Multi-task working condition-oriented ship power system and modeling operation method thereof

Abstract

The invention provides a multi-task working condition oriented ship power system and a modeling operation method thereof. The multi-task working condition oriented ship power system modeling operation method is realized based on a multi-task working condition oriented ship power system, and comprises the following steps: according to an instruction of a superior control system and the task working condition of a ship, a power management module controls the power system to enter an operation mode corresponding to the task working condition; the task working conditions comprise berthing and standby sailing of a ship, high-speed sailing propelled by a diesel main engine, air supply of an air bottle, low-speed sailing propelled by electric power, a certain high-power task and on-ship maintenance operation of personnel, and the corresponding power system operation modes comprise a shore power mode, a charging mode, an air supply mode, a battery mode, a heavy load mode and a shutdown mode. The electric power system and the superior control system only need to interact mode information, the information interaction amount of the superior control system and the electric power system is greatly reduced, and the use difficulty of ship operators and users is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power system operation, and in particular to a ship power system for multi-task working conditions and a mode operation method thereof. BACKGROUND

[0002] Power system operation refers to providing continuous and sufficient electric energy that meets the requirements of electric power quality to power users as safely and stably as possible on the basis of fully and reasonably utilizing and deploying the energy and operation equipment capacity of the whole ship. In recent years, with the development of new power systems, the in-depth application of source-grid-load-storage collaborative optimization technology, flexible AC / DC hybrid transmission and distribution technology, and intelligent dispatching technology in various fields has made the safe, stable and efficient operation of power systems a research hotspot.

[0003] In the field of ships, the safe, stable and efficient operation of the power system is related to the vitality of the ship and the reliability of the execution of various tasks, and the task working conditions of the current ship design are gradually diversified and complicated. However, the operators and users of the ship are often not familiar with the specific control logic inside the power system, and how to make the power system accurately meet different power demands during the execution of various complex tasks of the ship to ensure the reliable execution of various tasks has become a difficulty in the operation of the ship power system. At present, there is no good solution to this problem from the engineering application perspective, which brings risks and challenges to the operators and users of the ship. SUMMARY

[0004] The present application provides a ship power system for multi-task working conditions and a mode operation method thereof to solve the problems in the background art.

[0005] In a first aspect, the present application provides a ship power system for multi-task working conditions, comprising a diesel generator set, a lithium battery energy storage device, a direct current power distribution system, and an alternating current power distribution system. The diesel generator set comprises a No. 1 generator set and a No. 2 generator set, and the lithium battery energy storage device comprises a No. 1 lithium battery set and a No. 2 lithium battery set. The direct current power distribution system comprises a No. 1 direct current power distribution board and a No. 2 direct current power distribution board; the No. 1 direct current power distribution board comprises a 1kV direct current busbar, a No. 1 DC / DC power conversion module, a No. 1 DC / AC power conversion module, a No. 1 AC / DC power conversion module, and a power management module; and the No. 2 direct current power distribution board comprises a 1kV direct current busbar, a No. 2 DC / DC power conversion module, a No. 2 DC / AC power conversion module, a No. 2 AC / DC power conversion module, and a power management module. The AC power distribution system comprises a No. 1 isolation transformer, a No. 2 isolation transformer, a No. 1 AC power distribution board, and a No. 2 AC power distribution board; the No. 1 AC power distribution board comprises a 400V AC busbar, and the No. 2 AC power distribution board comprises a 400V AC busbar and a shore power box, which is connected with the 400V AC busbar of the No. 2 AC power distribution board through a shore power switch; The No. 1 generator set is connected to the 1kV DC busbar of the No. 1 DC power distribution board through the No. 1 AC / DC power conversion module, thereby forming a No. 1 generator set branch; and the No. 2 generator set is connected to the 1kV DC busbar of the No. 2 DC power distribution board through the No. 2 AC / DC power conversion module, thereby forming a No. 2 generator set branch; The No. 1 lithium battery set is connected to the 1kV DC busbar of the No. 1 DC power distribution board through the No. 1 DC / DC power conversion module, thereby forming a No. 1 battery set branch; and the No. 2 lithium battery set is connected to the 1kV DC busbar of the No. 2 DC power distribution board through the No. 2 DC / DC power conversion module, thereby forming a No. 2 battery set branch; The 1kV DC busbar of the No. 1 DC power distribution board is connected to the 400V AC busbar of the No. 1 AC power distribution board through the No. 1 DC / AC power conversion module and the No. 1 isolation transformer, thereby forming a No. 1 DC / AC branch; and the 1kV DC busbar of the No. 2 DC power distribution board is connected to the 400V AC busbar of the No. 2 AC power distribution board through the No. 2 DC / AC power conversion module and the No. 2 isolation transformer, thereby forming a No. 2 DC / AC branch; The power management module is used for controlling the power system to enter a running mode corresponding to a task working condition of the ship according to a task working condition of the ship and a command of a superior control system, and simultaneously feeding back power system running state monitoring quantities and alarm quantities to the superior control system in real time; A tie switch is arranged between the No. 1 AC power distribution board and the No. 2 AC power distribution board, and is used for connecting the 400V AC busbar of the No. 1 AC power distribution board and the 400V AC busbar of the No. 2 AC power distribution board; the 400V AC busbar of the No. 2 AC power distribution board is divided into two parts by a busbar jumper switch, so as to realize segmented running or parallel running of the No. 1 AC power distribution board and the No. 2 AC power distribution board.

[0006] Further, the DC power distribution system further comprises a No. 1 electric power propulsion device and a No. 2 electric power propulsion device; the No. 1 electric power propulsion device comprises a No. 1 propulsion motor and a No. 1 propulsion frequency converter, and the No. 2 electric power propulsion device comprises a No. 2 propulsion motor and a No. 2 propulsion frequency converter; The 1kV DC bus bar of the first DC distribution board is connected to the first propulsion frequency converter through the 1# propulsion 1# DC bus bar fuse, providing main power supply for the first electric propulsion device; and the 1kV DC bus bar of the first DC distribution board is connected to the second propulsion frequency converter through the 2# propulsion 1# DC bus bar fuse, providing standby power supply for the second electric propulsion device. The 1kV DC bus bar of the second DC distribution board is connected to the second propulsion frequency converter through the 2# propulsion 2# DC bus bar fuse, providing main power supply for the second electric propulsion device; and the 1kV DC bus bar of the second DC distribution board is connected to the first propulsion frequency converter through the 1# propulsion 2# DC bus bar fuse, providing standby power supply for the first electric propulsion device.

[0007] Further, the AC power distribution system further comprises a first daily transformer and a second daily transformer; the first AC distribution board further comprises a 230V AC bus bar, and the second AC distribution board further comprises a 230V AC bus bar; The 400V AC bus bar of the first AC distribution board is connected to the 230V AC bus bar of the first AC distribution board through the first daily transformer, and the 400V AC bus bar of the second AC distribution board is connected to the 230V AC bus bar of the second AC distribution board through the second daily transformer.

[0008] In a second aspect, the application provides a ship power system mode operation method for multi-task working conditions, which is based on the ship power system for multi-task working conditions as described above; The ship power system mode operation method for multi-task working conditions comprises the following steps: According to the instructions of the upper control system, the power management module controls the power system to enter the operation mode corresponding to the task working condition according to the task working condition of the ship; The task working conditions include berthing, diesel main engine propulsion high-speed sailing, air bottle air charging, electric propulsion low-speed sailing, certain high-power task, and personnel boarding for maintenance operation, and the corresponding power system operation modes include shore power mode, charging mode, air charging mode, battery mode, heavy load mode, and shutdown mode.

[0009] Further, the step of controlling the power system to enter the shore power mode by the power management module comprises: The shore power switch connected to the 400V AC bus bar of the second AC distribution board is turned on, and the bus bar cross connection switch is turned on to make the first AC distribution board and the second AC distribution board operate in parallel; The first daily reverse branch, the second daily reverse branch, the first battery branch, and the second battery branch are all turned on, so that the first lithium battery pack and the second lithium battery pack are both in the charging state, and the first generator set and the second generator set are both in the shutdown state.

[0010] Further, the step of controlling the power system to enter the charging mode by the power management module comprises: controlling the busbar cross connection switch to open to make the No. 1 AC distribution board and the No. 2 AC distribution board run independently; controlling the No. 1 daily reverse branch, the No. 2 daily reverse branch, the No. 1 battery branch, the No. 2 battery branch, the No. 1 unit branch and the No. 2 unit branch to be all turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in the charging state, and the No. 1 generator set and the No. 2 generator set are both in the running state.

[0011] Further, the step of controlling the power system to enter the gas supplement mode by the power management module comprises: controlling the busbar cross connection switch to open to make the No. 1 AC distribution board and the No. 2 AC distribution board run independently; controlling the No. 1 unit branch, the No. 2 unit branch, the No. 1 daily reverse branch, the No. 2 daily reverse branch, the No. 1 battery branch and the No. 2 battery branch to be all turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in the floating charging state, and the No. 1 generator set and the No. 2 generator set are both in the running state.

[0012] Further, the step of controlling the power system to enter the battery mode by the power management module comprises: controlling the busbar cross connection switch to open to make the No. 1 AC distribution board and the No. 2 AC distribution board run independently; controlling the No. 1 daily reverse branch, the No. 2 daily reverse branch, the No. 1 battery branch and the No. 2 battery branch to be all turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in the discharging state, and the No. 1 generator set and the No. 2 generator set are both in the shutdown state.

[0013] Further, the step of controlling the power system to enter the heavy load mode by the power management module comprises: controlling the busbar cross connection switch to close to make the No. 1 AC distribution board and the No. 2 AC distribution board run in parallel; when switching from the gas supplement mode or the charging mode to the heavy load mode, controlling the No. 1 unit branch, the No. 2 unit branch, the No. 1 daily reverse branch, the No. 2 daily reverse branch, the No. 1 battery branch and the No. 2 battery branch to be all turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in the floating charging state, and the No. 1 generator set and the No. 2 generator set are both in the running state; when switching from the battery mode to the heavy load mode, controlling the No. 1 daily reverse branch, the No. 2 daily reverse branch, the No. 1 battery branch and the No. 2 battery branch to be all turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in the discharging state, and the No. 1 generator set and the No. 2 generator set are both in the shutdown state.

[0014] Further, the step of controlling the power system to enter the shutdown mode by the power management module comprises: Disconnect the control circuits for Unit 1, Unit 2, Battery 1, Battery 2, Daily Reverse Circuit 1, and Daily Reverse Circuit 2, so that Lithium Battery 1, Lithium Battery 2, Generator 1, and Generator 2 are all in a shutdown state.

[0015] The above-mentioned technical solution of this application has the following advantages: The ship power system and its modular operation method for multi-task operation provided in this application decompose the ship's entire mission cycle and the operation of the power system into six modes. During the entire mission cycle, there is no need for the upper-level control system to intervene in the control of the power system. The power system can achieve self-closed-loop operation according to the mode instructions of the upper-level control system. The power system and the upper-level control system only need to exchange mode information, which greatly reduces the amount of information exchange between the upper-level control system and the power system. This effectively improves the reliability of the execution of various complex tasks of the ship and the operation of the power system, and reduces the difficulty of use for ship operators and users. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 The single-line diagram of the ship's electrical system provided in this application; Figure 2 A schematic diagram of power flow distribution under shore power mode operation of the ship's power system provided in this application; Figure 3 A schematic diagram of power flow distribution under charging mode operation of the ship's electrical system provided for this application; Figure 4 A schematic diagram of the power flow distribution under the gas replenishment mode of the ship's electrical system provided in this application; Figure 5 A schematic diagram of power flow distribution under battery mode operation of the ship's electrical system provided in this application; Figure 6 A schematic diagram of power flow distribution under heavy load mode (generator power supply) operation of the ship's electrical system provided in this application; Figure 7 This is a schematic diagram of the power flow distribution under the heavy load mode (lithium battery pack power supply) of the ship's power system provided in this application. Detailed Implementation

[0018] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and processes are omitted so as not to obscure the description of this application with unnecessary detail.

[0019] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0020] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" means "two or more."

[0022] The specific embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but are not intended to limit the scope of this application.

[0023] This application provides a shipboard power system for multi-tasking conditions, comprising a diesel generator set, a lithium battery energy storage device, a DC power distribution system (including an electric propulsion system), and an AC power distribution system. The network connection relationship of the shipboard power system is shown in [reference needed]. Figure 1 The diagram shown is a single-line diagram of the ship's electrical system.

[0024] 1) The configuration and connection relationship between the diesel generator set and the lithium battery energy storage device are as follows: The diesel generator set consists of two disc-type AC generator sets, using permanent magnet synchronous generators, with a rated power of 250kW, a rated voltage of three-phase AC 690V, and a rated frequency of 240Hz.

[0025] The lithium battery energy storage device uses two sets of lithium iron phosphate battery packs, which are independent of each other and have a total capacity of about 6300kWh. The battery pack voltage is between DC 900V and 1050V and is equipped with a battery management system, which serves as the power source for the electric propulsion device.

[0026] To accommodate the voltage levels of diesel generator sets and lithium battery energy storage devices, a 1kV DC power distribution system is adopted, connecting the diesel generator sets and lithium battery packs according to... Figure 1 The lithium battery packs are connected in parallel as shown. Lithium battery pack #1 transmits power to the 1kV DC busbar of DC distribution board #1 after dynamic current sharing via DC / DC power conversion module #1. Lithium battery pack #2 transmits power to the 1kV DC busbar of DC distribution board #2 after dynamic current sharing via DC / DC power conversion module #2. Similarly, generator set #1 transmits power to the 1kV DC busbar of DC distribution board #1 after rectification via AC / DC power conversion module #1. Generator set #2 transmits power to the 1kV DC busbar of DC distribution board #2 after rectification via AC / DC power conversion module #2.

[0027] 2) The configuration and connection relationships of the DC power distribution system (including the electric propulsion device) are as follows: like Figure 1 As shown, the DC power distribution system includes DC power distribution board No. 1, DC power distribution board No. 2, electric propulsion device No. 1, and electric propulsion device No. 2.

[0028] The No. 1 DC distribution board includes one 1kV DC busbar, one 300kW DC / DC power conversion module, one 250kW DC / AC power conversion module, one 250kW AC / DC power conversion module, and one power management module. The AC / DC power conversion module is responsible for converting the 690V AC power generated by the generator set into 1kV DC power to supply the DC bus, and has constant current and voltage limiting, and constant voltage and current limiting charging functions. The DC / DC power conversion module is responsible for converting the fluctuating DC power from 900V to 1050V generated by the lithium battery pack into 1kV stable voltage DC power to supply the DC bus, and has constant current and voltage limiting, and constant voltage and current limiting charging functions. The DC / AC power conversion module is responsible for inverting the 1kV DC power into 620V, 50Hz three-phase AC power, and has an inverter soft start function for supplying AC daily loads. The power management module is used to control the operating mode of the entire ship's power system (including power start-up and shutdown and power distribution), and can receive power system operating mode request commands from the upper control system, while simultaneously feeding back the power system operating status monitoring quantities and alarm quantities to the upper control system in real time.

[0029] The technical specifications of DC distribution board No. 2 are exactly the same as those of DC distribution board No. 1, including one 1kV DC busbar, one 300kW DC / DC power conversion module, one 250kW DC / AC power conversion module, one 250kW AC / DC power conversion module, and one power management module. The power management module of DC distribution board No. 2 is interconnected with the power management module of DC distribution board No. 1 via Gigabit Ethernet, providing hot backup for each other. The power management module of either DC distribution board can control the operating mode of the entire ship's power system.

[0030] Both Electric Propulsion Unit 1 and Electric Propulsion Unit 2 have a rated power of 95kW. Each electric propulsion unit consists of a propulsion motor and a propulsion frequency converter. A failure in either electric propulsion unit will not affect the normal operation of the other. Each electric propulsion unit uses a dual power supply with automatic switching. The propulsion motor adopts a 6-phase design, and can continue operating at reduced power in the event of a single Y-winding failure.

[0031] DC distribution board No. 1 and DC distribution board No. 2 operate independently and serve as redundant backups for each other.

[0032] The 1kV DC busbar of DC distribution board No. 1 is connected to the No. 1 propulsion frequency converter via the No. 1 propulsion DC busbar fuse, providing the main power supply for the No. 1 electric propulsion unit. The 1kV DC busbar of DC distribution board No. 1 is connected to the No. 2 propulsion frequency converter via the No. 2 propulsion DC busbar fuse, providing the backup power supply for the No. 2 electric propulsion unit. When the main power supply to the No. 2 electric propulsion unit is lost, it automatically switches to the backup power supply. The 1kV DC busbar of DC distribution board No. 2 is connected to the No. 2 propulsion frequency converter via the No. 2 propulsion DC busbar fuse, providing the main power supply for the No. 2 electric propulsion unit. The 1kV DC busbar of DC distribution board No. 2 is connected to the No. 1 propulsion frequency converter via the No. 1 propulsion DC busbar fuse, providing the backup power supply for the No. 1 electric propulsion unit. When the main power supply to the No. 1 electric propulsion unit is lost, it automatically switches to the backup power supply.

[0033] 3) The configuration and connection relationships of the AC power distribution system are as follows: like Figure 1 As shown, the AC power distribution system includes No. 1 isolation transformer, No. 2 isolation transformer, No. 1 day-use transformer, No. 2 day-use transformer, No. 1 AC distribution board, and No. 2 AC distribution board.

[0034] Both isolation transformer No. 1 and isolation transformer No. 2 have a turns ratio of three-phase AC 620V / 400V, a rated capacity of 315kVA, and a rated frequency of 50Hz. They are used to achieve electrical isolation and voltage matching between the household inverter power supply and the AC distribution board.

[0035] Both No. 1 and No. 2 day-use transformers have a turns ratio of AC 400V / 230V, a rated capacity of 50kVA, and a rated frequency of 50Hz. They are used for voltage matching to supply power to single-phase AC 220V equipment. The capacity of either day-use transformer can meet the power requirements of all 220V equipment on the ship.

[0036] AC distribution board No. 1 receives AC power from DC distribution board No. 1 and distributes power to AC 380V and AC 220V equipment. AC distribution board No. 2 receives AC power from DC distribution board No. 2 and distributes power to AC 380V and AC 220V equipment. The specific connection is as follows: The 1kV DC busbar of DC distribution board No. 1 is inverted into 620V, 50Hz three-phase AC power via a DC / AC power conversion module. This is further converted to 400V, 50Hz three-phase AC power by isolation transformer No. 1, and then supplied to the 400V AC busbar of AC distribution board No. 1 to power AC 380V equipment. The 400V AC busbar of AC distribution board No. 1 is connected to the 230V AC power supply of AC distribution board No. 1 via a utility transformer No. 1. The 1kV DC busbar of the No. 2 DC distribution board is converted into 620V, 50Hz three-phase AC power by the DC / AC power conversion module, and further converted into 400V, 50Hz three-phase AC power by the No. 2 isolation transformer. The 400V AC busbar of the No. 2 AC distribution board supplies power to the 380V AC equipment. The 400V AC busbar of the No. 2 AC distribution board is connected to the 230V AC busbar of the No. 2 AC distribution board via the No. 2 day-use transformer.

[0037] There are tie switches QF2 and QF4 between AC distribution board 1 and AC distribution board 2, which are used to connect the 400V AC busbar of AC distribution board 1 and the 400V AC busbar of AC distribution board 2. During normal operation, both QF2 and QF4 are closed. In addition, the 400V AC busbar of AC distribution board 2 is divided into two by busbar jumper switch QF5. During normal operation, busbar jumper switch QF5 can be opened or closed as needed to realize the segmented operation or parallel operation of the two AC distribution boards.

[0038] The main power supply branches of the ship's electrical system are named as follows: The branch from generator set No. 1 through AC / DC power conversion module No. 1 to the 1kV DC bus of DC distribution board No. 1 is denoted as generator set No. 1 branch. The branch from generator set No. 2 through AC / DC power conversion module No. 2 to the 1kV DC bus of DC distribution board No. 2 is denoted as generator set No. 2 branch. The branch from lithium battery pack No. 1 through DC / DC power conversion module No. 1 to the 1kV DC bus of DC distribution board No. 1 is denoted as battery branch No. 1. The branch from lithium battery pack No. 2 through DC / DC power conversion module No. 2 to the 1kV DC bus of DC distribution board No. 2 is denoted as battery branch No. 2. The branch from the 1kV DC busbar of DC distribution board No. 1 through DC / AC power conversion module No. 1 and isolation transformer No. 1 to the 400V AC busbar of AC distribution board No. 1 is called the No. 1 day reverse branch. The branch from the 1kV DC busbar of the No. 2 DC distribution board through the No. 2 DC / AC power conversion module and the No. 2 isolation transformer to the 400V AC busbar of the No. 2 AC distribution board is called the No. 2 day reverse branch.

[0039] The following is combined with Figures 2 to 7 The present application provides a more detailed description of a modular operation method for a ship's power system oriented towards multi-task conditions.

[0040] The modular operation method for ship power systems oriented towards multiple mission conditions proposed in this application involves the power management module controlling the ship's power system to operate in any one of the following modes according to instructions from the upper-level control system: shore power mode, charging mode, gas replenishment mode, battery mode, heavy load mode, and shutdown mode. Based on instructions from the upper-level control system and the ship's current mission condition, the power management module controls the power system to enter the operating mode corresponding to that mission condition. The correspondence between ship mission conditions and power system operating modes is as follows: shore power mode, charging mode, gas replenishment mode, battery mode, heavy load mode, and shutdown mode correspond to six major mission conditions: berthing and preparation for navigation, high-speed navigation with diesel engine propulsion, gas cylinder replenishment, low-speed navigation with electric propulsion, a high-power task, and personnel onboard maintenance operations, respectively. Each power system operating mode can fully meet the power demand under its corresponding mission condition.

[0041] Power flow distribution is crucial for power system operation and control. In this embodiment, combined with... Figures 2 to 7 The paper presents typical power flow distributions of the ship's power system under shore power mode, charging mode, gas replenishment mode, battery mode, and heavy load mode in the modular operation method of the ship's power system of this application, so as to intuitively reflect the output of each power source, the power flow direction of each branch, and the load power of each 230V AC bus and 400V AC bus in the above operation modes of the power system.

[0042] A) Shore power mode The shore power mode of a ship's electrical system refers to the operating mode in which the ship relies on shore power to supply power to its daily AC loads at the dock and to recharge its lithium battery energy storage devices when it is moored at the pier. In shore power mode, the shore power switch SC-K connected to the 400V AC busbar of AC distribution board No. 2 automatically closes, and the busbar jumper switch QF5 automatically closes, allowing AC distribution boards No. 1 and No. 2 to operate in parallel. Simultaneously, all switches on the No. 1 and No. 2 reverse daily circuits, battery circuits No. 1 and No. 2 automatically close, both lithium battery banks are charging, and both generator sets are shut down. Before entering shore power mode, the shore power cable must be manually connected to the ship's AC shore power socket when AC distribution board No. 2 is de-energized. The maximum operating current of the shore power socket is three-phase AC 380V / 50Hz / 250A.

[0043] Typical power flow distribution of shore power mode in ship electrical systems is as follows: Figure 2 As shown, shore power supplies inject 105.3kW of power into the ship's electrical system. The 230V AC busbar of AC distribution board 1 has a load power of 20.7kW, the 230V AC busbar of AC distribution board 2 has a load power of 20.7kW, the 400V AC busbar of AC distribution board 1 has a load power of 6.9kW, the 400V AC busbar of AC distribution board 2 has a load power of 6.9kW, and the charging power of each lithium battery pack is 23kW.

[0044] When a vessel enters the berthing and preparation mode, the power management module follows these steps to enter shore power mode according to instructions from the higher-level control system: 1) When the power management module is powered on, it changes from a power-off state to a normal power-on working state, and the upper-level control system receives the default "battery mode feedback" from the power management module. 2) The upper control system sends a "shutdown mode request" command to the power management module. The upper control system receives a "shutdown mode feedback" from the power management module (ensure that the 400V AC busbar of AC distribution board No. 2 connected to shore power is de-energized before connecting to shore power). 3) The upper-level control system sends a "shore power mode request" command to the power management module; 4) The upper control system receives the "shore power mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "shore power switch SC-K closing feedback", "No. 1 unit branch operation stopped", "No. 2 unit branch operation stopped", "No. 1 battery branch charging status", "No. 2 battery branch charging status", "No. 1 day reverse branch operation", "No. 2 day reverse branch operation", "busbar jumper switch QF5 closing feedback".

[0045] B) Charging Mode The charging mode of the ship's electrical system refers to the simultaneous operation of two generator sets when the ship is propelled by the diesel main engine at high speed. Each generator set charges two lithium battery packs via a DC distribution board, while simultaneously transmitting power from the DC distribution boards to two AC distribution boards, supplying power to all 380V and 220V AC equipment on board. In charging mode, because a portion of the generator's power is used to charge the lithium battery packs, the power available to all AC equipment on board is limited, only meeting the ship's navigation power requirements and not suitable for starting high-power loads. In charging mode, the bus jumper switch QF5 automatically disconnects, allowing AC distribution boards 1 and 2 to operate independently. Simultaneously, all switches on the following branches automatically close: Day / Reverse Branch 1, Day / Reverse Branch 2, Battery Branch 1, Battery Branch 2, Generator Branch 1, and Generator Branch 2. Both lithium battery packs are charging, and both generator sets are operating.

[0046] Typical power flow distribution of the charging mode of a ship's electrical system is as follows: Figure 3 As shown, generator sets 1 and 2 each generate 250kW of power, lithium battery packs 1 and 2 each have a charging power of 126kW, the 230V AC busbars of AC distribution boards 1 and 2 each carry a load of 27.3kW, the 400V AC busbar of AC distribution board 1 carries a load of 61.3kW, the 400V AC busbar BUS-B of AC distribution board 2 carries a load of 81.8kW, and the 400V AC busbar BUS-C of AC distribution board 2 carries a load of 20.5kW.

[0047] After the vessel completes its berthing and preparation for navigation, it enters the high-speed navigation mode propelled by the diesel engine. The power management module switches from shore power mode to charging mode according to the instructions of the upper control system as follows: 1) The upper control system sends a "shutdown mode request" command to the power management module. The upper control system receives a "shutdown mode feedback" from the power management module (ensure that the shore power cable is disconnected only when the 400V AC busbar of AC distribution board No. 2 connected to shore power switch SC-K is de-energized). 2) After receiving the "shutdown mode feedback" and the shore power cable is disconnected, the upper control system sends a "charging mode request" command to the power management module. 3) The upper control system receives the "charging mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "Unit 1 branch is in operation", "Unit 2 branch is in operation", "Charging status of Battery 1 branch", "Charging status of Battery 2 branch", "Daily reverse branch of Unit 1 is in operation", "Daily reverse branch of Unit 2 is in operation".

[0048] C) Qi Replenishment Mode The gas replenishment mode of a ship's electrical system refers to a floating charge state where the ship's two lithium battery packs are neither charging nor discharging. Two generator sets provide sufficient power as the ship's main power source to ensure the operation of the high-power, high-voltage air compressors and thus complete the gas replenishment task. In gas replenishment mode, because the lithium battery packs require less power in the floating charge state, the power generated by the two generator sets is mainly used to supply the loads connected to the AC switchboards. Therefore, compared to the charging mode, the electrical system in gas replenishment mode can meet greater power demands and ensure the normal operation of the high-voltage air compressors connected to the two AC switchboards to complete the gas replenishment task. In gas replenishment mode, the busbar jumper switch QF5 automatically disconnects, allowing AC switchboards 1 and 2 to operate independently. Simultaneously, all switches on the 1st generator branch, 2nd generator branch, 1st day reverse branch, 2nd day reverse branch, 1st battery branch, and 2nd battery branch automatically close.

[0049] Typical power flow distribution of the gas replenishment mode of a ship's electrical system is as follows: Figure 4 As shown, generator sets 1 and 2 each generate 250kW of power, lithium battery packs 1 and 2 each have a grid-connected float charging power of 10kW, the 230V AC busbars of AC distribution boards 1 and 2 each carry a load of 57.4kW, the 400V AC busbar of AC distribution board 1 carries a load of 129.1kW, the 400V AC busbar BUS-B of AC distribution board 2 carries a load of 172.2kW, and the 400V AC busbar BUS-C of AC distribution board 2 carries a load of 43.1kW.

[0050] When the ship enters the air cylinder replenishment task mode, the power management module enters the replenishment mode according to the instructions from the upper control system as follows: 1) The upper-level control system sends a "gas replenishment mode request" command to the power management module; 2) The upper control system receives the "gas replenishment mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "Unit 1 branch is running", "Unit 2 branch is running", "Unit 1 day reverse branch is running", "Unit 2 day reverse branch is running", "Battery 1 branch is running", "Battery 2 branch is running", "Battery 1 branch is not charging", "Battery 2 branch is not charging", "Battery 1 branch is not discharging", "Battery 2 branch is not discharging".

[0051] D) Battery Mode The battery mode of a ship's electrical system refers to a system operation mode in which the ship shuts down both generator sets and the high-speed diesel engine, and starts two lithium battery banks to power the two electric propulsion units and other equipment, relying on electric propulsion to maintain low-speed navigation. In battery mode, the power that the two battery banks can supply to the rest of the ship's equipment is limited, in addition to powering the two electric propulsion units, and it is not suitable for starting high-power loads. In battery mode, the bus jumper switch QF5 automatically disconnects, allowing AC distribution boards 1 and 2 to operate independently. At the same time, all switches on the 1st and 2nd day / reverse branches, the 1st and 2nd battery branches automatically close, both lithium battery banks are in a discharging state, and both generator sets are in a stopped state.

[0052] Typical power flow distribution in battery mode of ship electrical systems is as follows: Figure 5 As shown, the discharge power of lithium battery packs 1 and 2 is 300kW each, the power absorbed by electric propulsion devices 1 and 2 is 95kW each, the load power of the 230V AC busbars of AC distribution boards 1 and 2 is 48.3kW each, the load power of the 400V AC busbar of AC distribution board 1 is 108.5kW, the load power of the 400V AC busbar BUS-B of AC distribution board 2 is 144.7kW, and the load power of the 400V AC busbar BUS-C of AC distribution board 2 is 36.2kW.

[0053] When the ship enters a low-speed navigation mission using electric propulsion, the power management module enters battery mode according to the instructions from the higher-level control system as follows: 1) The upper-level control system sends a "battery mode request" command to the power management module; 2) The upper control system receives the "battery mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "Discharge status of battery branch 1", "Discharge status of battery branch 2", "Daily reverse branch 1 in operation", "Daily reverse branch 2 in operation", "Branch 1 of unit 1 in operation stopped", "Branch 2 of unit 2 in operation stopped".

[0054] E) Overload mode The heavy-load mode of a ship's electrical system refers to the operating mode when a ship urgently needs to switch from a refueling mission, a low-speed electric propulsion mission, or a high-speed diesel engine propulsion mission to a high-power mission. In this mode, the power supply (two generator sets or two lithium battery packs) from the previous operating mode is used to power the entire ship, and the two AC switchboards are connected in parallel to provide greater power. If switching from refueling mode or charging mode to heavy-load mode, the two generator sets continue to power the entire ship, and the two lithium battery packs are in a floating charge state, neither charging nor discharging. All switches on generator set branch 1, generator set branch 2, reverse current branch 1, reverse current branch 2, battery branch 1, and battery branch 2 are automatically closed. If switching from battery mode to heavy-load mode, the two lithium battery packs continue to power the entire ship, the two generator sets remain off, and all switches on reverse current branch 1, reverse current branch 2, battery branch 1, and battery branch 2 are automatically closed. In heavy-load mode, the bus jumper switch QF5 automatically closes to connect AC distribution board 1 and AC distribution board 2 in parallel. The power fed by the two DC distribution boards is collected into the 400V AC busbar of the parallel AC distribution board to ensure the execution of high-power tasks.

[0055] Typical power flow distribution of a ship's electrical system under heavy load mode (generator power supply) is as follows: Figure 6 As shown, generator sets 1 and 2 each generate 250kW of power, lithium battery packs 1 and 2 each have a grid-connected floating charging power of 10kW, the 230V AC busbars of AC distribution boards 1 and 2 each carry a load of 57.4kW, the 400V AC busbar of AC distribution board 1 carries a load of 139.2kW, and the 400V AC busbar of AC distribution board 2 carries a load of 205.2kW.

[0056] Typical power flow distribution of a ship's electrical system under heavy load mode (lithium battery pack power supply) is as follows: Figure 7 As shown, the discharge power of lithium battery pack No. 1 and lithium battery pack No. 2 is 240kW. The load power of the 230V AC busbars of AC distribution boards No. 1 and No. 2 is 57.4kW. The load power of the 400V AC busbar of AC distribution board No. 1 is 139.2kW, and the load power of the 400V AC busbar of AC distribution board No. 2 is 205.2kW.

[0057] When a ship transitions from a refueling operation or a high-speed diesel engine propulsion operation to a high-power operation, the power management module switches from refueling mode or charging mode to heavy-load mode according to instructions from the upper control system, as follows: 1) The upper-level control system sends a "reload mode request" command to the power management module; 2) The upper control system receives the "heavy load mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "Unit 1 branch is running", "Unit 2 branch is running", "Unit 1 day reverse branch is running", "Unit 2 day reverse branch is running", "Unit 1 battery branch is running", "Unit 2 battery branch is running", "Unit 1 battery branch is not charging", "Unit 2 battery branch is not charging", "Unit 1 battery branch is not discharging", "Unit 2 battery branch is not discharging", "Bus bridge switch QF5 closing feedback".

[0058] When a ship transitions from a low-speed, electric-propelled navigation mission to a high-power mission, the power management module switches from battery mode to heavy-load mode according to instructions from the upper-level control system, as follows: 1) The upper-level control system sends a "reload mode request" command to the power management module; 2) The upper control system receives the "heavy load mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "No. 1 day reverse branch operation", "No. 2 day reverse branch operation", "No. 1 battery branch discharge", "No. 2 battery branch discharge", "No. 1 unit branch operation stop", "No. 2 unit branch operation stop", "bus bridge switch QF5 closing feedback".

[0059] F) Power off mode The shutdown mode of a ship's electrical system refers to a power system operation mode in which, to ensure personnel safety during shore maintenance or other onboard operations, both generator sets and two lithium battery packs are shut down, and major electrical equipment is turned off. Communication between the power management module and the upper-level control system is maintained solely through the ship's uninterruptible power supply (UPS). In shutdown mode, all 1kV DC busbars, 400V AC busbars, and 230V AC busbars on the ship are de-energized.

[0060] The power flow distribution in the shutdown mode of the ship's electrical system is as follows: the output of the generator set and the lithium battery pack are both 0, the power on all primary power supply branches of the ship's electrical system is 0, and the voltage of all 1kV DC busbars, 400V AC busbars and 230V AC busbars is 0.

[0061] When the ship enters the onboard maintenance operation mode, the power management module enters the shutdown mode according to the instructions of the superior control system as follows: 1) The upper-level control system sends a "shutdown mode request" command to the power management module; 2) The upper control system receives the "shutdown mode feedback" from the power management module, and at the same time receives the following characteristic feedback signals: "Day reverse branch No. 1 stops running", "Day reverse branch No. 2 stops running", "Battery branch No. 1 stops running", "Battery branch No. 2 stops running", "Unit No. 1 branch stops running", "Unit No. 2 branch stops running".

[0062] The ship power system and its modular operation method for multi-task operation provided in this application decompose the ship's entire mission cycle and the operation of the power system into six modes. During the ship's entire mission cycle, there is no need for the upper-level control system to intervene in the control of the power system. The power system can achieve self-closed-loop operation according to the mode instructions of the upper-level control system. The power system and the upper-level control system only need to exchange mode information, which greatly reduces the amount of information exchange between the upper-level control system and the power system. This effectively improves the reliability of the execution of various complex tasks of the ship and the operation of the power system, and reduces the difficulty of use for ship operators and users.

[0063] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application.

[0064] It should be clarified that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. This application is not limited to the specific structures described above and shown in the figures. Furthermore, for the sake of brevity, detailed descriptions of known methods and techniques are omitted here.

[0065] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A shipboard electrical system for multi-task operation, characterized in that, This includes diesel generator sets, lithium battery energy storage devices, DC power distribution systems, and AC power distribution systems. The diesel generator set includes generator set 1 and generator set 2, and the lithium battery energy storage device includes lithium battery pack 1 and lithium battery pack 2. The DC power distribution system includes DC distribution board No. 1 and DC distribution board No. 2; DC distribution board No. 1 includes a 1kV DC busbar, DC / DC power conversion module No. 1, DC / AC power conversion module No. 1, AC / DC power conversion module No. 1, and power management module; DC distribution board No. 2 includes a 1kV DC busbar, DC / DC power conversion module No. 2, DC / AC power conversion module No. 2, AC / DC power conversion module No. 2, and power management module. The AC power distribution system includes a No. 1 isolation transformer, a No. 2 isolation transformer, a No. 1 AC distribution board, and a No. 2 AC distribution board; the No. 1 AC distribution board includes a 400V AC busbar, and the No. 2 AC distribution board includes a 400V AC busbar and a shore power box, wherein the shore power box is connected to the 400V AC busbar of the No. 2 AC distribution board via a shore power switch; The No. 1 generator set is connected to the 1kV DC bus of the No. 1 DC distribution board via the No. 1 AC / DC power conversion module, forming the No. 1 generator set branch; the No. 2 generator set is connected to the 1kV DC bus of the No. 2 DC distribution board via the No. 2 AC / DC power conversion module, forming the No. 2 generator set branch. The No. 1 lithium battery pack is connected to the 1kV DC bus of the No. 1 DC distribution board via the No. 1 DC / DC power conversion module, forming the No. 1 battery branch; the No. 2 lithium battery pack is connected to the 1kV DC bus of the No. 2 DC distribution board via the No. 2 DC / DC power conversion module, forming the No. 2 battery branch. The 1kV DC bus of the No. 1 DC distribution board is connected to the 400V AC busbar of the No. 1 AC distribution board via the No. 1 DC / AC power conversion module and the No. 1 isolation transformer, forming the No. 1 daily reverse branch; the 1kV DC bus of the No. 2 DC distribution board is connected to the 400V AC busbar of the No. 2 AC distribution board via the No. 2 DC / AC power conversion module and the No. 2 isolation transformer, forming the No. 2 daily reverse branch. The power management module is used to control the power system to enter the operating mode corresponding to the mission condition according to the instructions of the upper control system and the mission condition of the ship. At the same time, it provides real-time feedback of the power system operating status monitoring and alarm quantities to the upper control system. A connecting switch is provided between AC distribution board No. 1 and AC distribution board No. 2 to connect the 400V AC busbar of AC distribution board No. 1 and the 400V AC busbar of AC distribution board No. 2; the 400V AC busbar of AC distribution board No. 2 is divided into two by a busbar jumper switch to realize the segmented operation or parallel operation of AC distribution board No. 1 and AC distribution board No.

2.

2. The shipboard power system for multi-task operation as described in claim 1, characterized in that, The DC power distribution system also includes a No. 1 electric propulsion device and a No. 2 electric propulsion device; the No. 1 electric propulsion device includes a No. 1 propulsion motor and a No. 1 propulsion frequency converter, and the No. 2 electric propulsion device includes a No. 2 propulsion motor and a No. 2 propulsion frequency converter; The 1kV DC busbar of the No. 1 DC distribution board is connected to the No. 1 propulsion frequency converter via the No. 1 propulsion DC busbar fuse to provide the main power supply for the No. 1 electric propulsion device; the 1kV DC busbar of the No. 1 DC distribution board is connected to the No. 2 propulsion frequency converter via the No. 2 propulsion DC busbar fuse to provide the backup power supply for the No. 2 electric propulsion device. The 1kV DC busbar of the No. 2 DC distribution board is connected to the No. 2 propulsion frequency converter via the No. 2 propulsion DC busbar fuse to provide the main power supply for the No. 2 electric propulsion device; the 1kV DC busbar of the No. 2 DC distribution board is connected to the No. 1 propulsion frequency converter via the No. 1 propulsion DC busbar fuse to provide the backup power supply for the No. 1 electric propulsion device.

3. The shipboard power system for multi-task operation as described in claim 1, characterized in that, The AC power distribution system also includes a No. 1 day-use transformer and a No. 2 day-use transformer; the No. 1 AC distribution board also includes a 230V AC busbar, and the No. 2 AC distribution board also includes a 230V AC busbar; The 400V AC busbar of AC distribution board No. 1 is connected to the 230V AC busbar of AC distribution board No. 1 via the No. 1 daytime transformer, and the 400V AC busbar of AC distribution board No. 2 is connected to the 230V AC busbar of AC distribution board No. 2 via the No. 2 daytime transformer.

4. A modular operation method for a ship's power system oriented towards multi-task operating conditions, characterized in that, Based on the ship electric power system for multi-task operation described in any one of claims 1 to 3; The modular operation method for ship electric power systems oriented towards multi-task conditions includes the following steps: Based on the instructions of the superior control system and the ship's mission conditions, the power management module controls the power system to enter the operating mode corresponding to the mission conditions. The mission conditions include berthing and preparation for navigation, high-speed navigation propelled by diesel engine, replenishment of air cylinders, low-speed navigation propelled by electric propulsion, a high-power mission, and personnel boarding the ship for maintenance operations. The corresponding power system operation modes include shore power mode, charging mode, replenishment of air mode, battery mode, heavy load mode, and shutdown mode.

5. The modular operation method for ship power systems oriented towards multi-task operating conditions as described in claim 4, characterized in that, The steps for the power management module to control the power system to enter shore power mode include: The shore power switch connected to the 400V AC busbar of AC distribution board No. 2 is closed, and the busbar jumper switch is closed to enable AC distribution board No. 1 and AC distribution board No. 2 to operate in parallel. Control the No. 1 day reverse branch, the No. 2 day reverse branch, the No. 1 battery branch, and the No. 2 battery branch to all be turned on, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in a charging state, and the No. 1 generator set and the No. 2 generator set are both in a shutdown state.

6. The modular operation method for ship power systems oriented towards multi-task conditions as described in claim 4, characterized in that, The steps by which the power management module controls the power system to enter charging mode include: The control bus jumper switch is disconnected to allow AC distribution board No. 1 and AC distribution board No. 2 to operate independently; Control the No. 1 day reverse branch, No. 2 day reverse branch, No. 1 battery branch, No. 2 battery branch, No. 1 generator branch, and No. 2 generator branch to ensure that both No. 1 and No. 2 lithium battery packs are in a charging state, and both No. 1 and No. 2 generator sets are in an operating state.

7. The modular operation method for ship power systems oriented towards multi-task operating conditions as described in claim 4, characterized in that, The steps for the power management module to control the power system to enter the gas replenishment mode include: The control bus jumper switch is disconnected to allow AC distribution board No. 1 and AC distribution board No. 2 to operate independently; The control circuits for Unit 1, Unit 2, Reverse Flow 1, Reverse Flow 2, Battery 1, and Battery 2 are all connected, so that both Lithium Battery 1 and Lithium Battery 2 are in float charging state, and both Generator 1 and Generator 2 are in operation state.

8. The modular operation method for ship power systems oriented towards multi-task conditions as described in claim 4, characterized in that, The steps by which the power management module controls the power system to enter battery mode include: The control bus jumper switch is disconnected to allow AC distribution board No. 1 and AC distribution board No. 2 to operate independently; Controlling the No. 1 day reverse branch, the No. 2 day reverse branch, the No. 1 battery branch, and the No. 2 battery branch all to conduct, so that the No. 1 lithium battery pack and the No. 2 lithium battery pack are both in a discharge state, and the No. 1 generator set and the No. 2 generator set are both in a shutdown state.

9. The modular operation method for ship power systems oriented towards multi-task conditions as described in claim 4, characterized in that, The steps for the power management module to control the power system to enter heavy load mode include: The control bus jumper switch is closed to enable AC distribution board No. 1 and AC distribution board No. 2 to operate in parallel. When switching from gas replenishment mode and charging mode to heavy load mode, the control circuits of Unit 1, Unit 2, Daily reverse circuit 1, Daily reverse circuit 2, Battery 1, and Battery 2 are all turned on, so that both Lithium Battery 1 and Lithium Battery 2 are in float charging state, and both Generator 1 and Generator 2 are in operation state. When switching from battery mode to heavy load mode, control circuits 1 and 2, battery circuit 1 and battery circuit 2 are all turned on, so that lithium battery pack 1 and lithium battery pack 2 are both in a discharge state, and generator set 1 and generator set 2 are both in a shutdown state.

10. The modular operation method for ship power systems oriented towards multi-task conditions as described in claim 4, characterized in that, The steps for the power management module to control the power system to enter shutdown mode include: Disconnect the control circuits for Unit 1, Unit 2, Battery 1, Battery 2, Daily Reverse Circuit 1, and Daily Reverse Circuit 2, so that Lithium Battery 1, Lithium Battery 2, Generator 1, and Generator 2 are all in a shutdown state.

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