Method and device for manufacturing liquid hydrogen by offshore off-grid superconducting wind turbine

A device for manufacturing liquid hydrogen by offshore off-grid superconducting wind turbine, comprising:

• a liquid preparation platform (1), used as a supporting platform;
• an offshore off-grid superconducting wind turbine generator (2), used for wind power generation;
• a seawater electrolysis unit (3), used for electrolyzing seawater to obtain hydrogen;
• a hydrogen liquefaction unit (4), used for liquefying the hydrogen into liquid hydrogen;
• a liquid hydrogen storage unit (5), used for storing the prepared liquid hydrogen;
• a standby power module (6);
• and
• a control unit (7),
• wherein the seawater electrolysis unit (3), the hydrogen liquefaction unit (4) and the liquid hydrogen storage unit (5) are connected in sequence and respectively arranged on the liquid preparation platform (1);
• power ends of the seawater electrolysis unit (3) and the hydrogen liquefaction unit (4) are connected with a power output end of the offshore off-grid superconducting wind turbine generator (2);
• and an output end of the hydrogen liquefaction unit (4) or an output end of the liquid hydrogen storage unit (5) is connected with a coolant input port of the offshore off-grid superconducting wind turbine generator (2) to output the liquid hydrogen as a refrigerant of the offshore off-grid superconducting wind turbine generator (2),
• wherein the seawater electrolysis unit (3) comprises a seawater desalination component (31) and a water electrolysis hydrogen production module (32) which are connected with each other,
• wherein the seawater desalination component (31) comprises a seawater pump (311), a multistage filtration component (312), a booster pump (313) and a reverse osmosis filtration component (314) which are connected in sequence, an output end of the reverse osmosis filtration component (314) comprises a fresh water outlet and a brine outlet, and the seawater pump (311) and booster pump (313) are connected with the power output end of the offshore off-grid superconducting wind turbine generator (2),
• wherein the water electrolysis hydrogen production module (32) comprises a PEM electrolytic bath (321) and an AC-DC converter (322), the PEM electrolytic bath (321) comprises an anode plate (323) and a cathode plate (324) which are arranged in a gap, an anode diffusion layer (325), a proton exchange membrane (326) and a cathode diffusion layer (327) are sequentially arranged between the anode plate (323) and the cathode plate (324) in a gap, a surface of a side, close to the anode diffusion layer (325), of the proton exchange membrane (326) is provided with an anode catalyst layer (328), a surface of a side, close to the cathode diffusion layer (327), of the proton exchange membrane (326) is provided with a cathode catalyst layer (329), an AC side of the AC-DC converter (322) is connected with the power output end of the offshore off-grid superconducting wind turbine generator (2), and a DC side of the AC-DC converter (322) is connected with the anode plate (323) and the cathode plate (324),
• wherein the hydrogen liquefaction unit (4) comprises:
• a hydrogen-helium heat exchanger (42), used for hydrogen-helium heat exchange so as to realize hydrogen liquidation;
• a helium refrigeration module (43), used for using helium as a refrigerant to provide helium refrigeration for hydrogen-helium heat exchange;
• a hydrogen liquefaction module (44),
• wherein the hydrogen liquefaction module (44) is interconnected with a hydrogen transmission channel in the hydrogen-helium heat exchanger (42);
• the helium refrigeration module (43) is interconnected with a helium transmission channel in the hydrogen-helium heat exchanger (42);
• and a liquid hydrogen output port of the hydrogen liquefaction module (44) is connected with the liquid hydrogen storage unit (5),
• wherein the helium refrigeration module (43) comprises a helium compressor (431), a primary helium heat exchanger (432), a liquid nitrogen precooler (433), a secondary helium heat exchanger (434) and a helium expander (435), an output end of the helium compressor (431) is connected with an inlet of the helium transmission channel of the hydrogen-helium heat exchanger (42) through a first heat exchange channel of the primary helium heat exchanger (432), a first precooling channel of the liquid nitrogen precooler (433), a second heat exchange channel of the secondary helium heat exchanger (434), and the helium expander (435) in sequence, and an outlet of the helium transmission channel of the hydrogen-helium heat exchanger (42) is connected with a helium inlet of the helium compressor (431) through a third heat exchange channel of the secondary helium heat exchanger (434) and a fourth heat exchange channel of the primary helium heat exchanger (432);
• the hydrogen liquefaction module (44) comprises a hydrogen compressor (441), a primary hydrogen heat exchanger (442), a secondary hydrogen heat exchanger (443), a throttle valve (444) and a gas-liquid separator (445), an output end of the water electrolysis hydrogen production module (32) passes through the hydrogen compressor (441), a fifth heat exchange channel of the primary hydrogen heat exchanger (442), a second precooling channel of the liquid nitrogen precooler (433), a sixth heat exchange channel of the secondary hydrogen heat exchanger (443), the hydrogen transmission channel of the hydrogen-helium heat exchanger (42), and the throttle valve (444) in sequence to enter the gas-liquid separator (445), a top of the gas-liquid separator (445) is provided with a hydrogen outlet, the hydrogen outlet is connected with a hydrogen inlet of the hydrogen compressor (441) after passing through a seventh heat exchange channel of the secondary hydrogen heat exchanger (443) and an eighth heat exchange channel of the primary hydrogen heat exchanger (442) in sequence, and a liquid hydrogen output port of the gas-liquid separator (445) is connected with the liquid hydrogen storage unit (5),
• wherein the liquid hydrogen storage unit (5) comprises a liquid hydrogen storage tank which is composed of an outer shell (51) and an inner container (52) and of a double-layer structure, a vacuum or thermal insulation material layer (53) is arranged between the outer shell (51) and the inner container (52), and the liquid hydrogen storage tank is respectively provided with a liquid hydrogen filling port (54), a liquid hydrogen discharge port (55), and a hydrogen discharge port (56),
• wherein the offshore off-grid superconducting wind turbine generator (2) comprises a superconducting generator (21), a converter (22) and a transformer (23) which are connected in sequence, the superconducting generator (21) is connected with a superconducting liquid hydrogen refrigeration unit (24) for cooling a superconductor in the superconducting generator (21), and the output end of the hydrogen liquefaction unit (4) or an input end of the liquid hydrogen storage unit (5) is connected with a coolant input port of the superconducting liquid hydrogen refrigeration unit (24) to output the liquid hydrogen as the refrigerant of the offshore off-grid superconducting wind turbine generator (2),
• wherein the superconducting liquid hydrogen refrigeration unit (24) comprises a hydrogen storage cold box (241), a low-temperature circulating pump (242), a refrigerator (243) and a heat exchanger (244), the hydrogen storage cold box (241) is provided with the coolant input port of the superconducting liquid hydrogen refrigeration unit (24) for inputting the liquid hydrogen, the low-temperature circulating pump (242), the refrigerator (243) and the heat exchanger (244) are connected end to end to form a liquid hydrogen flow circuit, and a liquid hydrogen output end of the hydrogen storage cold box (241) is connected with the liquid hydrogen flow circuit for supplying the liquid hydrogen for the liquid hydrogen flow circuit,
• wherein an output end of the standby power module (6) is respectively connected with the power ends of the seawater electrolysis unit (3) and the hydrogen liquefaction unit (4);
• the standby power module (6) is a storage battery;
• and the storage battery is connected with the power output end of the offshore off-grid superconducting wind turbine generator (2) for charging;
• or the standby power module (6) is a hydrogen fuel cell;
• and a hydrogen input end of the hydrogen fuel cell is connected with the output end of the hydrogen liquefaction unit (4) or an input end of the liquid hydrogen storage unit (5) to use hydrogen as a fuel of the hydrogen fuel cell,
• wherein the offshore off-grid superconducting wind turbine generator (2) further comprises a wind speed sensor connected with the control unit (7), so that the control unit (7) is capable of obtaining a current available power P according to a wind speed sensed by the wind speed sensor;
• an output end of the transformer (23) is provided with a voltage transformer and a current transformer to detect an output power Pwt of the offshore off-grid superconducting wind turbine generator (2);
• the offshore off-grid superconducting wind turbine generator (2) is provided with a pitch control mechanism connected with the control unit (7), for controlling a rotation speed of a blade of the superconducting generator (21) to adjust the output power Pwt of the offshore off-grid superconducting wind turbine generator (2);
• a control end of the refrigerator (243) is connected with the control unit (7) for adjusting a refrigeration power Pr of the superconducting liquid hydrogen refrigeration unit (24);
• a control end of the AC-DC converter (322) is connected with the control unit (7) for adjusting a electrolysis power Ph of the water electrolysis hydrogen production module (32);
• a control end of the standby power module (6) is connected with the control unit (7) for adjusting an output power Pg of the standby power module (6),
• wherein the control unit (7) is configured to schedule the output power Pwt of the offshore off-grid superconducting wind turbine generator (2), the electrolysis power Ph of the water electrolysis hydrogen production module (32), and the output power Pg of the standby power module (6) in various modes as follows, to ensure a stable operation of the superconducting liquid hydrogen refrigeration unit (24):
• if P>Phmax+Prmax+Py, then the output power PWt of the offshore off-grid superconducting wind turbine generator (2) is limited by controlling the rotation speed of the blade of the superconducting generator (21), so that Pwt=Phmax+Prmax+Py, and the water electrolysis hydrogen production module (32) is controlled to operate in a maximum electrolytic power Phmax of the water electrolysis hydrogen production module (32);
• if Phmin+Prmin+Py<P≤Phmax+Prmax+Py, then the output power PWt of the offshore off-grid superconducting wind turbine generator (2) is limited by controlling the rotation speed of the blade of the superconducting generator (21), so that Pwt=P, and the electrolysis power Ph of the water electrolysis hydrogen production module (32) is controlled to be equal to PWt−Pr− Py;
• if Prmin<P≤Phmin+Prmin+Py, then the output power Pwt of the offshore off-grid superconducting wind turbine generator (2) is limited by controlling the rotation speed of the blade of the superconducting generator (21), so that Pwt=Pr, and the electrolysis power Ph of the water electrolysis hydrogen production module (32) is controlled to be equal to 0;
• if P≤Prmin, then the standby power module (6) is started to produce power and the output power Pg of the standby power module (6) is controlled to be equal to Pr−Pwt, and the electrolysis power Ph of the water electrolysis hydrogen production module (32) is controlled to be equal to 0,
• wherein Prmax is a maximum refrigeration power of the superconducting liquid hydrogen refrigeration unit (24), Prmin is a minimum refrigeration power of the superconducting liquid hydrogen refrigeration unit (24) and Prmax and Prmin are equipment parameters of the superconducting liquid hydrogen refrigeration unit (24);
• Phmax is a maximum electrolysis power of the water electrolysis hydrogen production module (32), Phmin is a minimum electrolysis power of the water electrolysis hydrogen production module (32), and Phmax and Phmin are equipment parameters of the water electrolysis hydrogen production module (32);
• and Py is required total power consumption of the seawater desalination component (31), the hydrogen liquefaction unit (4) and the liquid hydrogen storage unit (5).