A smart charging and swapping system for electric cargo ships and its design method

Abstract

An intelligent charging and swapping system and its design method for an electric cargo ship are disclosed. The system includes several battery modules, an intelligent charging device, and an intelligent swapping device. Each battery module, serving as the smallest operable and replaceable swapping unit, comprises M parallel-connected battery clusters and a battery management system, where M ≥ 1. Each battery cluster is formed by multiple cells connected in series. The number of battery modules in the ship's rated configuration is N. The actual number of battery modules loaded on the ship according to its actual voyage power requirements is n, where n ≤ N. The actual number of battery modules loaded is at least one greater than the theoretically calculated critical value, ensuring that if a single battery module fails, the remaining modules can support the ship's remaining voyage. This invention ensures sufficient power to support all ship propulsion, enables rapid charging and swapping, reduces the number of charging stations, significantly lowers costs, and maximizes economic benefits.

Description

Technical Field

[0001] This invention relates to the field of intelligent battery systems for electric ships, and in particular to an intelligent charging and swapping system for electric cargo ships and its design method. Background Technology

[0002] With the rapid development of new energy technologies, the energy density and safety reliability of power batteries are gradually improving. Simultaneously, with increasing environmental awareness and the improvement of relevant environmental regulations, the shift from fuel-powered to battery-powered transportation vehicles is becoming a trend. Furthermore, compared to conventional diesel-powered vessels, electric ships have significant advantages in terms of both operating costs and ship intelligence.

[0003] It's important to note that small cruise ships don't require high battery capacity, so the power and capacity requirements of the batteries used are relatively low, making electrification relatively easy. Electric vessels are already widely used in various scenic spots. Large ships, however, have much higher requirements for power and range, making pure electric electrification currently difficult. This invention is primarily aimed at electric cargo ships used for fixed-route operations.

[0004] Unlike ships used for other purposes, cargo ships have relatively defined and fixed routes and voyages, with specific outbound and return loads. Therefore, the battery capacity and power requirements for the outbound and return voyages are clearly defined. Examples include cargo ships used to transport coal fuel, traveling between raw material cargo terminals and thermal power plants.

[0005] Because ships have limited berthing time after docking, AC charging (slow charging) is insufficient to meet the operational time requirements of electric cargo ships. While DC fast charging devices are widely used, charging times for large-capacity batteries remain excessively long. Specifically, for a typical 4000kWh cargo ship, using two 480kW DC fast chargers simultaneously would still take over 4 hours to charge. For operational cargo ships, this represents a significant waste of time waiting to charge, drastically reducing operational efficiency. Furthermore, DC fast charging, especially with its high current, places extremely high demands on cables, and the ship's continued movement with the current while in port poses a considerable challenge to the lifespan of the charging interfaces. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and provide an intelligent charging and swapping system for electric cargo ships with fast charging speed and low cost, as well as its design method.

[0007] The technical solution of this invention is:

[0008] An intelligent charging and swapping system for an electric cargo ship according to the present invention includes:

[0009] The system comprises several battery modules, which serve as the smallest operable and replaceable battery swapping unit. Each battery module includes M parallel-connected battery clusters and a battery management system, where M ≥ 1. Each battery cluster is formed by multiple battery cells connected in series. The number of battery modules in the ship's rated configuration is N. The actual number of battery modules loaded on the ship according to the actual power demand during navigation is n, where n ≤ N. The actual number of battery modules loaded must be at least 1 greater than the critical point of the theoretically calculated configuration, so that if a single battery module fails, the remaining battery modules can support the ship to complete the remaining navigation. The battery management system is used for charging, discharging, starting, stopping, and balancing control of the battery modules, monitoring the voltage, current, and temperature of the battery cells, and communicating with the back-end management platform or intelligent charging device.

[0010] The intelligent charging device, located at the charging station, is used to provide electrical energy for charging the battery module and communicates with the battery management system to obtain parameter information of the battery module.

[0011] Intelligent battery swapping devices, located at battery swapping stations, are used to transport used battery modules to charging stations and to load fully charged battery modules onto ships.

[0012] Furthermore, the plurality of battery modules are connected in parallel to the busbars of the ship.

[0013] Furthermore, the battery module also includes a touchscreen and indicator lights connected to the battery management system; the MCU of the battery management system includes an arithmetic logic module, an ADC module, a CAN module, and a UART module; the battery module is connected to the arithmetic logic module via a charge / discharge control module and an equalization module to control the charge / discharge start / stop and equalization of the battery module; the arithmetic logic module is also used to calculate the SOC and SOH of the battery module; the battery module is also connected to a cell temperature sensor for detecting cell temperature and a voltage / current detection sensor for detecting cell voltage and current; the cell temperature sensor and the voltage / current detection sensor are both connected to the ADC module of the BMS for monitoring the voltage, current, and temperature of the cells; the output of the arithmetic logic module is connected to indicator lights; the CAN module is used to communicate with the upper-level management platform or smart charging device; the UART module is connected to the touchscreen to monitor the parameter information of the battery module through the touchscreen.

[0014] Furthermore, the intelligent charging device includes:

[0015] A high-power DC power supply module is used to provide electrical energy for charging the battery module;

[0016] A communication module for communicating with the battery management system;

[0017] The human-computer interaction module includes a touch screen and a back-end management platform. The touch screen is used to set and check the status of a single smart charging device. The back-end management platform is a platform that aggregates all smart charging devices, collects information and centrally controls the smart charging devices connected to the system, and generates operation information records to assist in the formulation of subsequent charging and control strategies.

[0018] The main control module is used to integrate external commands and the current operating status of the system to control the entire system. When the system malfunctions, it promptly initiates corresponding alarm and protection actions.

[0019] The charging interface module is used to connect several battery modules.

[0020] Furthermore, the intelligent battery swapping device includes a lifting device and a transport device. The transport device is located between the battery swapping station and the charging station and transports fully charged or ready-to-charge battery modules through a predetermined transmission path.

[0021] The present invention discloses a design method for an intelligent charging and swapping system for an electric cargo ship, including the specification design of the battery module, and the steps are as follows:

[0022] (1) The actual use scenario of cargo routes is designed to be "carrying goods downstream and returning upstream";

[0023] (2) The actual number of battery modules installed in the design should be at least 1 greater than the critical point of the theoretically calculated number of modules;

[0024] (3) Multiple cells are connected in series to form a battery cluster that reaches the working voltage, and its capacity C rack Depending on the cell model, once the DC bus voltage design value is determined, the number of cells in series is a fixed value; the smallest battery swapping unit is formed by M battery clusters connected in parallel, which is a single and indivisible battery module, where M≥1;

[0025] (4) The capacity of a single battery module is denoted as w. P Then w P =M*C rack The rated number of battery modules in the entire vessel is N, meaning the maximum capacity of the entire vessel is N*w. P ;

[0026] (5) The total energy requirement of a fully loaded cargo ship from the loading point to the unloading point is W. f The total energy requirement for an empty ship to return from the unloading point to the loading point is W0; in actual operation, the ship's route operation process W0 and W f The following relationship must be satisfied:

[0027]

[0028] In the formula, E(X) represents the expected value;

[0029] (6) If the actual power demand of the ship during navigation does not reach the design capacity, the number of battery modules will be reduced. The actual number of battery modules loaded will be denoted as n, and the number of battery modules in the ship under full load will be n. f =N; Considering the boundary condition of maximum under full load throughout the entire process, i.e.: n f ≥W f / w P +1; In actual practice, the preferred configuration of the ship's battery modules is n. f =W f / w P +1; The number of battery modules during the empty return process is n0 = W0 / w P +1.

[0030] Furthermore, it also includes a charging design method for intelligent charging devices, with the following steps: For the battery module of the smallest battery swapping unit, a fast charging scheme is adopted, and its charging time is approximately estimated to be M hours, where M is the number of battery clusters in the battery module; it is assumed that the number of battery modules to be charged is N; the unloading time of the ship during the docking process is t hours; considering the combined operating time and daytime working time, the maximum number of ship stops at a single berth on the route in a day is calculated as 12 / t ship calls; there are multiple berths for the same type of ship operating in the port, with the number of berths being X; when the number of battery modules in the battery swapping station is less than N*X, the battery modules in the charging station are immediately fast charged to replenish the number of battery modules in the battery swapping station.

[0031] Furthermore, another charging design method for intelligent charging devices is also included, with the following steps: prioritizing operational economy, the battery modules are charged uniformly when electricity prices are low; the charging start time and charging current are set and the charging sequence is configured on the background management platform, and (12 / t)*N*X battery modules are fully charged within 8 hours at night; for the construction of intelligent charging devices, the number of them meets (8 / M)*(12 / t)*N*X, that is, N*X*96 / (M*t) DC fast charging interfaces.

[0032] Furthermore, the design method for intelligent battery swapping devices is also included, with the following steps: The charging station and battery swapping station are spatially separated, and a transportation device is established between them; after each battery module is fully charged at the charging station in the morning, the battery cabinet is transported from the charging station to the battery swapping station using a bidirectional conveyor belt or other conveyor machine; after the ship arrives at port, the fully charged battery modules at the battery swapping station are placed at the berth, and then the battery modules waiting to be charged stored at the berth are placed at the battery swapping station. This process is repeated until all ships have completed battery swapping within a day; once all swaps are complete, the battery cabinets from the battery swapping station are transported to the charging station for charging using the transportation device.

[0033] Furthermore, M battery clusters are connected in parallel to form a battery module, where M≤8.

[0034] The beneficial effects of this invention are:

[0035] This invention utilizes the battery module as the smallest operable and replaceable battery swapping unit throughout the entire system's operation, charging, and navigation processes. The battery module configuration is designed to ensure sufficient power to support all ship power while enabling rapid charging and swapping. This battery swapping solution significantly reduces the time ships spend in port, at least doubling the number of operational trips compared to charging at port, resulting in substantial economic gains. Furthermore, it integrates with intelligent charging devices, reducing the number of charging stations, greatly lowering costs, and maximizing economic benefits. The intelligent battery swapping device's charging scheme is designed with operational economics in mind, allowing for unified charging of battery modules during periods of low electricity prices, achieving fast charging while saving on electricity costs. Combined with the intelligent battery swapping device, the designed swapping scheme ensures a clear transmission path for the battery modules, with charging and swapping occurring sequentially, enabling better unattended automatic operation.

[0036] Furthermore, when charging at land-based charging stations after battery swapping, the charging cable remains stationary during the charging process. This avoids the problems of cable swaying, friction, and stress on the connectors that might occur with the boat's movement with the water flow, allowing the use of ordinary cables and connectors. Otherwise, charging on a boat requires cables with high strength, impact resistance, abrasion resistance, and corrosion resistance. This necessitates the use of cables with "fixed ends and a retractable middle section." Otherwise, excessive stress could easily damage the cable connectors, requiring the addition of retractable support hinges and connector fixing devices. Attached Figure Description

[0037] Figure 1 This is a structural diagram of the battery module according to an embodiment of the present invention;

[0038] Figure 2 This is a functional block diagram of the battery module according to an embodiment of the present invention;

[0039] Figure 3 This is a functional diagram illustrating the parallel networking of battery modules on a ship according to an embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the composition of the intelligent charging device according to an embodiment of the present invention;

[0041] Figure 5 This is a diagram illustrating the design of the intelligent battery swapping device according to an embodiment of the present invention, which separates the charging station and the battery swapping station spatially.

[0042] Figure 6 for Figure 5 An enlarged schematic diagram of the left half of the embodiment shown;

[0043] Figure 7 for Figure 5 An enlarged schematic diagram of the right half of the embodiment shown. Detailed Implementation

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] An intelligent charging and swapping system for an electric cargo ship includes several battery modules, an intelligent charging device, and an intelligent swapping device; the several battery modules are connected in parallel to the ship's busbars.

[0046] like Figures 1-3 As shown: In this embodiment, the battery module is the smallest operable and replaceable battery swapping unit during the entire system's use, charging, and navigation processes. Specifically, it includes M parallel-connected battery clusters, a battery management system (BMS), indicator lights, and a touchscreen. The battery module is protected by structural components (including connectors) with a certain level of protection, and the overall structure has both automatic and manual unlocking functions to ensure the reliability of the battery module on board and at charging stations.

[0047] The Battery Management System (BMS) is responsible for monitoring, control, and communication functions. Specifically, the BMS's MCU includes an arithmetic logic unit (ALU), an ADC module, a CAN module, and a UART module. The battery module is connected to the ALU via a charge / discharge control module and also via an equalization module for charge / discharge start / stop and equalization control. The ALU is also used to calculate the battery module's State of Charge (SOC) and State of Health (SOH). The battery module is also connected to a cell temperature sensor for detecting cell temperature and a voltage / current sensor for detecting cell voltage and current. Both the cell temperature sensor and the voltage / current sensor are connected to the BMS's ADC module for monitoring cell voltage, current, and temperature. Indicator lights are connected to the output of the ALU. The CAN module communicates with the host computer (including the upper-level BMS and intelligent charging device). The UART module connects to a touchscreen, which serves as the battery module's human-machine interface. Operators can visually view the battery module's charge / discharge status, cell voltage, temperature, SOC, and SOH information through the touchscreen; simultaneously, operators can modify and configure parameters via the touchscreen.

[0048] like Figure 4 As shown: In this embodiment, the intelligent charging device is an intelligent charging pile located in the charging station, and mainly includes a high-power DC power supply module, a communication module, a human-machine interaction module, a main control module, and a charging interface module.

[0049] The system comprises several key components: a high-power DC power supply module to provide charging power, with adjustable voltage and current within the rated power range; a communication module for communication between the smart charging device and the battery module's BMS (Battery Management System) to exchange information such as charging current, SOC (State of Charge), cell temperature, and interface temperature, ensuring safe and stable operation throughout the charging process; a human-machine interface module consisting of a touchscreen and a backend management platform; a touchscreen for easy setup and status checks of individual smart charging devices; and a centralized control platform for all connected smart charging devices, generating operational records to support subsequent charging and control strategy development; a main control module, the core control unit for the smart charging device, integrating external commands and the system's current operating status to control the entire system; and an alarm and protection mechanism to promptly trigger alarms and protection actions in case of system malfunctions, ensuring system safety and reliability; and a charging interface module connecting multiple battery modules to the smart charging device, including a high-voltage interface for charging, a low-voltage interface for powering the control circuits, a communication interface with the BMS, and charging connection signals.

[0050] In this embodiment, the intelligent battery swapping device is located at the battery swapping station and includes a lifting device and a transportation device. It is used to transport used battery modules to the charging station and to load fully charged battery modules onto the ship. The deployment of the transportation device is determined by the actual conditions of the port, primarily depending on the distance from the ship's berth to the battery swapping station and the charging station.

[0051] In this embodiment, one deployment method for the intelligent battery swapping device is as follows: the charging station and the battery swapping station are spatially separated. The battery swapping station only stores battery modules that are fully charged, while battery modules awaiting charging are stored at the charging station or are currently being charged there. In this case, a transportation device must also be established between the battery swapping station and the charging station to transfer fully charged battery modules from the charging station to the battery swapping station. In this embodiment, automated / semi-automated transportation tools such as tracks, conveyor belts, AGVs, and electric forklifts can be used to achieve automatic operation. Through this method, the transmission path of the battery modules is clear, and charging and battery swapping are performed sequentially, which can better achieve unattended automatic operation.

[0052] Another deployment method for intelligent battery swapping devices involves no spatial distinction between charging stations and swapping stations. Users manually determine whether the battery module is fully charged and ready for use on the ship using touchscreens and indicator lights on the battery module. However, this method requires significant manual intervention, and the battery module transfer path varies each time, making automated operation difficult to achieve later.

[0053] This invention discloses a design method for an intelligent charging and swapping system for an electric cargo ship, mainly including the design of battery modules, the charging design of intelligent charging devices, and the battery swapping design method of intelligent swapping devices. Details are as follows:

[0054] In this embodiment, the battery module, as the smallest operable and replaceable battery swapping unit, must have its capacity designed to maximize economic benefits while meeting the requirements of the flight route. Therefore, the specification design method for the battery module includes:

[0055] Condition 1: The actual use scenario of the cargo route of this invention is mainly designed for "carrying goods downstream and returning upstream", and it is not applicable to the very rare scenario of "carrying goods upstream and returning downstream".

[0056] Condition 2: In order to ensure that the failure of a single battery module does not affect navigation, the battery module design of electric ships must have a certain margin of safety. Therefore, the actual number of battery modules should be at least 1 greater than the critical point of the theoretical calculation. In addition, since the ship's self-weight design greatly affects the ship's economic efficiency and safety, in actual design and use, the battery module configuration of the ship is taken as the critical point of the theoretical calculation plus 1.

[0057] Condition 3: Multiple cells are connected in series to form a battery cluster that reaches the operating voltage, and its capacity C rack Depending on the cell model, the number of cells in series is a fixed value once the DC bus voltage design value is determined; however, this does not mean that the battery cluster is the smallest battery swapping unit. In actual operation, the smallest battery swapping unit is composed of M (M≥1) battery clusters connected in parallel, which is a single and indivisible battery module in structure.

[0058] Condition 4: Record the capacity of a single battery module as w. P Then w P =M*C rack The rated number of battery modules in the entire vessel is N, where N≥1, meaning the maximum capacity of the entire vessel is N*w. p Where N is a constant for a given ship type.

[0059] Condition 5: The total energy requirement for a fully loaded cargo ship from the loading point to the unloading point is W. f The total energy requirement for an unloaded vehicle to return from the unloading point to the loading point is W0; the relationship between W0 and W in the calculation process... f We will temporarily disregard relatively minor influencing factors such as weather and shipping regulations. In actual operation, the ship's route operation process W0 and W... f The following relationship must be satisfied:

[0060]

[0061] In the formula, E(X) represents the expected value.

[0062] Condition 6: If the actual power demand during the ship's voyage does not reach the design capacity, the number of battery modules can be reduced to decrease weight and operational costs. Let n be the actual number of battery modules loaded; the number of battery modules on the ship when fully loaded with cargo is always n. f = N (N is the number of battery modules in the aforementioned rated configuration, n is the number of battery modules loaded according to actual conditions, and n≤N); Furthermore, even if a single battery module fails, the remaining battery modules can still support the entire vessel to complete the remaining voyage. Considering the full-load full-range state, this is the maximum boundary condition, i.e.: n f ≥W f / w P +1 (rounding up during the calculation), refer to condition 2 above; although a sufficiently large amount of electricity is enough to support all the power of the ship, considering economics, in practice, the battery module configuration of the ship is taken as n. f =W f / w P +1 (rounding up during the calculation), at this point W f The calculation should consider full load and low water flow velocity (ideal calculation model can be considered as 0), i.e., W f max. The number of battery modules during the no-load return process, n0 = W0 / w P +1.

[0063] Condition 7: In addition to the total capacity meeting the navigation requirements, the instantaneous output power demand of the battery module should also be considered. This is because the operation of the ship's motors includes the start-up and maintenance processes, and the required power must be less than the power that the battery module can output at that time. Otherwise, there will be a situation where the battery module has sufficient capacity, but the battery module's power output capability is insufficient.

[0064] Considering the above factors, and taking into account the electric cargo ship's own load capacity and return on investment (including the construction of port battery swapping facilities and the service life of product loading and unloading), a suitable range is selected as the minimum battery swapping unit in the ship's power system. Finally, by selecting the DC bus voltage and calculating the full-load power, the calculation is converted into the calculation of the number of battery clusters connected in parallel, M. Preferably, M can be any number from 1 to 8. Based on practical experience, for a 3000-ton cargo ship, M=4 yields the greatest overall benefit.

[0065] In this embodiment, to improve the flexibility and economic efficiency of the entire ship operation process, the intelligent charging device provides users with a variety of charging strategies. The specific charging scheme design method is as follows:

[0066] Under normal circumstances, for common battery cells and DC fast charging systems on the market, a single battery cluster can be fully charged in about 1 hour using fast charging. For the smallest battery swapping unit—the battery module—using a fast charging solution, the charging time can be approximately estimated as M (i.e., the number of battery clusters in the aforementioned battery module) hours. The number of battery modules that are swapped out is N (considering extreme cases, the spare battery also needs to be swapped out for charging). During the process of a ship docking, its unloading time is approximately t hours. Considering the combined operating time and daytime working hours, the maximum number of times a ship stops at a single berth on the route in a day can be calculated as 12 / t ship calls. There are multiple berths for the same type of ship operating in the port, with the number of berths being X.

[0067] The first strategy is to ensure the number of replaceable battery modules at the battery swapping station is available in an instant fast charging mode. When the number of battery modules in the battery swapping station is less than N*X (N represents the number of battery modules in the rated configuration of a cargo ship), the battery modules in the charging station are immediately fast charged to replenish the number of battery modules in the battery swapping station.

[0068] The second strategy prioritizes operational economics, implementing unified (scheduled) charging of battery modules during periods of low electricity prices. Specifically, this can be configured on the backend management platform software by setting the charging start time, charging current, and charging sequence. Preferably, the charging start time is set to 11 PM (the lowest point in local electricity prices), the charging current is set to the maximum, and the charging sequence is set according to the charging gun ports. The number of smart charging stations is designed for economic efficiency, considering that (12 / t)*N*X battery modules can be fully charged within 8 hours at night. Therefore, the number of smart charging stations should meet the requirement of (8 / M)*(12 / t)*N*X, or N*X*96 / (M*t) DC fast charging interfaces.

[0069] Compared to solutions that do not utilize smart charging devices, the construction of existing charging piles requires a quantity that meets the requirement of (12 / t)*N*X. The larger M is in this invention, the fewer charging piles are needed, resulting in lower costs.

[0070] like Figures 5-7 As shown: In this embodiment, the design method of the intelligent battery swapping device includes:

[0071] The charging station and battery swapping station are spatially separated, and a transportation system is established between them. In the morning, after each battery module is fully charged at the charging station, the battery cabinet is transported from the charging station to the battery swapping station using a bidirectional conveyor belt or other conveyor machinery. Each battery cabinet can hold a total of 48 battery modules. Upon arrival of the ship, the fully charged battery modules from the battery swapping station are placed at the berth. Then, the battery modules awaiting charging at the berth are moved to the battery swapping station, and forklifts are used for replacement. This process continues until all ships have had their batteries swapped within a day, meaning all 48 battery modules awaiting charging are in the battery cabinet at the battery swapping station. Once all swaps are complete, the battery cabinet from the battery swapping station is transported to the charging station for charging, and this cycle repeats. This method provides a clear transmission path for the battery modules, and the charging and swapping processes are sequential, enabling relatively unattended automated operation.

[0072] In summary, this invention utilizes the battery module as the smallest operable and replaceable battery swapping unit throughout the entire system's operation, charging, and navigation processes. The battery module configuration is designed to ensure sufficient power to support all ship propulsion, enable rapid charging and swapping, and integrate with intelligent charging devices to reduce the number of charging stations, significantly lowering costs and maximizing economic benefits. Furthermore, the intelligent battery swapping device's charging scheme is designed with operational economics in mind, allowing for unified charging of battery modules during off-peak electricity prices, achieving fast charging while saving on electricity costs. Combined with the intelligent battery swapping device, the designed swapping scheme ensures a clear transmission path for the battery modules, with charging and swapping occurring sequentially, enabling better unattended automatic operation.

Claims

1. A design method for an intelligent charging and swapping system for an electric cargo ship, characterized in that, The steps, including the specification design of the battery module, are as follows: (1) The actual use scenario of cargo routes is designed to be "carrying goods downstream and returning upstream"; (2) The actual number of battery modules installed in the design should be at least 1 greater than the critical point of the theoretically calculated number of modules; (3) Multiple cells are connected in series to form a battery cluster that reaches the working voltage, and its capacity C rack Depending on the cell model, once the DC bus voltage design value is determined, the number of cells in series is a fixed value; the smallest battery swapping unit is formed by M battery clusters connected in parallel, which is a single and indivisible battery module, where M≥1; (4) The capacity of a single battery module is denoted as w. P Then w P =M*C rack The rated number of battery modules in the entire vessel is N, meaning the maximum capacity of the entire vessel is N*w. P ; (5) The total energy requirement of a fully loaded cargo ship from the loading point to the unloading point is W. f The total energy requirement for an empty ship to return from the unloading point to the loading point is W0; in actual operation, the ship's route operation process W0 and W f The following relationship must be satisfied: ； In the formula, E(X) represents the expected value; (6) If the actual power demand of the ship during navigation does not reach the design capacity, the number of battery modules will be reduced. The actual number of battery modules loaded will be denoted as n, and the number of battery modules in the ship under full load will be n. f =N; Considering the boundary condition of maximum under full load throughout the entire process, i.e.: n f ≥W f / w P +1; In actual practice, the battery module configuration of the ship is taken as n. f =W f / w P +1; The number of battery modules during the empty return process is n0 = W0 / w P +1; The steps for designing a charging system using a smart charging device are as follows: (7) For the battery module of the smallest battery swapping unit, a fast charging scheme is adopted, and its charging time is estimated to be M hours, where M is the number of battery clusters in the battery module; it is assumed that the number of battery modules to be charged is N; the unloading time of the ship during the docking process is t hours; taking into account the combined operating time and daytime working time, the maximum number of times a single berth on the route stops in a day is calculated as 12 / t ship times; there are multiple berths for the same type of ship operating in the port, and the number of berths is X; when the number of battery modules in the battery swapping station is less than N*X, the battery modules in the charging station are immediately fast charged to supplement the number of battery modules in the battery swapping station. (8) Prioritize the economic efficiency of operation, and charge the battery modules uniformly when the electricity price is low; set the charging start time and charging current and configure the charging sequence in the background management platform, and fully charge (12 / t)*N*X battery modules within 8 hours at night; for the construction of intelligent charging devices, the number of them should meet (8 / M)*(12 / t)*N*X, that is, N*X*96 / (M*t) DC fast charging interfaces.

2. The design method of the intelligent charging and swapping system for electric cargo ships according to claim 1, characterized in that, It also includes the design method of intelligent battery swapping device, the steps of which are as follows: the charging station and the battery swapping station are spatially separated, and a transportation device is established between the battery swapping station and the charging station; after each battery module is charged at the charging station in the morning, the battery cabinet is transported from the charging station to the battery swapping station, and the transportation method is a two-way conveyor belt or other conveyor machine. After the ships arrive at the port, the fully charged battery modules from the battery swapping station are placed at the berth, and then the battery modules waiting to be charged stored at the berth are placed at the battery swapping station. This process is repeated until all ships have had their batteries swapped within a day. Once all swaps are completed, the battery cabinets from the battery swapping station are transported to the charging station for charging using a transport device.

3. The design method of the intelligent charging and swapping system for electric cargo ships according to claim 1, characterized in that, M battery clusters are connected in parallel to form a battery module, where M≤8.

4. The intelligent charging and swapping system for an electric cargo ship, as described in the design method of the intelligent charging and swapping system for an electric cargo ship according to claim 1, is characterized in that... include: The system comprises several battery modules, which serve as the smallest operable and replaceable battery swapping unit. Each battery module includes M parallel-connected battery clusters and a battery management system, where M ≥ 1. Each battery cluster is formed by multiple battery cells connected in series. The number of battery modules in the ship's rated configuration is N. The actual number of battery modules loaded on the ship according to the actual power demand during navigation is n, where n ≤ N. The actual number of battery modules loaded must be at least 1 greater than the critical point of the theoretically calculated configuration, so that if a single battery module fails, the remaining battery modules can support the ship to complete the remaining navigation. The battery management system is used for charging, discharging, starting, stopping, and balancing control of the battery modules, monitoring the voltage, current, and temperature of the battery cells, and communicating with the back-end management platform or intelligent charging device. The intelligent charging device, located at the charging station, is used to provide electrical energy for charging the battery module and communicates with the battery management system to obtain parameter information of the battery module. Intelligent battery swapping devices, located at battery swapping stations, are used to transport used battery modules to charging stations and to load fully charged battery modules onto ships.

5. The intelligent charging and swapping system for electric cargo ships according to claim 4, characterized in that, The battery modules are connected in parallel to the ship's busbars.

6. The intelligent charging and swapping system for electric cargo ships according to claim 4, characterized in that, The battery module also includes a touch screen and indicator lights connected to the battery management system; the MCU of the battery management system includes an arithmetic logic module, an ADC module, a CAN module, and a UART module. The battery module is connected to the computational logic module via a charge / discharge control module and an equalization module to control the start / stop of charging / discharging and equalization of the battery module. The computational logic module is also used to calculate the SOC and SOH of the battery module. The battery module is also connected to a cell temperature sensor for detecting cell temperature and a voltage / current detection sensor for detecting cell voltage and current. Both the cell temperature sensor and the voltage / current detection sensor are connected to the BMS's ADC module for monitoring the voltage, current, and temperature of the cells. The output of the computational logic module is connected to an indicator light. The CAN module is used to communicate with the upper-level management platform or smart charging device. The UART module is connected to a touch screen to monitor the parameter information of the battery module.

7. The intelligent charging and swapping system for electric cargo ships according to claim 4, characterized in that, The intelligent charging device includes: A high-power DC power supply module is used to provide electrical energy for charging the battery module; A communication module for communicating with the battery management system; The human-computer interaction module includes a touch screen and a back-end management platform. The touch screen is used to set and check the status of a single smart charging device. The back-end management platform is a platform that aggregates all smart charging devices, collects information and centrally controls the smart charging devices connected to the system, and generates operation information records to assist in the formulation of subsequent charging and control strategies. The main control module is used to integrate external commands and the current operating status of the system to control the entire system. When the system malfunctions, it promptly initiates corresponding alarm and protection actions. The charging interface module is used to connect several battery modules.

8. The intelligent charging and swapping system for electric cargo ships according to claim 4, characterized in that, The intelligent battery swapping device includes a lifting device and a transport device. The transport device is located between the battery swapping station and the charging station and transports fully charged or ready-to-charge battery modules through a predetermined transmission path.

Images