Hydrogen energy storage and megawatt hydrogen fuel cell power generation system

Abstract

The invention relates to a hydrogen energy storage and megawatt hydrogen fuel cell power generation system. The hydrogen energy storage and megawatt hydrogen fuel cell power generation system comprises a water electrolysis hydrogen production system, a centralized air supply system, a centralized hydrothermal management system, a megawatt hydrogen fuel cell power generation system and an alternating current inverter system, the water electrolysis hydrogen production system comprises a water electrolysis hydrogen production device, a hydrogen storage unit and an oxygen storage unit, the water electrolysis hydrogen production device is respectively connected with the hydrogen storage unit and the oxygen storage unit, and hydrogen and oxygen are generated and stored by utilizing excessive electrolysis water generated at the peak of renewable energy sources; the centralized air supply system comprises a high-pressure industrial oilless air compressor and an air buffer tank; the centralized hydrothermal management system comprises a cooling unit; the megawatt hydrogen fuel cell power generation system is composed of a plurality of hydrogen fuel cell power generation modules which are connected in parallel, and overall work is not affected when a single module breaks down.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen energy and fuel cells, and in particular to a hydrogen energy storage and megawatt-level hydrogen fuel cell power generation system. Background Art

[0002] With the severe situation of global climate change, countries are seeking low-carbon, clean energy alternatives to reduce greenhouse gas emissions. Hydrogen energy, as a clean and efficient form of energy, is considered an important direction for achieving energy transformation. With the widespread application of renewable energy such as wind power and solar energy, the intermittent and volatile nature of their power generation has put forward higher requirements on the stability of the power grid. As a key means to solve the contradiction between energy supply and demand and improve energy utilization efficiency, the importance of hydrogen energy storage power stations is becoming increasingly prominent.

[0003] Existing hydrogen power stations usually directly use multiple vehicle fuel cell systems integrated into a container. This form of hydrogen fuel cell power generation system is expensive. Since it is exclusively used for vehicles, integrating the fuel cell system in the narrow space of the vehicle will inevitably limit the system power. The current power range is generally 30~240kW. In addition, the solution has a high degree of integration coupling and a complex structure, resulting in high processing costs, and the system is difficult to repair, and the maintenance cost is also very high. Fixed power generation fuel cell systems are generally high-power 500kW~nMW, and are integrated by low-power vehicle fuel cell systems, which will inevitably result in each system having a set of BOP parts, resulting in high system procurement costs. This form of hydrogen fuel cell power generation system also has the general phenomenon of low efficiency: due to its highly coupled structure, the gas flow resistance is large and the system efficiency is low; and because the power of a single system is low, each single machine has a set of BOP components, and the BOP components have large losses, causing the system efficiency to be further reduced; in addition, the control logic is not suitable for fixed power stations: because the control logic used for fixed power generation is different from that of automotive fuel cell systems, most companies have not yet moved beyond the control method of automotive fuel cells, have not specially designed fuel cell systems for fixed power stations, and have not made any progress in the development of control programs based on the characteristics of the power grid.

[0004] Therefore, it is necessary to design a hydrogen energy storage and megawatt-level hydrogen fuel cell power generation system to solve the above-mentioned technical problems. Summary of the invention

[0005] In response to the above technical problems, the purpose of the present invention is to provide a hydrogen energy storage and megawatt-level hydrogen fuel cell power generation system, which can be used in combination with wind power and photovoltaics as an energy storage and power generation device, converting electrical energy into hydrogen energy during the peak period of renewable energy generation, and converting hydrogen energy into electrical energy during the low period of power generation and the peak period of electricity consumption, thereby achieving peak shaving and valley filling and improving the stability and reliability of the power grid.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: A hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system, used for generating electricity and transmitting it to a power grid or electrical equipment, characterized in that the hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system comprises a water electrolysis hydrogen production system, a centralized air supply system, a centralized water heat management system, a megawatt-class hydrogen fuel cell power generation system and an AC inverter system; The water electrolysis hydrogen production system comprises a water electrolysis hydrogen production device 7, a hydrogen storage unit and an oxygen storage unit. The water electrolysis hydrogen production device 7 is connected to the hydrogen storage unit and the oxygen storage unit respectively, and utilizes the excess electricity generated during the peak of renewable energy to electrolyze water to generate hydrogen and oxygen and store them; The hydrogen storage unit includes a hydrogen compressor 8 and a hydrogen storage tank 9; The oxygen storage unit comprises a pure oxygen compressor 1 and a pure oxygen storage tank 3; The centralized air supply system includes a high-pressure industrial oil-free air compressor 2 and an air buffer tank 4; The centralized water heat management system includes a cooling unit 5; The megawatt-class hydrogen fuel cell power generation system is composed of a plurality of hydrogen fuel cell power generation modules 10 connected in parallel; The AC inverter system includes an AC inverter 6; The oxygen outlet of the water electrolysis hydrogen production device 7 is connected to the pure oxygen compressor 1 and the pure oxygen gas storage tank 3 in sequence, and the hydrogen outlet is connected to the hydrogen compressor 8 and the hydrogen gas storage tank 9 in sequence; the high-pressure industrial oil-free air compressor 2 is connected to the air buffer tank 4; the pure oxygen gas storage tank 3, the hydrogen gas storage tank 9 and the air buffer tank 4 are connected to the gas port of the hydrogen fuel cell power generation module 10; the electrode output end of the hydrogen fuel cell power generation module 10 is connected to the AC inverter 6; the water cooling port of the hydrogen fuel cell power generation module 10 is connected to the cooling unit 5; The hydrogen fuel cell power generation module 10 includes a fuel cell stack 11, a hydrogen supply circulation unit, an air intake control unit, a water heat management unit and an electric control unit; The water heat management unit includes a plate heat exchanger 12, an electronic three-way valve 13, an electric heater 14, a cooling water expansion tank 15, a water pump 16 and a coolant impurity filter 17; The air intake control unit includes an air flow meter 20 , a proportional valve 21 , an intercooler 22 , a humidifier 23 , a back pressure valve 24 and a tail exhaust 25 .

[0007] The hydrogen supply circulation unit includes a safety valve 28 , a hydrogen discharge port 29 , a pressure reducing valve 30 , a manual stop valve 31 , a hydrogen filter 32 , a first solenoid valve 33 , a second solenoid valve 34 , a third solenoid valve 35 , an ejector 36 and a water vapor separator 37 .

[0008] The electronic control unit includes a DC / DC converter 42 .

[0009] Among them, the heat exchange pipe on one side of the plate heat exchanger 12 is connected to the cooling unit 5, the liquid inlet end of the heat exchange pipe on the other side is connected to the first port of the electronic three-way valve 13, and the liquid outlet end is connected to the liquid inlet of the water pump 16; the liquid outlet of the water pump 16 is respectively connected to the liquid inlet of the coolant impurity filter 17, the liquid inlet of the intercooler 22 and the liquid inlet of the DC / DC converter 42; the liquid outlet of the coolant impurity filter 17 is connected to the cooling water inlet of the battery stack 11; the cooling water outlet of the battery stack 11 is respectively connected to the second port of the electronic three-way valve 13 and the water inlet of the cooling water expansion water tank 15; the third port of the electronic three-way valve 13 is connected to the liquid inlet of the water pump 16 via the electric heater 14; the liquid outlet of the intercooler 22 and the liquid outlet of the DC / DC converter 42 are connected to the second port of the electronic three-way valve 13; the water outlet of the cooling water expansion water tank 15 is connected to the liquid inlet of the water pump 16.

[0010] The pure oxygen storage tank 3 is connected to the air buffer tank 4, and after being mixed in a controllable proportion in the pipeline, it is connected to the air inlet of the intercooler 22 through the air flow meter 20 and the proportional valve 21; the air outlet of the intercooler 22 is connected to the air inlet of the humidifier 23; the moisture outlet of the humidifier 23 is connected to the air inlet of the fuel cell stack 11; the air outlet of the fuel cell stack 11 is connected to the moisture inlet of the humidifier 23; the air outlet of the humidifier 23 is connected to the tail exhaust 25 through the back pressure valve 24.

[0011] The hydrogen outlet ports of the hydrogen storage tank 9 are respectively connected to the air inlet ends of the pressure reducing valve 30; the air outlet end of the pressure reducing valve 30 is connected to the hydrogen inlet of the fuel cell stack 11 via the manual stop valve 31, the hydrogen filter 32, the first solenoid valve 33, and the ejector 36 in sequence; one end of the safety valve 28 is connected to the pipeline between the ejector 36 and the hydrogen inlet of the fuel cell stack 11, and the other end is connected to the hydrogen discharge port 29; the hydrogen outlet of the fuel cell stack 11 is connected to the air inlet end of the water vapor separator 37, and the first exhaust end of the water vapor separator 37 is connected to the ejector 36; the discharge end of the water vapor separator 37 is connected to the tail exhaust 25 via the second solenoid valve 34, and the second exhaust port of the water vapor separator 37 is connected to the tail exhaust 25 via the third solenoid valve 35.

[0012] The positive output terminal and the negative output terminal of the battery stack 11 are connected to the positive input terminal and the negative input terminal of the DC / DC converter 42, and the positive output terminal and the negative output terminal of the DC / DC converter 42 are connected to the positive input terminal and the negative input terminal of the AC inverter 6; the output terminal of the AC inverter 6 is connected to the power grid or the electrical equipment.

[0013] The water electrolysis hydrogen production system is an ALK alkaline water electrolysis system, an AEM high temperature solid oxide water electrolysis system or a PEM proton exchange membrane water electrolysis system.

[0014] The megawatt-class hydrogen fuel cell power generation system is composed of five 200kw hydrogen fuel cell power generation modules 10 connected in parallel, wherein a failure of a single module does not affect the overall operation.

[0015] The water thermal management unit further includes a first coolant temperature sensor 18 and a second coolant temperature sensor 19; the first coolant temperature sensor 18 is arranged on the pipeline between the outlet of the coolant impurity filter 17 and the cooling water inlet of the fuel cell stack 11; the second coolant temperature sensor 19 is arranged on the pipeline between the cooling water outlet of the fuel cell stack 11 and the water inlet of the cooling and replenishing water expansion water tank 15.

[0016] The air intake control unit further includes an air temperature, humidity and pressure sensor 26 and an air pressure sensor 27; the air temperature, humidity and pressure sensor 26 is arranged on the pipeline between the moisture outlet of the humidifier 23 and the air inlet of the fuel cell stack 11; the air pressure sensor 27 is arranged on the pipeline between the air outlet of the fuel cell stack 11 and the moisture inlet of the humidifier 23.

[0017] The hydrogen supply circulation unit further includes a first hydrogen pressure sensor 38, a second hydrogen pressure sensor 39, a third hydrogen pressure sensor 40 and a fourth hydrogen pressure sensor 41; the first hydrogen pressure sensor 38 is arranged on the pipeline between the pressure reducing valve 30 and the manual stop valve 31; the second hydrogen pressure sensor 39 is arranged on the pipeline between the hydrogen filter 32 and the first solenoid valve 33; the third hydrogen pressure sensor 40 is arranged on the pipeline of the hydrogen inlet of the fuel cell stack 11; the fourth hydrogen pressure sensor 41 is arranged on the pipeline of the hydrogen outlet of the fuel cell stack 11.

[0018] A hydrogen energy storage and a megawatt-class hydrogen fuel cell power generation system cold start method, the method comprising the fastest start mode: The electric heaters 14 of all hydrogen fuel cell power generation modules 10 are working, and the opening of the electronic three-way valve 13 is 0; water passes through the water pump 16, passes through the coolant impurity filter 17, and enters the fuel cell stack 11 after being monitored by the first coolant temperature sensor 18; the circulated water is monitored by the second coolant temperature sensor 19 and reaches the electronic three-way valve 13. Since the opening of the electronic three-way valve 13 is 0, the channel to the plate heat exchanger 12 is closed, and all the water is heated by the electric heater 14 and then returns to the water pump 16; thereby achieving the fastest startup of the megawatt-level hydrogen fuel cell power generation system.

[0019] The method further includes a minimum power consumption startup mode: Only the electric heater 14 of a single hydrogen fuel cell power generation module 10 is working, and the single hydrogen fuel cell power generation module 10 is quickly started with the assistance of the electric heater 14. After the hydrogen fuel cell power generation module 10 enters constant power operation, the electric heater 14 stops working; at this time, the electronic three-way valves 13 of all hydrogen fuel cell power generation modules 10 are fully opened, and the heat generated by the operation of a single hydrogen fuel cell power generation module 10 is used to exchange heat with the plate heat exchanger 12 of other hydrogen fuel cell power generation modules 10 through the cooling unit 5 of the centralized water thermal management system, so as to help start the hydrogen fuel cell power generation module 10 without starting the electric heater 14; thereby achieving the minimum power consumption startup of the megawatt-level hydrogen fuel cell power generation system.

[0020] Compared with the prior art, the present invention has the following beneficial effects: The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system of the present invention adopts centralized air supply, and the whole system is supplied by a high-pressure industrial oil-free air compressor, thereby improving the degree of system integration; pure oxygen generated by electrolysis of water is mixed with air, thereby achieving the purpose of improving reaction efficiency, reducing air compressor power, and reducing BOP cost; by adjusting the mixing ratio of pure oxygen and air, the generation of water in the fuel cell membrane can be controlled to prevent the occurrence of membrane drying; a centralized water and heat management system is adopted, and the fastest start-up and the minimum consumption start-up modes can be achieved through a plate heat exchanger, an electronic heater, and a water pump; multiple hydrogen fuel cell power generation modules are used to generate electricity in parallel, and the failure of a single module does not affect the overall operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A system block diagram of the hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system of the present invention; Figure 2 It is a structural schematic diagram of the hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system of the present invention; Figure 3 is a schematic diagram of a hydrogen fuel cell power generation module 10; Figure 4 This is a flow chart of the startup method of the hydrogen energy storage and megawatt-level hydrogen fuel cell power generation system of the present invention.

[0022] The accompanying drawings are marked as follows: 1. Pure oxygen compressor 2. High-pressure industrial oil-free air compressor 3. Pure oxygen storage tank 4. Air buffer tank 5. Cooling unit 6. AC Inverter 7. Hydrogen production device by water electrolysis 8. Hydrogen compressor 9. Hydrogen gas storage tank 10. Hydrogen fuel cell power generation module 11. Battery stack 12. Plate heat exchanger 13. Electronic three-way valve 14. Electric heater 15. Cooling and water replenishment expansion tank 16. Water pump 17. Coolant impurity filter 18. First coolant temperature sensor 19. Second coolant temperature sensor 20. Air flow meter 21. Proportional valve 22. Intercooler 23. Humidifier 24. Back pressure valve 25. Tail row 26. Air temperature, humidity and pressure sensor 27. Air pressure sensor 28. Safety valve 29. Hydrogen discharge port 30. Pressure reducing valve 31. Manual stop valve 32. Hydrogen filter 33. First solenoid valve 34. Second solenoid valve 35. The third solenoid valve 36. Ejector 37. Water vapor separator 38. The first hydrogen pressure sensor 39. Second hydrogen pressure sensor 40. The third hydrogen pressure sensor 41. Fourth hydrogen pressure sensor 42. DC / DC Converter DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0024] like Figure 1As shown, a hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system is used to generate electricity and transmit it to a power grid or power-consuming equipment. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system includes a water electrolysis hydrogen production system, a centralized air supply system, a centralized water heat management system, a megawatt-class hydrogen fuel cell power generation system and an AC inverter system; The water electrolysis hydrogen production system comprises a water electrolysis hydrogen production device 7, a hydrogen storage unit and an oxygen storage unit. The water electrolysis hydrogen production device 7 is connected to the hydrogen storage unit and the oxygen storage unit respectively, and utilizes the excess electricity generated during the peak of renewable energy to electrolyze water to produce hydrogen and oxygen and store them.

[0025] Preferably, the water electrolysis hydrogen production system is an ALK alkaline water electrolysis system, an AEM high-temperature solid oxide water electrolysis system or a PEM proton exchange membrane water electrolysis system.

[0026] The hydrogen storage unit comprises a hydrogen compressor 8 and a hydrogen storage tank 9, which are used to compress and store hydrogen generated by electrolysis of water.

[0027] The oxygen storage unit comprises a pure oxygen compressor 1 and a pure oxygen storage tank 3, which are used to compress and store oxygen generated by electrolysis of water.

[0028] The centralized air supply system includes a high-pressure industrial oil-free air compressor 2 and an air buffer tank 4 .

[0029] The centralized water heat management system includes a cooling unit 5 .

[0030] The megawatt hydrogen fuel cell power generation system is composed of a plurality of parallel hydrogen fuel cell power generation modules 10. In a preferred embodiment of the present invention, the megawatt hydrogen fuel cell power generation system is composed of five 200kw parallel hydrogen fuel cell power generation modules 10, wherein a single module failure does not affect the overall operation.

[0031] The AC inverter system includes an AC inverter 6, which is used to convert the DC power generated by the hydrogen fuel cell power generation module 10 into the AC power required by the power grid and transmit it to the power grid.

[0032] like Figure 2 As shown, the oxygen outlet end of the water electrolysis hydrogen production device 7 is connected to the pure oxygen compressor 1 and the pure oxygen gas storage tank 3 in sequence, and the hydrogen outlet end is connected to the hydrogen compressor 8 and the hydrogen gas storage tank 9 in sequence; the high-pressure industrial oil-free air compressor 2 is connected to the air buffer tank 4; the pure oxygen gas storage tank 3, the hydrogen gas storage tank 9 and the air buffer tank 4 are connected to the gas port of the hydrogen fuel cell power generation module 10; the electrode output end of the hydrogen fuel cell power generation module 10 is connected to the AC inverter 6; the water cooling port of the hydrogen fuel cell power generation module 10 is connected to the cooling unit 5.

[0033] like Figure 3As shown, the hydrogen fuel cell power generation module 10 includes a fuel cell stack 11, a hydrogen supply circulation unit, an air intake control unit, a water heat management unit and an electronic control unit; The stack 11 has a cooling water inlet, a cooling water outlet, an air inlet (air in), an air outlet (air out), a hydrogen inlet (hydrogen in), a hydrogen outlet (hydrogen out), a positive electrode output terminal (HV+) and a negative electrode output terminal (HV-); The water heat management unit includes a plate heat exchanger 12, an electronic three-way valve 13, an electric heater 14, a cooling water expansion tank 15, a water pump 16, a coolant impurity filter 17, a first coolant temperature sensor (T) 18 and a second coolant temperature sensor (T) 19.

[0034] The air intake control unit includes an air flow meter 20 , a proportional valve 21 , an intercooler 22 , a humidifier 23 , a back pressure valve 24 , a tail exhaust 25 , an air temperature humidity pressure sensor (PTH) 26 and an air pressure sensor (P) 27 .

[0035] The hydrogen supply circulation unit includes a safety valve 28, a hydrogen discharge port 29, a pressure reducing valve 30, a manual stop valve 31, a hydrogen filter 32, a first solenoid valve 33, a second solenoid valve 34, a third solenoid valve 35, an ejector 36, a water vapor separator 37, a first hydrogen pressure sensor 38 (P), a second hydrogen pressure sensor (P) 39, a third hydrogen pressure sensor (P) 40 and a fourth hydrogen pressure sensor (P) 41.

[0036] The electronic control unit includes a DC / DC converter 42 .

[0037] Among them, the heat exchange pipe on one side of the plate heat exchanger 12 is connected to the cooling unit 5, the liquid inlet end of the heat exchange pipe on the other side is connected to the first port of the electronic three-way valve 13, and the liquid outlet end is connected to the liquid inlet of the water pump 16; the liquid outlet of the water pump 16 is respectively connected to the liquid inlet of the coolant impurity filter 17, the liquid inlet (water inlet) of the intercooler 22 and the liquid inlet (water inlet) of the DC / DC converter 42; the liquid outlet of the coolant impurity filter 17 is connected to the cooling water inlet of the battery stack 11; the cooling water outlet of the battery stack 11 is respectively connected to the second port of the electronic three-way valve 13 and the water inlet of the cooling and replenishing water expansion tank 15; The third port of the electronic three-way valve 13 is connected to the liquid inlet of the water pump 16 via the electric heater 14; the liquid outlet (water outlet) of the intercooler 22 and the liquid outlet (water outlet) of the DC / DC converter 42 are connected to the second port of the electronic three-way valve 13; the water outlet of the cooling and replenishing water expansion water tank 15 is connected to the liquid inlet of the water pump 16; the first coolant temperature sensor 18 is arranged on the pipeline between the liquid outlet of the coolant impurity filter 17 and the cooling water inlet of the battery stack 11; the second coolant temperature sensor 19 is arranged on the pipeline between the cooling water outlet of the battery stack 11 and the water inlet of the cooling and replenishing water expansion water tank 15.

[0038] The pure oxygen gas storage tank 3 is connected to the air buffer tank 4, and after being mixed in a controllable proportion in the pipeline, it is connected to the air inlet (air inlet) of the intercooler 22 through the air flow meter 20 and the proportional valve 21; the air outlet (air outlet) of the intercooler 22 is connected to the air inlet (dry inlet) of the humidifier 23; the moisture outlet (wet outlet) of the humidifier 23 is connected to the air inlet of the fuel cell stack 11; the air outlet of the fuel cell stack 11 is connected to the moisture inlet (wet inlet) of the humidifier 23; the air outlet (air outlet) of the humidifier 23 is connected to the tail exhaust 25 through the back pressure valve 24; the air temperature, humidity and pressure sensor 26 is arranged on the pipeline between the moisture outlet of the humidifier 23 and the air inlet of the fuel cell stack 11; the air pressure sensor 27 is arranged on the pipeline between the air outlet of the fuel cell stack 11 and the moisture inlet of the humidifier 23.

[0039] The hydrogen outlet ports of the hydrogen storage tank 9 are respectively connected to the air inlet ends of the pressure reducing valve 30; the air outlet end of the pressure reducing valve 30 is connected to the hydrogen inlet of the fuel cell stack 11 via the manual stop valve 31, the hydrogen filter 32, the first solenoid valve 33, and the ejector 36 in sequence; one end of the safety valve 28 is connected to the pipeline between the ejector 36 and the hydrogen inlet of the fuel cell stack 11, and the other end is connected to the hydrogen exhaust port 29; the hydrogen outlet of the fuel cell stack 11 is connected to the air inlet end of the water vapor separator 37, and the first exhaust end of the water vapor separator 37 is connected to the ejector 36; the water vapor separator 37 is connected to the air inlet end of the fuel cell stack 11, and the first exhaust end of the water vapor separator 37 is connected to the ejector 36; The discharge end of the separator 37 is connected to the tail drain 25 via the second solenoid valve 34, and the second exhaust port of the water vapor separator 37 is connected to the tail drain 25 via the third solenoid valve 35; the first hydrogen pressure sensor 38 is arranged on the pipeline between the pressure reducing valve 30 and the manual stop valve 31; the second hydrogen pressure sensor 39 is arranged on the pipeline between the hydrogen filter 32 and the first solenoid valve 33; the third hydrogen pressure sensor 40 is arranged on the pipeline of the hydrogen inlet of the fuel cell stack 11; the fourth hydrogen pressure sensor 41 is arranged on the pipeline of the hydrogen outlet of the fuel cell stack 11.

[0040] The positive output terminal (HV+) and the negative output terminal (HV-) of the battery stack 11 are connected to the positive input terminal (IN+) and the negative input terminal (IN-) of the DC / DC converter 42, and the positive output terminal (OUT+) and the negative output terminal (OUT-) of the DC / DC converter 42 are connected to the positive input terminal and the negative input terminal of the AC inverter 6; the output terminal of the AC inverter 6 is connected to the power grid or electrical equipment.

[0041] The working process of the present invention is as follows: like Figure 4 As shown, when the megawatt-class hydrogen fuel cell power generation system of a hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system of the present invention is cold started, it includes two starting modes: the fastest start and the minimum power consumption start; wherein, The fastest way to start: The electric heaters 14 of all hydrogen fuel cell power generation modules 10 are working, and the opening of the electronic three-way valve 13 is 0; water passes through the water pump 16, passes through the coolant impurity filter 17, and enters the fuel cell stack 11 after being monitored by the first coolant temperature sensor 18; the circulated water is monitored by the second coolant temperature sensor 19 and reaches the electronic three-way valve 13. Since the opening of the electronic three-way valve 13 is 0, the channel to the plate heat exchanger 12 is closed, and all the water is heated by the electric heater 14 and then returns to the water pump 16; thereby achieving the fastest startup of the megawatt-level hydrogen fuel cell power generation system.

[0042] Minimum power consumption startup mode: Only the electric heater 14 of a single hydrogen fuel cell power generation module 10 works, and the single hydrogen fuel cell power generation module 10 starts quickly with the assistance of the electric heater 14. After the hydrogen fuel cell power generation module 10 enters constant power operation, the electric heater 14 stops working. At this time, the electronic three-way valves 13 of all hydrogen fuel cell power generation modules 10 are fully opened, and the heat generated by the operation of a single hydrogen fuel cell power generation module 10 is used to exchange heat with the plate heat exchanger 12 of other hydrogen fuel cell power generation modules 10 through the cooling unit 5 of the centralized water heat management system, so as to help start the hydrogen fuel cell power generation module 10 without starting the electric heater 14; thereby achieving the minimum power consumption start-up of the megawatt-level hydrogen fuel cell power generation system.

[0043] The water electrolysis hydrogen production system uses the excess electricity generated during the peak of renewable energy to electrolyze water to produce hydrogen and oxygen and store them; oxygen is mixed with air to reduce the power of the air compressor and reduce production costs; by adjusting the mixing ratio of oxygen and air, the generation of water in the fuel cell membrane can be controlled to prevent the membrane from being too dry and ensure the working environment. The compressed dry mixed air passes through the air flow meter 20 and the proportional valve 21 to enter the intercooler 22 for cooling, and then enters the humidifier 23 for humidification. The humidified mixed air is monitored by the air temperature, humidity and pressure sensor 26 and enters the fuel cell stack 11; the remaining air after the reaction is monitored by the air pressure sensor 27 from the fuel cell stack 11, and then discharged to the tail exhaust 25 through the humidifier 23 and the back pressure valve 24.

[0044] The compressed hydrogen is decompressed through the pressure reducing valve 30, monitored by the first hydrogen pressure sensor 38, and reaches the hydrogen filter 32 through the manual stop valve 31. It is monitored by the second hydrogen pressure sensor 39 and enters the first solenoid valve 33, to the ejector 36, and enters the fuel cell stack 11 through the third hydrogen pressure sensor 40. If the pressure is too high during the process and exceeds the safety pressure of the safety valve 28, the safety valve 28 automatically opens to release gas until the pressure returns to normal. The hydrogen after the reaction is monitored by the fourth hydrogen pressure sensor 41 and reaches the water vapor separator 37 for water vapor separation. Most of the separated hydrogen enters the ejector 36 and enters the fuel cell stack 11 again, and a small amount of hydrogen and water vapor are discharged into the atmosphere through the tail exhaust 25.

[0045] The electricity generated by the battery stack 11 is converted into high voltage electricity through the DC / DC converter 42, and then converted into three-phase AC power through the AC inverter 6, and transmitted to the power grid or electrical equipment.

Claims

1. A hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system, used to generate electricity and transmit it to a power grid or power-consuming equipment, characterized in that: The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system includes a water electrolysis hydrogen production system, a centralized air supply system, a centralized water heat management system, a megawatt-class hydrogen fuel cell power generation system and an AC inverter system; The water electrolysis hydrogen production system comprises a water electrolysis hydrogen production device (7), a hydrogen storage unit and an oxygen storage unit. The water electrolysis hydrogen production device (7) is connected to the hydrogen storage unit and the oxygen storage unit respectively, and utilizes excess electricity generated during the peak period of renewable energy to electrolyze water to generate hydrogen and oxygen and store them; The hydrogen storage unit comprises a hydrogen compressor (8) and a hydrogen storage tank (9); The oxygen storage unit comprises a pure oxygen compressor (1) and a pure oxygen storage tank (3); The centralized air supply system comprises a high-pressure industrial oil-free air compressor (2) and an air buffer tank (4); The centralized water heat management system comprises a cooling unit (5); The megawatt-class hydrogen fuel cell power generation system is composed of a plurality of hydrogen fuel cell power generation modules (10) connected in parallel; The AC inverter system comprises an AC inverter (6); The oxygen outlet of the water electrolysis hydrogen production device (7) is connected in sequence to a pure oxygen compressor (1) and a pure oxygen gas storage tank (3), and the hydrogen outlet is connected in sequence to a hydrogen compressor (8) and a hydrogen gas storage tank (9); the high-pressure industrial oil-free air compressor (2) is connected to an air buffer tank (4); the pure oxygen gas storage tank (3), the hydrogen gas storage tank (9) and the air buffer tank (4) are connected to the gas port of a hydrogen fuel cell power generation module (10); the electrode output end of the hydrogen fuel cell power generation module (10) is connected to an AC inverter (6); and the water cooling port of the hydrogen fuel cell power generation module (10) is connected to a cooling unit (5); The hydrogen fuel cell power generation module (10) comprises a fuel cell stack (11), a hydrogen supply circulation unit, an air intake control unit, a water heat management unit and an electronic control unit; The water heat management unit comprises a plate heat exchanger (12), an electronic three-way valve (13), an electric heater (14), a cooling water expansion tank (15), a water pump (16) and a coolant impurity filter (17); The air intake control unit comprises an air flow meter (20), a proportional valve (21), an intercooler (22), a humidifier (23), a back pressure valve (24) and a tail exhaust (25); The hydrogen supply circulation unit comprises a safety valve (28), a hydrogen discharge port (29), a pressure reducing valve (30), a manual stop valve (31), a hydrogen filter (32), a first solenoid valve (33), a second solenoid valve (34), a third solenoid valve (35), an ejector (36) and a water vapor separator (37); The electronic control unit comprises a DC / DC converter (42); The heat exchange pipe on one side of the plate heat exchanger (12) is connected to the cooling unit (5), the liquid inlet end of the heat exchange pipe on the other side is connected to the first port of the electronic three-way valve (13), and the liquid outlet end is connected to the liquid inlet of the water pump (16); the liquid outlet of the water pump (16) is respectively connected to the liquid inlet of the coolant impurity filter (17), the liquid inlet of the intercooler (22) and the liquid inlet of the DC / DC converter (42); the liquid outlet of the coolant impurity filter (17) is connected to the cooling water inlet of the fuel cell stack (11). The cooling water outlet of the battery stack (11) is respectively connected to the second port of the electronic three-way valve (13) and the water inlet of the cooling and replenishing water expansion water tank (15); the third port of the electronic three-way valve (13) is connected to the liquid inlet of the water pump (16) via the electric heater (14); the liquid outlet of the intercooler (22) and the liquid outlet of the DC / DC converter (42) are connected to the second port of the electronic three-way valve (13); the water outlet of the cooling and replenishing water expansion water tank (15) is connected to the liquid inlet of the water pump (16); The pure oxygen storage tank (3) and the air buffer tank (4) are connected, and after being mixed in a controllable proportion in the pipeline, they are connected to the air inlet of the intercooler (22) through an air flow meter (20) and a proportional valve (21); the air outlet of the intercooler (22) is connected to the air inlet of a humidifier (23); the moisture outlet of the humidifier (23) is connected to the air inlet of the fuel cell stack (11); the air outlet of the fuel cell stack (11) is connected to the moisture inlet of the humidifier (23); the air outlet of the humidifier (23) is connected to the tail exhaust (25) through a back pressure valve (24); The hydrogen outlet port of the hydrogen storage tank (9) is connected to the air inlet end of the pressure reducing valve (30); the air outlet end of the pressure reducing valve (30) is connected to the hydrogen inlet of the fuel cell stack (11) via the manual stop valve (31), the hydrogen filter (32), the first solenoid valve (33), and the ejector (36) in sequence; one end of the safety valve (28) is connected to the pipeline between the ejector (36) and the hydrogen inlet of the fuel cell stack (11), and the other end is connected to the hydrogen discharge port (29); the hydrogen outlet of the fuel cell stack (11) is connected to the air inlet end of the water vapor separator (37), and the first exhaust end of the water vapor separator (37) is connected to the ejector (36); the liquid discharge end of the water vapor separator (37) is connected to the tail exhaust (25) via the second solenoid valve (34), and the second exhaust port of the water vapor separator (37) is connected to the tail exhaust (25) via the third solenoid valve (35); The positive output terminal and the negative output terminal of the battery stack (11) are connected to the positive input terminal and the negative input terminal of the DC / DC converter (42), and the positive output terminal and the negative output terminal of the DC / DC converter (42) are connected to the positive input terminal and the negative input terminal of the AC inverter (6); the output terminal of the AC inverter (6) is connected to a power grid or an electrical device.

2. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system according to claim 1, characterized in that: The water electrolysis hydrogen production system is an ALK alkaline water electrolysis system, an AEM high temperature solid oxide water electrolysis system or a PEM proton exchange membrane water electrolysis system.

3. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system according to claim 1, characterized in that: The megawatt-class hydrogen fuel cell power generation system is composed of five 200 kW hydrogen fuel cell power generation modules (10) connected in parallel, wherein a failure of a single module does not affect the overall operation.

4. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system according to claim 1, characterized in that: The water thermal management unit further comprises a first coolant temperature sensor (18) and a second coolant temperature sensor (19); the first coolant temperature sensor (18) is arranged on a pipeline between a liquid outlet of a coolant impurity filter (17) and a cooling water inlet of a fuel cell stack (11); and the second coolant temperature sensor (19) is arranged on a pipeline between a cooling water outlet of a fuel cell stack (11) and a water inlet of a cooling and replenishing water expansion tank (15).

5. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system according to claim 1, characterized in that: The air intake control unit further comprises an air temperature, humidity and pressure sensor (26) and an air pressure sensor (27); the air temperature, humidity and pressure sensor (26) is arranged on a pipeline between a moisture outlet of the humidifier (23) and an air inlet of the fuel cell stack (11); and the air pressure sensor (27) is arranged on a pipeline between the air outlet of the fuel cell stack (11) and the moisture inlet of the humidifier (23).

6. The hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system according to claim 1, characterized in that: The hydrogen supply circulation unit further comprises a first hydrogen pressure sensor (38), a second hydrogen pressure sensor (39), a third hydrogen pressure sensor (40) and a fourth hydrogen pressure sensor (41); the first hydrogen pressure sensor (38) is arranged on the pipeline between the pressure reducing valve (30) and the manual stop valve (31); the second hydrogen pressure sensor (39) is arranged on the pipeline between the hydrogen filter (32) and the first solenoid valve (33); the third hydrogen pressure sensor (40) is arranged on the pipeline of the hydrogen inlet of the fuel cell stack (11); and the fourth hydrogen pressure sensor (41) is arranged on the pipeline of the hydrogen outlet of the fuel cell stack (11).

7. A cold start method for a megawatt-class hydrogen fuel cell power generation system applied to the hydrogen energy storage and megawatt-class hydrogen fuel cell power generation system of claim 1, characterized in that: The methods include the fastest startup mode: The electric heaters (14) of all hydrogen fuel cell power generation modules (10) are working, and the opening of the electronic three-way valve (13) is (0); water passes through the water pump (16), passes through the coolant impurity filter (17), and enters the fuel cell stack (11) after being monitored by the first coolant temperature sensor (18); the circulated water is monitored by the second coolant temperature sensor (19) and reaches the electronic three-way valve (13). Since the opening of the electronic three-way valve (13) is (0), the passage to the plate heat exchanger (12) is closed, and all the water is heated by the electric heater (14) and then returns to the water pump (16); thereby achieving the fastest startup of the megawatt-level hydrogen fuel cell power generation system.

8. The cold start method of a megawatt-class hydrogen fuel cell power generation system according to claim 7, characterized in that: The method further includes a minimum power consumption startup mode: Only the electric heater (14) of a single hydrogen fuel cell power generation module (10) works, and the single hydrogen fuel cell power generation module (10) is quickly started with the assistance of the electric heater (14). After the hydrogen fuel cell power generation module (10) enters constant power operation, the electric heater (14) stops working; at this time, the electronic three-way valves (13) of all hydrogen fuel cell power generation modules (10) are fully opened, and heat generated by the operation of the single hydrogen fuel cell power generation module (10) is used to exchange heat with the plate heat exchangers (12) of other hydrogen fuel cell power generation modules (10) through the cooling unit (5) of the centralized water heat management system, thereby helping to start the hydrogen fuel cell power generation module (10) without starting the electric heater (14); thereby achieving the minimum power consumption start-up of the megawatt-level hydrogen fuel cell power generation system.

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