Trailing suction dredger power system and control method thereof

Abstract

According to the power system of the trailing suction dredger and the control method of the power system, the system comprises a main power module, a storage battery module, a main distribution circuit board and an execution terminal of the trailing suction dredger, and the storage battery module is connected with the input end of the main distribution circuit board through a power distribution switch; the main power module comprises an engine, an adjustable pitch propeller and an axle generator, and the engine is connected with the adjustable pitch propeller and the axle generator through a one-inlet two-outlet gearbox. A storage battery module comprising two storage battery packs is arranged in a main power distribution system, configuration of a power system and a power system is optimized, the power storage battery pack is automatically charged when the load of the main power module is used too low, and the power storage battery pack automatically supplies power to a power grid when the load of the main power module is used too high. The functions of peak load shifting, host operation load stabilizing and host installation power and energy consumption reducing are achieved, and full-automatic intelligent control over the battery management module in the charging and discharging process of the energy storage power storage battery pack is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ship power systems, and more specifically, to a power system of a trailing suction dredger and a control method thereof. Background Art

[0002] In recent years, as the capacity of the suction hopper dredger has become larger and larger, in order to meet the dredging and navigation performance requirements of the ship, the main engine power has also become larger and larger. In the prior art, large dredgers mostly adopt a "one-to-two" drive mode, that is, each main diesel engine drives an adjustable pitch propeller (CPP) and an AC shaft-driven main generator (shaft generator). In the conditions of navigation, dredging and shore discharge, the main engine power must be reasonably allocated to the propeller and the power system to achieve the best dredging output and energy consumption ratio. The power of the main engine needs to be configured according to the use requirements of the extreme conditions, usually according to the power requirements of the shore blowing condition, while the actual operating conditions of the dredger are more, and the switching between the conditions is more frequent. The operating load of the main engine varies greatly. In the dredging and loading and light-load navigation stages, the load of the main engine is low, and in the heavy-load navigation and shore blowing stages, the load of the main engine is high. The use of too high or too low load will result in high fuel consumption of the diesel engine and shortened maintenance cycles.

[0003] Patent document CN202863752U discloses a power device for a trailing suction dredger, which includes a first main engine and a second main engine, wherein the flywheel end of the first main engine is respectively connected to a first shaft-belt generator and a first adjustable pitch propeller through a first main propulsion gearbox, and the output end of the first shaft-belt generator is respectively connected to a first side thruster, a first high-pressure water pump and a first underwater mud pump through a first power distribution system; the flywheel end of the second main engine is respectively connected to a second shaft-belt generator and a second adjustable pitch propeller through a second main propulsion gearbox, and the output end of the second shaft-belt generator is respectively connected to a second side thruster, a second high-pressure water pump and a second underwater mud pump through a second power distribution system; the main engine load and utilization rate of the dredger under its main working conditions are both in an ideal state, the operating cost of the ship is reduced, the operation and control of the ship are simpler and more convenient, the working environment of the crew is improved, the ship equipment that needs to be repaired is reduced, the failure rate of the ship is reduced, and the economy of the ship is improved in many aspects. However, the complex working conditions of the trailing suction hopper dredger were not considered. When the load power is high, the engine runs at full load, and the engine fuel consumption is high at this time, which does not solve the fuel economy problem of the ship.

[0004] Patent document CN213677103U discloses that by setting up a battery pack, a motor and a first converter, it is possible to achieve zero emissions and zero pollution without starting the main engine for driving when approaching or leaving the port area, meeting the emission requirements of the port area. At the same time, by setting up the first converter and the battery pack, it is possible to provide propulsion power while storing and utilizing the electric energy generated by the motor during power generation, which is more economical and environmentally friendly. This patent document considers the use of battery packs to improve fuel economy, but its scenario is only to start the battery pack without starting the main engine, and does not consider how to solve the problem of engine fuel economy when starting the main engine.

[0005] Therefore, the existing design method of the power unit of the trailing suction hopper dredger has certain technical defects, which is difficult to adapt to the use requirements of the large-scale and complex and changeable operating conditions of the trailing suction hopper dredger, and is not in line with the development direction of green dredging and intelligent dredging. Summary of the invention

[0006] The present invention provides a trailing suction dredger power system and a control method thereof, so as to solve the problem that the existing dredger power system configuration cannot perform load balancing according to the complex working procedures of the dredger, resulting in high fuel consumption of the diesel engine and not conforming to green dredging and intelligent dredging. Through the coordinated regulation of the power distribution switch and the battery management module, the main power module is always operated under the economic load, thereby improving the overall fuel economy.

[0007] According to one aspect of the present invention, a power system of a trailing suction hopper dredger is provided, comprising a main power module, a battery module, a main distribution circuit board and an execution terminal of the trailing suction hopper dredger, wherein the battery module is connected to the input end of the main distribution circuit board through a distribution switch; the main power module comprises an engine, an adjustable pitch propeller, a power management module and a shaft generator, wherein the engine is respectively connected to the adjustable pitch propeller and the shaft generator through a one-input and two-output gearbox, the power management module is connected to the main distribution circuit board to monitor and manage the power of each module in the system, the main power module is two, and the shaft generator of each main power module is respectively connected to the input end of the main distribution circuit board through a distribution switch, the execution terminal is connected to the output end of the main distribution circuit board through the distribution switch, the power of the system is monitored and managed through the power management module, and the engine in the main power module is always operated under economic load by the coordinated regulation of the distribution switch and the battery management module.

[0008] Preferably, based on the above scheme, the battery module includes a battery pack and a transformer, the battery pack is arranged in two groups in parallel and is connected to the transformer through a frequency converter, and the transformer is connected to the main distribution circuit board through a distribution switch.

[0009] Preferably, based on the above solution, a main control switch is further provided between the power distribution switches at the output ends of the two battery packs, and the main power modules are respectively provided at both ends of the main control switch.

[0010] Preferably, based on the above solution, the battery module includes a battery management module, and the battery management modules are respectively connected to the battery pack control.

[0011] Preferably, based on the above scheme, the execution terminal is one or more of a side thrust motor, a high-pressure water pump motor, an underwater mud pump motor and an in-cabin mud pump motor.

[0012] The present invention also provides a control method for the power system of a trailing suction dredger, comprising monitoring the load power of the execution terminal through a power management module, when the load power of the execution terminal is less than 40% of the rated output power of the whole ship, the distribution switch connects the shaft belt engine in one of the two groups of power modules to the input end of the main distribution board, and at the same time, the distribution switch connects the two groups of batteries to the input end of the main distribution board, starts the engine connected to the input end side of the main distribution board, and the engine drives the shaft belt generator to work to supply power to the load of the terminal, the battery management module controls the two groups of battery groups to be in a charging state, stores the excess electric energy in the system in the battery groups, regulates the power consumption condition of the system, so that the engine is maintained in an optimal condition, when the load power of the execution terminal is between 40% and 69% of the rated output power of the whole ship, the above-mentioned single engine is maintained to work continuously, and the battery management module controls the two groups of battery groups to discharge to the main distribution board to supplement the system The power supply gap is filled, and the power consumption condition of the system is regulated so that the engine is maintained in the best working condition. When the load power of the execution terminal is between 70% and 80% of the rated output power of the whole ship, the distribution switch connects all the two shaft generators in the two power modules to the input end of the main distribution board, starts the two engines to drive the shaft generators to supply power to the load of the terminal, and disconnects the two battery groups from the main distribution board through the distribution switch. At this time, the engine is in the best working condition as a whole. When the load power of the execution terminal is greater than 80% of the rated output power of the whole ship, the distribution switch connects the two battery groups to the input end of the main distribution board, and controls the two battery groups to discharge to the main distribution board through the battery management module to supplement the system power supply gap, regulate the power consumption condition of the system, and maintain the engine in the best working condition. Through the coordinated regulation of the distribution switch and the battery management module, the engine of the main power module is always running under economic load.

[0013] Based on the above scheme, it is preferred that the battery module completes one charge and discharge within one dredging cycle to achieve "peak shaving and valley filling" for the main power module.

[0014] Based on the above scheme, the battery is preferably one or more of a lead-acid battery, a lithium-ion battery, and a sodium-ion battery.

[0015] A power system for a trailing suction dredger of the present invention is provided with a battery module including two battery groups in a main power distribution system, the configuration of the power system and the electric power system is optimized, the power battery group is automatically charged when the load usage of the main power module is relatively low, and when the load usage of the main power module is relatively high, the power battery group automatically supplies power to the power grid, so as to achieve the effects of shaving peaks and filling valleys, stabilizing the operating load of the main engine, and reducing the installed power and energy consumption of the main engine. The charging and discharging process of the energy storage power battery group is fully automatically and intelligently controlled by the battery management module.

[0016] Compared with the prior art, the present invention is a simple-structured, energy-saving, and efficient trailing suction dredger power system and control method. Due to the adoption of the above technology, the positive and beneficial effects produced are:

[0017] 1. Effectively stabilize the use load of the ship engine 1, so that it can run in an economic load state under different operating conditions, and the operating state is stable. When the load on the execution end is low, only one engine is started, and the charging and discharging of the battery pack is controlled by the charging and discharging module to further improve the fuel economy of the system. When the execution load is high, by starting two engines at the same time, and coordinating with the battery pack, the system is energy-controlled, so that the engine is always in the best working condition, reducing fuel consumption and improving fuel economy. The coordinated control of the distribution switch and the battery management module enables the main power module to always operate under the economic load, improve the overall fuel economy, optimize the fuel utilization rate, improve the economic benefits of the ship, reduce exhaust emissions, and achieve energy conservation and emission reduction;

[0018] 2. The power management module, the switch of the power module and the switch of the battery module are integrated into the main distribution board, which saves the volume of the system, makes the system more integrated, and is also convenient for maintenance;

[0019] 3. The ultimate dredging capacity of the ship is improved. Under extreme working conditions, the engine 1 and the battery pack 11 can simultaneously supply power to the main switchboard 5, thereby improving the dredging performance under the condition that the installed power remains unchanged. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1It is a structural schematic diagram of the power system of the trailing suction dredger of the present invention;

[0022] Description of Figure Numbers:

[0023] Engine 1; one-inlet and two-outlet gearbox 2; adjustable pitch propeller 3; shaft generator 4; main switchboard 5; distribution switch 6; power management module 7; battery management module 8; transformer 9; frequency converter 10; battery pack 11; thrust motor 12; high-pressure flushing pump motor 13; selection switch 14; underwater mud pump motor 15; in-cabin mud pump motor 16. DETAILED DESCRIPTION

[0024] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0025] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections.

[0026] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0027] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0028] In the embodiments shown in the drawings, the indications of directions (such as up, down, left, right, front and back) used to explain the structure and movement of the various components of the present invention are not absolute but relative. These descriptions are appropriate when these components are in the positions shown in the drawings. If the descriptions of the positions of these components change, the indications of these directions also change accordingly.

[0029] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0031] See also Figure 1 As shown, a power system of a trailing suction hopper dredger of the present invention comprises a main power module, a battery module, a main distribution circuit board, a power management module and an execution terminal of the trailing suction hopper dredger, wherein the battery module is connected to the input end of the main distribution circuit board through a distribution switch 6; the main power module comprises an engine 1, an adjustable pitch propeller 3 and a shaft generator 4, wherein the engine 1 is respectively connected to the adjustable pitch propeller 3 and the shaft generator 4 through a one-input and two-output gearbox 2, wherein the power management module 7 is connected to the main distribution circuit board 5 to monitor and manage the power of each module in the system, wherein the main power module is two, and the shaft generator 4 of each main power module is respectively connected to the input end of the main distribution circuit board through a distribution switch 6, wherein the execution terminal is connected to the output end of the main distribution circuit board through the distribution switch 6, wherein the power management module is used to monitor and manage the power of the system, and wherein the distribution switch and the battery management module are used to coordinately control the engine of the main power module so that the engine of the main power module is always operated under an economic load.

[0032] The battery module of the present invention includes a battery pack 11 and a transformer 9 . The battery pack 11 is arranged in two groups in parallel and is connected to the transformer 9 through a frequency converter 10 . The transformer 9 is connected to the main distribution circuit board through a distribution switch 6 .

[0033] Engine 1 is the power source of the entire ship. It releases mechanical energy through fuel combustion. The mechanical energy released by engine 1 drives the adjustable pitch propeller 3 and the shaft generator 4 through the one-inlet and two-outlet gearbox 2; the shaft generator 4 provides electricity to the entire ship through the distribution board. The load of engine 1 is determined by the load of the adjustable pitch propeller 3 and the shaft generator 4.

[0034] The main power module drives the adjustable pitch propeller 3 and the shaft generator 4 simultaneously. Since the frequencies of the two shaft generators 4 of the main power module cannot be kept synchronized, the main switchboard 5 is divided into two sections separated by the distribution switch 6. Each section is connected to a shaft generator 4, a battery pack 11 and half of the dredging equipment of the whole ship.

[0035] That is, a main control switch is further arranged between the power distribution switches 6 at the output ends of the two storage battery groups 11, and the main power modules are respectively arranged at both ends of the main control switch.

[0036] The execution terminal of the present invention is one or more of the side thrust motor 12, the high pressure flushing pump motor 13, the selection switch 14, the underwater mud pump motor 15 and the cabin mud pump motor 16.

[0037] That is to say, the equipment connected to each section of the main distribution board 5 includes the thrust motor 12, the high-pressure water pump motor 13, and the mud pump motor, among which the underwater mud pump motor 15 and the cabin mud pump motor 16 will not be used at the same time, and can be powered by the same variable frequency drive system through the selection switch 14.

[0038] Each section of the main distribution board 5 is connected to a set of battery packs 11 through a transformer 9 and an inverter 10, and the charging and discharging of the battery packs are determined according to the usage load of the main machine.

[0039] Specifically, the battery module of the present invention includes a battery management module 8, and the battery management module 8 is respectively connected to the battery pack 11 for controlling the charging and discharging of the battery pack.

[0040] For ease of understanding, the working state of the present invention is described below;

[0041] The high-power loads of the electric system of the trailing suction hopper dredger of the present invention are mainly the in-cabin mud pump, underwater mud pump and high-pressure flushing pump. There are large differences in the power required for the mud pump under the conditions of dredging and loading, shore discharge and filling. Generally, in the dredging and loading condition, the underwater mud pump works; in the condition of pumping out the cabin and discharging from the shore, the in-cabin mud pump works; in the condition of pumping out the cabin and discharging from the shore, the engine 1 must provide more power to the power system to meet the needs of the in-cabin mud pump for pumping out the cabin and discharging from the shore, and under certain complex environmental conditions, the engine 1 also needs to provide power for the CPP and / or side thruster to resist the external environmental force and maintain the position of the ship. At this time, the power of the main diesel engine may not meet the needs of the CPP and the power station, thereby affecting the efficiency of the in-cabin mud pump for pumping out the cabin and discharging from the shore; and in the conditions of dredging and sailing, the main diesel engine running in the best state has a certain amount of surplus power in addition to providing the power required for the ship to propel the CPP and the power of the shaft generator 4.

[0042] In view of the characteristics of each typical working condition, the present invention proposes a control method for a power system of a trailing suction hopper dredger. In addition to the conventional engine 1 driving an adjustable pitch propeller 3 and a shaft generator 4 through a gearbox in a "one-to-two" configuration, a battery pack 11 is connected to the main switchboard 5. When the electric power required on board is less and the load of the engine 1 is lower, the battery is charged. At this time, the battery pack 11 is used as user electricity. Under the working condition that the electric power required on board is larger and the load of the engine 1 is higher, the battery pack 11 is discharged to supply power to the main switchboard 5. At this time, the battery pack 11 is used as a power source together with the shaft generator 4 to supply power to the main switchboard 5. Through this design, the load clock of the engine 1 can be operated at the optimal working point, the fuel consumption per unit power is the lowest, and the emission index is the best. At the same time, under the condition that the installed power of the whole ship is limited, through the compensation of the battery, the power output of the power station can exceed the maximum power of the diesel engine, thereby improving the dredging performance of the dredger. That is, under the condition that the power required by the whole ship is certain, the installed power of the whole ship can be effectively reduced, and the performance index of the dredger can be effectively improved.

[0043] The present invention also provides a control method for the power system of a trailing suction dredger, comprising: monitoring the load power of the execution terminal through a power management module, when the load power of the execution terminal is less than 40% of the rated output power of the whole ship, the distribution switch connects the shaft belt engine in one of the two groups of power modules to the input end of the main distribution board, and at the same time, the distribution switch connects the two groups of batteries to the input end of the main distribution board, starts the engine connected to the input end side of the main distribution board, and the engine drives the shaft belt generator to work to supply power to the load of the terminal, the battery management module controls the two groups of battery groups to be in a charging state, stores the excess electric energy in the system in the battery groups, regulates the power consumption condition of the system, so that the engine is maintained in an optimal condition, and when the load power of the execution terminal is between 40% and 69% of the rated output power of the whole ship, the above-mentioned single engine is maintained to work continuously, and the battery management module controls the two groups of battery groups to discharge to the main distribution board to supplement the system The power supply gap is filled, and the power consumption condition of the system is regulated so that the engine is maintained in the best working condition. When the load power of the execution terminal is between 70% and 80% of the rated output power of the whole ship, the distribution switch connects all the two shaft generators in the two power modules to the input end of the main distribution board, starts the two engines to drive the shaft generators to supply power to the load of the terminal, and disconnects the two battery groups from the main distribution board through the distribution switch. At this time, the engine is in the best working condition as a whole. When the load power of the execution terminal is greater than 80% of the rated output power of the whole ship, the distribution switch connects the two battery groups to the input end of the main distribution board, and controls the two battery groups to discharge to the main distribution board through the battery management module to supplement the system power supply gap, regulate the power consumption condition of the system, and maintain the engine in the best working condition. Through the coordinated regulation of the distribution switch and the battery management module, the engine of the main power module is always running under economic load.

[0044] In the present invention, within one dredging cycle, the storage battery module completes one charge and discharge, thereby realizing "peak shaving and valley filling" for the main power module.

[0045] The storage battery is one or more of a lead-acid battery, a lithium-ion battery, and a sodium-ion battery.

[0046] The working conditions of the trailing suction dredger of the present invention mainly include: light-load navigation, at this time it is mainly from the mud throwing operation area to the dredging area, at this time the ship has a shallow draft, the dredging equipment does not work, and the load of the engine 1 is relatively low; dredging and loading, at this time the ship's speed is low, the propeller, in addition to driving the ship to sail at a low speed, also needs to provide traction to overcome the incidental resistance of the drag head, and at the same time the engine 1 drives the shaft belt generator 4 to supply power to the main switchboard 5 to drive the mud pump, high-pressure flushing pump and other dredging equipment, and the load of the engine 1 is relatively high; heavy-load navigation, when the mud tank is full After that, the ship puts away the drag head, stops the mud pump and high-pressure flushing pump, and sails to the mud discharge area. At this time, the draft of the ship is deep, the resistance is large, and the load of the engine 1 is relatively high; mud throwing, after arriving at the mud throwing area, the ship reduces the speed and opens the mud door, so that the mud in the mud tank is discharged to the seabed by gravity. At this time, the load of the engine 1 is relatively low; shore blowing and shore discharge, the mud pump discharges the mud in the mud tank to the shore through rainbow blowing or taking over. At this time, the load of the propeller is low, and the capacity of the engine 1 is mainly used by the dredging equipment through the shaft belt generator 4, and the load is relatively high.

[0047] In light-load navigation conditions, the load of the engine 1 is relatively low. At this time, the surplus power of the four shaft-belt generators can be used to charge the battery pack 11; in dredging and loading conditions, the operating load of the engine 1 is slightly different depending on the dredging conditions such as soil quality and flow rate. Whether the battery pack 11 supplies power to the distribution board can be determined based on the operating load of the engine 1; in the heavy-load navigation stage, the appropriate speed is usually selected based on the economic load of the engine 1, and the battery pack 11 does not need to work; in shore blowing and shore discharge conditions, in order to improve dredging efficiency, the mud pump usually runs at the limit load. At this time, the battery pack 11 supplies power to the distribution board, cooperating with the four shaft-belt generators to meet the energy needs of the dredging equipment.

[0048] A power system for a trailing suction dredger of the present invention is provided with a battery module including two battery groups 11 in a main power distribution system, the power system and the electric power system configuration are optimized, the power battery group 11 is automatically charged when the load of the main power module is low, and the power battery group 11 automatically supplies power to the power grid when the load of the main power module is high, so as to achieve the effects of shaving peaks and filling valleys, stabilizing the operating load of the engine 1, and reducing the installed power and energy consumption of the engine 1. The charging and discharging process of the energy storage power battery group 11 is fully automatically and intelligently controlled by the battery management module.

[0049] Compared with the prior art, the present invention is a simple-structured, energy-saving, and efficient trailing suction dredger power system and control method. Due to the adoption of the above technology, the positive and beneficial effects produced are:

[0050] 1. Effectively stabilize the use load of the ship engine 1, so that it can run in an economic load state under different operating conditions, and the operating state is stable. When the load on the execution end is low, only one engine is started, and the system is controlled by the charging and discharging module of the battery pack to further improve the fuel economy of the system. When the execution load is high, by starting two engines at the same time, and coordinating with the battery pack, the system is energy-controlled, so that the engine is always in the best working condition, reducing fuel consumption and improving fuel economy. The coordinated control of the distribution switch and the battery management module enables the main power module to operate under the economic load all the time, improving the overall fuel economy, optimizing the fuel utilization rate, improving the economic benefits of the ship, reducing exhaust emissions, and achieving energy conservation and emission reduction;

[0051] 2. The power management module, the switch of the power module and the switch of the battery module are integrated into the main distribution board, which saves the volume of the system, makes the system more integrated, and is also convenient for maintenance;

[0052] 3. The ultimate dredging capacity of the ship is improved. Under extreme working conditions, the engine 1 and the battery pack 11 can simultaneously supply power to the main switchboard 5, thereby improving the dredging performance under the condition that the installed power remains unchanged.

[0053] Finally, the method of the present application is only a preferred implementation scheme and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A power system of a trailing suction dredger, characterized in that: The invention comprises a main power module, a battery module, a main distribution circuit board, a power management module and an execution terminal of a trailing suction dredger, wherein the battery module is connected to the input end of the main distribution circuit board through a power distribution switch, and the power management module is electrically connected to the main distribution circuit board to monitor and manage the power of each module in the system; the main power module comprises an engine, an adjustable pitch propeller and a shaft-belt generator, and the engine is respectively connected to the adjustable pitch propeller and the shaft-belt generator through a one-inlet and two-outlet gearbox, the main power module is two, and the shaft-belt generator of each main power module is respectively connected to the input end of the main distribution circuit board through a power distribution switch, the execution terminal is connected to the output end of the main distribution circuit board through a power distribution switch, the power of the system is monitored and managed through the power management module, and the engine of the main power module is always operated under economic load by the coordinated regulation of the power distribution switch and the battery management module.

2. A power system for a trailing suction hopper dredger according to claim 1, characterized in that: The battery module includes a battery pack, a frequency converter and a transformer. The battery pack is arranged in two groups in parallel and is connected to the transformer through the frequency converter. The transformer is connected to the main distribution circuit board through a distribution switch.

3. A power system for a trailing suction hopper dredger as claimed in claim 2, characterized in that: A main control switch is also provided between the distribution switches at the output ends of the two battery packs. The main power modules are respectively provided at both ends of the main control switch, operate in separate grids, and can be connected to the grid for a short time for load transfer.

4. A power system for a trailing suction hopper dredger as claimed in claim 2, characterized in that: The battery module includes a battery management module, and the battery management modules are respectively connected to the battery pack control.

5. A power system for a trailing suction hopper dredger as claimed in claim 2, characterized in that: The execution terminal is one or more of a thrust motor, a high-pressure water pump motor, an underwater mud pump motor and an in-cabin mud pump motor.

6. A method for controlling a power system of a trailing suction hopper dredger according to any one of claims 1 to 5, characterized in that: The invention comprises monitoring the load power of the execution terminal through a power management module. When the load power of the execution terminal is less than 40% of the rated output power of the whole ship, the distribution switch connects the shaft belt engine in one of the two power modules to the input end of the main distribution board, and at the same time, the distribution switch connects the two battery groups to the input end of the main distribution board, starts the engine connected to the input end side of the main distribution board, and the engine drives the shaft belt generator to work to supply power to the load of the terminal. The battery management module controls the two battery groups to be in a charging state, stores the excess electric energy in the system in the battery groups, regulates the power consumption of the system, and maintains the engine in the best working condition. When the load power of the execution terminal is between 40% and 69% of the rated output power of the whole ship, the single engine is maintained to work continuously, and the two battery groups are controlled by the battery management module to discharge to the main distribution board to supplement the power supply gap of the system, and regulates the power consumption of the system. condition, so that the engine is maintained in the best working condition. When the load power of the execution terminal is between 70% and 80% of the rated output power of the whole ship, the distribution switch connects all the two groups of the shaft generators in the two power modules to the input end of the main distribution board, starts the two groups of engines to drive the shaft generators to supply power to the load of the terminal, and disconnects the two groups of battery groups from the main distribution board through the distribution switch. At this time, the engine is in the best working condition as a whole. When the load power of the execution terminal is greater than 80% of the rated output power of the whole ship, the distribution switch connects the two groups of batteries to the input end of the main distribution board, and controls the two groups of batteries to discharge to the main distribution board through the battery management module, supplements the system power supply gap, and regulates the system power consumption condition, so that the engine is maintained in the best working condition. Through the coordinated regulation of the distribution switch and the battery management module, the engine of the main power module is always running under economic load.

7. The control method of the power system of a trailing suction hopper dredger according to claim 6, characterized in that: In one dredging cycle, the battery module completes a charging and discharging cycle, achieving "peak shaving and valley filling" for the main power module.

8. The control method of the power system of a trailing suction hopper dredger according to claim 6, characterized in that: The battery is one or more of a lead-acid battery, a lithium-ion battery, and a sodium-ion battery.

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