CN112249291A

CN112249291A - Control method of fuel cell unit for ship and hybrid electric propulsion system

Info

Publication number: CN112249291A
Application number: CN202010973271.0A
Authority: CN
Inventors: 张小玉; 王希炜; 刘博�; 桂勇
Original assignee: China Shipbuilding Power Engineering Institute Co Ltd
Current assignee: China Shipbuilding Power Engineering Institute Co Ltd
Priority date: 2020-09-16
Filing date: 2020-09-16
Publication date: 2021-01-22
Anticipated expiration: 2040-09-16
Also published as: CN112249291B

Abstract

The embodiment of the invention discloses a control method of a fuel cell unit for a ship and a hybrid electric propulsion system, wherein the method comprises the following steps: controlling to start the corresponding fuel cell according to the fuel cell starting number; determining the working state of the fuel cell, determining the target output power of the fuel cell according to the power requirement, and acquiring the actual output power of the fuel cell through a fuel cell controller; judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling the DC/DC converter; and controlling to close the corresponding fuel cell according to the fuel cell closing number. According to the technical scheme provided by the embodiment of the invention, an appropriate energy distribution strategy is formulated by combining the working state of the fuel cell, so that effective energy conservation and emission reduction are realized.

Description

Control method of fuel cell unit for ship and hybrid electric propulsion system

Technical Field

The embodiment of the invention relates to the technical field of ship power supplies, in particular to a control method of a fuel cell unit for a ship and a hybrid electric propulsion system.

Background

The ships are used as main transportation means at sea, and higher requirements are put on the research of a power supply system and a power supply strategy of the ships.

Currently, a hybrid power supply system is proposed, which includes a plurality of power modules connected in series, each of the power modules includes a fuel cell unit and a lithium ion battery unit, and the fuel cell unit and the lithium ion battery unit are connected in parallel. The lithium ion battery units respectively carry out charging and discharging management on the lithium ion battery units through respective fuel battery units, so that the hybrid power supply system cannot plan the working states of all the fuel battery units to make a proper energy distribution strategy, and cannot achieve effective energy conservation and emission reduction.

Disclosure of Invention

The embodiment of the invention provides a control method of a fuel cell unit for a ship and a hybrid electric propulsion system, which are used for formulating a proper energy distribution strategy by combining the working state of a fuel cell so as to realize effective energy conservation and emission reduction.

In a first aspect, an embodiment of the present invention provides a method for controlling a fuel cell unit for a ship, where the ship includes a plurality of fuel cell units, each fuel cell unit is connected to an integrated energy management module, and the integrated energy management module is configured to control power supply of a fuel cell in the fuel cell unit, and the method includes:

determining a fuel cell starting number, and controlling to start a corresponding fuel cell according to the fuel cell starting number;

determining the working state of the fuel cell, determining the target output power of the fuel cell according to the power requirement, and acquiring the actual output power of the fuel cell through a fuel cell controller; wherein the operating conditions include steady state and transient state;

judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel battery is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the fuel cell;

and determining the fuel cell closing number, and controlling to close the corresponding fuel cell according to the fuel cell closing number.

Optionally, the power supply module further includes a hydrogen supply unit, and the hydrogen supply unit includes a hydrogen system controller and a plurality of hydrogen cylinder groups; the fuel cell controller of each fuel cell and the hydrogen system controller are connected with a comprehensive energy management unit;

the controlling and starting the corresponding fuel cell according to the fuel cell starting number comprises the following steps:

the integrated energy management unit transmits the fuel cell starting number to the hydrogen system controller;

the hydrogen system controller controls to open the corresponding valve of the hydrogen cylinder group according to the opening number of the fuel cell;

the hydrogen system controller judges whether the valve of the corresponding hydrogen cylinder group is opened successfully; if the operation is not successful, feeding back a hydrogen cylinder group opening failure signal to the comprehensive energy management unit; the integrated energy management unit transmits a next fuel cell start number to the hydrogen system controller; if successful, then

Feeding back a hydrogen cylinder group opening success signal to the comprehensive energy management unit; and after receiving the successful opening signal of the hydrogen cylinder group, the comprehensive energy management unit sends an opening instruction signal to the corresponding fuel cell controller according to the opening number of the fuel cell.

Optionally, the method of sending an opening instruction signal to the corresponding fuel cell controller according to the fuel cell opening number further includes:

the fuel cell controller judges whether the fuel cell is started successfully within a preset time; if the current is successful, controlling the fuel cell to output current; if not successful, then

Feeding back a fuel cell starting failure signal to the comprehensive energy management unit; the integrated energy management unit re-sends the turn-on command signal to the fuel cell controller.

Optionally, after the integrated energy management unit sends the start instruction signal to the fuel cell controller again, the method further includes:

and the comprehensive energy management unit judges whether the frequency of sending the starting instruction information is within a preset frequency, and controls to start another fuel cell if the frequency exceeds the preset frequency.

Optionally, the adjusting the output power of the fuel cell to the target output power by controlling a DC/DC converter connected thereto includes:

the integrated energy management unit determines the change rate of the output power of the fuel cell according to the target output power, the actual power and the transient setting time, and transmits a power signal calculated correspondingly to a DC/DC controller of a DC/DC converter;

the DC/DC controller controls the DC/DC converter to regulate the output power of the fuel cell according to the power signal.

Optionally, after the DC/DC controller controls the DC/DC converter to adjust the output power of the fuel cell according to the power signal, the method further includes:

and the comprehensive energy management unit receives the actual output power of the fuel cell fed back by the fuel cell controller, judges whether the actual output power of the fuel cell keeps up with the target output power within the transient set time, and increases the set transient time if the actual output power of the fuel cell does not keep up with the target output power.

Optionally, the transient setting time is not more than 10 seconds.

Optionally, the determining a fuel cell shutdown number and controlling to shut down the corresponding fuel cell according to the fuel cell shutdown number includes:

the comprehensive energy management unit controls to close the fuel cells through a fuel cell controller according to the fuel cell closing numbers and controls DC/DC converters connected with the fuel cells in a one-to-one correspondence manner to reduce output power to zero;

the fuel cell controller feeds back a shutdown signal to the comprehensive energy management unit;

and the comprehensive energy management unit transmits a closing valve signal to the hydrogen system controller according to the shutdown signal so as to control to close the hydrogen cylinder group supplying hydrogen to the fuel cell.

Optionally, after the fuel cell controller feeds back a shutdown signal to the integrated energy management unit, the method further includes:

and controlling to stop the action of a proportional regulating valve arranged on a pipeline between the fuel cell and the hydrogen cylinder group.

In a second aspect, an embodiment of the present invention provides a hybrid electric propulsion system, including an energy integrated management module, and further including a plurality of fuel cell units, where each fuel cell unit is connected to the energy integrated management module, and the energy integrated management module is configured to control fuel cells in the fuel cell units, including determining a fuel cell start number, and controlling to start a corresponding fuel cell according to the fuel cell start number; the fuel cell controller is also used for determining the target output power of the fuel cell in real time according to the power requirement and acquiring the actual output power of the fuel cell through the fuel cell controller; judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the fuel cell; and the controller is used for determining the fuel cell closing number and controlling to close the corresponding fuel cell according to the fuel cell closing number.

The embodiment of the invention provides a control method of a fuel cell unit for a ship and a hybrid electric propulsion system, wherein the hybrid electric propulsion system comprises a plurality of fuel cell units and an energy comprehensive management module, each fuel cell unit is connected with the energy comprehensive management module, and the control method comprises the following steps: determining a fuel cell opening number, and controlling to open the corresponding fuel cell according to the fuel cell opening number; determining the working state of the fuel cell, determining the target output power of the fuel cell according to the power requirement, and acquiring the actual output power of the fuel cell through a fuel cell controller; wherein the operating conditions include steady state and transient state; judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the fuel cell; and determining the fuel cell closing number, and controlling to close the corresponding fuel cell according to the fuel cell closing number. According to the technical scheme provided by the embodiment of the invention, an appropriate energy distribution strategy is formulated by combining the working state of the fuel cell, so that effective energy conservation and emission reduction are realized.

Drawings

FIG. 1 is a block diagram of a hybrid electric propulsion system according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the connections between the controllers of the hybrid electric propulsion system of FIG. 1;

FIG. 3 is a block diagram of another hybrid electric propulsion system provided in accordance with an embodiment of the present invention;

FIG. 4 is a block diagram of another hybrid electric propulsion system provided in accordance with an embodiment of the present invention;

FIG. 5 is a flowchart of a method for starting a hybrid electric propulsion system according to an embodiment of the present invention;

fig. 6 is a flowchart of a control method of a marine battery unit according to an embodiment of the present invention;

FIG. 7 is a voltage graph of a marine battery according to an embodiment of the present invention;

fig. 8 is a flowchart of a control method of a marine fuel cell unit according to an embodiment of the present invention;

FIG. 9 is a flowchart of the method shown in FIG. 8 for each of the steps in step S310;

FIG. 10 is another flow chart of the method of FIG. 8 for each of the steps in step S310;

FIG. 11 is a flowchart of the method shown in FIG. 8 for each of the steps in step S330;

fig. 12 is a flowchart of another control method for a marine fuel cell unit according to an embodiment of the present invention;

fig. 13 is a control strategy diagram of a marine fuel cell unit under non-mode control according to an embodiment of the present invention;

fig. 14 is a schematic view of the start-up level of a marine fuel cell unit under non-mode control according to an embodiment of the present invention;

fig. 15 is a schematic diagram of the number of fuel cell units for a ship that are turned on under non-mode control according to an embodiment of the present invention;

fig. 16 is a flowchart of a control method of a marine fuel cell unit under mode control according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It is to be further noted that, for the convenience of description, only a part of the structure relating to the present invention is shown in the drawings, not the whole structure.

An embodiment of the present invention provides a hybrid electric propulsion system, and fig. 1 is a block diagram of a structure of a hybrid electric propulsion system provided in an embodiment of the present invention, and with reference to fig. 1, includes:

a start switch 110 for generating a start signal according to input start information;

the uninterruptible power supply unit 120 is connected with the starting switch 110 and is used for supplying power to the storage battery unit 12, the fuel battery unit 11 and the energy comprehensive management module 30 according to the starting signal so as to enable the storage battery unit 12, the fuel battery unit 11 and the energy comprehensive management module 30 to complete self-checking;

the energy comprehensive management module 30 is connected with the starting switch 110, and is used for acquiring self-checking result information of the storage battery unit 12 and the fuel cell unit 11 after receiving the starting signal, and judging whether the hybrid electric propulsion system meets the starting condition or not by combining the self-checking result information;

a mode selection unit 80 connected to the energy integrated management module 30, for selecting a start mode and generating a corresponding mode signal according to the start mode; the energy comprehensive management module 30 is further configured to start the battery unit 12 and the fuel cell unit 11 according to the mode signal, and allocate energy outputs of the battery unit 12 and the fuel cell unit 11;

the battery unit 12 and the fuel cell unit 11 are both connected to the dc bus L, and the battery unit 12 and the fuel cell unit 11 are used to supply power to the dc bus L to supply power to the load 40.

Specifically, the power system on the ship includes a power supply side and a power consumption side, wherein the power supply side is the hybrid power propulsion system, and the power consumption side is the load 40 on the ship. For example, the marine load 40 may include cabin machinery, deck machinery, marine lighting, navigation equipment, ac propulsion motors, and other point of use equipment. The power supply side comprises a power supply module 10 for providing electric energy and an energy comprehensive management module 30 for allocating energy output of the power supply module 10. The hybrid electric propulsion system includes an activation switch 110, and the activation switch 110 may generate an activation signal based on input activation information. The integrated energy management module 30 is connected to the start switch 110, and may be electrically connected or communicatively connected. For example, the start switch 110 is a start button on the ship, when the start button is pressed, information transmission between the integrated energy management module 30 and the start switch 110 is performed, and the integrated energy management module 30 may receive a start signal of the hybrid electric propulsion system on the ship. The hybrid electric propulsion System further includes an Uninterruptible Power supply (USP) unit 120, and the ups unit 120 is connected to the start switch 110, and may be electrically connected or communicatively connected. The ups unit 120 supplies power to the battery unit 12, the fuel cell unit 12, and the energy integrated management module according to the received start signal, so that the battery unit 12, the fuel cell unit 11, and the energy integrated management module 30 complete self-testing. The uninterruptible power supply unit 120 supplies weak current to the storage battery unit 12, the fuel cell unit 11 and the energy comprehensive management module 30, and thus the self-checking of the system is satisfied. The purpose is to acquire the states of the fuel cell unit 11 and the storage battery unit 12 in the power supply module 10 on the ship and the state of the energy integrated management module 30, determine whether the starting condition of the hybrid electric propulsion system is met according to the fed-back self-checking information, and ensure that the system can be started safely.

The Planned Maintenance System (PMS) refers to a set of detailed periodic Maintenance plans made by a shipman according to the requirements of the current specifications of the China Classification Society (CCS) and the specifications of the equipment manufacturer, and the ship machinery (including electrical equipment) is always kept in a good technical state through the penetration and implementation of the plans on the ship. The energy integrated management module 30 may be a set of computer application systems that are based on a shared database, respectively operate on a ship and a shore-based computer system, and have five functions of Plan Maintenance System (PMS) management, ship spare part management, basic database management, engineering report management, ship-shore data exchange, and the like.

The mode selection unit 80 is used for selecting a starting mode and generating a corresponding mode signal according to the starting mode; the energy integrated management module 30 is also used for starting the storage battery unit 12 and the fuel battery unit 11 according to the mode signal; the storage battery unit 12 and the fuel cell unit 11 are connected with the energy comprehensive management module 30, and the energy comprehensive management module 30 starts the storage battery unit 12 and the fuel cell unit 11 according to the mode signal and allocates the energy output of the storage battery unit 12 and the fuel cell unit 11; the battery unit 12 and the fuel cell unit 11 are used to supply power to the dc bus L to supply power to the load 40.

The energy comprehensive management module in the embodiment of the invention is connected with the power supply module, and can adjust the energy output of the fuel cell unit and the storage battery unit according to the mode signal or the speed signal. When the ship is in different working modes, mode signals corresponding to the different working modes can be sent to the energy comprehensive management module, and at the moment, the energy comprehensive management module regulates energy output of the fuel cell unit and the storage battery unit according to the received mode signals and the power requirement of the load. The energy output of the fuel cell unit and the energy output of the storage battery unit are allocated through the energy comprehensive management module according to the mode signal or the speed signal, the stability of the power system is improved, the self-checking of the power system is completed before the power system is started, the safety of the power system is improved, the service characteristics and the service life of devices on the ship are guaranteed, and the effects of energy conservation and emission reduction are improved.

Optionally, the starting mode includes a parking mode, an entering and exiting port mode, a sailing mode and a half-speed mode; the integrated energy management module 30 is further configured to schedule the energy outputs of the battery unit 12 and the fuel cell unit 11 according to a parking mode control strategy to cause the hybrid electric propulsion system to enter a parking mode when the parking mode is selected, schedule the energy outputs of the battery unit 12 and the fuel cell unit 11 according to an harbor-in mode control strategy to cause the hybrid electric propulsion system to enter a harbor-in mode when the harbor-in mode is selected, schedule the energy outputs of the battery unit 12 and the fuel cell unit 11 according to a cruise mode control strategy to cause the hybrid electric propulsion system to enter a cruise mode when the cruise mode is selected, and schedule the energy outputs of the battery unit 12 and the fuel cell unit 11 according to a half-speed mode control strategy to cause the hybrid electric propulsion system to enter a half-speed mode when the half-speed mode is selected.

Alternatively, fig. 2 is a schematic diagram of the connection relationship between the controllers in the hybrid electric propulsion system shown in fig. 1; referring to fig. 1-2, further includes converter units connected between the dc bus L and the fuel cell units 11 and between the dc bus L and the battery unit 12 in a one-to-one correspondence; the fuel cell unit 11 includes a fuel cell 111 and a fuel cell controller 112, the battery unit includes a battery 121 and a battery controller 122, the converter unit includes a DC/DC converter and a DC/DC controller; the fuel cell controller 112, the battery controller 122 and the DC/DC controller are all connected with the energy comprehensive management module;

an uninterruptible power supply unit 120 for powering up the fuel cell controller 112, the battery controller 122 and the DC/DC controller; the integrated energy management module 30 is further configured to transmit a discharging instruction to the battery controller 122 to control the battery 122 to supply power to the DC bus L after the uninterruptible power supply unit 120 powers the fuel battery controller 112, the battery controller 122, and the DC/DC controller.

Specifically, the power supply side further includes an inverter module 20 connected between the power supply module 10 and the dc bus L. The converter module 20 is used for converting the voltage input by the power supply module 10 and outputting an effective fixed voltage. The electric energy output by the power supply module 10 is converted by the converter module 20 and then provided to the dc bus L, and the load 40 on the ship obtains the working voltage through the dc bus L. A DC/AC converter unit 50 is provided between the load 40 and the DC bus L for converting the voltage on the DC bus L into the voltage required by the load 40. The power supply module 10 includes a fuel cell unit 11 and a battery unit 12, and the fuel cell unit 11 is a main propulsion power source of the ship. The battery unit 12 is used as an auxiliary energy source to compensate for the lack of dynamic characteristics of the fuel cell unit 11, and mainly plays a role in peak clipping and valley filling and stabilizing the power system.

The battery 121 is a secondary battery and can be charged and discharged. The battery 121 may be a lithium iron phosphate battery, a lithium cobalt oxide battery, a lithium manganese oxide battery, a lithium cobalt oxide battery, or a battery having a problem of difficulty in estimating the use safety and the battery power. The BATTERY controller 122 may be a BATTERY management system (BATTERY MANAGEMENT SYSTEM, BMS), and the State of Charge (S0C) of the power BATTERY pack may be accurately estimated by the BMS. The S0C value is maintained in a reasonable range, damage to the battery due to overcharge or overdischarge is prevented, and therefore the remaining energy of the energy storage battery of the hybrid electric vehicle or the state of charge of the energy storage battery is predicted at any time. The BMS may also collect voltage, temperature, charge and discharge current, and total battery voltage of the battery 121 in real time to prevent overcharge or overdischarge of the battery 121. And the battery condition can be given in time, so that the reliability and the high efficiency of the operation of the whole battery set are maintained, the utilization rate of the battery is improved, the overcharge and the over-discharge of the battery are prevented, and the service life of the battery is prolonged. The battery unit 12 includes a battery 121 and a battery controller 122, the battery controller 122 is connected to the energy integration management module 30, and the battery controller 122 is configured to transmit the state information of the battery to the energy integration management module 30 and control the energy output of the battery according to the command signal fed back from the energy integration management module 30.

The fuel cell 111 is also called an electrochemical generator, and is a chemical device that directly converts chemical energy of fuel into electric energy. The fuel cell 111 uses fuel and oxygen as raw materials, has no mechanical transmission parts, and thus has no noise pollution, emits extremely little harmful gas, and the fuel includes hydrogen fuel, biofuel, and the like. The operating conditions such as the pressure, humidity of the reaction gas, the internal humidity and temperature of the stack directly affect the performance and life of the stack. The Fuel cell controller 112(Fuel control Unit, FCU) is the control "brain" of the Fuel cell engine system, and mainly implements online detection, real-time control and fault diagnosis of the Fuel cell, thereby ensuring stable and reliable operation of the Fuel cell. The fuel cell unit 11 includes a fuel cell 111 and a fuel cell controller 112, the fuel cell controller 112 is connected to the energy integrated management module 30, and the fuel cell controller 112 is configured to transmit the state information of the fuel cell to the energy integrated management module 30 and control the energy output of the fuel cell 111 according to the instruction signal fed back by the energy integrated management module 30. The converter module 20 includes a first DC/DC converter unit 21 and a second DC/DC converter unit 22, a first end of the first DC/DC converter unit 21 being connected to the fuel cell unit 11; a second end of the first DC/DC converter unit 21 is electrically connected to the direct current bus L; a first end of the second DC/DC converter unit 22 is connected to the battery unit 12; a second end of the second DC/DC converter unit 22 is connected to the DC bus L. The integrated energy management module 30 is also connected to the converter module 20 for controlling the conduction state of the converter module 20.

After the battery controller 122 of the battery unit 12 completes the power-on and self-test, the battery 121 may be controlled to supply power to the dc bus L according to the discharging instruction transmitted by the energy integrated management module 30, so that the dc bus L has a certain amount of voltage.

Alternatively, fig. 3 is a block diagram of another hybrid electric propulsion system according to an embodiment of the present invention, and referring to fig. 2 to 3, the number of the fuel cell units 11 is plural, the number of the storage battery units 12 is plural, the fuel cell units 11 are disposed in one-to-one correspondence with the first DC/DC converter units 21, and the storage battery units 12 are disposed in one-to-one correspondence with the second DC/DC converter units 22; the first DC/DC converter unit 21 includes a unidirectional converter 211, and the second DC/DC converter unit 22 includes a bidirectional converter 221.

Specifically, the number of the fuel cell units 11 is plural, and the number of the battery unit 12 is plural, and for example, as shown in fig. 3, the hybrid electric propulsion system is composed of 4 fuel cell units 11, 2 battery units 12 having the same group capacity, 6 associated DC/DC converters, and an integrated energy management module 30. An energy management module that is redundant with the integrated energy management module 30 may be provided to serve as a backup control system when the integrated energy management module 30 is damaged. The first DC/DC converter unit 21 includes a unidirectional converter 211, and the second DC/DC converter unit includes a bidirectional converter 221. The unidirectional converter 211 and the bidirectional converter 221 are respectively provided with a DC/DC controller, and the energy integrated management module 30 controls the corresponding converter through the DC/DC controller. Since the fuel cell 111 is a power generation device and cannot store electric energy, the direction of energy transmission is not reversible, and only the unidirectional DC/DC converter 211 is required to convert and transmit energy between the fuel cell 111 and the DC bus L. Since the storage battery 122 can discharge the stored electric energy, the bidirectional DC/DC converter 221 is provided to realize bidirectional flow of energy between the storage battery 121 and the DC bus L, thereby improving the utilization rate of energy.

Optionally, referring to fig. 3, a hydrogen supply system 130 is further included, and the hydrogen supply system 130 includes a hydrogen supply unit 60 for supplying hydrogen to the fuel cell unit and a hydrogen system controller 70; the direct current bus L is used for supplying power to the hydrogen supply system 130 so that the hydrogen supply system 130 completes self-checking;

the integrated energy management module 30 is also in communication connection with the hydrogen system controller 70, and is configured to receive self-checking information of the hydrogen supply system 130 and determine whether the hydrogen supply system 130 meets a start-up condition according to the self-checking information.

Specifically, after the battery controller 122 of the battery unit 12 completes power-on and self-test, the battery 121 may be controlled to supply power to the dc bus L according to the discharging instruction transmitted by the energy integrated management module 30, so that the dc bus L has a certain amount of voltage. After the hydrogen supply system 130 obtains the voltage from the dc bus L, the self-check needs to be completed. The hydrogen supply system 130 includes a hydrogen system controller 70 through which the hydrogen supply system 130 performs self-testing. And checking whether the communication between the hydrogen system controller and the energy integrated management module is lost or not, and transmitting corresponding information to the energy integrated management module. The energy integrated management module receives the self-checking information of the hydrogen supply system 130 and judges whether the hydrogen supply system 130 meets the starting condition according to the self-checking information.

Wherein the hydrogen supply unit 60 includes a plurality of hydrogen cylinder groups 61, each hydrogen cylinder group 61 being configured to supply hydrogen gas to a pair of fuel cell units 11; the manual switch S1 is connected between the hydrogen cylinder groups 61, and the manual switch S1 is used to control the communication state between the hydrogen cylinder groups 61. Illustratively, a hybrid electric propulsion system includes 4 fuel cell units 11, and two hydrogen cylinder groups 61 are required. Each hydrogen cylinder group 61 supplies hydrogen gas to a pair of fuel cell units 11. A manual switch S1 is connected between the two hydrogen cylinder groups 61, and is used to control the communication state between the hydrogen cylinder groups 61 through the manual switch S1. So as to prevent one of the hydrogen cylinder groups 61 from being incapable of supplying gas to influence the power supply of the fuel cell unit 11, thereby improving the stability of the power system and ensuring the service characteristics and the service life of devices on the ship.

Optionally, referring to fig. 4, the system further includes a speed monitoring unit connected to the energy comprehensive management module;

the speed monitoring unit 90 is configured to generate a speed signal according to the monitored speed, and transmit the speed signal to the energy integrated management module 30; the integrated energy management module 30 is also configured to initiate the hybrid electric propulsion system into a park mode, an inbound and outbound mode, a cruise mode, or a half speed mode based on the speed signal.

Specifically, if no mode signal is input to the integrated energy management module 30, the power supply mode of the hybrid electric propulsion system of the ship may be determined by receiving the sailing speed of the ship through the integrated energy management module 30. For example, when the integrated energy management module 30 receives that the sailing speed of the ship is less than 2 knots, the output power of the power supply module is adjusted in the parking mode. When the comprehensive energy management module 30 receives that the sailing speed of the ship is greater than 2 nautical miles per hour and less than 8 nautical miles per hour, the output electric quantity of the power supply module is allocated in the port entering and exiting or half-speed mode. When the comprehensive energy management module 30 receives that the sailing speed of the ship is greater than 8 seas, the output electric quantity of the power supply module is allocated in a sailing mode. The double-protection power supply device provides double guarantee for meeting power requirements of running states and fault modes of ships, and further guarantees electric quantity requirements of ship operation. The stability of the power system is improved, the service characteristics and the service life of devices on the ship are guaranteed, and the energy-saving and emission-reducing effects are improved.

In addition, the average navigational speed of the ship within the set time period of the navigation monitored by the speed monitoring unit 90 can be used as a speed signal, so that the accuracy of the speed signal can be improved, and the working mode which is not in accordance with the actual working state of the ship is prevented from being triggered by the wrong speed signal. The stability of the power system is further improved, the service characteristics and the service life of devices on the ship are guaranteed, and the effects of energy conservation and emission reduction are improved. For example, the monitored average speed of ten minutes of ship navigation can be used as a speed signal, and the triggered working mode is ensured to be changed in time along with the change of the actual working state of the ship while the accuracy of the speed signal is ensured.

When the ship is in the berthing mode, the requirement of the ship load on the electric quantity is low, the power consumption of ship lighting or communication equipment and the like is maintained, and power is not required to be provided for the navigation of the ship. For example, when shore power is connected, the fuel cell 111 and the battery 121 stop operating, and the power source side DC/DC converter (the unidirectional converter 211 and the bidirectional converter 221) is disconnected. If no shore power is connected, when a load exists, the fuel cells 111 and the storage battery 121 are controlled to be started, the fuel cells 111 can work with the output power of 40kW, when the SOC value of the storage battery 121 is lower than 40%, the two fuel cells 111 are started, the storage battery 121 is charged, until the SOC value of the storage battery 121 reaches 50%, and one fuel cell 111 is closed.

When the ship is in the port entering and exiting mode, the ship sails at a lower ship speed or discontinuous power exists, and the requirement of ship load on electric quantity is increased. For example, when the ship is in the port entry and exit mode, the integrated energy management module 30 turns on 4 fuel cells 112 through the hydrogen system controller 70 and the fuel cell controller 112, and outputs 40kW of power by controlling the first DC/DC converter unit 211; when the SOC value of the battery 121 is lower than 50%, the output power of the fuel cell 111 is adjusted to 60kW, and when the SOC value of the battery 121 is lower than 40%, the output power of the fuel cell 111 is adjusted to 80 kW. Until the SOC of the battery 121 rises back to 55%, the output power of the fuel cell 111 decreases back to 40 kW.

When the ship is in the sailing mode, the integrated energy management module 30 controls the power supply side DC/DC converter to be closed, controls the fuel cell 111 to be the main output, and ensures that the SOC value of the battery 121 maintains a high value. For example, the battery 121 and the fuel cell 111 are all turned on, and once the SOC value of the battery 121 decreases, the power of the fuel cell 111 increases step by step, so as to ensure that the SOC value of the battery 121 is not less than 55%, wherein the maximum output power of the fuel cell 111 may be 200 kW. The integrated energy management module 30 controls the fuel cell unit 11 and the battery unit 12 of the starting part and controls the reduction of the output power demand of the load, i.e. the corresponding output power reduction according to the number of cells that can still operate.

Optionally, the integrated energy management module 30 is further configured to activate the hybrid electric propulsion system according to a set activation rule when there is no mode signal input and no speed signal input.

Specifically, the integrated energy management module 30 may control the energy output of the fuel cell unit 11 according to the SOC value of the battery unit 12, for example, determine the number of fuel cells 11 turned on and the output power.

Optionally, referring to fig. 4, the energy integrated management module 30 is further connected to the alarm module 100, and the energy integrated management module 30 is further configured to control the alarm module 100 to alarm when the abnormal condition enters the half-speed mode, and to prompt the fuel cell or the storage battery to have the damaged information.

The energy comprehensive management module is used for controlling the fuel cells in the fuel cell units, and comprises a control module and a control module, wherein the control module is used for determining the starting numbers of the fuel cells and controlling the starting of the corresponding fuel cells according to the starting numbers of the fuel cells; the fuel cell controller is also used for determining the target output power of the fuel cell in real time according to the power demand and acquiring the actual output power of the fuel cell through the fuel cell controller; judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the difference; and the controller is used for determining the fuel cell closing number and controlling to close the corresponding fuel cell according to the fuel cell closing number.

The embodiment of the invention provides a hybrid electric propulsion system, which takes a fuel cell as a main propulsion power source of a ship, takes a storage battery as an auxiliary energy source, mainly plays a role in peak clipping and valley filling, is used for making up for the deficiency of the dynamic characteristic of the fuel cell and has a function of stabilizing an electric power system. Under different states of berthing, entering and exiting ports and sailing of a ship, a strategy for reasonably distributing starting, stopping and power output of each group of fuel cells is formulated according to the charge state of the current battery system so as to meet the power requirements of the running state and the fault mode of the ship, and meanwhile, the optimal energy distribution strategy is formulated by combining the use characteristics and the service life of each product, so that the effects of energy conservation and emission reduction are achieved.

An embodiment of the present invention further provides a starting method of a hybrid electric propulsion system, fig. 5 is a flowchart of the starting method of the hybrid electric propulsion system provided in the embodiment of the present invention, and referring to fig. 5, the method includes:

and S110, the starting switch generates a starting signal according to the input starting information.

Specifically, the hybrid electric propulsion system further includes an activation switch that generates an activation signal based on the input activation information. The energy comprehensive management module is connected with the starting switch, and can be in electric connection or communication connection. For example, the start switch is a start button on the ship, when the start button is pressed, information transmission can be performed between the energy integrated management module and the start switch, and the energy integrated management module can receive a start signal of the hybrid electric propulsion system on the ship.

And S120, the uninterruptible power supply unit supplies power to the storage battery unit, the fuel cell unit and the energy comprehensive management module according to the starting signal, so that the storage battery unit, the fuel cell unit and the energy comprehensive management module complete self-checking.

Specifically, the hybrid electric propulsion System further includes an Uninterruptible Power supply (USP) unit, and the ups unit is connected to the starting switch, and may be electrically connected or communicatively connected. The uninterruptible power supply unit supplies power to the storage battery unit, the fuel cell unit and the energy comprehensive management module according to the received starting signal, so that the storage battery unit, the fuel cell unit and the energy comprehensive management module complete self-checking. The uninterruptible power supply unit supplies power to the storage battery unit, the fuel cell unit and the energy comprehensive management module as weak current, and the self-checking of the system is met. The method aims to know the states of the fuel cell unit and the lithium cell unit, determine whether the starting condition of the hybrid electric propulsion system is met or not according to the fed-back self-checking information, and guarantee that the system can be started safely.

S130, the energy comprehensive management module acquires self-checking result information of the storage battery unit and the fuel cell unit after receiving the starting signal, and judges whether the hybrid electric propulsion system meets the starting condition or not by combining the self-checking result information.

Specifically, after the uninterruptible power supply unit supplies power to the storage battery unit, the fuel cell unit and the energy comprehensive management module to enable the uninterruptible power supply unit to complete self-inspection, the energy comprehensive management module receives self-inspection information fed back by the storage battery unit and the fuel cell unit, and judges whether the current state of the fuel cell unit, the current state of the lithium cell unit and the current state of the fuel cell unit meet the condition for starting the hybrid electric propulsion system or not according to self-inspection result information.

S140, the mode selection unit selects the starting mode and generates a corresponding mode signal according to the starting mode.

Specifically, when the energy integrated management module determines that the condition for starting the hybrid electric propulsion system is satisfied, the mode selection unit selects the starting mode and generates a corresponding mode signal according to the starting mode. The start mode includes a park mode, an ingress and egress mode, a cruise mode, and a half speed mode.

And S150, the energy comprehensive management module starts the storage battery unit and the fuel cell unit according to the mode signal and allocates energy output of the storage battery unit and the fuel cell unit.

Specifically, the energy integrated management module allocates energy outputs of the battery unit and the fuel cell unit according to a parking mode control strategy when the parking mode is selected so that the hybrid electric propulsion system enters the parking mode; when the port access mode is selected, the energy output of the storage battery unit and the energy output of the fuel battery unit are adjusted according to a port access mode control strategy so that the hybrid electric propulsion system enters the port access mode; when the sailing mode is selected, the energy output of the storage battery unit and the energy output of the fuel battery unit are adjusted according to a sailing mode control strategy so that the hybrid electric propulsion system enters the sailing mode; and coordinating energy output of the battery cell and the fuel cell unit to cause the hybrid electric propulsion system to enter the half-speed mode when the half-speed mode is selected according to a half-speed mode control strategy.

And S160, supplying power to the direct current bus by the storage battery unit and the fuel cell unit so as to supply power to the load.

Optionally, the uninterruptible power supply unit supplies power to the battery unit, the fuel cell unit, and the energy integrated management module according to the start signal, and includes:

the uninterruptible power supply unit supplies power to the fuel cell controller, the battery controller, and the DC controller.

Specifically, the fuel cell unit is provided in one-to-one correspondence with the first DC/DC converter unit, the battery unit is provided in one-to-one correspondence with the second DC/DC converter unit, and each converter unit includes a DC/DC converter and a DC controller. Each fuel cell unit includes a fuel cell and a fuel cell controller, and each battery unit includes a battery and a battery controller. And the energy comprehensive management module is connected with the fuel cell controller, the storage battery controller and the DC/DC controller in decibels. The uninterruptible power supply unit supplies power to the battery storage unit, the fuel cell unit and the energy comprehensive management module according to the starting signal, namely the uninterruptible power supply unit supplies power to the fuel cell controller, the battery controller and the DC/DC controller. And enabling the fuel cell controller, the storage battery controller and the DC/DC controller to complete self-checking and complete acquisition of state information of the fuel cell, the storage battery and the DC/DC converter.

Optionally, the uninterruptible power supply further includes, after the fuel cell controller, the battery controller and the DC/DC controller are powered on:

the energy comprehensive management module transmits a discharging instruction to the storage battery controller to control the storage battery to supply power to the direct current bus;

the direct current bus supplies power to the hydrogen supply unit so that the hydrogen supply unit completes self-inspection;

the energy comprehensive management module receives the self-checking information of the hydrogen supply module unit and judges whether the hydrogen supply unit meets the starting condition or not according to the self-checking information.

Specifically, after the battery controller of the battery unit is powered on and self-checked, the battery controller can control the battery to supply power to the dc bus according to the discharge instruction transmitted by the energy comprehensive management module, so that the dc bus has a certain amount of voltage. After the hydrogen supply unit obtains the voltage from the direct current bus, self-checking also needs to be completed. The hydrogen supply unit comprises a hydrogen system controller, and self-checking of the hydrogen supply unit is also completed through the hydrogen system controller. And meanwhile, whether the communication between the hydrogen system controller and the energy integrated management module is lost or not is checked, and corresponding information is transmitted to the energy integrated management module. The energy comprehensive management module receives the self-checking information of the hydrogen supply module unit and judges whether the hydrogen supply unit meets the starting condition or not according to the self-checking information.

Optionally, the starting method of the hybrid electric propulsion system further includes:

when the mode signal cannot be received, the energy comprehensive management module starts the hybrid electric propulsion system to enter a parking mode, a port entering and exiting mode, a navigation mode or a half-speed mode according to the speed signal;

when the mode signal and the speed signal are not received, the energy comprehensive management module starts the hybrid electric propulsion system according to the set starting rule.

Specifically, if no mode signal is input to the energy integrated management module, the power supply mode of the hybrid electric propulsion system of the ship can also be determined by receiving the navigation speed of the ship through the energy integrated management module. And when the comprehensive energy management module receives that the sailing speed of the ship is less than the first set speed, the output electric quantity of the power supply module is allocated in a parking mode. And when the comprehensive energy management module receives that the sailing speed of the ship is greater than the first speed and less than a second set speed, allocating the output electric quantity of the power supply module in an entering and exiting port or half-speed mode. And when the comprehensive energy management module receives that the navigation speed of the ship is greater than a second set speed, the output electric quantity of the power supply module is allocated in a navigation mode. The double-protection device provides double guarantee for meeting the power requirements of the running state and the fault mode of the ship, and further guarantees the electric quantity requirement of the ship in working. The stability of the power system is improved, the service characteristics and the service life of devices on the ship are ensured, and the effects of energy conservation and emission reduction are improved. In addition, the average navigational speed of the ship in the set time period monitored by the speed monitoring unit can be used as a speed signal, so that the accuracy of the speed signal can be improved, and the working mode which is inconsistent with the actual working state of the ship and triggered by the wrong speed signal can be prevented. And when the mode signal and the speed signal are not received, the energy comprehensive management module starts the hybrid electric propulsion system according to a set starting rule. For example, the energy integrated management module determines the starting output quantity and the output power of the fuel cell unit according to the SOC value of the storage battery unit.

An embodiment of the present invention further provides a method for controlling a marine storage battery unit, where a ship includes a plurality of storage battery units, each of the storage battery units is connected to the integrated energy management module, fig. 6 is a flowchart of a method for controlling a marine storage battery unit according to an embodiment of the present invention, and with reference to fig. 6, the method includes:

s210, the energy comprehensive management module sets a storage battery unit as a main control battery unit.

Specifically, the storage battery units of the whole ship are uniformly distributed on the left half string and the right half string to form a domain independently, and the batteries of the two domains are on line simultaneously under the normal condition and share the task of maintaining the voltage of the direct-current bus. The current of the battery cells should be balanced during the charging and discharging process of the battery cells, so that the SOC values of the batteries in the battery cells tend to be consistent. Therefore, the storage battery units on the ship can be uniformly charged and discharged, and the service lives of the storage battery units are close. The control mode of the storage battery unit is master-slave control. The main-slave control means that when the island operation mode is adopted, namely the storage battery units of the whole ship are divided into a domain by left and right half strings independently, wherein one storage battery unit power supply adopts constant voltage and constant frequency control (V/F control for short) and is used for providing voltage and frequency references for other storage battery units, and other distributed power supplies can adopt constant power control (P/Q control for short). The storage battery unit controlled by V/F is used as a main control battery unit. The power controller of the main control cell is referred to as a master controller, and the power controllers of the other secondary batteries are referred to as slave controllers.

And S220, the energy comprehensive management module receives the whole ship power request information and acquires the charge state information of each storage battery unit.

Specifically, after receiving the ship-wide power request information, the energy integrated management module acquires the state of charge information of the storage batteries in each storage battery unit through the storage battery controller of each storage battery unit, so that the state of charge information of the storage battery units of the whole ship is gathered in the energy integrated management module.

And S230, the main control battery unit distributes the power supply amount of each storage battery unit according to the state of charge information of each storage battery unit and the electricity request information of the whole ship.

Specifically, the battery controller of each battery unit is connected to the integrated energy management module, and therefore, the battery controller in the battery unit set as the main control battery unit can allocate the power supply amount of each battery unit according to the state of charge information of each battery unit and in combination with the ship-wide power request information. The overcharging or overdischarging of each storage battery unit on the ship is avoided, the service life of each storage battery unit is prolonged, and the stability and the safety of a power system are improved. Preferably, the power supply amount distributed to each storage battery unit is the same, so that the SOC values of the storage batteries in each storage battery unit tend to be consistent, thereby ensuring that the storage battery units on the ship are uniformly charged and discharged and have similar service lives.

And S240, controlling the power supply of the correspondingly connected storage battery units by the energy comprehensive management module according to the distributed power supply amount.

Specifically, the energy integrated management module determines the requested power of the corresponding storage battery unit according to the distributed power supply amount, and the storage battery unit outputs the corresponding output current according to the requested power.

The energy comprehensive management module judges whether a storage battery unit meets preset conditions of successful connection and discharge requirements of the storage battery unit, and if so, controls the storage battery unit to enter a main control mode; if not, then

And the energy comprehensive management module judges whether the next storage battery unit meets the preset condition or not until the setting of the main control battery unit is completed.

Specifically, each battery cell is equal in control before the main control cell is set. Each battery cell may be set as a main control cell. The energy comprehensive management module judges whether a storage battery unit meets a preset condition, and if so, controls the storage battery unit to enter a main control mode; if not, the energy comprehensive management module judges whether the next storage battery unit meets a first preset condition or not until the setting of the main control battery unit is completed. The preset conditions are whether the storage battery controller in the storage battery unit can perform information interaction with the energy comprehensive management module and whether the charge state of the storage battery in the storage battery unit meets the discharge requirement. Other condition requirements can also be included, and preset conditions can be set according to actual needs.

Optionally, the control method of the marine battery module further includes;

the energy comprehensive management module judges whether the main control battery unit meets the requirements of keeping connection with the energy comprehensive management module and whether the charge state of the storage battery unit meets the discharge requirements, and if so, the energy comprehensive management module maintains the main control mode; if not, exiting the main control mode.

After the main control mode is exited, the method further comprises the following steps:

and the energy comprehensive management module sets the next storage battery unit as a main control battery unit.

Specifically, after the energy integrated management module sets a storage battery unit as a main control battery unit, whether the main control battery unit meets preset conditions of keeping connection with the main control battery unit and whether the charge state of the storage battery unit meets a discharging requirement needs to be judged, and if the main control battery unit meets the preset conditions, a main control mode of the storage battery unit is maintained; if not, exiting the main control mode; and the energy comprehensive management module sets the next storage battery unit as a main control battery unit. The preset conditions may also be whether the battery controller in the battery unit can perform information interaction with the energy integrated management module, and whether the state of charge of the battery in the battery unit meets the discharge requirement. Other condition requirements can also be included and can be set according to actual needs.

Optionally, the control method of the marine battery module further includes: and when the setting of each storage battery unit as the main control battery unit fails, the energy comprehensive management module controls the power supply amount of each storage battery unit according to the droop control mode.

Specifically, when the setting of each battery unit to the main control battery unit fails, that is, when the master-slave control mode of the battery unit fails, the control mode of the battery unit enters the droop mode. And the energy comprehensive management module controls each storage battery unit according to a preset power supply amount distribution strategy. Optionally, the energy comprehensive management module may control the power supply amount of each battery unit according to the droop control mode, so as to evenly distribute the power supply amount of each battery unit. Therefore, the SOC values of the storage batteries in the storage battery units tend to be consistent, so that the storage battery units on the ship are ensured to be uniformly charged and discharged, and the service lives of the storage battery units are close.

Optionally, the battery controller limits charging and discharging of the storage battery according to the continuous charging and discharging multiplying factor and the maximum charging and discharging multiplying factor of each SOC value of the corresponding storage battery. The output current of the battery unit corresponding to the requested power output is determined based on the following equation:

IV_OC-I²R-P_request＝0；

voc is the open-circuit voltage of the storage battery unit in a charge state, and I is the output current; r is the equivalent internal resistance of the storage battery unit, R is the equivalent internal resistance of the storage battery, and the value changes along with the SOC. P_requestIs the requested power of the battery unit.

If the equation has a real root, controlling the output current to be:

if no solid root exists, controlling the output current to be:

the output voltage is then:

V＝V_OC-IR。

the instantaneous SOC value of the storage battery is as follows:

therein, SOC₀Is in an initial state of charge; q_maxIs the battery capacity. Considering only SOC vs. battery V_ocExemplary, lithium iron phosphate batteriesThe cell voltage curve can be seen in fig. 7.

Optionally, the control method of the marine storage battery module further includes that the energy comprehensive management module judges the state of charge of each storage battery, and triggers an alarm unit on the ship when the charge storage capacity of the storage battery unit is lower than 30%.

Specifically, in order to ensure that the battery unit has enough power to respond to the high-frequency power and enough electric energy to cope with the accident at any time, the SOC value of the battery in the battery unit needs to be effectively managed. The higher the SOC value is, the stronger the discharge capacity of the storage battery is; the lower the SOC value, the greater the allowable charging power to the battery. For example, the battery SOC value usage interval is 20% to 100%. In order to ensure a certain margin, the SOC value of the storage battery is designed to be within a range of 30% -80%, and when the SOC value is lower than 30%, an alarm unit on a ship is triggered. The battery stops supplying power and charges the battery. Further, overcharge or overdischarge of each storage battery unit on the ship is avoided, the service life of each storage battery unit is prolonged, and the stability and the safety of the power system are improved.

An embodiment of the present invention further provides a control method for a marine fuel cell unit, where a ship includes a plurality of fuel cell units, each fuel cell unit is connected to an energy integrated management module and is used for turning on, discharging, and turning off a fuel cell in the fuel cell unit, fig. 8 is a flowchart of the control method for the marine fuel cell unit according to the embodiment of the present invention, and with reference to fig. 8, the method includes:

and S310, determining the starting number of the fuel cell, and controlling to start the corresponding fuel cell according to the starting number of the fuel cell.

Specifically, the control of the fuel cell includes start-stop control and output power control. The start and stop are divided into normal start and stop and sudden stop, the normal start and stop and the power signal are realized by a communication mode, and the sudden stop is realized by hard wire connection. The power of the fuel cell is realized by controlling a DC/DC converter connected with the fuel cell by an energy comprehensive management module. The energy comprehensive management module determines the starting number of the fuel cell and controls to start the corresponding fuel cell according to the starting number of the fuel cell. For example, the power supply module of a ship includes 4 fuel cells in total, and the 4 fuel cells are numbered in advance. And the energy comprehensive management module determines that the two fuel cells need to be started with output power of 40KW according to the power requirement of the ship load, determines the numbers corresponding to the two fuel cells as the fuel cell starting numbers and controls to start the corresponding fuel cells according to the fuel cell starting numbers.

S320, determining the working state of the fuel cell, determining the target output power of the fuel cell according to the power requirement, and acquiring the actual output power of the fuel cell through a fuel cell controller; wherein the operating conditions include steady state and transient state.

Specifically, after the fuel cell is successfully started, the current needs to be slowly carried, and the current increase rate is provided by the fuel cell controller. The power supply of the fuel cell needs to maintain certain power output, and if the ship mode and the SOC value of the storage battery are both in a setting section, the power of the fuel cell is unchanged and the fuel cell works in a stable state; if the ship working mode or the SOC value of the storage battery changes, the power of the fuel cell needs to be changed, and the ship is considered to be in a transient state. The steady state means that the actual output power of the fuel cell is consistent with the target output power target (or close to the target output power within the allowable range), and the energy integrated management module maintains the power signal to the DC/DC controller to maintain the output power of the fuel cell unchanged by controlling the DC/DC converter connected with the fuel cell. The transient state is caused by a change in the ship operation mode or a change in the SOC value of the battery. The change of the working mode of the ship is determined by a mode signal input to the energy integrated management module by the mode selection unit or a speed signal input to the energy integrated management module by the speed monitoring unit, and the ship can enter a berthing mode, an entering and exiting port mode, a sailing mode and a half-speed mode after being started. The battery SOC value change is transmitted from the battery controller BMS to the integrated energy management module. And the energy comprehensive management module determines the starting number of the fuel cells and the output power provided by each fuel cell to the direct current bus according to the working mode of the ship and the state of charge of the storage battery on the ship. The energy comprehensive management module regulates the output power of the fuel cell through a DC/DC converter connected with the fuel cell.

S330, judging whether the difference value between the actual output power and the target output power is within a preset difference value range; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel battery is adjusted to the target output power by controlling a DC/DC converter connected with the fuel battery.

Alternatively, adjusting the output power of the fuel cell to the target output power by controlling the DC/DC converter connected thereto may include: the energy comprehensive management module determines the change rate of the output power of the fuel cell according to the target output power, the actual output power and the transient setting time, and transmits a power signal calculated correspondingly to a DC/DC controller of the DC/DC converter; the DC/DC controller controls the DC/DC converter to regulate the output power of the fuel cell according to the power signal.

Optionally, after the DC/DC controller controls the DC/DC converter to adjust the output power of the fuel cell according to the power signal, the method may further include: and the energy comprehensive management module receives the actual output power of the fuel cell fed back by the fuel cell controller, judges whether the actual output power of the fuel cell keeps up with the target output power within the transient set time, and increases the set transient time if the actual output power of the fuel cell does not keep up with the target output power.

Specifically, when the power of the fuel cell needs to be changed, the energy integrated management module determines the power change rate of the fuel cell according to the target output power, the actual output power and the transient setting time, and transmits a corresponding calculated power signal to the DC/DC controller to adjust the output power of the fuel cell. Meanwhile, the energy comprehensive management module also needs to receive a power signal of the fuel cell fed back by the fuel cell controller, determine whether the power of the fuel cell is close to the target output power according to the communication cycle, and increase the transient time until the set target value is reached if the power of the fuel cell is not close to the target output power. Optionally, the transient setting time is not more than 10 seconds, so as to ensure that the fuel cell can timely keep up with the demand of the direct current bus voltage when the ship normally works.

And S340, determining the fuel cell closing number, and controlling to close the corresponding fuel cell according to the fuel cell closing number.

Specifically, the energy integrated management module determines a fuel cell shutdown number corresponding to a fuel cell to be shut down according to the power demand of the ship load, and controls to shut down the corresponding fuel cell according to the fuel cell shutdown number.

The embodiment of the invention provides a control method of a marine power supply module, which is applied to the opening, the discharging and the closing of a storage battery in the power supply module, and the method comprises the following steps: determining a fuel cell opening number, and controlling to open the corresponding fuel cell according to the fuel cell opening number; and the energy comprehensive management module regulates the output power of the fuel cell through a DC/DC converter connected with the fuel cell according to the working mode of the ship and the charge state of the storage battery. And determining the fuel cell closing number, and controlling to close the corresponding fuel cell according to the fuel cell closing number. The power requirements of the ship in running states and fault modes are met, and the effects of energy conservation and emission reduction are achieved.

Alternatively, fig. 9 is a flowchart of the method shown in fig. 8 for each step in step S310, and referring to fig. 9, the controlling to turn on the corresponding fuel cell according to the fuel cell turn-on number includes:

s3110, the energy integrated management module transmits the fuel cell opening number to the hydrogen system controller.

And S3120, the hydrogen system controller controls to open the valve of the corresponding hydrogen cylinder group according to the opening number of the fuel cell.

S3130, the hydrogen system controller judges whether the valve of the corresponding hydrogen cylinder group is opened successfully; if the operation is unsuccessful, feeding back a hydrogen cylinder group opening failure signal to the energy comprehensive management module; the energy comprehensive management module transmits a next fuel cell starting number to the hydrogen system controller; if the hydrogen gas cylinder group is successfully opened, a hydrogen gas cylinder group opening success signal is fed back to the energy comprehensive management module.

S3140, after receiving the successful opening signal of the hydrogen cylinder group, the energy integrated management module sends an opening instruction signal to the corresponding fuel cell controller according to the opening number of the fuel cell.

S3150, the fuel cell controller judges whether the fuel cell is started successfully within the preset time; if the current is successful, controlling the fuel cell to output current; if the operation is unsuccessful, feeding back a fuel battery opening failure signal to the energy comprehensive management module; the integrated energy management module sends the start command signal to the fuel cell controller again.

S3160, the energy integrated management module judges whether the frequency of sending the starting instruction information is within the preset frequency, and if the frequency exceeds the preset frequency, the other fuel cell is controlled to be started.

Specifically, if the hybrid electric propulsion system includes 4 fuel cell units, two hydrogen cylinder groups are required. Each hydrogen cylinder group provides hydrogen gas to a pair of fuel cell units. And a manual switch is connected between the two hydrogen cylinder groups and used for controlling the communication state between the hydrogen cylinder groups. The problem that the power supply of the fuel cell is influenced because one hydrogen cylinder group cannot supply gas is solved, the stability of a power system is improved, and the service characteristics and the service life of devices on the ship are guaranteed. The hydrogen system controller is used for controlling the opening and closing of a bottleneck electromagnetic valve of the hydrogen cylinder group and is connected with the energy comprehensive management module. The energy comprehensive management module transmits the starting number of the fuel cell to the hydrogen system controller; and the hydrogen system controller controls to open the valve of the corresponding hydrogen cylinder group according to the opening number of the fuel cell. The hydrogen system control also needs to judge whether the hydrogen cylinder group is successfully opened or not, and if not, a hydrogen cylinder group opening failure signal is fed back to the energy comprehensive management module; and the energy integrated management module transmits the next fuel cell opening number to the hydrogen system controller. Or the next hydrogen cylinder group can be controlled to be opened, and the switch between the two hydrogen cylinder groups can be opened. The energy integrated management module sends an opening instruction signal to the corresponding fuel cell controller according to the fuel cell opening number, and can also feed back the failure of opening the hydrogen cylinder group for supplying hydrogen to the fuel cell to be opened to the energy integrated management module, so that the energy integrated management module can record and feed back information to workers. If the hydrogen cylinder group is successfully opened, feeding back a successful opening signal of the hydrogen cylinder group to the energy comprehensive management module; after the energy comprehensive management module receives the successful opening signal of the hydrogen cylinder group, the opening instruction signal can be directly sent to the corresponding fuel cell controller according to the opening number of the fuel cell.

Optionally, the fuel cell controller further determines whether the fuel cell is successfully started within a preset time; if the current is successful, controlling the fuel cell to output current so as to supply power to the direct current bus; if the fuel cell is not successful, a fuel cell opening failure signal is fed back to the energy comprehensive management module, and the energy comprehensive management module sends an opening instruction signal to the fuel cell controller again. And the energy comprehensive management module judges whether the frequency of sending the starting instruction information is within a preset frequency, and controls to start another fuel cell if the frequency exceeds the preset frequency.

Exemplarily, fig. 10 is another flowchart of the method flowchart shown in fig. 8 for each step in step S310, and referring to fig. 10, the method includes:

s3170, determining the fuel cell opening number.

And S3180, sending the information to a hydrogen system controller, and opening a corresponding valve.

S3190, judging whether the opening is successful. If the result is successful, step S31110 is executed, and if the result is unsuccessful, the process returns to step S3170.

S31110, recording the opening times S.

S31120, sending a fuel cell opening signal.

S31130, judging whether the starting is successful. If the result is successful, step S31140 is executed, and if the result is unsuccessful, step S31150 is executed.

S31140, allowing the load current.

And S31150, adding 1 to the opening times, wherein S is S + 1.

S31160, judging whether the opening times is more than 3, and S is more than 3. If so, step S31170 is executed, and if not, the process returns to step S31120.

And S31170, starting another fuel cell.

Alternatively, fig. 11 is a schematic flow chart of each step in the flow chart of the method shown in fig. 8 for step S330, referring to fig. 11, determining a fuel cell shutdown number, and controlling to shut down the corresponding fuel cell according to the fuel cell shutdown number, including:

and S3310, controlling to close the fuel cell by the energy comprehensive management module through the fuel cell controller according to the fuel cell closing number, and controlling the DC/DC converters connected with the fuel cells in a one-to-one correspondence manner to reduce the output power to zero.

S3320, the fuel cell controller feeds back the shutdown signal to the energy comprehensive management module.

S3330, the energy integrated management module transmits a valve closing signal to the hydrogen system controller according to the shutdown signal to control to close the hydrogen cylinder group supplying hydrogen to the fuel cell.

And S3340, stopping the action of the proportional control valve arranged on the pipeline between the fuel cell and the hydrogen cylinder group.

Specifically, during normal shutdown, the fuel cell needs a certain time to unload, and the DC/DC converter needs to be controlled to cooperate. After the output power of the fuel cell is reduced to 0 by controlling the DC/DC converter, residual reaction gas in the fuel cell needs to be removed, the air side is controlled by the fuel cell controller, and the hydrogen side is controlled by the hydrogen system controller. The energy comprehensive management module transmits a valve closing signal to the hydrogen system controller according to the shutdown signal so as to control to close the hydrogen cylinder group supplying hydrogen for the fuel cell and stop the action of a proportional regulating valve arranged on a pipeline between the fuel cell and the hydrogen cylinder group.

Fig. 12 is a flowchart of another control method for a fuel cell unit for a ship, according to an embodiment of the present invention, which is applied to power supply control for the fuel cell unit in different operation modes of the ship, and referring to fig. 12, the method includes:

s410, the energy comprehensive management module triggers mode control or non-mode control according to the mode selection signal and the speed signal; wherein the ship operation mode includes at least one of a berthing mode, an entering and exiting mode, a sailing mode, or a half-speed mode under the mode control.

Specifically, the control of the output power of the fuel cell unit includes non-mode control and mode control. The control of the fuel cell unit by the integrated energy management module requires first determining whether the control of the fuel cell unit is the non-mode control or the mode control. And the energy comprehensive management module triggers mode control or non-mode control according to the mode selection signal and the speed signal. Wherein the ship operation mode includes at least one of a berthing mode, an entering and exiting mode, a sailing mode, or a half-speed mode under the mode control. The energy comprehensive management module is connected with the mode selection unit and can determine the ship working mode according to the mode signal input by the mode selection unit. The integrated energy management module is also connected with the speed monitoring unit and determines a parking mode, an entering and exiting port mode, a sailing mode and a half-speed mode of the hybrid electric propulsion system according to the speed signal input by the speed monitoring unit.

Optionally, the triggering of the mode control or the non-mode control by the energy comprehensive management module according to the mode selection signal and the speed signal includes: judging whether a mode signal is input; if a mode signal is input, triggering mode control; if no mode signal is input, judging whether a speed signal is input; if a speed signal is input, triggering mode control; if no speed signal is input, triggering non-mode control; the energy comprehensive management module controls the energy output of the fuel cell unit according to the mode signal or the speed signal, so that the stability of the power system is improved, the service characteristics and the service life of devices on the ship are ensured, and the effects of energy conservation and emission reduction are improved.

And S420, controlling the starting number of the fuel cells in the fuel cell unit and the output power of the fuel cells according to the state of charge of the storage battery unit when the energy comprehensive management module is in non-mode control.

Specifically, the ship comprises a plurality of fuel cell units and a plurality of storage battery units. Each fuel cell unit includes a fuel cell and a fuel cell controller provided in association with each fuel cell. Each battery unit includes a battery and a battery controller provided in a pair with each battery. The energy integrated management module controls the opening of the corresponding battery and calculates the change rate of the output current of the battery through each battery controller. Each battery is also correspondingly connected with a DC/DC converter, and the energy comprehensive management module can also control the output power of the corresponding battery to supply power to the direct current bus through the DC/DC converter. And the energy comprehensive management module acquires the charge state according to the storage battery unit during non-mode control, and controls the starting number of the fuel cells in the fuel cell unit and the output power of the fuel cells according to the charge state of the storage battery unit.

Optionally, when the fuel cell unit is in the non-mode control, the output power and the starting number of the fuel cell unit are controlled according to the state of charge of the battery unit, including:

acquiring the state of charge of the storage battery unit;

if the state of charge of the storage battery unit is smaller than a first set state of charge threshold value, controlling all fuel cells in the fuel cell unit to be started at output power larger than the first set power threshold value; and adjusting the output power of the fuel cell according to the state of charge of the battery cell;

and if the state of charge of the storage battery unit is larger than a second set charge threshold, controlling the fuel cells in the fuel cell unit to output constantly at a first set power threshold, and determining the starting number of the fuel cells according to the state of charge of the storage battery unit.

Specifically, the energy comprehensive management module acquires the state of charge of the storage battery unit through the storage battery controller. The minimum value among SOC values corresponding to a plurality of storage batteries may be used as the determination value. Preferably, the SOC values of the storage batteries in the storage battery units are kept to be consistent, so that the storage battery units on the ship are ensured to be uniformly charged and discharged, and the service lives of the storage battery units are close to each other. If the state of charge of the storage battery unit is smaller than a first set state of charge threshold value, triggering a power mode, and controlling the fuel cell in the fuel cell unit to be started in a whole way at the output power larger than the first set power threshold value; and if the state of charge of the storage battery unit is larger than a second set charge threshold, triggering an economy mode, controlling the fuel cell in the fuel cell unit to output constantly at a first set power threshold, and determining the starting number of the fuel cell according to the state of charge of the storage battery unit. Fig. 13 is a control strategy diagram of a marine fuel cell unit under non-mode control according to an embodiment of the present invention, and referring to fig. 13, for example, the SOC value limit points of the battery cells of the two modes are 55% and 60%. When the SOC value of the storage battery unit is reduced to be below 55%, a power mode is triggered; when the SOC of the battery unit rises to 60% under the SOC value, the economic mode is triggered. In the economic mode, the output power of the fuel cell is 40 kW; and in the power mode, the fuel cell is completely started, and the output power is more than 40 kW.

Optionally, adjusting the output power of the fuel cell according to the state of charge of the battery unit includes:

determining an increase amount of the output power of each fuel cell according to a first set decrease amount of the state of charge of the battery unit if the state of charge of the battery unit is in a decreasing process;

and if the state of charge of the battery module is in the rising process, determining the reduction amount of the output power of each fuel cell according to the second set increase amount of the state of charge of the battery unit.

Specifically, the power mode is triggered, indicating that the SOC value of the battery in the battery unit is relatively low. For example, when the SOC of the battery is less than 55% or the SOC is still less than 60% during the charge ramp-up, the ability to maintain a heavy load is reduced, and the output power of the fuel cell needs to be increased to ramp-up the SOC of the battery. Fig. 14 is a schematic view of the turn-on level of a marine fuel cell unit under non-mode control according to an embodiment of the present invention, and referring to fig. 14, the output power of the fuel cell is different according to the SOC value of the battery, and the power mode is classified such that the lower the SOC value, the higher the grade, the higher the output power, and the further decrease in the SOC value of the battery is prevented. The method is divided into four stages temporarily: level 1, the output power of the fuel cell is 60 kW; 2, the output power of the fuel cell is 80 kW; grade 3, the output power of the fuel cell is 100 kW; class 4, fuel cell output power 110 kW. In the process of reducing the SOC value of the storage battery, the trigger values are 55%, 49%, 43% and 37%, and are respectively 1 level, 2 level, 3 level and 4 level; during the raising of the SOC value of the battery, the trigger values are 42%, 48%, 54%, and 60%, which are respectively level 3, level 2, level 1, and economy mode.

Alternatively, determining the number of starts of the fuel cell according to the state of charge of the battery cell includes:

determining an increased number of starts of the fuel cell based on a third set reduction in the state of charge of the battery unit if the state of charge of the battery unit is in the process of decreasing;

and if the state of charge of the battery unit is in the process of rising, determining the starting number of the fuel cell reduction according to the fourth set increment of the state of charge of the battery unit.

Specifically, the economy mode is triggered, indicating that the SOC value of the battery in the battery cell is relatively high. For example, the number of fuel cells is 4, in the economy mode, the output power of the fuel cells is a constant value of 40kW, and the opening number is still determined by the SOC value of the storage battery and is opened and closed in a stepped manner. Fig. 15 is a schematic diagram of the number of fuel cells for a ship according to an embodiment of the present invention that are turned on under non-mode control, and referring to fig. 15, in the process of decreasing the SOC value of the battery, the trigger values are 0.77%, 74%, 71%, and 68%, and 1, 2, 3, and 4 fuel cells are turned on respectively; during the rise of the SOC value of the battery, the trigger values were 7%, 73%, 76%, and 79%, and 3, 2, 1, and 0 were turned on.

And S430, controlling the starting number of the fuel cells in the fuel cell unit and the output power of the fuel cells by the energy comprehensive management module according to the ship working mode corresponding to the mode selection signal or the ship working mode corresponding to the speed signal during mode control.

Specifically, under the mode control, the ship working mode comprises at least one of a berthing mode, an entering and exiting port mode, a sailing mode or a half-speed mode. And the energy comprehensive management module determines the working mode of the ship according to the mode signal or the speed signal, so that the output power of the fuel cell and the starting number of the fuel cell are correspondingly controlled. The energy comprehensive management module controls the energy output of the fuel cell unit according to the mode signal or the speed signal, so that the stability of the power system is improved, the service characteristics and the service life of devices on the ship are ensured, and the effects of energy conservation and emission reduction are improved.

Optionally, after entering the parking mode, controlling the output power of the fuel cells in the battery unit and the number of started fuel cells according to the input mode includes:

and if the state of charge of the storage battery is smaller than a third set state of charge threshold value, controlling to start two fuel cells with lower power generation amount on two sides, and controlling the output power of the fuel cell with lower power generation amount to be a first preset power threshold value.

If the state of charge of the storage battery is larger than a third set state of charge threshold and smaller than a fourth set state of charge threshold, controlling to start a fuel cell and controlling the output power of the fuel cell to be a first preset power threshold;

and if the charge state of the storage battery is larger than the fourth set charge state threshold value, the fuel cell is not started.

Exemplarily, fig. 16 is a flowchart of a control method of a fuel cell unit for a ship under mode control according to an embodiment of the present invention, and referring to fig. 16, after a ship enters a berthing mode, without accessing shore power, when a load exists on the ship, a part of fuel cells are required to be turned on and operate at an output power of 40 kW. If the SOC value of the battery is greater than 80%, the power can be supplied from the battery without starting the fuel cell (step a in fig. 16). If the SOC value of the battery is less than 40%, the load on the ship after the ship enters the berthing mode is a low power demand device such as daily lighting, and therefore the fuel cell controlled to be turned on is a fuel cell with a low power generation amount on both sides of the fuel cell (step B in fig. 16). When the SOC of the storage battery rises back to more than 50%, one storage battery is closed. Optionally, before controlling to start up one fuel cell, the method further includes: judging the hydrogen pressure and the preset pressure threshold value in the hydrogen cylinder group supplied with hydrogen by the fuel cell with lower power generation capacity on one side; if the pressure of hydrogen in the hydrogen cylinder group is greater than a preset pressure difference threshold value, controlling to start the fuel cell with the reduced power generation amount on the side (step C in the figure 16); if the pressure of hydrogen in the hydrogen cylinder group is less than the preset pressure difference threshold, the fuel cell with low power generation on the side with high starting pressure is controlled (step D in fig. 16). For example, the preset pressure difference threshold may be 2Mpa, so as to ensure that the hydrogen cylinder group can normally supply hydrogen to the fuel cell, thereby ensuring that the fuel cell supplies power to the ship and improving the stability of the ship power system.

Optionally, after entering the port entry and exit mode, controlling the output power of the fuel cells in the battery module and the starting number of the fuel cells according to the input mode, including:

controlling each fuel cell to be started; if the state of charge of the storage battery is larger than a fifth set state of charge threshold value, controlling the output power of each fuel cell to be a first preset power threshold value;

if the state of charge of the storage battery is smaller than a fifth set state of charge threshold and larger than a sixth set state of charge threshold, controlling the output power of each fuel cell to be a second preset power threshold;

if the state of charge of the storage battery is smaller than a sixth set state of charge threshold value, controlling the output power of each fuel cell to be a third preset power threshold value; the first preset power threshold is smaller than the second preset power threshold, and the second preset power threshold is smaller than the third preset power threshold.

Illustratively, the ship is provided with 4 fuel cells, and when the ship enters the port entering and exiting mode, the 4 fuel cells are all started. When the SOC value of the storage battery is larger than 50%, the energy comprehensive management module controls the output power of each fuel battery to be 40kW (step E in FIG. 16); when the SOC value of the storage battery is smaller than or equal to 50% and larger than 40%, the energy comprehensive management module controls the output power of each fuel cell to be 60kW (step F in FIG 16); when the SOC value of the battery is less than or equal to 40%, the integrated energy management module controls the output power of each fuel cell to 80kW (step G in fig. 16). And increasing the power supply of the fuel cell, and simultaneously charging each storage battery until the SOC value of the storage battery reaches 55%, and controlling the output power of the fuel cell to be reduced back to 40 kW.

Optionally, after entering the sailing mode, controlling the output power of the fuel cells in the battery module and the starting number of the fuel cells according to the input mode, including:

controlling each fuel cell to be started; if the state of charge of the storage battery is larger than a seventh set state of charge threshold value, controlling the output power of each fuel cell to be a fourth preset power threshold value;

if the state of charge of the storage battery is smaller than a seventh set state of charge threshold and larger than an eighth set state of charge threshold, controlling the output power of each fuel cell to be a fifth preset power threshold;

if the state of charge of the storage battery is smaller than the eighth set state of charge threshold and larger than the ninth set state of charge threshold, controlling the output power of each fuel cell to be a sixth preset power threshold;

if the state of charge of the storage battery is smaller than a ninth set state of charge threshold value, controlling the output power of each fuel cell to be a seventh preset power threshold value;

the fourth preset power threshold is smaller than a fifth preset power threshold, and the fifth preset power threshold is smaller than a sixth preset power threshold; the sixth preset power threshold is smaller than the seventh preset power threshold.

Illustratively, the ship is provided with 4 fuel cells, and when the ship enters a sailing mode, the 4 fuel cells are all started. Once the SOC value of the storage battery is reduced, the power of the fuel cell is increased step by step to ensure that the SOC of the storage battery is not less than 55 percent and the maximum output power of the fuel cell is 200 kW. When the SOC value of the storage battery is larger than 68%, the energy comprehensive management module controls the output power of each fuel cell to be 50kW (step H in FIG 16); when the SOC value of the storage battery is less than or equal to 68% and greater than 64%, the energy integrated management module controls the output power of each fuel cell to be 70kW (step I in FIG 16); when the SOC value of the battery is less than or equal to 64% and greater than 60%, the integrated energy management module controls the output power of each fuel cell to be 90kW (step J in fig. 16); when the SOC value of the battery is less than or equal to 60%, the integrated energy management module controls the output power of each fuel cell to 110kW (step K in fig. 16).

Alternatively, the half-speed mode is determined based on the integrity of the fuel cell unit and/or the battery unit; wherein the number of the storage battery units is two; the number of the fuel cell units is at least two;

if the number of the storage battery units in normal operation is less than two and/or the number of the fuel battery units in normal operation is less than two; the power demand on the battery module and the fuel cell is reduced by reducing the boat speed.

Specifically, when the fuel cell in the fuel cell unit or the storage battery in the storage battery unit is damaged, the control mode of the fuel cell and the control mode of the storage battery need to be changed, and when the change mode can not meet the load requirement, the power shortage is reminded, and the load reduction operation is carried out. An average power of about 185kW for a voyage indicates that at least 2 fuel cells are required to meet full power operation. The storage battery plays a role in stabilizing bus voltage and providing power of transient load, when 1 storage battery is lost, available power is reduced by half, the maximum power of the fuel cell is also limited, and the ship needs to sail at half speed under the condition. Illustratively, if the number of the storage batteries of the ship is 2, the number of the fuel cells is 4. According to the number of lost combinations of fuel cells and batteries, the following can be classified: "3 fuel cell +2 battery", "2 fuel cell +2 battery", "1 fuel cell +2 battery", "0 fuel cell +2 battery", "4 fuel cell +1 battery", "3 fuel cell +1 battery", "2 fuel cell +1 battery", "1 fuel cell +1 battery", "0 fuel cell +1 battery", and only fuel cell.

There are many combinations of fuel cells and batteries, and an optimal control method is not realized for each combination. The above combinations need to be classified, and combinations that can satisfy the full power operation of the ship are reserved. The other combinations all adopt a speed reduction mode to reduce power, but the control mode of the power source is unchanged, and the load on the ship is changed. When only the fuel cell is operating, it is also desirable to further limit the rate of change of the load. In the above combination, theoretically, only two combinations of "3 fuel cell +2 battery" and "2 fuel cell +2 battery" can ensure both power and endurance, and can operate at full power.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions without departing from the scope of the invention. Therefore, although the present invention has been described in more detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for controlling a fuel cell unit for a ship, the ship comprising a plurality of fuel cell units, each fuel cell unit being connected to an integrated energy management module for controlling the power supply of fuel cells in the fuel cell units, the method comprising:

determining the working state of the fuel cell, determining the target output power of the fuel cell according to the power demand, and acquiring the actual output power of the fuel cell through a fuel cell controller; wherein the operating conditions include steady state and transient state;

judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the fuel cell;

and determining the closing number of the fuel cell, and controlling to close the corresponding fuel cell according to the closing number of the fuel cell.

2. The method of controlling a marine fuel cell unit according to claim 1, wherein the power supply module further includes a hydrogen supply unit including a hydrogen system controller and a plurality of hydrogen cylinder groups; the fuel cell controller of each fuel cell and the hydrogen system controller are connected with a comprehensive energy management unit;

the hydrogen system controller judges whether the valve of the corresponding hydrogen cylinder group is opened successfully; if the operation is unsuccessful, feeding back a hydrogen cylinder group opening failure signal to the comprehensive energy management unit; the integrated energy management unit transmits a next fuel cell start number to the hydrogen system controller; if successful, then

3. The method for controlling a marine fuel cell unit according to claim 2, wherein the step of transmitting an on command signal to the corresponding fuel cell controller in accordance with the fuel cell on number further includes:

4. The method for controlling a marine fuel cell unit according to claim 3, wherein the integrated energy management unit further includes, after sending the start command signal to the fuel cell controller again:

5. The method for controlling a marine fuel cell unit according to claim 1, wherein the adjusting the output power of the fuel cell to the target output power by controlling a DC/DC converter connected thereto includes:

6. The method for controlling a marine fuel cell unit according to claim 5, wherein the DC/DC controller controls the DC/DC converter to adjust the output power of the fuel cell according to the power signal, and further comprises:

7. The method according to claim 6, wherein the transient setting time is not more than 10 seconds.

8. The method for controlling a marine fuel cell unit according to claim 2, wherein the determining a fuel cell shutdown number and controlling the shutdown of the corresponding fuel cell according to the fuel cell shutdown number includes:

the comprehensive energy management unit controls the fuel cell to be closed through a fuel cell controller according to the fuel cell closing number, and controls the DC/DC converters connected with the fuel cells in a one-to-one correspondence mode to reduce the output power to zero;

and the comprehensive energy management unit transmits a valve closing signal to the hydrogen system controller according to the shutdown signal so as to control to close the hydrogen cylinder group supplying hydrogen to the fuel cell.

9. The method of claim 8, wherein the fuel cell controller further comprises, after feeding back the shutdown signal to the integrated energy management unit:

10. A hybrid electric propulsion system is characterized by comprising an energy comprehensive management module and a plurality of fuel cell units, wherein each fuel cell unit is connected with the energy comprehensive management module, and the energy comprehensive management module is used for controlling fuel cells in the fuel cell units, and comprises a control module for determining the opening number of the fuel cell and controlling the opening of the corresponding fuel cell according to the opening number of the fuel cell; the fuel cell controller is also used for determining the target output power of the fuel cell in real time according to the power requirement and acquiring the actual output power of the fuel cell through the fuel cell controller; judging whether the difference value between the actual output power and the target output power is within a preset difference value range or not; if the difference value is within the preset difference value range, the output power of the fuel cell is maintained by controlling a DC/DC converter connected with the difference value; if the difference is not within the preset difference range, the output power of the fuel cell is adjusted to the target output power by controlling a DC/DC converter connected with the fuel cell; and the controller is used for determining the fuel cell closing number and controlling to close the corresponding fuel cell according to the fuel cell closing number.