc to form a zinc-iron alloy structure on its surface. This zinc-iron alloy enhances the corrosion resistance of the flat steel while also providing good electrical conductivity. Using hot-dip galvanized flat steel to fabricate buried grounding grids not only saves significant costs but also improves corrosion resistance and extends the service life of the grounding grid. Furthermore, the flat structure of hot-dip galvanized flat steel makes it more suitable for vertical and horizontal stacking connections, making it ideal for applications where grounding grids are buried underground and overlap vertically.

[0021] Of course, the grounding grid can also be made of other materials with good conductivity and corrosion resistance, such as flat copper strip or copper-clad steel.

[0022] In some embodiments, such as Figure 4 As shown, the energy storage device also includes: a battery pack 220 and an insulation monitoring device 230; the insulation monitoring device 230 is used to: monitor the resistance between the electrodes of the battery pack 220 and the first grounding terminal 211, and determine that the electrodes of the battery pack 220 and the first grounding terminal 211 are insulated when the monitored resistance value is greater than a threshold; the first grounding terminal 211 is the grounding terminal of the plurality of grounding terminals 210 whose grounding type is the protective grounding, and the electrodes of the battery pack 220 include at least one of the positive electrode 221 and the negative electrode 224.

[0023] The insulation monitoring device 230 can be connected to the positive terminal 221 and the first grounding terminal 211 of the battery pack 220 respectively, but not to the negative terminal 224 (not shown in the figure); or, the insulation monitoring device 230 can be connected to the negative terminal 224 and the first grounding terminal 211 of the battery pack 220 respectively, but not to the positive terminal 221 (not shown in the figure); or, the insulation monitoring device 230 can be connected to the positive terminal 221, the negative terminal 224 and the first grounding terminal 211 of the battery pack 220 respectively, such as... Figure 4 As shown.

[0024] Thus, the insulation monitoring device 230 is connected to the electrodes of the battery pack 220, which enables the monitoring of the insulation between the electrodes of the battery pack 220 and the first grounding terminal 211, thereby determining whether the electrodes of the battery pack 220 have failed to maintain insulation. When the detected resistance value is less than or equal to the threshold, it can be determined that the electrodes of the battery pack 220 have failed to maintain insulation, thus providing a reference for the safe use of energy storage equipment.

[0025] In some embodiments, the insulation monitoring device 230 can be directly connected to the electrodes of the battery pack 220, such as... Figure 4As shown. Further, a first switch 243 can be provided between the positive terminal 221 and the positive DC bus 241 of the battery pack 220, and a second switch 244 can be provided between the negative terminal 224 and the negative DC bus 242 of the battery pack 220. When the first switch 243 and the second switch 244 are closed, the positive terminal 221 and the positive DC bus 241 of the battery pack 220 are connected, and the negative terminal 224 and the negative DC bus 242 of the battery pack 220 are connected. If the insulation monitoring device 230 detects an insulation failure in a battery pack 220, the battery management system can control the first switch 243 and the second switch 244 corresponding to the battery pack 220 with insulation failure to open, thereby disconnecting the positive terminal 221 and the positive DC bus 241 of the battery pack 220 with insulation failure, and disconnecting the negative terminal 224 and the negative DC bus 242 of the battery pack with insulation failure.

[0026] In this way, by monitoring whether any one of the positive or negative terminals of the battery pack 220 has insulation failure through the insulation monitoring device 230, the battery pack 220 with insulation failure can be accurately located and identified, thereby enabling the control of the energy storage system.

[0027] Furthermore, when the insulation monitoring device 230 detects an insulation failure between the positive terminal 221 or the negative terminal 224 of the battery pack 220 and the first grounding terminal 211, for example, when the detected resistance value is less than or equal to a threshold, it can issue an alarm signal or send a signal to the battery management system (BMS). Figure 4 (Not shown in the image) An alarm message is issued, and the battery management system controls the battery pack 220 with insulation failure to stop working.

[0028] Thus, if the insulation of the battery pack 220 fails without real-time monitoring and alarm, the battery pack 220 casing and even the casing of the energy storage device will become electrified. An electrified casing can affect the normal operation of some components within the energy storage device and poses a risk of electric shock to personnel upon contact, especially since energy storage devices typically operate at high voltages, posing a significant safety hazard. Therefore, the insulation monitoring device 230 monitors the insulation of the battery pack 220 in real time and issues alarm signals or sends signals to the battery management system (BMS). Figure 4 (Not shown in the image) Issues an alarm message, and the battery management system controls the battery pack with insulation failure to stop working, which can improve the safety of the energy storage system and reduce the risk of electric shock to personnel.

[0029] Alternatively, in some embodiments, the insulation monitoring device 230 is connected to the DC bus. For example, as... Figure 5As shown, the battery pack 220 is provided in multiple ways. Each battery pack 220 has a total positive terminal and a total negative terminal after being connected. The energy storage device also includes a positive DC bus 241 and a negative DC bus 242. The total positive terminal 221 is connected to the positive DC bus 241, and the total negative terminal 224 is connected to the negative DC bus 242. The insulation monitoring device 230 satisfies at least one of the following connection relationships: the insulation monitoring device 230 is connected to the positive DC bus 241 and the first grounding terminal 211 respectively, and the insulation monitoring device 230 is connected to the negative DC bus 242 and the first grounding terminal 211 respectively.

[0030] When multiple battery packs 220 are connected in series, the positive terminal of the battery pack 220 located at one end is connected to the positive DC bus 241, and the negative terminal of the battery pack 220 located at the other end is connected to the negative DC bus 242, which is the total negative terminal. Alternatively, when multiple battery packs 220 are connected in parallel, each positive terminal connected in parallel can be considered as the total positive terminal, and each negative terminal connected in parallel can be considered as the total negative terminal. Or, when multiple battery packs 220 are connected in a mixed series and parallel manner, the total positive terminal and the total negative terminal of the multiple battery packs 220 can be flexibly determined according to the actual situation.

[0031] The insulation monitoring device 230 can be connected to the DC bus and the first grounding terminal 211 in the following ways: The insulation monitoring device 230 can be connected to the positive DC bus 241 and the first grounding terminal 211 respectively, but not to the negative DC bus 242 (not shown), for monitoring the insulation between the positive DC bus 241 and the first grounding terminal 211; or, the insulation monitoring device 230 can be connected to the negative DC bus 242 and the first grounding terminal 211 respectively, but not to the positive DC bus 241 (not shown), for monitoring the insulation between the negative DC bus 242 and the first grounding terminal 211; or, the insulation monitoring device 230 can be connected to the positive DC bus 241, the negative DC bus 242, and the first grounding terminal 211 respectively, as shown in the diagram. Figure 5 As shown, the insulation between the positive DC bus 241 and the first grounding terminal 211, and the insulation between the negative DC bus 242 and the first grounding terminal 211 are monitored respectively.

[0032] Thus, the insulation monitoring device 230 can monitor whether either the positive DC bus 241 or the negative DC bus 242 has experienced insulation failure, enabling monitoring of the overall insulation failure status of the DC side of the energy storage device, thereby facilitating the control and management of the energy storage system. Furthermore, when monitoring the DC bus, the number of monitoring points can be reduced, thereby reducing the computational load on the insulation monitoring device 230.

[0033] Furthermore, when the insulation monitoring device 230 detects an insulation failure between the positive DC bus 241, the negative DC bus 242, and the first grounding terminal 211, it can issue an alarm signal or notify the battery management system (BMS). Figure 5 (Not shown in the image) An alarm message is issued, and the battery management system controls the energy storage device to stop working in order to carry out maintenance.

[0034] Among them, such as Figure 5 As shown, when a first switch 243 is provided between the positive terminal 221 and the positive DC bus 241 of the battery pack 220, and a second switch 244 is provided between the negative terminal 224 and the negative DC bus 242 of the battery pack 220, the battery pack 220 can be connected to the positive DC bus 241 by closing or opening the first switch 243, and the battery pack 220 can be connected to the negative DC bus 242 by closing or opening the second switch 244.

[0035] Therefore, if the insulation monitoring device 230 detects an insulation failure in either the positive DC bus 241 or the negative DC bus 242, the battery management system (BMS) will activate the circuit breaker. Figure 5 (Not shown in the image) can control the first switch 243 and the second switch 244 to disconnect the battery pack 220 from the DC bus with insulation failure, so that the energy storage device stops working and waits for maintenance.

[0036] Furthermore, the insulation monitoring device 230 monitors the insulation of the DC bus in real time, and promptly alarms and stops the operation of the energy storage device when the insulation of either the positive DC bus 241 or the negative DC bus 242 fails. This can prevent the leakage structure from affecting the normal operation of other components in the energy storage device, thereby improving the safety of the energy storage system and reducing the risk of electric shock to personnel.

[0037] In some embodiments, such as Figure 6 As shown, the battery pack 220 includes a battery 222, and the insulation monitoring device 230 is further used to: monitor the resistance between the battery electrode and the first ground terminal 211, and determine that the battery electrode and the first ground terminal 211 are insulated when the monitored resistance value is greater than a threshold; the battery electrode 222 includes at least one of a positive electrode and a negative electrode.

[0038] When the battery pack 220 includes multiple batteries 222, the batteries 222 can be connected in series, such as... Figure 6 As shown; or the batteries 222 can be connected in parallel, but no diagram is provided; or the batteries 222 can be connected in a combination of series and parallel connections, but no diagram is provided.

[0039] It should be understood that the number of batteries 222 included in the battery pack 220 is not limited to... Figure 6 The two shown here are only for reference. Figure 6 The example shown is for illustration only. The number of batteries 222 included in the battery pack 220 can be designed according to actual needs, and there is no limit here.

[0040] For any given battery 222, the insulation monitoring device 230 can be connected to the positive terminal of battery 222 but not to the negative terminal, or the insulation monitoring device 230 can be connected to the negative terminal of battery 222 but not to the positive terminal, or the insulation monitoring device 230 can be connected to both the positive and negative terminals of battery 222, such as... Figure 6 As shown.

[0041] In this way, by monitoring whether either the positive or negative terminal of the battery 222 has failed insulation through the insulation monitoring device 230, the battery 222 with insulation failure can be accurately located and precisely identified, thereby enabling precise control of the energy storage system.

[0042] Furthermore, when the insulation monitoring device detects a failure in the insulation between the electrode of a battery and the first grounding terminal, it can promptly issue an alarm signal or send an alarm message to the battery management system 250. The battery management system 250 can control the battery switch 223 to close or open, thereby disconnecting the individual battery 222 with insulation failure from the other batteries 222 in the battery pack 220 and stopping its operation. The remaining batteries 222 in the battery pack 220 can be kept connected and maintained in normal operation by the battery switch 223.

[0043] Furthermore, the insulation monitoring device 230 monitors the insulation of the batteries 222 in the battery pack 220 in real time. It can promptly issue an alarm when the insulation of either the positive or negative terminal of battery 222 fails, and control the battery management system 250 to stop the operation of the battery 222 with insulation failure, disconnecting it from the other batteries 222. This prevents the battery 222 with insulation failure (i.e., leakage) from affecting the normal operation of other batteries 222, improving the safety of the energy storage system and reducing the risk of electric shock.

[0044] In some embodiments, such as Figure 6 As shown, the energy storage system includes a battery management system 250, which is used to: output indication information to an insulation monitoring device 230, the indication information being used to indicate whether the battery 222 is in normal operating condition; the insulation monitoring device 230 is specifically used to: determine the battery 222 in normal operating condition based on the received indication information, and monitor the resistance between the electrodes of the battery 222 in normal operating condition and the first ground terminal 211.

[0045] In this context, a battery 222 in normal operating condition refers to a battery 222 whose voltage and temperature are both within the normal range. The battery management system 250 can determine whether the voltage and temperature of the battery 222 are within the normal operating range using temperature, voltage, and other sensors (not shown in the figure) installed in the battery pack 220. This identifies the batteries in normal operating condition and disconnects the batteries 222 in abnormal operating condition via battery switch 223, causing them to stop working. The system can also output indication information to the insulation monitoring device 230, informing it which batteries 222 are in normal operating condition, allowing the insulation monitoring device 230 to monitor the insulation of the batteries 222 in normal operating condition.

[0046] Thus, since the stopped battery 222 is disconnected by the battery switch 223, and the disconnected battery does not affect the insulation of the circuit, the insulation of the stopped battery 222 will not affect the normal operation of the battery pack 220. Furthermore, the insulation monitoring device 230 may also generate false alarms or repeated alarms when monitoring the stopped battery 222. Therefore, by not monitoring the battery 222 in an abnormal operating state, not only are false alarm signals and repeated alarm signals avoided, but the number of batteries 222 monitored by the insulation monitoring device 230 in real time and the amount of computation are also reduced. Thus, while ensuring the safety of the energy storage system, the operating efficiency is improved.

[0047] In some embodiments, such as Figure 7 As shown, when the energy storage device 200 is arranged in multiple cabinets, multiple grounding terminals 210 can be respectively installed in the multiple cabinets.

[0048] In this way, multiple cabinets can be grounded. Since the cabinets in the energy storage system require equipotentiality to operate normally, they need to be connected by wiring to achieve equipotentiality. In this embodiment of the invention, all cabinets are connected to the same grounding network 100. Therefore, it can be considered that the cabinets are interconnected through the grounding network 100, which provides the same potential as a reference for each cabinet, thus achieving equipotential connection between them. Furthermore, since the grounding network 100 is buried underground, the safety hazards caused by laying wiring above ground 300 meters are avoided.

[0049] In some embodiments, the resistance of the grounding grid is less than 1Ω.

[0050] In the energy storage system provided in this embodiment of the invention, the resistance of the grounding grid is less than 1Ω, so the resistance between multiple grounding terminals is also less than 1Ω. The potential difference between multiple grounding terminals is positively correlated with the resistance between multiple grounding terminals. Since the resistance between grounding terminals is less than 1Ω, the potential difference between multiple grounding terminals is small, making each grounding terminal more likely to be at the same potential, thereby reducing the risk of circulating current caused by the potential difference between each grounding terminal.

[0051] Furthermore, when the energy storage system includes multiple cabinets, and different cabinets are connected to the same grounding grid, since the resistance of the grounding grid is less than 1Ω, the resistance between each cabinet is also less than 1Ω. Consequently, the potential difference between each cabinet is small, making each cabinet more likely to be at the same potential, thereby reducing the risk of circulating current between cabinets and improving the safety of the energy storage system.

[0052] In some embodiments, such as Figure 8 As shown, the energy storage device includes an energy storage cabinet 201, which includes a battery 222 and a conductive energy storage cabinet body 2013. The battery 222 is disposed in the energy storage cabinet body 2013. The battery 222 is connected to the energy storage cabinet body through a first protective grounding conductor 2014. The energy storage cabinet body 2013 is also connected to a first grounding terminal 211, which is a grounding terminal with a protective grounding type among multiple grounding terminals.

[0053] Thus, the battery 222 can be connected to the first grounding terminal 211 through the conductive energy storage cabinet 2013, and then the first grounding terminal 211 can be connected to the grounding grid 100, thereby grounding the battery 222. Furthermore, since the distance between the battery 222 and the energy storage cabinet 2013 can be set to be relatively short, the first protective grounding conductor 2014 can be relatively short. Compared with the scheme where the battery 222 is directly connected to the first grounding terminal 211 through the first protective grounding conductor 2014, the scheme provided in this embodiment of the invention can save material for the first protective grounding conductor 2014. Moreover, since the energy storage cabinet 2013 has a large cross-sectional area and a large surface area, its resistance is small and its heat dissipation effect is good. When the battery 222 fails and releases a large current, the energy storage cabinet 2013 has strong overcurrent capacity and good heat dissipation, making it difficult for heat accumulation to cause melting, thus improving the safety of the energy storage cabinet 201.

[0054] It should be understood that the energy storage cabinet 201 typically includes a large number of batteries 222, but to avoid making the attached diagrams overly complex, in... Figure 8 The illustration uses only one battery, 222, as an example.

[0055] In some embodiments, the first protective grounding conductor 2014 is a copper wire.

[0056] It should be understood that copper's material properties determine its low resistance, good conductivity, good corrosion resistance, and resistance to aging and loss of conductivity. Furthermore, it possesses strong deformability, making it suitable for various deployment scenarios. Therefore, using copper wire to make the first protective grounding conductor 2014 can utilize its good conductivity to conduct the large current released during a battery 222 failure to the ground, protecting the energy storage device. Furthermore, copper's good corrosion resistance extends the service life of the first protective grounding conductor 2014, reducing the frequency of line replacement. Additionally, copper's strong deformability also simplifies wiring. Of course, other materials, such as galvanized steel or copper-clad steel, can be chosen based on cost and material properties, depending on the specific circumstances; this is not a limitation here.

[0057] In some embodiments, such as Figure 9 As shown, the energy storage device includes a combiner cabinet 202, which includes a protective grounding busbar 2022 and a conductive combiner cabinet body 2020. The protective grounding busbar 2022 is connected to the combiner cabinet body 2020, and the combiner cabinet body 2020 is also connected to a first grounding terminal 211, which is a grounding terminal with a protective grounding type among multiple grounding terminals.

[0058] Thus, the protective grounding busbar 2022 is connected to the first grounding terminal 211 through the combiner cabinet 2020, and the first grounding terminal 211 is then connected to the grounding grid 100, achieving grounding of the protective grounding busbar 2022. Therefore, the equipment in the combiner cabinet 202 can be grounded by connecting to the protective grounding busbar 2022. This reduces wiring complexity, simplifies grounding of the combiner cabinet 202, and improves the convenience of installing the combiner cabinet 202.

[0059] It should be understood that combiner cabinets typically have partitions, and equipment and various grounding bars can be placed on the corresponding partition surfaces. To avoid making the attached diagrams overly complex, Figure 9 The partition was not shown in the middle.

[0060] In some embodiments, such as Figure 9 As shown, the combiner cabinet 202 also includes AC equipment, which is located in the combiner cabinet body 2020. The AC equipment is connected to the protective grounding busbar 2022 through the second protective grounding conductor 2023.

[0061] In this way, the AC equipment can be grounded by connecting the second protective grounding conductor 2023 to the protective grounding busbar 2022. Furthermore, when setting up the protective grounding busbar 2022, it can be selectively set up in a position closer to the AC equipment, which not only saves the material of the second protective grounding conductor 2023, but also facilitates wiring.

[0062] It should be understood that the AC equipment in combiner cabinet 202 may include, but is not limited to, uninterruptible power supplies, air conditioners, and liquid chillers.

[0063] In some embodiments, the housing of the AC equipment is connected to a second protective grounding conductor.

[0064] In this way, the AC equipment can be connected to the second protective grounding conductor through the housing, thereby achieving grounding. The second protective grounding conductor can be connected to the housing of the AC equipment by welding.

[0065] Of course, when the AC equipment is equipped with a grounding port, it can also be connected to the second protective grounding conductor 2023 through the grounding port in the AC equipment to achieve grounding, which is not limited here.

[0066] In some embodiments, the material of the second protective grounding conductor 2023 may be the same as that of the first protective grounding conductor, or different materials may be used depending on the actual situation, which is not limited here.

[0067] In some embodiments, such as Figure 9 As shown, the combiner cabinet 202 also includes a DC device, which is located in the combiner cabinet body 2020. The DC device is connected to the protective grounding busbar 2022 through the third protective grounding conductor 2024.

[0068] In this way, DC equipment can be grounded by connecting the third protective grounding conductor 2024 to the protective grounding busbar 2022. Furthermore, when setting up the protective grounding busbar 2022, it can be selectively set up in a position closer to the AC equipment, which not only saves the material of the third protective grounding conductor 2024, but also facilitates wiring.

[0069] It should be understood that the DC devices in combiner cabinet 202 may include, but are not limited to, water immersion sensors, fire alarm control panels, and battery management systems.

[0070] In some embodiments, the housing of the DC equipment is connected to a third protective grounding conductor.

[0071] In this way, the DC equipment can be grounded by connecting the housing to the third protective grounding conductor, which can be connected to the housing of the DC equipment by welding.

[0072] Of course, when the DC equipment is equipped with a grounding port, it can also be connected to the third protective grounding conductor 2024 through the grounding port of the DC equipment to achieve grounding, which is not limited here.

[0073] In some embodiments, the material of the third protective grounding conductor 2024 may be the same as that of the first protective grounding conductor, or different materials may be used depending on the actual situation, which is not limited here.

[0074] In some embodiments, such as Figure 9 As shown, the energy storage device includes a combiner cabinet 202, which includes a communication grounding busbar 2025. The communication grounding busbar 2025 is connected to a second grounding terminal 212, which is the grounding terminal with the working grounding type among multiple grounding terminals.

[0075] Thus, by setting a communication grounding busbar 2025 in the combiner cabinet 202, the communication equipment in the combiner cabinet 202 can be connected to the second grounding terminal 212 through the communication grounding busbar 2025, and then the second grounding terminal 212 can be connected to the grounding grid 100 to realize the working grounding of the equipment.

[0076] In some embodiments, such as Figure 9 As shown, the combiner cabinet 202 also includes communication equipment and communication cable 2026. The communication equipment is located inside the combiner cabinet 202 and is connected to the communication cable 2026. The communication equipment is connected through the shielding layer of the communication cable 2026. Figure 9 (Not shown in the image) is connected to the communication grounding busbar 2025.

[0077] Among them, the communication equipment communicates with external devices via communication cable 2026. Figure 9 (Not shown) The connection is used to enable communication between the devices inside the combiner cabinet 202 and external devices, transmitting information signals or control signals. Because the combiner cabinet 202 contains a large number of DC or AC devices, the electromagnetic environment is complex. Therefore, it is necessary to ground the communication equipment and communication cables 2026 to prevent electromagnetic interference between the combiner cabinet 202 and the communication equipment with external devices.

[0078] Thus, the communication equipment passes through the shielding layer in the communication cable 2026 ( Figure 9 (Not shown in the diagram) is connected to the communication grounding busbar 2025, which realizes the working grounding of the communication equipment and protects the signal transmitted by the communication cable 2026 from environmental interference. This ensures the accuracy of the signal when the communication equipment communicates with the outside world and reduces the risk of misoperation caused by signal distortion when other devices in the combiner cabinet 202 respond to external control signals.

[0079] In some embodiments, such as Figure 9 As shown, the energy storage device includes a combiner cabinet 202, which includes a surge protection grounding bus 2027. The surge protection grounding bus 2027 is connected to a third grounding terminal 213, which is the grounding terminal with lightning protection grounding among multiple grounding terminals.

[0080] Thus, by setting up a surge protection grounding busbar 2027 in the combiner cabinet 202, the surge protection device in the combiner cabinet 202 can be connected to the third grounding terminal 213 through the surge protection grounding busbar 2027, and then the third grounding terminal 213 can be connected to the grounding grid 100, thereby realizing the grounding of the surge protection device.

[0081] In some embodiments, such as Figure 9 As shown, the combiner cabinet 202 also includes a surge protection device, which is installed in the combiner cabinet 202 and is connected to the surge protection grounding busbar 2027 through the fourth protective grounding conductor 2028.

[0082] In this way, the surge protection device can be connected to the surge protection grounding busbar 2027 through the fourth protective grounding conductor 2028, thereby achieving lightning protection grounding and timely guiding the surge current in the equipment to the ground electrode, thus protecting the equipment in the combiner cabinet 202 and improving the safety of the combiner cabinet 202.

[0083] In some embodiments, the material of the fourth protective grounding conductor 2028 may be the same as that of the first protective grounding conductor, or different materials may be used depending on the actual situation, which is not limited here.

[0084] In summary, the energy storage system provided in the embodiments of the present invention has the following advantages: 1. When the grounding grid is buried below the ground where the energy storage device is located, multiple grounding points with different locations and functions within the energy storage device can be connected to the same grounding grid, achieving grounding of multiple grounding terminals. Furthermore, by avoiding different grounding types sharing the same grounding terminal, different grounding types are connected to the same grid but not on the same line, thus avoiding the risk of mutual interference when different grounding types are working simultaneously, and improving the safety and reliability of the energy storage system.

[0085] 2. The DC side of the energy storage device is equipped with an insulation monitoring device. This device can detect the insulation of the battery pack electrodes, the DC bus, or the insulation of individual battery electrodes within the battery pack, thereby determining whether the DC side of the energy storage device has experienced insulation failure. This provides a reference for the safe use of the energy storage device. Furthermore, the insulation monitoring device can work in conjunction with the battery management system and switches to stop operation when the insulation of a certain structure (such as an electrode or DC bus) fails, and disconnect it from other structures via a switch. This ensures the safety of the energy storage system, reduces the risk of electric shock to personnel, and improves operational efficiency.

[0086] 3. The grounding grid has a small resistance value, which in turn results in a small resistance between each grounding terminal and each cabinet. As a result, the potential difference caused by the resistance can be ignored, reducing the risk of circulating current and improving the safety of the energy storage system.

[0087] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An energy storage system, characterized in that, The device includes a grounding grid and an energy storage device. The grounding grid is buried below the ground where the energy storage device is located. The energy storage device includes multiple grounding terminals, at least some of which have different grounding types. The grounding types include at least one of functional grounding, protective grounding, and lightning protection grounding. The multiple grounding terminals are respectively connected to the grounding grid.

2. The energy storage system as described in claim 1, characterized in that, The energy storage device also includes: a battery pack and an insulation monitoring device; The insulation monitoring device is used to: monitor the resistance between the electrodes of the battery pack and the first grounding terminal; when the detected resistance value is greater than a threshold, determine that the electrodes of the battery pack and the first grounding terminal are insulated; the first grounding terminal is the grounding terminal of the plurality of grounding terminals whose grounding type is the protective grounding; the electrodes of the battery pack include at least one of positive and negative electrodes.

3. The energy storage system as described in claim 2, characterized in that, The battery pack is provided in multiple parts, and each battery pack is connected to have a total positive terminal and a total negative terminal. The energy storage device also includes a positive DC bus and a negative DC bus. The total positive terminal is connected to the positive DC bus, and the total negative terminal is connected to the negative DC bus. The insulation monitoring device satisfies at least one of the following connection relationships: the insulation monitoring device is connected to the positive DC bus and the first grounding terminal respectively, and the insulation monitoring device is connected to the negative DC bus and the first grounding terminal respectively.

4. The energy storage system as described in claim 2, characterized in that, The battery pack includes a battery, and the insulation monitoring device is further configured to: monitor the resistance between the electrode of the battery and the first grounding terminal, and determine that the electrode of the battery and the first grounding terminal are insulated when the detected resistance value is greater than the threshold value; the electrode of the battery includes at least one of a positive electrode and a negative electrode.

5. The energy storage system as described in claim 4, characterized in that, The energy storage system includes a battery management system, which is used to: output indication information to the insulation monitoring device, the indication information being used to indicate that the battery is in normal operating condition; The insulation monitoring device is specifically used to: determine the battery in the normal operating state according to the received indication information, and monitor the resistance between the electrodes of the battery in the normal operating state and the first ground terminal.

6. The energy storage system as described in claim 1, characterized in that, The energy storage device includes an energy storage cabinet, which includes a battery and a conductive energy storage cabinet body. The battery is located in the energy storage cabinet body. The battery is connected to the energy storage cabinet body through a first protective grounding conductor. The energy storage cabinet body is also connected to a first grounding terminal, which is the grounding terminal of the plurality of grounding terminals whose grounding type is the protective grounding.

7. The energy storage system as described in claim 1, characterized in that, The energy storage device includes a combiner cabinet, which includes a protective grounding busbar and a conductive combiner cabinet body. The protective grounding busbar is connected to the combiner cabinet body, and the combiner cabinet body is also connected to a first grounding terminal, which is the grounding terminal among the plurality of grounding terminals whose grounding type is the protective grounding.

8. The energy storage system as described in claim 7, characterized in that, The combiner cabinet also includes an AC device, which is located in the combiner cabinet and is connected to the protective grounding busbar via a second protective grounding conductor.

9. The energy storage system as described in claim 8, characterized in that, The housing of the AC equipment is connected to the second protective grounding conductor.

10. The energy storage system as described in claim 8, characterized in that, The combiner cabinet also includes a DC device, which is located in the combiner cabinet and is connected to the protective grounding busbar via a third protective grounding conductor.

11. The energy storage system as described in claim 10, characterized in that, The housing of the DC equipment is connected to the third protective grounding conductor.

12. The energy storage system as described in claim 1, characterized in that, The energy storage device includes a combiner cabinet, which includes a communication grounding busbar connected to a second grounding terminal, which is the grounding terminal among the plurality of grounding terminals whose grounding type is the working ground.

13. The energy storage system as described in claim 12, characterized in that, The combiner cabinet also includes communication equipment and communication cables. The communication equipment is located in the combiner cabinet and is connected to the communication cables. The communication equipment is connected to the communication grounding busbar through the shielding layer of the communication cables.

14. The energy storage system as described in claim 1, characterized in that, The energy storage device includes a combiner cabinet, which includes a surge protection grounding busbar. The surge protection grounding busbar is connected to a third grounding terminal, which is the grounding terminal among the plurality of grounding terminals whose grounding type is lightning protection grounding.

15. The energy storage system as described in claim 14, characterized in that, The combiner cabinet also includes a surge protection device, which is installed in the combiner cabinet and is connected to the surge protection grounding busbar through a fourth protective grounding conductor.

16. The energy storage system as described in claim 1, characterized in that, The resistance of the grounding grid is less than 1Ω.

17. The energy storage system as described in claim 1, characterized in that, The energy storage system also includes multiple grounding wires; the energy storage device also includes multiple grounding bolts; the grounding grid includes multiple grounding electrodes; the multiple grounding wires are connected between the multiple grounding bolts and the multiple grounding electrodes, and the multiple grounding bolts, the multiple grounding wires and the multiple grounding electrodes are connected in a one-to-one correspondence.

18. The energy storage system as described in claim 17, characterized in that, The material used to manufacture any one of the plurality of grounding electrodes includes hot-dip galvanized angle steel or copper-clad steel.

19. The energy storage system as described in claim 1, characterized in that, The grounding grid has a mesh structure.

20. The energy storage system according to any one of claims 1-19, characterized in that, The grounding grid is made of hot-dip galvanized flat steel.

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