Green hydrogen production, storage and transportation integrated ship system for offshore wind power and its operation method

Abstract

The present invention provides an integrated ship system for the production, storage and transportation of green hydrogen for offshore wind power and its operation method, which relates to the technical field of offshore wind power development. The system includes a ship and a hydrogen production device and a hydrogen storage device arranged in the ship. The hydrogen production device is used to electrolyze seawater or fresh water into hydrogen and oxygen. The hydrogen storage device is used to store the hydrogen produced by the hydrogen production device. The ship is used to connect to an offshore wind power base station and travel between the offshore wind power base station and the home port. The present invention integrates the hydrogen production and storage devices inside the ship, and at the same time realizes the integrated production, storage and transportation of offshore green hydrogen. It has a simple structure and clear functions. It can be precisely customized according to the scale of offshore wind power, reducing the construction volume and cost, reducing the maintenance difficulty of each equipment, and improving the stability and flexibility of the entire system. It can also be manufactured, modified, maintained and repaired on shore, avoiding high-cost and high-risk offshore and seabed operations.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power development, and in particular to a green hydrogen production, storage and transportation integrated ship system for offshore wind power and an operation method thereof. Background Art

[0002] The total installed capacity of offshore wind power in the world has reached 57GW, of which my country's total installed capacity of offshore wind power accounts for nearly half (26.4GW), and has a development potential of 3,500GW. Faced with the two major difficulties of offshore wind power grid connection and high transmission costs, the energy storage method of green hydrogen production will greatly promote the efficient use of offshore wind power.

[0003] At present, there are two main modes for producing green hydrogen through offshore wind power. One is the onshore hydrogen production mode, which transmits the electricity generated by the offshore wind farm to the land through submarine power cables for hydrogen production on land. This mode is only applicable to offshore wind farms. For offshore and deep-sea wind farms, there is also an offshore hydrogen production mode. This mode requires the construction of a green hydrogen production platform at sea, the transmission of electricity from the offshore wind farm to the hydrogen production platform, the installation of a green hydrogen storage device on the seabed, and the transportation of green hydrogen by ship. However, this decentralized system leads to high construction and maintenance costs, and involves complex and dangerous offshore and submarine operations, which increases the risk-return ratio of the entire system. There is also an existing technology that integrates offshore wind power, hydrogen production, and hydrogen storage on an offshore fixed platform or an offshore movable platform, but this method has a high construction cost and low system flexibility. Summary of the invention

[0004] The problem to be solved by the present invention is that the existing offshore wind power production of green hydrogen integrates offshore wind power and hydrogen production, hydrogen storage, etc. on the offshore platform, which has the problems of high construction cost and low system flexibility.

[0005] In order to solve at least one aspect of the above problems, the present invention provides an integrated green hydrogen production, storage and transportation ship system for offshore wind power, including: a ship and a hydrogen production device and a hydrogen storage device arranged in the ship, the hydrogen production device is used to electrolyze seawater or fresh water into hydrogen and oxygen, the hydrogen storage device is used to store the hydrogen produced by the hydrogen production device, and the ship is used to connect to an offshore wind power base station and travel between the offshore wind power base station and the home port.

[0006] Preferably, the hydrogen production device comprises an electrolytic cell, and the electrolytic cell is connected to the hydrogen storage device via a first hydrogen transmission pipeline.

[0007] Preferably, the hydrogen storage device comprises a dryer, a compressor and a hydrogen storage tank connected in sequence, the dryer is used to remove moisture from the hydrogen produced by the hydrogen production device, the compressor is used to compress the dried hydrogen, and the hydrogen storage tank is used to store compressed hydrogen.

[0008] Preferably, the integrated green hydrogen production, storage and transportation ship system for offshore wind power also includes a seawater desalination device, which includes a seawater desalination tank and a filter, a sterilizer, a reverse osmosis device and an electrodialysis device arranged in the seawater desalination tank and connected in sequence. The seawater desalination tank is provided with a water inlet, and the seawater desalination tank draws seawater through the water inlet, and the seawater enters the filter, the sterilizer, the reverse osmosis device and the electrodialysis device in sequence for desalination treatment.

[0009] Preferably, the integrated green hydrogen production, storage and transportation ship system for offshore wind power also includes a fresh water storage tank, a first heat exchanger and a second heat exchanger; one end of the fresh water storage tank is connected to the electrodialysis device, and the other end of the fresh water storage tank is connected to the electrolytic cell; one end of the first heat exchanger is connected to the engine of the ship, and the other end of the first heat exchanger is connected to the fresh water storage tank; one end of the second heat exchanger is connected to the engine of the ship, and the other end of the second heat exchanger is connected to the electrolytic cell.

[0010] Preferably, the integrated green hydrogen production, storage and transportation ship system for offshore wind power also includes a power electronic conversion device, the offshore wind power base station includes a wind turbine set, the wind turbine set is used to generate electricity through wind power, and the power electronic conversion device is used to convert the electric energy generated by the wind turbine set into electric energy of the specifications required by the hydrogen production device and the seawater desalination device.

[0011] Preferably, the power electronic conversion device comprises:

[0012] An AC / DC converter, used to convert the alternating current generated by the wind turbine into direct current in a DC bus;

[0013] A DC / AC converter, connected to the DC bus and the seawater desalination device, respectively, for converting the DC power in the DC bus into AC power of the specification required by the seawater desalination device;

[0014] A first DC / DC converter, connected to the DC bus and the electrolytic cell respectively, for converting the DC power in the DC bus into DC power of the specification required by the electrolytic cell;

[0015] The second DC / DC converter is connected to the DC bus and the battery respectively, and is used to convert the DC power in the DC bus and store it in the battery. The battery is used to provide living electricity for the ship and to be used for peak shaving and valley filling of the electrolytic cell.

[0016] The advantages of the green hydrogen production, storage and transportation integrated ship system for offshore wind power of the present invention compared with the prior art are:

[0017] The present invention integrates the hydrogen production and storage devices inside the ship, and realizes the integrated production, storage and transportation of offshore green hydrogen. It has a simple structure, modular setting, clear functions, and can be precisely customized according to the scale of offshore wind power. It reduces the construction workload and cost of traditional offshore wind power hydrogen production equipment, reduces the maintenance difficulty of each equipment, improves the stability and flexibility of the entire system, and can be manufactured, modified, maintained and repaired on shore, avoiding high-cost and high-risk offshore and seabed operations.

[0018] The present invention also provides an operation method of a green hydrogen production, storage and transportation integrated ship system for offshore wind power, comprising:

[0019] Step S1, a first ship carrying an empty hydrogen storage tank departs from a home port and arrives at a designated offshore wind power base station, anchors the hull of the first ship, and connects the first ship to the offshore wind power base station;

[0020] Step S2, extracting seawater for desalination through the seawater desalination device in the first ship, and storing a certain amount of pure water in a fresh water storage tank in the first ship;

[0021] Step S3, electrolyzing pure water through the electrolytic cell in the first ship, and storing hydrogen obtained by the electrolysis in a hydrogen storage tank of the first ship;

[0022] Step S4, when the hydrogen storage tank of the first ship reaches the set storage capacity, a second ship carrying an empty hydrogen storage tank departs from the home port, and when the second ship arrives at the offshore wind power base station, the hydrogen storage tank of the first ship is fully filled with hydrogen;

[0023] Step S5, interrupting the power connection between the first ship and the offshore wind power base station, and returning the first ship to the home port, while the second ship anchors the hull and connects to the offshore wind power base station, repeating the work of the first ship.

[0024] Preferably, the number of the first ships and the number of the second ships are respectively plural, and the number of power interfaces of the offshore wind power base station is greater than or equal to the larger number of the first ships and the second ships.

[0025] Preferably, the connection between the first ship and the second ship and the offshore wind power base station includes: power connection and communication connection between the first ship and the second ship and the offshore wind power base station, wherein the communication connection between the first ship and the second ship and the offshore wind power base station is based on a handshake communication protocol.

[0026] The advantages of the operation method of the green hydrogen production, storage and transportation integrated ship system for offshore wind power of the present invention compared with the existing technology are the same as the advantages of the green hydrogen production, storage and transportation integrated ship system for offshore wind power compared with the existing technology, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural block diagram of a green hydrogen production, storage and transportation integrated ship system for offshore wind power in an embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of the deployment of various modules of the green hydrogen production, storage and transportation integrated ship system for offshore wind power in an embodiment of the present invention;

[0029] Figure 3 It is a schematic diagram of the overall structure of an integrated green hydrogen production, storage and transportation ship system for offshore wind power in an embodiment of the present invention.

[0030] Description of reference numerals:

[0031] 1- desalination tank; 101- water inlet; 102- water pump; 103- filter; 104- sterilizer; 105- reverse osmosis device; 106- electrodialysis device; 2- fresh water storage tank; 3- battery; 4- AC / DC converter; 5- electrolytic cell; 6- pH control device; 7- dryer; 8- compressor; 9- hydrogen storage tank; 901- first high-pressure hydrogen storage tank; 902- first high-pressure hydrogen storage tank; 10- first heat exchanger; 11- The second heat exchanger; 12-power interface; 13-onshore hydrogen side; 14-cockpit; 15-chimney; 16-steering cabin; 17-propeller; 18-engine; 19-first bottom hold; 20-first cabin; 21-second bottom hold; 22-second cabin; 23-bulb bow; 24-first hydrogen pipeline; 25-second hydrogen pipeline; 26-first lightning protection device; 27-second lightning protection device; 28-first window; 29-second window. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0033] An embodiment of the present invention provides an integrated green hydrogen production, storage and transportation ship system for offshore wind power (hereinafter referred to as a green hydrogen ship system), comprising: a ship and a hydrogen production device and a hydrogen storage device arranged in the ship, the hydrogen production device is used to electrolyze seawater or fresh water into hydrogen and oxygen, the hydrogen storage device is used to store the hydrogen produced by the hydrogen production device, and the ship is used to connect to an offshore wind power base station and travel between the offshore wind power base station and the home port.

[0034] The green hydrogen ship system of this embodiment, by cooperating with the offshore wind power base station, can realize the production and storage of green hydrogen on the ship at the same time, and directly transport it by ship after the green hydrogen is fully stored, realizing the integration of green hydrogen preparation, storage and transportation, reducing the construction volume and cost of traditional offshore wind power hydrogen production equipment, reducing the maintenance difficulty of each equipment, and improving the stability and flexibility of the entire system. After the ship receives the power supply from the offshore wind power base station, the hydrogen production device can stably output hydrogen and store it in the hydrogen storage device. When the ship is fully loaded with hydrogen, it can be disconnected from the offshore wind power base station or transferred with the subsequent empty ship. The ship full of hydrogen returns to the home port and transports the green hydrogen to land for use, thereby continuously obtaining green hydrogen fuel from offshore wind power, which is of great significance to the coastal areas rich in offshore wind energy, especially the efficient utilization of deep sea wind energy. It should be noted that the hydrogen production device of this embodiment can directly electrolyze seawater to produce hydrogen, or it can electrolyze fresh water, wherein the fresh water can be transported from the shore to the wind farm, or it can be obtained by desalination. Desalination by seawater desalination will be described in detail later.

[0035] In some of the embodiments, the hydrogen production device includes an electrolytic cell 5 , and the electrolytic cell 5 is connected to the hydrogen storage device via a first hydrogen transmission pipeline 24 .

[0036] The electrolytic cell 5 is a water electrolysis hydrogen production technology. It only needs to supply pure water and electricity to it to continuously produce hydrogen and oxygen, and its energy efficiency can reach 80%, such as proton exchange membrane electrolytic cell, alkaline electrolytic cell, solid oxide electrolytic cell, etc. Compared with other hydrogen production technologies, the electrolytic cell has the advantages of high rate, high purity, and fast response. It is a very promising green hydrogen production technology when matched with wind power generation technology. The electrolytic cell can be used to store wind power obtained from the deep sea in hydrogen fuel by electrolyzing water, and transported back to land for wide use in power generation, chemical industry, transportation, aerospace and other fields. At present, most commercial-grade electrolytic cell products are developed for land-based applications and cannot adapt to the high-salt and high-corrosion environment at sea for a long time. To address this problem, the electrolytic cell 5 in this embodiment has its metal components spray-coated for protection, especially the metal parts at the hydrogen end, to ensure production safety.

[0037] In some of the embodiments, the green hydrogen ship system also includes a battery 3. The battery is an electrochemical energy storage device with the advantages of fast response, stability and reliability, and efficient storage. Its main function is to stabilize the power input of the electrolytic cell and avoid safety accidents such as electrical breakdown or hydrogen breakdown of the electrolytic cell due to transient large current. Commercial-grade batteries such as lithium batteries and lead-acid batteries can be used according to the rated power of the electrolytic cell. Specifically, when wind power exceeds the working demand of the electrolytic cell 5, the extra power is temporarily stored; when wind power is insufficient to supply the electrolytic cell 5, the stored power is released to supplement; when different ships alternately wait to receive power supply from offshore wind turbines, the power is temporarily stored.

[0038] Among them, in the face of the volatility of offshore wind power input, taking into account the characteristics of the electrolytic cell 5 that the energy efficiency is high but the hydrogen production is slow in the small current range, and the energy efficiency is low but the hydrogen production is fast in the large current range, this embodiment also uses the real-time monitoring and dynamic adjustment method of the working current and energy efficiency of the electrolytic cell 5. When the current is insufficient, the electrolytic cell 5 is supplemented with power through the battery 3, and when the current is too large, part of the excess power is stored through the battery 3, so as to maintain the balance range of the hydrogen production rate and energy efficiency of the electrolytic cell 5 under different wind conditions, and avoid the normal hydrogen production of the electrolytic cell 5 being affected by the instability of the offshore wind power input.

[0039] In some of the embodiments, the hydrogen storage device includes a dryer 7, a compressor 8 and a hydrogen storage tank 9 connected in sequence, the dryer 7 is used to remove moisture from the hydrogen produced by the hydrogen production device, the compressor 8 is used to compress the dried hydrogen, and the hydrogen storage tank 9 is used to store compressed hydrogen.

[0040] In this embodiment, the green hydrogen produced by the electrolytic cell 5 is first dehydrated by the dryer 7, then enters the compressor 8 and is compressed to 35-70Mpa, and finally stored in the hydrogen storage tank 9. Among them, the cost, safety, and difficulty of loading and disassembly of the hydrogen storage tank 9 are very critical. The pressure of traditional steel type I and II gas cylinders is generally below 30MPa, and the hydrogen storage density is only 14-17g / L, while the pressure of carbon fiber or glass fiber type III and IV gas cylinders can reach 30-70MPa, and the hydrogen storage density can reach more than 40 g / L, which is more economical. Therefore, this embodiment adopts two high-pressure hydrogen storage tanks with pressures of 35MPa and 70MPa. The high-pressure hydrogen storage tank can maximize the energy density of hydrogen transportation by pressurizing.

[0041] In the preferred example, this embodiment adopts Type III hydrogen storage tanks, and provides two hydrogen storage tank structures and corresponding loading and unloading modes according to ships with different carrying requirements. Specifically, for small green hydrogen ships, a small mobile hydrogen storage tank is used, multiple hydrogen storage tanks 9 are connected in parallel in a fixed bracket, and a multi-tank multi-filling hydrogenation mode is adopted. All hydrogen storage tanks 9 are filled with hydrogen at the same time using branch pipelines and valve control systems to avoid safety accidents caused by the limited volume of a single tank; after the ship arrives at the dock, the green hydrogen is directly unloaded together with the hydrogen storage tank 9, and the empty tank is replaced on the ship to perform the next sea mission. For large and medium-sized green hydrogen ships, a large fixed hydrogen storage tank is used, and a single tank single-filling hydrogenation mode is adopted. Only a single hydrogen storage tank 9 is refilled each time, and several hydrogen storage tanks 9 are filled in turn; after the ship arrives at the dock, the green hydrogen is input into the local hydrogen transportation pipeline using a pipeline, and the next sea mission is performed after it is exhausted.

[0042] In some embodiments, the green hydrogen ship system also includes a seawater desalination device, which first performs desalination treatment through the seawater desalination device to obtain fresh water, and then performs electrolysis to produce hydrogen. Compared with transporting fresh water from the shore, it reduces transportation costs and can utilize sufficient seawater resources. Among them, the seawater desalination device includes a seawater desalination tank 1 and a filter 103, a sterilizer 104, a reverse osmosis device 105 and an electrodialysis device 106 arranged in the seawater desalination tank 1 and connected in sequence. The seawater desalination tank 1 is provided with a water inlet 101, and the seawater desalination tank 1 extracts seawater through the water inlet 101, and the seawater enters the filter 103, the sterilizer 104, the reverse osmosis device 105 and the electrodialysis device 106 in sequence for desalination treatment.

[0043] Compared with the existing commercial-grade seawater desalination equipment, the seawater desalination equipment of this embodiment has an additional electrodialysis device 106. The commercial-grade seawater desalination equipment can desalinate and purify seawater with high salt content and many impurities into fresh water with higher purity. Among them, multiple treatment processes such as filter 103, sterilizer 104, reverse osmosis membrane, etc. can be used to remove various particles, microorganisms, salt, etc. in seawater, and domestic water with a total dissolved solid content of less than 500ppm can be obtained, thereby meeting the water intake demand of the electrolytic cell 5 and avoiding the huge cost of transporting fresh water from land. However, considering that its final freshwater product still contains 500mg / L of total dissolved solids and Na + , Cl - If the impurity ions such as ions are directly introduced into the electrolytic cell 5, it will not only cause the electrolytic cell 5 to be polluted and deteriorated, but also affect the purity of the produced green hydrogen. Therefore, the seawater desalination device in this embodiment adds an additional electrodialysis device 106 at the rear end of the reverse osmosis device 105, and guides the migration of positive and negative ions by applying an external electric field, thereby obtaining high-purity water that meets the standards of the electrolytic cell 5.

[0044] In a preferred embodiment, a pH control device 6 and a first heat exchanger 10 are added to the rear end of the electrodialysis device 106 to adjust the pure water input to the optimal working condition of the electrolytic cell 5, thereby ensuring its hydrogen production efficiency and purity.

[0045] In some of the embodiments, the green hydrogen ship system also includes a fresh water storage tank 2, a first heat exchanger 10 and a second heat exchanger 11; one end of the fresh water storage tank 2 is connected to the electrodialysis device 106, and the other end of the fresh water storage tank 2 is connected to the electrolytic cell 5; one end of the first heat exchanger 10 is connected to the engine of the ship, and the other end of the first heat exchanger 10 is connected to the fresh water storage tank 2; one end of the second heat exchanger 11 is connected to the engine 18 of the ship, and the other end of the second heat exchanger 11 is connected to the electrolytic cell 5.

[0046] In some of the embodiments, the green hydrogen ship system also includes a power electronic conversion device, the offshore wind power base station includes a wind turbine set, the wind turbine set is used to generate electricity through wind power, and the power electronic conversion device is used to convert the electric energy generated by the wind turbine set into electric energy of the specifications required by the hydrogen production device and the seawater desalination device.

[0047] The power electronic conversion device includes an AC / DC converter 4, a DC / AC converter, a first DC / DC converter and a second DC / DC converter. The power electronic conversion device is used to convert wind power from an offshore wind power base station into electrical energy that can be used by a green hydrogen ship system.

[0048] Among them, the AC / DC converter 4 is used to convert the alternating current generated by the wind turbine into direct current in the DC bus; the DC / AC converter is respectively connected to the DC bus and the seawater desalination device, and is used to convert the direct current in the DC bus into alternating current of the specification required by the seawater desalination device; the first DC / DC converter is respectively connected to the DC bus and the electrolytic cell 5, and is used to convert the direct current in the DC bus into direct current of the specification required by the electrolytic cell 5; the second DC / DC converter is respectively connected to the DC bus and the battery 3, and is used to convert the direct current in the DC bus and store it in the battery 3, and the battery 3 is used to provide living electricity for the ship and for the electrolytic cell 5 to use when shaving peaks and filling valleys.

[0049] like Figure 1As shown, the green hydrogen ship system (in the dotted box) in this embodiment integrates four functions of power electronic conversion, energy quality conversion, energy quality storage and hydrogen shipping in a single ship. The ship can use the AC wind power input of the offshore wind farm, firstly convert it into DC power in the DC bus through the AC / DC converter 4, and then part of the DC power is converted into AC power of the specification required by the seawater desalination device through the DC / AC converter, so as to use the seawater input to produce high-purity fresh water, and supply it to the electrolytic cell 5 or store it in the fresh water storage tank 2. Secondly, part of the DC power in the DC bus is converted into DC power of the specification required by the electrolytic cell 5 through the DC / DC converter, so as to drive the electrolytic cell 5 to decompose the fresh water into hydrogen and oxygen, wherein the hydrogen is compressed to a suitable pressure by the compressor 8 and stored in the high-pressure hydrogen storage tank 9. In addition, part of the DC power in the DC bus is stored in the battery 3 after passing through the DC / DC converter, so as to be used for peak shaving and valley filling of the electrolytic cell 5, and to meet the electricity demand for life on board. After the hydrogen storage tank is full, the produced green hydrogen is transported back to shore for further commercial use by providing fuel input to the ship's power system. In this embodiment, the functional modules related to hydrogen production, storage, and transportation are all integrated inside a single ship, and the required input is only offshore wind power, seawater, and fuel. The entire ship can be completely manufactured and repaired on land, and can be customized according to the capacity of offshore wind turbines. The overall cost is much lower than the currently more commonly used offshore platform hydrogen production and storage solutions.

[0050] The working process of the green hydrogen ship system of this embodiment is described. The green hydrogen ship system of this embodiment is a complex material and energy system, involving the allocation and optimization of material and energy. Figure 2As shown: the input offshore wind power is first converted into direct current of a specific voltage through an AC / DC converter 4, and supplied to the battery 3 and the electrolytic cell 5, wherein the battery 3 mainly plays a role in short-term energy storage and peak regulation to stabilize the power input of the electrolytic cell 5. At the same time, the seawater enters the filter 103, the sterilizer 104, the reverse osmosis device 105 and the electrodialysis device 106 in sequence through the action of the water pump 102, and finally obtains pure water that meets the standards and is stored in the fresh water storage tank 2; in addition, the pH and temperature of the pure water can be further adjusted through the pH control device 6 and the first heat exchanger 10, so that it enters the electrolytic cell 5 in the best state and obtains high-purity hydrogen (about 30 bar pressure) and oxygen. Considering the hull capacity limitation, oxygen will be released directly into the atmosphere, while hydrogen will enter the dryer 7 under the pressure difference, and will be further compressed under the action of the compressor 8, and finally stored in the high-pressure hydrogen storage tank 9. The fully stored green hydrogen is transported back to the nearby dock by the ship engine 18, and then distributed to various land-based hydrogen users 13 by pipeline or truck transportation, thereby completing the closed loop of green hydrogen production, storage, transportation and use. The waste heat from the ship engine can be supplied to the electrolytic cell 5 and the fresh water storage tank 2 respectively through the second heat exchanger 11 and the first heat exchanger 10, so as to improve the energy efficiency of the entire system.

[0051] In order to achieve efficient energy quality allocation, the green hydrogen ship system of this embodiment also involves the construction of a hardware integration system of the "wind turbine-energy storage-hydrogen production" integrated microgrid system, including AC / DC coupling bus coupling technology and system topology, key power electronic converters, battery management systems, energy management systems, key equipment and integration technologies of power quality optimization units in the microgrid system, hardware support technology for ship off-wind operation, and system hardware support technology for ship "wind-storage-hydrogen" integrated operation. In terms of related control software, it mainly involves the integrated power coordination control technology and energy optimization algorithm of "wind turbine + energy storage + hydrogen production" in the green hydrogen ship, including microgrid stability control and event triggering control algorithm under multi-energy coupling conditions, multi-level daytime scheduling and energy optimization control algorithm, hybrid energy-driven grid stability control and fuel optimization algorithm when the ship system is "off-wind" operation, communication protocol between devices in the ship microgrid and control topology design scheme, etc.

[0052] like Figure 3As shown, a specific implementation of an example of a dual hydrogen storage tank ship in the present invention is shown. Corresponding to the offshore wind turbine, the ship system mainly includes three functional modules: hydrogen production, hydrogen storage, and hydrogen transportation. In terms of hydrogen production, the seawater desalination tank 1 extracts seawater through the water inlet 101, and after desalination treatment, the pure water is transported to the electrolytic cell 5 through the internal pipeline. The battery 3 is connected to the offshore wind turbine through the power interface 12, and the DC power processed by the AC / DC converter 4 is obtained, and it is supplied to the seawater desalination device and the electrolytic cell 5 through the internal line. In terms of hydrogen storage, the high-purity hydrogen produced by the electrolytic cell 5 first enters the first high-pressure hydrogen storage tank 901 through the first hydrogen transmission pipeline 24 under the action of the compressor 8, and enters the first high-pressure hydrogen storage tank 902 through the second hydrogen transmission pipeline 25 after the first high-pressure hydrogen storage tank 901 is full. On the sides of the two high-pressure hydrogen storage tanks 9, a first window 28 and a second window 29 are respectively left, which are mainly used for unloading green hydrogen after the ship docks. A first lightning arrester 26 and a second lightning arrester 27 are installed on the top of the two high-pressure hydrogen storage tanks 9, respectively, mainly for preventing thunderstorms at sea. In terms of hydrogen transportation, the ship includes a hull, a cockpit 14, a chimney 15, a steering cabin 16, a propeller 17, an engine 18, a double bottom tank for storing fuel (the first bottom tank 19 and the second bottom tank 21), a cabin for fixing the hydrogen storage tanks 9 (the first cabin 20 and the second cabin 22), and a bulbous bow 23. The ship of this embodiment can adopt a ship of existing design.

[0053] It should be noted that this implementation case is only one feasibility example of the present invention. The relative positions of the hydrogen production, storage and transportation modules can be replaced according to actual needs, the equipment parameters of each module (such as power, energy, capacity, etc.) can be adjusted according to actual needs, and the technical means of each module (such as other electrolytic cell technology, battery technology, seawater desalination technology, hydrogen storage technology, etc.) can also be selected according to actual needs and cost control.

[0054] The embodiment of the present invention further provides an operation method of a green hydrogen production, storage and transportation integrated ship system for offshore wind power, for a system that obtains fresh water by desalination and electrolyzes the fresh water to produce hydrogen, the operation method includes:

[0055] Step S1, a first ship carrying an empty hydrogen storage tank 9 departs from a home port and arrives at a designated offshore wind power base station, anchors the hull of the first ship, and connects the first ship to the offshore wind power base station;

[0056] Step S2, extracting seawater for desalination through the seawater desalination device in the first ship, and storing a certain amount of pure water in the fresh water storage tank 2 in the first ship;

[0057] Step S3, electrolyzing pure water through the electrolytic cell 5 in the first ship, and storing the hydrogen obtained by the electrolysis in the hydrogen storage tank 9 of the first ship;

[0058] Step S4, when the hydrogen storage tank 9 of the first ship reaches the set storage capacity, a second ship carrying an empty hydrogen storage tank 9 departs from the home port, and when the second ship arrives at the offshore wind power base station, the hydrogen storage tank 9 of the first ship is fully filled with hydrogen;

[0059] Step S5, interrupting the power connection between the first ship and the offshore wind power base station, and returning the first ship to the home port, while the second ship anchors the hull and connects to the offshore wind power base station, repeating the work of the first ship.

[0060] Among them, the green hydrogen transported back to the home port can be further transported to the hydrogen use destination in a tank mode or through a third hydrogen pipeline.

[0061] It should be noted that, for a system that directly electrolyzes seawater or electrolyzes fresh water transported from shore, the operating method is similar to the above, except that step S2 is omitted, and in step S3, seawater or fresh water transported from shore is electrolyzed by the electrolytic cell 5 in the first ship.

[0062] In some embodiments, the number of the first ship and the number of the second ship are respectively multiple, that is, there can be multiple ships connected to the offshore wind power base station power interface 12 at the same time, and the number of offshore wind power base stations can also be multiple. Therefore, it can be understood that for a single offshore wind power base station, the number of its power interfaces 12 is greater than or equal to the larger number of the first ship and the second ship.

[0063] In one example, the number of ships required for the same base station interface can be calculated based on the distance from the wind farm to the shore, the ship speed, and the hydrogen production rate. By multiplying the number of ships required for a single base station interface by the total number of base station interfaces, the total number of ships can be obtained, thereby forming a highly efficient offshore wind power hydrogen production ship system.

[0064] Among them, the connection between the first ship and the second ship and the offshore wind power base station includes the power connection between the first ship and the second ship and the offshore wind power base station. In addition, the connection between the ship and the wind turbine after arriving at the wind power base station will also include the handshake communication protocol between the ship and the wind power base station, the power transmission interface between the ship and the wind power base station, the interface overcurrent and overvoltage protection solution, and the ship optimization scheduling strategy algorithm when the ship and the wind power base station are in "many-to-many" operation.

[0065] In one example, the communication connection between the first ship and the second ship and the offshore wind power base station includes the following six stages:

[0066] 1) Physical connection establishment stage: the ship management systems of the first ship and the second ship respectively perform physical switch status detection on the wind turbines of the offshore wind power base station to confirm whether the physical power connection is completed;

[0067] 2) Low-voltage auxiliary power-on stage: After confirming that the physical connection is completed, the wind turbine sends a handshake message to the ship management system and sends the communication protocol version to the ship management system. The ship management system sends a handshake message to the wind turbine and sends its own protection threshold to the wind turbine;

[0068] 3) Ship and wind turbine handshake stage: First, the wind turbine performs a system self-test including insulation detection. After the test is successful, the wind turbine sends a self-test success message to the ship management system; secondly, after receiving the self-test success message, the ship management system sends a feedback message to the wind turbine, and the feedback message includes information confirming receipt of the self-test success message and the communication protocol version, power supply requirements, and identification code information used by the ship management system; finally, after receiving the feedback message, the wind turbine performs an algorithm logic analysis to confirm whether to start power supply;

[0069] 4) Ship hydrogen production parameter configuration stage: the ship charging systems of the first ship and the second ship send their complete parameter information to the wind turbine generator set, and the wind turbine generator set sends a working message to the ship controller of the first ship and the second ship, and the working message includes the power supply capacity constraint and insulation status of the wind turbine generator set; after the ship charging system and the wind turbine generator set confirm the information they have received, they send each other a ready confirmation message and close their respective high-voltage connections;

[0070] 5) Hydrogen production stage of hydrogen-producing ships: First, the ship controller sends a power supply demand message and real-time measurement data to the wind turbine to achieve closed-loop control of the wind turbine; secondly, the wind turbine controls the power supply parameters according to the requirements of the ship controller, and also sends real-time operation information to the ship controller so that it can adjust the requirements; if a fault occurs during the hydrogen production process, a fault protection function needs to be provided, and both parties send each other a stop fault request to stop the power supply;

[0071] 6) End of hydrogen production: The ship controller sends a stop request and sends the final status to the wind turbine. The charging unit confirms the request and sends information such as the wind turbine number, charging time, power, bill, etc. to complete hydrogen production.

[0072] The green hydrogen ship system of this embodiment integrates the hydrogen production and storage modules inside the ship, and realizes the integrated production, storage and transportation of offshore green hydrogen, which greatly reduces the manufacturing cost of the system. As a green hydrogen manufacturing plant, the green hydrogen ship system of this embodiment can be completely produced and transformed in a land shipyard, which greatly reduces the difficulty and risk of manufacturing, and its maintenance and repair can also be carried out after the ship returns to the port, which can avoid high-cost and high-risk sea operations. In addition, the green hydrogen ship system of this embodiment is a modular product, which can accurately calculate the tonnage of the required ship, the power of the electrolytic cell, the capacity of the hydrogen storage tank and other key parameters according to the scale of the offshore wind farm, so as to accurately meet its needs. At the same time, the green hydrogen ship system of this embodiment does not involve centralized large-scale hydrogen storage at sea or on the seabed, and the hydrogen storage capacity of a single ship is limited, which can minimize the risk.

[0073] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. An operation method of an integrated green hydrogen production, storage and transportation ship system for offshore wind power, characterized in that: Based on an integrated ship system for green hydrogen production, storage and transportation for offshore wind power, the integrated ship system for green hydrogen production, storage and transportation for offshore wind power comprises: a ship and a hydrogen production device and a hydrogen storage device arranged in the ship, the hydrogen production device is used to electrolyze seawater or fresh water into hydrogen and oxygen, the hydrogen storage device is used to store the hydrogen produced by the hydrogen production device, and the ship is used to connect to an offshore wind power base station and travel between the offshore wind power base station and a home port; the hydrogen production device comprises an electrolytic cell (5), the integrated ship system for green hydrogen production, storage and transportation for offshore wind power further comprises a second heat exchanger (11), one end of the second heat exchanger (11) is connected to an engine (18) of the ship, and the other end of the second heat exchanger (11) is connected to the electrolytic cell (5); the hydrogen storage device comprises a hydrogen storage tank (9), and the integrated ship system for green hydrogen production, storage and transportation for offshore wind power further comprises a seawater desalination device and a fresh water storage tank (2); The operation method of the green hydrogen production, storage and transportation integrated ship system for offshore wind power includes: Step S1, a first ship carrying an empty hydrogen storage tank (9) departs from a home port and arrives at a designated offshore wind power base station, anchors the hull of the first ship, and connects the first ship to the offshore wind power base station; Step S2, extracting seawater for desalination through the seawater desalination device in the first ship, and storing a fixed amount of pure water in the fresh water storage tank (2) in the first ship; Step S3, electrolyzing pure water through the electrolytic cell (5) in the first ship, and storing hydrogen obtained by the electrolysis in a hydrogen storage tank (9) of the first ship; Step S4, when the hydrogen storage tank (9) of the first ship reaches a set storage capacity, a second ship carrying an empty hydrogen storage tank (9) departs from the home port, and when the second ship arrives at the offshore wind power base station, the hydrogen storage tank (9) of the first ship is fully filled with hydrogen; Step S5, interrupting the power connection between the first ship and the offshore wind power base station, and returning the first ship to the home port, while the second ship anchors the hull and connects to the offshore wind power base station, repeating the work of the first ship.

2. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 1 is characterized in that: The electrolytic cell (5) is connected to the hydrogen storage device via a first hydrogen transmission pipeline (24).

3. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 2 is characterized in that: The hydrogen storage device comprises a drier (7), a compressor (8) and a hydrogen storage tank (9) which are connected in sequence, the drier (7) being used to remove moisture from the hydrogen produced by the hydrogen production device, the compressor (8) being used to compress the dried hydrogen, and the hydrogen storage tank (9) being used to store the compressed hydrogen.

4. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 3 is characterized in that: The seawater desalination device comprises a seawater desalination tank (1), and a filter (103), a sterilizer (104), a reverse osmosis device (105), and an electrodialysis device (106) which are arranged in the seawater desalination tank (1) and are connected in sequence. The seawater desalination tank (1) is provided with a water inlet (101), and the seawater desalination tank (1) draws seawater through the water inlet (101). The seawater enters the filter (103), the sterilizer (104), the reverse osmosis device (105), and the electrodialysis device (106) in sequence for desalination treatment.

5. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 4 is characterized in that: The green hydrogen production, storage and transportation integrated ship system for offshore wind power further comprises a first heat exchanger (10); one end of the fresh water storage tank (2) is connected to the electrodialysis device (106), and the other end of the fresh water storage tank (2) is connected to the electrolytic cell (5); one end of the first heat exchanger (10) is connected to the engine (18) of the ship, and the other end of the first heat exchanger (10) is connected to the fresh water storage tank (2).

6. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to any one of claims 1 to 5, characterized in that: The integrated green hydrogen production, storage and transportation ship system for offshore wind power also includes a power electronic conversion device. The offshore wind power base station includes a wind turbine group, which is used to generate electricity through wind power. The power electronic conversion device is used to convert the electric energy generated by the wind turbine group into electric energy of the specifications required by the hydrogen production device and the seawater desalination device.

7. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 6 is characterized in that: The power electronic conversion device comprises: An AC / DC converter (4) is used to convert the alternating current generated by the wind turbine into direct current in a DC bus; A DC / AC converter, connected to the DC bus and the seawater desalination device, respectively, for converting the DC power in the DC bus into AC power of the specification required by the seawater desalination device; A first DC / DC converter, connected to the DC bus and the electrolytic cell (5), respectively, and used to convert the DC power in the DC bus into DC power of a specification required by the electrolytic cell (5); The second DC / DC converter is connected to the DC bus and the storage battery (3) respectively, and is used to convert the DC power in the DC bus and store it in the storage battery (3); the storage battery (3) is used to provide domestic electricity for the ship and to be used by the electrolytic cell (5) for peak load shaving and valley filling.

8. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 1 is characterized in that: The number of the first ships and the number of the second ships are respectively plural, and the number of the power interfaces (12) of the offshore wind power base station is greater than or equal to the larger number of the first ships and the second ships.

9. The method for operating the green hydrogen production, storage and transportation integrated ship system for offshore wind power according to claim 1 is characterized in that: The connection between the first ship and the second ship and the offshore wind power base station includes: power connection and communication connection between the first ship and the second ship and the offshore wind power base station, wherein the communication connection between the first ship and the second ship and the offshore wind power base station is based on a handshake communication protocol.

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