CN114498756A - Composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation - Google Patents
Composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation Download PDFInfo
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
- H01M8/04858—Electric variables
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/381—Dispersed generators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
- H01M8/04201—Reactant storage and supply, e.g. means for feeding, pipes
- H01M8/04208—Cartridges, cryogenic media or cryogenic reservoirs
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/01—Arrangements for reducing harmonics or ripples
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
- H01M2250/10—Fuel cells in stationary systems, e.g. emergency power source in plant
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/28—The renewable source being wind energy
Abstract
The invention provides a composite superconducting microgrid system for stabilizing offshore wind power fluctuation, offshore wind power is transmitted to a shore through a flexible direct current transmission technology and is merged into a main power grid and water electrolysis hydrogen production equipment, a composite superconducting system formed by combining a superconducting generator, a superconducting booster transformer, a liquid hydrogen-superconducting hybrid seabed alternating current and direct current cable and superconducting energy storage is established in the transmission process, large-capacity electric energy transmission is facilitated, and the cost is reduced. The offshore wind power generation micro-grid system is further established, a wind energy-chemical energy-electric energy hybrid energy storage, utilization and conversion technology is realized, the advantages of cleanness, environmental protection, on-site consumption and the like are achieved, the advantages of superconducting energy storage and fuel cells are effectively combined, the stabilization of offshore wind power generation power fluctuation is achieved, and electric energy with good quality is improved for power users. In the whole process, the composite superconducting system can be cooled better by using the circulation conversion between the hydrogen and the liquid hydrogen and the detection of the flow rate of the liquid hydrogen relay booster station, so that the comprehensive utilization of the hydrogen energy and the composite superconducting system is realized, and the high operation and maintenance cost required by the traditional refrigeration mode is avoided.
Description
Technical Field
The invention belongs to the technical field of superconducting micro-grids, and particularly relates to a composite superconducting micro-grid system applied to offshore wind power and a working method.
Background
In the process of the current global rapid industrial development, the contradiction between energy demand and environmental pollution becomes a problem to be solved urgently, and renewable energy is the key for solving the energy crisis and realizing sustainable development. Wind power generation has become the third most renewable energy power generation mode second to hydroelectric power generation due to the advantages of convenient development, low construction cost and the like, and offshore wind power generation has the advantages of abundant resources, high power generation utilization rate, convenience in power consumption close to an electrical load center and the like, and is becoming a focus of global attention.
The intermittent and random characteristics of wind power generation result in poor quality of generated electric energy. Because the energy storage has the characteristics of bidirectional power characteristics and flexible adjustment capability, the scheme for solving the problems of system instability and the like caused by wind power generation is to configure the energy storage. The energy storage technology can be divided into energy type energy storage (water pumping energy storage, fuel cell and the like) and power type energy storage (superconducting energy storage, super capacitor energy storage and the like), the energy release time of the energy type energy storage system is long, the capacity density is large, but the power response speed is relatively slow and the energy type energy storage system is not suitable for frequent and rapid charging and discharging; the power type energy storage has the advantages of high response speed, high power density and the like. Therefore, the two types of energy storage are combined, and the advantages of the two types of energy storage are respectively gained and compensated, so that the cost can be reduced, and good electric energy quality can be provided.
In a plurality of energy storage technologies, the hydrogen energy storage is used for electrolyzing water to prepare hydrogen by using redundant electric energy generated by wind power generation, the hydrogen is stored, and power is generated by a fuel cell or a gas turbine when needed. The superconducting energy storage technology is characterized in that a magnet coil is constructed by utilizing the zero resistance current-carrying characteristic of a superconducting material below the critical temperature to store electromagnetic energy, power exchange with a power grid is realized through a current transformer, and the superconducting energy storage technology has the advantages of quick response and independent four-quadrant operation.
At present, most offshore wind farms adopt a high-voltage alternating-current power transmission grid-connected mode, but a reactive compensation device needs to be installed to solve the problem of charging current of an alternating-current cable capacitor, so that under the rapid development of high-power electronic devices, flexible direct-current power transmission is widely accepted due to the advantages of low harmonic content, no commutation failure and capability of independently adjusting power. The offshore wind power grid-connected structure based on flexible direct current transmission comprises: the system comprises an offshore wind driven generator, a booster transformer, an alternating current submarine cable, an offshore converter station, a direct current submarine cable, an onshore converter station and a main power grid. The traditional double-fed induction generator and the permanent magnet synchronous generator are difficult to meet the capacity problem of large-scale offshore wind turbine generators, when a high-temperature superconducting generator is adopted, the wind turbine generator is in a direct-drive type, the reliability is improved, the maintenance cost is reduced, in addition, due to the light weight and small size, the design requirements of offshore wind turbine supporting structures and the like are reduced, and the construction cost of wind power plants is reduced. The traditional submarine cable has insufficient current carrying capacity and large electric energy loss, so that the superconducting cable is adopted to replace the traditional submarine power transmission line to meet a high-capacity load center. If the boosting transformer also adopts a superconducting transformer, the weight of the transformer can be effectively reduced, the noise is reduced, and meanwhile, the service life of the transformer is prolonged under the low-temperature environment, so that the construction and maintenance cost is reduced, and the influence on the surrounding marine organisms is small.
Since all superconducting devices need to work in a low-temperature environment, and the liquid hydrogen has the temperature of about 20K and is produced by electrolyzing water, a superconducting cable can be installed inside a liquid hydrogen transmission pipeline, and a magnet in a superconducting transformer and a superconducting energy storage device is soaked in a Dewar filled with the liquid hydrogen. However, in the operation process of the system, the superconducting transformer and the superconducting energy storage device are difficult to avoid thermal disturbance to generate certain heat leakage, and the end part of the liquid hydrogen pipeline of the superconducting submarine cable is connected in a room temperature environment to have heat loss.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide a composite superconducting microgrid system applied to offshore wind power and a working method thereof.
The invention is realized by the following technical scheme:
the invention discloses a composite superconducting microgrid system for stabilizing offshore wind power fluctuation, which is characterized by comprising an offshore superconducting wind turbine generator, a superconducting step-up transformer, a liquid hydrogen-superconducting hybrid submarine alternating current cable, an offshore converter station, a liquid hydrogen relay booster station, a liquid hydrogen-superconducting hybrid submarine direct current cable, an onshore converter station, a main power grid, electrolyzed water hydrogen production equipment, hydrogen liquefaction equipment, a fuel cell and a superconducting energy storage device. The superconducting booster transformer is connected to an offshore converter station through a liquid hydrogen-superconducting hybrid seabed alternating current cable, the offshore converter station is connected with an onshore converter station through a liquid hydrogen-superconducting hybrid seabed direct current cable, the onshore converter station converts electric energy and distributes the converted electric energy to a main power grid and direct-connected electrolyzed water hydrogen production equipment, hydrogen liquefaction equipment is communicated with a gas tank of the electrolyzed water hydrogen production equipment and stores liquid hydrogen in a liquid tank, a superconducting energy storage device is communicated with the gas tank and the liquid tank, a fuel cell is connected with the gas tank, and the superconducting energy storage device and the fuel cell are connected to a direct current bus of the onshore converter station through respective direct current choppers.
Furthermore, the offshore superconducting generator adopts a semi-superconducting generator with a stator winding made of a normal conducting material and a rotor winding made of a superconducting material, liquid helium or liquid neon is used for refrigerating a high-temperature superconductor, refrigerating gas is conveyed into a low-temperature container of a rotor coil through a rotary cold conveying vacuum pipeline with good rotary sealing, and liquid hydrogen is not used for refrigerating the superconducting generator so as to reduce the investment and construction cost of conveying the liquid hydrogen to a higher fan.
Furthermore, the superconducting booster transformer consists of a three-phase laminated iron core, a spiral high-temperature superconducting winding, an annular Dewar only used for cooling the transformer winding, a current lead and a refrigerator for refrigerating the superconducting winding by using liquid hydrogen.
Further, the liquid hydrogen-superconducting hybrid submarine alternating current cable adopts a three-phase concentric alternating current cable, and the structure of each phase of cable from inside to outside is as follows: the low-temperature insulating layer is made of polypropylene laminated paper, three single-phase cables are mutually twisted and arranged in the liquid hydrogen low-temperature Dewar pipeline, and the outside of the Dewar pipeline is waterproof and anticorrosive by adopting an ethylene propylene rubber insulating lead sleeve waterproof layer and a protective layer made of thick steel wire armored polypropylene fibers.
Further, the liquid hydrogen-superconducting hybrid submarine direct current cable adopts a single-pole coaxial cable, and the structure from inside to outside is as follows: the liquid hydrogen internal transmission pipeline, the superconducting layer, the low-temperature insulating layer, the liquid hydrogen external transmission pipeline, the heat insulating layer and the protective layer are made of materials which are consistent with those of the liquid hydrogen-superconducting mixed submarine alternating current cable, the liquid hydrogen external transmission pipeline is a gap between the low-temperature insulating layer and the heat insulating layer, the two liquid hydrogen pipelines adopt single-end countercurrent refrigeration, the heat insulating layer is made of coaxial double-layer stainless steel corrugated pipes, the space between the two layers is vacuumized, and multiple layers of radiation-proof metal foils are embedded between the two layers, so that the superconducting layer is always in a low-temperature environment to maintain a superconducting state.
Preferably, alternating current output by the offshore superconducting wind turbine generator is boosted by a superconducting booster transformer and then transmitted to an alternating current bus of an offshore converter station through a liquid hydrogen-superconducting hybrid seabed alternating current cable, the offshore converter station converts the alternating current into direct current and transmits the direct current to a direct current bus of an onshore converter station through a liquid hydrogen-superconducting hybrid seabed direct current cable, and the onshore converter station inverts the direct current into the alternating current to be connected to a main power grid and water electrolysis hydrogen production equipment, so that the centralized grid connection of the offshore wind turbine generator based on flexible direct current transmission is realized.
Further, hydrogen of the fuel cell is derived from hydrogen stored in a gas tank after hydrogen is produced by electrolyzing water, and the air inflow of the hydrogen in the cell and the first direct current chopper are controlled according to the load and the electrical characteristics detected by the main power grid, so that the generated power is adjusted.
Furthermore, the superconducting energy storage magnet in the superconducting energy storage device is in a superconducting state in a Dewar filled with liquid hydrogen, and is charged and discharged through a second direct current chopper.
Preferably, the electric energy generated by offshore wind power is produced in electrolytic water hydrogen production equipment and stored in a gas tank, part of the hydrogen in the gas tank is used for power generation of a fuel cell, part of the hydrogen is liquefied into liquid hydrogen by hydrogen liquefaction equipment and stored in a liquid tank, part of the liquid hydrogen in the liquid tank enters a superconducting energy storage device to cool a superconducting magnet, and part of the liquid hydrogen enters a liquid hydrogen-superconducting hybrid seabed alternating current and direct current cable and a superconducting step-up transformer, so that the composite superconducting system is in a low-temperature environment with the liquid hydrogen, and the raw materials of the fuel cell are supplemented.
Preferably, the superconducting energy storage device and the fuel cell control respective choppers to charge or discharge according to electrical characteristics on a direct current bus, so that power fluctuation stabilization of offshore wind power generation is realized.
Preferably, the liquid tank is connected with a liquid hydrogen transmission pipeline in the liquid hydrogen-superconducting hybrid submarine AC/DC cable through a liquid hydrogen pump and is finally connected to the superconducting booster transformer, and a controller on the liquid hydrogen relay booster station judges whether the liquid hydrogen pump is needed to supplement insufficient liquid hydrogen in the pipeline or not by monitoring the flow rate of the liquid hydrogen in the liquid hydrogen transmission pipeline, so that the liquid hydrogen-superconducting submarine AC/DC cable is prevented from being quenched due to the insufficient liquid hydrogen.
Preferably, the liquid hydrogen in the liquid tank enters the dewar through the liquid inlet pipe to cool the superconducting energy storage device, and the heat generated by the superconducting energy storage magnet in the superconducting energy storage device in the operation process gasifies the liquid hydrogen in the dewar to generate hydrogen, and the hydrogen enters the gas tank through the gas exhaust pipe.
Preferably, the liquid level of the liquid hydrogen in the annular Dewar of the superconducting booster transformer is changed when the transformer works, when the liquid level is reduced to a certain degree, the liquid hydrogen pump of the refrigerator sends the liquid hydrogen into the Dewar from the liquid inlet pipe of the transformer, and meanwhile, the gasified hydrogen enters the liquid hydrogen pump through the exhaust pipe of the transformer and is changed into the liquid hydrogen to be continuously recycled after passing through the heat exchanger, so that the utilization rate of hydrogen energy is improved.
Preferably, the liquid level in a dewar of the superconducting energy storage device changes in the operation process of the superconducting energy storage device, the intelligent control switch on the liquid inlet pipe controls the opening and closing of the liquid inlet pipe according to a signal sensed by the liquid level sensor in the dewar, and the intelligent control switch on the exhaust pipe controls the opening and closing of the exhaust pipe according to the gas pressure sensed by the pressure sensor in the dewar, so that the liquid level in the dewar always passes through the superconducting energy storage magnet, a low-temperature environment is provided for the superconducting energy storage device by utilizing the gas-liquid state conversion of hydrogen, and the mixed utilization of the liquid hydrogen and the superconducting energy storage is realized.
The invention also aims to provide specific steps of the composite superconducting microgrid system for stabilizing offshore wind power fluctuation, which comprises the following steps:
s1, generating power, converting wind energy into electric energy by the offshore superconducting generator set, boosting the electric energy by the superconducting booster transformer, and then conveying the electric energy to the offshore converter station by the liquid hydrogen-superconducting hybrid submarine alternating current cable to realize conversion of the offshore wind energy and the electric energy;
s2, converting current, wherein the offshore converter station adopts flexible direct current transmission to convert three-phase alternating current into direct current, the direct current is transmitted to an onshore converter station through a liquid hydrogen-superconducting mixed seabed direct current cable, the onshore converter station inverts the direct current into alternating current, the power consumption requirements of the water electrolysis hydrogen production equipment and the superconducting energy storage device are met preferentially, and surplus electric energy is transmitted to a main power grid to realize reasonable distribution of the electric energy;
s3, hydrogen production and storage are performed, water electrolysis hydrogen production equipment performs water electrolysis hydrogen production after receiving electric energy sent by an onshore converter, hydrogen is stored in a gas tank, hydrogen liquefaction equipment converts the hydrogen in the gas tank into liquid hydrogen, and the liquid hydrogen is stored in a liquid tank, so that conversion of the electric energy and the hydrogen and the liquid hydrogen is realized;
s4, power is stabilized, hydrogen in a gas tank can be used as a raw material of a fuel cell, liquid hydrogen enters a Dewar of a superconducting energy storage device along a liquid inlet pipe, the liquid hydrogen overflows a superconducting energy storage magnet to realize immersion refrigeration, and the fuel cell and the superconducting energy storage device judge and control the charging and discharging of respective direct current choppers through the electrical characteristics on a connected direct current bus, so that the stabilization of the power fluctuation of offshore wind power generation is realized;
in S2, a liquid hydrogen relay booster station is added because the liquid hydrogen-superconducting hybrid submarine direct current cable has a long conveying distance and the liquid hydrogen pump may not be capable of completely conveying liquid hydrogen to the superconducting booster transformer, and when the flow rate of the liquid hydrogen in the liquid hydrogen conveying pipeline is monitored to be lower than a lower threshold value, the liquid hydrogen pump on the liquid hydrogen relay booster station is started to supplement the insufficient liquid hydrogen in the pipeline;
in S2, when the liquid level of a Dewar in a refrigerator of the superconducting booster transformer is detected to be reduced to a lowest set value, a liquid inlet valve is opened to make liquid hydrogen in a liquid tank supplemented, and when the liquid hydrogen in the liquid tank of the transformer is insufficient, a liquid hydrogen pump on a liquid hydrogen relay booster station supplements the liquid hydrogen;
in S3, the hydrogen in the gas tank preferentially meets the requirements of hydrogen liquefaction equipment, the surplus hydrogen can be used for a fuel cell, and the liquid hydrogen in the liquid tank preferentially meets the requirements of a superconducting energy storage device, a liquid hydrogen-superconducting hybrid submarine alternating current-direct current cable and a superconducting step-up transformer so as to ensure that the superconducting energy storage device, the liquid hydrogen-superconducting hybrid submarine alternating current-direct current cable and the superconducting step-up transformer are in a low-temperature environment for a long time;
in S4, when the liquid level of the liquid hydrogen in the Dewar is lower than the minimum threshold value, the liquid level sensor opens the intelligent control switch on the liquid inlet pipe by the sensed signal to let the liquid hydrogen enter the superconducting energy storage device, the liquid hydrogen is easy to be gasified by the heat emitted by the superconducting energy storage device when running, and when the pressure of the hydrogen in the Dewar is higher than the maximum threshold value, the intelligent control switch on the exhaust pipe controls the intelligent switch of the exhaust pipe to open according to the gas pressure sensed by the pressure sensor in the Dewar to let the hydrogen enter the gas tank;
in S4, when the dc choppers of the fuel cell and the superconducting energy storage device are controlled, the high-frequency component of the power fluctuation is absorbed by the superconducting energy storage device and the low-frequency component is absorbed by the fuel cell by using a filter.
Compared with the prior art, the invention has the following beneficial effects:
1) the invention establishes a composite superconducting system formed by combining a superconducting generator, a superconducting booster transformer, a superconducting cable and superconducting energy storage by utilizing the characteristics of approximate zero resistance and zero loss of superconductivity, facilitates large-capacity electric energy transmission and reduces the cost, simultaneously maintains the working environment temperature of the superconducting seabed alternating current and direct current cable arranged in a liquid hydrogen pipeline by utilizing low-temperature and environment-friendly liquid hydrogen, and controls a liquid hydrogen pump in a liquid hydrogen relay booster station by detecting the flow velocity in the liquid hydrogen transmission pipeline so as to effectively solve the problem of heat leakage of the superconducting booster transformer and the superconducting seabed cable.
2) The invention establishes a micro-grid system of offshore wind power, a composite superconducting system, hydrogen storage and a fuel cell, realizes the storage, utilization and conversion technology of wind energy-chemical energy-electric energy mixed energy, has the advantages of cleanness, environmental protection, local consumption and the like, effectively utilizes the characteristics of millisecond-level response speed, extremely high conversion efficiency, nearly infinite charge-discharge cycle times and high power density of superconducting energy storage, simultaneously utilizes the characteristics of long discharge time, high energy density and no pollution of the fuel cell, carries out high-low frequency filtering on the power of offshore wind power generation, and then controls the superconducting energy storage and the charge-discharge of the fuel cell, thereby realizing the stabilization of power fluctuation and improving the electric energy with good quality for power users.
3) The composite superconducting system is cooled by using the cyclic conversion between the hydrogen and the liquid hydrogen, so that the comprehensive utilization of the hydrogen energy and the composite superconducting system is realized, and the high operation and maintenance cost required by the traditional refrigeration mode is avoided.
Drawings
Fig. 1 is a schematic structural diagram of a composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation according to the invention;
FIG. 2 is a schematic diagram of a superconducting step-up transformer according to the present invention;
FIG. 3 is a schematic structural view of a liquid hydrogen-superconducting hybrid submarine AC cable according to the present invention;
fig. 4 is a schematic structural view of a liquid hydrogen-superconducting hybrid submarine direct current cable according to the present invention;
fig. 5 is a schematic structural diagram of a superconducting energy storage device according to the present invention.
The reference numbers in the figures are: 1-an offshore superconducting wind turbine; 2-a superconducting step-up transformer; 201-liquid hydrogen tank; 202-a liquid outlet valve; 203-transformer refrigerator dewar; 204-transformer liquid hydrogen pump; 205-a heat exchanger; 206-transformer exhaust; 207-transformer feed liquor pipe; 208-current leads; 209-transformer winding; 210-a transformer toroidal dewar; 211-transformer core; 212-transformer chiller; 3-liquid hydrogen-superconducting hybrid submarine alternating current cable; 301-liquid hydrogen transport pipeline; 302-a superconducting layer; 303-low temperature insulating layer; 304-a superconducting shielding layer; 305-liquid hydrogen cryogenic dewar pipe; 306-a waterproof layer; 307-a protective layer; 4-liquid hydrogen relay booster station; 5-an offshore converter station; 6-liquid hydrogen-superconducting hybrid submarine direct current cable; 601-liquid hydrogen internal transmission pipeline; 602-a superconducting layer; 603-low temperature insulating layer; 604-liquid hydrogen external transport pipeline; 605-a thermal insulation layer; 606-a protective layer; 7-an onshore converter station; 8-main grid; 9-a superconducting energy storage device; 901-a superconducting energy storage device dewar; 902-superconducting energy storage magnet; 903-intelligent control switch for liquid inlet pipe; 904-exhaust pipe intelligent control switch; 10-a fuel cell; 11-water electrolysis hydrogen production equipment; 12-a gas tank; 13-a hydrogen liquefaction plant; 14-a liquid tank; 15-a first dc chopper; 16-a second dc chopper; 17-a direct current bus; 18-ac bus; 19-a liquid inlet pipe; 20-an exhaust pipe; 21-liquid hydrogen pump.
Detailed Description
In order to make the implementation objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be further described below with reference to the accompanying drawings in the embodiments of the present invention. In the drawings, the same reference numerals denote apparatuses or devices of the same or similar functions throughout the drawings. The described embodiments are illustrative of some of the present invention, and the described aspects and words of orientation are not to be considered as limiting, but rather as specifying and not limiting the invention.
In a broad embodiment of the invention, a composite superconducting microgrid system applied to stabilize offshore wind power fluctuation is shown in figure 1, and is characterized by comprising an offshore superconducting generator set 1, a superconducting step-up transformer 2, a liquid hydrogen-superconducting hybrid submarine alternating current cable 3, an offshore converter station 4, a liquid hydrogen relay booster station 5, a liquid hydrogen-superconducting hybrid submarine direct current cable 6, an onshore converter station 7, a main power grid 8, a superconducting energy storage device 9, a fuel cell 10, an electrolytic water hydrogen production device 11 and a hydrogen liquefaction device 13. The offshore superconducting generator set 1, the superconducting step-up transformer 2, the liquid hydrogen-superconducting hybrid submarine alternating current and direct current cables 3 and 6 and the superconducting energy storage device 9 form a composite superconducting system.
Alternating current output by the offshore superconducting wind turbine generator 1 is boosted by a superconducting booster transformer 2 and then converged on an alternating current bus 18, the alternating current is transmitted to an offshore converter station 4 through a liquid hydrogen-superconducting mixed seabed alternating current cable 3, the offshore converter station 4 converts the alternating current into direct current, the direct current is transmitted to a direct current bus 17 of an onshore converter station 7 through a liquid hydrogen-superconducting mixed seabed direct current cable 6, the onshore converter station 7 inverts the direct current into the alternating current, and the alternating current is connected into a main power grid 8 and water electrolysis hydrogen production equipment 11, so that offshore wind power grid connection based on flexible direct current transmission is realized; the superconducting energy storage device 9 and the fuel cell 10 control the respective direct current choppers 15 and 16 to charge and discharge according to the electrical characteristics on the direct current bus 17, so that the power fluctuation of the offshore wind power generation device is stabilized.
Electric energy generated by offshore wind power is produced in electrolytic water hydrogen production equipment 11 and stored in a gas tank 12, part of hydrogen in the gas tank 12 is used for power generation of a fuel cell 10, and the other part of the hydrogen is liquefied into liquid hydrogen through hydrogen liquefaction equipment 13 and stored in a liquid tank 14, part of the liquid hydrogen in the liquid tank 14 enters a superconducting energy storage device 9 to cool a superconducting energy storage magnet 902, and the other part of the liquid hydrogen enters liquid hydrogen-superconducting hybrid submarine alternating current and direct current cables 3 and 6; the hydrogen raw material of the fuel cell 10 is derived from hydrogen stored in the gas tank 12 after hydrogen is produced by electrolyzing water, and the amount of intake of hydrogen in the cell and the first dc chopper 15 are controlled according to the load and the electrical characteristics detected by the main power grid, thereby adjusting the generated power.
The structure of the superconducting booster transformer 2 is shown in figure 2, and the superconducting booster transformer is composed of a current lead 208, a spiral high-temperature superconducting winding 209, an annular Dewar 210 only cooling the transformer winding, a three-phase laminated iron core 211 and a refrigerator 212 refrigerating the superconducting winding by liquid hydrogen, wherein the liquid level of the liquid hydrogen in the annular Dewar 210 changes when the transformer works, when the liquid level drops to a certain degree, the liquid hydrogen is sent into the Dewar by a liquid inlet pipe 207 by a liquid hydrogen pump 204 of the refrigerator, and simultaneously the gasified hydrogen enters a heat exchanger 205 through an exhaust pipe 206 and then is changed into the liquid hydrogen for continuous recycling; when the liquid hydrogen in the Dewar 203 of the transformer refrigerator drops to the lowest set value, the liquid outlet valve 202 is opened to supplement the liquid hydrogen in the Dewar; when the liquid hydrogen in the transformer liquid tank 201 is reduced to the lowest set value, a liquid inlet valve on the tank is opened and the liquid hydrogen is supplemented through a liquid hydrogen pump on the liquid hydrogen relay booster station.
The liquid hydrogen-superconducting hybrid submarine alternating current cable structure is as shown in the attached figure 3, a three-phase concentric alternating current cable is adopted, and the structure of each phase of cable from inside to outside is as follows: the liquid hydrogen transmission pipeline 301 is made of a stainless steel corrugated pipe, the superconducting layer 302 and the superconducting shielding layer 304 are both made of second-generation superconducting tapes YBCO, the low-temperature insulating layer 303 is made of polypropylene laminated paper, three single-phase cables are mutually twisted and arranged in the liquid hydrogen low-temperature Dewar pipe 305, and the outside of the Dewar pipe is waterproof and anticorrosive by adopting an ethylene propylene rubber insulating lead sheath waterproof layer 306 and a protective layer 307 made of thick steel wire armored polypropylene fibers.
The structure of the liquid hydrogen-superconducting hybrid submarine direct current cable is as shown in figure 4, a single-pole coaxial cable is adopted, and the structure from inside to outside is as follows: the liquid hydrogen internal transmission pipeline 601, the superconducting layer 602, the low-temperature insulating layer 603, the liquid hydrogen external transmission pipeline 604, the heat insulating layer 605 and the protective layer 606, the materials used for the liquid hydrogen internal transmission pipeline 601, the superconducting layer 602, the low-temperature heat insulating layer 603 and the protective layer 606 are all the same as those of the liquid hydrogen-superconducting hybrid submarine alternating current cable 3, the liquid hydrogen external transmission pipeline 604 is a gap between the low-temperature insulating layer 603 and the heat insulating layer 605, the two liquid hydrogen pipelines adopt single-end countercurrent refrigeration, the low-temperature heat insulating layer is made of coaxial double-layer stainless steel corrugated pipes, the space between the two layers is vacuumized, and a plurality of layers of radiation-proof metal foils are embedded.
The liquid tank 14 is connected with the liquid hydrogen-superconducting hybrid submarine direct current cable 6, the liquid hydrogen relay booster station 5 and the liquid hydrogen-superconducting hybrid submarine alternating current cable 3 in sequence through a liquid hydrogen pump 21 and is finally connected to the liquid tank 201 at the superconducting booster transformer 2, and a controller on the liquid hydrogen relay booster station 5 judges whether the liquid hydrogen pump is needed to supplement the insufficient liquid hydrogen in the pipeline and the superconducting transformer liquid hydrogen tank 201 by monitoring the flow rate of the liquid hydrogen in the liquid hydrogen transmission pipeline in the submarine cable.
The structure of the superconducting energy storage device is shown in fig. 5, liquid hydrogen in a liquid tank 14 enters a dewar 901 through a liquid inlet pipe 19 to cool the superconducting energy storage device, so that the superconducting energy storage magnet 902 is in a superconducting state, but heat generated by the superconducting energy storage magnet 902 in the operation process can gasify liquid hydrogen in the dewar to generate hydrogen, and the hydrogen enters the gas tank through an exhaust pipe 20, so that the liquid level and the pressure in the dewar also change, an intelligent control switch 903 on the liquid inlet pipe 19 controls the opening and closing of the liquid inlet pipe according to a signal sensed by a liquid level sensor in the dewar, and an intelligent control switch 904 on the exhaust pipe 20 controls the opening and closing of the exhaust pipe according to the gas pressure sensed by the pressure sensor in the dewar, so that the liquid level in the dewar 901 always sinks over the superconducting energy storage magnet 902.
The invention also provides the concrete steps of the composite superconducting microgrid system for stabilizing offshore wind power fluctuation, which comprises the following steps:
s1, generating power, converting wind energy into electric energy by the offshore superconducting generator set 1, boosting the electric energy by the superconducting booster transformer 2, and then conveying the electric energy to the offshore converter station 4 by the liquid hydrogen-superconducting hybrid submarine alternating current cable 3, so as to realize conversion of the offshore wind energy and the electric energy;
s2, converting current, wherein the offshore converter station 4 converts three-phase alternating current into direct current by adopting flexible direct current transmission, the direct current is transmitted to an onshore converter station through a liquid hydrogen-superconducting mixed seabed direct current cable 6, the onshore converter station 7 inverts the direct current into alternating current, the power consumption requirements of the superconducting energy storage device 9 and the electrolyzed water hydrogen production equipment 11 are met preferentially, and surplus electric energy is transmitted to the main power grid 8, so that reasonable distribution of the electric energy is realized;
s3, hydrogen production and storage are performed, the water electrolysis hydrogen production equipment 11 performs water electrolysis hydrogen production after receiving electric energy sent by the onshore converter, hydrogen is stored in the gas tank 12, the hydrogen liquefaction equipment 13 converts the hydrogen in the gas tank into liquid hydrogen, and the liquid hydrogen is stored in the liquid tank 14, so that the conversion of the electric energy and the hydrogen energy and the conversion of the hydrogen and the liquid hydrogen are realized;
s4, power is stabilized, hydrogen in a gas tank can be used as a raw material of the fuel cell 10, liquid hydrogen enters a Dewar 901 of the superconducting energy storage device 9 along a liquid inlet pipe 19, the liquid hydrogen overflows a superconducting energy storage magnet 902 of the superconducting energy storage device to realize immersion refrigeration, the superconducting energy storage device 9 and the fuel cell 10 judge and control charging and discharging of respective direct current choppers through electrical characteristics on a connected direct current bus, and further power fluctuation of offshore wind power generation is stabilized;
in S2, since the liquid hydrogen-superconducting hybrid submarine dc cable 6 has a long delivery distance, and the liquid hydrogen pump 21 may not be able to completely deliver liquid hydrogen to the superconducting booster transformer 2, the liquid hydrogen relay booster station 5 is added, and when it is detected that the flow rate of liquid hydrogen in the liquid hydrogen delivery pipeline is lower than the lower threshold, the liquid hydrogen pump on the liquid hydrogen relay booster station 5 is started to supplement the insufficient liquid hydrogen in the pipeline;
in S3, the hydrogen in the tank 12 preferentially meets the requirement of the hydrogen liquefaction equipment 13, the surplus hydrogen can be used for the fuel cell 10, and the liquid hydrogen in the tank 14 preferentially meets the requirements of the superconducting energy storage device 9, the liquid hydrogen-superconducting hybrid submarine ac/dc cables 3 and 6 and the superconducting step-up transformer 2, so as to ensure that the superconducting energy storage device, the liquid hydrogen-superconducting hybrid submarine ac/dc cables 3 and 6 and the superconducting step-up transformer 2 are in a low-temperature environment for a long time;
in S4, when the liquid level of the liquid hydrogen in the dewar 901 is lower than the minimum threshold, the liquid level sensor will sense a signal to open the intelligent control switch 903 on the liquid inlet pipe 19 to let the liquid hydrogen enter the superconducting energy storage device 9, the liquid hydrogen is easily gasified by the heat emitted by the superconducting energy storage device when operating, and when the pressure of the hydrogen in the dewar 901 is higher than the maximum threshold, the intelligent control switch 904 on the exhaust pipe 20 controls the exhaust pipe to open only the switch according to the gas pressure sensed by the pressure sensor in the dewar 901 to let the hydrogen enter the gas tank;
in S4, when the dc choppers of the superconducting energy storage device 9 and the fuel cell 10 are controlled, the high-frequency component of the power fluctuation is absorbed by the superconducting energy storage device and the low-frequency component is absorbed by the fuel cell by using a filter.
Finally, it should be noted that the above embodiments are only preferred technical solutions of the present invention, and equivalent changes of the system described in the present invention are included in the protection scope of the present invention. Persons skilled in the art to which the invention pertains may make further modifications and improvements with reference to the described embodiments or may make equivalent substitutions on parts of technical features or any combination thereof, as long as the essence of the corresponding technical solution does not depart from the technical spirit and scope of the present invention, and all other embodiments obtained without making creative efforts fall within the protection scope of the present invention.
Claims (9)
1. The composite superconducting microgrid system is used for stabilizing offshore wind power fluctuation and is characterized by comprising an offshore superconducting wind turbine generator set (1), a superconducting step-up transformer (2), a liquid hydrogen-superconducting hybrid submarine alternating current cable (3), a liquid hydrogen relay booster station (4), an offshore converter station (5), a liquid hydrogen-superconducting hybrid submarine direct current cable (6), an onshore converter station (7), a main power grid (8), a superconducting energy storage device (9), a fuel cell (10), water electrolysis hydrogen production equipment (11) and hydrogen liquefaction equipment (13). The superconducting booster transformer (2) is connected to an offshore converter station (5) through a liquid hydrogen-superconducting hybrid submarine alternating current cable (3), the offshore converter station (5) is connected with an onshore converter station (7) through a liquid hydrogen-superconducting hybrid submarine direct current cable (6), the onshore converter station (7) converts electric energy and distributes the converted electric energy to a main power grid (8) and directly-connected electrolyzed water hydrogen production equipment (11), hydrogen liquefaction equipment (13) is communicated with a gas tank (12) of the electrolyzed water hydrogen production equipment and stores the liquid hydrogen in a liquid tank (14), a superconducting energy storage device (9) is communicated with the gas tank (12) and the liquid tank (14), a fuel cell (10) is connected with the gas tank (12), and the superconducting energy storage device (9) and the fuel cell (10) are connected to a direct current bus (17) of the onshore converter station (7) through respective direct current choppers.
2. The composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation according to claim 1, characterized in that alternating current output by the offshore superconducting wind turbine (1) is boosted by a superconducting booster transformer (2) and then converged on an alternating current bus (18), and then is transmitted to an offshore converter station (5) through a liquid hydrogen-superconducting hybrid submarine alternating current cable (3), the offshore converter station (5) converts the alternating current into direct current, and transmits the direct current to a direct current bus (17) of an onshore converter station through a liquid hydrogen-superconducting hybrid submarine direct current cable (6), and the onshore converter station (7) inverts the direct current into alternating current to be connected to a main power grid (8) and an electrolyzed water hydrogen production device (11); wherein the content of the first and second substances,
the offshore superconducting generator (1) adopts a semi-superconducting generator with a stator winding made of a normal conducting material and a rotor winding made of a superconducting material, liquid helium or liquid neon is used for refrigerating a high-temperature superconductor, and refrigerating gas is conveyed into a low-temperature container of a rotor coil through a rotary cold conveying vacuum pipeline with good rotary sealing;
the superconducting booster transformer (2) consists of a current lead (208), a spiral high-temperature superconducting winding (209), an annular Dewar (210) only used for cooling the transformer winding, a three-phase laminated iron core (211) and a refrigerator (212) for refrigerating the superconducting winding by using liquid hydrogen;
the liquid hydrogen-superconducting hybrid submarine alternating current cable (3) adopts a three-phase concentric alternating current cable, and the structure of each phase of cable from inside to outside is as follows: the liquid hydrogen transmission pipeline (301) is made of a stainless steel corrugated pipe, the superconducting layer (302), the low-temperature insulating layer (303) and the superconducting shielding layer (304) are both made of second-generation superconducting tapes YBCO, and the low-temperature insulating layer (303) is made of polypropylene laminated paper; three single-phase cables are twisted with each other and are arranged in a liquid hydrogen low-temperature Dewar pipe (305), and an ethylene propylene rubber insulating lead sheath waterproof layer (306) and a thick steel wire armored polypropylene fiber are adopted outside the Dewar pipe as a protective layer (307) for water resistance and corrosion resistance;
the liquid hydrogen-superconducting hybrid submarine direct current cable (6) adopts a single-pole coaxial cable, and the structure from inside to outside is as follows: the liquid hydrogen internal transmission pipeline (601), the superconducting layer (602), the low-temperature insulating layer (603), the liquid hydrogen external transmission pipeline (604), the heat insulating layer (605) and the protective layer (606), wherein the materials of the liquid hydrogen internal transmission pipeline (601), the superconducting layer (602), the low-temperature heat insulating layer (603) and the protective layer (606) are all the same as those of a liquid hydrogen-superconducting mixed submarine alternating current cable, the liquid hydrogen external transmission pipeline (604) is a gap between the electric insulating layer and the heat insulating layer, the two liquid hydrogen pipelines adopt single-end countercurrent refrigeration, the heat insulating layer (605) is made of coaxial double-layer stainless steel corrugated pipes, the space between the two layers is vacuumized, and a plurality of layers of radiation-proof metal foils are embedded.
3. The composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation according to claim 1, characterized in that electric energy generated by offshore wind power is produced in an electrolytic water hydrogen production device (11) and stored in a gas tank (12), a part of hydrogen in the gas tank is used for power generation of a fuel cell (10), a part of hydrogen is liquefied into liquid hydrogen by a hydrogen liquefaction device (13) and stored in a liquid tank (14), a part of the liquid hydrogen in the liquid tank enters a superconducting energy storage device (9) to cool a superconducting magnet, and a part of the liquid hydrogen enters a liquid hydrogen-superconducting hybrid seabed alternating current and direct current cable; wherein the content of the first and second substances,
the hydrogen of the fuel cell (10) is derived from the hydrogen stored in the gas tank (12) after the hydrogen is produced by electrolyzing water, and the air intake quantity of the hydrogen in the cell and the first direct current chopper (15) are controlled according to the load and the electrical characteristics detected by the main power grid (8), so that the generated power is adjusted;
the superconducting energy storage magnet (902) in the superconducting energy storage device (9) is in a superconducting state in a Dewar (901) filled with liquid hydrogen, and is charged and discharged through a second direct current chopper (16).
4. The composite superconducting microgrid system for stabilizing offshore wind power fluctuation according to claims 1 and 3, characterized in that the superconducting energy storage device (9) and the fuel cell (10) control respective choppers to charge or discharge according to electrical characteristics on the direct current bus (17), so as to stabilize power fluctuation of the offshore wind power generation device.
5. The composite superconducting microgrid system for stabilizing offshore wind power fluctuation according to claim 3, characterized in that the liquid tank (14) is connected with a liquid hydrogen transmission pipeline in a liquid hydrogen-superconducting hybrid submarine alternating current and direct current cable through a liquid hydrogen pump (21) and finally connected to the superconducting step-up transformer (2), and a controller on the liquid hydrogen relay booster station (4) judges whether the liquid hydrogen pump (21) is needed to supplement the insufficient liquid hydrogen in the pipeline by monitoring the flow rate of the liquid hydrogen in the liquid hydrogen transmission pipeline.
6. The composite superconducting microgrid system for stabilizing offshore wind power fluctuation according to claim 3, characterized in that liquid hydrogen in the liquid tank (14) enters a Dewar (901) through a liquid inlet pipe (19) to cool the superconducting energy storage device. And the heat generated by the superconducting energy storage magnet (902) in the superconducting energy storage device in the operation process gasifies the liquid hydrogen in the Dewar to generate hydrogen, and the hydrogen enters the gas tank (12) through the exhaust pipe (20).
7. The composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation according to claims 2 and 5, characterized in that the liquid level of liquid hydrogen in an annular Dewar (210) of the superconducting step-up transformer is changed when the transformer works, when the liquid level drops to a certain degree, the liquid hydrogen pump (204) of a refrigerator (212) sends the liquid hydrogen into the Dewar from a liquid inlet pipe (207), and simultaneously the gasified hydrogen enters the liquid hydrogen pump through an exhaust pipe (206) and is changed into liquid hydrogen to be continuously recycled after passing through a heat exchanger (205).
8. The composite superconducting microgrid system applied to stabilizing offshore wind power fluctuation according to claim 6 is characterized in that the liquid level in a Dewar (901) of the superconducting energy storage device changes in the operation process of the superconducting energy storage device (9), an intelligent control switch (903) on a liquid inlet pipe (19) controls the opening and closing of the liquid inlet pipe according to signals sensed by a liquid level sensor in the Dewar, and an intelligent control switch (904) on an exhaust pipe (20) controls the opening and closing of the exhaust pipe according to gas pressure sensed by a pressure sensor in the Dewar, so that the liquid level in the Dewar always sinks past the superconducting energy storage magnet (902).
9. The composite superconducting microgrid system for stabilizing offshore wind power fluctuation according to claims 1 to 8 is characterized by comprising the following steps:
s1, power generation is carried out, wind energy is converted into electric energy by the offshore superconducting generator set (1), the electric energy is boosted by the superconducting booster transformer (2) and then is transmitted to the offshore converter station (5) through the liquid hydrogen-superconducting hybrid submarine alternating current cable (3), and conversion of the offshore wind energy and the electric energy is achieved;
s2, current transformation is carried out, the offshore converter station (5) adopts flexible direct current transmission to convert three-phase alternating current into direct current, the direct current is transmitted to an onshore converter station (7) through a liquid hydrogen-superconducting mixed seabed direct current cable (6), the onshore converter station (7) inverts the direct current into alternating current, the power consumption requirements of the electrolyzed water hydrogen production equipment (11) and the superconducting energy storage device (9) are met preferentially, and surplus electric energy is transmitted to a main power grid (8), so that reasonable distribution of the electric energy is realized;
s3, hydrogen production and storage are performed, after the water electrolysis hydrogen production equipment (11) receives electric energy sent by the onshore converter (7), water electrolysis hydrogen production is performed, hydrogen is stored in the gas tank (12), the hydrogen liquefaction equipment (13) converts the hydrogen in the gas tank into liquid hydrogen, and the liquid hydrogen is stored in the liquid tank (14), so that conversion of the electric energy and the hydrogen energy as well as the hydrogen and the liquid hydrogen is realized;
s4, power is stabilized, hydrogen in a gas tank (12) can be used as a raw material of a fuel cell (10), liquid hydrogen enters a Dewar of a superconducting energy storage device (9) along a liquid inlet pipe (19), the liquid hydrogen overflows a superconducting energy storage magnet (902) of the superconducting energy storage device to realize immersion refrigeration, and the fuel cell (10) and the superconducting energy storage device (9) judge and control charging and discharging of respective direct current choppers through electrical characteristics on a connected direct current bus (17) so as to realize stabilization of power fluctuation of offshore wind power generation;
in S2, because the liquid hydrogen-superconducting hybrid submarine direct current cable (6) is long in conveying distance, the liquid hydrogen pump (21) may not be capable of completely conveying liquid hydrogen to the superconducting booster transformer (2), so that a liquid hydrogen relay booster station (4) is added, and when the flow rate of the liquid hydrogen in the liquid hydrogen conveying pipeline is monitored to be lower than a lower threshold value, the liquid hydrogen pump on the liquid hydrogen relay booster station is started to supplement insufficient liquid hydrogen in the pipeline;
in S2, when the liquid level of a Dewar (203) in a refrigerator of the superconducting booster transformer (2) is detected to be reduced to a lowest set value, a liquid inlet valve (202) is opened to make liquid hydrogen in a liquid tank (201) supplemented, and when the liquid hydrogen in the liquid tank (201) is insufficient, a liquid hydrogen pump on a liquid hydrogen relay booster station (4) supplements the liquid hydrogen;
in S3, the hydrogen in the gas tank (12) meets the requirements of the hydrogen liquefaction equipment (13) preferentially, the surplus hydrogen can be used for the fuel cell (10), and the liquid hydrogen in the liquid tank (14) meets the requirements of the superconducting energy storage device (9), the liquid hydrogen-superconducting hybrid submarine alternating current-direct current cable (6) and the superconducting booster transformer (2) preferentially so as to ensure that the superconducting energy storage device, the liquid hydrogen-superconducting hybrid submarine alternating current-direct current cable and the superconducting booster transformer are in a low-temperature environment for a long time;
in S4, when the liquid level of liquid hydrogen in a Dewar (901) is lower than a minimum threshold value, a liquid level sensor opens an intelligent control switch (903) on a liquid inlet pipe (19) by a sensed signal to allow the liquid hydrogen to enter a superconducting energy storage device (9), the liquid hydrogen is easily gasified by heat emitted by the superconducting energy storage device (9) during operation, and when the pressure of hydrogen in the Dewar is higher than the maximum threshold value, an exhaust pipe (20) controls an intelligent switch (904) of the exhaust pipe to open according to the gas pressure sensed by a pressure sensor in the Dewar to allow the hydrogen to enter a gas tank; in S4, when the DC choppers of the superconducting energy storage device (9) and the fuel cell (10) are controlled, a filter is used, so that the high-frequency component of the power fluctuation is borne by the superconducting energy storage device (9), and the low-frequency component is borne by the fuel cell (10).
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| CN114974793A (en) * | 2022-06-29 | 2022-08-30 | 华中科技大学 | Superconducting energy storage system utilizing liquid hydrogen circulation refrigeration and nitrogen fixation cooling |
| CN116345703A (en) * | 2023-03-08 | 2023-06-27 | 三峡新能源盐城大丰有限公司 | Comprehensive energy system for producing hydrogen based on offshore wind power |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114974793A (en) * | 2022-06-29 | 2022-08-30 | 华中科技大学 | Superconducting energy storage system utilizing liquid hydrogen circulation refrigeration and nitrogen fixation cooling |
| CN116345703A (en) * | 2023-03-08 | 2023-06-27 | 三峡新能源盐城大丰有限公司 | Comprehensive energy system for producing hydrogen based on offshore wind power |
| CN116345703B (en) * | 2023-03-08 | 2023-09-22 | 三峡新能源盐城大丰有限公司 | Comprehensive energy system for producing hydrogen based on offshore wind power |
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