Combined operation system of wind power, photovoltaic and solid oxide electrolysis to produce hydrogen

Abstract

The present invention discloses a combined operation system for producing hydrogen by utilizing wind power, photovoltaic power and solid oxide electrolysis, which includes a steam generation unit; the output end of the distribution network is electrically connected to the solid oxide electrolysis cell stack unit and the steam generation unit respectively; the steam outlet of the resistive electric boiler is connected to the steam inlet of the solid heat storage boiler, and the steam outlet of the solid heat storage boiler is connected to the water vapor inlet of the solid oxide electrolysis cell stack unit. Advantages: clean electric energy is provided to the solid oxide electrolysis cell stack unit and the steam generation unit by the wind power generation unit and the photovoltaic power generation unit, and the steam generation unit provides the clean heat energy required for the electrolysis reaction to the solid oxide electrolysis cell stack unit; the coupling of new energy sources such as wind power and photovoltaic power generation with high-temperature solid oxide electrolysis hydrogen production technology is realized, and a technical route combining high-temperature solid oxide electrolysis hydrogen production technology with non-nuclear energy is created, thereby improving resource utilization.

Description

Technical field:

[0001] The present invention relates to the technical field of hydrogen production using clean energy, and in particular to a system for producing hydrogen by combining wind power, photovoltaic power and solid oxide electrolysis. Background technology:

[0002] With the continuous expansion of wind power and photovoltaic power in recent years, affected by the output characteristics of wind power, photovoltaic power output and electricity load characteristics, wind farms and photovoltaic power stations in most areas have the phenomenon of wind abandonment and light abandonment and power rationing. Since the power grid lacks peak-shaving means such as energy storage facilities, it has to limit the output of wind turbines and photovoltaic modules, which has a significant impact on the operating hours of wind power and photovoltaic power.

[0003] At present, the technologies for producing hydrogen by electrolysis of water include alkaline electrolysis technology, solid polymer electrolysis technology (SPE) and solid oxide electrolysis technology (SOEC); among them, alkaline electrolysis technology is the most mature and has the lowest cost, and has been applied in large-scale hydrogen production, but its efficiency is relatively low. Although SPE electrolysis technology has been improved to a certain extent compared with alkaline electrolysis technology, after taking into account the loss of auxiliary equipment, the system efficiency is still not high, and it is not an ideal solution; high-temperature SOEC technology, which works at around 800°C, has greatly improved electrolysis efficiency compared with alkaline electrolysis technology and SPE electrolysis technology working at around 80°C, and is the most promising water electrolysis hydrogen production technology among the three technologies.

[0004] Since the operating temperature of SOEC is about 800-950℃, high temperature gas-cooled reactors (HTGRs) are usually used to provide both electricity and high-temperature thermal energy. Currently, the electricity and thermal energy supply systems of high temperature gas-cooled reactors are a common research direction at home and abroad, while there has been no in-depth research on the coupling technology of renewable energy such as wind energy and solar energy with high-temperature solid oxide electrolysis cells for hydrogen production.

[0005] In view of the current situation of large-scale abandonment of renewable energy, the high efficiency of high-temperature SOEC water electrolysis to produce hydrogen, and the multi-field application value of hydrogen as both a clean fuel and a chemical raw material, the coupling technology of renewable energy and high-temperature SOEC water electrolysis to produce hydrogen will bring broad application prospects for the promotion of hydrogen energy. Summary of the invention:

[0006] The purpose of the present invention is to provide a system for the combined operation of wind power, photovoltaic power and solid oxide electrolysis to produce hydrogen, which can convert the surplus wind power and photovoltaic power in the power grid into thermal energy for storage, thereby providing a means of peak shaving and valley filling for the power grid; and provides a new energy source for the electrolysis of hydrogen in solid oxide electrolysis cells, namely, utilizing wind energy and solar energy in combination with electric heat storage equipment to provide clean electricity and thermal energy for solid oxide electrolysis cells.

[0007] The present invention is implemented by the following technical scheme: a wind power, photovoltaic and solid oxide electrolysis hydrogen production combined operation system, which includes a wind power generation unit, a photovoltaic power generation unit, a solid oxide electrolysis cell stack unit, a steam generation unit, a heat recovery unit, a hydrogen storage tank, an oxygen storage tank, a pure water preparation unit and a distribution network; the output end of the wind power generation unit and the output end of the photovoltaic power generation unit are respectively electrically connected to the input end of the distribution network, and the output end of the distribution network is respectively electrically connected to the electrical equipment of the solid oxide electrolysis cell stack unit and the electrical equipment of the steam generation unit; the solid oxide The oxygen outlet of the solid oxide electrolyzer stack unit is connected to the oxygen storage tank through the oxygen outlet main pipe, and the hydrogen outlet of the solid oxide electrolyzer stack unit is connected to the hydrogen storage tank through the hydrogen outlet main pipe; the steam generating unit includes a solid heat storage boiler and a resistive electric boiler; the water outlet of the pure water preparation unit is connected to the water inlet of the resistive electric boiler, the steam outlet of the resistive electric boiler is connected to the steam inlet of the solid heat storage boiler through a pipeline, and the steam outlet of the solid heat storage boiler is connected to the water vapor inlet of the solid oxide electrolyzer stack unit through the water vapor inlet main pipe.

[0008] Furthermore, a gas flow control valve is installed on the pipeline between the steam outlet of the resistance electric boiler and the steam inlet of the solid thermal storage boiler.

[0009] Furthermore, the solid oxide electrolysis cell stack unit includes a solid oxide electrolysis cell, an electrolysis hydrogen production transformer and a rectifier inverter; the input end of the electrolysis hydrogen production transformer is electrically connected to the output end of the distribution network, the output end of the electrolysis hydrogen production transformer is electrically connected to the input end of the rectifier inverter, and the output end of the rectifier inverter is electrically connected to the solid oxide electrolysis cell.

[0010] Furthermore, it also includes a stop valve and a check valve connected in series between the hydrogen outlet main pipe and the water vapor inlet main pipe.

[0011] Furthermore, it also includes an electric heating system transformer and a boiler control cabinet; the input end of the electric heating system transformer is electrically connected to the output end of the power distribution network, the output end of the electric heating system transformer is electrically connected to the input end of the boiler control cabinet, and the output end of the boiler control cabinet is electrically connected to the resistive electric boiler and the solid heat storage boiler respectively.

[0012] Furthermore, the heat recovery unit includes a No. 1 preheater and a No. 2 preheater; the oxygen outlet of the oxygen outlet main pipe is connected to the air inlet of the No. 1 preheater, and the air outlet of the No. 1 preheater is connected to the oxygen storage tank through a pipeline; the hydrogen outlet of the hydrogen outlet main pipe is connected to the air inlet of the No. 2 preheater, and the air outlet of the No. 2 preheater is connected to the hydrogen storage tank through a pipeline; the water outlet of the pure water preparation unit is connected to the water inlet of the No. 1 preheater, the water outlet of the No. 1 preheater is connected to the water inlet of the No. 2 preheater, and the water outlet of the No. 2 preheater is connected to the water inlet of the resistance-type electric boiler.

[0013] Furthermore, it also includes an air-water separator No. 1 and an air-water separator No. 2; the air outlet of the No. 1 preheater is connected to the air inlet of the No. 1 air-water separator, and the air outlet of the No. 1 air-water separator is connected to the air inlet of the oxygen storage tank; the air outlet of the No. 2 preheater is connected to the air inlet of the No. 2 air-water separator, and the air outlet of the No. 2 air-water separator is connected to the air inlet of the hydrogen storage tank; the condensed water outlet of the No. 1 air-water separator and the condensed water outlet of the No. 2 air-water separator are both connected to the water outlet of the pure water preparation unit.

[0014] Furthermore, the pure water preparation unit includes a raw water storage tank and a pure water preparation device, and the water outlet of the raw water storage tank is connected to the water inlet of the pure water preparation device.

[0015] Furthermore, the solid heat storage boiler includes a base, a saturated water vapor inlet main pipe, a superheated water vapor outlet main pipe and an insulating furnace shell fixed on the top of the base; a heat storage brick layer is built in the insulating furnace shell, and a plurality of electric heating wires are buried in the heat storage brick layer; a plurality of water vapor heating pipelines are penetrated in the heat storage brick layer, the saturated water vapor inlet main pipe is connected to the inlet of each of the water vapor heating pipelines, and the outlet of each of the water vapor heating pipelines is connected to the superheated water vapor outlet main pipe; a high-temperature fan is installed on the saturated water vapor inlet main pipe.

[0016] The advantages of the present invention are as follows: clean electric energy is provided to the solid oxide electrolysis cell stack unit and the steam generation unit through the wind power generation unit and the photovoltaic power generation unit; the steam generation unit provides the solid oxide electrolysis cell stack unit with clean heat energy required for the electrolysis reaction, that is, the electric energy and heat energy required by the solid oxide electrolysis cell stack unit are both provided by new energy; the present invention does not adopt the existing high-temperature gas-cooled reactor to provide electric energy and heat energy, but adopts renewable energy as electric energy and heat energy. Compared with the existing high-temperature gas-cooled reactor, the present invention is more conducive to saving energy and making full use of renewable energy.

[0017] The heat recovery and utilization unit is used to realize the heat recovery and recycling of hydrogen and oxygen produced by the electrolysis reaction, and the resistive electric boiler and the solid heat storage boiler can be used to convert the abundant wind power and photovoltaic electric energy of the power grid into thermal energy for storage, and a new energy source mode of hydrogen production by electrolysis in solid oxide electrolysis cells is provided, including electric energy and thermal energy, realizing the technical coupling of new energy such as wind power and photovoltaics with high-temperature solid oxide electrolysis for hydrogen production. At the same time, the present invention improves the resource utilization rate, enables the excess new energy electricity to be stored through hydrogen energy and thermal energy, and provides a means of peak shaving and valley filling for the power grid. Description of the drawings:

[0018] Figure 1 It is a structural schematic diagram of the present invention.

[0019] Figure 2 It is a schematic structural diagram of the solid heat storage boiler of the present invention.

[0020] The components in the attached drawings are marked as follows: wind power generation unit 1, wind turbine 1.1, wind power transformer 1.2, photovoltaic power generation unit 2, photovoltaic module 2.1, inverter 2.2, photovoltaic transformer 2.3, solid oxide electrolytic cell stack unit 3, electrolytic hydrogen production transformer 3.1, rectifier inverter 3.2, solid oxide electrolytic cell 3.3, electrolytic cell cathode 3.31, electrolytic cell anode 3.32, electrolyte 3.33, hydrogen outlet main pipe 3.34, water vapor inlet main pipe 3.35, oxygen outlet main pipe 3.36, stop valve 3.4, check valve 3.5, steam generation unit 4, electric heating system transformer 4.1 , boiler control cabinet 4.2, resistive electric boiler 4.3, solid heat storage boiler 4.4, base 4.41, insulated furnace shell 4.42, heat storage brick layer 4.43, electric heating wire 4.44, water vapor heating pipeline 4.45, saturated water vapor inlet main pipe 4.46, superheated water vapor outlet main pipe 4.47, high temperature fan 4.48, gas flow control valve 4.5, heat recovery unit 5, No. 1 preheater 5.1, No. 2 preheater 5.2, No. 1 gas-water separator 5.3, No. 2 gas-water separator 5.4, hydrogen storage tank 6, oxygen storage tank 7, pure water preparation unit 8, raw water storage tank 8.1, pure water preparation device 8.2, distribution network 9. Specific implementation method:

[0021] like Figure 1 and Figure 2 As shown, this embodiment provides a combined operation system for producing hydrogen using wind power, photovoltaics and solid oxide electrolysis, which includes a wind power generation unit 1, a photovoltaic power generation unit 2, a solid oxide electrolysis cell stack unit 3, a steam generation unit 4, a heat recovery unit 5, a hydrogen storage tank 6, an oxygen storage tank 7, a pure water preparation unit 8 and a distribution network 9.

[0022] The output end of the wind power generation unit 1 and the output end of the photovoltaic power generation unit 2 are electrically connected to the input end of the distribution network 9 respectively. The wind power generation unit 1 includes a wind generator 1.1 and a wind power transformer 1.2. The output end of the wind generator 1.1 is electrically connected to the input end of the wind power transformer 1.2, and the output end of the wind power transformer 1.2 is electrically connected to the input end of the distribution network 9; the electric energy generated by the wind power generation unit 1 is supplied to the distribution network 9; the photovoltaic power generation unit 2 includes a photovoltaic module 2.1, an inverter 2.2 and a photovoltaic power transformer 2.3; the output end of the photovoltaic module 2.1 is electrically connected to the input end of the inverter 2.2, the output end of the inverter 2.2 is electrically connected to the input end of the photovoltaic power transformer 2.3, the output end of the photovoltaic power transformer 2.3 is electrically connected to the input end of the distribution network 9, and the electric energy generated by the photovoltaic power generation unit 2 is supplied to the distribution network 9.

[0023] The solid oxide electrolysis cell stack unit 3 includes a solid oxide electrolysis cell 3.3, an electrolysis hydrogen production transformer 3.1 and a rectifier inverter 3.2; the output end of the distribution network 9 is electrically connected to the input end of the electrolysis hydrogen production transformer 3.1 of the solid oxide electrolysis cell stack unit 3, the output end of the electrolysis hydrogen production transformer 3.1 is electrically connected to the input end of the rectifier inverter 3.2, and the output end of the rectifier inverter 3.2 is electrically connected to the solid oxide electrolysis cell 3.3, wherein the positive electrode line of the rectifier inverter 3.2 is electrically connected to the electrolysis cell anode 3.32 of the solid oxide electrolysis cell 3.3, and the negative electrode line of the rectifier inverter 3.2 is electrically connected to the electrolysis cell anode 3.32 of the solid oxide electrolysis cell 3.3. The electrode line is electrically connected to the cathode 3.31 of the solid oxide electrolytic cell 3.3; the new energy power from the wind power generation unit 1 and the photovoltaic power generation unit 2 is transformed by the electrolysis hydrogen production transformer 3.1, and the alternating current is converted into direct current by the rectifier inverter 3.2, and the direct current is passed to the electrode of the solid oxide electrolytic cell 3.3 to perform electrolysis reaction; multiple solid oxide electrolytic cells 3.3 are formed into a stack through a connector, and the connector has two main functions, one is to separate the gas in the cathode chamber and the anode chamber, and the other is to transmit current between the electrolytic cell units. The connector materials currently used are mainly LaCrO3 The solid oxide electrolytic cell 3.3 is made of Ni / YSZ porous metal ceramics as the cathode 3.31, and the anode 3.32 is made of perovskite oxide as the main material. The electrolyte 3.33 in the middle is made of YSZ oxygen ion conductor. After a certain DC voltage is applied to the electrodes on both sides of the solid oxide electrolytic cell 3.3, water molecules undergo electrolysis and decomposition at the cathode 3.31 to produce hydrogen and oxygen ions. The oxygen ions pass through the electrolyte 3.33 to reach the anode 3.32 of the electrolytic cell, where they lose electrons to produce oxygen. Gas; also includes a stop valve 3.4 and a check valve 3.5 connected in series between the outlet of the hydrogen outlet main pipe 3.34 and the outlet of the water vapor inlet main pipe 3.35. The check valve 3.5 can effectively prevent the steam in the water vapor inlet main pipe 3.35 from flowing back into the hydrogen outlet main pipe 3.34, and by controlling the stop valve 3.4, it can ensure that a small amount of hydrogen in the hydrogen outlet main pipe 3.34 enters the water vapor inlet main pipe 3.35, so that water vapor mixed with a small amount of hydrogen enters from the cathode 3.31 of the electrolytic cell. The purpose of mixing hydrogen is to ensure a reducing atmosphere at the cathode of the electrolytic cell and prevent the cathode material Ni from being oxidized.

[0024] The steam generation unit 4 includes an electric heating system transformer 4.1, a boiler control cabinet 4.2, a solid heat storage boiler 4.4 and a resistive electric heating boiler 4.3; the input end of the electric heating system transformer 4.1 is electrically connected to the output end of the distribution network 9, the output end of the electric heating system transformer 4.1 is electrically connected to the input end of the boiler control cabinet 4.2, and the output end of the boiler control cabinet 4.2 is electrically connected to the resistive electric heating boiler 4.3 and the solid heat storage boiler 4.4 respectively; the electric energy generated by the wind power generation unit 1 and the photovoltaic power generation unit 2 is used to generate heat energy for the resistive electric heating boiler 4.3 and the solid heat storage boiler 4.4, that is, the steam generation unit 4 converts the electric energy generated by wind power and photovoltaic power generation into heat energy, wherein the heat storage medium in the solid heat storage boiler 4.4 can store the heat energy; thus, clean electricity is provided to the solid oxide electrolytic cell stack unit 3 and the steam generation unit 4 through the wind power generation unit 1 and the photovoltaic power generation unit 2.

[0025] The cathode 3.31 of the solid oxide electrolytic cell 3.3 is connected to a hydrogen outlet main pipe 3.34 and a water vapor inlet main pipe 3.35, and the anode 3.32 of the electrolytic cell is connected to an oxygen outlet main pipe 3.36; the oxygen outlet of the oxygen outlet main pipe 3.36 is connected to the air inlet of the No. 1 preheater 5.1 of the heat recovery unit 5, the air outlet of the No. 1 preheater 5.1 is connected to the oxygen storage tank 7 through a pipeline, the air outlet of the No. 1 preheater 5.1 is connected to the air inlet of the No. 1 gas-water separator 5.3, and the air outlet of the No. 1 gas-water separator 5.3 is connected to the air inlet of the oxygen storage tank 7; the hydrogen outlet of the hydrogen outlet main pipe 3.34 is connected to the No. 2 The air inlet of the preheater 5.2 is connected, the air outlet of the second preheater 5.2 is connected to the hydrogen storage tank 6 through a pipeline, the air outlet of the second preheater 5.2 is connected to the air inlet of the second gas-water separator 5.4, and the air outlet of the second gas-water separator 5.4 is connected to the air inlet of the hydrogen storage tank 6; the pure water preparation unit 8 includes a raw water storage tank 8.1 and a pure water preparation device 8.2, the water outlet of the raw water storage tank 8.1 is connected to the water inlet of the pure water preparation device 8.2, and the pure water preparation device 8.2 uses EDI deionized water equipment or reverse osmosis pure water equipment to prepare raw pure water; the water outlet of the pure water preparation device 8.2 is connected to the water inlet of the first preheater 5.1, and the water outlet of the first preheater 5.1 is connected to the water inlet of the second preheater 5.4. The inlet is connected to the water inlet of the No. 2 preheater 5.2; both the No. 1 preheater 5.1 and the No. 2 preheater 5.2 are plate heat exchangers; the oxygen generated by electrolysis in the solid oxide electrolysis cell 3.3 is introduced into the No. 1 preheater 5.1, and heat is exchanged with the pure water discharged from the pure water preparation device 8.2, and the pure water is preheated for the first time. The pure water after the first preheating flows into the No. 2 preheater 5.2, and heat is exchanged again with the hydrogen generated by electrolysis in the solid oxide electrolysis cell 3.3, and the pure water is preheated for the second time by the heat of the hydrogen; thus, the heat of the hydrogen and oxygen generated by the solid oxide electrolysis cell 3.3 can be recovered and utilized by the heat recovery unit 5, and the pure water preparation unit 8.2 can be preheated for the second time. The pure water prepared by element 8 is preheated to provide preheated pure water for the steam generating unit 4, so as to realize the energy recycling of the whole system; oxygen and water are separated by the gas-water separator No. 1 5.3, and the separated oxygen is passed into the oxygen storage tank 7 for storage, and hydrogen and water are separated by the gas-water separator No. 2 5.4, and the separated hydrogen is passed into the hydrogen storage tank 6 for storage; the condensate outlet of the gas-water separator No. 1 5.3 and the condensate outlet of the gas-water separator No. 2 5.4 are both connected to the water outlet of the pure water preparation device 8.2; the separated condensed water and the pure water prepared by the pure water preparation device 8.2 are merged into the No. 1 preheater 5.1, so as to realize the recycling and reuse of the condensed water.

[0026] The water outlet of the second preheater 5.2 is connected to the water inlet of the resistance electric boiler 4.3, the steam outlet of the resistance electric boiler 4.3 is connected to the steam inlet of the solid heat storage boiler 4.4 through the gas flow control valve 4.5, and the steam outlet of the solid heat storage boiler 4.4 is connected to the water vapor inlet of the water vapor inlet main pipe 3.35; the pure water after the second preheating is introduced into the resistance electric boiler 4.3, the pure water is heated by the resistance electric boiler 4.3 to generate saturated water vapor, and then the saturated water vapor is heated to superheated water vapor by the solid heat storage boiler 4.4, and the superheated water vapor generated by heating is introduced into the solid oxide electrolytic cell 3.3, the temperature of the superheated water vapor reaches 800°C, and clean heat energy is provided for the electrolysis reaction of the solid oxide electrolytic cell 3.3; the present invention does not use the existing high temperature gas-cooled reactor to provide electricity and heat energy, but uses renewable energy as electricity and heat energy. Compared with the existing high temperature gas-cooled reactor, the present invention is more conducive to saving energy, making full use of renewable energy, and realizing the technical coupling of renewable energy power generation and high temperature solid oxide electrolysis hydrogen production.

[0027] The resistive electric heating boiler 4.3 is a prior art, and the specific structure will not be repeated here. The resistive electric heating boiler 4.3 adopts a high-impedance tubular electric heating component. After the power is turned on, the tubular electric heating component relies on convection heat exchange in the boiler drum, so that the high heat generated by the electric heating component makes the entire boiler drum hot or produces steam. The tubular electric heating component is composed of a metal shell, an electric heating wire and magnesium oxide. The metal tube shell is generally made of stainless steel or No. 10 seamless steel pipe. Magnesium oxide is filled between the metal tube wall and the electric heating wire as an insulator and a heat-conducting medium.

[0028] The solid heat storage boiler 4.4 comprises a base 4.41, a saturated water vapor inlet main pipe 4.46, a superheated water vapor outlet main pipe 4.47 and an insulated furnace shell 4.42 fixed on the top of the base 4.41; a heat storage brick layer 4.43 is built in the insulated furnace shell 4.42, and a plurality of electric heating wires 4.44 are buried in the heat storage brick layer 4.43; a plurality of water vapor heating pipelines 4.45 are penetrated in the heat storage brick layer 4.43, and the saturated water vapor inlet main pipe 4.46 is connected to the inlet of each water vapor heating pipeline 4.45, and each water vapor heating pipeline 4.4 The outlet of 5 is connected with the superheated water steam outlet main pipe 4.47; the saturated water steam inlet main pipe 4.46 is equipped with a high-temperature fan 4.48, and the superheated water steam outlet main pipe 4.47 is connected with the water steam inlet main pipe 3.35; under the action of the high-temperature fan 4.48, the saturated water steam of the resistance electric boiler 4.3 is sent into the water steam heating pipeline 4.45 laid in the solid heat storage boiler 4.4 through the pipeline, and after being heated by the heat storage brick layer 4.43, it is sent into the solid oxide electrolytic cell 3.3 from the water steam inlet main pipe 3.35 to provide a heat source.

[0029] Based on the original structure, the present invention improves the structure of the solid heat storage boiler 4.4. The original solid heat storage boiler realizes heat supply through medium heat exchange, that is, by installing an air-water or air-air heat exchanger on the outside of the solid heat storage boiler 4.4 to realize external heat output. The present invention directly lays the water vapor heating pipeline 4.45 evenly inside the solid heat storage boiler 4.4, that is, between the heat storage bodies of the heat storage brick layer 4.43, thereby reducing the heat exchange link and using the heat storage brick layer 4.43 to directly heat the water vapor; the electric heating wire 4.44 in the solid heat storage boiler 4.4 heats the heat storage brick layer 4.43 after being energized. The heat storage brick layer 4.43 is usually a magnesium-based metal oxide, and the maximum heat storage temperature can reach 900°C. The rated heat storage temperature used in the present invention is 850°C. The solid heat storage boiler 4.4 has two main functions. One is to combine wind power with photovoltaic power. The new energy electric energy is converted into thermal energy and stored. Since the solid heat storage boiler 4.4 itself has a heat storage function, it can be used as a peak-shaving means of the power grid after being connected to the power grid. During the low load period of the power grid, the new energy electricity is stored, and the saturated water vapor is heated by the heat energy stored in the solid heat storage boiler 4. During the peak load period of the power grid, the electric heating power is reduced, making this technology grid-friendly; thereby, it plays the role of smoothing the fluctuations in wind and solar power output, improving resource utilization, and allowing excess new energy electricity to be stored through thermal energy, providing a peak-shaving and valley-filling means for the power grid; secondly, the saturated water vapor generated by the resistance electric boiler 4.3 is heated to 800°C superheated water vapor, providing superheated water vapor for the solid oxide electrolysis cell 3.3; the gas flow rate is adjusted by the gas flow control valve 4.5, thereby achieving control of the temperature of the high-temperature raw water vapor.

[0030] The present invention utilizes a resistive electric boiler 4.3 and a solid heat storage boiler 4.4 to convert the abundant wind power and photovoltaic electric energy of the power grid into thermal energy for storage, and provides a new energy source method for electrolysis and hydrogen production in a solid oxide electrolysis cell 3.3, including electric energy and thermal energy, thereby realizing the coupling of new energy sources such as wind power and photovoltaics with high-temperature solid oxide electrolysis hydrogen production technology. At the same time, the present invention improves resource utilization, enables excess new energy electricity to be stored through hydrogen energy and thermal energy, and provides a means of peak shaving and valley filling for the power grid.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis, characterized in that: It includes a wind power generation unit, a photovoltaic power generation unit, a solid oxide electrolysis cell stack unit, a steam generation unit, a heat recovery unit, a hydrogen storage tank, an oxygen storage tank, a pure water preparation unit and a distribution network; The output end of the wind power generation unit and the output end of the photovoltaic power generation unit are electrically connected to the input end of the power distribution network respectively, and the output end of the power distribution network is electrically connected to the electrical equipment of the solid oxide electrolytic cell stack unit and the electrical equipment of the steam generation unit respectively; The oxygen outlet of the solid oxide electrolytic cell stack unit is connected to the oxygen storage tank through the oxygen outlet main pipe, and the hydrogen outlet of the solid oxide electrolytic cell stack unit is connected to the hydrogen storage tank through the hydrogen outlet main pipe; The steam generation unit includes a solid heat storage boiler and a resistive electric boiler; the water outlet of the pure water preparation unit is connected to the water inlet of the resistive electric boiler, the steam outlet of the resistive electric boiler is connected to the steam inlet of the solid heat storage boiler through a pipeline, and the steam outlet of the solid heat storage boiler is connected to the water vapor inlet of the solid oxide electrolytic cell stack unit through a water vapor intake manifold; It also includes an electric heating system transformer and a boiler control cabinet; the input end of the electric heating system transformer is electrically connected to the output end of the power distribution network, the output end of the electric heating system transformer is electrically connected to the input end of the boiler control cabinet, and the output end of the boiler control cabinet is electrically connected to the resistance electric heating boiler and the solid heat storage boiler respectively; The solid heat storage boiler comprises a base, a saturated water vapor inlet main pipe, a superheated water vapor outlet main pipe and an insulating furnace shell fixed on the top of the base; a heat storage brick layer is built in the insulating furnace shell, and a plurality of electric heating wires are buried in the heat storage brick layer; a plurality of water vapor heating pipelines are penetrated in the heat storage brick layer, the saturated water vapor inlet main pipe is connected with the inlet of each of the water vapor heating pipelines, and the outlet of each of the water vapor heating pipelines is connected with the superheated water vapor outlet main pipe; a high-temperature fan is installed on the saturated water vapor inlet main pipe.

2. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to claim 1 is characterized in that: A gas flow control valve is installed on the pipeline between the steam outlet of the resistance electric boiler and the steam inlet of the solid heat storage boiler.

3. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to claim 1 is characterized in that: The solid oxide electrolytic cell stack unit comprises a solid oxide electrolytic cell, an electrolytic hydrogen production transformer and a rectifier inverter; The input end of the electrolysis hydrogen production transformer is electrically connected to the output end of the power distribution network, the output end of the electrolysis hydrogen production transformer is electrically connected to the input end of the rectifier inverter, and the output end of the rectifier inverter is electrically connected to the solid oxide electrolysis cell.

4. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to claim 1 is characterized in that: It also includes a stop valve and a check valve which are connected in series between the hydrogen outlet main pipe and the water vapor inlet main pipe.

5. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to any one of claims 1 to 4, characterized in that: The heat recovery unit includes a No. 1 preheater and a No. 2 preheater; the oxygen outlet of the oxygen outlet main pipe is connected to the air inlet of the No. 1 preheater, and the air outlet of the No. 1 preheater is connected to the oxygen storage tank through a pipeline; the hydrogen outlet of the hydrogen outlet main pipe is connected to the air inlet of the No. 2 preheater, and the air outlet of the No. 2 preheater is connected to the hydrogen storage tank through a pipeline; the water outlet of the pure water preparation unit is connected to the water inlet of the No. 1 preheater, the water outlet of the No. 1 preheater is connected to the water inlet of the No. 2 preheater, and the water outlet of the No. 2 preheater is connected to the water inlet of the resistance-type electric boiler.

6. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to claim 5 is characterized in that: It also includes an air-water separator No. 1 and an air-water separator No. 2; the air outlet of the No. 1 preheater is connected to the air inlet of the No. 1 air-water separator, and the air outlet of the No. 1 air-water separator is connected to the air inlet of the oxygen storage tank; the air outlet of the No. 2 preheater is connected to the air inlet of the No. 2 air-water separator, and the air outlet of the No. 2 air-water separator is connected to the air inlet of the hydrogen storage tank; the condensed water outlet of the No. 1 air-water separator and the condensed water outlet of the No. 2 air-water separator are both connected to the water outlet of the pure water preparation unit.

7. The combined operation system for producing hydrogen using wind power, photovoltaic power and solid oxide electrolysis according to claim 5 is characterized in that: The pure water preparation unit comprises a raw water storage tank and a pure water preparation device, and a water outlet of the raw water storage tank is connected to a water inlet of the pure water preparation device.

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