Offshore wind power generation and hydrogen electricity combined transmission system based on superconducting technology

Abstract

The application discloses a kind of offshore wind power generation and hydrogen electricity combined transport system based on superconducting technology, including offshore superconducting wind power generation system, the electric energy output by offshore superconducting wind power generation system is gathered to offshore platform by submarine power collection cable and submarine power collection cable of liquid hydrogen cooling pipeline system, and is converted into stable direct current by first voltage conversion system;Offshore liquid hydrogen preparation system utilizes a part of stable direct current to prepare liquid hydrogen, a part of liquid hydrogen is introduced into submarine power collection cable and liquid hydrogen cooling pipeline of liquid hydrogen cooling pipeline system after being pressurized and cooled, to provide cooling for superconducting fan in turn, and the remaining liquid hydrogen is transported to superconducting outlet system through mixed energy pipeline using active gasification temperature control technology with the remaining stable direct current, and the electric power of superconducting outlet system is transmitted to national power grid through second voltage conversion system, and the liquid hydrogen of superconducting outlet system is stored, transported and sold;The application reduces the investment cost of offshore superconducting fan cooling system.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, and more specifically to a combined offshore wind power generation and hydrogen-electricity transmission system based on superconducting technology. Background Technology

[0002] Among renewable energy generation technologies, wind power is the fastest-growing energy technology in the world. Larger wind turbines capture more wind energy and have lower installation and maintenance costs. Compared to onshore wind farms, offshore wind farms are becoming increasingly popular due to their smaller installation space constraints and higher average wind speeds. In recent years, high-power wind turbines have become the mainstream demand in the offshore wind turbine market. However, large wind turbine units are mainly composed of copper wire, stator, and rotor cores, resulting in significant weight and volume. Installation difficulty and maintenance costs are key issues, prompting many organizations to attempt to develop wind turbines with larger capacity, smaller size, and lighter weight.

[0003] Superconducting wind turbines are lightweight, compact, and have high power density, making their application in wind power generation a current trend. Unlike conventional wind turbines, superconducting wind turbines require cryogenic cooling for normal operation. For a single superconducting wind turbine, equipment such as chillers can be mounted on the rotor hub, while refrigerant storage tanks and compressors can be installed externally. This method of equipping each unit with an independent cooling system not only requires huge investment costs but also faces many technical challenges. Furthermore, the intermittent and highly random nature of offshore wind power generation poses numerous challenges to the safe and reliable integration of offshore wind power. In the future, constrained by grid expansion, the development of offshore wind farms may be hindered and may experience severe reductions or restrictions as the penetration rate of renewable energy in the grid increases. On the other hand, as the distance of offshore wind farms from shore continues to increase, the power loss caused by long-distance transmission also becomes a significant issue. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention aims to provide a superconducting offshore wind power generation and hydrogen-electricity combined transmission system. This system simplifies the cooling system of offshore superconducting wind turbines by using liquid hydrogen circulation cooling to reduce investment costs. At the same time, it obtains both electricity and liquid hydrogen through superconducting hybrid energy pipelines, solving problems such as offshore wind farm expansion, waste power recovery, and energy storage.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A superconducting offshore wind power generation and hydrogen-electricity co-transmission system includes an offshore superconducting wind power generation system 1. The electrical energy output from the offshore superconducting wind power generation system 1 is collected by the submarine power collection cable and the liquid hydrogen cooling pipeline system 2 to an offshore platform, and converted into stable DC power by a first transformer conversion system 3-1. An offshore liquid hydrogen production system 4 uses a portion of the stable DC power to produce liquid hydrogen. After passing through a pressurization and cooling system 5, a portion of the liquid hydrogen is fed into the submarine power collection cable and the liquid hydrogen cooling pipeline system 2 to provide cooling for the superconducting wind turbine. The remaining liquid hydrogen is transported together with the remaining stable DC power through a superconducting access system 6 and a hybrid energy pipeline 7 using active vaporization temperature control technology to a superconducting output system 8. The electricity from the superconducting output system 8 is transmitted to the national grid through a second transformer conversion system 3-2. The liquid hydrogen from the superconducting output system 8 is stored, transported, and sold.

[0007] The offshore superconducting wind power generation system 1 includes an offshore superconducting wind turbine 11 and an AC / DC / AC converter 12. The electrical energy output by the superconducting wind turbine 11 is rectified by the AC / DC converter in the AC / DC / AC converter 12, inverted by the DC / AC converter, and stepped up by the transformer before being connected to the submarine power collection cable and liquid hydrogen cooling pipeline system 2, and connected to the first transformer conversion system 3-1 of the offshore platform.

[0008] The first transformer conversion system 3-1 includes an AC / DC converter 31 and a transformer 32. The electrical energy collected by the submarine power collection cable and the liquid hydrogen cooling pipeline system 2 is converted into stable DC power by the AC / DC converter 31, then the voltage is boosted by the transformer 32, and finally connected to the hybrid energy pipeline 7 with active gasification temperature control technology to land via the superconducting access system 6.

[0009] The offshore liquid hydrogen production system 4 includes a seawater desalination unit 41, a PEM electrolysis water hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43 connected in sequence. Liquid hydrogen is produced using stable DC power from the offshore platform. After passing through the pressurization and cooling system 5, a portion of the liquid hydrogen is fed into the submarine current collection cable and liquid hydrogen cooling pipeline system 2 to provide cooling for the superconducting fan 11. The remaining liquid hydrogen is transported to the superconducting output system 8 through the hybrid energy pipeline 7, which adopts active vaporization temperature control technology.

[0010] The submarine power collection cable and liquid hydrogen cooling pipeline system 2 includes two layout schemes: centralized hydrogen production + circulating cooling and distributed hydrogen production + unidirectional cooling. In both schemes, the submarine power collection cable and liquid hydrogen cooling pipeline are arranged adjacent to each other and in parallel.

[0011] The submarine current collection cable and liquid hydrogen cooling pipeline system 2 adopts a centralized hydrogen production + circulating cooling layout scheme, namely a circulating submarine current collection cable and liquid hydrogen cooling pipeline system, including an offshore platform 21, a submarine current collection cable 22, and a liquid hydrogen cooling pipeline 23. A seawater desalination unit 41, a PEM electrolysis water hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43 are sequentially connected to continuously produce liquid hydrogen on the offshore platform 21. A liquid hydrogen booster pump 51 and a helium refrigerator 52 are connected to pressurize and cool the produced liquid hydrogen. Then, a portion of the liquid hydrogen is passed into the liquid hydrogen cooling pipeline 23 to provide cooling for the superconducting fan 11, and then circulated back to the offshore platform 21. If the liquid hydrogen obtains pressure in the pressurization and cooling system 5... The supercooling is insufficient to support complete flow and cooling within the liquid hydrogen cooling pipe 23, so a liquid hydrogen booster pump 51 and a helium refrigerator 52 need to be added in the middle. The electrical energy output by the superconducting fan 11 is connected to the submarine power collection cable 22 adjacent to and parallel to the liquid hydrogen cooling pipe 23 and transmitted bidirectionally to the offshore platform 21. Then it is connected to the AC / DC converter 31 to be converted into stable DC power. Part of the DC power is connected to the power input terminals of the seawater desalination unit 41, the PEM water electrolysis hydrogen production and purification unit 42, and the hydrogen liquefaction unit 43. The remaining DC power is connected to the hybrid energy pipe 7, which adopts active gasification temperature control technology, after the voltage is boosted by the transformer 32.

[0012] In the circulating submarine power collection cable and liquid hydrogen cooling pipeline system 2, the submarine power collection cable 22 and the liquid hydrogen cooling pipeline 23 are arranged adjacently and in parallel. The submarine power collection cable 22 adopts a bidirectional ring structure. Under normal operation, the electrical energy output by the superconducting fan 11 is collected along the submarine power collection cable 22 to the offshore platform 21. If a fault occurs at any point in the submarine power collection cable 22, the submarine power collection cables 22 on both sides of the fault point can still collect the electrical energy output by the superconducting fan 11 to the offshore platform 21. The liquid hydrogen cooling pipeline 23 is arranged in parallel with the submarine power collection cable 22. Liquid hydrogen is introduced from the offshore platform 21 into the liquid hydrogen cooling pipeline 23, and after cooling the superconducting fan 11, it finally returns to the offshore platform 21. A large offshore superconducting wind farm is designed with one or more offshore platforms 21. Multiple circulating submarine power collection cable and liquid hydrogen cooling pipeline systems 2 need to be set up around each offshore platform 21 to achieve cooling of all superconducting fans 11 and collection of electrical energy.

[0013] The submarine power collection cable and liquid hydrogen cooling pipeline system 2 adopts a distributed hydrogen production + unidirectional cooling layout scheme, namely a unidirectional submarine power collection cable and liquid hydrogen cooling pipeline system, including an offshore liquid hydrogen production platform 24, a submarine power collection cable 22, a liquid hydrogen cooling pipeline 23, and an offshore platform 21. A seawater desalination unit 41, a PEM electrolysis water hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43 are sequentially connected, continuously producing liquid hydrogen on the offshore liquid hydrogen production platform 24. The required electrical energy is provided by a superconducting fan 11 near the offshore liquid hydrogen production platform 24. A liquid hydrogen booster pump 51 and a helium refrigerator 52 are connected to pressurize and cool the produced liquid hydrogen. The liquid hydrogen cooling pipe 23 then provides cooling for the superconducting fan 11 and is transported to the offshore platform 21 along the liquid hydrogen cooling pipe 23. If the pressure and subcooling of the liquid hydrogen obtained in the pressurization and cooling system 5 are insufficient to support its complete flow and cooling in the liquid hydrogen cooling pipe 23, a liquid hydrogen booster pump 51 and a helium refrigerator 52 need to be added in the middle. The electrical energy output by the superconducting fan 11 is connected to the submarine power collection cable 22 and transported unidirectionally to the offshore platform 21. It is converted into stable DC power by the AC / DC converter 31, and then the voltage is boosted by the transformer 32 before being connected to the hybrid energy pipe 7 which adopts active vaporization temperature control technology.

[0014] In the unidirectional submarine current collector cable and liquid hydrogen cooling pipeline system 2, the submarine current collector cable 22 and the liquid hydrogen cooling pipeline 23 are arranged as adjacent and parallel as possible. The submarine current collector cable 22 adopts a branch-chain structure to reduce investment costs. A genetic algorithm is used to find the appropriate topology for the submarine current collector cable 22 with the goal of minimizing investment costs. The liquid hydrogen cooling pipeline 23 adopts a chain structure. Liquid hydrogen enters the liquid hydrogen cooling pipeline 23 from the offshore liquid production platform 24, cools the superconducting fan 11, and is finally transported to the offshore platform 21. Due to the location limitations of the offshore liquid production platform 24, the liquid hydrogen cooling pipeline 23 cannot be arranged completely adjacent and parallel to the submarine current collector cable 22. One arrangement scheme adopted is... In the submarine power collection cable 22 with a branch-chain structure, a chain line is found that is close to as many superconducting wind turbines 11 as possible, and liquid hydrogen cooling pipes 23 are arranged along this line; another arrangement scheme is to disregard the existing branch-chain structure of the submarine power collection cable 22 and find a new chain line to arrange the liquid hydrogen cooling pipes 23, but the chain line should overlap with as many submarine power collection cables 22 as possible; a large offshore superconducting wind farm is designed with one or more offshore platforms 21. Around each offshore platform 21, multiple unidirectional submarine power collection cable and liquid hydrogen cooling pipe systems 2 starting from the offshore liquid production platform 24 need to be set up to achieve cooling of the superconducting wind turbines 11 and collection of electrical energy.

[0015] The superconducting access system 6 includes a first copper wire cable 61, a first insulation layer 62, a liquid hydrogen precooling box 63, a liquid hydrogen injection port 64, and an inlet superconducting cable 65. It is used to complete the conversion of the first copper wire cable 61 to the inlet superconducting cable 65 and to serve as the injection port for liquid hydrogen in the hybrid energy pipeline. The first copper wire cable 61 and the inlet superconducting cable 65 are converted in the liquid hydrogen precooling box 63, and liquid hydrogen is used as a precooling agent. The prepared liquid hydrogen is pressurized by the liquid hydrogen booster pump 51 and subcooled by the helium refrigerator 52, and then injected into the hybrid energy pipeline 7, which adopts active vaporization temperature control technology, through the liquid hydrogen injection port 64.

[0016] The hybrid energy pipeline 7, employing active vaporization temperature control technology, is divided into a normal section and a temperature-controlled section along its length. The first section, comprising 80%-90% of the total pipeline length, is the normal section, including a superconducting cable arranged coaxially from the inside out, a liquid hydrogen transport channel 74, and a vacuum insulation layer 75. The second section, comprising 10%-20% of the total pipeline length, is the temperature-controlled section, including a superconducting cable arranged coaxially from the inside out, a liquid hydrogen transport channel 74, a liquid hydrogen active vaporization auxiliary channel 76, and a vacuum insulation layer 75. The superconducting cable includes a copper skeleton 71, a superconducting layer 72, an electrical insulation layer, and a shielding layer 73 arranged coaxially from the inside out. The cross-sectional dimensions of the superconducting cable and the liquid hydrogen transport channel 74 are identical throughout the entire pipeline. The superconducting cable is always positioned at the center of the liquid hydrogen transport channel 74 and supported by cable pulleys. The liquid hydrogen transport channel 74 is located in the normal section of the hybrid energy pipeline. The outer side of the delivery channel 74 is a vacuum insulation layer 75. The outer side of the liquid hydrogen delivery channel 74 in the temperature control section of the hybrid energy pipeline is, in sequence, a liquid hydrogen active vaporization auxiliary channel 76 and a vacuum insulation layer 75. Multiple injection holes 77 are opened on the pipe wall between the liquid hydrogen delivery channel 74 and the liquid hydrogen active vaporization auxiliary channel 76. The injection volume of each injection hole is 1 / 100 of the mass flow rate of liquid hydrogen in the liquid hydrogen delivery channel 74. After the liquid hydrogen is injected into the liquid hydrogen active vaporization auxiliary channel 76 from the liquid hydrogen delivery channel 74 through the injection holes 77, its own pressure decreases and it reaches the vaporization temperature. Thereafter, the liquid hydrogen will actively vaporize during the flow process in the liquid hydrogen active vaporization auxiliary channel 76 and release its own latent heat. It not only absorbs the heat input from the external environment through the vacuum insulation layer 75, but the remaining cold energy also reduces the temperature of the liquid hydrogen in the liquid hydrogen delivery channel 74, thereby achieving the effect of temperature control.

[0017] The superconducting exit system 8 includes an outlet superconducting cable 81, a hydrogen emission port 82, a liquid hydrogen emission port 83, a hydrogen precooling box 84, a second insulation layer 85, and a second copper wire cable 86. It is used to complete the conversion of the outlet superconducting cable 81 to the second copper wire cable 86, and serves as the emission port of the liquid hydrogen transport channel 74 and the liquid hydrogen active vaporization auxiliary channel 76 in the hybrid energy pipeline. The outlet superconducting cable 81 and the second copper wire cable 86 are converted in the hydrogen precooling box 84, and the low-temperature hydrogen in the liquid hydrogen active vaporization auxiliary channel 76 is used as a precooling agent.

[0018] Compared with the prior art, the positive effects of the present invention are:

[0019] This invention, based on superconducting technology, proposes an integrated offshore superconducting wind-hydrogen system that combines offshore wind farm power collection, offshore wind power liquid hydrogen production, superconducting wind turbine cooling, and hydrogen-electric hybrid energy transmission. The system utilizes the electrical energy output from the superconducting wind turbine to centrally produce liquid hydrogen on an offshore platform. The liquid hydrogen is then sequentially cooled by liquid hydrogen pipelines running parallel to and adjacent to the submarine power collection cables. This avoids additional subsea construction and significantly simplifies the cooling system for the superconducting wind turbine. Furthermore, liquid hydrogen cooling reduces the number of helium refrigerators required, and the selected superconducting material can be MgB2, which is far less expensive than high-temperature superconducting materials, thus significantly reducing the investment cost of offshore superconducting wind farms.

[0020] Superconducting direct current (DC) transmission technology has near-zero DC losses, which minimizes energy loss during transmission to only 0.5% of the transmitted power. Therefore, establishing a hydrogen-electric hybrid pipeline based on superconducting technology to jointly transmit electricity and liquid hydrogen not only reduces capital investment but also lowers operating costs. This is the optimal transportation solution for integrating offshore wind power and the hydrogen energy industry, while also solving problems such as offshore wind farm expansion, wastewater recovery, and energy storage. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0022] Figure 2 This is a schematic diagram of the circulating submarine current collection cable and liquid hydrogen cooling pipeline system of the present invention.

[0023] Figure 3 This is a topology diagram illustrating an application example of the circulating submarine current collection cable and liquid hydrogen cooling pipeline system of the present invention.

[0024] Figure 4 This is a schematic diagram of the unidirectional submarine current collection cable and liquid hydrogen cooling pipeline system of the present invention.

[0025] Figure 5 This is a topology diagram illustrating an application example of the unidirectional submarine current collection cable and liquid hydrogen cooling pipeline system of the present invention.

[0026] Figure 6 This is a schematic diagram of the superconducting access system structure of the present invention.

[0027] Figure 7 This is a schematic diagram of the hybrid energy pipeline structure using active gasification temperature control technology according to the present invention.

[0028] Figure 8 This is a schematic diagram of the superconducting connection system of the present invention. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the embodiments and accompanying drawings.

[0030] like Figure 1 As shown, an offshore wind power generation and hydrogen-electricity co-transmission system based on superconducting technology includes an offshore superconducting wind power generation system 1, a submarine power collection cable and liquid hydrogen cooling pipeline system 2, a first transformer conversion system 3-1, a second transformer conversion system 3-2, an offshore liquid hydrogen production system 4, a pressurization and cooling system 5, a superconducting access system 6, a hybrid energy pipeline 7 employing active vaporization temperature control technology, and a superconducting output system 8. The electrical energy output from the offshore superconducting wind power generation system 1 is collected to the offshore platform via the submarine power collection cable and liquid hydrogen cooling pipeline system 2, and then converted by the first transformer conversion system. System 3-1 converts to stable direct current; the offshore liquid hydrogen production system 4 uses a portion of the stable direct current to produce liquid hydrogen. After passing through the pressurization and cooling system 5, a portion of the liquid hydrogen is fed into the submarine current collection cable and liquid hydrogen cooling pipeline system 2 to provide cooling for the superconducting fan. The remaining liquid hydrogen is transported to the superconducting output system 8 via the superconducting access system 6 and the remaining stable direct current through the hybrid energy pipeline 7, which uses active vaporization temperature control technology. The electricity from the superconducting output system 8 is transmitted to the national grid via the second transformer conversion system 3-2. The liquid hydrogen from the superconducting output system 8 is stored, transported, and sold.

[0031] like Figure 1 , Figure 2 , Figure 4 As shown, the offshore superconducting wind power generation system 1 includes an offshore superconducting wind turbine 11 and an AC / DC / AC converter 12. The electrical energy output by the superconducting wind turbine 11 is rectified by the AC / DC converter in the AC / DC / AC converter 12, inverted by the DC / AC converter, and stepped up by the transformer before being connected to the submarine power collection cable and liquid hydrogen cooling pipeline system 2, and connected to the first transformer conversion system 3-1 of the offshore platform.

[0032] The submarine power collection cable and liquid hydrogen cooling pipeline system 2 includes two layout schemes: centralized hydrogen production + circulating cooling and distributed hydrogen production + unidirectional cooling. In both schemes, the submarine power collection cable and liquid hydrogen cooling pipeline are arranged adjacent to each other and in parallel.

[0033] The first transformer conversion system 3-1 includes an AC / DC converter 31 and a transformer 32. The electrical energy collected by the submarine power collection cable and the liquid hydrogen cooling pipeline system 2 is converted into stable DC power by the AC / DC converter 31, then the voltage is boosted by the transformer 32, and finally connected to the hybrid energy pipeline 7 using active gasification temperature control technology through the superconducting access system 6.

[0034] like Figure 2As shown, the offshore liquid hydrogen production system 4 includes a seawater desalination unit 41, a PEM electrolysis water hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43 connected in sequence. Liquid hydrogen is produced using stable DC power from the offshore platform. After passing through the pressurization and cooling system 5, a portion of the liquid hydrogen is fed into the submarine current collection cable and liquid hydrogen cooling pipeline system 2 to provide cooling for the superconducting fan 11. The remaining liquid hydrogen is transported to the superconducting output system 8 through the hybrid energy pipeline 7, which adopts active vaporization temperature control technology.

[0035] like Figure 2 As shown, the submarine power collection cable and liquid hydrogen cooling pipeline system 2 adopts a centralized hydrogen production + circulating cooling layout scheme, namely a circulating submarine power collection cable and liquid hydrogen cooling pipeline system, including an offshore platform 21, a submarine power collection cable 22, and a liquid hydrogen cooling pipeline 23. A seawater desalination unit 41, a PEM electrolysis water hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43 are connected in sequence to continuously produce liquid hydrogen on the offshore platform 21. In the pressurization and cooling system 5, a liquid hydrogen booster pump 51 and a helium refrigerator 52 are connected to pressurize and cool the produced liquid hydrogen. The liquid hydrogen is then passed into the liquid hydrogen cooling pipeline 23 to provide cooling for the superconducting fan 11, and then circulated back to the offshore platform 21. If the liquid hydrogen obtains pressure in the pressurization and cooling system 5... The supercooling is insufficient to support complete flow and cooling within the liquid hydrogen cooling pipe 23, so a liquid hydrogen booster pump 51 and a helium refrigerator 52 need to be added in the middle. The electrical energy output by the superconducting fan 11 is connected to the submarine power collection cable 22 adjacent to and parallel to the liquid hydrogen cooling pipe 23 and transmitted bidirectionally to the offshore platform 21. Then, it is connected to the AC / DC converter 31 on the offshore platform 21 to be converted into DC power. Part of the DC power can be connected to the power input terminals of the seawater desalination unit 41, the PEM water electrolysis hydrogen production and purification unit 42, and the hydrogen liquefaction unit 43. The remaining DC power is connected to the hybrid energy pipe 7, which adopts active gasification temperature control technology, after the voltage is boosted by the transformer 32.

[0036] like Figure 3As shown, in the circulating submarine power collection cable and liquid hydrogen cooling pipeline system 2, the submarine power collection cable 22 and the liquid hydrogen cooling pipeline 23 are arranged adjacently and in parallel, which can reduce the workload of submarine operations. Among them, the submarine power collection cable 22 adopts a bidirectional ring structure, which can significantly improve the redundancy of the power collection system. Under normal operation, the electrical energy output by the superconducting fan 11 can be collected along the submarine power collection cable 22 to the offshore platform 21. When a fault occurs at any point in the submarine power collection cable 22, the submarine power collection cables 22 on both sides of the fault point can still transmit power from the superconducting fan 11. The generated electrical energy is collected at the offshore platform 21; the liquid hydrogen cooling pipe 23 runs parallel to the submarine power collection cable 22, and liquid hydrogen is introduced from the offshore platform 21 into the liquid hydrogen cooling pipe 23. After cooling the superconducting wind turbine 11 with liquid hydrogen, it eventually returns to the offshore platform 21; a large offshore superconducting wind farm can be designed with one or more offshore platforms 21. Around each offshore platform 21, multiple circulating submarine power collection cables and liquid hydrogen cooling pipe systems 2 need to be set up to achieve cooling of all superconducting wind turbines 11 and collection of electrical energy.

[0037] like Figure 4 As shown, the submarine power collection cable and liquid hydrogen cooling pipeline system 2 adopts a distributed hydrogen production + unidirectional cooling layout scheme, namely a unidirectional submarine power collection cable and liquid hydrogen cooling pipeline system, including an offshore liquid hydrogen production platform 24, a submarine power collection cable 22, a liquid hydrogen cooling pipeline 23, and an offshore platform 21. A seawater desalination unit 41, a PEM water electrolysis hydrogen production and purification unit 42, and a hydrogen liquefaction unit 43, connected sequentially, can continuously produce liquid hydrogen on the offshore liquid hydrogen production platform 24. The required electrical energy is provided by a superconducting fan 11 near the offshore liquid hydrogen production platform 24. In the pressurization and cooling system 5, the liquid hydrogen booster pump 51 and the helium refrigerator 52 are connected, which can provide... The prepared liquid hydrogen is pressurized and cooled, and then passed through the liquid hydrogen cooling pipe 23 to provide cooling for the superconducting fan 11, and finally transported to the offshore platform 21. If the pressure and subcooling of the liquid hydrogen in the pressurization and cooling system 5 are insufficient to support its complete flow and cooling in the liquid hydrogen cooling pipe 23, a liquid hydrogen booster pump 51 and a helium refrigerator 52 need to be added in the middle. The electrical energy output by the superconducting fan 11 is connected to the submarine power collection cable 22 and transmitted unidirectionally to the offshore platform 21. It is converted into DC power by the AC / DC converter 31, and then the voltage is boosted by the transformer 32 before being connected to the hybrid energy pipe 7 which adopts active vaporization temperature control technology.

[0038] like Figure 5As shown, in the unidirectional submarine power collection cable and liquid hydrogen cooling pipeline system 2, the submarine power collection cable 22 and the liquid hydrogen cooling pipeline 23 are arranged as adjacent and parallel as possible, which can reduce the workload of submarine operations. Among them, the submarine power collection cable 22 adopts a branch-chain structure, which can significantly reduce the investment cost of the power collection system. The genetic algorithm is used to find a suitable power collection cable topology with the goal of minimizing investment cost. The liquid hydrogen cooling pipeline 23 adopts a chain structure. Liquid hydrogen enters the liquid hydrogen cooling pipeline 23 from the offshore liquid production platform 24. After the superconducting fan 11 is cooled by liquid hydrogen, it is finally transported to the offshore platform 21. Due to the location limitations of the offshore liquid production platform 24, it is not possible to arrange the liquid hydrogen cooling pipes 23 in a completely parallel manner adjacent to the submarine power collection cable 22. One possible arrangement is to find a chain line in the submarine power collection cable 22 with a branch-chain structure that is close to as many superconducting fans 11 as possible, and arrange the liquid hydrogen cooling pipes 23 along this line. The disadvantage of this arrangement is that it cannot provide cooling for all superconducting fans 11 in the wind farm. Superconducting fans 11 that cannot be cooled need to be equipped with independent cooling systems or installed as ordinary fans. In order to provide liquid hydrogen cooling for more superconducting fans 11, another possible arrangement is to disregard the existing branch-chain structure of the submarine power collection cable 22 and find a new chain line to arrange the liquid hydrogen cooling pipes 23. However, the chain line should overlap with as many submarine power collection cables 22 as possible to minimize the cost of submarine operations. The disadvantage of this arrangement is that there are some separate submarine power collection cable 22 or liquid hydrogen cooling pipe 23 lines, which inevitably increases the amount of submarine laying work. A large offshore superconducting wind farm can be designed with one or more offshore platforms 21. Around each offshore platform 21, multiple unidirectional submarine power collection cables and liquid hydrogen cooling pipeline systems 2 starting from the offshore liquid production platform 24 are required to achieve cooling of the superconducting wind turbine 11 and collection of electrical energy.

[0039] like Figure 6 As shown, the superconducting access system 6 includes a first copper wire cable 61, a first insulation layer 62, a liquid hydrogen precooling box 63, a liquid hydrogen injection port 64, and an inlet superconducting cable 65. It is used to complete the conversion of the first copper wire cable 61 to the inlet superconducting cable 65 and to serve as the injection port for liquid hydrogen in the hybrid energy pipeline. In order to achieve the low temperature conditions during the conversion process and reduce heat leakage at the inlet of the hybrid energy pipeline, the first copper wire cable 61 and the inlet superconducting cable 65 are converted in the liquid hydrogen precooling box 63, and liquid hydrogen is used as a precooling agent. The liquid hydrogen prepared on the offshore platform is pressurized by the liquid hydrogen booster pump 51 and subcooled by the helium refrigerator 52, and then injected into the hybrid energy pipeline 7, which adopts active vaporization temperature control technology, through the liquid hydrogen injection port 64.

[0040] like Figure 7As shown, the hybrid energy pipeline 7, employing active vaporization temperature control technology, is divided into a normal section and a temperature-controlled section along its length. The front section (80%-90% of the total length) is the normal section, including a superconducting cable arranged coaxially from the inside out, a liquid hydrogen transport channel 74, and a vacuum insulation layer 75. The rear section (10%-20% of the total length) is the temperature-controlled section, including a superconducting cable arranged coaxially from the inside out, a liquid hydrogen transport channel 74, a liquid hydrogen active vaporization auxiliary channel 76, and a vacuum insulation layer 75. The superconducting cable includes a copper skeleton 71, a superconducting layer 72, an electrical insulation layer, and a shielding layer 73 arranged coaxially from the inside out. The cross-sectional dimensions of the superconducting cable and the liquid hydrogen transport channel 74 are identical throughout. The superconducting cable is always positioned at the center of the liquid hydrogen transport channel 74 and supported by cable pulleys. This arrangement ensures that the superconducting cable is always in the optimal heat dissipation position within the liquid hydrogen transport channel 74 and avoids changes in the cable's position. The problem of increased liquid hydrogen flow resistance is addressed by the following: In the ordinary section of the hybrid energy pipeline, the liquid hydrogen transport channel 74 is surrounded by a vacuum insulation layer 75. In the temperature-controlled section of the hybrid energy pipeline, the liquid hydrogen transport channel 74 is surrounded by an active liquid hydrogen vaporization auxiliary channel 76 and a vacuum insulation layer 75, respectively. Multiple injection holes 77 are provided on the pipe wall between the liquid hydrogen transport channel 74 and the active liquid hydrogen vaporization auxiliary channel 76, with a certain distance between adjacent injection holes. The injection volume of each injection hole is approximately 1 / 100 of the liquid hydrogen mass flow rate within the liquid hydrogen transport channel 74. After liquid hydrogen is injected from the liquid hydrogen transport channel 74 through the injection holes 77 into the active liquid hydrogen vaporization auxiliary channel 76, its pressure decreases, reaching the vaporization temperature. Subsequently, the liquid hydrogen actively vaporizes during its flow within the active liquid hydrogen vaporization auxiliary channel 76, releasing its latent heat. This not only absorbs the heat input from the external environment through the vacuum insulation layer 75, but the remaining cooling energy also reduces the temperature of the liquid hydrogen within the liquid hydrogen transport channel 74, thus achieving temperature control.

[0041] The superconductor 72 is made of MgB2, which is more cost-effective. The materials for the electrical insulation layer and shielding layer 73 can be inorganic materials such as glass, ceramics, and mica, or organic materials such as cross-linked polyethylene, polytetrafluoroethylene, and polyimide. The liquid hydrogen transport channel 74 and the liquid hydrogen active vaporization auxiliary channel 76 are made of seamless stainless steel pipes. The vacuum insulation layer 75 adopts high-vacuum multi-layer insulation technology. The material used is aluminum foil with a reflector of 0.006 mm, and 0.1 mm thick cellophane is used as a spacer. The interlayer is filled with activated carbon adsorbent or molecular sieve to adsorb gas, thereby ensuring the vacuum degree in the vacuum insulation layer.

[0042] like Figure 8As shown, the superconducting outlet system 8 includes an outlet superconducting cable 81, a hydrogen emission port 82, a liquid hydrogen emission port 83, a hydrogen precooling box 84, a second insulation layer 85, and a second copper wire cable 86. It is used to complete the conversion of the outlet superconducting cable 81 to the second copper wire cable 86, and serves as the emission port of the liquid hydrogen transport channel 74 and the liquid hydrogen active vaporization auxiliary channel 76 in the hybrid energy pipeline. In order to achieve the low temperature conditions during the conversion process and reduce heat leakage at the outlet of the hybrid energy pipeline, the outlet superconducting cable 81 and the second copper wire cable 86 are converted in the hydrogen precooling box 84, and the low temperature hydrogen in the liquid hydrogen active vaporization auxiliary channel 76 is used as a precooling agent.

[0043] Working principle of the invention:

[0044] This invention integrates offshore wind power generation with hydrogen energy based on superconducting technology. It uses the electricity generated by wind power to produce liquid hydrogen on an offshore platform. Then, with the support of cryogenic liquid hydrogen, it realizes the cooling of offshore superconducting wind turbines and the mixed transmission of liquid hydrogen and electricity. This solves problems such as the expansion of offshore wind farms, waste power recovery, and energy storage, while achieving low-loss power transmission.

[0045] This invention proposes an integrated topology structure in which submarine power collection cables and liquid hydrogen cooling pipelines are laid adjacent to each other in parallel. This replaces the independent cooling system of the superconducting fan in the traditional design with a centralized circulating cooling system, reducing the cost of the superconducting fan. At the same time, the liquid hydrogen pipeline is laid along the power collection cable route, which reduces the amount of submarine construction work.

[0046] To reduce energy consumption in hybrid energy pipelines and lower the risk of superconducting pipeline quenching, this invention innovatively utilizes active vaporization technology to design a temperature control section at the end of the hybrid energy pipeline. By creating injection holes in the pipe wall of the liquid hydrogen transport channel, the liquid hydrogen entering the active vaporization auxiliary channel through the injection holes is depressurized to reach its vaporization temperature and releases its latent heat. This allows it to absorb heat input from the external environment through the vacuum insulation layer while simultaneously reducing the temperature of the liquid hydrogen within the liquid hydrogen transport channel, thereby achieving temperature control.

Claims

1. A combined offshore wind power generation and hydrogen-electricity transmission system based on superconducting technology, characterized in that: The system includes an offshore superconducting wind power generation system (1). The electrical energy output by the offshore superconducting wind power generation system (1) is collected to the offshore platform through the submarine power collection cable and the liquid hydrogen cooling pipeline system (2), and converted into stable DC power by the first transformer conversion system (3-1). The offshore liquid hydrogen production system (4) uses a portion of the stable DC power to produce liquid hydrogen. After passing through the pressurization and cooling system (5), a portion of the liquid hydrogen is fed into the liquid hydrogen cooling pipeline of the submarine power collection cable and the liquid hydrogen cooling pipeline system (2) to provide cooling for the superconducting wind turbine. The remaining liquid hydrogen is transported to the superconducting output system (8) through the superconducting access system (6) and the remaining stable DC power through the hybrid energy pipeline (7) using active vaporization temperature control technology. The electricity from the superconducting output system (8) is transmitted to the national grid through the second transformer conversion system (3-2). The liquid hydrogen from the superconducting output system (8) is stored, transported and sold. The offshore liquid hydrogen production system (4) includes a seawater desalination unit (41), a PEM electrolysis water hydrogen production and purification unit (42), and a hydrogen liquefaction unit (43) connected in sequence. Liquid hydrogen is produced using the stable DC power of the offshore platform. After passing through the pressurization and cooling system (5), part of the liquid hydrogen is connected to the liquid hydrogen cooling pipe of the submarine current collection cable and liquid hydrogen cooling pipe system (2) to provide cooling for the superconducting fan (11). The remaining liquid hydrogen is transported to the superconducting output system (8) through the hybrid energy pipe (7) which adopts active vaporization temperature control technology. The submarine power collection cable and liquid hydrogen cooling pipeline system (2) includes two layout schemes: centralized hydrogen production + circulating cooling and distributed hydrogen production + unidirectional cooling. In both schemes, the submarine power collection cable and liquid hydrogen cooling pipeline are arranged adjacent to each other and in parallel. The hybrid energy pipeline (7) using active vaporization temperature control technology is divided into a normal section and a temperature control section along the length of the pipeline. The first section, which accounts for 80%-90% of the total length of the hybrid energy pipeline, is the normal section, which includes a superconducting cable arranged coaxially from the inside to the outside, a liquid hydrogen transport channel (74), and a vacuum insulation layer (75). The second section, which accounts for 10%-20% of the total length of the hybrid energy pipeline, is the temperature control section, which includes a superconducting cable arranged coaxially from the inside to the outside, a liquid hydrogen transport channel (74), a liquid hydrogen active vaporization auxiliary channel (76), and a vacuum insulation layer (75). Among them, the superconducting cable includes a copper skeleton (71), a superconducting layer (72), an electrical insulation layer, and a shielding layer (73) arranged coaxially from the inside to the outside. The cross-sectional dimensions of the superconducting cable and the liquid hydrogen transport channel (74) are the same throughout the entire line. The superconducting cable is always erected in the center of the liquid hydrogen transport channel (74) and is supported by cable pulleys. The liquid hydrogen transport channel of the normal section of the hybrid energy pipeline (74) The outside is a vacuum insulation layer (75). The liquid hydrogen transport channel (74) of the temperature control section of the hybrid energy pipeline is surrounded by a liquid hydrogen active vaporization auxiliary channel (76) and a vacuum insulation layer (75). Multiple injection holes (77) are opened on the pipe wall between the liquid hydrogen transport channel (74) and the liquid hydrogen active vaporization auxiliary channel (76). The injection volume of each injection hole is 1 / 100 of the liquid hydrogen mass flow rate in the liquid hydrogen transport channel (74). After the liquid hydrogen is injected into the liquid hydrogen active vaporization auxiliary channel (76) through the injection hole (77) from the liquid hydrogen transport channel (74), its own pressure decreases and reaches the vaporization temperature. After that, the liquid hydrogen will vaporize during the flow process in the liquid hydrogen active vaporization auxiliary channel (76) and release its own latent heat. It not only absorbs the heat input from the external environment through the vacuum insulation layer (75), but the remaining cold energy also reduces the temperature of the liquid hydrogen in the liquid hydrogen transport channel (74), thereby achieving the effect of temperature control.

2. The combined conveying system according to claim 1, characterized in that: The submarine current collection cable and liquid hydrogen cooling pipeline system (2) adopts a centralized hydrogen production + circulating cooling layout scheme, namely a circulating submarine current collection cable and liquid hydrogen cooling pipeline system, including an offshore platform (21), a submarine current collection cable (22) and a liquid hydrogen cooling pipeline (23), which are connected in sequence to a seawater desalination unit (41), a PEM electrolysis water hydrogen production and purification unit (42) and a hydrogen liquefaction unit (43). Liquid hydrogen is continuously produced on the offshore platform (21). In the pressurization and cooling system (5), the liquid hydrogen booster pump (51) and the helium refrigerator (52) are connected to pressurize and cool the produced liquid hydrogen. Then, the liquid hydrogen is introduced into the liquid hydrogen cooling pipeline (23) to provide cooling for the superconducting fan (11) and is circulated back to the offshore platform (21). If the liquid hydrogen is in the pressurization and cooling system (5) The pressure and supercooling obtained are insufficient to support complete flow and cooling within the liquid hydrogen cooling pipe (23), so a liquid hydrogen booster pump (51) and a helium refrigerator (52) need to be added in the middle. The electrical energy output by the superconducting fan (11) is connected to the submarine power collection cable (22) adjacent to and parallel to the liquid hydrogen cooling pipe (23) via the AC / DC / AC converter (12) and then bidirectionally transmitted to the offshore platform (21). It is then connected to the AC / DC converter (31) to convert it into DC power. Part of the DC power is connected to the power input terminals of the seawater desalination unit (41), the PEM water electrolysis hydrogen production and purification unit (42), and the hydrogen liquefaction unit (43). The remaining DC power is connected to the hybrid energy pipeline (7) using active gasification temperature control technology after the voltage is boosted by the transformer (32).

3. The combined conveying system according to claim 2, characterized in that: In the circulating submarine power collection cable and liquid hydrogen cooling pipeline system (2), the submarine power collection cable (22) and the liquid hydrogen cooling pipeline (23) are arranged adjacent to each other and in parallel. The submarine power collection cable (22) adopts a bidirectional ring structure. Under normal operation, the electrical energy output by the superconducting fan (11) is collected along the submarine power collection cable (22) to the offshore platform (21) nearby. When a fault occurs at any point of the submarine power collection cable (22), the submarine power collection cables (22) on both sides of the fault point can still collect the electrical energy output by the superconducting fan (11) to the offshore platform (21). The liquid hydrogen cooling pipe (23) is parallel to the submarine power collection cable (22). Liquid hydrogen is introduced into the liquid hydrogen cooling pipe (23) from the offshore platform (21). After cooling the superconducting fan (11), it eventually returns to the offshore platform (21). A large offshore superconducting wind farm is designed with one or more offshore platforms (21). Around each offshore platform (21), multiple circulating submarine power collection cables and liquid hydrogen cooling pipe systems (2) need to be set up to achieve cooling of all superconducting fans (11) and collection of electrical energy.

4. The combined conveying system according to claim 1, characterized in that: The submarine power collection cable and liquid hydrogen cooling pipeline system (2) adopts a distributed hydrogen production + unidirectional cooling layout scheme, namely a unidirectional submarine power collection cable and liquid hydrogen cooling pipeline system, including an offshore liquid hydrogen production platform (24), a submarine power collection cable (22), a liquid hydrogen cooling pipeline (23), and an offshore platform (21). The seawater desalination unit (41), the PEM water electrolysis hydrogen production and purification unit (42), and the hydrogen liquefaction unit (43) connected in sequence continuously produce liquid hydrogen on the offshore liquid hydrogen production platform (24). The required electrical energy is provided by a superconducting fan (11) near the offshore liquid hydrogen production platform (24). In the pressurization and cooling system (5), the liquid hydrogen booster pump (51) and the helium refrigerator (52) are connected to pressurize and cool the produced liquid hydrogen, and then pass through the gas. The liquid hydrogen cooling pipe (23) provides cooling for the superconducting fan (11) and is transported to the offshore platform (21) along the liquid hydrogen cooling pipe (23). If the pressure and subcooling obtained by the liquid hydrogen in the pressurization and cooling system (5) are insufficient to support its complete flow and cooling in the liquid hydrogen cooling pipe (23), a liquid hydrogen booster pump (51) and a helium refrigerator (52) need to be added in the middle. The electrical energy output by the other superconducting fans (11) is connected to the submarine power collection cable (22) parallel to the liquid hydrogen cooling pipe (23) and transported unidirectionally to the offshore platform (21). It is converted into DC power by the AC / DC converter (31), and then the voltage is boosted by the transformer (32) before being connected to the hybrid energy pipe (7) which adopts active vaporization temperature control technology.

5. The combined conveying system according to claim 4, characterized in that: In the unidirectional submarine current collector cable and liquid hydrogen cooling pipeline system (2), the submarine current collector cable (22) and the liquid hydrogen cooling pipeline (23) are arranged as adjacent and parallel as possible; the submarine current collector cable (22) adopts a branch-chain structure; the liquid hydrogen cooling pipeline (23) adopts a chain structure, and liquid hydrogen enters the liquid hydrogen cooling pipeline (23) from the offshore liquid production platform (24), and after cooling the superconducting fan (11), it is transported to the offshore platform (21); due to the location limitations of the offshore liquid production platform (24), it is not possible to arrange the liquid hydrogen cooling pipeline (23) in a completely adjacent and parallel manner with the submarine current collector cable (22). One arrangement scheme is to use a branch-chain structure in the submarine current collector cable (22) Find a chain line close to as many superconducting fans (11) as possible and arrange liquid hydrogen cooling pipes (23) along this line; another arrangement scheme is to find a new chain line to arrange liquid hydrogen cooling pipes (23) without considering the existing branch-chain line of the submarine power collection cable (22), but the chain line should overlap with as many submarine power collection cables (22) as possible; a large offshore superconducting wind farm is designed with one or more offshore platforms (21). Around each offshore platform (21), multiple unidirectional submarine power collection cable and liquid hydrogen cooling pipe systems (2) starting from the offshore liquid production platform (24) need to be set up to achieve cooling of the superconducting fans (11) and collection of electrical energy.

6. The combined conveying system according to claim 1, characterized in that: The superconducting access system (6) includes a first copper wire cable (61), a first insulation layer (62), a liquid hydrogen precooling box (63), a liquid hydrogen injection port (64), and an inlet superconducting cable (65), which is used to complete the conversion of the first copper wire cable (61) to the inlet superconducting cable (65) and serve as the injection port for liquid hydrogen in the hybrid energy pipeline; the first copper wire cable (61) and the inlet superconducting cable (65) are converted in the liquid hydrogen precooling box (63), and liquid hydrogen is used as a precooling agent; the liquid hydrogen prepared on the offshore platform is pressurized by the liquid hydrogen booster pump (51) and subcooled by the helium refrigeration unit (52) and then injected into the hybrid energy pipeline (7) using active vaporization temperature control technology through the liquid hydrogen injection port (64).

7. The combined conveying system according to claim 1, characterized in that: The superconducting exit system (8) includes an outlet superconducting cable (81), a hydrogen discharge port (82), a liquid hydrogen discharge port (83), a hydrogen precooling box (84), a second insulation layer (85), and a second copper wire cable (86), which are used to complete the conversion of the outlet superconducting cable (81) to the second copper wire cable (86), and serve as the discharge port of the liquid hydrogen transport channel (74) and the liquid hydrogen active vaporization auxiliary channel (76) in the hybrid energy pipeline; the second copper wire cable (86) and the outlet superconducting cable (81) are converted in the hydrogen precooling box (84), and the low temperature hydrogen in the liquid hydrogen active vaporization auxiliary channel (76) is used as a precooling agent.

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