Marine energy storage system and method of charging the same

Abstract

The embodiment of the application discloses a marine energy storage system and a charging method thereof. The charging method of the marine energy storage system comprises the following steps: receiving a charging instruction for charging the marine energy storage system; acquiring branch voltages of each power supply branch; determining a power-on strategy of the power supply branch according to the branch voltage, and closing a charging switch in a second high-voltage box according to the power-on strategy to power on the power supply branch; and if the power-on of all the power supply branches is completed, the charging switch in a first high-voltage box is closed to charge the battery pack in each power supply branch through the first high-voltage box, so that the voltage consistency of each power supply branch in the charging stage can be ensured, the problem that the voltage consistency between the power supply branches of the marine energy storage system is poor after the charging is completed is avoided, and the reliability and safety of the marine energy storage system are greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to a marine energy storage system and a charging method thereof. BACKGROUND

[0002] With the maturity of electric propulsion technology, all-electric ships have become the main direction of future ship design. Under this background, the marine energy storage system as an important part of modern ship design has gradually developed from auxiliary load power supply to multi-type ship load power supply, especially as an important part of the ship power system and cooperates with various ship main / auxiliary machines to improve the economic / environmental characteristics of the ship under the premise of meeting various load demands of the ship. However, the existing marine energy storage system usually follows the architecture of the land energy storage system, which is not optimized for the actual use environment of the ship, resulting in poor reliability of the ship energy storage system. SUMMARY

[0003] In view of the deficiencies of the prior art, the present application provides a marine energy storage system and a charging method thereof, aiming to solve the technical problem of poor reliability of the ship energy storage system in the prior art.

[0004] To solve the above problems, in a first aspect, the present application provides a charging method of a marine energy storage system, the marine energy storage system comprising a plurality of power supply branches and a first high-voltage box, the plurality of power supply branches being connected in parallel, each power supply branch comprising at least one battery pack and a second high-voltage box, the first high-voltage box being provided with a charging and discharging interface, the first high-voltage box being electrically connected to the second high-voltage box; the charging method comprising:

[0005] receiving a charging instruction for charging the marine energy storage system;

[0006] obtaining a branch voltage of each power supply branch;

[0007] determining a power-on strategy of the power supply branch according to the branch voltage, and closing a charging switch in the second high-voltage box according to the power-on strategy to power on the power supply branch;

[0008] if all the power supply branches are powered on, closing a charging switch in the first high-voltage box to charge the battery pack in each power supply branch through the first high-voltage box.

[0009] In a second aspect, the present application also provides a marine energy storage system comprising a plurality of power supply branches and a first high-voltage box, the power supply branch comprising:

[0010] at least one battery pack;

[0011] a second high-voltage box, one end of the second high-voltage box being electrically connected to the battery pack;

[0012] The first high-voltage box is provided with a charging and discharging interface, one end of the charging and discharging interface is electrically connected to the other end of the second high-voltage box, and the other end of the charging and discharging interface is electrically connected to the marine power distribution system or / and the charging and discharging device.

[0013] The application provides a charging method of the marine energy storage system. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0015] Figure 1 The first schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 1.

[0016] Figure 2 The second schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 2.

[0017] Figure 3 The third schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 3.

[0018] Figure 4 The fourth schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 4.

[0019] Figure 5 The fifth schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 5.

[0020] Figure 6 The sixth schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 6.

[0021] Figure 7 The seventh schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 7.

[0022] Figure 8 The eighth schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 8.

[0023] Figure 9 The ninth schematic diagram of the marine energy storage system provided by the embodiment of the application is shown in FIG. 9.

[0024] Figure 10A flowchart of a charging method of a marine energy storage system is provided. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0026] It should be understood that when used in the specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0027] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clearly indicated by the context, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0028] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0029] In addition, in the present application, unless otherwise explicitly specified or limited in the embodiments, the terms "mounting", "connecting", "connecting" and "fixing" and the like appearing in the embodiments should be understood broadly, for example, the connection can be a fixed connection, or a detachable connection, or integrated, which can be understood, or can be a mechanical connection, an electrical connection, etc. Of course, it can also be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements, or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific implementation situation.

[0030] The embodiments of the present application provide a marine energy storage system and a charging method thereof.

[0031] For the convenience of understanding, the ship energy storage system is introduced first, and the charging method of the ship energy storage system is introduced in detail on the basis of the ship energy storage system. Among them, the ship energy storage system can be a three-level architecture energy storage system, or a two-level architecture energy storage system. When the ship energy storage system is a two-level architecture energy storage system, the ship energy storage system can include at least one power supply branch, and a second high-voltage box 100 can be arranged in the power supply branch; when the ship energy storage system is a three-level architecture energy storage system, the ship energy storage system can include at least one power supply branch and a first high-voltage box, and a second high-voltage box can be arranged in the power supply branch.

[0032] Please refer to Figure 1 , Figure 1 The first schematic diagram of the ship energy storage system provided by the embodiment of the application is shown in the figure. As Figure 1 shown, the application provides a ship energy storage system, which includes at least one power supply branch, and the power supply branch includes:

[0033] a second high-voltage box 100;

[0034] an energy storage device 200 electrically connected to the second high-voltage box 100;

[0035] Among them, the second high-voltage box 100 is provided with a charging and discharging interface, and the charging and discharging interface is electrically connected to the ship power distribution system or the charging and discharging device.

[0036] In this embodiment, the charging and discharging of the ship energy storage system are integrated into one interface, i.e. the charging and discharging interface, which can be arranged on the second high-voltage box 100. At the same time, the second high-voltage box 100 is also provided with a first interface 110 and a second interface 120, and the energy storage device 200 is provided with a battery positive electrode and a battery negative electrode, the battery positive electrode is electrically connected to the first interface 110, and the battery negative electrode is electrically connected to the second interface 120; the second high-voltage box 100 includes a first switch circuit 170 and a second switch circuit 180, and the charging and discharging interface includes a charging and discharging positive electrode 101 and a charging and discharging negative electrode 102, the first switch circuit 170 is arranged between the first interface 110 and the charging and discharging positive electrode, the second switch circuit 180 is arranged between the second interface 120 and the charging and discharging negative electrode, and the first switch circuit 170 and the second switch circuit 180 are both provided with a switch for controlling the on-off of the main loop of the power supply branch, which can be a relay.

[0037] The ship can use the ship energy storage system mentioned in the above embodiment, when it is necessary to charge the above-mentioned ship energy storage system, it is necessary to separate the above-mentioned ship energy storage system from the ship, i.e. to separate the charging and discharging interface from the ship power distribution system, and to be electrically connected with the charging and discharging device, so as to realize the charging of the ship energy storage system.

[0038] When the ship energy storage system is separated from the ship and electrically connected with the charging and discharging device, the second switch circuit 180 can be first turned on, and then the first switch circuit 170 is turned on, so as to complete the power-on of the power supply branch. After the power-on of the power supply branch is completed, the battery pack 201 in the power supply branch can be charged.

[0039] Please refer to Figure 2 , Figure 2 The second schematic block diagram of the ship energy storage system provided by the embodiment of the application is shown in the figure. As shown in Figure 2 The application provides a ship energy storage system, which comprises at least one power supply branch, and the power supply branch comprises:

[0040] The second high-voltage box 100 is provided with a first interface 110 and a second interface 120.

[0041] The energy storage device 200 is provided with a battery positive electrode and a battery negative electrode, the battery positive electrode is electrically connected with the first interface 110, and the battery negative electrode is electrically connected with the second interface 120.

[0042] The second high-voltage box 100 is further provided with a charging and discharging interface, the charging and discharging interface comprises a charging interface 160 and a discharging interface 150, the charging interface 160 is electrically connected with the charging and discharging device, and the discharging interface 150 is electrically connected with the ship power distribution system.

[0043] In the embodiment, the ship energy storage system can be a ship container type energy storage system, which comprises at least one power supply branch, and the power supply branch is provided with the second high-voltage box 100 and the energy storage device 200. The second high-voltage box 100 is separately provided with the charging interface 160 and the discharging interface 150. The charging interface 160 is electrically connected with the charging and discharging device to charge the power supply branch of the energy storage system. The discharging interface 150 is electrically connected with the ship power distribution system to distribute the electric energy output by the power supply branch and supply the ship, so as to realize better independent control and protection of the battery charging and discharging process and greatly improve the safety and reliability of the ship energy storage system.

[0044] Meanwhile, the ship energy storage system provided by the application can comprise a plurality of power supply branches, each of which is provided with the second high-voltage box 100 and the energy storage device 200. The second high-voltage box 100 is separately provided with the charging interface 160 and the discharging interface 150. After being connected in parallel, the plurality of charging interfaces 160 on each second high-voltage box 100 can be integrated into one interface for charging, and the plurality of discharging interfaces 150 on each second high-voltage box 100 can be integrated into one interface for discharging.

[0045] Specifically, the marine energy storage system mentioned in the present application is a two-level architecture energy storage system, which can also be extended to a three-level architecture energy storage system. When it is extended to a three-level architecture energy storage system, a busbar cabinet can be connected at the rear end of the second high-voltage box 100, and the circuit inside the busbar cabinet can be designed similar to the circuit inside the second high-voltage box 100, thereby realizing a three-level architecture marine energy storage system.

[0046] The energy storage device 200 mentioned in the present application can include a plurality of battery packs 201, which are connected in series to form a battery cluster of the marine energy storage system. By arranging a plurality of battery packs 201 in each power supply branch, and connecting each battery pack 201 in series while also connecting a fuse or / and a relay in series, the voltage of the power supply branch can be increased, and the safety performance of the power supply branch can be enhanced. In addition, when the energy storage device 200 includes a plurality of battery packs 201, the plurality of battery packs 201 can also be connected in parallel to form a cluster of batteries of the marine energy storage system.

[0047] Meanwhile, each battery pack 201 can also include a fuse and at least one cell connected in series, respectively connected to the input and output terminals of the battery pack 201, or each battery pack 201 can include at least one fuse and at least one cell connected in series one by one, respectively connected to the input and output terminals to realize parallel connection, so that when a short circuit occurs in the battery pack 201, the second fuse can timely cut off the circuit where the battery pack 201 is located, to ensure the safety of the battery pack 201.

[0048] The marine energy storage system provided by the present application includes at least one power supply branch, which includes a second high-voltage box 100 and an energy storage device 200. The high-voltage box 100 is provided with a first interface 110, a second interface 120, a charging interface 160 and a discharging interface 150. The energy storage device 200 is provided with a battery positive electrode and a battery negative electrode. The battery positive electrode is electrically connected to the first interface 110, and the battery negative electrode is electrically connected to the second interface 120. The charging interface 160 is electrically connected to the charging and discharging device, and the discharging interface 150 is electrically connected to the marine power distribution system. Thus, the charging interface 160 and the discharging interface 150 of the marine energy storage system are separated, which can better realize independent control and protection of the battery charging and discharging process, and can avoid separating the marine energy storage system from the ship when charging the marine energy storage system, greatly improving the safety, reliability and practicability of the marine energy storage system.

[0049] In some embodiments, as Figure 3As shown, the second high-voltage box 100 includes the first switch circuit 170 and the second switch circuit 180, the charging interface 160 includes the charging positive electrode 161 and the charging negative electrode 162, and the discharging interface 150 includes the discharging positive electrode 151 and the discharging negative electrode 152; one end of the first switch circuit 170 is electrically connected to the first interface 110, and the other end of the first switch circuit 170 is respectively electrically connected to the charging positive electrode 161 and the discharging positive electrode 151; one end of the second switch circuit 180 is electrically connected to the second interface 120, and the other end of the second switch circuit 180 is respectively electrically connected to the charging negative electrode 162 and the discharging negative electrode 152.

[0050] In the embodiment, by arranging the first switch circuit 170 and the second switch circuit 180 in the first high-voltage box 100, the discharging positive electrode 151 of the discharging interface 150 and the charging positive electrode 161 of the charging interface 160 are both electrically connected to the first interface 110 through the first switch circuit 170 to realize electrical connection with the positive electrode of the battery of the energy storage device 200; the discharging negative electrode 152 of the discharging interface 150 and the charging negative electrode 162 of the charging interface 160 are both electrically connected to the second interface 120 through the second switch circuit 180 to realize electrical connection with the negative electrode of the battery of the energy storage device 200, so that when the marine energy storage system needs to be discharged, the passage between the charging positive electrode 161 and the first interface 110 and the passage between the charging negative electrode 162 and the second interface 120 are respectively disconnected through the first switch circuit 170 and the second switch circuit 180 to ensure normal discharge of the marine energy storage system; when the marine energy storage system needs to be charged, the passage between the discharging positive electrode 151 and the first interface 110 and the passage between the discharging negative electrode 152 and the second interface 120 are respectively disconnected through the first switch circuit 170 and the second switch circuit 180 to ensure normal charging of the marine energy storage system, thereby better realizing independent control and protection of the battery charging and discharging process and greatly improving the safety and reliability of the marine energy storage system.

[0051] Further, in some embodiments, as shown in FIG. 2, the first switch circuit 170 includes the first discharging switch 171 and the first charging switch 172; one end of the first discharging switch 171 and one end of the first charging switch 172 are both electrically connected to the first interface 110, the other end of the first discharging switch 171 is electrically connected to the discharging positive electrode 151, and the other end of the first charging switch 172 is electrically connected to the charging positive electrode 161. Figure 3

[0052] In the embodiment, the on-off of the first discharging switch 171 and the first charging switch 172 can be controlled by the battery management system of the marine energy storage system, and the first discharging switch 171 and the first charging switch 172 can both be relays.

[0053] ​The battery management system (BMS) is responsible for the charging and discharging management, status monitoring and analysis, power management, and protection functions of the batteries in marine energy storage systems. Specifically, the BMS can systematically manage and prevent overcharging, over-discharging, and overheating of the batteries in marine energy storage systems, thereby improving the battery performance and lifespan of the marine energy storage system.

[0054] Meanwhile, in marine energy storage systems, battery management systems typically include domain management units, cluster management units, module management units, and safety modules, enabling communication with the integrated control system for more efficient battery management. Furthermore, battery management systems can adopt a modular design, allowing for expansion based on battery configuration to adapt to different application scenarios.

[0055] Furthermore, in some embodiments, such as Figure 3 As shown, the second switching circuit 180 includes a second discharge switch 181 and a second charging switch 182; wherein, one end of the second discharge switch 181 and one end of the second charging switch 182 are electrically connected to the second interface 120, the other end of the second discharge switch 181 is electrically connected to the discharge negative terminal 152, and the other end of the second charging switch 182 is electrically connected to the charging negative terminal 162.

[0056] In this embodiment, the switching on and off of the second discharge switch 181 and the second charging switch 182 can both be controlled by the battery management system of the marine energy storage system, and both the second discharge switch 181 and the second charging switch 182 can be relays.

[0057] In addition, the first discharge switch 171, the second discharge switch 181, the first charging switch 172 and the second charging switch 182 can also be controlled by the ship management system. The on / off control method of the first discharge switch 171, the second discharge switch 181, the first charging switch 172 and the second charging switch 182 mentioned in this application can be selected according to the actual application, and this application does not make specific limitations.

[0058] In some embodiments, such as Figure 4 As shown, the second high-voltage box 100 also includes an equalization circuit 190; wherein, one end of the equalization circuit 190 is electrically connected to the first interface 110, and the other end of the equalization circuit 190 is electrically connected to the discharge positive terminal 151 and / or the charging positive terminal 161.

[0059] Because the internal resistance of each cell in a marine energy storage system varies, and the differences become even more pronounced after the cells are integrated into a battery cluster, the marine energy storage system needs to balance the batteries on each power supply branch before discharging to ensure voltage consistency between the power supply branches.

[0060] In this embodiment, an equalization circuit 190 can be provided between the first interface 110 and the discharge positive terminal 151. This allows the marine energy storage system to be balanced when it needs to discharge, ensuring voltage consistency between the various power supply branches. It also helps prevent inrush currents during charging and discharging. Specifically, when a power supply branch is powered on, the main negative switch (fourth switch 520) in the first high-voltage box 20 is first closed, then the equalization circuit 190 is turned on. After a preset time, the main positive switch (third switch 510) in the first high-voltage box 20 is closed, and then the equalization circuit 190 is turned off. This significantly improves the startup performance and safety of the marine energy storage system.

[0061] Furthermore, in some embodiments, such as Figure 4 As shown, the equalization circuit 190 includes an equalization switch 191 and an equalization resistor 192; wherein, one end of the equalization switch 191 is electrically connected to the first interface 110, the other end of the equalization switch 191 is electrically connected to one end of the equalization resistor 192, and the other end of the equalization resistor 192 is electrically connected to the discharge positive terminal 151.

[0062] In this embodiment, the switching on and off of the equalization switch 191 can be controlled by the battery management system, and the equalization switch 191 can be a relay. Alternatively, the switching on and off of the equalization switch 191 can also be controlled by the ship management system. The switching control of the equalization switch 191 can be selected according to the actual application, and this application does not impose specific limitations.

[0063] In some embodiments, the energy storage device 200 and the second high-voltage box 100 communicate with each other via a communication interface.

[0064] In this embodiment, the energy storage device 200 may include multiple battery packs 201, each of which may be equipped with a communication interface. The communication interfaces between the battery packs 201 can be electrically connected for communication. Simultaneously, the second high-voltage box 100 may also be equipped with a communication interface. The communication interfaces between the battery packs 201 and the second high-voltage box 100 can be electrically connected for communication. Therefore, the battery management system or the ship management system can manage the second high-voltage box 100 and the battery packs 201 through the communication interfaces of the battery packs 201 and the second high-voltage box 100. This allows for better independent control and protection of the battery charging and discharging process, greatly improving the safety and reliability of the marine energy storage system.

[0065] In some embodiments, the charging and discharging device is a charger or a charging pile.

[0066] Specifically, the charger is a device for providing power to the battery, which adopts high-frequency power supply technology and uses advanced intelligent dynamic adjustment charging technology, and has the characteristics of high charging efficiency, simple operation, light weight, small size, etc. The charger is widely used in various fields, including electric vehicles, electric motorcycles, electric forklifts, etc. The charger mentioned in the present application is mainly used in the field of ships, and can be installed on the ship. The charging pile is an important infrastructure for providing power to electric vehicles, and its function is similar to that of the fuel dispenser at the gas station. The charging pile mentioned in the present application is mainly used to provide power for the ship energy storage system.

[0067] In some embodiments, the discharging interface 150 is electrically connected to the marine power distribution system, which includes a DC / AC converter or an energy storage converter or a DC power distribution panel.

[0068] The marine power distribution system can be part of the electrical system of the ship, and the power distribution panel in the marine power distribution system can be a main power distribution panel, an emergency power distribution panel, etc. Among them, the marine main power distribution panel can be suitable for various types of ship power stations, and is used to control, monitor and protect the generator set and the distribution network.

[0069] In the present embodiment, the DC / AC converter, the energy storage converter and the DC power distribution panel can be provided in the marine power distribution system. Among them, the DC / AC converter, also known as an inverter, is a device that converts direct current (DC) to alternating current (AC). The DC / AC converter mainly realizes the conversion of direct current to alternating current through power semiconductor devices (such as IGBT or MOSFET). The energy storage converter can control the charging and discharging process of the power supply branch and perform AC / DC conversion, and can also directly power AC loads in the absence of a power grid. The DC power distribution panel is a device for distributing and managing DC power, and is widely used in various industries, ships and new energy fields.

[0070] In some embodiments, in order to improve the safety performance of the marine energy storage system, as shown in Figure 5 The present application also provides a marine energy storage system, which includes at least one power supply branch 10 and a first high-voltage box 20; the power supply branch 10 includes:

[0071] The energy storage device 200 is provided with a positive electrode and a negative electrode;

[0072] The second high-voltage box 100 is provided with a first interface 110, a second interface 120, a third interface 130 and a fourth interface 140, the first interface 110 is electrically connected to the positive electrode, and the second interface 120 is electrically connected to the negative electrode;

[0073] The first high-voltage box 20 comprises a third switch circuit 300, a first end of the third switch circuit 300 is electrically connected to the third interface 130, a second end of the third switch circuit 300 is electrically connected to the fourth interface 140, and a third end and a fourth end of the third switch circuit 300 are both electrically connected to the marine power distribution system.

[0074] In the embodiment, the marine energy storage system can be a marine container-type energy storage system, which comprises at least one power supply branch 10 and a first high-voltage box 20, the power supply branch 10 is provided with a second high-voltage box 100 and an energy storage device 200, the energy storage device 200 is provided with a battery positive electrode and a battery negative electrode, the high-voltage box is provided with a first interface 110, a second interface 120, a third interface 130 and a fourth interface 140, the first interface 110 is electrically connected to the battery positive electrode, the second interface 120 is electrically connected to the battery negative electrode, and the second high-voltage box 100 and the marine power distribution system are provided with a third switch circuit 300, which not only realizes the monitoring and management of the high-voltage circuit of the marine energy storage system, but also realizes the three-level protection of the energy storage system, thereby improving the safety and reliability of the marine energy storage system.

[0075] The first high-voltage box 20 can be a group high-voltage box, and the second high-voltage box 100 can be a cluster high-voltage box. One power supply branch 10 can be understood as one battery cluster. The group high-voltage box generally refers to a high-voltage box used when multiple battery clusters are connected in parallel to form a battery stack. The group high-voltage box can be composed of high-voltage power boards (such as DC / DC converters, pre-charging modules, fuses, sensors, high-voltage acquisition and communication modules), main switches and contactors, etc. The main function of the group high-voltage box is to aggregate the outputs of multiple battery clusters and provide a unified high-voltage output interface. The group high-voltage box is commonly used in large-scale energy storage systems, such as energy storage systems above 6MWh, which not only require different grouping methods, but also put forward higher requirements on the battery management system. The group high-voltage box can support the parallel connection of multiple battery clusters, thereby improving the overall efficiency and reliability of the system. At the same time, the group high-voltage box usually has a large capacity and a higher voltage level, which is suitable for large-scale energy storage applications. Its design needs to consider the parallel connection requirements of multiple battery clusters, as well as corresponding heat dissipation and protection measures. In addition, the group high-voltage box also needs to have flexible customization design capabilities to adapt to different installation and wiring requirements.

[0076] The cluster high-voltage box is mainly used for managing the power loop of the battery cluster. The cluster high-voltage box can be integrated with elements such as circuit breakers, contactors, fuses, shunts, pre-charge circuits, switching power supplies, and battery cluster management modules, which collectively form a complete battery cluster management system responsible for functions such as voltage collection, current collection, temperature monitoring, and data communication of the battery cluster. The cluster high-voltage box is usually used to connect a single or multiple battery clusters and connect them with energy storage converters or other control devices. For example, in a large energy storage power station, a cluster high-voltage box can connect two clusters of batteries to achieve a two-in-two-out configuration. In addition, the cluster high-voltage box is also suitable for various energy storage scenarios, including source, grid, load, and shared energy storage. At the same time, the design of the cluster high-voltage box needs to consider factors such as explosion-proof, fireproof, and theft-proof to ensure the safe operation of the system. Its internal structure is complex and integrates multiple electronic controllers and sensors to achieve comprehensive management of the battery cluster.

[0077] The marine energy storage system provided by the application comprises at least one power supply branch 10 and a first high-voltage box 20. The power supply branch 10 comprises an energy storage device 200 and a second high-voltage box 100. The energy storage device 200 is provided with a battery positive electrode and a battery negative electrode. The second high-voltage box 100 is provided with a first interface 110, a second interface 120, a third interface 130, and a fourth interface 140. The first interface 110 is electrically connected to the battery positive electrode, and the second interface 120 is electrically connected to the battery negative electrode. The first high-voltage box 20 comprises a third switching circuit 300. The first end of the third switching circuit 300 is electrically connected to the third interface 130, the second end of the third switching circuit 300 is electrically connected to the fourth interface 140, and the third end and the fourth end of the third switching circuit 300 are both electrically connected to the marine power distribution system. Therefore, not only can the first high-voltage box 20 be used to monitor and manage the high-voltage circuit of the marine energy storage system, but also the third switching circuit 300 in the first high-voltage box 20 can be used to implement three-level protection of the energy storage system, greatly improving the safety and reliability of the marine energy storage system.

[0078] In some embodiments, as shown in Figure 6 and Figure 7 The third switching circuit 300 comprises a first switch 310 and a second switch. One end of the first switch 310 is electrically connected to the third interface 130, and the other end of the first switch 310 is electrically connected to the marine power distribution system. One end of the second switch is electrically connected to the fourth interface 140, and the other end of the second switch is electrically connected to the marine power distribution system.

[0079] In this embodiment, the on-off of the first switch 310 and the second switch 320 can be controlled by the battery management system of the marine energy storage system, and the first switch 310 and the second switch 320 can both be relays.

[0080] The battery management system is responsible for the charge and discharge management, state monitoring and analysis, power management, and protection of the batteries of the marine energy storage system. Specifically, through systematic management, the battery management system can avoid overcharging, over-discharging, and over-temperature of the batteries of the marine energy storage system, thereby improving the performance and service life of the batteries of the marine energy storage system.

[0081] Meanwhile, in the marine energy storage system, the battery management system usually includes domain management units, cluster management units, module management units, and safety modules, and can communicate with the integrated control system to achieve more efficient battery management. In addition, the battery management system can also adopt modular design and can be expanded according to the composition of the batteries to adapt to different application scenarios.

[0082] In some embodiments, the third switch circuit 300 includes an isolating switch; wherein the first end of the isolating switch is electrically connected to the third interface 130, the second end of the isolating switch is electrically connected to the fourth interface 140, and the third end and the fourth end of the isolating switch are both electrically connected to the marine power distribution system.

[0083] Specifically, the isolating switch is a kind of switch equipment used in electrical system to ensure the safety isolation of circuit, its main function is to physically disconnect the circuit to ensure that the circuit is completely powered off during maintenance and repair, to prevent electric shock or other dangers. When the isolating switch is in the open position, there is a specified insulation distance and obvious disconnect mark between the contacts; when the isolating switch is in the closed position, it can carry the current under normal circuit conditions and the current under abnormal conditions (such as short circuit) within a specified time. In this embodiment, the on-off of the isolating switch can be controlled by the battery management system of the marine energy storage system, which can replace the first switch 310 and the second switch 320 mentioned in the above embodiment.

[0084] In some embodiments, as shown in Figure 7 the first high-voltage box 20 further includes a pre-charging circuit 400; wherein one end of the pre-charging circuit 400 is respectively electrically connected to the third interface 130 and the first end of the third switch circuit 300, and the other end of the pre-charging circuit 400 is respectively electrically connected to the marine power distribution system and the second end of the third switch circuit 300.

[0085] In this embodiment, the pre-charging circuit 400 can avoid the occurrence of inrush current when the marine energy storage system is charging and discharging. Specifically, after the power supply branch 10 is powered on, pre-charging is performed through the pre-charging circuit 400, after pre-charging is completed, the third switch circuit 300 in the first high-voltage box 20 is turned on, and the pre-charging circuit 400 is disconnected, thereby significantly improving the starting performance and safety of the marine energy storage system.

[0086] Further, in some embodiments, as shown in Figure 7As shown, the pre-charge circuit 400 includes a pre-charge switch 410 and a pre-charge resistor 420; one end of the pre-charge switch 410 is electrically connected to the third interface 130 and the first end of the third switch circuit 300 respectively, the other end of the pre-charge switch 410 is electrically connected to one end of the pre-charge resistor 420, and the other end of the pre-charge resistor 420 is electrically connected to the marine power distribution system and the second end of the third switch circuit 300 respectively.

[0087] Specifically, after the power supply branch 10 is powered on, the main negative switch in the third switch circuit 300, i.e. the second switch 320, can be closed first, then the pre-charge switch 410 is closed, after a preset time, i.e. after the pre-charge is completed, the main positive switch in the third switch circuit 300, i.e. the first switch 310, is closed, and then the pre-charge switch 410 is opened, so as to realize the normal power-on of the marine energy storage system.

[0088] In some embodiments, the first high-voltage box 20 is provided with a charge-discharge interface, and the charge-discharge interface includes a charge-discharge positive electrode and a charge-discharge negative electrode; one end of the charge-discharge positive electrode is electrically connected to the third end of the third switch circuit 300 and the other end of the pre-charge circuit 400 respectively, and the other end of the charge-discharge positive electrode is electrically connected to the marine power distribution system; one end of the charge-discharge negative electrode is electrically connected to the fourth end of the third switch circuit 300, and the other end of the charge-discharge negative electrode is electrically connected to the marine power distribution system.

[0089] In some embodiments, as shown in Figure 8 and Figure 9 , the second high-voltage box 100 includes a fourth switch circuit 500; the first end of the fourth switch circuit 500 is electrically connected to the first interface 110, the second end of the fourth switch circuit 500 is electrically connected to the second interface 120, the third end of the fourth switch circuit 500 is electrically connected to the third interface 130, and the fourth end of the fourth switch circuit 500 is electrically connected to the fourth interface 140.

[0090] In this embodiment, the second high-voltage box 100 uses the fourth switch circuit 500 to control the on-off of the power supply branch 10 where the second high-voltage box 100 is located. When it is needed to disconnect the main loop of the power supply branch 10, the fourth switch circuit 500 can be opened to achieve this; when it is needed to conduct the main loop of the power supply branch 10, the fourth switch circuit 500 can be conducted to achieve this.

[0091] Further, in some embodiments, as shown in Figure 8 and Figure 9 , the fourth switch circuit 500 includes a third switch 510 and a fourth switch 520; one end of the third switch 510 is electrically connected to the first interface 110, and the other end of the third switch 510 is electrically connected to the third interface 130; one end of the fourth switch 520 is electrically connected to the second interface 120, and the other end of the fourth switch 520 is electrically connected to the fourth interface 140.

[0092] In the embodiment, the on-off of the third switch 510 and the fourth switch 520 can be controlled by the battery management system of the marine energy storage system, and the third switch 510 and the fourth switch 520 can be relays.

[0093] In addition, the first switch 310, the second switch 320, the third switch 510, and the fourth switch 520 can also be controlled by the ship management system, and the on-off control mode of the first switch 310, the second switch 320, the third switch 510, and the fourth switch 520 mentioned in the application can be selected according to actual application, which is not limited in the application.

[0094] In some embodiments, as shown in Figure 9 The second high-voltage box 100 further includes an equalization circuit 190; one end of the equalization circuit 190 is electrically connected to the first interface 110 and the first end of the fourth switch circuit 500, respectively, and the other end of the equalization circuit 190 is electrically connected to the third interface 130 and the second end of the fourth switch circuit 500, respectively.

[0095] Due to the difference in voltage resistance of each cell in the marine energy storage system, the difference after the cell integration into a battery cluster is more significant, so the marine energy storage system needs to balance the batteries on each power supply branch 10 before discharging to ensure the voltage consistency between the power supply branches 10.

[0096] In the embodiment, an equalization circuit 190 can be arranged between the battery positive electrode and the discharge positive electrode 151, so that when the marine energy storage system needs to discharge, the equalization circuit 190 is used for equalization to ensure the voltage consistency between the power supply branches 10. At the same time, it can also avoid the impact current when the marine energy storage system is charging and discharging. Specifically, when the power supply branch 10 is powered on, the main negative switch in the second high-voltage box 100, i.e., the fourth switch 520, can be closed first, then the equalization circuit 190 is turned on, after a preset time, the main positive switch in the second high-voltage box 100, i.e., the third switch 510, is closed, and then the equalization circuit 190 is turned off, thereby significantly improving the starting performance and safety of the marine energy storage system.

[0097] Further, in some embodiments, as shown in Figure 9 The equalization circuit 190 includes an equalization switch 191 and an equalization resistor 192; one end of the equalization switch 191 is electrically connected to the first interface 110 and the first end of the fourth switch circuit 500, respectively, the other end of the equalization switch 191 is electrically connected to one end of the equalization resistor 192, and the other end of the equalization resistor 192 is electrically connected to the third interface 130 and the second end of the fourth switch circuit 500, respectively.

[0098] In the embodiment, the on-off of the equalization switch 191 can be controlled by the battery management system, and the equalization switch 191 can be a relay. Meanwhile, the on-off of the equalization switch 191 can also be controlled by the ship management system, and the on-off control of the equalization switch 191 can be selected according to actual application, which is not limited in the present application.

[0099] In some embodiments, the energy storage device 200, the first high-voltage box 20 and the second high-voltage box 100 are in communication through respective communication interfaces.

[0100] In the embodiment, the energy storage device 200 can include a plurality of battery packs 201, and each battery pack 201 can be provided with a communication interface. The communication interfaces between the battery packs 201 can be electrically connected for communication. Meanwhile, the first high-voltage box 20 and the second high-voltage box 100 are each provided with a communication interface. The communication interfaces between the battery packs 201 and the second high-voltage box 100 and between the first high-voltage box 20 and the second high-voltage box 100 can also be electrically connected for communication. Therefore, the battery management system or the ship management system can manage the first high-voltage box 20, the second high-voltage box 100 and the battery packs 201 through the communication interfaces of the battery packs 201 and the communication interfaces of the high-voltage boxes, greatly improving the safety and reliability of the marine energy storage system.

[0101] In some embodiments, the third end and the fourth end of the third switch circuit 300 are electrically connected to a marine power distribution system, and the marine power distribution system includes a DC / AC converter or an energy storage converter or a direct current distribution panel.

[0102] In the embodiment, the marine power distribution system can be part of the electrical system of the ship, and the power distribution panel in the marine power distribution system can be a main power distribution panel, an emergency power distribution panel or the like. The marine main power distribution panel can be suitable for various ship power stations and used to control, monitor and protect the generator set and the distribution network.

[0103] The DC / AC converter, the energy storage converter and the direct current distribution panel can be provided in the marine power distribution system. The DC / AC converter, also known as an inverter, is a device that converts direct current (DC) into alternating current (AC). The DC / AC converter mainly converts DC to AC through power semiconductor devices such as IGBT or MOSFET. The energy storage converter can control the charging and discharging process of the power supply branch 10 and convert AC and DC. It can also directly power AC loads without power grid. The direct current distribution panel is a device for distributing and managing direct current energy, widely used in various industries, ships and new energy fields.

[0104] It can be understood that the ship energy storage system provided in the above embodiments is only an example, and the ship energy storage system described in the embodiments of the present application is used to more clearly illustrate the technical solutions of the embodiments of the present application, and does not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art can know that with the evolution of the system and the emergence of new business scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems. The following will be described in detail.

[0105] It should be noted that the sequence of the following embodiment descriptions does not constitute a limitation on the preferred sequence of the embodiments. The charging method of the ship energy storage system will be described in detail below. At the same time, the charging method of the ship energy storage system provided by the present application can be executed by the battery management system.

[0106] Please refer to Figure 10 , Figure 10 The flowchart of the charging method of the ship energy storage system provided by the embodiments of the present application is shown in FIG. 1. As shown in FIG. 1, the method comprises steps S110-S140. Figure 10

[0107] S110, receiving a charging instruction for charging the ship energy storage system.

[0108] In the present embodiment, the charging instruction is instruction information for requesting to charge the ship energy storage system, and the charging instruction can be issued by the ship management system, the automated manifest system, the planned maintenance system, the ship energy management system, etc. to the battery management system of the ship energy storage system.

[0109] In some embodiments, after receiving the charging instruction for charging the ship energy storage system, and before obtaining the branch voltage of each power supply branch, further comprising: obtaining charging information of the ship energy storage system; and determining whether the charge-discharge interface has a separate charging interface and a discharging interface according to the charging information; if the charge-discharge interface has a separate charging interface and a discharging interface, obtaining the on-off information of the discharging switch corresponding to the discharging interface; if the on-off information shows that the discharging switch is in a closed state, open the discharging switch; close the charging switch corresponding to the charging interface, and charge the battery pack in the power supply branch where the charging switch is located.

[0110] ​In this embodiment, the charging information is the configuration information of the marine energy storage system. Since the charging and discharging interface of the marine energy storage system can be the same or different, the charging and discharging interface of the marine energy storage system includes two independent charging interfaces and discharging interfaces. Therefore, after receiving the charging instruction for charging the marine energy storage system, the battery management system needs to determine whether the charging and discharging interface has a separate charging interface and discharging interface according to the charging information of the marine energy storage system. If the charging and discharging interface has a separate charging interface and discharging interface, the charging and discharging interface of the marine energy storage system can be charged by using the strategy of different charging and discharging interfaces. If the charging and discharging interface does not have a separate charging interface and discharging interface, the charging and discharging interface of the marine energy storage system can be charged by using the strategy of the same charging and discharging interface. Wherein, the charging and discharging interface of the marine energy storage system includes a separate charging interface and discharging interface, and the charging and discharging interface of the marine energy storage system is integrated into one interface.

[0111] At the same time, after determining whether the charging and discharging interface has a separate charging interface and discharging interface, the charging device connected to the charging and discharging interface can be on the ship, and at this time, the ship energy storage system can still be supplying power to the ship. Therefore, after determining whether the charging and discharging interface has a separate charging interface and discharging interface, the application also needs to determine whether the ship energy storage system is still supplying power to the ship. If the on-off information shows that the discharging switch is closed, the discharging switch needs to be opened at this time, and then the charging switch corresponding to the discharging interface is closed to supply power to the ship energy storage system.

[0112] Wherein, the discharging switch can be the first discharging switch of the first switch circuit and the second discharging switch of the second switch circuit in the second high-voltage box. Specifically, if the first discharging switch and the second discharging switch are in a closed state, the first discharging switch and the second discharging switch need to be opened in sequence to ensure that the marine power distribution system and the marine energy storage system are in a disconnected state.

[0113] In addition, after the marine energy storage system and the marine power distribution system are in a disconnected state, the charging switch in the second high-voltage box can be closed at this time to charge the power supply branch. Wherein, the charging switch can be the first charging switch of the first switch circuit and the second charging switch of the second switch circuit in the second high-voltage box. Specifically, after the marine energy storage system and the marine power distribution system are in a disconnected state, the second charging switch and the first charging switch can be closed in sequence.

[0114] S120, acquiring the branch voltage of each power supply branch.

[0115] Specifically, the application can obtain the branch voltage of each power supply branch in the marine energy storage system, and then sort the power supply branches in the marine energy storage system from low to high according to the voltage, and sequentially perform power-on balancing from low to high, so as to avoid the problem of poor voltage consistency of each power supply branch in the charging process.

[0116] In some embodiments, before obtaining the branch voltage of each power supply branch, the method further comprises: obtaining charging information of the marine energy storage system; if the charging information is preset first information, determining whether the communication connection between the charge-discharge interface and the charging pile is successful; if the communication connection between the charge-discharge interface and the charging pile is successful, performing fault detection on the marine energy storage system to obtain fault detection information of the marine energy storage system.

[0117] Specifically, the first information can be a charging connection confirmation signal. Since the marine energy storage system may use a charging pile to charge during charging, the battery management system needs to confirm whether the charging pile is used for charging after receiving the charging instruction for charging the marine energy storage system. If the charging pile is used for charging, it is necessary to determine whether the charging connection confirmation signal, i.e. the first information, sent by the charging pile to the battery management system of the marine energy storage system at the charge-discharge interface is received. If the charging connection confirmation signal sent by the charging pile is received, it can be determined whether the communication connection between the charge-discharge interface and the charging pile is successful. At this time, the battery management system can run a self-checking program to perform fault detection on the marine energy storage system, so as to obtain information about whether the marine energy storage system has a fault.

[0118] The charging connection confirmation signal can be a CC2 signal. After the charging pile is electrically connected with the charging interface of the marine energy storage system, the battery management system of the marine energy storage system can detect the CC2 signal and be awakened. After the battery management system is awakened by the CC2 signal, it can run a self-checking program to perform fault detection on the marine energy storage system, so as to obtain information about whether the marine energy storage system has a fault.

[0119] In some embodiments, after obtaining the charging information of the marine energy storage system, the method further comprises: if the charging information is preset second information, determining whether the charging instruction is valid; if the charging instruction is valid, determining whether the marine energy storage system is successfully connected in communication with the ship management system; if the marine energy storage system is successfully connected in communication with the ship management system, performing fault detection on the marine energy storage system to obtain fault detection information.

[0120] In the embodiment, the second information is a charging connection confirmation signal not existing in the charging information. When the battery management system does not detect the charging connection signal, that is, the second information exists in the charging information, it can be confirmed that the marine energy storage system is not charged by the charging pile, and it may be charged by the charging machine. Therefore, after the battery management system does not detect the charging connection signal, it needs to confirm whether the charging instruction sent by the ship management system to the battery management system is valid. If the charging instruction is valid, the battery management system is woken up and runs a self-checking program to detect faults of the marine energy storage system, so as to obtain information about whether the marine energy storage system has faults. If the charging instruction is invalid, the marine energy storage system needs to be charged and protected, and alarm information about charging failure is generated.

[0121] Meanwhile, before the battery management system runs the self-checking program, if the charging and discharging interface is not electrically connected to the charging pile but is electrically connected to the charging device, it is further needed to determine whether the battery management system is successfully connected in communication with the ship management system. If the communication connection is successful, the self-checking program can be run to detect faults of the marine energy storage system.

[0122] In some embodiments, after obtaining the charging information of the marine energy storage system, it further includes: if the charging information has preset third information, determining whether the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack; if the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack, detecting faults of the marine energy storage system to obtain fault detection information.

[0123] In the embodiment, after the battery management system does not detect the charging connection signal, it can also determine whether the marine energy storage system needs to be charged by determining whether the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack, that is, by determining the current direction at the charging and discharging interface. If the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack, it can be determined that the marine energy storage system needs to be charged, and then the battery management system is woken up and runs a self-checking program to detect faults of the marine energy storage system, so as to obtain information about whether the marine energy storage system has faults.

[0124] Meanwhile, after the charging instruction is invalid, the application can also determine whether the marine energy storage system needs to be charged by determining whether the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack. If the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack, it can be determined that the marine energy storage system needs to be charged, and then the battery management system is woken up and runs a self-checking program to detect faults of the marine energy storage system, so as to obtain information about whether the marine energy storage system has faults.

[0125] In some embodiments, before detecting faults of the marine energy storage system to obtain fault detection information of the marine energy storage system, it further includes: obtaining the current temperature of the battery pack.

[0126] Specifically, after determining that the marine energy storage system needs to be charged, the battery management system needs to obtain the current temperature of the battery pack in the marine energy storage system, and determine whether the current temperature of the battery pack meets the charging requirement, i.e., the current temperature of the battery pack is not less than the first temperature and not greater than the second temperature, at this time, the self-checking program can be run to detect the fault of the marine energy storage system; if the current temperature of the battery pack does not meet the charging requirement, i.e., the current temperature of the battery pack is less than the first temperature, the battery pack needs to be heated at this time, so that the temperature of the battery pack is not less than the first temperature and not greater than the second temperature; if the current temperature of the battery pack is greater than the second temperature, the battery pack needs to be cooled at this time, and after the temperature of the battery pack is not less than the first temperature and not greater than the second temperature, the self-checking program can be run to detect the fault of the marine energy storage system.

[0127] The first temperature can be a critical temperature for determining whether the marine energy storage system needs to be heated, and the second temperature can be a critical temperature for determining whether the marine energy storage system needs to be cooled. The first temperature and the second temperature can be determined according to the battery pack itself, which is not limited in the present application.

[0128] In some embodiments, after obtaining the current temperature of the battery pack, the method further includes: if the current temperature is less than the first temperature, generating a heating instruction for heating the battery pack; and after a preset first time, detecting the temperature of the battery pack again to determine whether the marine energy storage system has a heating fault.

[0129] In the present embodiment, when the current temperature of the battery pack in the marine energy storage system is less than the first temperature, it can be determined that the temperature of the battery pack is too low, at this time, the battery management system generates a heating instruction for heating the battery pack, the device for heating the battery pack in the marine energy storage system, such as a closed heating relay, is used to heat the battery pack, and after a preset first time, the temperature of the battery pack is detected, if the temperature of the battery pack is between the first temperature and the second temperature, the heating relay can be disconnected, and the self-checking program can be run to detect the fault of the marine energy storage system; if the temperature of the battery pack still does not reach the first temperature, it can be determined that the marine energy storage system has a heating fault, at this time, the heating relay needs to be disconnected, and the marine energy storage system needs to be charged, and an alarm information of charging failure is generated.

[0130] In addition, before the battery management system runs the self-checking program, if the charge-discharge interface of the ship energy storage system is not electrically connected to the charging pile but is electrically connected to the charging device, it is necessary to further determine whether the battery management system and the ship management system are successfully connected in communication. If the communication connection is successful, the self-checking program can be run to detect faults of the ship energy storage system.

[0131] In the embodiment, the power-on strategy is rule information for powering on each power supply branch of the ship energy storage system before the ship energy storage system is charged. For example, when there are multiple parallel power supply branches in the ship energy storage system, in order to ensure the consistency of the charging voltage of each power supply branch, the power supply branch with low voltage can be powered on first, and then the other power supply branches can be powered on in turn after the power supply branch with low voltage is powered on. When there are two power supply branches in the energy storage system, the power supply branch with low voltage can be powered on first, and then the other power supply branch can be powered on after the power supply branch with low voltage is powered on.

[0132] In the embodiment, the power-on strategy is rule information for powering on each power supply branch of the ship energy storage system before the ship energy storage system is charged. For example, when there are multiple parallel power supply branches in the ship energy storage system, in order to ensure the consistency of the charging voltage of each power supply branch, the power supply branch with low voltage can be powered on first, and then the other power supply branches can be powered on in turn after the power supply branch with low voltage is powered on. When there are two power supply branches in the energy storage system, the power supply branch with low voltage can be powered on first, and then the other power supply branch can be powered on after the power supply branch with low voltage is powered on.

[0133] In some embodiments, determining the power-on strategy of the power supply branch according to the branch voltage and closing the charging switch of the second high-voltage box according to the power-on strategy to power on the power supply branch, comprises: determining a first power supply branch with a first branch voltage and a second power supply branch with a second branch voltage from the ship energy storage system according to the branch voltage; wherein the first branch voltage is less than or equal to the second branch voltage; closing the charging switch of the second high-voltage box in the first power supply branch to power on the first power supply branch; obtaining the bus voltage of the ship energy storage system after the first power supply branch is powered on; generating a voltage difference between the second power supply branch and the bus of the ship energy storage system according to the second branch voltage and the bus voltage; and closing the charging switch of the second high-voltage box in the second power supply branch with the second voltage to power on the second power supply branch.

[0134] In the embodiment, after obtaining the branch voltage of each power supply branch in the ship energy storage system, at least the first power supply branch with the first branch voltage and the second power supply branch with the second branch voltage can be determined from the branch voltage, and then the size of the first branch voltage and the second branch voltage can be determined, such as the first branch voltage being less than the second branch voltage. At this time, the first power supply branch can be powered on first, and the second power supply branch can be powered on after the first branch voltage is powered on.

[0135] Meanwhile, after the first power supply branch is powered on, there is voltage on the bus of the marine energy storage system. At this time, if the charging switch of the second high-voltage box in the second power supply branch is directly closed, the voltage difference between the power supply branches may be too large. Therefore, after the first power supply branch is powered on, the charging switch of the second high-voltage box in the second power supply branch needs to be closed according to the voltage difference between the second power supply branch and the bus of the marine energy storage system, so as to realize power-on of the second power supply branch.

[0136] In some embodiments, the charging switch in the second high-voltage box includes a first charging switch and a second charging switch, and the second high-voltage box is further provided with an equalization switch in parallel with the first charging switch. Closing the charging switch of the second high-voltage box in the first power supply branch includes: sequentially closing the second charging switch and the equalization switch of the second high-voltage box in the first power supply branch; after a preset second time, closing the first charging switch, and after a preset third time, opening the equalization switch.

[0137] In the present embodiment, the first charging switch and the second charging switch can be a main positive relay and a main negative relay in the second high-voltage box, respectively. In order to avoid too large voltage difference in the power-on process of the first power supply branch, the second high-voltage box is further provided with an equalization switch in parallel with the main positive relay. When it is necessary to close the charging switch of the second high-voltage box in the first power supply branch, the main negative relay, i.e. the second charging switch, can be closed first, and then the equalization switch is closed. After a preset second time, the main positive relay, i.e. the first charging switch, is closed, and after a preset third time, the equalization switch is opened, so as to complete the power-on of the first power supply branch. The second time and the third time can be selected according to actual application, and the present application does not make specific limitation.

[0138] In some embodiments, closing the charging switch of the second high-voltage box in the second power supply branch according to the voltage difference includes: if the voltage difference is less than a preset first voltage, sequentially closing the second charging switch and the first charging switch of the second high-voltage box in the second power supply branch; if the voltage difference is greater than or equal to the first voltage and less than or equal to a preset second voltage, sequentially closing the second charging switch and the equalization switch of the second high-voltage box in the second power supply branch; after a preset fourth time, closing the first charging switch, and after a preset fifth time, opening the equalization switch; if the voltage difference is greater than the second voltage, generating a charging protection instruction of the marine energy storage system.

[0139] Specifically, in order to avoid that the power supply branch with high voltage has too large voltage difference between the branch voltage and the bus voltage in the power-on process, after determining the voltage difference between the second power supply branch and the bus of the marine energy storage system, the present application can balance through the equalization circuit of the second high-voltage box in the second power supply branch. The equalization circuit includes an equalization switch and an equalization resistor in series.

[0140] In the embodiment, if the voltage difference is less than a first voltage, such as 5V, the second charging switch and the first charging switch of the second high-voltage box in the second power supply branch are sequentially closed; if the voltage difference is greater than or equal to the first voltage and less than or equal to a second voltage, such as 20V, the second charging switch and the balancing switch of the second high-voltage box in the second power supply branch are sequentially closed; after a preset fourth time, the first charging switch is closed, and after a preset fifth time, the balancing switch is disconnected; if the voltage difference is greater than the second voltage, a charging protection instruction of the marine energy storage system is generated to perform charging protection on the marine energy storage system. The fourth time and the fifth time can be selected according to actual application, and the application does not make specific limitation.

[0141] In addition, there is also a possible case that after the fourth time, the voltage difference is still between the first voltage and the second voltage, at this time, the marine energy storage system may have a fault, and therefore all power supply branches of the marine energy storage system need to be powered off for charging protection. The fourth time can be 5h.

[0142] S140, if all the power supply branches are powered on, the charging switch in the first high-voltage box is closed to charge the battery pack in each power supply branch through the first high-voltage box.

[0143] Specifically, if the marine energy storage system is a three-level architecture energy storage system, the marine energy storage system has a first high-voltage box, when all the power supply branches in the marine energy storage system are powered on, the charging switch of the first high-voltage box in the marine energy storage system can be closed to make the marine energy storage system enter the charging stage; if the marine energy storage system is a two-level architecture energy storage system, when all the power supply branches in the marine energy storage system are powered on, the marine energy storage system does not have a first high-voltage box, when all the power supply branches in the marine energy storage system are powered on, the marine energy storage system directly enters the charging stage.

[0144] In some embodiments, the charging method of the marine energy storage system further includes: if the marine energy storage system in the charging state is abnormal, acquiring abnormal information of the marine energy storage system; if the abnormal information does not trigger the marine energy storage system to be powered off, determining whether to trigger the charging current of the marine energy storage system to be reduced; if the charging current of the marine energy storage system is triggered to be reduced, the marine energy storage system is charged by using a preset first current.

[0145] Specifically, when the marine energy storage system is in the formal charging stage, i.e., the first charging switch and the second charging switch in the second high-voltage box are in the closed state, the battery management system can monitor the voltage, current, temperature, SOC, SOH, internal resistance and other key parameters of the marine energy storage system. When an abnormality is detected in a key parameter of the marine energy storage system, abnormal information of the marine energy storage system can be obtained, and it can be determined whether to trigger the condition that the charging of the marine energy storage system needs to be stopped through the abnormal information. If the charging of the marine energy storage system does not need to be stopped, such as an abnormality in a certain power supply branch of the marine energy storage system, the main circuit of the power supply branch where the battery pack is located can be disconnected, and the charging current of the marine energy storage system can be adjusted, i.e., the other power supply branches that do not have abnormality continue to be charged. When adjusting the charging current of the marine energy storage system, the first current can be determined according to the number of power supply branches in the energy storage system and the number of power supply branches with abnormality, and the marine energy storage system can be charged according to the first current.

[0146] In addition, during the charging process of the marine energy storage system, the temperature of the battery pack during the charging process may be low due to the low water temperature of the area where the ship is located, which may cause the marine energy storage system to have an abnormality. At this time, the main circuit of the power supply branch where the battery pack is located can not be disconnected, and only the charging current of the marine energy storage system can be reduced.

[0147] In some embodiments, the charging method of the marine energy storage system further comprises: obtaining the single cell voltage of the battery cell in the battery pack when the marine energy storage system is in the charging state; if the single cell voltage is greater than or equal to a preset third voltage, the charging current of the marine energy storage system is adjusted to a preset second current; after a preset sixth time, the charging current of the marine energy storage system is adjusted to a preset third current; wherein the third current is less than the second current; after a preset seventh time, the charging current of the marine energy storage system is adjusted to a preset fourth current; wherein the fourth current is less than the third current.

[0148] Specifically, in order to avoid the voltage difference between the terminal voltages of each power supply branch of the marine energy storage system being too large after the charging is completed, at least one reduction of the charging current can be performed at the end of the charging of the marine energy storage system. The charging end can be understood as the SOH of the marine energy storage system reaching 80% or more, and the charging end can also be understood as the single cell voltage of the battery cell in the marine energy storage system being not less than a preset third voltage, such as 3.48V. It should be noted that the specific value of the charging end can be selected according to actual application, which is not limited herein.

[0149] In the embodiment, if the single cell voltage is greater than or equal to the preset third voltage, the charging current of the battery pack is reduced to the second current, and after the sixth time, the charging current of the marine energy storage system is reduced from the second current to the third current, and then after the seventh time, the charging current of the marine energy storage system is reduced from the third current to the fourth current, thereby avoiding that the voltage difference between the terminal voltages of each power supply branch is too large.

[0150] In some embodiments, after the charging current of the marine energy storage system is adjusted to the preset fourth current, further comprising: if the single cell voltage is greater than or equal to the preset fourth voltage, generating a stop charging instruction of the marine energy storage system; wherein the fourth voltage is greater than the third voltage; after the preset eighth time, acquiring the loop current of the marine energy storage system; if the loop current is less than or equal to the preset fifth current, powering off the marine energy storage system; if the loop current is greater than the fifth current, generating a charging fault information of the marine energy storage system.

[0151] Specifically, after the charging current of the marine energy storage system is reduced multiple times, when the single cell voltage is greater than or equal to the preset fourth voltage, such as 3.5V, it can be determined that the corresponding battery pack has completed charging, and the SOC thereof is calibrated to 100%, and a stop charging instruction of the marine energy storage system is generated, and then the loop current of the marine energy storage system is acquired after the preset eighth time, and it is judged whether the loop current is less than or equal to the preset fifth current, such as 5A, if the loop current is less than or equal to the fifth current, the charging switch, such as the disconnecting switch, in the first high-voltage box is disconnected first, and then the charging switch in the second high-voltage box is disconnected; if the loop current is greater than the fifth current, it can be determined that the power supply branch has a fault, and charging protection of the marine energy storage system is needed at this time, and a charging fault information of the energy storage system is generated. The eighth time can be 5s.

[0152] In addition, at any time during charging, if the ship management system sends a stop charging instruction to the battery management system, the battery management system can control the marine energy storage system to stop charging.

[0153] The charging method of the marine energy storage system provided by the application receives a charging instruction for charging the marine energy storage system, acquires the branch voltage of each power supply branch, determines the power-on strategy of the power supply branch, ensures the voltage consistency of each power supply branch in the charging stage, avoids the problem that the voltage consistency between the power supply branches of the marine energy storage system is poor after the charging is completed, and greatly improves the reliability and safety of the marine energy storage system.

[0154] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method of charging a marine energy storage system, characterized by, The ship energy storage system includes a plurality of power supply branches and a first high-voltage box, the plurality of power supply branches are connected in parallel, each power supply branch includes at least one battery pack and a second high-voltage box, the first high-voltage box is provided with a charging and discharging interface, and the first high-voltage box is electrically connected with the second high-voltage box; the charging method comprises: receiving a charging instruction for charging the ship energy storage system; obtaining the branch voltage of each power supply branch; determining the power-on strategy of the power supply branch according to the branch voltage, and closing the charging switch in the second high-voltage box according to the power-on strategy to power on the power supply branch; if all the power supply branches are powered on, the charging switch in the first high-voltage box is closed to charge the battery pack in each power supply branch through the first high-voltage box; determining the first power supply branch with the first branch voltage and the second power supply branch with the second branch voltage from the ship energy storage system according to the branch voltage; wherein the first branch voltage is less than or equal to the second branch voltage; closing the charging switch of the second high-voltage box in the first power supply branch to power on the first power supply branch; after the first power supply branch is powered on, obtaining the bus voltage of the ship energy storage system; generating a voltage difference between the second power supply branch and the bus of the ship energy storage system according to the second branch voltage and the bus voltage; closing the charging switch of the second high-voltage box in the second power supply branch according to the voltage difference to power on the second power supply branch. Before obtaining the branch voltage of each power supply branch, it further comprises:

2. The method of charging a marine energy storage system of claim 1, wherein, obtaining the charging information of the ship energy storage system; if the charging information is a preset first information, determining whether the communication connection between the charging and discharging interface and the charging pile is successful; if the communication connection between the charging and discharging interface and the charging pile is successful, performing fault detection on the ship energy storage system to obtain fault detection information of the ship energy storage system. After obtaining the charging information of the ship energy storage system, it further comprises:

3. The method of charging a marine energy storage system of claim 2, wherein, if the charging information is a preset second information, determining whether the charging instruction is valid; if the charging instruction is valid, determining whether the ship energy storage system is successfully connected with the ship management system; if the ship energy storage system is successfully connected with the ship management system, performing fault detection on the ship energy storage system to obtain the fault detection information. After obtaining the charging information of the ship energy storage system, it further comprises:

4. The method of charging a marine energy storage system of claim 2, wherein, if the charging information is a preset third information, determining whether the current at the charging and discharging interface flows from the charging and discharging interface to the battery pack; if the current flows from the charging and discharging interface to the battery pack, performing fault detection on the ship energy storage system to obtain the fault detection information. Before the fault detection on the ship energy storage system, it further comprises:

5. The method of charging a marine energy storage system according to any of claims 2-4, characterized in that, obtaining the current temperature of the battery pack; ​ If the current temperature is less than a preset first temperature, a heating instruction for heating the battery pack is generated; After a preset first time, the temperature of the battery pack is detected again to determine whether the marine energy storage system has a heating failure.

6. The method of charging a marine energy storage system of claim 1, wherein, The charging switch in the second high-voltage box includes a first charging switch and a second charging switch, and the second high-voltage box is further provided with an equalization switch, which is connected in parallel with the first charging switch; The closing of the charging switch of the second high-voltage box in the first power supply branch includes: The second charging switch and the equalization switch are sequentially closed; After a preset second time, the first charging switch is closed, and after a preset third time, the equalization switch is disconnected.

7. The method of charging a marine energy storage system of claim 1, wherein, The charging switch in the second high-voltage box includes a first charging switch and a second charging switch, and the second high-voltage box is further provided with an equalization switch, which is connected in parallel with the first charging switch; The closing of the charging switch of the second high-voltage box in the second power supply branch according to the voltage difference includes: If the voltage difference is less than a preset first voltage, the second charging switch and the first charging switch are sequentially closed; If the voltage difference is greater than or equal to the first voltage and less than or equal to a preset second voltage, the second charging switch and the equalization switch are sequentially closed; After a preset fourth time, the first charging switch is closed, and after a preset fifth time, the equalization switch is disconnected; If the voltage difference is greater than the second voltage, a charging protection instruction of the marine energy storage system is generated.

8. The method of charging a marine energy storage system of any of claims 1-4, wherein, The method further includes: If the marine energy storage system in the charging state is abnormal, abnormal information of the marine energy storage system is acquired; If the abnormal information does not trigger the power-off of the marine energy storage system, it is determined whether to trigger the reduction of the charging current of the marine energy storage system; If the reduction of the charging current of the marine energy storage system is triggered, the marine energy storage system is charged with a preset first current.

9. The method of charging a marine energy storage system of any of claims 1-4, wherein, The method further includes: When the marine energy storage system is in the charging state, the single-cell voltage of the battery cell in the battery pack is acquired; If the single-cell voltage is greater than or equal to a preset third voltage, the charging current of the marine energy storage system is adjusted to a preset second current; After a preset sixth time, the charging current of the marine energy storage system is adjusted to a preset third current; wherein the third current is less than or equal to the second current; After a preset seventh time, the charging current of the marine energy storage system is adjusted to a preset fourth current; wherein the fourth current is less than or equal to the third current.

10. The method of charging a marine energy storage system of claim 9, wherein, After the charging current of the marine energy storage system is adjusted to the preset fourth current, the method further includes: If the single-cell voltage is greater than or equal to a preset fourth voltage, a stop charging instruction of the marine energy storage system is generated; wherein the fourth voltage is greater than the third voltage; After a preset eighth time, the loop current of the marine energy storage system is acquired; If the loop current is less than or equal to a preset fifth current, the marine energy storage system is powered off; If the loop current is greater than the fifth current, charging fault information of the marine energy storage system is generated.

11. A marine energy storage system characterized by, The charging method of any one of claims 1-10 is applied to charge the marine energy storage system, which comprises a plurality of power supply branches and a first high-voltage box, each of the power supply branches comprises: at least one battery pack; a second high-voltage box, one end of the second high-voltage box being electrically connected to the battery pack; wherein the first high-voltage box is provided with a charging and discharging interface, one end of the charging and discharging interface being electrically connected to the other end of the second high-voltage box, and the other end of the charging and discharging interface being electrically connected to a marine power distribution system or / and a charging and discharging device.

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