System and method for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel

Abstract

The present invention relates to a system and method for peak load regulation of a thermal power plant by using electrolytic hydrogen production and hydrogen mixed fuel, the system comprising a thermal power generation system, a water electrolysis hydrogen production system, a gas turbine system and a control system; the thermal power generation system is connected to the water electrolysis hydrogen production system through a plant power system, and is used to supply power to the water electrolysis hydrogen production system through the plant power system to prepare hydrogen; the hydrogen prepared by the water electrolysis hydrogen production system is premixed with the natural gas of the gas turbine system in a mixing chamber to form a hydrogen mixed fuel; the control system is connected to the thermal power generation system and the water electrolysis hydrogen production system, and is used to obtain the AGC load instruction of the power grid in real time, and adjust the output of the water electrolysis hydrogen production system according to the operating load of the thermal power generation unit, so that the thermal power generation unit can maintain a long-term stable load operation. The present invention can reduce the amount of natural gas while improving the thermal efficiency of the gas turbine, thereby achieving the purpose of low carbon and environmental protection.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal power generation, and in particular relates to a system and method for peak load regulation of a thermal power plant by utilizing electrolytic hydrogen production and hydrogen mixed fuel. Background Art

[0002] In recent years, under the requirements of green and low-carbon development, the installed capacity of renewable energy (wind power, photovoltaic, nuclear power, etc.) in my country has increased significantly and will occupy an increasingly large proportion in the future power structure. Wind power, photovoltaic power generation and other sources of electricity are relatively random and volatile, and the impact of power generation on the grid is relatively large, which requires stable thermal power units to perform peak and frequency regulation. However, thermal power units that frequently change load or operate at low load following AGC (Automatic Generation Control) instructions face the risks of increased coal consumption, excessive pollutant emissions and shortened equipment life.

[0003] At present, the biggest problem of thermal power units following the AGC instructions of the power grid for frequency conversion and peak regulation is that the load adjustment of the thermal power units cannot keep up with the changes in the AGC instructions, and there are characteristics of lag and inaccuracy in regulation. Therefore, equipping thermal power plants with large-scale energy storage systems is an important means to achieve indirect peak and frequency regulation of thermal power units. For example, the characteristics of fast startup and fast output regulation of water electrolysis hydrogen production devices can be used to accurately regulate the peak and frequency of thermal power units. However, this method has the following technical defects: if the output configuration of the electrolysis hydrogen production device is too small, the effect of peak and frequency regulation is limited; if the output configuration is large, there is a problem of inconvenient storage and utilization of the prepared hydrogen. Summary of the invention

[0004] The purpose of the present invention is to provide a system and method for peak load regulation of thermal power plants using hydrogen produced by electrolysis and hydrogen mixed fuels. A gas turbine and a water electrolysis hydrogen production system are coordinated, and the hydrogen produced by water electrolysis is mixed with natural gas and sent to the gas turbine for combustion. While improving the thermal efficiency of the gas turbine, the use of natural gas can be reduced, thereby achieving the goal of low carbon and environmental protection.

[0005] The present invention provides a system for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel, comprising a thermal power generation system, a water electrolysis hydrogen production system, a gas turbine system and a control system;

[0006] The thermal power generation system is connected to the water electrolysis hydrogen production system through the plant power system, and is used to supply power to the water electrolysis hydrogen production system through the plant power system to prepare hydrogen;

[0007] The hydrogen produced by the water electrolysis hydrogen production system is premixed with the natural gas of the gas turbine system in a mixing chamber to form a hydrogen mixed fuel;

[0008] The control system is connected with the thermal power generation system and the water electrolysis hydrogen production system to obtain the AGC load instructions of the power grid in real time and adjust the output of the water electrolysis hydrogen production system according to the operating load of the thermal power generating unit, so as to keep the thermal power generating unit in stable load operation for a long time.

[0009] Furthermore, the water electrolysis hydrogen production system is one or a combination of alkaline water electrolysis hydrogen production equipment, proton exchange membrane electrolysis hydrogen production equipment, and solid oxide electrolysis hydrogen production equipment.

[0010] Furthermore, the output selection of the water electrolysis hydrogen production system is determined based on the output parameters of the gas turbine system and the maximum hydrogen blending ratio allowed by the gas turbine.

[0011] Furthermore, the blending ratio of hydrogen in the hydrogen mixed fuel is adjustable from 0 to 100%.

[0012] The present invention also provides a method for peak load regulation of a thermal power plant using the above system, comprising the following steps:

[0013] Step 1, presetting multiple fixed operating loads of the thermal power generating set according to the maximum output of the thermal power generating set and the maximum output of the water electrolysis hydrogen production system;

[0014] Step 2: Based on the control system, the AGC load instruction of the power grid, the load of the thermal power generating unit and the output of the water electrolysis hydrogen production system are obtained in real time, and the AGC load instruction of the power grid, the load of the thermal power generating unit and the output of the water electrolysis hydrogen production system are compared. Based on the comparison result, the operating load of the thermal power generating unit is adjusted, and the output of the water electrolysis hydrogen production system is determined.

[0015] Step 3: Based on the output of the water electrolysis hydrogen production system, the hydrogen produced by the water electrolysis hydrogen production system is mixed with natural gas and then sent to the gas turbine system for combustion.

[0016] Further, step 2 includes:

[0017] If the AGC load instruction is higher than the operating load of the thermal power generating unit, the operating load of the thermal power generating unit is increased to the nearest stable operating load that is higher than the AGC load instruction. The difference between the adjusted operating load and the AGC load instruction is the output of the water electrolysis hydrogen production system.

[0018] Furthermore, step 2 also includes:

[0019] If the AGC load instruction is lower than the operating load of the thermal power generating unit but higher than the stable operating load of the unit at a lower level, the operating load of the thermal power generating unit remains unchanged, and the difference between the unit operating load and the AGC load instruction is the output of the water electrolysis hydrogen production device.

[0020] Furthermore, step 2 also includes:

[0021] If the AGC load command is lower than the operating load of the thermal power generating unit and lower than the stable operating load of the unit at a lower level, the operating load of the thermal power generating unit will be reduced to the nearest stable operating load that is higher than the AGC load command. The difference between the adjusted operating load and the AGC load command is the output of the water electrolysis hydrogen production system.

[0022] Through the above scheme, by using the system and method of electrolytic hydrogen production and hydrogen mixed fuel for peak load regulation of thermal power plants, the gas turbine and the water electrolysis hydrogen production system are coordinated, and the hydrogen prepared by water electrolysis is mixed with natural gas and sent to the gas turbine for combustion. While improving the thermal efficiency of the gas turbine, the use of natural gas can be reduced, achieving the purpose of low carbon and environmental protection. It can be suitable for power plants with thermal power generating units and gas turbines, or industrial parks where thermal power generating units and gas turbines are configured in close proximity.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a structural block diagram of a system for peak load regulation of a thermal power plant using electrolytic hydrogen production and hydrogen mixed fuel. DETAILED DESCRIPTION

[0025] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0026] Ginseng Figure 1 As shown, this embodiment provides a system for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel, including a thermal power generation system 1, a water electrolysis hydrogen production system 2, a gas turbine system 3 and a control system 4;

[0027] The thermal power generation system 1 is connected to the water electrolysis hydrogen production system 2 through the plant power system, and is used to supply power to the water electrolysis hydrogen production system 2 through the plant power system to produce hydrogen;

[0028] The hydrogen produced by the water electrolysis hydrogen production system 2 is premixed with the natural gas of the gas turbine system 3 in a mixing chamber to form a hydrogen mixed fuel;

[0029] The control system 4 is connected to the thermal power generation system 1 and the water electrolysis hydrogen production system 2, and is used to obtain the AGC load instruction of the power grid in real time, and adjust the output of the water electrolysis hydrogen production system according to the operating load of the thermal power generation unit, so that the thermal power generation unit can maintain a long-term stable load operation. For example, when the sum of the AGC load instruction and the maximum output of the water electrolysis hydrogen production device is less than the current operating load of the thermal power unit, the control system 4 can send an instruction to the thermal power unit to reduce its load to the next specified load for stable operation.

[0030] Through the system of using electrolytic hydrogen production and hydrogen mixed fuel for peak load regulation of thermal power plants, the gas turbine and the water electrolysis hydrogen production system are matched, and the hydrogen produced by water electrolysis is mixed with natural gas and sent to the gas turbine for combustion. While improving the thermal efficiency of the gas turbine, the amount of natural gas can be reduced to achieve the purpose of low carbon and environmental protection. In this case, a larger output hydrogen electrolysis device can be adapted to meet the needs of gas turbine blending, and the thermal power unit can be operated at a stable load for a long time (such as a long-term stable full load, 75% load or 50% load). When the AGC instruction is between these loads, the excess electricity is used for electrolytic hydrogen production. The long-term stable load operation of the thermal power unit can reduce coal consumption and pollutant emissions, and at the same time can reduce the difficulty of operation of the operator and extend the life of the unit equipment.

[0031] In addition, the combined application of hydrogen energy storage and hydrogen-blended fuel gas turbines can realize on-site consumption of hydrogen, saving the cost of hydrogen storage and transportation. At the same time, it can enhance the sustainability of hydrogen energy storage and provide a guarantee for long-term stable load operation and deep peak regulation of thermal power units.

[0032] In this embodiment, the water electrolysis hydrogen production system 2 is one or a combination of alkaline water electrolysis hydrogen production equipment, proton exchange membrane electrolysis hydrogen production equipment, and solid oxide electrolysis hydrogen production equipment. The water electrolysis hydrogen production system preferably adopts alkaline water electrolysis hydrogen production mode, and the hydrogen production of a single hydrogen production module is 500Nm 3 (H 2 ) / h, a total of 16 modules. The energy consumption of hydrogen production is no more than 4.5kWh / Nm 3 (H 2 ), with a maximum output of 36MW.

[0033] In this embodiment, the output type of the water electrolysis hydrogen production system 2 is determined according to the output parameters of the gas turbine system 3 and the maximum hydrogen blending ratio allowed by the gas turbine.

[0034] In this embodiment, the blending ratio of hydrogen in the hydrogen mixed fuel is adjustable from 0 to 100%, and the blending ratio in actual operation is determined by the control system according to the AGC load instruction and the operating load of the thermal power unit.

[0035] In this embodiment, the gas turbine system 3 adopts an F-class gas turbine with an output of 300MW, and the load of the thermal power generating set is 300MW.

[0036] This embodiment also provides a method for applying the above system to perform peak load regulation in a thermal power plant, comprising the following steps:

[0037] Step 1, preset multiple fixed operating loads of the thermal power generating set according to the maximum output of the thermal power generating set and the maximum output of the water electrolysis hydrogen generating system 2. For example, if the maximum output of the thermal power generating set is a MW and the maximum output of the water electrolysis hydrogen generating device is b MW, the fixed operating load of the thermal power generating set can be designed as a, ab, a-2b…an*b ((an*b)MW is the minimum stable combustion load of the thermal power generating set).

[0038] Step 2, based on the control system 4, the grid AGC load instruction, the thermal power generator set load and the output of the water electrolysis hydrogen production system are obtained in real time, and the grid AGC load instruction, the thermal power generator set load and the output of the water electrolysis hydrogen production system are compared, and the thermal power generator set operating load is adjusted based on the comparison result, and the output of the water electrolysis hydrogen production system is determined.

[0039] Step 3: Based on the output of the water electrolysis hydrogen production system, the hydrogen produced by the water electrolysis hydrogen production system 2 is mixed with natural gas and then sent to the gas turbine for combustion.

[0040] In this embodiment, step 2 includes:

[0041] If the AGC load instruction is higher than the operating load of the thermal power generating unit, the operating load of the thermal power generating unit is increased to the nearest stable operating load that is higher than the AGC load instruction. The difference between the adjusted operating load and the AGC load instruction is the output of the water electrolysis hydrogen production system.

[0042] In this embodiment, step 2 also includes:

[0043] If the AGC load instruction is lower than the operating load of the thermal power generating unit but higher than the stable operating load of the unit at a lower level, the operating load of the thermal power generating unit remains unchanged, and the difference between the unit operating load and the AGC load instruction is the output of the water electrolysis hydrogen production device.

[0044] In this embodiment, step 2 also includes:

[0045] If the AGC load command is lower than the operating load of the thermal power generating unit and lower than the stable operating load of the unit at a lower level, the operating load of the thermal power generating unit will be reduced to the nearest stable operating load that is higher than the AGC load command. The difference between the adjusted operating load and the AGC load command is the output of the water electrolysis hydrogen production system.

[0046] In a specific embodiment, the process of using electrolysis to produce hydrogen and a hydrogen mixed fuel gas turbine to perform peak load regulation in a thermal power plant includes:

[0047] 1) According to the maximum output of the thermal power generating unit and the maximum output of the water electrolysis hydrogen production system, formulate several fixed operating loads of the thermal power generating unit. The maximum output of the thermal power generating unit is 300MW, and the maximum output of the water electrolysis hydrogen production device is 36MW. The fixed operating load of the thermal power generating unit can be designed as 300MW, 264MW, 228MW, 192MW and 156MW. Among them, 156MW is the minimum stable combustion load of the thermal power generating unit;

[0048] 2) The control system obtains the grid AGC load instructions, thermal power generator load and the output of the water electrolysis hydrogen production system in real time;

[0049] 3) The control system compares the grid AGC load instruction, the thermal power generator load and the output of the water electrolysis hydrogen production system;

[0050] 4) If the AGC load instruction is higher than the operating load of the thermal power generating unit, for example, if the AGC load instruction is 285MW and the operating load of the thermal power generating unit is 228MW, the load of the thermal power generating unit is increased to 300MW, and then the output of the water electrolysis hydrogen production system is adjusted to (300-285)MW, i.e. 15MW;

[0051] 5) If the AGC load instruction is lower than the operating load of the thermal power generating unit but higher than the stable operating load of the unit at a lower level, such as the AGC load instruction is 250MW and the operating load of the thermal power generating unit is 264MW, the load of the thermal power generating unit remains unchanged, and then the output of the water electrolysis hydrogen production system is adjusted to (264-250)MW, that is, 14MW;

[0052] 6) If the AGC load instruction is lower than the operating load of the thermal power generating unit and lower than the stable operating load of the unit at a lower level, such as the AGC load instruction is 200MW and the operating load of the thermal power generating unit is 264MW, the load of the thermal power generating unit is reduced to 228MW, and then the output of the water electrolysis hydrogen production system is adjusted to (228-200)MW, that is, 28MW;

[0053] 7) The hydrogen produced by the water electrolysis hydrogen production system is connected to the natural gas pipeline, mixed, and then sent to the gas turbine for combustion.

[0054] The present invention has the following technical effects:

[0055] 1. The present invention can ensure that the load of the thermal power generating set is always in stable operation, can reduce coal consumption and pollutant emissions, and can also reduce the operating difficulty of operators and extend the life of the unit equipment.

[0056] 2. The present invention can ensure that the thermal power generating set can timely and accurately track the AGC load instruction, and realize deep peak and frequency regulation of the thermal power generating set.

[0057] 3. The present invention can realize on-site consumption of hydrogen, saving the cost of hydrogen storage and transportation, and at the same time can enhance the sustainability of hydrogen energy storage.

[0058] 4. The present invention uses a mixture of hydrogen and natural gas to send to the gas turbine for combustion, which can reduce the amount of natural gas used while improving the thermal efficiency of the gas turbine, thereby achieving the goal of low carbon and environmental protection.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for peak shaving of a thermal power plant, which is applied to a system for peak shaving of a thermal power plant using electrolytic hydrogen production and hydrogen mixed fuel, Characterized in that, It includes the following steps: Step 1, according to the maximum output of the thermal power generating unit and the maximum output of the water electrolysis hydrogen production system, preset multiple fixed operating loads of the thermal power generating unit; Step 2, based on the control system, obtain the grid AGC load command, the load of the thermal power generating unit and the output of the water electrolysis hydrogen production system in real time, compare the grid AGC load command, the load of the thermal power generating unit and the output of the water electrolysis hydrogen production system, and adjust the operating load of the thermal power generating unit based on the comparison result, and determine the output of the water electrolysis hydrogen production system; Step 3, based on the output of the water electrolysis hydrogen production system, mix the hydrogen prepared by the water electrolysis hydrogen production system with natural gas and then send it to the gas turbine system for combustion; The said Step 2 includes: If the AGC load command is higher than the operating load of the thermal power generating unit, increase the operating load of the thermal power generating unit to the nearest stable operating load higher than the AGC load command, and the difference between the adjusted operating load and the AGC load command is the output of the water electrolysis hydrogen production system; The system for peak shaving of a thermal power plant using electrolytic hydrogen production and hydrogen mixed fuel includes a thermal power generation system, a water electrolysis hydrogen production system, a gas turbine system and a control system; The thermal power generation system is connected to the water electrolysis hydrogen production system through the plant power system, and is used to supply power to the water electrolysis hydrogen production system through the plant power system to produce hydrogen; The hydrogen prepared by the water electrolysis hydrogen production system is pre-mixed with the natural gas of the gas turbine system in the mixing chamber to form a hydrogen mixed fuel; The control system is connected to the thermal power generation system and the water electrolysis hydrogen production system, and is used to obtain the grid AGC load command in real time, and adjust the output of the water electrolysis hydrogen production system according to the operating load of the thermal power generating unit, so that the thermal power generating unit maintains a long-term stable load operation.

2. The method for peak shaving of a thermal power plant according to claim 1, Characterized in that, The water electrolysis hydrogen production system is one or a combination of an alkaline water electrolysis hydrogen production device, a proton exchange membrane electrolysis hydrogen production device, and a solid oxide electrolysis hydrogen production device.

3. The method for peak shaving of a thermal power plant according to claim 2, Characterized in that, The selection of the output of the water electrolysis hydrogen production system is determined according to the output parameters of the gas turbine system and the maximum hydrogen mixing ratio allowed by the gas turbine.

4. A system for peak shaving of a thermal power plant using electrolytic hydrogen production and hydrogen mixed fuel applying the method for peak shaving of a thermal power plant according to any one of claims 1-3, Characterized in that, It includes a thermal power generation system, a water electrolysis hydrogen production system, a gas turbine system and a control system; The thermal power generation system is connected to the water electrolysis hydrogen production system through the plant power system, and is used to supply power to the water electrolysis hydrogen production system through the plant power system to produce hydrogen; The hydrogen prepared by the water electrolysis hydrogen production system is pre-mixed with the natural gas of the gas turbine system in the mixing chamber to form a hydrogen mixed fuel; The control system is connected to the thermal power generation system and the water electrolysis hydrogen production system, and is used to obtain the AGC load instruction of the power grid in real time, and adjust the output of the water electrolysis hydrogen production system according to the operating load of the thermal power generation unit, so that the thermal power generation unit maintains long-term stable load operation.

5. The system for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel according to claim 4, It is characterized in that The water electrolysis hydrogen production system is one or a combination of alkaline water electrolysis hydrogen production equipment, proton exchange membrane electrolysis hydrogen production equipment, and solid oxide electrolysis hydrogen production equipment.

6. The system for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel according to claim 5, It is characterized in that The output selection of the water electrolysis hydrogen production system is determined according to the output parameters of the gas turbine system and the maximum hydrogen blending ratio allowed by the gas turbine.

7. The system for peak load regulation of thermal power plants using electrolytic hydrogen production and hydrogen mixed fuel according to claim 6, It is characterized in that The mixing ratio of hydrogen in the hydrogen mixed fuel is adjustable from 0 to 100%.

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